Measurement of behavior of secondary sealing areas of rotary engine apex seals - Two-piece nonsplit and three-piece slanted horizontal split types

Science.gov (United States)

Matsuura, Kenji; Terasaki, Kazuo; Yamane, Katsuki

1992-12-01

Behavior measurements have been made with two displacement sensors and an underseal pressure sensor, using an overhanging eccentric shaft-type single-rotor research engine equipped with a packaged multichannel slip ring. The two-piece seal was tilted to the leading and trailing sides of a seal slot during its travel along the rotor housing surface and vibrated on the top end of the leading side of the slot as a fulcrum after the shift from the trailing to the leading side of the slot after the minor axis on the spark plug side. As for the three-piece seal, its top part was also tilted in all operating conditions, although its bottom part made effective area contact with the side of the slot under light load conditions up to medium engine speeds. The working chamber pressure was induced in the underseal in the same manner as with the two-piece type.

Scleral fixation of a single-piece multifocal intraocular lens.

Science.gov (United States)

Can, Ertugrul; Basaran, M Resat; Gül, Adem

2013-01-01

We describe an ab interno technique for injector implantation of a one-piece multifocal intraocular lens (IOL). Transscleral fixation of multifocal posterior chamber IOL implantation using an injector with ab interno technique was performed in an eye of a 9-year-old girl who had undergone pars plana lensectomy 2 years before for bilateral lens subluxation with unknown etiology. No major complications were encountered during a 3-month follow-up of the patient and excellent centration was observed during the follow-up period. Her preoperative best spectacle-corrected distance visual acuity of 20/32 improved to uncorrected distance visual acuity of 20/25. Closed-loop design of IOL served the function of eyelets and position of the IOL was provided using only a 2-point fixation. Intraoperative position adjustment of the IOL provided an excellent centralization of multifocal IOL.

Pieces

DEFF Research Database (Denmark)

Jensen, Niels Henrik

1990-01-01

The report presents results from the SIP project (System Representation in Process Control). PIECES is a graphical, interactive user interface system designed and programmed as a tool for building, manipulating and using a Multilevel Flow Model (MFM - Morten Lind, Tecnical University of Denmark)....

Mechanical Performance Evaluation of a Top End Piece for Dual Cooled Fuels

International Nuclear Information System (INIS)

Kim, Jae Yong; Yoon, Kyung Ho; Kim, Hyung Kyu; Choi, Woo Seok

2011-01-01

A fuel assembly consists of five major components, i.e., a top end piece (TEP), a bottom end piece (BEP), spacer grids (SGs), guide tubes (GTs) and an instrumentation tube (IT): in addition, it also includes fuel rods (FRs). The TEP/BEP should satisfy stress intensity limits according to the conditions A and B of ASME, Section III, Division 1.Subsection NB. In a dual-cooled fuel assembly, the array and position of fuel rods are different from those in a conventional PWR fuel assembly; these changes are necessary for achieving power uprating. The flow plates of the TEP and BEP have to be modified accordingly. The pattern and shape of the flow holes were newly designed. To verify the strength compatibility, the Tresca stress limit according to the ASME code was investigated in the case of an axial load of 22.241 kN. In this paper, the stress linearization procedure for strength evaluation of a newly designed TEP is presented

Implant Gigi One-Piece Vs Two-Pieces Dalam Praktek Sehari-Hari

OpenAIRE

Kurnia, Dian Lestari; Ramadhani, Amilia; Hudyono, Rikko

2014-01-01

Saat ini, implant merupakan pilihan terbaik untuk menggantikan gigi yang tanggal, akan tetapi prosedur pemasangannya terbilang rumit dan memerlukan prosedur bedah kedua untuk pemasangan prostetik. Beberapa komplikasi seperti screw patah atau longgar dan adanya celah mikro pada batas pertemuan implant dan abutment dapat menyebabkan kegagalan implant. Studi kasus ini bertujuan untuk membahas mengenai keuntungan dan kerugian desain implant gigi one-piece dan two-pieces. Kasus pertama, seorang wa...

Product management of making large pieces through Rapid Prototyping PolyJet® technology

Science.gov (United States)

Belgiu, G.; Cărăuşu, C.; Şerban, D.; Turc, C. G.

2017-08-01

The rapid prototyping process has already become a classic manufacturing process for parts and assemblies, either polymeric or metal parts. Besides the well-known advantages and disadvantages of the process, the use of 3D printers has a great inconvenience: the overall dimensions of the parts are limited. Obviously, there is a possibility to purchase a larger (and more expensive) 3D printer, but there are always larger pieces to be manufactured. One solution to this problem is the splitting of parts into several components that can be manufactured. The component parts can then be assembled in a single piece by known methods such as welding, gluing, screwing, etc. This paper shows our experience in making large pieces on the Strarasys® Objet24 printer, pieces larger than the tray sizes. The results obtained are valid for any 3D printer using the PolyJet® process.

Implant Gigi One-Piece vs Two-Pieces dalam Praktek Sehari-Hari

OpenAIRE

Kurnia, Dian Lestari; Ramadhani, Amilia; Hudyono, Rikko

2014-01-01

Saat ini, implant merupakan pilihan terbaik untuk menggantikan gigi yang tanggal, akan tetapi prosedur pemasangannya terbilang rumit dan memerlukan prosedur bedah kedua untuk pemasangan prostetik. Beberapa komplikasi seperti screw patah atau longgar dan adanya celah mikro pada batas pertemuan implant dan abutment dapat menyebabkan kegagalan implant. Studi kasus ini bertujuan untuk membahas mengenai keuntungan dan kerugian desain implant gigi one-piece dan two-pieces. Kasus pertama, seorang wa...

Single-Crystal Mesoporous ZnO Thin Films Composed of Nanowalls

KAUST Repository

Wang, Xudong; Ding, Yong; Li, Zhou; Song, Jinhui; Wang, Zhong Lin

2009-01-01

This paper presents a controlled, large scale fabrication of mesoporous ZnO thin films. The entire ZnO mesoporous film is one piece of a single crystal, while high porosity made of nanowalls is present. The growth mechanism was proposed

Multiple piece turbine rotor blade

Science.gov (United States)

Jones, Russell B; Fedock, John A

2013-05-21

A multiple piece turbine rotor blade with a shell having an airfoil shape and secured between a spar and a platform with the spar including a tip end piece. a snap ring fits around the spar and abuts against the spar tip end piece on a top side and abuts against a shell on the bottom side so that the centrifugal loads from the shell is passed through the snap ring and into the spar and not through a tip cap dovetail slot and projection structure.

On some perculiarities of microstructure formation and the mechanical properties in thick-walled pieces of cast iron and their application as reactor structural materials

International Nuclear Information System (INIS)

Janakiev, N.

1975-01-01

The following problems are dealt with in the present work: Microstructure formation and mechanical properties of thick-walled cast pieces, influence of neutron irradiation on the mechanical properties, manufacture of thick-walled castings for reactor construction, application of cast iron as reactor structural material. It is shown that graphite formation plays an extremely important role regarding the mechanical properties. A new construction for vertically stressed pressure vessels is given. These vessels can be fabricated mainly of cast iron with graphite spheres, cast steel, or a combination of both depending on the operational pressure. (GSCH) [de

Prediction of hardness in pieces of quenched and tempered steel

International Nuclear Information System (INIS)

Yanzon, Rodolfo Carlos; Rodriguez, Augusto; Sanchez, Arlington Ricardo

2006-01-01

diameter. The result from the computer process should be the 'U curve of hardnesses', based on the prediction of the hardness value that the material will have, at points along the radius of a circular piece. So the engineer now has an easy, quick design tool with acceptable margins of error. When selecting the steel to use in producing the mechanical piece, he/she can make a better comparison of the possible offers of treated material, with respect to the data provided by the calculation of requests (CW)

Modeling The Interaction Effects Between Tools And The Work Piece For Metal Forming Processes

International Nuclear Information System (INIS)

Franzke, Martin; Puchhala, Sreedhar; Dackweiler, Harald

2007-01-01

In metal forming processes especially in cold forming, elastic deformation of the tools has a big impact on the final shape of the work-piece. Computation of such processes considering the plastic effects of the work-piece and elastic deformations of the tools at a time in a single FE model complicates to manage the convergence criteria. This situation is even aggravated if the contact situations (between working and support rolls) have to be considered in the simulation, which requires a very fine discretization of the contact zones of both the tool and work piece. This paper presents recently developed concept which meets the above mentioned demands very effectively. Within this concept, the computation of the elastic effects of the tools is separated from the process simulation (which considers elastic-plastic effects of the work-piece). Both simulations are coupled via automatic data interchange, which is bi-directional, because both simulations influence each other. The advantages of this concept include a quite easy to handle contact situations in process simulation, smaller stiffness matrix compared to single model approach and good convergence of the computation. This concept is highly generalized and successfully applied to simulate rolling, drawing, extrusion and forging processes. The above mentioned concept is being implemented into the FE package PEP and LARSTRAN/SHAPE. Rolling experiments are conducted in duo and quarto configuration. Optical three-dimensional digitalizing system was used to measure the deformations within the machine and work-piece profile. These results are used for the validation of FE simulations. This work is being sponsored by the German Research Foundation (DFG) through the project ''Interaction effects between processes and structures-SPP1180''

Device for inspecting pieces of luggage by means of X-rays

International Nuclear Information System (INIS)

Kunze, C.; Dennhoven, M.

1977-01-01

Luggage inspection facility using X-rays, the piece of luggage appearing as a shadow image on a luminous screen. The shielded casing contains a control compartment holding the piece of luggage. During radioscopy the control compartment is closed by means of a shielding tunnel. As during mechanism for the shielding tunnel there is used a so-called linear motor with a moving magnetic field, operating a bar connected with the shielding tunnel through a flexible coupling. The motor is turned off in its terminal positions by means of a magnet and protective gas contacts. (HP) 891 HP [de

Push piece for spent fuel elements magazine

International Nuclear Information System (INIS)

Griveau, R.; Kerlau, D.; Tucoulat, D.; Colas, J.; Pellier, R.

1989-01-01

The push piece permits the displacement of little section elements in a magazine of high section. At the end of cut, the push piece leans its flank against an auxiliary blank holder and the element is pushed by a paddle, the push piece being immobilized [fr

Devoluming and stabilizing method for end piece

International Nuclear Information System (INIS)

Ikeda, Satoshi; Shiotsuki, Msao; Kawamura, Shigeyoshi; Komatsu, Fumiaki.

1991-01-01

As a first method, end pieces and other radioactive metal wastes are filled as a mixture in a vessel, and preliminary compression is conducted. Then, the bulk density of the radioactive metal wastes is reduced and gaps in the end pieces are filled with radioactive metal wastes. If they are applied with heat treatment under high pressure in this state together with the vessel, they are devolumed and stabilized without damaging the vessel. As a second method, metal powders are mixed and filled in the vessel together with the end pieces. The gaps in the end pieces are filled with the metal powders and if they are applied with heat treatment under high pressure in this state together with the vessel, the end pieces are devolumed and stabilized without damaging the vessel in the same manner. This can devolume and stabilize the end pieces separated from nuclear fuel assemblies easily and safely. (T.M.)

Solving intraocular lens-related pigment dispersion syndrome with repositioning of primary sulcus implanted single-piece IOL in the capsular bag.

Science.gov (United States)

Kohnen, Thomas; Kook, Daniel

2009-08-01

We describe 2 cases of pigment dispersion syndrome (PDS) after uneventful phacoemulsification and implantation of a posterior chamber single-piece intraocular lens (IOL) with a sharp-edge design. In both cases, several days after IOL implantation, marked pigment dispersion was seen on the iris and in the trabecular meshwork, associated with an elevation in intraocular pressure (IOP). Thorough examination showed that the implanted IOL was in the ciliary sulcus. After surgical repositioning of both IOLs in the capsular bag, the pigment dispersion regressed and the IOP returned to normal limits. The 2 cases suggest that particularly in PDS patients, an IOL with an anterior sharp-edge design should be implanted in the capsular bag. Implantation in the ciliary sulcus should be avoided.

Magnetic field shimming of a permanent magnet using a combination of pieces of permanent magnets and a single-channel shim coil for skeletal age assessment of children.

Science.gov (United States)

Terada, Y; Kono, S; Ishizawa, K; Inamura, S; Uchiumi, T; Tamada, D; Kose, K

2013-05-01

We adopted a combination of pieces of permanent magnets and a single-channel (SC) shim coil to shim the magnetic field in a magnetic resonance imaging system dedicated for skeletal age assessment of children. The target magnet was a 0.3-T open and compact permanent magnet tailored to the hand imaging of young children. The homogeneity of the magnetic field was first improved by shimming using pieces of permanent magnets. The residual local inhomogeneity was then compensated for by shimming using the SC shim coil. The effectiveness of the shimming was measured by imaging the left hands of human subjects and evaluating the image quality. The magnetic resonance images for the child subject clearly visualized anatomical structures of all bones necessary for skeletal age assessment, demonstrating the usefulness of combined shimming. Copyright © 2013 Elsevier Inc. All rights reserved.

Musings on the puzzle piece.

Science.gov (United States)

Goin-Kochel, Robin P

2016-02-01

Following is a brief musing on Roy Grinker's discussion of what the puzzle piece symbolizes for autism during his presentation at the 2015 International Meeting for Autism Research. In his words, "The puzzle piece is ubiquitous." It likely holds a different meaning for each of us, and this is how one autism researcher sees it. © The Author(s) 2015.

Torque Removal Evaluation of Screw in One-Piece and Two-Piece Abutments Tightened with a Handheld screwdriver

Directory of Open Access Journals (Sweden)

Jalil Ghanbarzadeh

2013-12-01

Full Text Available Introduction: Some clinicians use a handheld screw driver instead of a torque wrench to definitively tighten abutment screws. The aim of this study was to compare the removal torque of one-piece and two-piece abutments tightened with a handheld driver and a torque control ratchet. Methods: 40 ITI implants were placed in acrylic blocks and divided into 4 groups. In groups one and two, 10 ITI one-piece abutments (Solid® and in groups three and four, 10 ITI two-piece abutments (Synocta® were placed on the implants. In groups one and three abutments were tightened by 5 experienced males and 5 experienced females using a handheld driver. In groups two and four abutments were tightened using a torque wrench with torque values of 10, 20 and 35 N.cm. Insertion torque and removal torque values of the abutments were measured with a digital torque meter. Results: The insertion torque values (ITVs of males in both abutments were significantly higher than those of females. ITVs in both Solid® and Synocta® abutments tightened with a handheld screwdriver were similar to the torque of 20 N.cm in the torque wrench. Removal torque values (RTVs of solid® abutments were higher than those of synocta® abutments. Conclusion: The one- piece abutments (solid® showed higher RTVs than the two-piece abutments (synocta®. Hand driver does not produce sufficient preload force for the final tightening of the abutment

Accuracy of Setting Work-pieces on Automatic Lines with Pallet-fixtures

Directory of Open Access Journals (Sweden)

L. A. Kolesnikov

2015-01-01

Full Text Available The accuracy of positioning surfaces to be processed on automatic lines with pallet-fixtures essentially depends on the setting error of the pallet-fixtures with work-pieces in ready-to-work position.The applied methods for calculating the setting error do not give a complete picture of the possible coordinates of the point when in the pallet is displaced in different directions.The aim of the work was to determine an accuracy of the setting work-pieces on automatic lines with pallets-fixtures, using a computational and analytical method, to improve a manufacturing precision of parts.The currently used methods to calculate the setting error do not give a complete picture of the possible coordinates of the point of the pallet displacement in different directions. The paper offers a method of equivalent mechanism to determine all the variety of options for displacements in the horizontal plane with a diverse combination of angular and plane-parallel displacements.Using a four-bar linkage, as an equivalent mechanism, allows us to define a zone of the possible positions of any point of the work-piece pallet platform, as the zone bounded by the coupler curve. In case the gaps in the nodes of the two fixtures are equal the zone of possible positions of the point in the parallel displacement of the platform is determined by the circumference and at an angular displacement by the ellipse.The obtained analytical dependences allow us to determine the error at the stage of design with the certain gaps in the fixture nodes.The above method of calculation makes it possible to define a zone of the appropriate placement of the work-piece on its platform for the specified parameters of the pallet to meet conditions for ensuring the coordinate accuracy of the processed axes of holes.

Single banking supervision and the single supervisory mechanism

Directory of Open Access Journals (Sweden)

Gheorghe, C. A.

2013-06-01

Full Text Available A resolution seems to have been found for the banking crisis. The first steps have been made towards the construction of the Economic and Monetary Union, steps involving the single supervision of banks, in order to avoid the discount of a new financial crisis on the expense of the EU state members. The Single Supervisory Mechanism – SSM is to become effective as of March 1, 2014, at the earliest.

Bite Reconstruction in the Aesthetic Zone Using One-Piece Bicortical Screw Implants

Directory of Open Access Journals (Sweden)

Stefan Ihde

2018-01-01

Full Text Available The aim of this article was to present the clinical application of a new, smooth surfaced one-piece bicortical screw implant with immediate loading protocol. An 18-year-old, healthy male patient with a history of total dislocation and replantation of teeth 11 and 21 in early childhood was admitted to the clinic. Teeth 11 and 21 were extracted, and two long one-piece implants were inserted at extraction sockets in one surgical session under local anesthesia. Temporary composite crowns were placed in the patient on the same day. After 3 months, the single-phase two-layer impression was made and the composite crowns were replaced with metal-ceramic crowns. After 12 months, satisfactory aesthetic and functional results were obtained.

Surface dimpling on rotating work piece using rotation cutting tool

Science.gov (United States)

Bhapkar, Rohit Arun; Larsen, Eric Richard

2015-03-31

A combined method of machining and applying a surface texture to a work piece and a tool assembly that is capable of machining and applying a surface texture to a work piece are disclosed. The disclosed method includes machining portions of an outer or inner surface of a work piece. The method also includes rotating the work piece in front of a rotating cutting tool and engaging the outer surface of the work piece with the rotating cutting tool to cut dimples in the outer surface of the work piece. The disclosed tool assembly includes a rotating cutting tool coupled to an end of a rotational machining device, such as a lathe. The same tool assembly can be used to both machine the work piece and apply a surface texture to the work piece without unloading the work piece from the tool assembly.

Influence of temperature and composition in the mechanical resistance and porosity of ceramic pieces

Directory of Open Access Journals (Sweden)

Jordán Vidal, M. M.

2001-03-01

Full Text Available We have tried to establish a relationship between the raw material and the mechanical properties of ceramic pieces subjected to different firing processes, so under the determinant of the thermal process we have done a follow up on the petrogenetic process that the manufacture of ceramics represents. This is evaluated in terms of the mechanical behaviour of the ceramic tile bodies, which have been normalised and submitted to tests for flexion. The principal objective is to be able to indicate what the optimum firing temperature for each sample is, and to determine what it is in the ceramic body which offers the greatest resistance when a specific force is applied. The study of the texture of the ceramic body will be considered mainly in relation to the existent porosity, as well as its distribution, which conditions its characteristics and specifications. The relation between porosity and the parameters that describe the porous texture of the ceramic tile pieces studied is complicated because of the fact that these have many pores with a complex and irregular spatial disposition, with a broad distribution of forms and sizes, and as such they do not fit into established empirical equations.

Se ha tratado de establecer la relación entre materia prima y propiedades mecánicas de piezas cerámicas sometidas a procesos de cocción diversos. Bajo el condicionante del proceso térmico se realiza un seguimiento del proceso petrogenético que representa la fabricación cerámica y se evalúa a través del comportamiento mecánico de probetas cerámicas normalizadas y sometidas a ensayos de flexión. El objetivo principal es poder indicar cuál es la temperatura óptima de cocción para cada muestra y determinar cuál es aquélla en que la probeta cerámica ofrece una mayor resistencia al aplicarle una determinada carga. El estudio de la textura de la matriz cerámica es de gran interés en relación con la porosidad, asi como su distribuci

Fractal dimension analysis of complexity in Ligeti piano pieces

Science.gov (United States)

Bader, Rolf

2005-04-01

Fractal correlation dimensional analysis has been performed with whole solo piano pieces by Gyrgy Ligeti at every 50ms interval of the pieces. The resulting curves of development of complexity represented by the fractal dimension showed up a very reasonable correlation with the perceptional density of events during these pieces. The seventh piece of Ligeti's ``Musica ricercata'' was used as a test case. Here, each new part of the piece was followed by an increase of the fractal dimension because of the increase of information at the part changes. The second piece ``Galamb borong,'' number seven of the piano Etudes was used, because Ligeti wrote these Etudes after studying fractal geometry. Although the piece is not fractal in the strict mathematical sense, the overall structure of the psychoacoustic event-density as well as the detailed event development is represented by the fractal dimension plot.

Continuum mechanics of single-substance bodies

CERN Document Server

Eringen, A Cemal

1975-01-01

Continuum Physics, Volume II: Continuum Mechanics of Single-Substance Bodies discusses the continuum mechanics of bodies constituted by a single substance, providing a thorough and precise presentation of exact theories that have evolved during the past years. This book consists of three parts-basic principles, constitutive equations for simple materials, and methods of solution. Part I of this publication is devoted to a discussion of basic principles irrespective of material geometry and constitution that are valid for all kinds of substances, including composites. The geometrical notions, k

Development of debris resistant bottom end piece

International Nuclear Information System (INIS)

Lee, Jae Kyung; Sohn, Dong Seong; Yim, Jeong Sik; Hwang, Dae Hyun; Song, Kee Nam; Oh, Dong Seok; Rhu, Ho Sik; Lee, Chang Woo; Kim, Seong Soo; Oh, Jong Myung

1993-12-01

Debris-related fuel failures have been identified as one of the major causes of fuel failures. In order to reduce the possibility of debris-related fuel failures, it is necessary to develop Debris-Resistant Bottom End Piece. For this development, mechanical strength test and pressure drop test were performed, and the test results were analyzed. And the laser cutting, laser welding and electron beam welding technology, which were the core manufacturing technology of DRBEP, were developed. Final design were performed, and the final drawing and specifications were prepared. The prototype of DRBEP was manufactured according to the developed munufacturing procedure. (Author)

Underwater transporting method and device for incore structure cutting piece

International Nuclear Information System (INIS)

Kurosawa, Koichi; Chiba, Noboru; Chiba, Isao; Takada, Hiroshi; Furukawa, Hideyasu; Chiba, Noboru.

1996-01-01

Cutting pieces are handled by using a pick-up device connected with a wire ropes, a take-up drum, chains and a winch as cutting piece handling means, and moved freely on the water surface by a propulsion machine of a transporting means of the device to transfer them under water to a predetermined position. The pick-up device is lifted by taking-up the rope by the rotation of the take-up drum using chain-driving by way of the winch and the chains. The cut pieces are stored in a cask by lowering them in the cask and releasing the handling. In addition, if the weight of the cut pieces is recognized before cutting, and the load of the weight of the cut pieces is applied to the device previously, the balance of the device and the cut pieces can be kept, and cut pieces can be transported under water always stably. Further, if the cut pieces are supported upon cutting operation, the cut pieces are made stable, and cutting operation with good efficiency can be attained. (N.H.)

Alveolar Bone Resorption Evaluation Around Single-piece Designed Bicortical Implants, Using Immediate Loading Protocol, Based on Orthopantomographs

Directory of Open Access Journals (Sweden)

Száva Dániel-Tamás

2017-12-01

Full Text Available Background: Inserting dental implants in severely atrophied jawbones is a great challenge for the dental practitioner. There are an increasing number of patients who choose dental implantanchored prosthetic restorations despite compromised bone quality and quantity. There have been numerous attempts in adapting implant design for the atrophic crestal bone. One-piece, needle-type basal implant design is a typical design for these cases. These implants are inserted in the remaining compact bone located in the basal aspect of the jawbones. If high primary stability is achieved, these implants are used for immediate loading protocol. From many points of view, this technique is based on contradictory principles compared to classic implant surgery and loading protocols. The aim of this study was to investigate the long-term success of basal one-piece short-diameter dental implants used for immediate loading protocol.

Mechanism of the superior mechanical strength of nanometer-sized metal single crystals revealed

KAUST Repository

Afify, N. D.

2013-10-01

Clear understanding of the superior mechanical strength of nanometer-sized metal single crystals is required to derive advanced mechanical components retaining such superiority. Although high quality studies have been reported on nano-crystalline metals, the superiority of small single crystals has neither been fundamentally explained nor quantified to this date. Here we present a molecular dynamics study of aluminum single crystals in the size range from 4.1 nm to 40.5 nm. We show that the ultimate mechanical strength deteriorates exponentially as the single crystal size increases. The small crystals superiority is explained by their ability to continuously form vacancies and to recover them. © 2013 Published by Elsevier B.V.

Last piece of ATLAS takes the plunge

CERN Multimedia

2008-01-01

On Friday 29 February the second small wheel was lowered 100 metres underground into the ATLAS cavern in front of a captivated audience. Although called the "small wheels" they are small in name only - each wheel is 9.3 metres in diameter and weighs 100 tonnes including the massive shielding elements. This piece completes ATLAS’ muon spectrometer, which has the ability to accurately track particles to the width of a human hair. The first piece of ATLAS was installed in 2003 and, five years later, this small wheel is the final large piece of the detector to take the subterranean voyage to its final resting place.

Estimation of mechanical properties of single wall carbon nanotubes ...

Indian Academy of Sciences (India)

Molecular mechanics; single wall carbon nanotube; mechanical proper- ... Fracture Mechanics); Rossi & Meo 2009). Furthermore, the work carried out by Natsuki & Endo. (2004), Xiao et al (2005) and Sun & Zhao (2005) in the direction of ..... Jin Y and Yuan F G 2003 Simulation of elastic properties of single walled carbon ...

Mechanical transduction via a single soft polymer

Science.gov (United States)

Hou, Ruizheng; Wang, Nan; Bao, Weizhu; Wang, Zhisong

2018-04-01

Molecular machines from biology and nanotechnology often depend on soft structures to perform mechanical functions, but the underlying mechanisms and advantages or disadvantages over rigid structures are not fully understood. We report here a rigorous study of mechanical transduction along a single soft polymer based on exact solutions to the realistic three-dimensional wormlike-chain model and augmented with analytical relations derived from simpler polymer models. The results reveal surprisingly that a soft polymer with vanishingly small persistence length below a single chemical bond still transduces biased displacement and mechanical work up to practically significant amounts. This "soft" approach possesses unique advantages over the conventional wisdom of rigidity-based transduction, and potentially leads to a unified mechanism for effective allosterylike transduction and relay of mechanical actions, information, control, and molecules from one position to another in molecular devices and motors. This study also identifies an entropy limit unique to the soft transduction, and thereby suggests a possibility of detecting higher efficiency for kinesin motor and mutants in future experiments.

Time to Stop Holding the Elevator: A New Piece of the Transport Protein Mechanism Puzzle.

Science.gov (United States)

Vastermark, Ake; Saier, Milton H

2016-06-07

In this issue of Structure, McCoy et al. (2016) describe the 2.55-Å X-ray structure of the outward-facing occluded conformation of the Bacillus cereus maltose transporter MalT. This structure represents the penultimate piece needed to complete the picture of the transport cycle of the glucose superfamily of membrane-spanning EIIC components. Copyright © 2016 Elsevier Ltd. All rights reserved.

75 FR 28051 - Public Workshop: Pieces of Privacy

Science.gov (United States)

2010-05-19

... DEPARTMENT OF HOMELAND SECURITY Office of the Secretary Public Workshop: Pieces of Privacy AGENCY: Privacy Office, DHS. ACTION: Notice announcing public workshop. SUMMARY: The Department of Homeland Security Privacy Office will host a public workshop, ``Pieces of Privacy.'' DATES: The workshop will be...

Single-hit mechanism of tumour cell killing by radiation.

Science.gov (United States)

Chapman, J D

2003-02-01

To review the relative importance of the single-hit mechanism of radiation killing for tumour response to 1.8-2.0 Gy day(-1) fractions and to low dose-rate brachytherapy. Tumour cell killing by ionizing radiation is well described by the linear-quadratic equation that contains two independent components distinguished by dose kinetics. Analyses of tumour cell survival curves that contain six or more dose points usually provide good estimates of the alpha- and beta-inactivation coefficients. Superior estimates of tumour cell intrinsic radiosensitivity are obtained when synchronized populations are employed. The characteristics of single-hit inactivation of tumour cells are reviewed and compared with the characteristics of beta-inactivation. Potential molecular targets associated with single-hit inactivation are discussed along with strategies for potentiating cell killing by this mechanism. The single-hit mechanism of tumour cell killing shows no dependence on dose-rate and, consequently, no evidence of sublethal damage repair. It is uniquely potentiated by high linear-energy-transfer radiation, exhibits a smaller oxygen enhancement ratio and exhibits a larger indirect effect by hydroxyl radicals than the beta-mechanism. alpha-inactivation coefficients vary slightly throughout interphase but mitotic cells exhibit extremely high alpha-coefficients in the range of those observed for lymphocytes and some repair-deficient cells. Evidence is accumulating to suggest that chromatin in compacted form could be a radiation-hypersensitive target associated with single-hit radiation killing. Analyses of tumour cell survival curves demonstrate that it is the single-hit mechanism (alpha) that determines the majority of cell killing after doses of 2Gy and that this mechanism is highly variable between tumour cell lines. The characteristics of single-hit inactivation are qualitatively and quantitatively distinct from those of beta-inactivation. Compacted chromatin in tumour cells

FEA and microstructure characterization of a one-piece Y-TZP abutment.

Science.gov (United States)

da Silva, Lucas Hian; Ribeiro, Sebastião; Borges, Alexandre Luís Souto; Cesar, Paulo Francisco; Tango, Rubens Nisie

2014-11-01

The most important drawback of dental implant/abutment assemblies is the need for a fixing screw. This study aimed to develop an esthetic one-piece Y-TZP abutment to suppress the use of the screw. Material characterization was performed using a bar-shaped specimen obtained by slip-casting to validate the method prior to prototype abutment fabrication by the same process. The mechanical behavior of the prototype abutment was verified and compared with a conventional abutment by finite element analysis (FEA). The abutment was evaluated by micro-CT analysis and its density was measured. FEA showed stress concentration at the first thread pitch during installation and in the cervical region during oblique loading for both abutments. However, stress concentration was observed at the base of the screw head and stem in the conventional abutment. The relative density for the fabricated abutment was 95.68%. Micro-CT analysis revealed the presence of elongated cracks with sharp edges over the surface and porosity in the central region. In the light of these findings, the behavior of a one-piece abutment is expected to be better than that of the conventional model. New studies should be conducted to clarify the performance and longevity of this one-piece Y-TZP abutment. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

7 CFR 51.1435 - U.S. Commercial Pieces.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false U.S. Commercial Pieces. 51.1435 Section 51.1435 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... STANDARDS) United States Standards for Grades of Shelled Pecans Grades § 51.1435 U.S. Commercial Pieces. The...

Eight piece quadrupole magnet, method for aligning quadrupole magent pole tips

Science.gov (United States)

Jaski, Mark S.; Liu, Jie; Donnelly, Aric T.; Downey, Joshua S.; Nudell, Jeremy J.; Jain, Animesh

2018-01-30

The invention provides an alternative to the standard 2-piece or 4-piece quadrupole. For example, an 8-piece and a 10-piece quadrupole are provided whereby the tips of each pole may be adjustable. Also provided is a method for producing a quadrupole using standard machining techniques but which results in a final tolerance accuracy of the resulting construct which is better than that obtained using standard machining techniques.

[Study on quality standards of decoction pieces of salt Alpinia].

Science.gov (United States)

Li, Wenbing; Hu, Changjiang; Long, Lanyan; Huang, Qinwan; Xie, Xiuqiong

2010-12-01

To establish the quality criteria for decoction pieces of salt Alpinia. Decoction pieces of salt Alpinia were measured with moisture, total ash, acid-insoluble ash, water-extract and volatile oils according to the procedures recorded in the Chinese Pharmacopoeia 2010. The content of Nootkatone was determined by HPLC, and NaCl, by chloridion electrode method. We obtained results of total ash, acid-insoluble ash, water-extract and volatile oils of 10 batches of decoction pieces of salt Alpinia moisture; Meanwhile we set the HPLC and chloridion electrode method. This research established a fine quality standard for decoction pieces of salt Alpinia.

Mechanism of the superior mechanical strength of nanometer-sized metal single crystals revealed

KAUST Repository

Afify, N. D.; Salem, H. G.; Yavari, A.; El Sayed, Tamer S.

2013-01-01

Clear understanding of the superior mechanical strength of nanometer-sized metal single crystals is required to derive advanced mechanical components retaining such superiority. Although high quality studies have been reported on nano

The mechanism distinguishability problem in biochemical kinetics: the single-enzyme, single-substrate reaction as a case study.

Science.gov (United States)

Schnell, Santiago; Chappell, Michael J; Evans, Neil D; Roussel, Marc R

2006-01-01

A theoretical analysis of the distinguishability problem of two rival models of the single enzyme-single substrate reaction, the Michaelis-Menten and Henri mechanisms, is presented. We also outline a general approach for analysing the structural indistinguishability between two mechanisms. The approach involves constructing, if possible, a smooth mapping between the two candidate models. Evans et al. [N.D. Evans, M.J. Chappell, M.J. Chapman, K.R. Godfrey, Structural indistinguishability between uncontrolled (autonomous) nonlinear analytic systems, Automatica 40 (2004) 1947-1953] have shown that if, in addition, either of the mechanisms satisfies a particular criterion then such a transformation always exists when the models are indistinguishable from their experimentally observable outputs. The approach is applied to the single enzyme-single substrate reaction mechanism. In principle, mechanisms can be distinguished using this analysis, but we show that our ability to distinguish mechanistic models depends both on the precise measurements made, and on our knowledge of the system prior to performing the kinetics experiments.

Last piece of the puzzle for ATLAS

CERN Multimedia

Clare Ryan

At around 15.40 on Friday 29th February the ATLAS collaboration cracked open the champagne as the second of the small wheels was lowered into the cavern. Each of ATLAS' small wheels are 9.3 metres in diameter and weigh 100 tonnes including the massive shielding elements. They are the final parts of ATLAS' muon spectrometer. The first piece of ATLAS was installed in 2003 and since then many detector elements have journeyed down the 100 metre shaft into the ATLAS underground cavern. This last piece completes this gigantic puzzle.

Individuality in harpsichord performance: disentangling performer- and piece-specific influences on interpretive choices.

Science.gov (United States)

Gingras, Bruno; Asselin, Pierre-Yves; McAdams, Stephen

2013-01-01

Although a growing body of research has examined issues related to individuality in music performance, few studies have attempted to quantify markers of individuality that transcend pieces and musical styles. This study aims to identify such meta-markers by discriminating between influences linked to specific pieces or interpretive goals and performer-specific playing styles, using two complementary statistical approaches: linear mixed models (LMMs) to estimate fixed (piece and interpretation) and random (performer) effects, and similarity analyses to compare expressive profiles on a note-by-note basis across pieces and expressive parameters. Twelve professional harpsichordists recorded three pieces representative of the Baroque harpsichord repertoire, including three interpretations of one of these pieces, each emphasizing a different melodic line, on an instrument equipped with a MIDI console. Four expressive parameters were analyzed: articulation, note onset asynchrony, timing, and velocity. LMMs showed that piece-specific influences were much larger for articulation than for other parameters, for which performer-specific effects were predominant, and that piece-specific influences were generally larger than effects associated with interpretive goals. Some performers consistently deviated from the mean values for articulation and velocity across pieces and interpretations, suggesting that global measures of expressivity may in some cases constitute valid markers of artistic individuality. Similarity analyses detected significant associations among the magnitudes of the correlations between the expressive profiles of different performers. These associations were found both when comparing across parameters and within the same piece or interpretation, or on the same parameter and across pieces or interpretations. These findings suggest the existence of expressive meta-strategies that can manifest themselves across pieces, interpretive goals, or expressive devices.

Individuality in harpsichord performance: Disentangling performer- and piece-specific influences on interpretive choices

Directory of Open Access Journals (Sweden)

Bruno eGingras

2013-11-01

Full Text Available Although a growing body of research has examined issues related to individuality in music performance, few studies have attempted to quantify markers of individuality that transcend pieces and musical styles. This study aims to identify such meta-markers by discriminating between influences linked to specific pieces or interpretive goals and performer-specific playing styles, using two complementary statistical approaches: linear mixed models (LMMs to estimate fixed (piece and interpretation and random (performer effects, and similarity analyses to compare expressive profiles on a note-by-note basis across pieces and expressive parameters. Twelve professional harpsichordists recorded three pieces representative of the Baroque harpsichord repertoire, including three interpretations of one of these pieces, each emphasizing a different melodic line, on an instrument equipped with a MIDI console. Four expressive parameters were analyzed: articulation, note onset asynchrony, timing, and velocity. LMMs showed that piece-specific influences were much larger for articulation than for other parameters, for which performer-specific effects were predominant, and that piece-specific influences were generally larger than effects associated with interpretive goals. Some performers consistently deviated from the mean values for articulation and velocity across pieces and interpretations, suggesting that global measures of expressivity may in some cases constitute valid markers of artistic individuality. Similarity analyses detected significant associations among the magnitudes of the correlations between the expressive profiles of different performers. These associations were found both when comparing across parameters and within the same piece or interpretation, or on the same parameter and across pieces or interpretations. These findings suggest the existence of expressive meta-strategies that can manifest themselves across pieces, interpretive goals, or

Image analysis of multiple moving wood pieces in real time

Science.gov (United States)

Wang, Weixing

2006-02-01

This paper presents algorithms for image processing and image analysis of wood piece materials. The algorithms were designed for auto-detection of wood piece materials on a moving conveyor belt or a truck. When wood objects on moving, the hard task is to trace the contours of the objects in n optimal way. To make the algorithms work efficiently in the plant, a flexible online system was designed and developed, which mainly consists of image acquisition, image processing, object delineation and analysis. A number of newly-developed algorithms can delineate wood objects with high accuracy and high speed, and in the wood piece analysis part, each wood piece can be characterized by a number of visual parameters which can also be used for constructing experimental models directly in the system.

Mine cross piece

Energy Technology Data Exchange (ETDEWEB)

Belik, I P; Gorbatenko, A Ye

1982-01-01

The mine cross piece includes main and supplementary parachute-formed cupolas made of air-impermeable fabric, resources for attachment made in the form of shroud lines. In order to improve its reliability with prolonged localization of an underground fire, the cavity between the cupolas connects to the source of fast-hardening material. In this case the cupolas are arranged co-directionally in relation to each other, while the shroud lines of the main are attached to the cupola of the supplemental which is made with perforations.

Process for the fixing of a metallic end piece on a tubular component

International Nuclear Information System (INIS)

Charpin, Jean.

1975-01-01

Under this invention the process makes it possible to joint a tubular component and in particular a tubular filter and an end piece, with a connection of great mechanical strength, perfectly leak proof and with excellent corrosion resistance, particularly with respect to fluorinated by-products. This process is therefore of great worth in fixing to a bearer a thin ceramic compound tubular filter element, since such a filter can be used in particular for the separation of uranium isotopes by gaseous diffusion and for the separation of hydrocarbons in petrochemicals. To this end, the process under consideration is characterised in that it consists in depositing a layer of ceramic material, by hot projection, at the end of the tubular element and in sealing the end piece to the end of the tubular element by the hot projection of a ceramic or metallic substance [fr

Prediction of work piece geometry in electrochemical cavity sinking

Energy Technology Data Exchange (ETDEWEB)

Riggs, J B; Muller, R H; Tobias, C W

1981-01-01

A computer-implemented model for predicting ECM work piece geometry has been developed and experimentally verified with a commercial ECM machine for cavity sinking in copper and 302-stainless steel with 2N KNO/sub 3/ electrolyte. Constant tool piece feed rates of 7-10 x 10/sup -4/ cm/s, and applied voltages of 11-25 V were used. The model predicts the dependence of work piece geometry on operating conditions and on the electrochemical and physical properties of the metal-electrolyte pair. Comparison of eight equilibrium and six unsteady state experimental cavity profiles in copper showed satisfactory agreement with predictions, as did five equilibrium profiles for cavity sinking in 302-stainless steel.

INVESTIGATION OF SINGLE-PASS/DOUBLE-PASS TECHNIQUES ON FRICTION STIR WELDING OF ALUMINIUM

Directory of Open Access Journals (Sweden)

N.A.A. Sathari

2014-12-01

Full Text Available The aim of this research is to study the effects of single-pass/ double-pass techniques on friction stir welding of aluminium. Two pieces of AA1100 with a thickness of 6.0 mm were friction stir welded using a CNC milling machine at rotational speeds of 1400 rpm, 1600 rpm and 1800 rpm respectively for single-pass and double-pass. Microstructure observations of the welded area were studied using an optical microscope. The specimens were tested by using a tensile test and Vickers hardness test to evaluate their mechanical properties. The results indicated that, at low rotational speed, defects such as ‘surface lack of fill’ and tunnels in the welded area contributed to a decrease in mechanical properties. Welded specimens using double-pass techniques show increasing values of tensile strength and hardness. From this investigation it is found that the best parameters of FSW welded aluminium AA1100 plate were those using double-pass techniques that produce mechanically sound joints with a hardness of 56.38 HV and 108 MPa strength at 1800 rpm compared to the single-pass technique. Friction stir welding, single-pass/ double-pass techniques, AA1100, microstructure, mechanical properties.

Contrast enhancement of mail piece images

Science.gov (United States)

Shin, Yong-Chul; Sridhar, Ramalingam; Demjanenko, Victor; Palumbo, Paul W.; Hull, Jonathan J.

1992-08-01

A New approach to contrast enhancement of mail piece images is presented. The contrast enhancement is used as a preprocessing step in the real-time address block location (RT-ABL) system. The RT-ABL system processes a stream of mail piece images and locates destination address blocks. Most of the mail pieces (classified into letters) show high contrast between background and foreground. As an extreme case, however, the seasonal greeting cards usually use colored envelopes which results in reduced contrast osured by an error rate by using a linear distributed associative memory (DAM). The DAM is trained to recognize the spectra of three classes of images: with high, medium, and low OCR error rates. The DAM is not forced to make a classification every time. It is allowed to reject as unknown a spectrum presented that does not closely resemble any that has been stored in the DAM. The DAM was fairly accurate with noisy images but conservative (i.e., rejected several text images as unknowns) when there was little ground and foreground degradations without affecting the nondegraded images. This approach provides local enhancement which adapts to local features. In order to simplify the computation of A and (sigma) , dynamic programming technique is used. Implementation details, performance, and the results on test images are presented in this paper.

The smaller the pieces the healthier their consumption

DEFF Research Database (Denmark)

Hansen, Pelle Guldborg; Skov, Katrine Lund; Schmidt, Karsten

the snack breaks. The hypothesis was that consumers could be nudged to healthier food choices by improving accessibility to sliced apples and make a “healthier” cake portion (small) the default. The sample consisted of 391 people attending a congress in Copenhagen, Denmark. People were divided in two groups...... for snacking during breaks, and were informed that this was for logistic reasons. Two snack tables were set up, one with normal sized pieces of cake (usual sizes provided by the caterer) as well as whole apples (control N=189), and a table with halved pieces of cake as well as apples served in quarter pieces....... This pilot study supports the hypothesis that the presentation of snacks plays an important role in the consumption of fruit and cake among Danish adults. Further, it suggests that such approach could become a supportive tool set for achieving PHN objectives....

[Development and innovation of traditional Chinese medicine processing discipline and Chinese herbal pieces industry].

Science.gov (United States)

Xiao, Yong-Qing; Li, Li; Liu, Ying; Ma, Yin-Lian; Yu, Ding-Rong

2016-01-01

To elucidate the key issues in the development and innovation of traditional Chinese medicine processing discipline and Chinese herbal pieces industry Chinese herbal pieces industry. According to the author's accumulated experience over years and demand of the development of the Chinese herbal pieces industry, the key issues in the development and innovation on the Chinese herbal pieces industry were summarized. According to the author, the traditional Chinese medicine processing discipline shall focus on a application basis research. The development of this discipline should be closely related to the development of Chinese herbal pieces. The traditional Chinese medicine processing discipline can be improved and its results can be transformed only if this discipline were correlated with the Chinese herbal pieces industry, matched with the development of the Chinese herbal pieces industry, and solved the problems in the development on the Chinese herbal pieces industry. The development of traditional Chinese medicine processing discipline and the Chinese herbal pieces industry also requires scientific researchers to make constant innovations, realize the specialty of the researches, and innovate based on inheritance. Copyright© by the Chinese Pharmaceutical Association.

A Piece of Paper Falling Faster than Free Fall

Science.gov (United States)

Vera, F.; Rivera, R.

2011-01-01

We report a simple experiment that clearly demonstrates a common error in the explanation of the classic experiment where a small piece of paper is put over a book and the system is let fall. This classic demonstration is used in introductory physics courses to show that after eliminating the friction force with the air, the piece of paper falls…

Single Value Devices

NARCIS (Netherlands)

Mader, Angelika H.; Dertien, Edwin Christian; Reidsma, Dennis

2011-01-01

We live in a world of continuous information overflow, but the quality of information and communication is suffering. Single value devices contribute to the information and communication quality by fo- cussing on one explicit, relevant piece of information. The information is decoupled from a

Collide@CERN: exclusive open rehearsal of Gilles Jobin's last piece

CERN Multimedia

2012-01-01

Collide@CERN and Gilles Jobin, artist in residency at CERN, present an exclusive open rehearsal of his last piece SPIDER GALAXIES Tuesday 31 July 2012 - A new piece created to open new territories of the mind - Join us in Restaurant 1 from 4 p.m. (next to the Glass Box Restaurant) With this piece, the body turns into matter, which is complete, spatial and sensual. Come and see Gilles Jobin and his dancers. With a score by Cristian Vogel and Carla Scaletti invoking sound particles, while Daniel Demont disperses the spectrum. Protean, infinitely large or infinitesimal, such are the Spider Galaxies.    

A piece of paper falling faster than free fall

International Nuclear Information System (INIS)

Vera, F; Rivera, R

2011-01-01

We report a simple experiment that clearly demonstrates a common error in the explanation of the classic experiment where a small piece of paper is put over a book and the system is let fall. This classic demonstration is used in introductory physics courses to show that after eliminating the friction force with the air, the piece of paper falls with acceleration g. To test if the paper falls behind the book in a nearly free fall motion or if it is dragged by the book, we designed a version of this experiment that includes a ball and a piece of paper over a book that is forced to fall using elastic cords. We recorded a video of our experiment using a high-speed video camera at 300 frames per second that shows that the book and the paper fall faster than the ball, which falls well behind the book with an acceleration approximately equal to g. Our experiment shows that the piece of paper is dragged behind the book and therefore the paper and book demonstration should not be used to show that all objects fall with acceleration g independently of their mass.

A piece of paper falling faster than free fall

Energy Technology Data Exchange (ETDEWEB)

Vera, F; Rivera, R, E-mail: fvera@ucv.cl [Instituto de Fisica, Pontificia Universidad Catolica de ValparaIso, Av. Universidad 330, Curauma, ValparaIso (Chile)

2011-09-15

We report a simple experiment that clearly demonstrates a common error in the explanation of the classic experiment where a small piece of paper is put over a book and the system is let fall. This classic demonstration is used in introductory physics courses to show that after eliminating the friction force with the air, the piece of paper falls with acceleration g. To test if the paper falls behind the book in a nearly free fall motion or if it is dragged by the book, we designed a version of this experiment that includes a ball and a piece of paper over a book that is forced to fall using elastic cords. We recorded a video of our experiment using a high-speed video camera at 300 frames per second that shows that the book and the paper fall faster than the ball, which falls well behind the book with an acceleration approximately equal to g. Our experiment shows that the piece of paper is dragged behind the book and therefore the paper and book demonstration should not be used to show that all objects fall with acceleration g independently of their mass.

Mechanics of biopolymer materials: Single chains to bulk properties

NARCIS (Netherlands)

Amuasi, H.E.; Storm, C.

2010-01-01

We outline the first stages in the multiscale modeling of biopolymer materials, starting with the statistical mechanics of single stiff chains. In the first coarse graining step, we demonstrate how to integrate out the single polymer degrees of freedom in supramolecular assemblies of such

Introduction to solid mechanics an integrated approach

CERN Document Server

Lubliner, Jacob

2014-01-01

This textbook presents for the first time in one text the concepts and processes covered in statics and mechanics of materials curricula following a systematic, topically integrated approach. Since the turn of the millennium, it has become common in engineering schools to combine the traditional undergraduate offerings in rigid-body statics (usually called “statics”) and deformable body mechanics (known traditionally as “strength of materials” or, more recently, “mechanics of materials”) into a single, introductory course in solid mechanics. Many textbooks for the new course sequentially meld pieces of existing, discrete books—sometimes, but not always, acknowledging the origin—into two halves covering Statics and Mechanics of Materials. In this volume, Professors Lubliner and Papadopoulos methodically combine the essentials of statics and mechanics of materials, illustrating the relationship of concepts throughout, into one "integrated" text. This book also: ·         Offers thorough...

Feminist Erotica and Agency @ The Love Piece Club

OpenAIRE

DALES, Laura

2008-01-01

The Love Piece Club is a shop devoted to sex goods for women, located in Tokyo and online at www.lovepiececlub.com. As well as online shopping, the website offers regular columns, articles and photo-essays on subjects related to sexuality and women's lives. The site and shop are managed by Kitahara Minori, a writer, businesswoman and advocate for feminist erotica. This paper explores the Love Piece Club as a discursive site – its potential meanings and its significance as a feminist work in p...

Pay Matters: The Piece Rate and Health in the Developing World.

Science.gov (United States)

Davis, Mary E

Piece rate pay remains a common form of compensation in developing-world industries. While the piece rate may boost productivity, it has been shown to have unintended consequences for occupational safety and health, including increased accident and injury risk. This paper explores the relationship between worker pay and physical and emotional health, and questions the modern day business case for piece rate pay in the developing world. The relationship between piece rate and self-reported measures of physical and emotional health is estimated using a large survey of garment workers in 109 Vietnamese factories between 2010 and 2014. A random effects logit model controls for factory and year, predicting worker health as a function of pay type, demographics, and factory characteristics. Workers paid by the piece report worse physical and emotional health than workers paid by the hour (OR = 1.38-1.81). Wage incentives provide the most consistently significant evidence of all demographic and factory-level variables, including the factory's own performance on occupational safety and health compliance measures. These results highlight the importance of how workers are paid to understanding the variability in worker health outcomes. More research is needed to better understand the business case supporting the continued use of piece rate pay in the developing world. Copyright © 2016 The Author. Published by Elsevier Inc. All rights reserved.

Phonon number measurements using single photon opto-mechanics

International Nuclear Information System (INIS)

Basiri-Esfahani, S; Akram, U; Milburn, G J

2012-01-01

We describe a system composed of two coupled optical cavity modes with a coupling modulated by a bulk mechanical resonator. In addition, one of the cavity modes is irreversibly coupled to a single photon source. Our scheme is an opto-mechanical realization of the Jaynes–Cummings model where the qubit is a dual rail optical qubit while the bosonic degree of freedom is a matter degree of freedom realized as the bulk mechanical excitation. We show the possibility of engineering phonon number states of the mechanical oscillator in such a system by computing the conditional state of the mechanics after successive photon counting measurements. (paper)

Single-ion nonlinear mechanical oscillator

International Nuclear Information System (INIS)

Akerman, N.; Kotler, S.; Glickman, Y.; Dallal, Y.; Keselman, A.; Ozeri, R.

2010-01-01

We study the steady-state motion of a single trapped ion oscillator driven to the nonlinear regime. Damping is achieved via Doppler laser cooling. The ion motion is found to be well described by the Duffing oscillator model with an additional nonlinear damping term. We demonstrate here the unique ability of tuning both the linear as well as the nonlinear damping coefficients by controlling the laser-cooling parameters. Our observations pave the way for the investigation of nonlinear dynamics on the quantum-to-classical interface as well as mechanical noise squeezing in laser-cooling dynamics.

Two-piece cryopreserved tracheal allotransplantation: an experimental study.

Science.gov (United States)

Iyikesici, Tuncel; Tuncozgur, Bulent; Sanli, Maruf; Isik, Ahmet Feridun; Meteroglu, Fatih; Elbeyli, Levent

2009-10-01

For successful reconstruction with tracheal allotransplants following long tracheal resections, problems related to the preservation and vascularisation of the tracheal graft have to be solved. In this study, instead of using a long-segment single-piece graft, we used a graft that has been split into two. The aim was to use this graft after cryopreservation in order to ease neo-vascularisation and to maintain tracheal integrity by transplanting it to two separate regions of the dog cervical trachea. This experimental study was conducted in animal laboratories of the medical school on 11 half-blood dogs. The trachea obtained from the first dog was 8 cm in length; it was split into two pieces of 4 cm each and stored in the preservation solution at -80 degrees C for 4 weeks. Following this, the dog was sacrificed. Two 2 cm portions of cervical trachea were excised from the second dog. These parts were then reconstructed with two tracheal grafts of the same length as the cryopreserved ones. Ten dogs that were grouped into five groups of two dogs each underwent the same procedure. The subjects had a bronchoscopic evaluation on the third postoperative week. Anastomosis regions of the test tracheas were resected to be examined histopathologically. Seven subjects were found to have third-degree obstructions during bronchoscopy; two had close to fourth-degree obstructions. In the histopathological examination, contrary to the findings of the bronchoscopies, 75% of the anastomoses had intact epithelium. The cartilage was seen to have well-preserved structural characteristics in all the anastomoses. Twelve anastomoses had moderate, seven mild and one had severe inflammation. All anastomoses had either good or very good level of vascularisation. The integrity of the tracheal epithelium can be maintained with cryopreservation and split anastomosis technique. The cartilage preserves its structural characteristics despite losing its viability, thereby offering an advantage to

Optimization of Process Parameters During End Milling and Prediction of Work Piece Temperature Rise

Directory of Open Access Journals (Sweden)

Bhirud N.L.

2017-09-01

Full Text Available During the machining processes, heat gets generated as a result of plastic deformation of metal and friction along the tool–chip and tool–work piece interface. In materials having high thermal conductivity, like aluminium alloys, large amount of this heat is absorbed by the work piece. This results in the rise in the temperature of the work piece, which may lead to dimensional inaccuracies, surface damage and deformation. So, it is needed to control rise in the temperature of the work piece. This paper focuses on the measurement, analysis and prediction of work piece temperature rise during the dry end milling operation of Al 6063. The control factors used for experimentation were number of flutes, spindle speed, depth of cut and feed rate. The Taguchi method was employed for the planning of experimentation and L18 orthogonal array was selected. The temperature rise of the work piece was measured with the help of K-type thermocouple embedded in the work piece. Signal to noise (S/N ratio analysis was carried out using the lower-the-better quality characteristics. Depth of cut was identified as the most significant factor affecting the work piece temperature rise, followed by spindle speed. Analysis of variance (ANOVA was employed to find out the significant parameters affecting the work piece temperature rise. ANOVA results were found to be in line with the S/N ratio analysis. Regression analysis was used for developing empirical equation of temperature rise. The temperature rise of the work piece was calculated using the regression equation and was found to be in good agreement with the measured values. Finally, confirmation tests were carried out to verify the results obtained. From the confirmation test it was found that the Taguchi method is an effective method to determine optimised parameters for minimization of work piece temperature.

High-mechanical-strength single-pulse draw tower gratings

Science.gov (United States)

Rothhardt, Manfred W.; Chojetzki, Christoph; Mueller, Hans Rainer

2004-11-01

The inscription of fiber Bragg gratings during the drawing process is a very useful method to realize sensor arrays with high numbers of gratings and excellent mechanical strength and also type II gratings with high temperature stability. Results of single pulse grating arrays with numbers up to 100 and definite wavelengths and positions for sensor applications were achieved at 1550 nm and 830 nm using new photosensitive fibers developed in IPHT. Single pulse type I gratings at 1550 nm with more than 30% reflectivity were shown first time to our knowledge. The mechanical strength of this fiber with an Ormocer coating with those single pulse gratings is the same like standard telecom fibers. Weibull plots of fiber tests will be shown. At 830 nm we reached more than 10% reflectivity with single pulse writing during the fiber drawing in photosensitive fibers with less than 16 dB/km transmission loss. These gratings are useful for stress and vibration sensing applications. Type II gratings with reflectivity near 100% and smooth spectral shape and spectral width of about 1 nm are temperature stable up to 1200 K for short time. They are also realized in the fiber drawing process. These gratings are useful for temperature sensor applications.

T-piece resuscitator versus self-inflating bag for preterm resuscitation: an institutional experience.

Science.gov (United States)

Jayaram, Archana; Sima, Adam; Barker, Gail; Thacker, Leroy R

2013-07-01

Manual ventilation in the delivery room is provided with devices such as self-inflating bags (SIBs), flow-inflating bags, and T-piece resuscitators. To compare the effect of type of manual ventilation device on overall response to resuscitation among preterm neonates born at Apgar score. Secondary outcomes were incidence of air leaks, need for chest compressions/epinephrine, need for intubation, and surfactant use. We identified 294 resuscitations requiring ventilation. SIB was used for 135 neonates, and T-piece was used for 159 neonates. There was no significant difference between the 1-min and 5-min Apgar scores between SIB and T-piece (P = .77 and P = .11, respectively), nor were there significant differences in secondary outcomes. The rate of rise of Apgar score was higher, by 0.47, with T-piece, compared to SIB (95% CI 0.08-0.87, P = .02). Although some manikin studies favor T-piece for providing reliable and consistent pressures, our experience did not indicate significant differences in effectiveness of resuscitation between the T-piece and SIB in preterm resuscitations.

[Application of traditional Chinese medicine reference standards in quality control of Chinese herbal pieces].

Science.gov (United States)

Lu, Tu-Lin; Li, Jin-Ci; Yu, Jiang-Yong; Cai, Bao-Chang; Mao, Chun-Qin; Yin, Fang-Zhou

2014-01-01

Traditional Chinese medicine (TCM) reference standards plays an important role in the quality control of Chinese herbal pieces. This paper overviewed the development of TCM reference standards. By analyzing the 2010 edition of Chinese pharmacopoeia, the application of TCM reference standards in the quality control of Chinese herbal pieces was summarized, and the problems exiting in the system were put forward. In the process of improving the quality control level of Chinese herbal pieces, various kinds of advanced methods and technology should be used to research the characteristic reference standards of Chinese herbal pieces, more and more reasonable reference standards should be introduced in the quality control system of Chinese herbal pieces. This article discussed the solutions in the aspect of TCM reference standards, and future development of quality control on Chinese herbal pieces is prospected.

Coupling of single quantum emitters to plasmons propagating on mechanically etched wires

DEFF Research Database (Denmark)

Kumar, Shailesh; Huck, Alexander; Lu, Ying-Wei

2013-01-01

We demonstrate the coupling of a single nitrogen vacancy center in a nanodiamond to propagating plasmonic modes of mechanically etched silver nanowires. The mechanical etch is performed on single crystalline silver nanoplates by the tip of an atomic force microscope cantilever to produce wires...

Model Checking in Bits and Pieces

Directory of Open Access Journals (Sweden)

Kedar S. Namjoshi

2013-09-01

Full Text Available Fully automated verification of concurrent programs is a difficult problem, primarily because of state explosion: the exponential growth of a program state space with the number of its concurrently active components. It is natural to apply a divide and conquer strategy to ameliorate state explosion, by analyzing only a single component at a time. We show that this strategy leads to the notion of a "split" invariant, an assertion which is globally inductive, while being structured as the conjunction of a number of local, per-component invariants. This formulation is closely connected to the classical Owicki-Gries method and to Rely-Guarantee reasoning. We show how the division of an invariant into a number of pieces with limited scope makes it possible to apply new, localized forms of symmetry and abstraction to drastically simplify its computation. Split invariance also has interesting connections to parametric verification. A quantified invariant for a parametric system is a split invariant for every instance. We show how it is possible, in some cases, to invert this connection, and to automatically generalize from a split invariant for a small instance of a system to a quantified invariant which holds for the entire family of instances.

Mechanical design of core components for a high performance light water reactor with a three pass core

International Nuclear Information System (INIS)

Fischer, Kai; Schneider, Tobias; Redon, Thomas; Schulenberg, Thomas; Starflinger, Joerg

2007-01-01

Nuclear reactors using supercritical water as coolant can achieve more than 500 deg. C core outlet temperature, if the coolant is heated up in three steps with intermediate mixing to avoid hot streaks. This method reduces the peak cladding temperatures significantly compared with a single heat up. The paper presents an innovative mechanical design which has been developed recently for such a High Performance Light Water Reactor. The core is built with square assemblies of 40 fuel pins each, using wire wraps as grid spacers. Nine of these assemblies are combined to a cluster having a common head piece and a common foot piece. A downward flow of additional moderator water, separated from the coolant, is provided in gaps between the assemblies and in a water box inside each assembly. The cluster head and foot pieces and mixing chambers, which are key components for this design, are explained in detail. (authors)

NICHD Research Networks Help Piece Together the Puzzle of Polycystic Ovary Syndrome

Science.gov (United States)

... Print NICHD research networks help piece together the puzzle of polycystic ovary syndrome Many people think that ... more like putting together a thousand-piece jigsaw puzzle. Except that you can’t check the cover ...

Nuclear reactor fuel element containing an end piece for maintaining the column of fuel pellets

International Nuclear Information System (INIS)

Pajot, Jacques; Rabellino, Jacques.

1974-01-01

The nuclear reactor fuel element described has an end piece for maintaining the column of fuel pellets in position inside the element cladding. This end piece has a central compression spring one end of which presses against the pellets and the other against a plug shaped piece fitted with a seat for the spring, a conical piece with an elastic ring around it diverging towards the end in contact with the spring and a head at the opposite end. The connection between the compression spring and the pellets is through an application piece. A central bore provided in the end piece helps balance the pressure inside the element. This element is particularly intended for liquid metal cooled fast neutron reactors [fr

Investigation and recovery of unrecovered fuel pellets and cladding tube pieces

International Nuclear Information System (INIS)

Kobayashi, Keiji

1980-01-01

The total weight of the fuel pellets lost due to break was about 1206 g, and cladding tube pieces were about 217 g. Among these, the pellets of about 527 g and the cladding tube pieces of about 152 g were recovered when broken fuel rods were discovered. It is not desirable to leave these broken pieces as unrecovered in view of safety and the management of nuclear fuel materials. Kansai Electric Power Co., Inc., investigated the position and the amount of these pellets and cladding tube pieces for about a year, and recovered a part of them. The results were written in two reports. The objects of the investigation and recovery, and the method of recovery are explained. The UO 2 and zirconium recovered were 58.52 g and 369.58 g, respectively. The solid pellets were recovered from the reactor, fuel assemblies, a spent fuel pit and canals, and the content in sludge was recovered from other installations. The amounts of unrecovered pellets and cladding tube pieces in primary cooling water, coolant filters, sealing water filters, primary cooling pipes, waste resins and fuel assemblies were estimated. The problems concerning the recovery and estimation are pointed out. The results of estimating the amount of uranium in coolant filters and sealing water filters are useful to know the time of the occurrence of accident. (Kako, I.)

Charge collection and SEU (Single Event Upset) mechanisms

International Nuclear Information System (INIS)

Musseau, O.

1994-01-01

The purpose of this paper is to review the mechanisms of single event upset in microelectronic devices due to interaction with cosmic ions. Experimental and theoretical results are presented, and actual questions and problems are discussed. A brief introduction recalls the creation of the dense plasma of electron-hole pairs along the ion track. The basic processes for charge collection in a simple np junction (drift and diffusion) are presented. The funneling-field effect is discussed and experimental results are compared to numerical simulations and semi-empirical models. Charge collection in actual microelectronic structures is then presented. Single event upset of memory cells is discussed, based on numerical and experimental data. The main parameters for device characterization are presented. From the physical interpretation of charge collection mechanisms, the intrinsic sensitivity of various microelectronic technologies is determined and compared to experimental data. Scaling laws and future trends are discussed. (author)

Mechanism of single-frequency operation of the hybrid-CO2 laser

International Nuclear Information System (INIS)

Gondhalekar, A.; Heckenberg, N.R.; Holzhauer, E.

1975-01-01

The mechanism of a new method of obtaining high-power single-frequency pulses from a TEA-CO 2 laser is discussed. Measurements of the shape and monochromaticity of pulses from the hybrid laser which has both a TEA and a low-pressure gain section inside one resonator are presented. The mechanism of single-frequency operation of the hybrid laser is discussed with reference to numerical solutions of simplified rate equations. The low-pressure section provides gain only over a narrow range of frequencies so that a mode lying in that band-width builds up faster than neighboring modes to give a single-frequency pulse resembling in overall shape the normal TEA laser pulse. If the system is already lasing when the TEA discharge begins, the single-mode radiation already present rapidly grows to give a single-frequency pulse lacking a gain-switched peak. (U.S.)

Creep rupture of mild steel compact tension test pieces

International Nuclear Information System (INIS)

Priddle, E.K.

1978-10-01

Creep rupture lives have been determined for compact tension and unnotched tensile test pieces of mild steel at 450 0 C. Three sizes of compact tension specimens were used in which the ratios of reference stress to elastic stress intensity factor were 2.76, 4.78 and 6.6 (msup(-1/2)). The analysis of results in terms of either initial reference stress or stress intensity was unable to reduce the data to a single failure curve. An empirical correlation was found between rupture time and a reference stress/crack length combination where t = 2.46 x 10 20 sub(σref) sup(-8.96) asup(-1.56) (units hours, MPa and metres). This equation has no valid application to materials or specimens other than those from which it was derived. Reported data for 1/2Cr Mo V and 2 1/4Cr Mo steels at 565 0 C were also correlated by this approach. (author)

Piece of the sun

CERN Document Server

Wayne, Teddy

2015-01-01

Our rapidly industrialising world has an insatiable hunger for energy, and conventional sources are struggling to meet demand. Oil is running out, coal is damaging our climate, many nations are abandoning nuclear, yet solar, wind and water will never be a complete replacement. The solution, says Daniel Clery in this deeply researched and revelatory book, is to be found in the original energy source: the Sun itself. There, at its centre, the fusion of 630 million tonnes of hydrogen every second generates an unfathomable amount of energy. By replicating even a tiny piece of the Sun's power

Rehabilitation of large maxillary defect with two-piece maxillary obturators

Directory of Open Access Journals (Sweden)

Kanchan P Dholam

2015-01-01

Full Text Available The insertion and removal of an obturator in large maxillary defects with or without trismus is difficult. Fabrication of a two-piece obturator in such cases overcomes this problem. This article describes rehabilitation of large maxillary defects with two piece maxillary obturator of three types. All these obturators have a maxillary plate and a bulb component, which are approximated together by various techniques namely, silicone cover, embedded magnets, and press studs. Prosthetic rehabilitation of large maxillary defects with two-piece obturators offers the possibility of adequate oral rehabilitation by fabricating light weight prosthesis, which is easy to use. The bulb covers the undercut areas of the defect enhancing the facial contour and retention. It facilitates easy examination of underlying tissues, recreation of the anatomic barrier between the oral and nasal cavities and restoration of the function and esthetics. Thus, it adds to the quality of life.

Safety and effectiveness of a glistening-free single-piece hydrophobic acrylic intraocular lens (enVista

Directory of Open Access Journals (Sweden)

Packer M

2013-09-01

Full Text Available Mark Packer,1 Luther Fry,2 Kevin T Lavery,3 Robert Lehmann,4 James McDonald,5 Louis Nichamin,6 Brian Bearie,7,† Jon Hayashida,8 Griffith E Altmann,8 Omid Khodai8 1Department of Ophthalmology, Oregon Health and Science University, Eugene, OR, USA; 2University of Kansas Medical Center, Kansas City, KS, USA; 3Wayne State University, Detroit, MI, USA; 4Baylor College of Medicine, Houston, TX, USA; 5University of Arkansas for Medical Sciences, Little Rock, AR, USA; 6Laurel Eye Clinic, Brookville, PA, USA; 7Grand Rapids Eye Institute, Grand Rapids, MI, USA; 8Bausch & Lomb, Aliso Viejo, CA, USA †Brian Bearie passed away on March 9, 2011 Purpose: To evaluate the safety and effectiveness of a single-piece hydrophobic acrylic intraocular lens (IOL; enVista model MX60; Bausch & Lomb, Rochester, NY, USA when used to correct aphakia following cataract extraction in adults. Methods: This was a prospective case series (NCT01230060 conducted in private practices in the US. Eligible subjects were adult patients with age-related cataract amenable to treatment with standard phacoemulsification/extracapsular cataract extraction. With follow-up of 6 months, primary safety and effectiveness end points included the rates of US Food and Drug Administration (FDA-defined cumulative and persistent adverse events and the percentage of subjects who achieved best-corrected visual acuity (BCVA of 20/40 or better at final visit. To evaluate rotational stability, subjects were randomized (1:1:1:1 to have the lens implanted in one of four axis positions in 45° increments. Results: A total of 122 subjects were enrolled. The rate of cumulative and persistent adverse events did not significantly exceed historical controls, as per FDA draft guidance. At the final postoperative visit, all subjects (100% achieved a BCVA of 20/40 compared with the FDA historical control of 96.7%. Rotation of the IOL between the two final follow-up visits was ≤5° for 100% of eyes, and refractive

Exploration of mechanisms underlying the strain-rate-dependent mechanical property of single chondrocytes

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Trung Dung; Gu, YuanTong, E-mail: yuantong.gu@qut.edu.au [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland (Australia)

2014-05-05

Based on the characterization by Atomic Force Microscopy, we report that the mechanical property of single chondrocytes has dependency on the strain-rates. By comparing the mechanical deformation responses and the Young's moduli of living and fixed chondrocytes at four different strain-rates, we explore the deformation mechanisms underlying this dependency property. We found that the strain-rate-dependent mechanical property of living cells is governed by both of the cellular cytoskeleton and the intracellular fluid when the fixed chondrocytes are mainly governed by their intracellular fluid, which is called the consolidation-dependent deformation behavior. Finally, we report that the porohyperelastic constitutive material model which can capture the consolidation-dependent behavior of both living and fixed chondrocytes is a potential candidature to study living cell biomechanics.

The Effect of High Versus Low Teacher Affect and Passive Versus Active Student Activity During Music Listening on Preschool Children's Attention, Piece Preference, Time Spent Listening, and Piece Recognition.

Science.gov (United States)

Sims, Wendy L.

1986-01-01

Small-group listening lessons and subsequent individual posttests were used to judge 94 three- through five-year-old subjects' attention, paired-comparison piece preference, time spent listening, and piece recognition. Research procedures included a modified multiple baseline design and split-screen video taping of instructional sessions.…

Pathological mechanisms underlying single large‐scale mitochondrial DNA deletions

Science.gov (United States)

Rocha, Mariana C.; Rosa, Hannah S.; Grady, John P.; Blakely, Emma L.; He, Langping; Romain, Nadine; Haller, Ronald G.; Newman, Jane; McFarland, Robert; Ng, Yi Shiau; Gorman, Grainne S.; Schaefer, Andrew M.; Tuppen, Helen A.; Taylor, Robert W.

2018-01-01

Objective Single, large‐scale deletions in mitochondrial DNA (mtDNA) are a common cause of mitochondrial disease. This study aimed to investigate the relationship between the genetic defect and molecular phenotype to improve understanding of pathogenic mechanisms associated with single, large‐scale mtDNA deletions in skeletal muscle. Methods We investigated 23 muscle biopsies taken from adult patients (6 males/17 females with a mean age of 43 years) with characterized single, large‐scale mtDNA deletions. Mitochondrial respiratory chain deficiency in skeletal muscle biopsies was quantified by immunoreactivity levels for complex I and complex IV proteins. Single muscle fibers with varying degrees of deficiency were selected from 6 patient biopsies for determination of mtDNA deletion level and copy number by quantitative polymerase chain reaction. Results We have defined 3 “classes” of single, large‐scale deletion with distinct patterns of mitochondrial deficiency, determined by the size and location of the deletion. Single fiber analyses showed that fibers with greater respiratory chain deficiency harbored higher levels of mtDNA deletion with an increase in total mtDNA copy number. For the first time, we have demonstrated that threshold levels for complex I and complex IV deficiency differ based on deletion class. Interpretation Combining genetic and immunofluorescent assays, we conclude that thresholds for complex I and complex IV deficiency are modulated by the deletion of complex‐specific protein‐encoding genes. Furthermore, removal of mt‐tRNA genes impacts specific complexes only at high deletion levels, when complex‐specific protein‐encoding genes remain. These novel findings provide valuable insight into the pathogenic mechanisms associated with these mutations. Ann Neurol 2018;83:115–130 PMID:29283441

One Piece Orbitozygomatic Approach Based on the Sphenoid Ridge Keyhole

DEFF Research Database (Denmark)

Spiriev, Toma; Poulsgaard, Lars; Fugleholm, Kåre

2016-01-01

The one-piece orbitozygomatic (OZ) approach is traditionally based on the McCarty keyhole. Here, we present the use of the sphenoid ridge keyhole and its possible advantages as a keyhole for the one-piece OZ approach. Using transillumination technique the osteology of the sphenoid ridge...... was examined on 20 anatomical dry skull specimens. The results were applied to one-piece OZ approaches performed on freshly frozen cadaver heads. We defined the center of the sphenoid ridge keyhole as a superficial projection on the lateral skull surface of the most anterior and thickest part of the sphenoid...... ridge. It was located 22 mm (standard deviation [SD], 0.22 mm) from the superior temporal line; 10.7 mm (SD, 0.08 mm) posterior and 7.1 mm (SD, 0.22 mm) inferior to the frontozygomatic suture. The sphenoid ridge burr hole provides exposure of frontal, temporal dura as well as periorbita, which...

Single-Crystal Mesoporous ZnO Thin Films Composed of Nanowalls

KAUST Repository

Wang, Xudong

2009-02-05

This paper presents a controlled, large scale fabrication of mesoporous ZnO thin films. The entire ZnO mesoporous film is one piece of a single crystal, while high porosity made of nanowalls is present. The growth mechanism was proposed in comparison with the growth of ZnO nanowires. The ZnO mesoporous film was successfully applied as a gas sensor. The fabrication and growth analysis of the mesoporous ZnO thin film gi ve general guidance for the controlled growth of nanostructures. It also pro vides a unique structure with a superhigh surface-to-volume ratio for surface-related applications. © 2009 American Chemical Society.

Fully quantum-mechanical dynamic analysis of single-photon transport in a single-mode waveguide coupled to a traveling-wave resonator

International Nuclear Information System (INIS)

Hach, Edwin E. III; Elshaari, Ali W.; Preble, Stefan F.

2010-01-01

We analyze the dynamics of single-photon transport in a single-mode waveguide coupled to a micro-optical resonator by using a fully quantum-mechanical model. We examine the propagation of a single-photon Gaussian packet through the system under various coupling conditions. We review the theory of single-photon transport phenomena as applied to the system and we develop a discussion on the numerical technique we used to solve for dynamical behavior of the quantized field. To demonstrate our method and to establish robust single-photon results, we study the process of adiabatically lowering or raising the energy of a single photon trapped in an optical resonator under active tuning of the resonator. We show that our fully quantum-mechanical approach reproduces the semiclassical result in the appropriate limit and that the adiabatic invariant has the same form in each case. Finally, we explore the trapping of a single photon in a system of dynamically tuned, coupled optical cavities.

Generation of Compliant Mechanisms using Hybrid Genetic Algorithm

Science.gov (United States)

Sharma, D.; Deb, K.

2014-10-01

Compliant mechanism is a single piece elastic structure which can deform to perform the assigned task. In this work, compliant mechanisms are evolved using a constraint based bi-objective optimization formulation which requires one user defined parameter ( η). This user defined parameter limits a gap between a desired path and an actual path traced by the compliant mechanism. The non-linear and discrete optimization problems are solved using the hybrid Genetic Algorithm (GA) wherein domain specific initialization, two-dimensional crossover operator and repairing techniques are adopted. A bit-wise local search method is used with elitist non-dominated sorting genetic algorithm to further refine the compliant mechanisms. Parallel computations are performed on the master-slave architecture to reduce the computation time. A parametric study is carried out for η value which suggests a range to evolve topologically different compliant mechanisms. The applied and boundary conditions to the compliant mechanisms are considered the variables that are evolved by the hybrid GA. The post-analysis of results unveils that the complaint mechanisms are always supported at unique location that can evolve the non-dominated solutions.

Investigation of Method for Changing Impression of Musical Piece by Changing its Tempo

Science.gov (United States)

Fukumoto, Makoto; Okamatsu, Keita; Matsuo, Kazuhisa

We propose a simple method that changes impression of musical piece by changing its tempo and investigate psycho-physiological effects of the method with listening experiment. In the experiment, 8 subjects listened same musical pieces with various tempi, and analysis of heartbeat and Semantic-Differential method were used. In 6 out of 10 adjective pairs, inverted-U shapes were observed, and peak tempi of them were different. Moreover, “relaxed” evaluation might be related to listener's heart rate in rest. These results suggest possibility of constructing novel media player that changes impression of musical piece.

Two-phase flow measurements with advanced instrumented spool pieces and local conductivity probes

International Nuclear Information System (INIS)

Turnage, K.G.; Davis, C.E.

1979-01-01

A series of two-phase, air-water and steam-water tests performed with instrumented spool pieces and with conductivity probes obtained from Atomic Energy of Canada, Ltd. is described. The behavior of the three-beam densitometer, turbine meter, and drag flowmeter is discussed in terms of two-phase models. Application of some two-phase mass flow models to the recorded spool piece data is made and preliminary results are shown. Velocity and void fraction information derived from the conductivity probes is presented and compared to velocities and void fractions obtained using the spool piece instrumentation

Excitation mechanisms in singly ionized krypton laser

International Nuclear Information System (INIS)

El-Sherbini, Th.M.

1982-01-01

Lifetimes for the low lying 4p 4 4d and 4p 4 5s levels of singly ionized krypton laser are calculated, taking into account configuration interaction effects. The results show that some of these levels are metastable. They also suggest a two step excitation from the ground state of the ion (or the atom) to the upper 4p 4 5p laser levels involving some intermediate metastable states as a possible excitation mechanism. (author)

Single-source mechanical loading system produces biaxial stresses in cylinders

Science.gov (United States)

Flower, J. F.; Stafford, R. L.

1967-01-01

Single-source mechanical loading system proportions axial-to-hoop tension loads applied to cylindrical specimens. The system consists of hydraulic, pneumatic, and lever arrangements which produce biaxial loading ratios.

UTILIZATION OF STEREOLOGY FOR QUANTITATIVE ANALYSIS OF PLASTIC DEFORMATION OF FORMING PIECES

Directory of Open Access Journals (Sweden)

Maroš Martinkovič

2012-01-01

Full Text Available Mechanical working leads to final properties of forming pieces, which are affected by conditions of production technology. Utilization of stereology leads to the detail analysis of three-dimensional plastic deformed material structure by different forming technologies, e.g. forging, extruding, upsetting, metal spinning, drawing etc. The microstructure of cold drawing wires was analyzed. Grain boundaries orientation was measured on the parallel section of wire with a different degree of deformation and direct axis plastic deformation was evaluated in bulk formed part. The strain of probes on their sections was obtained using stereology by measurement of degree of grain boundary orientation which was converted to deformation using model of conversion of grain boundary orientation degree to deformation.

Application of SFM and laser scanning technology to the description of mosaics piece by piece

Directory of Open Access Journals (Sweden)

O. Ajioka

2014-06-01

Full Text Available Mosaic floors of surviving buildings in Ostia have been mainly recorded in photographs. From 2008, Japanese research group carries out a project of 3d measuring of the whole structure of ancient Roman city Ostia using laser scanners, including its landscape, city blocks, streets, buildings, wall paintings and mosaics. The laser scanner allows for a more detailed analysis and a greater potential for recording mosaics. We can record the data of mosaics, which are described piece by piece. However it is hard to acquire enough high dense point cloud and the internal camera of the laser scanner produce low quality images. We introduce a possible technology of 3D recording of mosaics with high-quality colour information; SFM. The use of this technique permits us to create 3D models from images provided from a CCD camera without heavy and large laser scanners. We applied SFM system to different three types of the mosaics laid down on the floors of "the House of the Dioscuroi", "the Insula of the Muse" and "the House of Jove and Ganymede", and created high resolution orthographic images. Then we examined to compare these orthographic images with that are created from the point cloud data. As a result, we confirmed that SFM system has sufficient practical utility for the mosaic research. And we present how much of density of point cloud or ground resolution are required for the documentation of mosaics accurately.

Strengthening mechanisms of Fe nanoparticles for single crystal Cu–Fe alloy

International Nuclear Information System (INIS)

Shi, Guodong; Chen, Xiaohua; Jiang, Han; Wang, Zidong; Tang, Hao; Fan, Yongquan

2015-01-01

A single crystal Cu–Fe alloy with finely dispersed precipitate Fe nanoparticles was fabricated in this study. The interface relationship of iron nanoparticle and copper matrix was analyzed with a high-resolution transmission electron microscope (HRTEM), and the effect of Fe nanoparticles on mechanical properties of single crystal Cu–Fe alloy was discussed. Results show that, the finely dispersed Fe nanoparticles can be obtained under the directional solidification condition, with the size of 5–50 nm and the coherent interface between the iron nanoparticle and the copper matrix. Single crystal Cu–Fe alloy possesses improved tensile strength of 194.64 MPa, and total elongation of 44.72%, respectively, at room temperature, in contrast to pure Cu sample. Nanoparticles which have coherent interface with matrix can improve the dislocation motion state. Some dislocations can slip through the nanoparticle along the coherent interface and some dislocations can enter into the nanoparticles. Thus to improve the tensile strength of single crystal Cu–Fe alloy without sacrificing the ductility simultaneously. Based on the above analyses, strengthening mechanisms of Fe nanoparticles for single crystal Cu–Fe alloy was described

Single-molecule mechanics of protein-labelled DNA handles

Directory of Open Access Journals (Sweden)

Vivek S. Jadhav

2016-01-01

Full Text Available DNA handles are often used as spacers and linkers in single-molecule experiments to isolate and tether RNAs, proteins, enzymes and ribozymes, amongst other biomolecules, between surface-modified beads for nanomechanical investigations. Custom DNA handles with varying lengths and chemical end-modifications are readily and reliably synthesized en masse, enabling force spectroscopic measurements with well-defined and long-lasting mechanical characteristics under physiological conditions over a large range of applied forces. Although these chemically tagged DNA handles are widely used, their further individual modification with protein receptors is less common and would allow for additional flexibility in grabbing biomolecules for mechanical measurements. In-depth information on reliable protocols for the synthesis of these DNA–protein hybrids and on their mechanical characteristics under varying physiological conditions are lacking in literature. Here, optical tweezers are used to investigate different protein-labelled DNA handles in a microfluidic environment under different physiological conditions. Digoxigenin (DIG-dsDNA-biotin handles of varying sizes (1000, 3034 and 4056 bp were conjugated with streptavidin or neutravidin proteins. The DIG-modified ends of these hybrids were bound to surface-modified polystyrene (anti-DIG beads. Using different physiological buffers, optical force measurements showed consistent mechanical characteristics with long dissociation times. These protein-modified DNA hybrids were also interconnected in situ with other tethered biotinylated DNA molecules. Electron-multiplying CCD (EMCCD imaging control experiments revealed that quantum dot–streptavidin conjugates at the end of DNA handles remain freely accessible. The experiments presented here demonstrate that handles produced with our protein–DNA labelling procedure are excellent candidates for grasping single molecules exposing tags suitable for molecular

Mechanical properties of hydroxyapatite single crystals from nanoindentation data

Science.gov (United States)

Zamiri, A.; De, S.

2011-01-01

In this paper we compute elasto-plastic properties of hydroxyapatite single crystals from nanindentation data using a two-step algorithm. In the first step the yield stress is obtained using hardness and Young’s modulus data, followed by the computation of the flow parameters. The computational approach is first validated with data from existing literature. It is observed that hydroxyapatite single crystals exhibit anisotropic mechanical response with a lower yield stress along the [1010] crystallographic direction compared to the [0001] direction. Both work hardening rate and work hardening exponent are found to be higher for indentation along the [0001] crystallographic direction. The stress-strain curves extracted here could be used for developing constitutive models for hydroxyapatite single crystals. PMID:21262492

Mechanical property estimation with ABI and FEM simulation

International Nuclear Information System (INIS)

Sharma, Kamal; Singh, P.K.; Das, Gautam; Bhasin, Vivek; Vaze, K.K.; Ghosh, A.K.

2007-01-01

A combined mechanical property evaluation methodology with ABI (Automated Ball Indentation) simulation and Artificial Neural Network (ANN) analysis is evolved to evaluate the mechanical properties for material. The experimental load deflection data is converted into meaningful mechanical properties for this material. An ANN database is generated with the help of contact type finite element analysis by numerically simulating the ABI process for various magnitudes of yield strength (σ yp ) (200 MPa - 500 MPa) with a range of strain hardening exponent (n) (0.1 - 0.5) and strength coefficient (K) (500 MPa - 1500 MPa). For the present problem, a ball indenter of 1.57 mm diameter having Young's modulus approximately 100 times more than the test piece is used to minimize the error due to indenter deformation. Test piece dimension is kept large enough in comparison to the indenter configuration in the simulation to minimize the deflection at the outer edge of the test piece. Further this database after the neural network training; is used to analyze measured material properties of different test pieces. The ANN predictions are reconfirmed with contact type finite element analysis for an arbitrary selected test sample. The methodology evolved in this work can be extended to predict material properties for any irradiated nuclear material in the service. (author)

A new approach of quantum mechanics for neutron single-slit diffraction

International Nuclear Information System (INIS)

Wu Xiangyao; Yang Jinghai; Liu Xiaojing; Wang Li; Liu Bing; Fan Xihui; Guo Yiqing

2007-01-01

Phenomena of electron, neutron, atomic and molecular diffraction have been studied in many experiments, and these experiments are explained by many theoretical works. We study neutron single-slit diffraction with a quantum mechanical approach. It is found that the obvious diffraction patterns can be obtained when the single slit width a is in the range of 3λ-60λ. We also find a new quantum effect of the thickness of single-slit which can make a large impact on the diffraction pattern. The new quantum effect predicted in our work can be tested by the neutron single-slit diffraction experiment. (authors)

Quasi free mechanism in single photon double ionization of helium

Energy Technology Data Exchange (ETDEWEB)

Schoeffler, Markus; Stuck, Christian [Frankfurt Univ., Frankfurt am Main (Germany). Inst. fuer Kernphysik; Lawrence Berkeley National Lab, Berkeley, CA (United States); Jahnke, Till; Waitz, Markus; Trinter, Florian; Lenz, Ute; Schmidt-Boecking, Horst; Doerner, Reinhard [Frankfurt Univ., Frankfurt am Main (Germany). Inst. fuer Kernphysik; Jones, Mathew; Landers, Allen [Auburn University, Auburn, AL (United States); Belkacem, Ali; Weber, Thorsten [Lawrence Berkeley National Lab, Berkeley, CA (United States); Cocke, Lew [Kansas State University, Manhattan, KS (United States)

2012-07-01

Double ionization of Helium by a single photon is widely believed to proceed through two mechanisms: knock-off (TS1) or shake-off, with the last one dominating at high photon energies. A new mechanism, termed ''Quasi Free Mechanism'' (QFM) was predicted 35 years ago by Amusia and coworkers, but escaped experimental observation till today. Here we provide the first proof of this mechanism using 800 eV photons from the Advanced Light Source. Fragments (electrons and ions) were measured in coincidence using momentum spectroscopy (COLTRIMS). He{sup (}2+) ions with zero momentum were found - the fingerprint for the QFM.

Short- and Long-Term Musical Preferences: What Makes a Favourite Piece of Music?

Science.gov (United States)

Lamont, Alexandra; Webb, Rebecca

2010-01-01

Within the growing field of music preferences, little is currently known about the concept of a favourite piece of music. The current study explores listeners' nominated favourite pieces of music over short and longer time-spans, combining diary and interview methods to uncover what a favourite means, how stable it is, and what factors influence…

Development of debris-resistant bottom end piece

International Nuclear Information System (INIS)

Sohn, Dong Seong; Lee, Jae Kyung; Hwang, Dae Hyun; Yim, Jung Sik; Song, Kee Nam; Oh, Dong Seok; Im, Hyun Tae

1993-01-01

Debris-related fuel failures has been identified to be one of the major causes of fuel failures recently occured in nuclear power plants. In order to reduce the possibility of debris-related fuel failures, it is necessary to prevent the debris from reaching to fuel rods. In this regard, it is important to develop Debris-Resistant Bottom End Piece. (Author)

Mechanics of single-walled carbon nanotubes inside open single-walled carbon nanocones

International Nuclear Information System (INIS)

Ansari, R.; Hosseinzadeh, M.

2013-01-01

This study investigates the mechanical characteristics of single-walled carbon nanotubes (CNTs) inside open single-walled carbon nanocones (CNCs). New semi-analytical expressions are presented to evaluate van der Waals (vdW) interactions between CNTs and open CNCs. Continuum approximation, along with the the Lennard-Jones (LJ) potential function, is used in this study. The effects of geometrical parameters on alterations in vdW potential energy and the interaction force are extensively examined for the concentric CNT-open CNC configuration. The CNT is assumed to enter the nanocone either through the small end or the wide end of the cone. The preferred position of the CNT with respect to the nanocone axis is fully investigated for various geometrical parameters. The optimum nanotube radius minimizing the total potential energy of the concentric configuration is determined for different radii of the small end of the cone. The examined configuration generates asymmetric oscillation; thus, the system constitutes a nano-oscillator.

Single Point Incremental Forming using a Dummy Sheet

DEFF Research Database (Denmark)

Skjødt, Martin; Silva, Beatriz; Bay, Niels

2007-01-01

A new version of single point incremental forming (SPIF) is presented. This version includes a dummy sheet on top of the work piece, thus forming two sheets instead of one. The dummy sheet, which is in contact with the rotating tool pin, is discarded after forming. The new set-up influences....... The possible influence of friction between the two sheets is furthermore investigated. The results show that the use of a dummy sheet reduces wear of the work piece to almost zero, but also causes a decrease in formability. Bulging of the planar sides of the pyramid is reduced and surface roughness...

Manufacturing and thermomechanical testing of actively cooled all beryllium high heat flux test pieces

International Nuclear Information System (INIS)

Vasiliev, N.N.; Sokolov, Yu.A.; Shatalov, G.E.

1995-01-01

One of the problems affiliated to ITER high heat flux elements development is a problem of interface of beryllium protection with heat sink routinely made of copper alloys. To get rid of this problem all beryllium elements could be used as heat receivers in places of enhanced thermal loads. In accordance with this objectives four beryllium test pieces of two types have been manufactured in open-quotes Institute of Berylliumclose quotes for succeeding thermomechanical testing. Two of them were manufactured in accordance with JET team design; they are round open-quotes hypervapotron typeclose quotes test pieces. Another two ones are rectangular test sections with a twisted tape installed inside of the circular channel. Preliminary stress-strain analysis have been performed for both type of the test pieces. Hypervapotrons have been shipped to JET where they were tested on JET test bed. Thermomechanical testing of pieces of the type of open-quotes swirl tape inside of tubeclose quotes have been performed on Kurchatov Institute test bed. Chosen beryllium grade properties, some details of manufacturing, results of preliminary stress-strain analysis and thermomechanical testing of the test pieces open-quotes swirl tape inside of tubeclose quotes type are given in this report

Note onset deviations as musical piece signatures.

Science.gov (United States)

Serrà, Joan; Özaslan, Tan Hakan; Arcos, Josep Lluis

2013-01-01

A competent interpretation of a musical composition presents several non-explicit departures from the written score. Timing variations are perhaps the most important ones: they are fundamental for expressive performance and a key ingredient for conferring a human-like quality to machine-based music renditions. However, the nature of such variations is still an open research question, with diverse theories that indicate a multi-dimensional phenomenon. In the present study, we consider event-shift timing variations and show that sequences of note onset deviations are robust and reliable predictors of the musical piece being played, irrespective of the performer. In fact, our results suggest that only a few consecutive onset deviations are already enough to identify a musical composition with statistically significant accuracy. We consider a mid-size collection of commercial recordings of classical guitar pieces and follow a quantitative approach based on the combination of standard statistical tools and machine learning techniques with the semi-automatic estimation of onset deviations. Besides the reported results, we believe that the considered materials and the methodology followed widen the testing ground for studying musical timing and could open new perspectives in related research fields.

Note onset deviations as musical piece signatures.

Directory of Open Access Journals (Sweden)

Joan Serrà

Full Text Available A competent interpretation of a musical composition presents several non-explicit departures from the written score. Timing variations are perhaps the most important ones: they are fundamental for expressive performance and a key ingredient for conferring a human-like quality to machine-based music renditions. However, the nature of such variations is still an open research question, with diverse theories that indicate a multi-dimensional phenomenon. In the present study, we consider event-shift timing variations and show that sequences of note onset deviations are robust and reliable predictors of the musical piece being played, irrespective of the performer. In fact, our results suggest that only a few consecutive onset deviations are already enough to identify a musical composition with statistically significant accuracy. We consider a mid-size collection of commercial recordings of classical guitar pieces and follow a quantitative approach based on the combination of standard statistical tools and machine learning techniques with the semi-automatic estimation of onset deviations. Besides the reported results, we believe that the considered materials and the methodology followed widen the testing ground for studying musical timing and could open new perspectives in related research fields.

A three-dimensional analysis of fracture mechanics test pieces of different geometries part 2 - Constraint and material variations

Energy Technology Data Exchange (ETDEWEB)

Tkach, Y., E-mail: Yuri.Tkach@WGIM.com [Department of Civil and Structural Engineering, School of MACE, UMIST/University of Manchester, PO Box 88, Manchester M60 1QD (United Kingdom); Burdekin, F.M., E-mail: mburdekin@aol.com [Department of Civil and Structural Engineering, School of MACE, UMIST/University of Manchester, PO Box 88, Manchester M60 1QD (United Kingdom)

2012-05-15

This paper reports the second stage of an extensive series of detailed three-dimensional elastic-plastic finite element analyses on the influence of fracture mechanics test specimen geometry and different material properties on constraint and triaxiality in the near crack tip region. The specimens studied were pre-cracked plain-sided and side-grooved Charpy sized specimens, plain-sided and side-grooved compact tension specimens of thickness B = 25 mm and plain-sided compact tension specimens of thickness B = 100 mm all with the ratio of the crack length to the specimen width a/W = 0.5. Stress-strain curves of materials of different yield strength and strain hardening behaviour spanning the range of practical interest for typical structural steels were implemented into the finite element models. The level of constraint in the specimens modelled has been characterised in terms of both the Q-stress parameter and the ratio of hydrostatic to the equivalent stress components. It has been established that in-plane constraint in the fracture toughness test pieces is significantly affected by the absolute ligament size of the specimen. It has also been shown that the strain hardening behaviour is one of the major material parameters defining constraint level in the fracture toughness specimen. - Highlights: Black-Right-Pointing-Pointer 3D FE analyses on plain and side-grooved Charpy sized and CT specimens of two sizes. Black-Right-Pointing-Pointer Crack tip constraint analysed for Q-stress and hydrostatic/equivalent stress ratio. Black-Right-Pointing-Pointer In-plane constraint is significantly affected by the absolute ligament size. Black-Right-Pointing-Pointer Constraint level is significantly affected by material strain hardening behaviour.

A three-dimensional analysis of fracture mechanics test pieces of different geometries part 2 - Constraint and material variations

International Nuclear Information System (INIS)

Tkach, Y.; Burdekin, F.M.

2012-01-01

This paper reports the second stage of an extensive series of detailed three-dimensional elastic-plastic finite element analyses on the influence of fracture mechanics test specimen geometry and different material properties on constraint and triaxiality in the near crack tip region. The specimens studied were pre-cracked plain-sided and side-grooved Charpy sized specimens, plain-sided and side-grooved compact tension specimens of thickness B = 25 mm and plain-sided compact tension specimens of thickness B = 100 mm all with the ratio of the crack length to the specimen width a/W = 0.5. Stress–strain curves of materials of different yield strength and strain hardening behaviour spanning the range of practical interest for typical structural steels were implemented into the finite element models. The level of constraint in the specimens modelled has been characterised in terms of both the Q-stress parameter and the ratio of hydrostatic to the equivalent stress components. It has been established that in-plane constraint in the fracture toughness test pieces is significantly affected by the absolute ligament size of the specimen. It has also been shown that the strain hardening behaviour is one of the major material parameters defining constraint level in the fracture toughness specimen. - Highlights: ► 3D FE analyses on plain and side-grooved Charpy sized and CT specimens of two sizes. ► Crack tip constraint analysed for Q-stress and hydrostatic/equivalent stress ratio. ► In-plane constraint is significantly affected by the absolute ligament size. ► Constraint level is significantly affected by material strain hardening behaviour.

Operation analysis of a Chebyshev-Pantograph leg mechanism for a single DOF biped robot

Science.gov (United States)

Liang, Conghui; Ceccarelli, Marco; Takeda, Yukio

2012-12-01

In this paper, operation analysis of a Chebyshev-Pantograph leg mechanism is presented for a single degree of freedom (DOF) biped robot. The proposed leg mechanism is composed of a Chebyshev four-bar linkage and a pantograph mechanism. In contrast to general fully actuated anthropomorphic leg mechanisms, the proposed leg mechanism has peculiar features like compactness, low-cost, and easy-operation. Kinematic equations of the proposed leg mechanism are formulated for a computer oriented simulation. Simulation results show the operation performance of the proposed leg mechanism with suitable characteristics. A parametric study has been carried out to evaluate the operation performance as function of design parameters. A prototype of a single DOF biped robot equipped with two proposed leg mechanisms has been built at LARM (Laboratory of Robotics and Mechatronics). Experimental test shows practical feasible walking ability of the prototype, as well as drawbacks are discussed for the mechanical design.

Advanced Prop-fan Engine Technology (APET) single- and counter-rotation gearbox/pitch change mechanism

Science.gov (United States)

Reynolds, C. N.

1985-01-01

The preliminary design of advanced technology (1992) turboprop engines for single-rotation prop-fans and conceptual designs of pitch change mechanisms for single- and counter-rotation prop-fan application are discussed. The single-rotation gearbox is a split path, in-line configuration. The counter-rotation gearbox is an in-line, differential planetary design. The pitch change mechanisms for both the single- and counter-rotation arrangements are rotary/hydraulic. The advanced technology single-rotation gearbox yields a 2.4 percent improvement in aircraft fuel burn and a one percent improvement in operating cost relative to a current technology gearbox. The 1992 counter-rotation gearbox is 15 percent lighter, 15 percent more reliable, 5 percent lower in cost, and 45 percent lower in maintenance cost than the 1992 single-rotation gearbox. The pitch controls are modular, accessible, and external.

Parameter study of temperature distribution in a work-piece during dry hyperbaric GTA-welding

International Nuclear Information System (INIS)

Fulfs, H.

1989-01-01

In a sensitivity study the influence of initial and boundary welding parameters upon the spatial and temporal temperature distribution in a work-piece during dry hyperbaric GTA-welding is investigated. It will be shown that at constant arc current a variation of pressure (1-60 bar), arc length (3-10 mm), welding speed (1-2.5 mm/s) or the initial temperature (20-200deg C) of the work-piece to some extend significantly influences the size of melt and heat affected zone as well as the maximum temperature and cooling behaviour of the work-piece; compared to this no mentionable effects of shielding gas temperature (20-300deg C) or flow rate (10-500 dm N 3 /min) on the thermal condition of the work-piece can be recognized. The discovered relationships have been approximated by simple correlations, which can be used for parameter optimization and process control. (orig.) With 33 figs., 4 tabs [de

Influence of alloy elements on physical and mechanical properties of single crystalline austenitic stainless steels

International Nuclear Information System (INIS)

Okamoto, Kazutaka; Kaneda, Junya; Yoshinari, Akira; Aono, Yasuhisa

2000-01-01

The single crystalline austenitic stainless steels based on 316 L were developed to improve their resistance to intergranular corrosion and stress corrosion cracking. However the mechanical properties of the single crystals were lower than those of polycrystalline. The precipitation hardening methods were applied to the single crystal for the increase of their mechanical strength by addition of niobium and heat treatments. In this paper, the influences of niobium concentration on the several physical and mechanical properties of these single crystalline austenitic stainless steels were studied. The thermal conductivity, coefficients of thermal expansion and elastic constants of the single crystals were almost the same as those of polycrystalline independently of the niobium concentration. The mechanical properties of the single crystals strongly depended on the niobium concentration and the orientation. In the specimen which contains 1.0 mass% niobium, 0.2% proof stress were remarkably improved; 370 MPa, 337 MPa and 403 MPa were obtained in , and orientations at the room temperature. The creep rupture strength and the high cycle fatigue strength were also improved by addition of niobium. In the -orientated specimen which contains 1.0 mass% niobium, the creep rupture strength at 873 K for 103 hours, 245 MPa and the high cycle fatigue strength at 773 K for 107 cycles, 220 MPa were obtained. Furthermore, the single crystalline pipe, bolts and nuts were successfully manufactured for the application of these single crystals. (author)

Double-slit experiment with single wave-driven particles and its relation to quantum mechanics.

Science.gov (United States)

Andersen, Anders; Madsen, Jacob; Reichelt, Christian; Rosenlund Ahl, Sonja; Lautrup, Benny; Ellegaard, Clive; Levinsen, Mogens T; Bohr, Tomas

2015-07-01

In a thought-provoking paper, Couder and Fort [Phys. Rev. Lett. 97, 154101 (2006)] describe a version of the famous double-slit experiment performed with droplets bouncing on a vertically vibrated fluid surface. In the experiment, an interference pattern in the single-particle statistics is found even though it is possible to determine unambiguously which slit the walking droplet passes. Here we argue, however, that the single-particle statistics in such an experiment will be fundamentally different from the single-particle statistics of quantum mechanics. Quantum mechanical interference takes place between different classical paths with precise amplitude and phase relations. In the double-slit experiment with walking droplets, these relations are lost since one of the paths is singled out by the droplet. To support our conclusions, we have carried out our own double-slit experiment, and our results, in particular the long and variable slit passage times of the droplets, cast strong doubt on the feasibility of the interference claimed by Couder and Fort. To understand theoretically the limitations of wave-driven particle systems as analogs to quantum mechanics, we introduce a Schrödinger equation with a source term originating from a localized particle that generates a wave while being simultaneously guided by it. We show that the ensuing particle-wave dynamics can capture some characteristics of quantum mechanics such as orbital quantization. However, the particle-wave dynamics can not reproduce quantum mechanics in general, and we show that the single-particle statistics for our model in a double-slit experiment with an additional splitter plate differs qualitatively from that of quantum mechanics.

Double-slit experiment with single wave-driven particles and its relation to quantum mechanics

Science.gov (United States)

Andersen, Anders; Madsen, Jacob; Reichelt, Christian; Rosenlund Ahl, Sonja; Lautrup, Benny; Ellegaard, Clive; Levinsen, Mogens T.; Bohr, Tomas

2015-07-01

In a thought-provoking paper, Couder and Fort [Phys. Rev. Lett. 97, 154101 (2006), 10.1103/PhysRevLett.97.154101] describe a version of the famous double-slit experiment performed with droplets bouncing on a vertically vibrated fluid surface. In the experiment, an interference pattern in the single-particle statistics is found even though it is possible to determine unambiguously which slit the walking droplet passes. Here we argue, however, that the single-particle statistics in such an experiment will be fundamentally different from the single-particle statistics of quantum mechanics. Quantum mechanical interference takes place between different classical paths with precise amplitude and phase relations. In the double-slit experiment with walking droplets, these relations are lost since one of the paths is singled out by the droplet. To support our conclusions, we have carried out our own double-slit experiment, and our results, in particular the long and variable slit passage times of the droplets, cast strong doubt on the feasibility of the interference claimed by Couder and Fort. To understand theoretically the limitations of wave-driven particle systems as analogs to quantum mechanics, we introduce a Schrödinger equation with a source term originating from a localized particle that generates a wave while being simultaneously guided by it. We show that the ensuing particle-wave dynamics can capture some characteristics of quantum mechanics such as orbital quantization. However, the particle-wave dynamics can not reproduce quantum mechanics in general, and we show that the single-particle statistics for our model in a double-slit experiment with an additional splitter plate differs qualitatively from that of quantum mechanics.

One-Piece Faraday Generator: A Paradoxical Experiment from 1851

Science.gov (United States)

Crooks, M. J.; And Others

1978-01-01

Describes an experiment based on Faraday's one-piece generator, where the rotating disk is replaced by a cylindrical permanent magnet. Explains the apparent paradox that an observer in an inertial frame could measure his absolute velocity. (GA)

Swiveling Lathe Jaw Concept for Holding Irregular Pieces

Science.gov (United States)

David, J.

1966-01-01

Clamp holds irregularly shaped pieces in lathe chuck without damage and eliminates excessive time in selecting optimum mounting. Interchangeable jaws ride in standard jaw slots but swivel so that the jaw face bears evenly against the workpiece regardless of contour. The jaws can be used on both engine and turret lathes.

Different Digitalization Techniques for 3D Printing of Anatomical Pieces.

Science.gov (United States)

Ugidos Lozano, M T; Blaya Haro, F; Ruggiero, Alessandro; Manzoor, S; Nuere Menendez-Pidal, S; Juanes Méndez, J A

2018-01-25

The use of different technological devices that allow the creation of three-dimensional models is in constant evolution, allowing a greater application of these technologies in different fields of health sciences and medical training. The equipment for digitalization is becoming increasingly sophisticated allowing obtaining three-dimensional which are more defined and similar to real image and original object. In this work, different modalities of designing 3D anatomical models of bone pieces are presented, for use by students of different disciplines in Health Sciences. To do this we digitalized bone pieces, with different models of scanners, producing images that can be transformed for 3D printing, with a Colido X 3045 printer by digital treatment with different software.

Controlled switching of single-molecule junctions by mechanical motion of a phenyl ring

Directory of Open Access Journals (Sweden)

Yuya Kitaguchi

2015-10-01

Full Text Available Mechanical methods for single-molecule control have potential for wide application in nanodevices and machines. Here we demonstrate the operation of a single-molecule switch made functional by the motion of a phenyl ring, analogous to the lever in a conventional toggle switch. The switch can be actuated by dual triggers, either by a voltage pulse or by displacement of the electrode, and electronic manipulation of the ring by chemical substitution enables rational control of the on-state conductance. Owing to its simple mechanics, structural robustness, and chemical accessibility, we propose that phenyl rings are promising components in mechanical molecular devices.

Binding energy and mechanical stability of single- and multi-walled carbon nanotube serpentines

International Nuclear Information System (INIS)

Zhao, Junhua; Lu, Lixin; Rabczuk, Timon

2014-01-01

Recently, Geblinger et al. [Nat. Nanotechnol. 3, 195 (2008)] and Machado et al. [Phys. Rev. Lett. 110, 105502 (2013)] reported the experimental and molecular dynamics realization of S-like shaped single-walled carbon nanotubes (CNTs), the so-called CNT serpentines. We reported here results from continuum modeling of the binding energy γ between different single- and multi-walled CNT serpentines and substrates as well as the mechanical stability of the CNT serpentine formation. The critical length for the mechanical stability and adhesion of different CNT serpentines are determined in dependence of E i I i , d, and γ, where E i I i and d are the CNT bending stiffness and distance of the CNT translation period. Our continuum model is validated by comparing its solution to full-atom molecular dynamics calculations. The derived analytical solutions are of great importance for understanding the interaction mechanism between different single- and multi-walled CNT serpentines and substrates

One piece reactor removal

International Nuclear Information System (INIS)

Chia, Wei-Min; Wang, Song-Feng

1993-01-01

The strategy of Taiwan Research Reactor Renewal plan is to remove the old reactor block with One Piece Reactor Removal (OPRR) method for installing a new research reactor in original building. In this paper, the engineering design of each transportation works including the work method, the major equipments, the design policy and design criteria is described and discussed. In addition, to ensure the reactor block is safety transported for storage and to guarantee the integrity of reactor base mat is maintained for new reactor, operation safety is drawn special attention, particularly under seismic condition, to warrant safe operation of OPRR. ALARA principle and Below Regulatory Concern (BRC) practice were also incorporated in the planning to minimize the collective dose and the total amount of radioactive wastes. All these activities are introduced in this paper. (J.P.N.)

Nano-Electromechanical Systems: Displacement Detection and the Mechanical Single Electron Shuttle

Science.gov (United States)

Blick, R. H.; Beil, F. W.; Höhberger, E.; Erbe, A.; Weiss, C.

For an introduction to nano-electromechanical systems we present measurements on nanomechanical resonators operating in the radio frequency range. We discuss in detail two different schemes of displacement detection for mechanical resonators, namely conventional reflection measurements of a probing signal and direct detection by capacitive coupling via a gate electrode. For capacitive detection we employ an on-chip preamplifier, which enables direct measurements of the resonator's disp lacement. We observe that the mechanical quality factor of the resonator depends on the detection technique applied, which is verified in model calculations and report on the detection of sub-harmonics. In the second part we extend our investigations to include transport of single electrons through an electron island on the tip of a nanomachined mechanical pendulum. The pendulum is operated by applying a modulating electromagnetic field in the range of 1 - 200 MHz, leading to mechanical oscillations between two laterally integrated source and drain contacts. Forming tunneling barriers the metallic tip shuttles single electrons from source to drain. The resulting tunneling current shows distinct features corresponding to the discrete mechanical eigenfrequencies of the pendulum. We report on measurements covering the temperature range from 300 K down to 4.2 K. The transport properties of the device are compared in detail to model calculations based on a Master-equation approach.

Chemo-mechanical pushing of proteins along single-stranded DNA.

Science.gov (United States)

Sokoloski, Joshua E; Kozlov, Alexander G; Galletto, Roberto; Lohman, Timothy M

2016-05-31

Single-stranded (ss)DNA binding (SSB) proteins bind with high affinity to ssDNA generated during DNA replication, recombination, and repair; however, these SSBs must eventually be displaced from or reorganized along the ssDNA. One potential mechanism for reorganization is for an ssDNA translocase (ATP-dependent motor) to push the SSB along ssDNA. Here we use single molecule total internal reflection fluorescence microscopy to detect such pushing events. When Cy5-labeled Escherichia coli (Ec) SSB is bound to surface-immobilized 3'-Cy3-labeled ssDNA, a fluctuating FRET signal is observed, consistent with random diffusion of SSB along the ssDNA. Addition of Saccharomyces cerevisiae Pif1, a 5' to 3' ssDNA translocase, results in the appearance of isolated, irregularly spaced saw-tooth FRET spikes only in the presence of ATP. These FRET spikes result from translocase-induced directional (5' to 3') pushing of the SSB toward the 3' ssDNA end, followed by displacement of the SSB from the DNA end. Similar ATP-dependent pushing events, but in the opposite (3' to 5') direction, are observed with EcRep and EcUvrD (both 3' to 5' ssDNA translocases). Simulations indicate that these events reflect active pushing by the translocase. The ability of translocases to chemo-mechanically push heterologous SSB proteins along ssDNA provides a potential mechanism for reorganization and clearance of tightly bound SSBs from ssDNA.

Performance-Based Design Optimization of a Transition Piece for Bucket Foundations for Offshore Wind Turbines

DEFF Research Database (Denmark)

Nezhentseva, Anastasia; Andersen, Lars; Ibsen, Lars Bo

2011-01-01

This paper deals with optimization of the shape of the transition piece connecting turbine column with a suction bucket used as a monopod foundation for an offshore wind turbine. The structural behaviour of a transition piece made of compact reinforced composite (CRC) is analysed. Several...

Archaeological analogous and industrials for deep storage: study of the archaeological metallic piece

International Nuclear Information System (INIS)

Criado Portal, A. J.; Martinez Garcia, J. A.; Calabres Molina, R.; Garcia abajo, A.; Penco Valenzuela, F.; Lecanda Esteban, J. A.; Garcia Bartual, M.; Jimenez Gonzalez, J. M.; Bravo Munoz, E.; Rodriguez Lobo, L. M.; Fernandez Cascos, T.; Fernandes Cordero, O.; Montero Ruiz, I.

2000-01-01

The aim of present research is to obtain information about archaeological analogous of iron and steel, useful for the model of deep geological repository (AGP). The analogous examined have remained buried between 1400 and 2400 years, in very assorted geochemical environments. The extraction of the archaeological pieces has been accomplished according to normalised protocols, trying to carry to the laboratory so the piece as its burial environment, avoiding all possible pollution. Trying to the archaeological analogous could provide valuable information to the AGP model, the study has been directed to related the physical-chemical characteristics of the terrain respect to the deterioration of the archaeological metallic piece. The geology of the surrounding terrain to the archaeological deposit, the geomorphological study of the terrain and data from the analysis of ground: pH, wetness, porosity, organic matter contents, bacteria presence, sulphates, carbonates, chlorides, etc., have allowed to explain the physical-chemical phenomena suffered by the archaeological iron and steel pieces. Also, an exhaustive study of the archaeological piece has been accomplished, concerning the microstructure of the corrosion layer and of the not deteriorated metallic rest. Obtained information concerns different items, such as corrosion velocity and formations of oxide layers, diffusion of chemical elements from the corrosion layer to the metal and viceversa, and structural changes in oxide layers and in the metallic remains by structural ageing. Obtained data have allowed to develop a mathematical model for calculation of corrosion velocity in buried iron and steels, based on physical-chemical variables of grounds, chemical composition and thermomechanical treatment given to the metal during its manufacture. (Author)

Force spectroscopy studies on protein-ligand interactions: a single protein mechanics perspective.

Science.gov (United States)

Hu, Xiaotang; Li, Hongbin

2014-10-01

Protein-ligand interactions are ubiquitous and play important roles in almost every biological process. The direct elucidation of the thermodynamic, structural and functional consequences of protein-ligand interactions is thus of critical importance to decipher the mechanism underlying these biological processes. A toolbox containing a variety of powerful techniques has been developed to quantitatively study protein-ligand interactions in vitro as well as in living systems. The development of atomic force microscopy-based single molecule force spectroscopy techniques has expanded this toolbox and made it possible to directly probe the mechanical consequence of ligand binding on proteins. Many recent experiments have revealed how ligand binding affects the mechanical stability and mechanical unfolding dynamics of proteins, and provided mechanistic understanding on these effects. The enhancement effect of mechanical stability by ligand binding has been used to help tune the mechanical stability of proteins in a rational manner and develop novel functional binding assays for protein-ligand interactions. Single molecule force spectroscopy studies have started to shed new lights on the structural and functional consequence of ligand binding on proteins that bear force under their biological settings. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Investigating and Improving Student Understanding of Quantum Mechanics in the Context of Single Photon Interference

Science.gov (United States)

Marshman, Emily; Singh, Chandralekha

2017-01-01

Single photon experiments involving a Mach-Zehnder interferometer can illustrate the fundamental principles of quantum mechanics, e.g., the wave-particle duality of a single photon, single photon interference, and the probabilistic nature of quantum measurement involving single photons. These experiments explicitly make the connection between the…

Double-slit experiment with single wave-driven particles and its relation to quantum mechanics

DEFF Research Database (Denmark)

Andersen, Anders Peter; Madsen, Jacob; Reichelt, Christian Günther

2015-01-01

even though it is possible to determine unambiguously which slit the walking droplet passes. Here we argue, however, that the single-particle statistics in such an experiment will be fundamentally different from the single-particle statistics of quantum mechanics. Quantum mechanical interference takes...... place between different classical paths with precise amplitude and phase relations. In the double-slit experiment with walking droplets, these relations are lost since one of the paths is singled out by the droplet. To support our conclusions, we have carried out our own double-slit experiment, and our...... results, in particular the long and variable slit passage times of the droplets, cast strong doubt on the feasibility of the interference claimed by Couder and Fort. To understand theoretically the limitations of wave-driven particle systems as analogs to quantum mechanics, we introduce a Schro...

A study for the improvement of top end piece structure strength

International Nuclear Information System (INIS)

Song, Kee Nam; Sohn, Dong Seong

1989-01-01

As a part of the top end piece(TEP) for the 14 X 14 reload fuel, various models of top end piece structure were analysed, using the ANSYS code, under fuel assembly shipping and handling load conditions. The 3-dimensional isoparametric elements were used in each model. By rearrangement of slots and holes on the adapter plate, without violating the design requirements, and also by changing the enclosure attachment method used on the adapter plate from pin joints to through-weld, the load carrying capacity of the adapter plate was greatly strengthened. These concepts were adopted for the design of the 14 X 14 reload fuel. (Author)

Nzikitanza – A piece on the resistance against the MUOS in Niscemi , Sicily

Directory of Open Access Journals (Sweden)

Marcello Messina

2015-12-01

Full Text Available Nzikitanza for accordion, violin, cello and tape was written in 2012 as a reflection on the deployment of Sicilian territory for NATO and US military operations. In particular, the piece was inspired by the then newly formed resistance committee against the MUOS in Niscemi. This brief commentary will illustrate a priori and a posteriori reflections on the status of the piece as a contribution to forms of antagonistic culture.

Real-time imaging systems for superconducting nanowire single-photon detector arrays

Energy Technology Data Exchange (ETDEWEB)

Hofherr, Matthias

2014-07-01

Superconducting nanowire singe-photon detectors (SNSPD) are promising detectors in the field of applications, where single-photon resolution is required like in quantum optics, spectroscopy or astronomy. These cryogenic detectors gain from a broad spectrum in the optical and infrared range and deliver low dark counts and low jitter. This work provides a piece of deeper physical understanding of detector functionality in combination with highly engineered readout development. A detailed analysis focuses on the intrinsic detection mechanism of SNSPDs related to the detection in the infrared regime and the evolution of dark counts. With this fundamental knowledge, the next step is the development of a multi-pixel readout at cryogenic conditions. It is demonstrated, how two auspicious multi-pixel readout concepts can be realized, which enables statistical framing like in imaging applications using RSFQ electronics with fast framing rates and the readout of a detector array with continuous real-time single-photon resolution.

Inspection of complex geometry pieces with an intelligent contact transducer

International Nuclear Information System (INIS)

Chatillon, S.; Roy, O.; Mahaut, St.

2000-01-01

A new multi-element contact transducer has been developed to improve the inspection of components with complex geometry. The emitting surface is flexible in order to optimize the contact with pieces. An algorithm, based on a simplified geometric model, has been used to determine the delays law which allows to control the focal characteristics of the transmitted field. Acquisition data lead in transmission with an articulated transducer validate the behavior provided by simulation. Thus the optimization of the delays law ensures the transmission of a beam which is homogeneous and controlled during the moving of the transducer. Inspections in echo-pulse mode are implemented on a sample simulating a component controlled on site. Results show that the dynamical adaptation of the delays law to the geometry of the piece leads to very good performances

Exfoliation syndrome: assembling the puzzle pieces.

Science.gov (United States)

Pasquale, Louis R; Borrás, Terete; Fingert, John H; Wiggs, Janey L; Ritch, Robert

2016-09-01

To summarize various topics and the cutting edge approaches to refine XFS pathogenesis that were discussed at the 21st annual Glaucoma Foundation Think Tank meeting in New York City, Sept. 19-20, 2014. The highlights of three categories of talks on cutting edge research in the field were summarized. Exfoliation syndrome (XFS) is a systemic disorder with a substantial ocular burden, including high rates of cataract, cataract surgery complications, glaucoma and retinal vein occlusion. New information about XFS is akin to puzzle pieces that do not quite join together to reveal a clear picture regarding how exfoliation material (XFM) forms. Meeting participants concluded that it is unclear how the mild homocysteinemia seen in XFS might contribute to the disarrayed extracellular aggregates characteristic of this syndrome. Lysyl oxidase-like 1 (LOXL1) variants are unequivocally genetic risk factors for XFS but exactly how these variants contribute to the assembly of exfoliation material (XFM) remains unclear. Variants in a new genomic region, CACNA1A associated with XFS, may alter calcium concentrations at the cell surface and facilitate XFM formation but much more work is needed before we can place this new finding in proper context. It is hoped that various animal model and ex vivo systems will emerge that will allow for proper assembly of the puzzle pieces into a coherent picture of XFS pathogenesis. A clear understanding of XFS pathogenesis may lead to 'upstream solutions' to reduce the ocular morbidity produced by XFS. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Classification of delocalization power of global unitary operations in terms of LOCC one-piece relocalization

Directory of Open Access Journals (Sweden)

Akihito Soeda

2010-06-01

Full Text Available We study how two pieces of localized quantum information can be delocalized across a composite Hilbert space when a global unitary operation is applied. We classify the delocalization power of global unitary operations on quantum information by investigating the possibility of relocalizing one piece of the quantum information without using any global quantum resource. We show that one-piece relocalization is possible if and only if the global unitary operation is local unitary equivalent of a controlled-unitary operation. The delocalization power turns out to reveal different aspect of the non-local properties of global unitary operations characterized by their entangling power.

A comparative study of two-piece ostomy appliances.

Science.gov (United States)

Welser, Marion; Riedlinger, Inge; Prause, Ulla

The quality of life of people with a stoma may be affected by peristomal skin disorders and by frequent unplanned changes of ostomy appliances due to problems with those appliances. The aim of this study was to evaluate two new, two-piece ostomy appliances with mechanical couplings (both from the SenSura range by Coloplast) and their ability to address areas that may be important to the quality of life of people with stomas, including appliance changes, stool seepage and overfilling. The study design featured two comparative, crossover, randomized multi-centre studies that were conducted in Germany. The SenSura appliances were evaluated against established reference appliances. Seventy-three individuals with a colostomy (closed-end appliances) and 75 individuals with an ileostomy (drainable appliances) participated in the studies. The participants tested 4-6 flanges of each type within a maximum period of two weeks. The results demonstrated that there was less seepage of stool observed under the SenSura flange when it was removed (pappliances. The SenSura flanges had better adhesion and flexibility and were easier to remove than the references (pappliances on quality of life indicators - there were fewer unplanned changes and less seepage of stool was observed in patients using the SenSura products.

Mechanical control of mitotic progression in single animal cells

OpenAIRE

Cattin, Cedric J.; Düggelin, Marcel; Martinez-Martin, David; Gerber, Christoph; Müller, Daniel J.; Stewart, Martin P.

2015-01-01

Despite the importance of mitotic cell rounding in tissue development and cell proliferation, there remains a paucity of approaches to investigate the mechanical robustness of cell rounding. Here we introduce ion beam-sculpted microcantilevers that enable precise force-feedback-controlled confinement of single cells while characterizing their progression through mitosis. We identify three force regimes according to the cell response: small forces (∼5 nN) that accelerate mitotic progression, i...

Autoinflation Leading to Failure of Two-Piece Ambicor Implantable Penile Prosthesis: An Outcome from a Methodical Treatment of Recalcitrant Stuttering Priapism

Directory of Open Access Journals (Sweden)

R. Charles Welliver

2014-01-01

Full Text Available Introduction. We present the case of a patient who received a two-piece Ambicor penile prosthesis for idiopathic recurrent “stuttering” priapism refractory to other treatment options. The patient returned unable to deflate the device due to an interesting anatomically induced mechanical failure. Aims. To describe the method and findings of this inflatable prosthesis failure. Results. Prosthesis failure occurred due to restrictive corporal diameter and the unique characteristics of fluid reservoir location in the two-piece inflatable prosthesis. The patient was successfully converted to a semirigid prosthesis with resolution of the pain that was due to his prosthesis autoinflation. Conclusion. Stuttering priapism remains a challenging clinical problem. Penile implantation is a reasonable long-term solution in a patient refractory to less invasive options. In patients with fibrotic corpora, a malleable device should be considered (at least temporarily if unable to dilate comfortably to 13 mm.

Diffraction and interference of single de Broglie-wavelets. Deterministic wave mechanics

International Nuclear Information System (INIS)

Barut, A.O.

1993-05-01

Wavelets are localized nonspreading solutions of massless wave equations which move like massive quantum particles. They form a bridge between classical mechanics of point particles and wave functions of probabilistic quantum mechanics, both of which can be obtained by limiting processes. Here we develop a theory of the propagation of wavelets in the presence of boundaries and derive interference phenomena of quantum theory from the behavior of single events with ''hidden parameters''. (author). 8 refs, 1 fig

What if the hand piece spring disassembles during robotic radical prostatectomy?

Science.gov (United States)

Akbulut, Ziya; Canda, Abdullah Erdem; Atmaca, Ali Fuat; Asil, Erem; Isgoren, Egemen; Balbay, Mevlana Derya

2011-01-01

Robot-assisted laparoscopic radical prostatectomy (RALRP) is successfully being performed for treating prostate cancer (PCa). However, instrumentation failure associated with robotic procedures represents a unique new problem. We report the successful completion of RALRP in spite of a disassembled hand piece spring during the procedure. A PubMed/Medline search was made concerning robotic malfunction and robot-assisted laparoscopic radical prostatectomy to discuss our experience. We performed RALRP in a 60-year-old male patient with localized PCa. During the procedure, the spring of the hand piece disassembled, and we were not able to reassemble it. We completed the procedure successfully however without fixing the disassembled hand piece spring. We were able to grasp tissue and needles when we brought our fingers together. The only movement we needed to do was to move fingers apart to release tissue or needles caught by robotic instrument. Although malfunction risk related to the da Vinci Surgical System seems to be very low, it might still occur. Sometimes, simple maneuvers may compensate for the failed function as occurred in our case. However, patients should be informed before the operation about the possibility of converting their procedure to laparoscopic or open due to robotic malfunction.

A monolithic glass chip for active single-cell sorting based on mechanical phenotyping.

Science.gov (United States)

Faigle, Christoph; Lautenschläger, Franziska; Whyte, Graeme; Homewood, Philip; Martín-Badosa, Estela; Guck, Jochen

2015-03-07

The mechanical properties of biological cells have long been considered as inherent markers of biological function and disease. However, the screening and active sorting of heterogeneous populations based on serial single-cell mechanical measurements has not been demonstrated. Here we present a novel monolithic glass chip for combined fluorescence detection and mechanical phenotyping using an optical stretcher. A new design and manufacturing process, involving the bonding of two asymmetrically etched glass plates, combines exact optical fiber alignment, low laser damage threshold and high imaging quality with the possibility of several microfluidic inlet and outlet channels. We show the utility of such a custom-built optical stretcher glass chip by measuring and sorting single cells in a heterogeneous population based on their different mechanical properties and verify sorting accuracy by simultaneous fluorescence detection. This offers new possibilities of exact characterization and sorting of small populations based on rheological properties for biological and biomedical applications.

Imaging Action Potential in Single Mammalian Neurons by Tracking the Accompanying Sub-Nanometer Mechanical Motion.

Science.gov (United States)

Yang, Yunze; Liu, Xian-Wei; Wang, Hui; Yu, Hui; Guan, Yan; Wang, Shaopeng; Tao, Nongjian

2018-03-28

Action potentials in neurons have been studied traditionally by intracellular electrophysiological recordings and more recently by the fluorescence detection methods. Here we describe a label-free optical imaging method that can measure mechanical motion in single cells with a sub-nanometer detection limit. Using the method, we have observed sub-nanometer mechanical motion accompanying the action potential in single mammalian neurons by averaging the repeated action potential spikes. The shape and width of the transient displacement are similar to those of the electrically recorded action potential, but the amplitude varies from neuron to neuron, and from one region of a neuron to another, ranging from 0.2-0.4 nm. The work indicates that action potentials may be studied noninvasively in single mammalian neurons by label-free imaging of the accompanying sub-nanometer mechanical motion.

Quantum ground state and single-phonon control of a mechanical resonator.

Science.gov (United States)

O'Connell, A D; Hofheinz, M; Ansmann, M; Bialczak, Radoslaw C; Lenander, M; Lucero, Erik; Neeley, M; Sank, D; Wang, H; Weides, M; Wenner, J; Martinis, John M; Cleland, A N

2010-04-01

Quantum mechanics provides a highly accurate description of a wide variety of physical systems. However, a demonstration that quantum mechanics applies equally to macroscopic mechanical systems has been a long-standing challenge, hindered by the difficulty of cooling a mechanical mode to its quantum ground state. The temperatures required are typically far below those attainable with standard cryogenic methods, so significant effort has been devoted to developing alternative cooling techniques. Once in the ground state, quantum-limited measurements must then be demonstrated. Here, using conventional cryogenic refrigeration, we show that we can cool a mechanical mode to its quantum ground state by using a microwave-frequency mechanical oscillator-a 'quantum drum'-coupled to a quantum bit, which is used to measure the quantum state of the resonator. We further show that we can controllably create single quantum excitations (phonons) in the resonator, thus taking the first steps to complete quantum control of a mechanical system.

Ultrasonic non-destructive testing of pieces of complex geometry with a flexible phased array transducer

Science.gov (United States)

Chatillon; Cattiaux; Serre; Roy

2000-03-01

Ultrasonic non-destructive testing of components of complex geometry in the nuclear industry faces several difficulties: sensitivity variations due to unmatched contact, inaccurate localization of defects due to variations of transducer orientation, and uncovered area of the component. To improve the performances of such testing and defect characterization, we propose a new concept of ultrasonic contact phased array transducer. The phased array transducer has a flexible radiating surface able to fit the actual surface of the piece to optimize the contact and thus the sensitivity of the test. To control the transmitted field, and therefore to improve the defect characterization, a delay law optimizing algorithm is developed. To assess the capability of such a transducer, the Champ-Sons model, developed at the French Atomic Energy Commission for predicting field radiated by arbitrary transducers into pieces, has to be extended to sources directly in contact with pieces of complex geometry. The good behavior of this new type of probe predicted by computations is experimentally validated with a jointed transducer positioned on pieces of various profiles.

Pigment dispersion syndrome and pigmentary glaucoma after secondary sulcus transscleral fixation of single-piece foldable posterior chamber intraocular lenses in Chinese aphakic patients.

Science.gov (United States)

Tong, Nianting; Liu, Fuling; Zhang, Ting; Wang, Liangyu; Zhou, Zhanyu; Gong, Huimin; Yuan, Fuxiang

2017-05-01

To describe secondary pigment dispersion syndrome (PDS) and pigmentary glaucoma after secondary sulcus transscleral fixation of 1-piece hydrophobic acrylic foldable posterior chamber intraocular lenses (PC IOLs) in aphakic patients in a Chinese population. Department of Ophthalmology, Qingdao Municipal Hospital, Qingdao, China. Retrospective case series. This chart review included eyes that had secondary sulcus transscleral fixation of a 1-piece hydrophobic acrylic foldable PC IOL (Tecnis ZCB00) between March 2011 and March 2014. The patients' demographic data, clinical data, postoperative complications, intervals between initial surgery and the onset of PDS, pigmentary glaucoma occurrences, and findings on slitlamp biomicroscopy, gonioscopy, and ultrasound biomicroscopy (UBM) were recorded. The study comprised 23 consecutive eyes of 21 patients. Seventeen eyes of 16 patients were diagnosed with PDS, and 7 eyes of 6 patients were diagnosed with pigmentary glaucoma. The slitlamp examination and UBM showed that the location between the IOL optic and the posterior surface of the iris was very close. Slitlamp examination of the anterior chamber angle using a gonioscope showed dense pigment deposition on the IOL surfaces. A reverse pupillary block was found in 10 eyes of 9 patients. Other postoperative complications included intraocular hemorrhage, pupillary capture of the IOL optic, IOL tilt, IOL decentration, IOL dislocation, and suture erosion. The 1-piece hydrophobic acrylic foldable PC IOL was not suitable for sulcus transscleral fixation because of a high incidence of PDS and pigmentary glaucoma after surgery in a Chinese population. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Mechanical properties of intra-ocular lenses

Science.gov (United States)

Ehrmann, Klaus; Kim, Eon; Parel, Jean-Marie

2008-02-01

Cataract surgery usually involves the replacement of the natural crystalline lens with a rigid or foldable intraocular lens to restore clear vision for the patient. While great efforts have been placed on optimising the shape and optical characteristics of IOLs, little is know about the mechanical properties of these devices and how they interact with the capsular bag once implanted. Mechanical properties measurements were performed on 8 of the most commonly implanted IOLs using a custom build micro tensometer. Measurement data will be presented for the stiffness of the haptic elements, the buckling resistance of foldable IOLs, the dynamic behaviour of the different lens materials and the axial compressibility. The biggest difference between the lens types was found between one-piece and 3-piece lenses with respect to the flexibility of the haptic elements

Final report on the UKAEA defect detection trials on test pieces 3 and 4. December 1982

International Nuclear Information System (INIS)

Lock, D.L.; Cowburn, K.J.

1983-03-01

The report follows ND-R-845(R) which described the scope, inspection procedures and results of the defect detection trials on test pieces 3 and 4. The work has been aimed at assessing the ability of non-destructive testing techniques, to detect and size defects near the clad/base metal interface of a flat piece and the inner radius of a PWR inlet nozzle. Following the destructive examination of the test pieces at Ispra, the true sizes of the intended defects are now known. These sizes are compared with that intended and the performance of the inspection teams reviewed. (author)

Mass sensors with mechanical traps for weighing single cells in different fluids.

Science.gov (United States)

Weng, Yaochung; Delgado, Francisco Feijó; Son, Sungmin; Burg, Thomas P; Wasserman, Steven C; Manalis, Scott R

2011-12-21

We present two methods by which single cells can be mechanically trapped and continuously monitored within the suspended microchannel resonator (SMR) mass sensor. Since the fluid surrounding the trapped cell can be quickly and completely replaced on demand, our methods are well suited for measuring changes in cell size and growth in response to drugs or other chemical stimuli. We validate our methods by measuring the density of single polystyrene beads and Saccharomyces cerevisiae yeast cells with a precision of approximately 10(-3) g cm(-3), and by monitoring the growth of single mouse lymphoblast cells before and after drug treatment.

Two-piece hollow bulb obturator

Directory of Open Access Journals (Sweden)

Subramaniam Elangovan

2011-01-01

Full Text Available There are various types of obturator fabrication achievable by prosthodontist. Maxillectomy, which is a term used by head and neck surgeons and prosthodontists to describe the partial or total removal of the maxilla in patients suffering from benign or malignant neoplasms is a defect for which to provide an effective obturator is a difficult task for the maxillofacial prosthodontist. Multidisciplinary treatment planning is essential to achieve adequate retention and function for the prosthesis. Speech is often unintelligible as a result of the marked defects in articulation and nasal resonance. This paper describes how to achieve the goal for esthetics and phonetics and also describes the fabrication of a hollow obturator by two piece method, which is simple and maybe used as definitive obturator for maximum comfort of the patient.

Comparison study on mechanical properties single step and three step artificial aging on duralium

Science.gov (United States)

Tsamroh, Dewi Izzatus; Puspitasari, Poppy; Andoko, Sasongko, M. Ilman N.; Yazirin, Cepi

2017-09-01

Duralium is kind of non-ferro alloy that used widely in industrial. That caused its properties such as mild, high ductility, and resistance from corrosion. This study aimed to know mechanical properties of duralium on single step and three step articial aging process. Mechanical properties that discussed in this study focused on toughness value, tensile strength, and microstructure of duralium. Toughness value of single step artificial aging was 0.082 joule/mm2, and toughness value of three step artificial aging was 0,0721 joule/mm2. Duralium tensile strength of single step artificial aging was 32.36 kgf/mm^2, and duralium tensile strength of three step artificial aging was 32,70 kgf/mm^2. Based on microstructure photo of duralium of single step artificial aging showed that precipitate (θ) was not spreading evenly indicated by black spot which increasing the toughness of material. While microstructure photo of duralium that treated by three step artificial aging showed that it had more precipitate (θ) spread evenly compared with duralium that treated by single step artificial aging.

Single and two-mode mechanical squeezing of an optically levitated nanodiamond via dressed-state coherence

International Nuclear Information System (INIS)

Ge, Wenchao; Bhattacharya, M

2016-01-01

Nonclassical states of macroscopic objects are promising for ultrasensitive metrology as well as testing quantum mechanics. In this work, we investigate dissipative mechanical quantum state engineering in an optically levitated nanodiamond. First, we study single-mode mechanical squeezed states by magnetically coupling the mechanical motion to a dressed three-level system provided by a nitrogen-vacancy center in the nanoparticle. Quantum coherence between the dressed levels is created via microwave fields to induce a two-phonon transition, which results in mechanical squeezing. Remarkably, we find that in ultrahigh vacuum quantum squeezing is achievable at room temperature with feedback cooling. For moderate vacuum, quantum squeezing is possible with cryogenic temperature. Second, we present a setup for two mechanical modes coupled to the dressed three levels, which results in two-mode squeezing analogous to the mechanism of the single-mode case. In contrast to previous works, our study provides a deterministic method for engineering macroscopic squeezed states without the requirement for a cavity. (paper)

Single and two-mode mechanical squeezing of an optically levitated nanodiamond via dressed-state coherence

Science.gov (United States)

Ge, Wenchao; Bhattacharya, M.

2016-10-01

Nonclassical states of macroscopic objects are promising for ultrasensitive metrology as well as testing quantum mechanics. In this work, we investigate dissipative mechanical quantum state engineering in an optically levitated nanodiamond. First, we study single-mode mechanical squeezed states by magnetically coupling the mechanical motion to a dressed three-level system provided by a nitrogen-vacancy center in the nanoparticle. Quantum coherence between the dressed levels is created via microwave fields to induce a two-phonon transition, which results in mechanical squeezing. Remarkably, we find that in ultrahigh vacuum quantum squeezing is achievable at room temperature with feedback cooling. For moderate vacuum, quantum squeezing is possible with cryogenic temperature. Second, we present a setup for two mechanical modes coupled to the dressed three levels, which results in two-mode squeezing analogous to the mechanism of the single-mode case. In contrast to previous works, our study provides a deterministic method for engineering macroscopic squeezed states without the requirement for a cavity.

Composing Interactive Dance Pieces for the MotionComposer, a device for Persons with Disabilities

OpenAIRE

Bergsland, Andreas; Wechsler, Robert

2015-01-01

The authors have developed a new hardware/software device for persons with disabilities (the MotionComposer), and in the process created a number of interactive dance pieces for non- disabled professional dancers. The paper briefly describes the hardware and motion tracking software of the device before going into more detail concerning the mapping strategies and sound design applied to three interactive dance pieces. The paper concludes by discussing a particular philosophy championing trans...

The Key Pieces of the Career Survival and Success Puzzle.

Science.gov (United States)

Simonetti, Jack L.

1999-01-01

Analysis of career-success factors identified by 5,000 managers yielded 10 key pieces: excellent performance record, communication skills, interpersonal skills, personality, skill currency, significant work experiences, power, ability to withstand pressure, ability to make difficult decisions, and having a mentor. (SK)

A Novel Computer-Aided Design/Computer-Assisted Manufacture Method for One-Piece Removable Partial Denture and Evaluation of Fit.

Science.gov (United States)

Ye, Hongqiang; Li, Xinxin; Wang, Guanbo; Kang, Jing; Liu, Yushu; Sun, Yuchun; Zhou, Yongsheng

2018-02-15

To investigate a computer-aided design/computer-aided manufacturing (CAD/CAM) process for producing one-piece removable partial dentures (RPDs) and to evaluate their fits in vitro. A total of 15 one-piece RPDs were designed using dental CAD and reverse engineering software and then fabricated with polyetheretherketone (PEEK) using CAM. The gaps between RPDs and casts were measured and compared with traditional cast framework RPDs. Gaps were lower for one-piece PEEK RPDs compared to traditional RPDs. One-piece RPDs can be manufactured by CAD/CAM, and their fits were better than those of traditional RPDs.

Low temperature deformation mechanisms in LiF single crystals

International Nuclear Information System (INIS)

Fotedar, H.L.; Stroebe, T.G.

1976-01-01

An analysis of the deformation behavior of high purity LiF single crystals is given using yielding and work hardening data and thermally activated deformation parameters obtained in the temperature range 77-423 0 K. It is found that while the Fleischer mechanism is apparently valid experimentally over the thermally activated temperature range, vacancies produced in large numbers at 77 0 K could also play a role in determining the critical resolved shear stress at that temperature

Mechanical analysis of single myocyte contraction in a 3-D elastic matrix.

Directory of Open Access Journals (Sweden)

John Shaw

Full Text Available Cardiac myocytes experience mechanical stress during each heartbeat. Excessive mechanical stresses under pathological conditions cause functional and structural remodeling that lead to heart diseases, yet the precise mechanisms are still incompletely understood. To study the cellular and molecular level mechanotransduction mechanisms, we developed a new 'cell-in-gel' experimental system to exert multiaxial (3-D stresses on a single myocyte during active contraction.Isolated myocytes are embedded in an elastic hydrogel to simulate the mechanical environment in myocardium (afterload. When electrically stimulated, the in-gel myocyte contracts while the matrix resists shortening and broadening of the cell, exerting normal and shear stresses on the cell. Here we provide a mechanical analysis, based on the Eshelby inclusion problem, of the 3-D strain and stress inside and outside the single myocyte during contraction in an elastic matrix.(1 The fractional shortening of the myocyte depends on the cell's geometric dimensions and the relative stiffness of the cell to the gel. A slender or softer cell has less fractional shortening. A myocyte of typical dimensions embedded in a gel of similar elastic stiffness can contract only 20% of its load-free value. (2 The longitudinal stress inside the cell is about 15 times the transverse stress level. (3 The traction on the cell surface is highly non-uniform, with a maximum near its ends, showing 'hot spots' at the location of intercalated disks. (4 The mechanical energy expenditure of the myocyte increases with the matrix stiffness in a monotonic and nonlinear manner.Our mechanical analyses provide analytic solutions that readily lend themselves to parametric studies. The resulting 3-D mapping of the strain and stress states serve to analyze and interpret ongoing cell-in-gel experiments, and the mathematical model provides an essential tool to decipher and quantify mechanotransduction mechanisms in cardiac

Wear mechanisms of coated hardmetals

International Nuclear Information System (INIS)

Richter, V.

2001-01-01

In the paper several aspects of the wear mechanisms of coated hardmetals, ceramics and super-hard materials (CBN) in machining cast iron are discussed, with particular attention being given to high-speed machining of different cast iron grades. The influence of machining parameters, microstructure, composition and mechanical and chemical properties of the cutting tool and the work-piece material on wear are considered. (author)

Quantum and classical control of single photon states via a mechanical resonator

International Nuclear Information System (INIS)

Basiri-Esfahani, Sahar; Myers, Casey R; Combes, Joshua; Milburn, G J

2016-01-01

Optomechanical systems typically use light to control the quantum state of a mechanical resonator. In this paper, we propose a scheme for controlling the quantum state of light using the mechanical degree of freedom as a controlled beam splitter. Preparing the mechanical resonator in non-classical states enables an optomechanical Stern–Gerlach interferometer. When the mechanical resonator has a small coherent amplitude it acts as a quantum control, entangling the optical and mechanical degrees of freedom. As the coherent amplitude of the resonator increases, we recover single photon and two-photon interference via a classically controlled beam splitter. The visibility of the two-photon interference is particularly sensitive to coherent excitations in the mechanical resonator and this could form the basis of an optically transduced weak-force sensor. (paper)

Electrical properties and mechanical stability of anchoring groups for single-molecule electronics

Directory of Open Access Journals (Sweden)

Riccardo Frisenda

2015-07-01

Full Text Available We report on an experimental investigation of transport through single molecules, trapped between two gold nano-electrodes fabricated with the mechanically controlled break junction (MCBJ technique. The four molecules studied share the same core structure, namely oligo(phenylene ethynylene (OPE3, while having different aurophilic anchoring groups: thiol (SAc, methyl sulfide (SMe, pyridyl (Py and amine (NH2. The focus of this paper is on the combined characterization of the electrical and mechanical properties determined by the anchoring groups. From conductance histograms we find that thiol anchored molecules provide the highest conductance; a single-level model fit to current–voltage characteristics suggests that SAc groups exhibit a higher electronic coupling to the electrodes, together with better level alignment than the other three groups. An analysis of the mechanical stability, recording the lifetime in a self-breaking method, shows that Py and SAc yield the most stable junctions while SMe form short-lived junctions. Density functional theory combined with non-equlibrium Green’s function calculations help in elucidating the experimental findings.

MECHANICAL CHARACTERISTICS OF THREE-PHASE INDUCTION MOTORS WITH SINGLE-PHASE POWER SUPPLY

Directory of Open Access Journals (Sweden)

V.S. Malyar

2016-06-01

Full Text Available Aim. Development of a method for calculating mechanical characteristics of three-phase induction motors with single-phase power supply. Methods. The developed algorithm is based on the high-adequacy mathematical model of motor and projection method for solving the boundary problem for equations of electrical circuits balance presented in the three-phase coordinate system. As a result of asymmetry of power supply to the stator windings, in steady state, flux-linkage and current change according to the periodic law. They are determined by solving the boundary problem. Results. The developed mathematical model allows determining periodic dependence of coordinates as a function of slip and, based on them, mechanical characteristics of motors. Academic novelty. The developed method relies on a completely new mathematical approach to calculation of stationary modes of nonlinear electromagnetic circuits, which allows obtaining periodic solution in a timeless domain. Practical value. Using the developed calculation algorithm, one can select capacitance required to start an induction motor with single-phase power supply and calculate static mechanical characteristics at a given capacitance.

Biased Brownian motion mechanism for processivity and directionality of single-headed myosin-VI.

Science.gov (United States)

Iwaki, Mitsuhiro; Iwane, Atsuko Hikikoshi; Ikebe, Mitsuo; Yanagida, Toshio

2008-01-01

Conventional form to function as a vesicle transporter is not a 'single molecule' but a coordinated 'two molecules'. The coordinated two molecules make it complicated to reveal its mechanism. To overcome the difficulty, we adopted a single-headed myosin-VI as a model protein. Myosin-VI is an intracellular vesicle and organelle transporter that moves along actin filaments in a direction opposite to most other known myosin classes. The myosin-VI was expected to form a dimer to move processively along actin filaments with a hand-over-hand mechanism like other myosin organelle transporters. However, wild-type myosin-VI was demonstrated to be monomer and single-headed, casting doubt on its processivity. Using single molecule techniques, we show that green fluorescent protein (GFP)-fused single-headed myosin-VI does not move processively. However, when coupled to a 200 nm polystyrene bead (comparable to an intracellular vesicle in size) at a ratio of one head per bead, single-headed myosin-VI moves processively with large (40 nm) steps. Furthermore, we found that a single-headed myosin-VI-bead complex moved more processively in a high-viscous solution (40-fold higher than water) similar to cellular environment. Because diffusion of the bead is 60-fold slower than myosin-VI heads alone in water, we propose a model in which the bead acts as a diffusional anchor for the myosin-VI, enhancing the head's rebinding following detachment and supporting processive movement of the bead-monomer complex. This investigation will help us understand how molecular motors utilize Brownian motion in cells.

Application of gamma radiation to the nodes detection in Pinus Radiata (D.Don) wood pieces

International Nuclear Information System (INIS)

Morales, J.R.; Dinator, Maria I; Karsulovic C, Jose T.; Leon G, Adolfo

1996-01-01

Attenuation of 59.5 KeV photons provided by an Am-241 source, has been used to detect knots in lumber pieces from Pinus Radiata (D.Don). It is shown that the linear attenuation coefficient is a sensitive parameter to detect singularities in the structure of this material. The scanning of the piece provides profiles which define the position and extension of the singularity. (author)

[Preliminary study on standardization of production and processing of Angelicae Sinensis Radix pieces].

Science.gov (United States)

Nie, Rui-Jie; Wang, Ying-Zi; Sun, Zhen-Yang; Wang, Si-Yu; Zhang, Jing-Zhen

2017-12-01

Study on the standardization of Chinese materia medica is an important action for modernization and globalization for traditional Chinese medicine. Standardization on the processing of Chinese herbal pieces is an important part in the study on standardization of Chinese materia medica, so it is of great significance to establish the technical processing standards of Angelicae Sinensis Radix pieces for improving its quality. In this study, single factor experiment was designed to optimize the softening, cutting and drying processes of Angelicae Sinensis Radix. With ferulic acid, Angelicae Sinensis Radix polysaccharide, volatile oil and extracts (water and ethanol) content as the quality index, the effects of different softening, cutting and drying processes on the contents of the five components in Angelicae Sinensis Radix were analyzed, and the normalized distance evaluation method was used to analyze the experimental data. The results showed that the content of five components in Angelicae Sinensis Radix was affected by different softening methods and drying temperature, but the thickness of slice had little effect on the content. The best preparation process for Angelicae Sinensis Radix was as follows: Non-medicinal parts were removed; mildewed and rot as well as moth-eaten parts were removed; washed by the flowing drinking water; stacked in the drug pool; moistening method was used for softening, where 125 mL water was sprayed for every 1 kg of herbs every 2.5 h; upper part of herbs covered with clean and moist cotton, and cut into thin slices (1-2 mm) after 15 h moistening until appropriate softness, with disk thickness of 1-2 cm, then received blast drying for 6 h at 55 ℃, and turned over for 2 times during the drying. Copyright© by the Chinese Pharmaceutical Association.

Fabrication of single phase 2D homologous perovskite microplates by mechanical exfoliation

Science.gov (United States)

Li, Junze; Wang, Jun; Zhang, Yingjun; Wang, Haizhen; Lin, Gaoming; Xiong, Xuan; Zhou, Weihang; Luo, Hongmei; Li, Dehui

2018-04-01

The two-dimensional (2D) Ruddlesden-Popper type perovskites have attracted intensive interest for their great environmental stability and various potential optoelectronic applications. Fundamental understanding of the photophysical and electronic properties of the 2D perovskites with pure single phase is essential for improving the performance of the optoelectronic devices and designing devices with new architectures. Investigating the optical and electronic properties of these materials with pure single phase is required to obtain pure single phase 2D perovskites. Here, we report on an alternative approach to fabricate (C4H9NH3)2(CH3NH3) n-1Pb n I3n+1 microplates with pure single n-number perovskite phase for n  >  2 by mechanical exfoliation. Micro-photoluminescence and absorption spectroscopy studies reveal that the as-synthesized 2D perovskite plates for n  >  2 are comprised by dominant n-number phase and small inclusions of hybrid perovskite phases with different n values, which is supported by excitation power dependent photoluminescence. By mechanical exfoliation method, 2D perovskite microplates with the thickness of around 20 nm are obtained, which surprisingly have single n-number perovskite phase for n  =  2-5. In addition, we have demonstrated that the exfoliated 2D perovskite microplates can be integrated with other 2D layered materials such as boron nitride, and are able to be transferred to prefabricated electrodes for photodetections. Our studies not only provide a strategy to prepare 2D perovskites with a single n-number perovskite phase allowing us to extract the basic optical and electronic parameters of pure phase perovskites, but also demonstrate the possibility to integrate the 2D perovskites with other 2D layered materials to extend the device’s functionalities.

Evaluation of single crystal coefficients from mechanical and x-ray elastic constants of the polycrystal

International Nuclear Information System (INIS)

Hauk, V.; Kockelmann, H.

1979-01-01

Methods of calculation are developed for determination of single crystal elastic compliance or stiffness constants of cubic and hexagonal materials from mechanical and X-ray elastic constants of polycrystals. The calculations are applied to pure, cubic iron and hexagonal WC. There are no single crystal constants in the literature for WC, because no single crystals suitable for measurement are available. (orig.) [de

In vitro synchrotron-based radiography of micro-gap formation at the implant-abutment interface of two-piece dental implants.

Science.gov (United States)

Rack, A; Rack, T; Stiller, M; Riesemeier, H; Zabler, S; Nelson, K

2010-03-01

Micro-gap formation at the implant-abutment interface of two-piece dental implants was investigated in vitro using high-resolution radiography in combination with hard X-ray synchrotron radiation. Images were taken with the specimen under different mechanical loads of up to 100 N. The aim of this investigation was to prove the existence of micro-gaps for implants with conical connections as well as to study the mechanical behavior of the mating zone of conical implants during loading. Synchrotron-based radiography in comparison with classical laboratory radiography yields high spatial resolution in combination with high contrast even when exploiting micro-sized features in highly attenuating objects. The first illustration of a micro-gap which was previously indistinguishable by laboratory methods underlines that the complex micro-mechanical behavior of implants requires further in vitro investigations where synchrotron-based micro-imaging is one of the prerequisites.

DNA-cisplatin binding mechanism peculiarities studied with single molecule stretching experiments

Science.gov (United States)

Crisafuli, F. A. P.; Cesconetto, E. C.; Ramos, E. B.; Rocha, M. S.

2012-02-01

We propose a method to determine the DNA-cisplatin binding mechanism peculiarities by monitoring the mechanical properties of these complexes. To accomplish this task, we have performed single molecule stretching experiments by using optical tweezers, from which the persistence and contour lengths of the complexes can be promptly measured. The persistence length of the complexes as a function of the drug total concentration in the sample was used to deduce the binding data, from which we show that cisplatin binds cooperatively to the DNA molecule, a point which so far has not been stressed in binding equilibrium studies of this ligand.

Mechanisms of temporal variation in single-nephron blood flow in rats

DEFF Research Database (Denmark)

Yip, K P; Holstein-Rathlou, N H; Marsh, D J

1993-01-01

Modified laser-Doppler velocimetry was used to determine the number of different mechanisms regulating single-nephron blood flow. Two oscillations were identified in star vessel blood flow, one at 20-50 mHz and another at 100-200 mHz. Tubuloglomerular feedback (TGF) mediates the slower oscillation......, and the faster one is probably myogenic in origin. Acute hypertension increased autospectral power in the 20-50 mHz and 100-200 mHz frequency bands to 282 +/- 50 and 248 +/- 64%, respectively, of control even though mean single-nephron blood flow was autoregulated. Mean blood flow increased 24.6 +/- 6.1% when...... components in efferent arteriole blood flow....

Rhenium Mechanical Properties and Joining Technology

Science.gov (United States)

Reed, Brian D.; Biaglow, James A.

1996-01-01

Iridium-coated rhenium (Ir/Re) provides thermal margin for high performance and long life radiation cooled rockets. Two issues that have arisen in the development of flight Ir/Re engines are the sparsity of rhenium (Re) mechanical property data (particularly at high temperatures) required for engineering design, and the inability to directly electron beam weld Re chambers to C103 nozzle skirts. To address these issues, a Re mechanical property database is being established and techniques for creating Re/C103 transition joints are being investigated. This paper discusses the tensile testing results of powder metallurgy Re samples at temperatures from 1370 to 2090 C. Also discussed is the evaluation of Re/C103 transition pieces joined by both, explosive and diffusion bonding. Finally, the evaluation of full size Re transition pieces, joined by inertia welding, as well as explosive and diffusion bonding, is detailed.

Quantum Sensing of Mechanical Motion with a Single InAs Quantum Dot

Science.gov (United States)

2017-03-01

Wenner, J. M. Martinis, and A. N. Cleland, “ Quantum ground state and single- phonon control of a mechanical resonator.,” Nature, vol. 464, no...G. Nogues, S. Seidelin, J. Poizat, O. Arcizet, and M. Richard, “Strain-mediated coupling in a quantum dot- mechanical oscillator hybrid system...Pos 4 Dep 5 School of N upling quantu ctive for funda dded a semico nical resonat vances in thi es large ch ell as the spin for quantum s antum Dots

A new piece of the puzzle

CERN Multimedia

2005-01-01

The team responsible for the installation of the hadronic calorimeter's central barrel after completion of the assembly work. Assembly of the great ATLAS puzzle continues underground. On 10 December, the final module of the central barrel of the tile hadronic calorimeter was assembled. This piece of the tile calorimeter had already been assembled above ground during a "dress rehearsal" in 2003 (see Bulletin no 46/2003, 10 November 2003). The hadronic calorimeter's two other barrels, the so-called "extended barrels", remain to be assembled with this first central barrel, which now surrounds the electromagnetic calorimeter barrel that was lowered into the cavern at the end of October. At the end of November, the second of the eight barrel toroid coils was also installed.

Computational exploration of single-protein mechanics by steered molecular dynamics

Energy Technology Data Exchange (ETDEWEB)

Sotomayor, Marcos [Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio (United States)

2015-12-31

Hair cell mechanotransduction happens in tens of microseconds, involves forces of a few picoNewtons, and is mediated by nanometer-scale molecular conformational changes. As proteins involved in this process become identified and their high resolution structures become available, multiple tools are being used to explore their “single-molecule responses” to force. Optical tweezers and atomic force microscopy offer exquisite force and extension resolution, but cannot reach the high loading rates expected for high frequency auditory stimuli. Molecular dynamics (MD) simulations can reach these fast time scales, and also provide a unique view of the molecular events underlying protein mechanics, but its predictions must be experimentally verified. Thus a combination of simulations and experiments might be appropriate to study the molecular mechanics of hearing. Here I review the basics of MD simulations and the different methods used to apply force and study protein mechanics in silico. Simulations of tip link proteins are used to illustrate the advantages and limitations of this method.

Simulation of double-seaming in a two-piece aluminum can

International Nuclear Information System (INIS)

Romanko, Anne; Berry, Dale; Fox, David

2004-01-01

The aluminum can industry in the United States and Canada manufactures over 100 billion cans per year. Two-piece aluminum cans are commonly used to seal and deliver foodstuffs such as soft drinks, beer, pet food, and other perishable items. In order to ensure product safety and performance, the double seam between the can body and lid is a critical component of the package. Double-seaming is a method by which the flange of the can body and the curl of the end are folded over together such that the final joint is composed of five metal thicknesses. There are a number of design challenges involved with the art of double seaming, especially with the push to lightweight. Although the requirements vary by product, the typical beer package must be able to hold pressures in excess of 90psi. In addition, in production, double seaming is a high-speed operation with speeds as high as 3000 cans/minute on an 18-spindle seamer. For this high volume, low cost industry, understanding and optimizing the seaming process can advance the industry as well as help prevent various manufacturing problems that produce a poor seal between the two pieces of the can.To aid in understanding the mechanics of the can parts during double-seaming, a simulation procedure was developed and carried out on a 202 diameter beverage can and lid. Simulations were run with the explicit dynamics solver ABAQUS/Explicit using the continuum shell element technology available in the ABAQUS general purpose FEA program. The continuum shell is a shear-deformable shell element with the topology of an eight node brick. The element's formulation allows continuously varying, solution-dependent shell thickness and through-thickness pinching stress. One important advantage of using the continuum shell as opposed to a traditional shell element is that true contact interactions at the top and bottom surfaces of the can body and lid can be accurately modeled. With a conventional shell element, contact is performed at the

Simulation of Double-Seaming in a Two-piece Aluminum Can

Science.gov (United States)

Romanko, Anne; Berry, Dale; Fox, David

2004-06-01

The aluminum can industry in the United States and Canada manufactures over 100 billion cans per year. Two-piece aluminum cans are commonly used to seal and deliver foodstuffs such as soft drinks, beer, pet food, and other perishable items. In order to ensure product safety and performance, the double seam between the can body and lid is a critical component of the package. Double-seaming is a method by which the flange of the can body and the curl of the end are folded over together such that the final joint is composed of five metal thicknesses. There are a number of design challenges involved with the art of double seaming, especially with the push to lightweight. Although the requirements vary by product, the typical beer package must be able to hold pressures in excess of 90psi. In addition, in production, double seaming is a high-speed operation with speeds as high as 3000 cans/minute on an 18-spindle seamer. For this high volume, low cost industry, understanding and optimizing the seaming process can advance the industry as well as help prevent various manufacturing problems that produce a poor seal between the two pieces of the can. To aid in understanding the mechanics of the can parts during double-seaming, a simulation procedure was developed and carried out on a 202 diameter beverage can and lid. Simulations were run with the explicit dynamics solver ABAQUS/Explicit using the continuum shell element technology available in the ABAQUS general purpose FEA program. The continuum shell is a shear-deformable shell element with the topology of an eight node brick. The element's formulation allows continuously varying, solution-dependent shell thickness and through-thickness pinching stress. One important advantage of using the continuum shell as opposed to a traditional shell element is that true contact interactions at the top and bottom surfaces of the can body and lid can be accurately modeled. With a conventional shell element, contact is performed at the

The Work and Wages of Single Women, 1870-1920

OpenAIRE

Goldin, Claudia

1980-01-01

Single women dominated the U.S. female labor force from 1870 to 1920. Data on the home life and working conditions of single women in 1888 and 1907 enable the estimation of their earnings functions. Work in the manufacturing sector for these women was task-oriented and payment was frequently by the piece. Earnings rose steeply with experience and peaked early; learning was mainly on-the-job. Occupational segregation by sex was a partial product of the method of payment, and the early terminat...

Physics colloquium: Single-electron counting in quantum metrology and in statistical mechanics

CERN Multimedia

Geneva University

2011-01-01

GENEVA UNIVERSITY Ecole de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92olé   Lundi 17 octobre 2011 17h00 - Ecole de Physique, Auditoire Stueckelberg PHYSICS COLLOQUIUM « Single-electron counting in quantum metrology and in statistical mechanics » Prof. Jukka Pekola Low Temperature Laboratory, Aalto University Helsinki, Finland   First I discuss the basics of single-electron tunneling and its potential applications in metrology. My main focus is in developing an accurate source of single-electron current for the realization of the unit ampere. I discuss the principle and the present status of the so-called single- electron turnstile. Investigation of errors in transporting electrons one by one has revealed a wealth of observations on fundamental phenomena in mesoscopic superconductivity, including individual Andreev...

Computer Tool for Automatically Generated 3D Illustration in Real Time from Archaeological Scanned Pieces

OpenAIRE

Luis López; Germán Arroyo; Domingo Martín

2012-01-01

The graphical documentation process of archaeological pieces requires the active involvement of a professional artist to recreate beautiful illustrations using a wide variety of expressive techniques. Frequently, the artist’s work is limited by the inconvenience of working only with the photographs of the pieces he is going to illustrate. This paper presents a software tool that allows the easy generation of illustrations in real time from 3D scanned models. The developed interface allows the...

Well-Defined Cyclic Triblock Terpolymers: A Missing Piece of the Morphology Puzzle

KAUST Repository

Polymeropoulos, George; Bilalis, Panayiotis; Hadjichristidis, Nikolaos

2016-01-01

Two well-defined cyclic triblock terpolymers, missing pieces of the terpolymer morphology puzzle, consisting of poly(isoprene), polystyrene, and poly(2-vinylpyridine), were synthesized by combining the Glaser coupling reaction with anionic

Event-related brain responses while listening to entire pieces of music

DEFF Research Database (Denmark)

Poikonen, H; Alluri, V; Brattico, E

2016-01-01

ERPs in human elicited by continuous music. The ERPs were recorded during listening to a Tango Nuevo piece, a deep techno track and an acoustic lullaby. Acoustic features related to timbre, harmony, and dynamics of the audio signal were computationally extracted from the musical pieces. Negative...... deflation occurring around 100 milliseconds after the stimulus onset (N100) and positive deflation occurring around 200 milliseconds after the stimulus onset (P200) ERP responses to peak changes in the acoustic features were distinguishable and were often largest for Tango Nuevo. In addition to large...... changes in these musical features, long phases of low values that precede a rapid increase – and that we will call Preceding Low-Feature Phases – followed by a rapid increase enhanced the amplitudes of N100 and P200 responses. These ERP responses resembled those to simpler sounds, making it possible...

Material Composition of Bucket Foundation Transition Piece for Offshore Wind Turbines

DEFF Research Database (Denmark)

Nezhentseva, Anastasia; Andersen, Lars; Ibsen, Lars Bo

2010-01-01

In Denmark, production of renewable energy is focused on offshore wind turbines, since they make little if any inconvenience for residents in inhabited areas. High requirements are placed on the installation of the foundations which can cost about 30% of the total cost of the wind turbine....... This paper deals with the transition piece for a relatively novel type of foundation, the so-called suction bucket (caisson), focusing on the design of a transition piece connecting the turbine column with a suction bucket used as a monopod foundation for an offshore wind turbine. Since the current design...... practice is limited to the use of steel-flange-reinforced shear panels for the transition piece—a production that requires extensive welding work—a desirable solution is to find a material that provides lower cost and easier manufacturing without compromising the strength and stiffness. The paper compares...

The Hiroshima neutron dosimetry enigma: Missing puzzle piece No. 6

International Nuclear Information System (INIS)

Gold, Raymond

1999-01-01

More than a decade has elapsed since the serious nature of the discrepancy between neutron dosimetry experiments (E) and neutron transport calculations (C) for the Hiroshima site was identified. Since that time extensive efforts to resolve this Hiroshima neutron dosimetry enigma have not only failed, but now demonstrate that the magnitude of this discrepancy is much greater than initially estimated. The currently evaluated E/C ratio for thermal neutron fluence at the Hiroshima site increases rapidly with increasing slant range from the epicenter. In the slant range region beyond 1000 m, E/C exceeds unity by one to two orders of magnitude depending on the specific dosimetry data that are utilized. Principal features that characterize the Hiroshima neutron dosimetry enigma are summarized. Puzzle Piece No. 6: In-situ production and Prompt fallout of radionuclides from Little Boy is advanced as a possible contributory phenomenon to this enigma. (The atom bomb detonated over Hiroshima was called Little Boy.) Measurements of 60 Co and 152 Eu specific activity at the Hiroshima site are used to obtain order of magnitude numerical estimates that show this conjecture is plausible. Comparison of different 60 Co measurements at the Hiroshima site reveals that the variation of E/C with slant range depends on the method used to quantify 60 Co specific activity as well as the type of dosimetry samples that are employed. These 60 Co comparisons lend additional qualitative credence to this conjecture. Within the limits of presently available data, these assessments show that Puzzle Piece No. 6 qualitatively satisfies the principal features that characterize the Hiroshima neutron dosimetry enigma. Nevertheless, current lack of data prevent this conjecture from being conclusively confirmed or refuted. Consequently, specific recommendations are advanced to resolve the Hiroshima neutron dosimetry enigma with emphasis on experimental tests that can quantitatively evaluate Puzzle Piece

Comparison of the T-piece resuscitator with other neonatal manual ventilation devices: A qualitative review.

LENUS (Irish Health Repository)

2012-01-31

AIM: To review the literature surrounding various aspects of T-piece resuscitator use, with particular emphasis on the evidence comparing the device to other manual ventilation devices in neonatal resuscitation. DATA SOURCES: The Medline, EMBASE, Cochrane databases were searched in April 2011. Ongoing trials were identified using www.clinicaltrials.gov and www.controlled-trials.com. Additional studies from reference lists of eligible articles were considered. All studies including T-piece resuscitator use were eligible for inclusion. RESULTS: Thirty studies were included. There were two randomised controlled trials in newborn infants comparing the devices, one of which addressed short and intermediate term morbidity and mortality outcomes and found no difference between the T-piece resuscitator and self inflating bag. From manikin studies, advantages to the T-piece resuscitator include the delivery of inflating pressures closer to predetermined target pressures with least variation, the ability to provide prolonged inflation breaths and more consistent tidal volumes. Disadvantages include a technically more difficult setup, more time required to adjust pressures during resuscitation, a larger mask leak and less ability to detect changes in compliance. CONCLUSIONS: There is a need for appropriately designed randomised controlled trials in neonates to highlight the efficacy of one device over another. Until these are performed, healthcare providers should be appropriately trained in the use of the device available in their departments, and be aware of its own limitations.

Single-nary philosophy for non-linear study of mechanics of materials

International Nuclear Information System (INIS)

Tran, C.

2005-01-01

Non-linear study of mechanics of materials is formulated in this paper as a problem of meta-intelligent system analysis. Non-linearity will be singled out as an important concept for understanding of high-order complex systems. Through single-nary thinking, which will be represented in this work, we introduce a modification of Aristotelian philosophy using modal logic and multi-valued logic (these logics we call 'high-order' logic). Next, non-linear cause - effect relations are expressed through non-additive measures and multiple-information aggregation principles based on fuzzy integration. The study of real time behaviors, required experiences and intuition, will be realized using truth measures (non-additive measures) and a procedure for information processing in intelligence levels. (author)

Adaptive kanban control mechanism for a single-stage hybrid system

Science.gov (United States)

Korugan, Aybek; Gupta, Surendra M.

2002-02-01

In this paper, we consider a hybrid manufacturing system with two discrete production lines. Here the output of either production line can satisfy the demand for the same type of product without any penalties. The interarrival times for demand occurrences and service completions are exponentially distributed i.i.d. variables. In order to control this type of manufacturing system we suggest a single stage pull type control mechanism with adaptive kanbans and state independent routing of the production information.

Hybrid spin-nanomechanics with single spins in diamond mechanical oscillators

OpenAIRE

Barfuss, Arne

2017-01-01

Hybrid spin-oscillator systems, formed by single spins coupled to mechanical oscillators, have attracted ever-increasing attention over the past few years, triggered largely by the prospect of employing such devices as high-performance nanoscale sensors or transducers in multi-qubit networks. Provided the spin-oscillator coupling is strong and robust, such systems can even serve as test-beds for studying macroscopic objects in the quantum regime. In this thesis we present a novel hybrid sp...

The DS86 neutron dosimetry enigma: Some missing pieces to the puzzle

International Nuclear Information System (INIS)

Gold, R.

1994-01-01

International programs have been conducted over the last four decades to quantify the exposure of atom bomb survivors from Hiroshima and Nagasaki. Unfortunately, the quest for accurate gamma-ray and neutron exposure doses of atom bomb survivors has proven illusive. Efforts in the most recent of these programs, designated as Dosimetry System 1986 (DS86), have revealed a serious and persistent discrepancy between neutron transport calculations and thermal neutron activation measurements at the Hiroshima site, which will be called the DS86 neutron dosimetry enigma. It is established that this enigma is a complex puzzle that precludes simple solutions. This conclusion is deduced through the identification of a number of missing pieces to the puzzle. Implications and conclusions that can be inferred from these missing puzzle pieces are advanced

Relationships among the structural topology, bond strength, and mechanical properties of single-walled aluminosilicate nanotubes.

Science.gov (United States)

Liou, Kai-Hsin; Tsou, Nien-Ti; Kang, Dun-Yen

2015-10-21

Carbon nanotubes (CNTs) are regarded as small but strong due to their nanoscale microstructure and high mechanical strength (Young's modulus exceeds 1000 GPa). A longstanding question has been whether there exist other nanotube materials with mechanical properties as good as those of CNTs. In this study, we investigated the mechanical properties of single-walled aluminosilicate nanotubes (AlSiNTs) using a multiscale computational method and then conducted a comparison with single-walled carbon nanotubes (SWCNTs). By comparing the potential energy estimated from molecular and macroscopic material mechanics, we were able to model the chemical bonds as beam elements for the nanoscale continuum modeling. This method allowed for simulated mechanical tests (tensile, bending, and torsion) with minimum computational resources for deducing their Young's modulus and shear modulus. The proposed approach also enabled the creation of hypothetical nanotubes to elucidate the relative contributions of bond strength and nanotube structural topology to overall nanotube mechanical strength. Our results indicated that it is the structural topology rather than bond strength that dominates the mechanical properties of the nanotubes. Finally, we investigated the relationship between the structural topology and the mechanical properties by analyzing the von Mises stress distribution in the nanotubes. The proposed methodology proved effective in rationalizing differences in the mechanical properties of AlSiNTs and SWCNTs. Furthermore, this approach could be applied to the exploration of new high-strength nanotube materials.

Diagnosis of two textile pieces from Santarém Diocesan Museum: a multi-analytical approach

Directory of Open Access Journals (Sweden)

Rita Florentino Correia

2016-01-01

Full Text Available The present work aim was to study two composite textile pieces from Santarém Diocesan Museum, including their historic context, their conservation condition and the characterization of their constituent parts, which established the date of production. Both pieces belonged to the First Bishop of Daman (1840-1900 and were selected for their historic interest and originality, and for representing a case study in terms of materials, techniques and decoration. They are also a good example of the conservation problems that can occur in liturgical textiles. The diagnosis was extended using optical microscopy, Fourier transform infrared spectroscopy, energy dispersive X-ray fluorescence and Raman spectroscopy. These techniques allowed the identification of the fibres, binder, metals and pigments, confirming that the pieces date back to the late nineteenth century. Among the main forms of degradation, it was observed: structural deformations, dirt and material losses, not only in areas with fabric but also with metallic embroidery and painted layers.

The Ayre's T-piece turns 80: A 21st century review.

Science.gov (United States)

Oswald, Lauren; Smith, Emma-Jane; Mathew, Malcolm; Goonasekera, Chulananda

2018-06-07

Ayre's T-piece, first introduced 80 years ago, continues to be widely used in pediatric anesthesia despite colossal advances in equipment and technology. We present a review of its history, advantages, and disadvantages, and place in modern-day clinical practice. © 2018 John Wiley & Sons Ltd.

Developing an experimental case in aluminium foils 1100 to determine the maximum angle of formability in a piece by Dieless-SPIF process

Science.gov (United States)

Gabriel, Paramo; Adrian, Benitez

2014-07-01

Incremental sheet forming by the method of single point incremental forming Dieless-SPIF, is a widely studied process, experimented and developed in countries with high manufacturing technologies, with friendly costs when the productive configuration in a productivity system is based in small production batches. United states, United kingdom and France lead this type of studies and cases, developing various proof with experimental geometries, different from the national environment such as Colombia, Bolivia, Chile, Ecuador and Peru where this process where discretely studied. Previously mentioned, it pretends develop an experimental case of a particular geometry, identifying the maximum formability angle of material permissible for the forming of a piece in one pass, the analysis of forming limit curve (FLC), with the objective to emphasizes in this innovative method based in CAD-CAM technologies, compare with other analogous process of deformation sheet metal like embossing, take correct decisions about the viability and applicability of this process (Dieless) in a particular industrial piece, which responses to the necessities of productive configurations mentioned and be highly taken like a manufacturing alternative to the other conventional process of forming sheet metal like embossing, for systems with slow batches production.

Developing an experimental case in aluminium foils 1100 to determine the maximum angle of formability in a piece by Dieless-SPIF process

International Nuclear Information System (INIS)

Gabriel, Paramo; Adrian, Benitez

2014-01-01

Incremental sheet forming by the method of single point incremental forming Dieless-SPIF, is a widely studied process, experimented and developed in countries with high manufacturing technologies, with friendly costs when the productive configuration in a productivity system is based in small production batches. United states, United kingdom and France lead this type of studies and cases, developing various proof with experimental geometries, different from the national environment such as Colombia, Bolivia, Chile, Ecuador and Peru where this process where discretely studied. Previously mentioned, it pretends develop an experimental case of a particular geometry, identifying the maximum formability angle of material permissible for the forming of a piece in one pass, the analysis of forming limit curve (FLC), with the objective to emphasizes in this innovative method based in CAD-CAM technologies, compare with other analogous process of deformation sheet metal like embossing, take correct decisions about the viability and applicability of this process (Dieless) in a particular industrial piece, which responses to the necessities of productive configurations mentioned and be highly taken like a manufacturing alternative to the other conventional process of forming sheet metal like embossing, for systems with slow batches production

Mechanism Design for Single Leader Stackelberg Problems and Application to Procurement Auction Design

OpenAIRE

Garg, Dinesh; Narahari, Y

2008-01-01

In this paper, we focus on mechanism design for single leader Stackelberg problems, which are a special case of hierarchical decision making problems in which a distinguished agent, known as the leader, makes the first move and this action is followed by the actions of the remaining agents, which are known as the followers. These problems are also known as single leader rest follower (SLRF) problems. There are many examples of such problems in the areas of electronic commerce, supply chain ma...

Electrification: Connecting the Pieces in the Broader View

Energy Technology Data Exchange (ETDEWEB)

Gearhart, Chris C [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-11-28

Presented at the SELECT Annual Meeting on September 26, 2017, this PowerPoint presentation gives an overview of connectivity and automation and how these new technologies will impact society in both known and unknown ways. Electrification challenges and opportunities are also outlined as without electrification, connectivity and automation will just magnify the negative health, climate and economic problems of the current transportation systems. Electrification can provide benefits while mitigating the negative consequences. And with careful connection of all of the pieces from materials up through controls, a sustainable transportation eco-system is attainable.

Single molecule insights on conformational selection and induced fit mechanism

DEFF Research Database (Denmark)

Hatzakis, Nikos

2014-01-01

. To describe the molecular basis of this behavior, two main mechanisms have been advanced: 'induced fit' and 'conformational selection'. Our understanding of these models relies primarily on NMR, computational studies and kinetic measurements. These techniques report the average behavior of a large ensemble...... of unsynchronized molecules, often masking intrinsic dynamic behavior of proteins and biologically significant transient intermediates. Single molecule measurements are emerging as a powerful tool for characterizing protein function. They offer the direct observation and quantification of the activity, abundance...

Nilai Pendidikan Dalam Komik One Piece Jilid 1-23 Karya Eiichiro Oda (Sebuah Tinjauan Sosiologi Sastra)

OpenAIRE

Furqon, Muhammad Taufiq

2013-01-01

Furqon, Muhammad Taufiq. 2013. “Nilai Pendidikan dalam Komik One Piece Jilid 1-23 Karya Eiichiro Oda”. Skripsi S-1 Fakultas Ilmu Budaya Universitas Diponegoro Semarang. Permasalahan dalam penelitian ini adalah komik One Piece dilihat dari bentuknya hanya terdiri dari gambar dan teks, tetapi ada unsur-unsur fiksi terdapat di dalamnya seperti adanya tema, tokoh, latar,dan ada amanat yang ingin disampaikan pengarangnya. Sehingga pemahaman dan pemaknaan terhadapnya mampu memberikan manfaat bagi p...

Piecing It Together: The Effect of Background Music on Children's Puzzle Assembly.

Science.gov (United States)

Koolidge, Louis; Holmes, Robyn M

2018-04-01

This study explored the effects of background music on cognitive (puzzle assembly) task performance in young children. Participants were 87 primarily European-American children (38 boys, 49 girls; mean age = 4.77 years) enrolled in early childhood classes in the northeastern United States. Children were given one minute to complete a 12-piece puzzle task in one of three background music conditions: music with lyrics, music without lyrics, and no music. The music selection was "You're Welcome" from the Disney movie "Moana." Results revealed that children who heard the music without lyrics completed more puzzle pieces than children in either the music with lyrics or no music condition. Background music without distracting lyrics may be beneficial and superior to background music with lyrics for young children's cognitive performance even when they are engaged independently in a nonverbal task.

3D Thermal and Mechanical Analysis of a Single Event Burnout

Science.gov (United States)

Peretti, Gabriela; Demarco, Gustavo; Romero, Eduardo; Tais, Carlos

2015-08-01

This paper presents a study related to thermal and mechanical behavior of power DMOS transistors during a Single Event Burnout (SEB) process. We use a cylindrical heat generation region for emulating the thermal and mechanical phenomena related to the SEB. In this way, it is avoided the complexity of the mathematical treatment of the ion-device interaction. This work considers locating the heat generation region in positions that are more realistic than the ones used in previous work. For performing the study, we formulate and validate a new 3D model for the transistor that maintains the computational cost at reasonable level. The resulting mathematical models are solved by means of the Finite Element Method. The simulations results show that the failure dynamics is dominated by the mechanical stress in the metal layer. Additionally, the time to failure depends on the heat source position, for a given power and dimension of the generation region. The results suggest that 3D modeling should be considered for a detailed study of thermal and mechanical effects induced by SEBs.

Pigment dispersion and chronic intraocular pressure elevation after sulcus placement of 3-piece acrylic intraocular lens.

Science.gov (United States)

Almond, M Camille; Wu, Michael C; Chen, Philip P

2009-12-01

A 55-year-old man had phacoemulsification and implantation of a 3-piece acrylic intraocular lens (IOL) (AcrySof MA60AC) in the right eye. One month postoperatively, the intraocular pressure (IOP) was 48 mm Hg and peripheral transillumination defects were noted in the iris circumferentially, with the IOL optic edge visible as a silhouette. Gonioscopy showed dense pigmentation of the trabecular meshwork in the right eye, but in the left eye, only mild trabecular meshwork pigment was seen, along with a concave peripheral iris insertion. At 21 months, the right eye required 3 medications for IOP control. While pigment dispersion has been widely reported after placement of 1-piece acrylic IOLs in the ciliary sulcus, we conclude that in susceptible individuals with a concave peripheral iris insertion, pigment dispersion can occur with sulcus placement of a 3-piece acrylic model despite its thinner optic and angulated haptics.

Effect of pieces size of Empty Fruit Bunches (EFB) on composting of EFB mixed with activated liquid organic fertilizer

Science.gov (United States)

Trisakti, B.; Mhardela, P.; Husaini, T.; Irvan; Daimon, H.

2018-02-01

This research was to determine the effect of pieces sizes of oil palm empty fruit bunch (EFB) on the composting of EFB mixed with activated liquid organic fertilizer (ALOF) in a basket composter in order to obtain high quality compost. The composting process was started by cutting the EFB into pieces with varies sizes, inserting the EFB pieces into basket composter (33 cm W × 28 cm L × 40 cm H), and adding ALOF until moisture content (MC) in the range of 55-65%. During composting, the compost pile was turned every 3 days and the MC was maintained at 55-65% range by adding the ALOF. The sizes of the EFB pieces were varied into <1, 1-3, 4-7, 8-11, and 12-15 cm. The parameters analysed during the composting were temperature, pH, MC, compost weight, water holding capacity (WHC), CN ratio, and the quality of the final compost. Composting was carried out for 40 days and the best result obtained at EFB pieces size was 1-3 cm with compost characteristic were pH 9.0; MC 52.59%; WHC 76%; CN ratio 12.15; N 1.96%; P 0.58%; and K 0. 95%.

A mini-overview of single muscle fibre mechanics: the effects of age, inactivity and exercise in animals and humans.

Science.gov (United States)

Jee, Hyunseok; Kim, Jong-Hee

2017-09-05

Many basic movements of living organisms are dependent on muscle function. Muscle function allows for the coordination and harmonious integrity of movement that is necessary for various biological processes. Gross and fine motor skills are both regulated at the micro-level (single muscle fibre level), controlled by neuronal regulation, and it is therefore important to understand muscle function at both micro- and macro-levels to understand the overall movement of living organisms. Single muscle mechanics and the cellular environment of muscles fundamentally allow for the harmonious movement of our bodies. Indeed, a clear understanding of the functionality of muscle at the micro-level is indispensable for explaining muscular function at the macro-(whole gross muscle) level. By investigating single muscle fibre mechanics, we can also learn how other factors such Ca2+ kinetics, enzyme activity and contractile proteins can contribute to muscle mechanics at the micro- and macro-levels. Further, we can also describe how aging affects the capacity of skeletal muscle cells, as well as how exercise can prevent aging-based sarcopenia and frailty. The purpose of this review is to introduce and summarise the current knowledge of single muscle fibre mechanics in light of aging and inactivity. We then describe how exercise mitigates negative muscle adaptations that occur under those circumstances. In addition, single muscle fibre mechanics in both animal and human models are discussed.

Mechanical impedance of the sitting human body in single-axis compared to multi-axis whole-body vibration exposure.

Science.gov (United States)

Holmlund, P; Lundström, R

2001-01-01

The study was aimed to investigate the mechanical impedance of the sitting human body and to compare data obtained in laboratory single-axis investigations with multi-axis data from in vehicle measurements. The experiments were performed in a laboratory for single-axis measurements. The multi-axis exposure was generated with an eight-seat minibus where the rear seats had been replaced with a rigid one. The subjects in the multi-axis experiment all participated in the single-axis experiments. There are quite a few investigations in the literature describing the human response to single-axis exposure. The response from the human body can be expected to be affected by multi-axis input in a different way than from a single-axis exposure. The present knowledge of the effect of multiple axis exposure is very limited. The measurements were performed using a specially designed force and accelerometer plate. This plate was placed between the subject and the hard seat. Outcome shows a clear difference between mechanical impedance for multi-axis exposure compared to single-axis. This is especially clear in the x-direction where the difference is very large. The conclusion is that it seems unlikely that single-axis mechanical impedance data can be directly transferred to a multi-axis environment. This is due to the force cross-talk between different directions.

Computation of Hydration Free Energies Using the Multiple Environment Single System Quantum Mechanical/Molecular Mechanical Method.

Science.gov (United States)

König, Gerhard; Mei, Ye; Pickard, Frank C; Simmonett, Andrew C; Miller, Benjamin T; Herbert, John M; Woodcock, H Lee; Brooks, Bernard R; Shao, Yihan

2016-01-12

A recently developed MESS-E-QM/MM method (multiple-environment single-system quantum mechanical molecular/mechanical calculations with a Roothaan-step extrapolation) is applied to the computation of hydration free energies for the blind SAMPL4 test set and for 12 small molecules. First, free energy simulations are performed with a classical molecular mechanics force field using fixed-geometry solute molecules and explicit TIP3P solvent, and then the non-Boltzmann-Bennett method is employed to compute the QM/MM correction (QM/MM-NBB) to the molecular mechanical hydration free energies. For the SAMPL4 set, MESS-E-QM/MM-NBB corrections to the hydration free energy can be obtained 2 or 3 orders of magnitude faster than fully converged QM/MM-NBB corrections, and, on average, the hydration free energies predicted with MESS-E-QM/MM-NBB fall within 0.10-0.20 kcal/mol of full-converged QM/MM-NBB results. Out of five density functionals (BLYP, B3LYP, PBE0, M06-2X, and ωB97X-D), the BLYP functional is found to be most compatible with the TIP3P solvent model and yields the most accurate hydration free energies against experimental values for solute molecules included in this study.

Refractive index sensor based on an abrupt taper Michelson interferometer in a single-mode fiber.

Science.gov (United States)

Tian, Zhaobing; Yam, Scott S-H; Loock, Hans-Peter

2008-05-15

A simple refractive index sensor based on a Michelson interferometer in a single-mode fiber is constructed and demonstrated. The sensor consists of a single symmetrically abrupt taper region in a short piece of single-mode fiber that is terminated by approximately 500 nm thick gold coating. The sensitivity of the new sensor is similar to that of a long-period-grating-type sensor, and its ease of fabrication offers a low-cost alternative to current sensing applications.

Research of thermal dynamic characteristics for variable load single screw refrigeration compressor with different capacity control mechanism

International Nuclear Information System (INIS)

Wang, Zengli; Wang, Zhenbo; Wang, Jun; Jiang, Wenchun; Feng, Quanke

2017-01-01

Highlights: • Theoretical models of SSRC under part-load condition have been established. • The experiment of SSRC performance under part-load condition was conducted. • Thermal dynamic characteristic of SSRC under part-load condition was gained. • Economy and reliability of SSRC under part-load condition was analyzed. - Abstract: In the single screw refrigeration compressor (SSRC), the capacity control mechanism is normally employed to meet the actual required cooling capacity under different load conditions. In this paper, theoretical calculation models describing the working process of the SSRC with the single slide valve capacity control mechanism (SVCCM) and SSRC with the frequency conversion regulating mechanism (FCRM) are established to research the thermal dynamic characteristics for variable load SSRC under part-load conditions. Experimental investigation on a SSRC under part-load conditions is also carried out to verify the theoretical calculation models. By using these validated models, the thermodynamic performances and dynamic characteristics of the SSRC with different capacity control mechanism under part-load conditions have been analyzed and compared. Through the comparison, the economical efficiency and reliability of the SSRC with different capacity control mechanism were obtained. All of these works can provide the basis for the later optimization design for the variable load single screw refrigeration compressor.

Synchronization of impacting mechanical systems with a single constraint

Science.gov (United States)

Baumann, Michael; Biemond, J. J. Benjamin; Leine, Remco I.; van de Wouw, Nathan

2018-01-01

This paper addresses the synchronization problem of mechanical systems subjected to a single geometric unilateral constraint. The impacts of the individual systems, induced by the unilateral constraint, generally do not coincide even if the solutions are arbitrarily 'close' to each other. The mismatch in the impact time instants demands a careful choice of the distance function to allow for an intuitively correct comparison of the discontinuous solutions resulting from the impacts. We propose a distance function induced by the quotient metric, which is based on an equivalence relation using the impact map. The distance function obtained in this way is continuous in time when evaluated along jumping solutions. The property of maximal monotonicity, which is fulfilled by most commonly used impact laws, is used to significantly reduce the complexity of the distance function. Based on the simplified distance function, a Lyapunov function is constructed to investigate the synchronization problem for two identical one-dimensional mechanical systems. Sufficient conditions for the uncoupled individual systems are provided under which local synchronization is guaranteed. Furthermore, we present an interaction law which ensures global synchronization, also in the presence of grazing trajectories and accumulation points (Zeno behavior). The results are illustrated using numerical examples of a 1-DOF mechanical impact oscillator which serves as stepping stone in the direction of more general systems.

Leaching of metals from large pieces of printed circuit boards using citric acid and hydrogen peroxide.

Science.gov (United States)

Jadhav, Umesh; Su, C; Hocheng, Hong

2016-12-01

In the present study, the leaching of metals from large pieces of computer printed circuit boards (CPCBs) was studied. A combination of citric acid (0.5 M) and 1.76 M hydrogen peroxide (H 2 O 2 ) was used to leach the metals from CPCB piece. The influence of system variables such as H 2 O 2 concentration, concentration of citric acid, shaking speed, and temperature on the metal leaching process was investigated. The complete metal leaching was achieved in 4 h from a 4 × 4 cm CPCB piece. The presence of citric acid and H 2 O 2 together in the leaching solution is essential for complete metal leaching. The optimum addition amount of H 2 O 2 was 5.83 %. The citric acid concentration and shaking speed had an insignificant effect on the leaching of metals. The increase in the temperature above 30 °C showed a drastic effect on metal leaching process.

49 CFR 236.335 - Dogs, stops and trunnions of mechanical locking.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Dogs, stops and trunnions of mechanical locking..., AND APPLIANCES Interlocking Rules and Instructions § 236.335 Dogs, stops and trunnions of mechanical locking. Driving pieces, dogs, stops and trunnions shall be rigidly secured to locking bars. Swing dogs...

Archaeology of Chilean pre-hispanic pieces using induced x-ray fluorescence

Energy Technology Data Exchange (ETDEWEB)

Morales, J.R.; Dinator, M.I. [Universidad de Chile, Facultad de Ciencias, Santiago (Chile); Tellez, F. [Universidad Catolica del Norte, I.I.A. San Pedro de Atacama (Chile)

2001-09-01

Full text: One of the most famous archaeological sites of Chile is San Pedro de Atacama in the north Andean highlands. The site, 68.23 W, 22.89 S, is close to the border lines with Argentina and Bolivia and was occupied by different cultures in the past like Atacameos and lately by Incas in s. X V. About a century later Hispanic explorers visited the zone. The area is rich in tombs and remains. Due to the abundance of minerals, metallurgy was practiced by pre-Hispanic cultures. This work is part of a study concerning the characterization of metallic artifacts found in several excavations. The elemental composition can help in determining the provenance of the pieces, and the metallurgical techniques used. A set of twenty pieces including hatchets, knifes, chisels, maces and bells were analyzed by X ray fluorescence induced by photons of 59.5 keV provided by a source of Am-241. Detection of Mn, Fe, Ni, Cu, As, Zr, Ag, Sn, Sb, Ba, and Pb has allowed determination of their provenance. (Author)

Archaeology of Chilean pre-hispanic pieces using induced x-ray fluorescence

International Nuclear Information System (INIS)

Morales, J.R.; Dinator, M.I.; Tellez, F.

2001-01-01

Full text: One of the most famous archaeological sites of Chile is San Pedro de Atacama in the north Andean highlands. The site, 68.23 W, 22.89 S, is close to the border lines with Argentina and Bolivia and was occupied by different cultures in the past like Atacameos and lately by Incas in s. X V. About a century later Hispanic explorers visited the zone. The area is rich in tombs and remains. Due to the abundance of minerals, metallurgy was practiced by pre-Hispanic cultures. This work is part of a study concerning the characterization of metallic artifacts found in several excavations. The elemental composition can help in determining the provenance of the pieces, and the metallurgical techniques used. A set of twenty pieces including hatchets, knifes, chisels, maces and bells were analyzed by X ray fluorescence induced by photons of 59.5 keV provided by a source of Am-241. Detection of Mn, Fe, Ni, Cu, As, Zr, Ag, Sn, Sb, Ba, and Pb has allowed determination of their provenance. (Author)

Going nuts: Measuring free-fall acceleration by analyzing the sound of falling metal pieces

Science.gov (United States)

Kuhn, Jochen; Vogt, Patrik; Theilmann, Florian

2016-03-01

Galilei presented the kinematics of a one-dimensional accelerated motion with ease and in terms of elegant geometry. Moreover, he believed, "Philosophy [i.e. physics] is written in this grand book—I mean the universe—which stands continually open to our gaze, but it cannot be understood unless one first learns to comprehend the language and interpret the characters in which it is written. It is written in the language of mathematics, and its characters are triangles, circles, and other geometrical figures, without which it is humanly impossible to understand a single word of it." In classroom practice, however, it can be difficult to reveal this mathematical heart of nature; free fall and other accelerated motions often get obscured by friction or other sources of errors. In this paper, we introduce a method of analyzing free-fall motion indirectly by evaluating the noise of freely falling metal pieces. The method connects a deeper understanding of the mathematical structure of accelerated motion with the possibility to derive a numerical value for the free-fall acceleration g.

Effects of hardness of abrasive grains on surface roughness of work piece in PVA bonded grinding wheel

International Nuclear Information System (INIS)

Nitta, S.; Takata, A.; Ishizaki, K.

2000-01-01

The purpose of this study is to clarify relation between hardness of abrasive grains and surface roughness of work piece in the case of PVA (Polyvinyl alcohol) bonded grinding wheels. Two PVA bonded grinding wheels; with diamond or silicon carbide as abrasive grains and grinding of glass and aluminum alloy was performed. The PVA bonded grinding wheels The PVA bonded grinding wheel with silicon carbide could not grind the glass. Because insufficiency in hardness, the PVA bonded grinding wheel with the diamond abrasive grains caused deep scratch on the aluminum alloy. It was found that the final surface roughness of the work piece was not proportional to the hardness of abrasive grains. The suitable hardness of abrasive grains will be obtained by the hardness of work piece. Copyright (2000) AD-TECH - International Foundation for the Advancement of Technology Ltd

Υ decay to two charm-quark jets as a probe of the color-octet mechanism

International Nuclear Information System (INIS)

Zhang Yujie; Chao Kuangta

2008-01-01

We calculate the decay rate of bottomonium to two charm-quark jets Υ→cc at the tree level and one-loop level including color-singlet and color-octet bb annihilations. We find that the short-distance coefficient of the color-octet piece is much larger than the color-singlet piece, and that the QCD correction will change the end point behavior of the charm quark jet. The color-singlet piece is strongly affected by the one-loop QCD correction. In contrast, the QCD correction to the color-octet piece is weak. Once the experiment can measure the branching ratio and energy distribution of the two charm-quark jets in the Υ decay, the result can be used to test the color-octet mechanism or give a strong constraint on the color-octet matrix elements.

In vitro synchrotron-based radiography of micro-gap formation at the implant–abutment interface of two-piece dental implants

International Nuclear Information System (INIS)

Rack, A.; Rack, T.; Stiller, M.; Riesemeier, H.; Zabler, S.; Nelson, K.

2010-01-01

Micro-radiography using hard X-ray synchrotron radiation is the first potential tool to allow an evaluation of the mechanical behavior of the dental implant–abutment complex during force application, thus enabling the enhancement of the design of dental implants which has been based on theoretical analysis to date. Micro-gap formation at the implant–abutment interface of two-piece dental implants was investigated in vitro using high-resolution radiography in combination with hard X-ray synchrotron radiation. Images were taken with the specimen under different mechanical loads of up to 100 N. The aim of this investigation was to prove the existence of micro-gaps for implants with conical connections as well as to study the mechanical behavior of the mating zone of conical implants during loading. Synchrotron-based radiography in comparison with classical laboratory radiography yields high spatial resolution in combination with high contrast even when exploiting micro-sized features in highly attenuating objects. The first illustration of a micro-gap which was previously indistinguishable by laboratory methods underlines that the complex micro-mechanical behavior of implants requires further in vitro investigations where synchrotron-based micro-imaging is one of the prerequisites

In vitro synchrotron-based radiography of micro-gap formation at the implant–abutment interface of two-piece dental implants

Energy Technology Data Exchange (ETDEWEB)

Rack, A., E-mail: arack@snafu.de [European Synchrotron Radiation Facility, Grenoble (France); Rack, T. [Charité, Department of Oral and Maxillofacial Surgery, Clinical Navigation and Robotics, Berlin (Germany); Stiller, M. [Charité, Department of Maxillofacial and Facial-Plastic Surgery, Division of Oral Medicine, Radiology and Surgery, Berlin (Germany); Riesemeier, H. [Bundesanstalt für Materialforschung und -prüfung, Division Structure Analysis, Polymer Analysis, Berlin (Germany); Zabler, S. [Technical University of Berlin, Institute for Materials Engineering (Germany); Nelson, K. [Charité, Department of Oral and Maxillofacial Surgery, Clinical Navigation and Robotics, Berlin (Germany)

2010-03-01

Micro-radiography using hard X-ray synchrotron radiation is the first potential tool to allow an evaluation of the mechanical behavior of the dental implant–abutment complex during force application, thus enabling the enhancement of the design of dental implants which has been based on theoretical analysis to date. Micro-gap formation at the implant–abutment interface of two-piece dental implants was investigated in vitro using high-resolution radiography in combination with hard X-ray synchrotron radiation. Images were taken with the specimen under different mechanical loads of up to 100 N. The aim of this investigation was to prove the existence of micro-gaps for implants with conical connections as well as to study the mechanical behavior of the mating zone of conical implants during loading. Synchrotron-based radiography in comparison with classical laboratory radiography yields high spatial resolution in combination with high contrast even when exploiting micro-sized features in highly attenuating objects. The first illustration of a micro-gap which was previously indistinguishable by laboratory methods underlines that the complex micro-mechanical behavior of implants requires further in vitro investigations where synchrotron-based micro-imaging is one of the prerequisites.

[Simultaneous intrusion and retraction of the anterior teeth using a three-piece base arch].

Science.gov (United States)

Liu, D; Bai, D; Wang, C; Sun, W; Guo, J; Xi, R

2000-06-01

To evaluate the effects of the three-piece base arch on overbite correction of Class II malocclusion. 20 patients with high angle, flared incisors were treated using a three-piece base arch appliance. The intrusion force of four upper incisors was adjusted to approximately 50 g. The line of force action was 2 mm distally to the resistant center(RC) and the retraction force was 20 g, the right and left posterior segments were joined by a palatal bar. Cephalograms were taken before treatment (T1) and six months after treatment (T2). The upper molars moved mesially 0.60 +/- 0.35 mm and the distance of the vertical extrusion was 0.80 +/- 0.52 mm. The distances of the upper central incisor retraction and intrusion were -4.20 +/- 2.12 mm and 3.10 +/- 0.54 mm respectively. The RC of the central incisor retracted -4.12 +/- 1.96 mm and intruded 3.20 +/- 0.66 mm. The axial inclination of the upper incisor-palatal plane changed from 123.21 degrees +/- 4.26 degrees to 116.00 degrees +/- 3.96 degrees. The three-piece segmented approach can effectively intrude and retract the upper anterior teeth for flared incisors and deep overbite.

Value Recovery from Waste Liquid Crystal Display Glass Cullet through Leaching: Understanding the Correlation between Indium Leaching Behavior and Cullet Piece Size

OpenAIRE

Basudev Swain; Chan Gi Lee; Hyun Seon Hong

2018-01-01

For hydrometallurgical recovery of indium from glass cullet after dismantling a waste liquid crystal display (LCD), leaching is the rudimentary stage. Though size reduction of the cullet pieces adds convenience for recycling, from an efficiency and cost-effectiveness perspective regarding leaching process development, determining the proper cullet piece size is essential. Hence, in this study, leaching efficiency of indium as a function of cullet piece size was investigated, wherein the prope...

Mechanisms of Cellular Proteostasis: Insights from Single-Molecule Approaches

Science.gov (United States)

Bustamante, Carlos J.; Kaiser, Christian M.; Maillard, Rodrigo A.; Goldman, Daniel H.; Wilson, Christian A.M.

2015-01-01

Cells employ a variety of strategies to maintain proteome homeostasis. Beginning during protein biogenesis, the translation machinery and a number of molecular chaperones promote correct de novo folding of nascent proteins even before synthesis is complete. Another set of molecular chaperones helps to maintain proteins in their functional, native state. Polypeptides that are no longer needed or pose a threat to the cell, such as misfolded proteins and aggregates, are removed in an efficient and timely fashion by ATP-dependent proteases. In this review, we describe how applications of single-molecule manipulation methods, in particular optical tweezers, are shedding new light on the molecular mechanisms of quality control during the life cycles of proteins. PMID:24895851

Hot isostatic pressing of single-crystal nickel-base superalloys: Mechanism of pore closure and effect on Mechanical properties

Directory of Open Access Journals (Sweden)

Epishin Alexander I.

2014-01-01

Full Text Available Pore annihilation was investigated in the single-crystal nickel-base superalloy CMSX-4. HIP tests at 1288 °C/103 MPa were interrupted at different times, then the specimens were investigated by TEM, metallography and density measurements. The kinetics of pore annihilation was determined. The pore closure mechanism was identified as plastic deformation on the octahedral slip systems. A model describing the kinetics of pore closure has been developed on the base of crystal plasticity and large strain theory. Mechanical tests with the superalloy CMSX-4 and the Ru-containing superalloy VGM4 showed, that HIP significantly increases the fatigue life at low temperatures but has no effect on creep strength.

T-piece resuscitators: how do they compare?

Science.gov (United States)

Hinder, Murray; McEwan, Alistair; Drevhammer, Thomas; Donaldson, Snorri; Tracy, Mark Brian

2018-05-04

The T-piece resuscitator (TPR) has seen increased use as a primary resuscitation device with newborns. Traditional TPR design uses a high resistance expiratory valve to produce positive end expiratory pressure (PEEP) or continuous positive airway pressure (CPAP) at resuscitation. A new TPR device that uses a dual flow ratio valve (fluidic flip) to produce PEEP/CPAP is now available (rPAP). We aimed to compare the measured ventilation performance of different TPR devices in a controlled bench test study. Single operator provided positive pressure ventilation to an incremental testlung compliance (Crs) model (0.5-5 mL/cmH 2 O) with five different brands of TPR device (Atom, Neopuff, rPAP, GE Panda warmer and Draeger Resuscitaire). At recommended peak inflation pressure (PIP) 20 cmH 2 O, PEEP of 5 cmH 2 O and rate of 60 inflations per minute. 1864 inflations were analysed. Four of the five devices tested demonstrated inadvertent elevations in mean PEEP (5.5-10.3 cmH 2 O, p<0.001) from set value as Crs was increased, while one device (rPAP) remained at the set value. Measured PIP exceeded the set value in two infant warmer devices (GE and Draeger) with inbuilt TPR at Crs of 0.5 (24.5 and 23.5 cmH 2 O, p<0.001). Significant differences were seen in tidal volumes across devices particularly at higher Crs (p<0.001). Results show important variation in delivered ventilation from set values due to inherent TPR device design characteristics with a range of lung compliances expected at birth. Device-generated inadvertent PEEP and overdelivery of PIP may be clinically deleterious for term and preterm newborns or infants with larger Crs during resuscitation. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Transverse mechanical properties of cell walls of single living plant cells probed by laser-generated acoustic waves.

Science.gov (United States)

Gadalla, Atef; Dehoux, Thomas; Audoin, Bertrand

2014-05-01

Probing the mechanical properties of plant cell wall is crucial to understand tissue dynamics. However, the exact symmetry of the mechanical properties of this anisotropic fiber-reinforced composite remains uncertain. For this reason, biologically relevant measurements of the stiffness coefficients on individual living cells are a challenge. For this purpose, we have developed the single-cell optoacoustic nanoprobe (SCOPE) technique, which uses laser-generated acoustic waves to probe the stiffness, thickness and viscosity of live single-cell subcompartments. This all-optical technique offers a sub-micrometer lateral resolution, nanometer in-depth resolution, and allows the non-contact measurement of the mechanical properties of live turgid tissues without any assumption of mechanical symmetry. SCOPE experiments reveal that single-cell wall transverse stiffness in the direction perpendicular to the epidermis layer of onion cells is close to that of cellulose. This observation demonstrates that cellulose microfibrils are the main load-bearing structure in this direction, and suggests strong bonding of microfibrils by hemicelluloses. Altogether our measurement of the viscosity at high frequencies suggests that the rheology of the wall is dominated by glass-like dynamics. From a comparison with literature, we attribute this behavior to the influence of the pectin matrix. SCOPE's ability to unravel cell rheology and cell anisotropy defines a new class of experiments to enlighten cell nano-mechanics.

Experimental study of micro-milling mechanism and surface quality of a nickel-based single crystal superalloy

Energy Technology Data Exchange (ETDEWEB)

Gao, Qi; Gong, Yadong; Zhou, Yun Guang; Wen, Xue Long [School of Mechanical Engineering and Automation, Northeastern University, Shenyang (China)

2017-01-15

Micro-milling is widely used as a method for machining of micro-parts with high precision and efficiency. Taking the nickel-based single-crystal superalloy DD98 as the research object, the crystal characteristics of single-crystal materials were analysed, and the removal mechanism of single-crystal micro-milled parts was described. Based on molecular dynamics, a simulation model for nickel-based single-crystal superalloy DD98 micro-milling was established. Based on the response surface method of central composite design, the influences of spindle speed, feed rate, and milling depth on the surface roughness were examined, and a second-order regression model of the DD98 surface roughness was established. Using analysis of variance and the residuals of the model, a significant influence on surface roughness was found in the following order from large to small: Feed rate, spindle speed, and milling depth. Comparisons were conducted between the micro-milling experimental values and the predicted model values for different process parameters. The results show that the model fit is relatively high, and the adaptability is good. Scanning electron microscopy analysis of the micro-milling surfaces was performed to verify the slip and the removal mechanism of single-crystal materials. These results offer a theoretical reference and experimental basis for micro-milling of single-crystal materials.

The Effect of Grain Size on Mechanical Instability in Single-Phase Li-Alloy Anodes

National Research Council Canada - National Science Library

Wolfenstine, Jeff

2000-01-01

.... The results of this study suggest that decreasing the particle and/or grain size is not a practical approach to solving the mechanical instability problem of single phase Li alloys that are intended to be used as anodes in Li-ion batteries.

One-Piece Zirconia Ceramic versus Titanium Implants in the Jaw and Femur of a Sheep Model: A Pilot Study.

Science.gov (United States)

Siddiqi, A; Duncan, W J; De Silva, R K; Zafar, S

2016-01-01

Reports have documented titanium (Ti) hypersensitivity after dental implant treatment. Alternative materials have been suggested including zirconia (Zr) ceramics, which have shown predictable osseointegration in animal studies and appear free of immune responses. The aim of the research was to investigate the bone-to-implant contact (BIC) of one-piece Zr, compared with one-piece Ti implants, placed in the jaws and femurs of domestic sheep. Ten New Zealand mixed breed sheep were used. A One-piece prototype Ti (control) and one Zr (test) implant were placed in the mandible, and one of each implant (Ti and Zr) was placed into the femoral epicondyle of each animal. The femur implants were submerged and unloaded; the mandibular implants were placed using a one-stage transgingival protocol and were nonsubmerged. After a healing period of 12 weeks, %BIC was measured. The overall survival rate for mandibular and femur implants combined was 87.5%. %BIC was higher for Zr implants versus Ti implants in the femur (85.5%, versus 78.9%) ( p = 0.002). Zirconia implants in the mandible showed comparable %BIC to titanium implants (72.2%, versus 60.3%) ( p = 0.087). High failure rate of both Zr and Ti one-piece implants in the jaw could be attributed to the one-piece design and surface characteristics of the implant that could have influenced osseointegration. Further clinical trials are recommended to evaluate the performance of zirconia implants under loading conditions.

Revealing −1 Programmed Ribosomal Frameshifting Mechanisms by Single-Molecule Techniques and Computational Methods

Directory of Open Access Journals (Sweden)

Kai-Chun Chang

2012-01-01

Full Text Available Programmed ribosomal frameshifting (PRF serves as an intrinsic translational regulation mechanism employed by some viruses to control the ratio between structural and enzymatic proteins. Most viral mRNAs which use PRF adapt an H-type pseudoknot to stimulate −1 PRF. The relationship between the thermodynamic stability and the frameshifting efficiency of pseudoknots has not been fully understood. Recently, single-molecule force spectroscopy has revealed that the frequency of −1 PRF correlates with the unwinding forces required for disrupting pseudoknots, and that some of the unwinding work dissipates irreversibly due to the torsional restraint of pseudoknots. Complementary to single-molecule techniques, computational modeling provides insights into global motions of the ribosome, whose structural transitions during frameshifting have not yet been elucidated in atomic detail. Taken together, recent advances in biophysical tools may help to develop antiviral therapies that target the ubiquitous −1 PRF mechanism among viruses.

Debris filtering effectiveness and pressure drop tests of debris resistance-bottom end piece

International Nuclear Information System (INIS)

Chung, Moon Ki; Song, Chul Hwa; Chung, Heung June; Won, Soon Yeun; Cho, Young Ro; Kim, Bok Deuk

1992-03-01

In this final report, described are the test conditions and test procedures for the debris filtering effectiveness and pressure drop tests for developing the Debris Resistance-Bottom End Piece (DR-BEP). And the test results are tabulated for later evaluation. (Author)

Experimental studies of the dynamic mechanical response of a single polymer chain

DEFF Research Database (Denmark)

Thormann, Esben; Evans, Drew R.; Craig, Vincent S. J.

2006-01-01

The high-frequency and low-amplitude dynamic mechanical response from a single poly(vinyl alcohol) chain was investigated. Modification of a commercial atomic force microscope enabled high-frequency and low-amplitude periodic deformations of polymer chains during extension to be performed...... mechanical response from poly(vinyl alcohol) does not differ from its static response. This result is not unexpected as poly(vinyl alcohol) is a highly flexible polymer with intramolecular relaxation processes taking place on a short time scale. The choice of a polymer with a fast relaxation allows its...... static properties to be recovered from the dynamic measurements and enables the method suggested in this paper for decoupling the polymer response from the hydrodynamic response to be validated....

Mechanics dictate where and how freshwater planarians fission.

Science.gov (United States)

Malinowski, Paul T; Cochet-Escartin, Olivier; Kaj, Kelson J; Ronan, Edward; Groisman, Alexander; Diamond, Patrick H; Collins, Eva-Maria S

2017-10-10

Asexual freshwater planarians reproduce by tearing themselves into two pieces by a process called binary fission. The resulting head and tail pieces regenerate within about a week, forming two new worms. Understanding this process of ripping oneself into two parts poses a challenging biomechanical problem. Because planarians stop "doing it" at the slightest disturbance, this remained a centuries-old puzzle. We focus on Dugesia japonica fission and show that it proceeds in three stages: a local constriction ("waist formation"), pulsation-which increases waist longitudinal stresses-and transverse rupture. We developed a linear mechanical model with a planarian represented by a thin shell. The model fully captures the pulsation dynamics leading to rupture and reproduces empirical time scales and stresses. It asserts that fission execution is a mechanical process. Furthermore, we show that the location of waist formation, and thus fission, is determined by physical constraints. Together, our results demonstrate that where and how a planarian rips itself apart during asexual reproduction can be fully explained through biomechanics.

Mechanics governs single-cell signaling and multi-cell robustness in biofilm infections

Science.gov (United States)

Gordon, Vernita

In biofilms, bacteria and other microbes are embedded in extracellular polymers (EPS). Multiple types of EPS can be produced by a single bacterial strain - the reasons for this redundancy are not well-understood. Our work suggests that different polymers may confer distinct mechanical benefits. Our model organism is Pseudomonas aeruginosa, an opportunistic human pathogen that forms chronic biofilm infections associated with increased antibiotic resistance and evasion of the immune defense. Biofilms initiate when bacteria attach to a surface, sense the surface, and change their gene expression. Changes in gene expression are regulated by a chemical signal, cyclic-di-GMP. We find that one EPS material, called ``PEL,'' enhances surface sensing by increasing mechanical coupling of single bacteria to the surface. Measurements of bacterial motility suggest that PEL may increase frictional interactions between the surface and the bacteria. Consistent with this, we show that bacteria increase cyclic-di-GMP signaling in response to mechanical shear stress. Mechanosensing has long been known to be important to the function of cells in higher eukaryotes, but this is one of only a handful of studies showing that bacteria can sense and respond to mechanical forces. For the mature biofilm, the embedding polymer matrix can protect bacteria both chemically and mechanically. P. aeruginosa infections in the cystic fibrosis (CF) lung often last for decades, ample time for the infecting strain(s) to evolve. Production of another EPS material, alginate, is well-known to tend to increase over time in CF infections. Alginate chemically protects biofilms, but also makes them softer and weaker. Recently, it is being increasingly recognized that bacteria in chronic CF infections also evolve to increase PSL production. We use oscillatory bulk rheology to determine the unique contributions of EPS materials to biofilm mechanics. Unlike alginate, increased PSL stiffens biofilms. Increasing both

Research on generation mechanism of single event transient current generated in the semiconductor using ion accelerator

International Nuclear Information System (INIS)

Hirao, Toshio

2007-01-01

Single-event upset (SEU) is triggered when an amount of electric charges induced by energetic ion incidence exceeds a value known as a critical charge in a very short time period. Therefore, accurate evaluation of electric charge and understanding of basic mechanism of SEU are necessary for the improvement of SEU torrance of electronic devices. In this paper, the collected charges for the single event transient current induced on semiconductor by heavy ion microbeams, and application to use microbeam for single event studies are presented. (author)

Mechanical characterization and single asperity scratch behaviour of dry zinc and manganese phosphate coatings

NARCIS (Netherlands)

Ernens, D.; de Rooij, M. B.; Pasaribu, H. R.; van Riet, E.J.; van Haaften, W.M.; Schipper, D. J.

The goal of this study is to characterise the mechanical properties of zinc and manganese phosphate coatings before and after running in. The characterization is done with nano-indentation to determine the individual crystal hardness and single asperity scratch tests to investigate the deformation

Near surface mechanical properties of optical single crystals and surface response to deterministic microgrinding

Science.gov (United States)

Randi, Joseph A., III

2005-12-01

This thesis makes use of microindentation, nanoindentation and nanoscratching methods to better understand the mechanical properties of single crystalline silicon, calcium fluoride, and magnesium fluoride. These properties are measured and are used to predict the material's response to material removal, specifically by grinding and polishing, which is a combination of elastic, plastic and fracture processes. The hardness anisotropy during Knoop microindentation, hardness from nanoindentation, and scratch morphology from nanoscratching are reported. This information is related to the surface microroughness from grinding. We show that mechanical property relationships that predict the surface roughness from lapping and deterministic microgrinding of optical glasses are applicable to single crystals. We show the range of hardness from some of the more common crystallographic faces. Magnesium fluoride, having a tetragonal structure, has 2-fold hardness anisotropy. Nanoindentation, as expected provides higher hardness than microindentation, but anisotropy is not observed. Nanoscratching provides the scratch profile during loading, after the load has been removed, and the coefficient of friction during the loading. Ductile and brittle mode scratching is present with brittle mode cracking being orientation specific. Subsurface damage (SSD) measurements are made using a novel process known as the MRF technique. Magnetorheological finishing is used to polish spots into the ground surface where SSD can be viewed. SSD is measured using an optical microscope and knowledge of the spot profile. This technique is calibrated with a previous technique and implemented to accurately measure SSD in single crystals. The data collected are compared to the surface microroughness of the ground surface, resulting in an upper bound relationship. The results indicate that SSD is always less than 1.4 times the peak-to-valley surface microroughness for single crystals regardless of the

Patient’s satisfaction after 2-piece inflatable penile prosthesis implantation: An Italian multicentric study

Directory of Open Access Journals (Sweden)

Giorgio Gentile

2016-03-01

Full Text Available Introduction: Penile prosthesis implant represents a valuable solution for pts with severe erectile dysfunction (ED, non-responders to medical management. The aim of our study was to evaluate the satisfaction of patients (pts after 2-pieces inflatable penile prosthesis (IPP. Aim of the study: to evaluate safety, reliability and post-operative patient’s satisfaction after implantation of two-pieces IPP. Materials and Methods: This retrospective multicentric analysis concerns a group of 42 patients undergone 2-pieces IPP implantation from November 2005 to November 2013, in four Centers of proven experience. As a first step, a detailed review of all clinical reports was performed. Secondly, every patient was asked to fill the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS specifically modified, in order to assess their own satisfaction after surgery and, its impact on patient’s quality of sexual life. Results: 42 pts were evaluated (AMS-Ambicor: 28; Coloplast- Excell: 14; mean age, at time of operation: 60,7 years; mean follow up: 27,6 months; etiology of ED: vascular 23,8%, diabetes 19%, La Peyronie D. 7,1%, consequence of radical prostatectomy 31%, consequence of other pelvic surgery 11,9%, spinal trauma 7%. Mean operative time: 117 ± 58 min, mean postoperative hospital stay 3 ± 1,6 days. Post operative short-term complications: 4 pts (9,5%. Post operative long-term complications: 4 pts (9,5%. Long-term functional results (Questionnaire: 71% of pts (30 reported regular use of the prosthesis, at least 1 time/week, the satisfaction was good in 42% of pts (18, quite good in 33,3% (14, quite bad in 2,4% (1, very bad in 7,1% (3, 6 pts (14,4% didn’t answer. Conclusions: 2 pieces IPP appears to be associated with a low complication rate and good satisfaction of pts especially in the elderly. It also assures satisfactory rates of aesthetics and functional results.

Study on pipe wastage mechanism by liquid droplet impingement erosion

International Nuclear Information System (INIS)

Higashi, Yuma; Narabayashi, Tadashi; Shimazu, Yoichiro; Tsuji, Masashi; Ohmori, Shuichi; Mori, Michitsugu; Tezuka, Kenichi

2009-01-01

Evaluation of wastage speed for nuclear power plant maintains plant reliability and power up rating is important. There are two main cause of wastage flow accelerated corrosion (FAC) and mechanical erosion. This study is to develop evaluating the wastage speed by liquid droplet impingement erosion (LDIE). LDIE often occurs at downstream of corner of pipe or orifice. In this study, the liquid drop impinging tests were conducted with the test pieces mounted on a high speed rotating disk that cross thin water down jet and produced LDIE phenomena. The amount of the wastage by LDIE was evaluated by changing the rotational speed, the impingement frequency, and test piece materials. In addition, the generation mechanism of erosion was investigated by observing the surface of the test piece with a microscope. There is a method of evaluating by the mass difference before and after experiments. But this method is not correct because error becomes larger for mass measurement in the experiment, for the lost mass by LDIE is very little amount. Therefore, the method was developed to measure the volume in the erosion part. In this method, depth of LDIE was measured by the accuracy of ±0.01μm; therefore accurate measurement of the wastage can be improved. (author)

Keeping All the PIECES: Phylogenetically Informed Ex Situ Conservation of Endangered Species.

Science.gov (United States)

Larkin, Daniel J; Jacobi, Sarah K; Hipp, Andrew L; Kramer, Andrea T

2016-01-01

Ex situ conservation in germplasm and living collections is a major focus of global plant conservation strategies. Prioritizing species for ex situ collection is a necessary component of this effort for which sound strategies are needed. Phylogenetic considerations can play an important role in prioritization. Collections that are more phylogenetically diverse are likely to encompass more ecological and trait variation, and thus provide stronger conservation insurance and richer resources for future restoration efforts. However, phylogenetic criteria need to be weighed against other, potentially competing objectives. We used ex situ collection and threat rank data for North American angiosperms to investigate gaps in ex situ coverage and phylogenetic diversity of collections and to develop a flexible framework for prioritizing species across multiple objectives. We found that ex situ coverage of 18,766 North American angiosperm taxa was low with respect to the most vulnerable taxa: just 43% of vulnerable to critically imperiled taxa were in ex situ collections, far short of a year-2020 goal of 75%. In addition, species held in ex situ collections were phylogenetically clustered (P species been drawn at random. These patterns support incorporating phylogenetic considerations into ex situ prioritization in a manner balanced with other criteria, such as vulnerability. To meet this need, we present the 'PIECES' index (Phylogenetically Informed Ex situ Conservation of Endangered Species). PIECES integrates phylogenetic considerations into a flexible framework for prioritizing species across competing objectives using multi-criteria decision analysis. Applying PIECES to prioritizing ex situ conservation of North American angiosperms, we show strong return on investment across multiple objectives, some of which are negatively correlated with each other. A spreadsheet-based decision support tool for North American angiosperms is provided; this tool can be customized to

Multi-physics modeling of single/multiple-track defect mechanisms in electron beam selective melting

International Nuclear Information System (INIS)

Yan, Wentao; Ge, Wenjun; Qian, Ya; Lin, Stephen; Zhou, Bin; Liu, Wing Kam; Lin, Feng; Wagner, Gregory J.

2017-01-01

Metallic powder bed-based additive manufacturing technologies have many promising attributes. The single track acts as one fundamental building unit, which largely influences the final product quality such as the surface roughness and dimensional accuracy. A high-fidelity powder-scale model is developed to predict the detailed formation processes of single/multiple-track defects, including the balling effect, single track nonuniformity and inter-track voids. These processes are difficult to observe in experiments; previous studies have proposed different or even conflicting explanations. Our study clarifies the underlying formation mechanisms, reveals the influence of key factors, and guides the improvement of fabrication quality of single tracks. Additionally, the manufacturing processes of multiple tracks along S/Z-shaped scan paths with various hatching distance are simulated to further understand the defects in complex structures. The simulations demonstrate that the hatching distance should be no larger than the width of the remelted region within the substrate rather than the width of the melted region within the powder layer. Thus, single track simulations can provide valuable insight for complex structures.

Mechanical Properties of Commercial Carbon Fibers Using a Single Filament Tensile Test

International Nuclear Information System (INIS)

Joh, Han-Ik; Song, Hae Kyung; Ku, Bon-Cheol; Lee, Sungho; Kim, Ki-Young; Kang, Phil-Hyun

2013-01-01

In this study, mechanical properties of commercial carbon fibers were evaluated using a single filament tensile test with various fiber gauge lengths. Tensile strength increased significantly with a decreasing length of the test specimens possibly due to small defect sites. The compliance method provided more accurate moduli of the carbon fibers, removing system errors during the single filament tensile test. The Weibull modulus revealed that shorter specimens had an inhomogeneous defect distribution, leading to a higher tensile strength and its standard deviation. X-ray diffractograms of carbon fibers showed a similar crystallinity and orientation in spite of significant differences in the fiber modulus and strength, indicating that crystalline structure of the commercial carbon fibers used in the study was not attributable to the difference in their tensile properties.

A robust single-beam optical trap for a gram-scale mechanical oscillator.

Science.gov (United States)

Altin, P A; Nguyen, T T-H; Slagmolen, B J J; Ward, R L; Shaddock, D A; McClelland, D E

2017-11-06

Precise optical control of microscopic particles has been mastered over the past three decades, with atoms, molecules and nano-particles now routinely trapped and cooled with extraordinary precision, enabling rapid progress in the study of quantum phenomena. Achieving the same level of control over macroscopic objects is expected to bring further advances in precision measurement, quantum information processing and fundamental tests of quantum mechanics. However, cavity optomechanical systems dominated by radiation pressure - so-called 'optical springs' - are inherently unstable due to the delayed dynamical response of the cavity. Here we demonstrate a fully stable, single-beam optical trap for a gram-scale mechanical oscillator. The interaction of radiation pressure with thermo-optic feedback generates damping that exceeds the mechanical loss by four orders of magnitude. The stability of the resultant spring is robust to changes in laser power and detuning, and allows purely passive self-locking of the cavity. Our results open up a new way of trapping and cooling macroscopic objects for optomechanical experiments.

Transcending the biomarker mindset: deciphering disease mechanisms at the single cell level.

Science.gov (United States)

Danna, Erika A; Nolan, Garry P

2006-02-01

The application of proteomics to disease research promises to enhance the understanding and treatment of many human maladies through the identification of molecular profiles associated with each disease. However, although much is made of the utility of molecular signatures as markers of disease state, insufficient emphasis is often placed on the simultaneous need for biological mechanism inquiry. Focused and detailed analyses of disease-associated signaling networks have the potential to be more mechanistically informative than large-scale proteomic profiling approaches, providing insight into the cellular processes involved in pathogenesis, disease progression and therapeutic resistance; while still providing diagnostic or clinical management direction. Phospho-specific flow cytometry provides a method for the analysis of pathological signaling networks, enabling the investigation of disease mechanisms at the single-cell level.

Multiple piece turbine engine airfoil with a structural spar

Science.gov (United States)

Vance, Steven J [Orlando, FL

2011-10-11

A multiple piece turbine airfoil having an outer shell with an airfoil tip that is attached to a root with an internal structural spar is disclosed. The root may be formed from first and second sections that include an internal cavity configured to receive and secure the one or more components forming the generally elongated airfoil. The internal structural spar may be attached to an airfoil tip and place the generally elongated airfoil in compression. The configuration enables each component to be formed from different materials to reduce the cost of the materials and to optimize the choice of material for each component.

Integration of Plasticity Mechanisms within a Single Sensory Neuron of C. elegans Actuates a Memory.

Science.gov (United States)

Hawk, Josh D; Calvo, Ana C; Liu, Ping; Almoril-Porras, Agustin; Aljobeh, Ahmad; Torruella-Suárez, María Luisa; Ren, Ivy; Cook, Nathan; Greenwood, Joel; Luo, Linjiao; Wang, Zhao-Wen; Samuel, Aravinthan D T; Colón-Ramos, Daniel A

2018-01-17

Neural plasticity, the ability of neurons to change their properties in response to experiences, underpins the nervous system's capacity to form memories and actuate behaviors. How different plasticity mechanisms act together in vivo and at a cellular level to transform sensory information into behavior is not well understood. We show that in Caenorhabditis elegans two plasticity mechanisms-sensory adaptation and presynaptic plasticity-act within a single cell to encode thermosensory information and actuate a temperature preference memory. Sensory adaptation adjusts the temperature range of the sensory neuron (called AFD) to optimize detection of temperature fluctuations associated with migration. Presynaptic plasticity in AFD is regulated by the conserved kinase nPKCε and transforms thermosensory information into a behavioral preference. Bypassing AFD presynaptic plasticity predictably changes learned behavioral preferences without affecting sensory responses. Our findings indicate that two distinct neuroplasticity mechanisms function together through a single-cell logic system to enact thermotactic behavior. VIDEO ABSTRACT. Copyright © 2017 Elsevier Inc. All rights reserved.

The action of chemical and mechanical stresses on single and dual species biofilm removal of drinking water bacteria.

Science.gov (United States)

Gomes, I B; Lemos, M; Mathieu, L; Simões, M; Simões, L C

2018-08-01

The presence of biofilms in drinking water distribution systems (DWDS) is a global public health concern as they can harbor pathogenic microorganisms. Sodium hypochlorite (NaOCl) is the most commonly used disinfectant for microbial growth control in DWDS. However, its effect on biofilm removal is still unclear. This work aims to evaluate the effects of the combination of chemical (NaOCl) and mechanical stresses on the removal of single and dual species biofilms of two bacteria isolated from DWDS and considered opportunistic, Acinectobacter calcoaceticus and Stenotrophomonas maltophilia. A rotating cylinder reactor was successfully used for the first time in drinking water biofilm studies with polyvinyl chloride as substratum. The single and dual species biofilms presented different characteristics in terms of metabolic activity, mass, density, thickness and content of proteins and polysaccharides. Their complete removal was not achieved even when a high NaOCl concentrations and an increasing series of shear stresses (from 2 to 23Pa) were applied. In general, NaOCl pre-treatment did not improve the impact of mechanical stress on biofilm removal. Dual species biofilms were colonized mostly by S. maltophilia and were more susceptible to chemical and mechanical stresses than these single species. The most efficient treatment (93% biofilm removal) was the combination of NaOCl at 175mg·l -1 with mechanical stress against dual species biofilms. Of concern was the high tolerance of S. maltophilia to chemical and mechanical stresses in both single and dual species biofilms. The overall results demonstrate the inefficacy of NaOCl on biofilm removal even when combined with high shear stresses. Copyright © 2018 Elsevier B.V. All rights reserved.

Multiple environment single system quantum mechanical/molecular mechanical (MESS-QM/MM) calculations. 1. Estimation of polarization energies.

Science.gov (United States)

Sodt, Alexander J; Mei, Ye; König, Gerhard; Tao, Peng; Steele, Ryan P; Brooks, Bernard R; Shao, Yihan

2015-03-05

In combined quantum mechanical/molecular mechanical (QM/MM) free energy calculations, it is often advantageous to have a frozen geometry for the quantum mechanical (QM) region. For such multiple-environment single-system (MESS) cases, two schemes are proposed here for estimating the polarization energy: the first scheme, termed MESS-E, involves a Roothaan step extrapolation of the self-consistent field (SCF) energy; whereas the other scheme, termed MESS-H, employs a Newton-Raphson correction using an approximate inverse electronic Hessian of the QM region (which is constructed only once). Both schemes are extremely efficient, because the expensive Fock updates and SCF iterations in standard QM/MM calculations are completely avoided at each configuration. They produce reasonably accurate QM/MM polarization energies: MESS-E can predict the polarization energy within 0.25 kcal/mol in terms of the mean signed error for two of our test cases, solvated methanol and solvated β-alanine, using the M06-2X or ωB97X-D functionals; MESS-H can reproduce the polarization energy within 0.2 kcal/mol for these two cases and for the oxyluciferin-luciferase complex, if the approximate inverse electronic Hessians are constructed with sufficient accuracy.

Brief report: Examining children's disruptive behavior in the wake of trauma - A two-piece growth curve model before and after a school shooting.

Science.gov (United States)

Liao, Yue; Shonkoff, Eleanor T; Barnett, Elizabeth; Wen, C K Fred; Miller, Kimberly A; Eddy, J Mark

2015-10-01

School shootings may have serious negative impacts on children years after the event. Previous research suggests that children exposed to traumatic events experience heightened fear, anxiety, and feelings of vulnerability, but little research has examined potential aggressive and disruptive behavioral reactions. Utilizing a longitudinal dataset in which a local school shooting occurred during the course of data collection, this study sought to investigate whether the trajectory of disruptive behaviors was affected by the shooting. A two-piece growth curve model was used to examine the trajectory of disruptive behaviors during the pre-shooting years (i.e., piece one) and post-shooting years (i.e., piece two). Results indicated that the two-piece growth curve model fit the data better than the one-piece model and that the school shooting precipitated a faster decline in aggressive behaviors. This study demonstrated a novel approach to examining effects of an unexpected traumatic event on behavioral trajectories using an existing longitudinal data set. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Brief Report: Examining children’s disruptive behavior in the wake of trauma - A two-piece growth curve model before and after a school shooting

Science.gov (United States)

Liao, Yue; Shonkoff, Eleanor T.; Barnett, Elizabeth; Wen, CK Fred; Miller, Kimberly A.; Eddy, J. Mark

2015-01-01

School shootings may have serious negative impacts on children years after the event. Previous research suggests that children exposed to traumatic events experience heightened fear, anxiety, and feelings of vulnerability, but little research has examined potential aggressive and disruptive behavioral reactions. Utilizing a longitudinal dataset in which a local school shooting occurred during the course of data collection, this study sought to investigate whether the trajectory of disruptive behaviors was affected by the shooting. A two-piece growth curve model was used to examine the trajectory of disruptive behaviors during the pre-shooting years (i.e., piece one) and post-shooting years (i.e., piece two). Results indicated that the two-piece growth curve model fit the data better than the one-piece model and that the school shooting precipitated a faster decline in aggressive behaviors. This study demonstrated a novel approach to examining effects of an unexpected traumatic event on behavioral trajectories using an existing longitudinal data set. PMID:26298676

Surgical management of cross-bites in orthognathic surgery: Surgically assisted rapid maxillary expansion (SARME) versus two-piece maxilla.

Science.gov (United States)

Seeberger, Robin; Gander, Evelyn; Hoffmann, Jürgen; Engel, Michael

2015-09-01

The surgical treatment of cross-bites includes surgically-assisted maxillary expansion (SARME) or maxillary-bipartition during bimaxillary surgery. This study evaluates and compares the changes in the teeth and lower nasal passage, as well as the stability of the expansion. The measurements were performed on the cone-beam computed tomography (CBCT) scans of 32 patients with transverse (width) deficiencies of the maxilla. To expand the maxilla, 12 patients underwent the two-piece maxilla method, while 20 patients received SARME. The mean distraction width for SARME was 6.8 mm (SD 3.7), while that for the two-piece maxilla was 4.1 mm (SD 1.6). The expansion with SARME was over the entire length of the maxilla, from anterior to posterior, whereas the expansion of the two-piece patient group was only in the posterior part of the maxilla. The segments of the maxilla opened nearly parallel in SARME, while they were reverse V-shaped in the two-piece maxilla, from anterior to posterior. A key point in the planning of combined orthodontic-orthognathic therapy with surgical correction of a cross-bite is the precise determination of the area where the width needs to be increased, and the amount of correction needed to treat the patient using minimal surgical procedures. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

The last piece of the ring

CERN Multimedia

2008-01-01

In a sequel to the recent success at CMS, the last section of the LHC beam vacuum system was installed in ATLAS on Monday 16 June. The place where experiment and accelerator meet, the completion of the last part of the continuous 27 km beampipe signals how near the LHC is to the circulation of its first beam. Watch the video! The last section of the LHC beampipe being installed in ATLAS.Although a seemingly simple piece of technology in comparison with the complexity of the detectors, the beampipe is a carefully designed and essential part of both the experiments and the LHC. The section of beam pipe that completed the LHC ring on Monday 16 June is about 20 metres from the centre of ATLAS, very close to where the first magnets of the LHC are located. Unlike the central ATLAS beampipe, which is made of beryllium, the final section is made of stainless steel. An aluminium cone surrounds the stainless steel tube with the super slim...

PuzzleArt Therapy: Connecting the Pieces in Search of Answers

Directory of Open Access Journals (Sweden)

Jennifer Fortuna

2016-10-01

Full Text Available Alli Berman, a New York based artist, provided the cover art for the Fall 2016 issue of The Open Journal of Occupational Therapy (OJOT. “Sunlight Underwater” is a 12 piece PuzzleArt painting made from acrylic on American maple that measures 22x30. The PuzzleArt concept began as a simple exercise that evolved into a therapeutic modality. When a sudden stroke impacted Berman’s well-being and quality of life, it was art that helped her to make connections during recovery.

FEA analysis and design optimization for a multifunctional piece of furniture

Directory of Open Access Journals (Sweden)

Haraga Georgeta

2017-01-01

Full Text Available The paper presents an original approach to the integration of computer aided design and finite element analysis for a multifunctional piece of furniture using CATIA Generative Structural Analysis workbench. Finite Element Analysis (FEA application is an important engineering technique in the furniture industry. FEA is an accurate method for numerical solution of field problems. A major problem of mesh generation today is access to CAD geometry in a efficient and precise manner. Starting with a solid modelling for the creation of the desired piece of multifunctional furniture is used in this case, the automatic generation of the finite element meshes. Getting more accurate results for the mesh refinement process can be made by changing parameters. The article outlines the developed model for analysing the supporting structure of the armchair. This model provides simulating of the different loads and checking the raised stresses and deformation in the structures analysed. The main objective of this research is to evaluate strength of wooden cedar armchair for a person weighing 140 kg and for this the finite element analysis (FEA has been used. Multifunctional furniture is the answer to the challenges contemporary lifestyle, creativity in design activities that require optimal space utilization and reducing costs.

FEA analysis and design optimization for a multifunctional piece of furniture

OpenAIRE

Haraga Georgeta; Goanță Adrian Mihai

2017-01-01

The paper presents an original approach to the integration of computer aided design and finite element analysis for a multifunctional piece of furniture using CATIA Generative Structural Analysis workbench. Finite Element Analysis (FEA) application is an important engineering technique in the furniture industry. FEA is an accurate method for numerical solution of field problems. A major problem of mesh generation today is access to CAD geometry in a efficient and precise manner. Starting with...

Triggering Mechanism for Neutron Induced Single-Event Burnout in Power Devices

Science.gov (United States)

Shoji, Tomoyuki; Nishida, Shuichi; Hamada, Kimimori

2013-04-01

Cosmic ray neutrons can trigger catastrophic failures in power devices. It has been reported that parasitic transistor action causes single-event burnout (SEB) in power metal-oxide-semiconductor field-effect transistors (MOSFETs) and insulated gate bipolar transistors (IGBTs). However, power diodes do not have an inherent parasitic transistor. In this paper, we describe the mechanism triggering SEB in power diodes for the first time using transient device simulation. Initially, generated electron-hole pairs created by incident recoil ions generate transient current, which increases the electron density in the vicinity of the n-/n+ boundary. The space charge effect of the carriers leads to an increase in the strength of the electric field at the n-/n+ boundary. Finally, the onset of impact ionization at the n-/n+ boundary can trigger SEB. Furthermore, this failure is closely related to diode secondary breakdown. It was clarified that the impact ionization at the n-/n+ boundary is a key point of the mechanism triggering SEB in power devices.

Multiple sclerosis pathogenesis: missing pieces of an old puzzle.

Science.gov (United States)

Rahmanzadeh, Reza; Brück, Wolfgang; Minagar, Alireza; Sahraian, Mohammad Ali

2018-06-08

Traditionally, multiple sclerosis (MS) was considered to be a CD4 T cell-mediated CNS autoimmunity, compatible with experimental autoimmune encephalitis model, which can be characterized by focal lesions in the white matter. However, studies of recent decades revealed several missing pieces of MS puzzle and showed that MS pathogenesis is more complex than the traditional view and may include the following: a primary degenerative process (e.g. oligodendroglial pathology), generalized abnormality of normal-appearing brain tissue, pronounced gray matter pathology, involvement of innate immunity, and CD8 T cells and B cells. Here, we review these findings and discuss their implications in MS pathogenesis.

Dynamic Non-Rigid Objects Reconstruction with a Single RGB-D Sensor

Directory of Open Access Journals (Sweden)

Sen Wang

2018-03-01

Full Text Available This paper deals with the 3D reconstruction problem for dynamic non-rigid objects with a single RGB-D sensor. It is a challenging task as we consider the almost inevitable accumulation error issue in some previous sequential fusion methods and also the possible failure of surface tracking in a long sequence. Therefore, we propose a global non-rigid registration framework and tackle the drifting problem via an explicit loop closure. Our novel scheme starts with a fusion step to get multiple partial scans from the input sequence, followed by a pairwise non-rigid registration and loop detection step to obtain correspondences between neighboring partial pieces and those pieces that form a loop. Then, we perform a global registration procedure to align all those pieces together into a consistent canonical space as guided by those matches that we have established. Finally, our proposed model-update step helps fixing potential misalignments that still exist after the global registration. Both geometric and appearance constraints are enforced during our alignment; therefore, we are able to get the recovered model with accurate geometry as well as high fidelity color maps for the mesh. Experiments on both synthetic and various real datasets have demonstrated the capability of our approach to reconstruct complete and watertight deformable objects.

Temperature-dependent mechanical properties of single-layer molybdenum disulphide: Molecular dynamics nanoindentation simulations

Energy Technology Data Exchange (ETDEWEB)

Zhao, Junhua, E-mail: junhua.zhao@uni-weimar.de [Jiangsu Province Key Laboratory of Advanced Manufacturing Equipment and Technology of Food, Jiangnan University, 214122 Wuxi (China); Institute of Structural Mechanics, Bauhaus-University Weimar, 99423 Weimar (Germany); Jiang, Jin-Wu, E-mail: jwjiang5918@hotmail.com [Institute of Structural Mechanics, Bauhaus-University Weimar, 99423 Weimar (Germany); Rabczuk, Timon, E-mail: timon.rabczuk@uni-weimar.de [Institute of Structural Mechanics, Bauhaus-University Weimar, 99423 Weimar (Germany); School of Civil, Environmental and Architectural Engineering, Korea University, 136-701 Seoul (Korea, Republic of)

2013-12-02

The temperature-dependent mechanical properties of single-layer molybdenum disulphide (MoS{sub 2}) are obtained using molecular dynamics (MD) nanoindentation simulations. The Young's moduli, maximum load stress, and maximum loading strain decrease with increasing temperature from 4.2 K to 500 K. The obtained Young's moduli are in good agreement with those using our MD uniaxial tension simulations and the available experimental results. The tendency of maximum loading strain with different temperature is opposite with that of metal materials due to the short range Stillinger-Weber potentials in MoS{sub 2}. Furthermore, the indenter tip radius and fitting strain effect on the mechanical properties are also discussed.

Comparison of the external physical damages between laser-assisted and mechanical immobilized human sperm using scanning electronic microscopy.

Directory of Open Access Journals (Sweden)

David Y L Chan

Full Text Available We aim to visualize the external physical damages and distinct external phenotypic effects between mechanical and laser-assisted immobilized human spermatozoa using scanning electronic microscopy (SEM. Human spermatozoa were immobilized mechanically or with laser assistance for SEM examination and the membrane integrities were checked on both types of immobilized spermatozoa. We found evidence of external damages at SEM level on mechanically kinked sperm, but not on laser-assisted immobilized sperm. Although no external damage was found on laser-assist immobilized sperm, there were two distinct types of morphological changes when spermatozoa were stricken by infra-red laser. Coiled tails were immediately formed when Laser pulse was applied to the sperm end piece area, whereas laser applied to the sperm principal piece area resulted in a sharp bend of sperm tails. Sperm immobilized by laser did not exhibit any morphological change if the laser did not hit within the on-screen central target zone or if the laser hit the sperm mid piece or head. Our modified membrane integrity assay revealed that the external membrane of more than half of the laser-assisted immobilized sperm remained intact. In conclusion, mechanical immobilization produced membrane damages whilst laser-assisted immobilization did not result in any external membrane damages besides morphological changes at SEM level.

Apparatus of irradiation of steel test pieces in the Marcoule pile G 1

International Nuclear Information System (INIS)

Marinot, R.; Wallet, Ph.

1960-01-01

Test pieces of steel were irradiated in the reactor G1 at Marcoule, in convectors replacing fuel elements, and in vertical channels in furnace-heated containers. The apparatus designed for this irradiation is described: containers, converter-rods, suspension fixtures and clamps, temperature measurement devices, lead castles and unloading set-ups. (author) [fr

Continuous quantum mechanics of single particles in closed and quasi-closed systems: Pt. 1 and 2

International Nuclear Information System (INIS)

Brieger, M.

2004-01-01

The established statistical interpretation of quantum mechanics never envisioned our today's ability to handle and investigate single particles in trap devices. After scrutinizing the development of quantum mechanics, we point out that Schroedinger's equation establishes an energy representation, which obtains the energy eigenvalues as extrema of the energy curve or on the energy hypersurface, respectively. We also strongly emphasize its never exhausted capability of accounting in classical terms and full detail for the dynamics of single particles in closed systems. This is demonstrated for several familiar examples. They show that the eigensolutions to Schroedinger's equation must not blindly be identified with physically stationary states. The gained insight into the true dynamics allows to describe, without involving QED, the time evolution of a complete spontaneous transition as being driven by unbalanced internal dynamics. This mechanism relies on the fact that perfect balances are only possible in the exact extrema of the total energy and that any deviation, which is characterized by nonstationary states, makes multipole moments oscillate and emit electromagnetic radiation. (orig.)

Continuous quantum mechanics of single particles in closed and quasi-closed systems: Pt. 1 and 2

Energy Technology Data Exchange (ETDEWEB)

Brieger, M. [DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Stuttgart (Germany). Inst. fuer Technische Physik

2004-07-01

The established statistical interpretation of quantum mechanics never envisioned our today's ability to handle and investigate single particles in trap devices. After scrutinizing the development of quantum mechanics, we point out that Schroedinger's equation establishes an energy representation, which obtains the energy eigenvalues as extrema of the energy curve or on the energy hypersurface, respectively. We also strongly emphasize its never exhausted capability of accounting in classical terms and full detail for the dynamics of single particles in closed systems. This is demonstrated for several familiar examples. They show that the eigensolutions to Schroedinger's equation must not blindly be identified with physically stationary states. The gained insight into the true dynamics allows to describe, without involving QED, the time evolution of a complete spontaneous transition as being driven by unbalanced internal dynamics. This mechanism relies on the fact that perfect balances are only possible in the exact extrema of the total energy and that any deviation, which is characterized by nonstationary states, makes multipole moments oscillate and emit electromagnetic radiation. (orig.)

Dynamic strain-mediated coupling of a single diamond spin to a mechanical resonator

OpenAIRE

Ovartchaiyapong, Preeti; Lee, Kenneth W.; Myers, Bryan A.; Jayich, Ania C. Bleszynski

2014-01-01

The development of hybrid quantum systems is central to the advancement of emerging quantum technologies, including quantum information science and quantum-assisted sensing. The recent demonstration of high quality single-crystal diamond resonators has led to significant interest in a hybrid system consisting of nitrogen-vacancy center spins that interact with the resonant phonon modes of a macroscopic mechanical resonator through crystal strain. However, the nitrogen-vacancy spin-strain inte...

One-Piece Implant-Retained Mandibular Overdentures By Pre-Fabricated Titanium Telescopic Attachments and Frictional Varnish: A Two-Year Prospective Study.

Science.gov (United States)

Nik, Shahram Namjoy; Nejatian, Touraj

2016-12-01

Clinical efficiency of one-piece screw-type implants with telescopic were attachments evaluated in this study. Twenty-four patients received a mandibular implant-supported overdenture and maxillary complete denture. Ninety-six one-piece implants were inserted in the inter-foraminal area. Implants were immediately loaded with an implant-retained overdenture and telescopic attachments which had frictional retention elements. There was 0.25±0.24 mm, 0.32±0.25 mm, 0.43±0.30 mm, 0.61±0.30 mm and of bone resorption after 3, 6, 12 and 24 months, respectively. The need to activate the frictional retention was the most common complication. Treatment outcomes for prefabricated telescopic retained overdentures on one-piece implants are similar to that obtained in cases of delayed loading. Copyright© 2016 Dennis Barber Ltd.

Computer Tool for Automatically Generated 3D Illustration in Real Time from Archaeological Scanned Pieces

Directory of Open Access Journals (Sweden)

Luis López

2012-11-01

Full Text Available The graphical documentation process of archaeological pieces requires the active involvement of a professional artist to recreate beautiful illustrations using a wide variety of expressive techniques. Frequently, the artist’s work is limited by the inconvenience of working only with the photographs of the pieces he is going to illustrate. This paper presents a software tool that allows the easy generation of illustrations in real time from 3D scanned models. The developed interface allows the user to simulate very elaborate artistic styles through the creation of diagrams by using the available virtual lights. The software processes the diagrams to render an illustration from any given angle or position. Among the available virtual lights, there are well known techniques as silhouettes enhancement, hatching or toon shading.

Study of ancient Islamic gilded pieces combining PIXE-RBS on external microprobe with sem images

International Nuclear Information System (INIS)

Ynsa, M.D.; Gutierrez, P.C.; Enguita, O.; Chamon, J.; Pardo, A.I.; Arroyo, M.; Barrio, J.; Gomez-Morilla, I.; Ferretti, M.; Climent-Font, A.

2008-01-01

Numerous metallic objects with very aesthetic and technological qualities have been recovered by archaeological excavations. Adequate processes of restoration and conservation treatments require the accurate determination of the elemental composition and distribution within the objects, as well as the identification of the nature and distribution of the corrosion products. Ideally the identification method should cause no alteration in the sample. In this work, different archaeological pieces with a gilded look have been characterized using simultaneously PIXE and RBS at the CMAM external microprobe in order to study the gilding metalworking done in the Iberian Peninsula during the Middle Ages. The gold layer thickness and its elemental concentrations of Ag, Au and Hg were determined by both techniques and compared with the scanning electron microscopy images obtained for some fragments of pieces. (orig.)

Numerical Simulation of a Grinding Process for the Spatial Work-pieces: a Model of the Workpiece and Grinding Wheel

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I. A. Kiselev

2015-01-01

Full Text Available The paper describes a spatial grinding dynamics mathematical model. This model includes a grinding wheel dynamics model, a work-piece dynamics model, and a numerical algorithm of geometric modeling as well. The geometric modeling algorithm is based on the Z-buffer method with author’s modifications. This algorithm allows us to simulate the formation of a new workpiece surface when removing material and as well as to determine the cutting layer thickness for each abrasive grain of the grinding wheel. The use of the surface cell bilinear approximation and the simultaneous use of multiple projection directions are the special features of the algorithm. These features improve modeling quality of machined surface. The grinding wheel model is represented as cutting micro-edges (grains set. Abrasive grains are randomly distributed on the wheel outer surface. Grains size, shape, wheel structure and graininess are taken into account. To determine the uncut chip thickness, which is cut off by each grain of the grinding wheel is used the algorithm, which finds intersection point of uncut work-piece surface with radial ray passing through the grain cutting edge. Grinding forces for each grain are defined based on the cutting layer thickness value using the phenomenological models described in the literature. Using transformations described in the article, grinding forces determined for each grain are reduced to the total grinding force, which acts on the tool and machined work-piece in the appropriate coordinate systems. Work-piece dynamics is modeled with the help of the finite element method using quadratic tetrahedral elements. The described model of spatial grinding dynamics makes it possible to evaluate the level of vibration and grinding forces, as well as the shape errors and surface quality of machined work-piece.

Different diffusion mechanisms of oxygen in ReBa{sub 2}Cu{sub 3}O{sub 7−x} (Re = Y, Ho) single crystals

Energy Technology Data Exchange (ETDEWEB)

Vovk, R.V.; Boiko, Y.I.; Bogdanov, V.V.; Kamchatnaya, S.N.; Goulatis, I.L. [V. N. Karazin Kharkiv National University, 4 Svobody sq., 61077 Kharkiv (Ukraine); Chroneos, A. [Faculty of Engineering, Environment and Computing, Coventry University, Priory Street, Coventry CV1 5FB (United Kingdom); Department of Materials, Imperial College London, London SW7 2AZ (United Kingdom)

2017-05-15

Highlights: • Single file diffusion mechanism of oxygen ions. • Ho modifies the diffusion mechanism in the oxygen sublattice. • Ho changes the efficient interaction of ions in CuO-planes. - Abstract: In the present study, the time dependencies of the resistivity of ReBa{sub 2}Cu{sub 3}O{sub 7−x} (Re=Y, Ho) single crystals with varying degree of deviation from oxygen stoichiometry was investigated. It was shown that the accelerated transport of oxygen ions in the initial stage of the process can be carried out along the one-dimensional non-stoichiometric vacancies’ accumulation by the single file diffusion mechanism. The final phase redistribution of oxygen ions in ReBa{sub 2}Cu{sub 3}O{sub 7−x} (Re = Y, Ho) is described by the classical mechanism of volume diffusion. The substitution of yttrium by holmium significantly affects the charge redistribution and changes the efficient interaction of ions in CuO-planes, thereby modifying the mass transfer diffusion mechanisms in the oxygen sublattice. Thus, a significant length change of the time intervals occurs, corresponding to the oxygen ions’ single file and volume diffusion mechanisms.

Preservation of refrigerated calf meat pieces by ionization

International Nuclear Information System (INIS)

Hassouna, M.; Besbes, M.; Ben Hassen, A.; Mahjoub, A.; Maalej, M.

1998-01-01

The influence of five 60Co gamma radiation doses in the range of 1 to 5 kGy on chemical composition and bacteriological counts of pieces of calf meat, partially vacuum - packed before treatment, was studied during storage at + 4 degree C up to 28 days. In vivo thermoluminescence dosimetry (TLD) using dosimeters such as lithium fluoride (LiF) was used as a very sensitive procedure to control both dose delivered to the red meat and its degree of uniformity. These two parameters are generally recommended for the quality control of food irradiation process. While ionizing radiation doses of 1 or 2 kGy were unable to increase the shelf life of treated meat, doses of 3, 4 or 5 kGy were very efficient, and adequate to prevent completely the growth of microorganisms indicating faecal contamination such as total coliforms, faecal coliforms and Enterobacteriaceae; they also kept constant the contents of total mesophilic flora and maintained radioresistant psychrotrophic microflora below the value inducing superficial putrefaction of meat (10 7 CFU cntdot g -1 ) at all storage times. Pathogenic germs producing contaminating toxins in foodstuffs such as Salmonella, Staphylococcus aureus and anaerobic sulfite reducing bacteria were totally absent in both control and treated meat. When pieces of meat were irradiated with doses of 3, 4 or 5 kGy, microbial alcalinization and proteolysis revealed by total volatile basic nitrogen were very low during the whole storage period. In addition, total protein did not change as a result of treatment during that period. However, superficial browning and significant variations were observed in water - holding capacity and saturated and unsaturated fatty acids contents in the free fat of treated meat. Ionizing radiation doses had no effect on weight losses and even on the variations of pH after heating of ground calf meat in double boiler at 50, 70 or 90 degree C up to 1 h. However, these modifications very sensitive to cooking temperature

Seeking Emancipation from Gender Regulation: Reflections on Home Space for a Black Woman Academic/Single Mother

Science.gov (United States)

William-­White, Lisa

2012-01-01

Using the work of Judith Butler on gender regulation, Black Feminist Thought (BFT), and autobiographic storytelling, this piece illustrates how essentialist notions of gender, and discourses related to gender create conflict in shaping identity construction for a Black woman academic and single mother (BWA/SM) in the United States. This piece…

From Sound to Significance: Exploring the Mechanisms Underlying Emotional Reactions to Music.

Science.gov (United States)

Juslin, Patrik N; Barradas, Gonçalo; Eerola, Tuomas

2015-01-01

A common approach to studying emotional reactions to music is to attempt to obtain direct links between musical surface features such as tempo and a listener's responses. However, such an analysis ultimately fails to explain why emotions are aroused in the listener. In this article we explore an alternative approach, which aims to account for musical emotions in terms of a set of psychological mechanisms that are activated by different types of information in a musical event. This approach was tested in 4 experiments that manipulated 4 mechanisms (brain stem reflex, contagion, episodic memory, musical expectancy) by selecting existing musical pieces that featured information relevant for each mechanism. The excerpts were played to 60 listeners, who were asked to rate their felt emotions on 15 scales. Skin conductance levels and facial expressions were measured, and listeners reported subjective impressions of relevance to specific mechanisms. Results indicated that the target mechanism conditions evoked emotions largely as predicted by a multimechanism framework and that mostly similar effects occurred across the experiments that included different pieces of music. We conclude that a satisfactory account of musical emotions requires consideration of how musical features and responses are mediated by a range of underlying mechanisms.

Mechanical Revascularization for Acute Ischemic Stroke: A Single-Center, Retrospective Analysis

International Nuclear Information System (INIS)

Jeromel, Miran; Milosevic, Z. V.; Kocijancic, I. J.; Lovric, D.; Svigelj, V.; Zvan, B.

2013-01-01

BackgroundEndovascular mechanical revascularization (thrombectomy) is an increasingly used method for intracranial large vessel recanalization in acute stroke. The purpose of the study was to analyze the recanalization rate, clinical outcome, and complication rate in our stroke patients treated with mechanical revascularization. A total of 57 patients with large vessel stroke (within 3 h for anterior and 12 h for posterior circulation) were treated with mechanical revascularization at a single center during 24 months. The primary goal of endovascular treatment using different mechanical devices was recanalization of the occluded vessel. Recanalization rate (reported as thrombolysis in cerebral infarction [TICI] score), clinical outcome (reported as National Institutes of Health Stroke Scale [NIHSS] score and modified Rankin scale [mRS] score), as well as periprocedural complications were analyzed. The mean age of the patients was 63.1 ± 12.9 years, with baseline median NIHSS score of 14 (interquartile range, 9.5–19). Successful recanalization (TICI 2b or 3) was achieved in 41 (72 %) patients. Twenty patients (35 %) presented with favorable outcome (mRS ≤2) 30 days after stroke. Overall, significant neurological improvement (≥4 NIHSS point reduction) occurred in 36 (63 %) patients. A clinically significant procedure-related adverse events (vessel disruption, peri/postprocedural intracranial bleeding) defined with decline in NIHSS of ≥4 or death occurred in three (5 %) patients. The study showed a high recanalization rate with improved clinical outcome and a low rate of periprocedural complications in our stroke patients treated with mechanical revascularization. Therefore, we could conclude that endovascular revascularization (primary or in combination with a bridging thrombolysis) was an effective and safe procedure for intracranial large vessel recanalization in acute stroke.

A comparative study of microstructure and mechanical properties between friction stir welded single and double phase brass alloys

International Nuclear Information System (INIS)

Heidarzadeh, A.; Saeid, T.

2016-01-01

This study was done in order to compare the microstructure and mechanical properties of friction stir welded single and double phase brass alloys. The microstructure of the joints were examined using optical microscope, scanning electron microscope (SEM), scanning transmission electron microscope (STEM), and X-ray diffraction. Furthermore, tensile test and fractography were applied to evaluate the mechanical properties of the joints. The results showed that the grain size of the stir zone in the double phase joint was smaller than that of the single phase alloy. In comparison with base metals, both of the joints contained high density of dislocations with a qualitatively similar texture. However, the dislocation density of the double phase joint was somewhat lower than that of the single phase one. Moreover, the joints had higher tensile strength, lower elongation and less ductile fracture compared to their base metals due to their finer grain size and higher dislocation density. The double phase joint had higher strength and lower elongation than single phase joint due to the effect of the second phase.

Dramatherapy and Family Therapy in Education: Essential Pieces of the Multi-Agency Jigsaw

Science.gov (United States)

McFarlane, Penny; Harvey, Jenny

2012-01-01

A collaborative therapeutic approach often proves the best way to assess and meet the needs of children experiencing barriers to learning. This book gives a concise overview of drama and family therapy and describes how both therapies can work together to provide essential pieces of the jigsaw of emotional support for troubled children within an…

Research on Design and Simulation of Biaxial Tensile-Bending Complex Mechanical Performance Test Apparatus

Directory of Open Access Journals (Sweden)

Hailian Li

2017-09-01

Full Text Available In order to realize a micro-mechanic performance test of biaxial tensile-bending-combined loading and solve the problem of incompatibility of test apparatus and observation apparatus, novel biaxial-combined tensile-bending micro-mechanical performance test apparatus was designed. The working principle and major functions of key constituent parts of test apparatus, including the servo drive unit, clamping unit and test system, were introduced. Based on the finite element method, biaxial tensile and tension-bending-combined mechanical performances of the test-piece were studied as guidance to learn the distribution of elastic deformation and plastic deformation of all sites of the test-piece and to better plan test regions. Finally, this test apparatus was used to conduct a biaxial tensile test under different pre-bending loading and a tensile test at different rates; the image of the fracture of the test-piece was acquired by a scanning electron microscope and analyzed. It was indicated that as the pre-bending force rises, the elastic deformation phase would gradually shorten and the slope of the elastic deformation phase curve would slightly rise so that a yield limit would appear ahead of time. Bending speed could exert a positive and beneficial influence on tensile strength but weaken fracture elongation. If bending speed is appropriately raised, more ideal anti-tensile strength could be obtained, but fracture elongation would decline.

Effect of waste synthetic bag pieces on the CBR value of expansive Soil

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Ajay Kumar Agarwal

2015-03-01

Full Text Available Expansive soils such as black cotton soil which are widely distributed in India have a tendency for volume changes due to change in moisture content. Also exhibits very low bearing capacity and high compressibility. Stabilization of such soil by admixture is used commonly now days. But no mix is suitable to improve all the types of soil. But it is obvious that depending on type of soil & type of admixture the optimum mix can be designed.  In this paper a mix has been designed to improve the bearing capacity of soil by using fly ash and lime mixture, reinforced with waste synthetic bag pieces. Various tests are carried out to determine the CBR value and other soil properties with and without using any admixture and reinforcement. The maximum value of CBR was found to be23.82% for 2.5 mm penetration and 22.21% for 5 mm penetration, when waste synthetic bag pieces of size 2 cm * 2 cm were used at a proportion of 0.1%.

Nanoscale mechanical surface properties of single crystalline martensitic Ni-Mn-Ga ferromagnetic shape memory alloys

International Nuclear Information System (INIS)

Jakob, A M; Müller, M; Rauschenbach, B; Mayr, S G

2012-01-01

Located beyond the resolution limit of nanoindentation, contact resonance atomic force microscopy (CR-AFM) is employed for nano-mechanical surface characterization of single crystalline 14M modulated martensitic Ni-Mn-Ga (NMG) thin films grown by magnetron sputter deposition on (001) MgO substrates. Comparing experimental indentation moduli-obtained with CR-AFM-with theoretical predictions based on density functional theory (DFT) indicates the central role of pseudo plasticity and inter-martensitic phase transitions. Spatially highly resolved mechanical imaging enables the visualization of twin boundaries and allows for the assessment of their impact on mechanical behavior at the nanoscale. The CR-AFM technique is also briefly reviewed. Its advantages and drawbacks are carefully addressed. (paper)

An Engineered Kinetic Amplification Mechanism for Single Nucleotide Variant Discrimination by DNA Hybridization Probes.

Science.gov (United States)

Chen, Sherry Xi; Seelig, Georg

2016-04-20

Even a single-nucleotide difference between the sequences of two otherwise identical biological nucleic acids can have dramatic functional consequences. Here, we use model-guided reaction pathway engineering to quantitatively improve the performance of selective hybridization probes in recognizing single nucleotide variants (SNVs). Specifically, we build a detection system that combines discrimination by competition with DNA strand displacement-based catalytic amplification. We show, both mathematically and experimentally, that the single nucleotide selectivity of such a system in binding to single-stranded DNA and RNA is quadratically better than discrimination due to competitive hybridization alone. As an additional benefit the integrated circuit inherits the property of amplification and provides at least 10-fold better sensitivity than standard hybridization probes. Moreover, we demonstrate how the detection mechanism can be tuned such that the detection reaction is agnostic to the position of the SNV within the target sequence. in contrast, prior strand displacement-based probes designed for kinetic discrimination are highly sensitive to position effects. We apply our system to reliably discriminate between different members of the let-7 microRNA family that differ in only a single base position. Our results demonstrate the power of systematic reaction network design to quantitatively improve biotechnology.

Mechanically Reconfigurable Single-Arm Spiral Antenna Array for Generation of Broadband Circularly Polarized Orbital Angular Momentum Vortex Waves.

Science.gov (United States)

Li, Long; Zhou, Xiaoxiao

2018-03-23

In this paper, a mechanically reconfigurable circular array with single-arm spiral antennas (SASAs) is designed, fabricated, and experimentally demonstrated to generate broadband circularly polarized orbital angular momentum (OAM) vortex waves in radio frequency domain. With the symmetrical and broadband properties of single-arm spiral antennas, the vortex waves with different OAM modes can be mechanically reconfigurable generated in a wide band from 3.4 GHz to 4.7 GHz. The prototype of the circular array is proposed, conducted, and fabricated to validate the theoretical analysis. The simulated and experimental results verify that different OAM modes can be effectively generated by rotating the spiral arms of single-arm spiral antennas with corresponding degrees, which greatly simplify the feeding network. The proposed method paves a reconfigurable way to generate multiple OAM vortex waves with spin angular momentum (SAM) in radio and microwave satellite communication applications.

Modified section method for laser-welding of ill-fitting cp Ti and Ni-Cr alloy one-piece cast implant-supported frameworks.

Science.gov (United States)

Tiossi, R; Falcão-Filho, H; Aguiar Júnior, F A; Rodrigues, R C; Mattos, M da G; Ribeiro, R F

2010-05-01

This study aimed to verify the effect of modified section method and laser-welding on the accuracy of fit of ill-fitting commercially pure titanium (cp Ti) and Ni-Cr alloy one-piece cast frameworks. Two sets of similar implant-supported frameworks were constructed. Both groups of six 3-unit implant-supported fixed partial dentures were cast as one-piece [I: Ni-Cr (control) and II: cp Ti] and evaluated for passive fitting in an optical microscope with both screws tightened and with only one screw tightened. All frameworks were then sectioned in the diagonal axis at the pontic region (III: Ni-Cr and IV: cp Ti). Sectioned frameworks were positioned in the matrix (10-Ncm torque) and laser-welded. Passive fitting was evaluated for the second time. Data were submitted to anova and Tukey-Kramer honestly significant difference tests (P screws tightened, one-piece cp Ti group II showed significantly higher misfit values (27.57 +/- 5.06 microm) than other groups (I: 11.19 +/- 2.54 microm, III: 12.88 +/- 2.93 microm, IV: 13.77 +/- 1.51 microm) (P screw-tightened test, with readings on the opposite side to the tightened side, Ni-Cr cast as one-piece (I: 58.66 +/- 14.30 microm) was significantly different from cp Ti group after diagonal section (IV: 27.51 +/- 8.28 microm) (P 0.05). Results showed that diagonally sectioning ill-fitting cp Ti frameworks lowers misfit levels of prosthetic implant-supported frameworks and also improves passivity levels of the same frameworks when compared to one-piece cast structures.

Opto-acoustic microscopy reveals adhesion mechanics of single cells

Science.gov (United States)

Abi Ghanem, Maroun; Dehoux, Thomas; Liu, Liwang; Le Saux, Guillaume; Plawinski, Laurent; Durrieu, Marie-Christine; Audoin, Bertrand

2018-01-01

Laser-generated GHz-ultrasonic-based technologies have shown the ability to image single cell adhesion and stiffness simultaneously. Using this new modality, we here demonstrate quantitative indicators to investigate contact mechanics and adhesion processes of the cell. We cultured human cells on a rigid substrate, and we used an inverted pulsed opto-acoustic microscope to generate acoustic pulses containing frequencies up to 100 GHz in the substrate. We map the reflection of the acoustic pulses at the cell-substrate interface to obtain images of the acoustic impedance of the cell, Zc, as well as of the stiffness of the interface, K, with 1 μm lateral resolution. Our results show that the standard deviation ΔZc reveals differences between different cell types arising from the multiplicity of local conformations within the nucleus. From the distribution of K-values within the nuclear region, we extract a mean interfacial stiffness, Km, that quantifies the average contact force in areas of the cell displaying weak bonding. By analogy with classical contact mechanics, we also define the ratio of the real to nominal contact areas, Sr/St. We show that Km can be interpreted as a quantitative indicator of passive contact at metal-cell interfaces, while Sr/St is sensitive to active adhesive processes in the nuclear region. The ability to separate the contributions of passive and active adhesion processes should allow gaining insight into cell-substrate interactions, with important applications in tissue engineering.

Waterbomb base: a symmetric single-vertex bistable origami mechanism

International Nuclear Information System (INIS)

Hanna, Brandon H; Lund, Jason M; Magleby, Spencer P; Howell, Larry L; Lang, Robert J

2014-01-01

The origami waterbomb base is a single-vertex bistable origami mechanism that has unique properties which may prove useful in a variety of applications. It also shows promise as a test bed for smart materials and actuation because of its straightforward geometry and multiple phases of motion, ranging from simple to more complex. This study develops a quantitative understanding of the symmetric waterbomb base's kinetic behavior. This is done by completing kinematic and potential energy analyses to understand and predict bistable behavior. A physical prototype is constructed and tested to validate the results of the analyses. Finite element and virtual work analyses based on the prototype are used to explore the locations of the stable equilibrium positions and the force–deflection response. The model results are verified through comparisons to measurements on a physical prototype. The resulting models describe waterbomb base behavior and provide an engineering tool for application development. (paper)

Single-step brazing process for mono-block joints and mechanical testing

Energy Technology Data Exchange (ETDEWEB)

Casalegno, V.; Ferraris, M.; Salvo, M.; Rizzo, S. [Politecnico di Torino, Materials Science and Chemical Engineering Dept., Torino (Italy); Merola, M. [ITER International Team, llER Joint Work Site, Cadarache, 13 - St Paul Lez Durance (France)

2007-07-01

Full text of publication follows: Plasma facing components act as actively cooled thermal shields to sustain thermal and particle loads during normal and transient operations in ITER (International Thermonuclear Experimental Reactor). The plasma-facing layer is referred to as 'armour', which is made of either carbon fibre reinforced carbon composite (CFC) or tungsten (W). CFC is the reference design solution for the lower part of the vertical target of the ITER divertor. The armour is joined onto an actively cooled substrate, the heat sink, made of precipitation hardened copper alloy CuCrZr through a thin pure copper interlayer to decrease, by plastic deformation, the joint interface stresses; in fact, the CFC to Cu joint is affected by the CTE mismatch between the ceramic and metallic material. A new method of joining CFC to copper and CFC/Cu to CuCrZr alloy was effectively developed for the flat-type configuration; the feasibility of this process also for mono-block geometry and the development of a procedure for testing mono-block-type mock-ups is described in this work. The mono-block configuration consists of copper alloy pipe shielded by CFC blocks. It is worth noting that in mono-block configuration, the large thermal expansion mismatch between CFC and copper alloy is more significant than for flat-tile configuration, due to curved interfaces. The joining technique foresees a single-step brazing process: the brazing of the three materials (CFC-Cu-CuCrZr) can be performed in a single heat treatment using the same Cu/Ge based braze. The composite surface was modified by solid state reaction with chromium with the purpose of increasing the wettability of CFC by the brazing alloy. The CFC substrate reacts with Cr which, forming a carbide layer, allows a large reduction of the contact angle; then, the brazing of CFC to pure copper and pure copper to CuCrZr by the same treatment is feasible. This process allows to obtain good joints using a non

Single-step brazing process for mono-block joints and mechanical testing

International Nuclear Information System (INIS)

Casalegno, V.; Ferraris, M.; Salvo, M.; Rizzo, S.; Merola, M.

2007-01-01

Full text of publication follows: Plasma facing components act as actively cooled thermal shields to sustain thermal and particle loads during normal and transient operations in ITER (International Thermonuclear Experimental Reactor). The plasma-facing layer is referred to as 'armour', which is made of either carbon fibre reinforced carbon composite (CFC) or tungsten (W). CFC is the reference design solution for the lower part of the vertical target of the ITER divertor. The armour is joined onto an actively cooled substrate, the heat sink, made of precipitation hardened copper alloy CuCrZr through a thin pure copper interlayer to decrease, by plastic deformation, the joint interface stresses; in fact, the CFC to Cu joint is affected by the CTE mismatch between the ceramic and metallic material. A new method of joining CFC to copper and CFC/Cu to CuCrZr alloy was effectively developed for the flat-type configuration; the feasibility of this process also for mono-block geometry and the development of a procedure for testing mono-block-type mock-ups is described in this work. The mono-block configuration consists of copper alloy pipe shielded by CFC blocks. It is worth noting that in mono-block configuration, the large thermal expansion mismatch between CFC and copper alloy is more significant than for flat-tile configuration, due to curved interfaces. The joining technique foresees a single-step brazing process: the brazing of the three materials (CFC-Cu-CuCrZr) can be performed in a single heat treatment using the same Cu/Ge based braze. The composite surface was modified by solid state reaction with chromium with the purpose of increasing the wettability of CFC by the brazing alloy. The CFC substrate reacts with Cr which, forming a carbide layer, allows a large reduction of the contact angle; then, the brazing of CFC to pure copper and pure copper to CuCrZr by the same treatment is feasible. This process allows to obtain good joints using a non-active brazing

[Newborn ventilation: comparison between a T-piece resuscitator and self-infating bags in a neonatal preterm simulator].

Science.gov (United States)

Szyld, Edgardo G; Aguilar, Adriana M; Musante, Gabriel A; Vain, Néstor E; Guerrero, Miriam N; Serra, María Elina; Prudent, Luis M; Carlo, Waldemar A

2012-04-01

Although the provision of effective assisted ventilation is the most effective intervention in delivery room resuscitation of depressed newborn infants, there is still limited evidence about which is the optimal device to deliver positive pressure ventilation (PPV). To compare the accuracy of pressures and ventilation rate (VR) delivered to a neonatal simulator with three devices: 240 ml and 450 ml self-infating bags (SIB) and a T-piece resuscitator, and to evaluate the variability in terms of providers' experience. 76 health care providers divided in two groups according to experience were asked to provide positive pressure ventilation to a neonatal simulator through a facial mask or an endotracheal tube with three ventilating devices: a T-piece resuscitator, a 240 ml and a 450 ml self-infating bags. Participants used each combination of device and interface randomly on 2 consecutive occasions. Mean and maximum PIP and respiratory rate were recorded. Statistical analyses were performed using two-factor analysis of variance for repeated measures. SIB 240 and 450 were similar in the mean target peak inspiratory pressure (PIP) but both were significantly different (p values were close to the target. Mean VR was over the target for all the devices (p bag when compared with the T-piece using a mask. Experienced operators were closer than novice operators to target VR, regardless of the device or interface. The accuracy for the devices was comparable in the variables measured regardless operator´s experience. Overall, the T-piece provided lower PIP while both SIB, higher than the target. The VR was over the target for all the devices. Both SIB and novice participants were associated with higher VR. The intraoperator consistency was comparable in the variables measured with all devices.

Design and analysis of the Collider SPXA/SPRA spool piece vacuum barrier

International Nuclear Information System (INIS)

Cruse, G.; Aksel, G.

1993-04-01

A design for the Collider SPXA/SPRA spool piece vacuum barrier was developed to meet a variety of thermal and structural performance requirements. Both composite and stainless steel alternatives were investigated using detailed finite-element analysis before selecting an optimized version of the ASST SPR spool vacuum barrier design. This design meets the structural requirements and will be able to meet the thermal performance requirements by using some newer thermal strapping configurations

Effect of two-step aging on spatial distribution of γ-phase particles and mechanical properties of Ni-14at.% Al single crystals

International Nuclear Information System (INIS)

Tyapkin, Yu.D.; Travina, N.T.; Ugarova, E.V.

1977-01-01

Electron microscope images were processed by statistical methods to investigate the space distribution of particles of the γ'-phase (formation of ''quasiperiodic micro-lattices'') after various conditions of single- and double-stage aging of the Ni-14 at.% Al alloy. Mechanical properties in uniaxial tension of single crystals were studied. Parameters of the space distribution of particles have been correlated with the mechanical properties

Protein logic: a statistical mechanical study of signal integration at the single-molecule level.

Science.gov (United States)

de Ronde, Wiet; Rein ten Wolde, Pieter; Mugler, Andrew

2012-09-05

Information processing and decision-making is based upon logic operations, which in cellular networks has been well characterized at the level of transcription. In recent years, however, both experimentalists and theorists have begun to appreciate that cellular decision-making can also be performed at the level of a single protein, giving rise to the notion of protein logic. Here we systematically explore protein logic using a well-known statistical mechanical model. As an example system, we focus on receptors that bind either one or two ligands, and their associated dimers. Notably, we find that a single heterodimer can realize any of the 16 possible logic gates, including the XOR gate, by variation of biochemical parameters. We then introduce what to our knowledge is a novel idea: that a set of receptors with fixed parameters can encode functionally unique logic gates simply by forming different dimeric combinations. An exhaustive search reveals that the simplest set of receptors (two single-ligand receptors and one double-ligand receptor) can realize several different groups of three unique gates, a result for which the parametric analysis of single receptors and dimers provides a clear interpretation. Both results underscore the surprising functional freedom readily available to cells at the single-protein level. Copyright © 2012 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Single molecule dynamics at a mechanically controllable break junction in solution at room temperature.

Science.gov (United States)

Konishi, Tatsuya; Kiguchi, Manabu; Takase, Mai; Nagasawa, Fumika; Nabika, Hideki; Ikeda, Katsuyoshi; Uosaki, Kohei; Ueno, Kosei; Misawa, Hiroaki; Murakoshi, Kei

2013-01-23

The in situ observation of geometrical and electronic structural dynamics of a single molecule junction is critically important in order to further progress in molecular electronics. Observations of single molecular junctions are difficult, however, because of sensitivity limits. Here, we report surface-enhanced Raman scattering (SERS) of a single 4,4'-bipyridine molecule under conditions of in situ current flow in a nanogap, by using nano-fabricated, mechanically controllable break junction (MCBJ) electrodes. When adsorbed at room temperature on metal nanoelectrodes in solution to form a single molecule junction, statistical analysis showed that nontotally symmetric b(1) and b(2) modes of 4,4'-bipyridine were strongly enhanced relative to observations of the same modes in solid or aqueous solutions. Significant changes in SERS intensity, energy (wavenumber), and selectivity of Raman vibrational bands that are coincident with current fluctuations provide information on distinct states of electronic and geometrical structure of the single molecule junction, even under large thermal fluctuations occurring at room temperature. We observed the dynamics of 4,4'-bipyridine motion between vertical and tilting configurations in the Au nanogap via b(1) and b(2) mode switching. A slight increase in the tilting angle of the molecule was also observed by noting the increase in the energies of Raman modes and the decrease in conductance of the molecular junction.

Fitting the Pattern or being a dressmaker’s daughter: a memoir in pieces - Being Creatively Autobiographical in New Media

Directory of Open Access Journals (Sweden)

Christine Wilks

2009-07-01

Full Text Available Cutting through memories, pinning down facts, stitching up fabrications, unpicking the past - an interactive, animated memoir, created in Flash, exploring aspects of my relationship with my dressmaking mother and her complicated influence on me. Life’s mysteries are rarely uncovered by a logical, linear process of deduction. You arrive at answers, ideas, suspicions, intuitions… haphazardly in fragments. Over time you build the picture, piece by piece, shuffling and rearranging, until you start to see a pattern emerging. The structure of ‘Fitting the Pattern’ attempts to replicate this experience, hence it is a memoir in pieces that the reader can explore, to some extent, in a non-linear fashion. The visual design of the piece is based on the aesthetics of dressmaking patterns, specifically, imagery drawn from online open source sewing patterns (burdastyle.com. An affordance of such a design is that dressmaking patterns are instructional by nature so I was able to design an intuitive navigational system that provides signals and guidance to the user without breaking out of the narrative sphere and disrupting a potentially immersive experience. There are certain parallels between my motherʼs creative craft process and my own in new media. These similarities, as well as our differences, are embedded in the digital media and text, literally drawn out through animation and dramatised through interactivity. Custom cursors designed as digital dressmaking tools fuse the interactive process into the narrative world, so the reader becomes actively involved in constructing and/or unpicking the narrative. Like most of the interactive elements in ʻFitting the Patternʼ, these dressmaking tool symbols have multiple functions - they are navigation bar buttons; they are custom cursors; and they are active narrative elements, like animated characters, literally playing their part in the story whilst simultaneously activating the reading

Single and competitive adsorption of OMPs by carbon nanotubes - mechanism and fitting models

Science.gov (United States)

Kamińska, Gabriela; Dudziak, Mariusz; Bohdziewicz, Jolanta; Kudlek, Edyta

2017-11-01

The adsorption of three organic micropollutants (diclofenac - DFN, pentachlorophenol - PCP and octylphenol - OP) on two kinds of carbon nanotubes (single walled carbon nanotubes - SWCNT and single walled carbon nanotubes with amine group - SWCNT-NH2) was investigated, in single and bicomponent solution at pH 5. SWCNT-NH2 had three times lower specific surface area than SWCNT. Significant differences were observed in sorption capacity of SWCNT and SWCNT-NH2 for given chemicals. The sorption uptake changes in the following order: OP > PCP > DFN for SWCNT and DFN > PCP > OP for SWCNT-NH2. A few times higher adsorption of OP on SWCNT came from low OP solubility in water in comparison to PCP and DFN. While, higher adsorption of DFN and PCP on SWCNT-NH2 was a result of electrostatic attraction between dissociated form of these chemicals and positively charged SWCNT-NH2 at pH 5. In adsorption from bicomponent solution, significant competition was observed between PCP and DFN due to similar adsorption mechanism on SWCNT-NH2. Opposite tendency was observed for SWCNT, DFN did not greatly affect adsorption of PCP and OP since they were very easily absorbable by sigma-sigma interaction.

The Single Supervisory Mechanism: the Building Pillar of the European Banking Union

Directory of Open Access Journals (Sweden)

Luigi Chiarella

2016-07-01

Full Text Available One of the lessons learned from the 2008 financial crisis is that when a bank in Europe goes into trouble the ensuing effects can reach far beyond the immediate threat to its depositors and shareholders. In particular, the crisis has revealed the extent to which irresponsible behavior in the banking sector could undermine the foundations of the financial system and threaten the real economy, turning a banking crisis into a sovereign debt crisis as occurred in the eurozone in 2011. In response to this lesson, Member States first tried to address the systemic fragility of their banking systems through national policy tools, but countries that share a common currency and are more interdependent required more integrated responses. Therefore, at the euro area summit in June 2012, the European Council agreed to break the vicious circle between banks and sovereign debt and decided to create a banking union that would allow a centralized supervision for banks in the euro area through a newly established Single Supervisory Mechanism (SSM and a centralized resolution scheme. The SSM became operational in November 2014 and represents the building pillar of the banking union. The purpose of this paper is then to provide, after a brief description of the background (Par. 1, an analysis of the Single Supervisory Mechanism, illustrating its functioning (Par. 2, then focusing on the position and the powers of the ECB within it (Par. 3 and finally pointing out some remarks on the potential weaknesses of the new regime (Par. 4.

Precision toxicology based on single cell sequencing: an evolving trend in toxicological evaluations and mechanism exploration.

Science.gov (United States)

Zhang, Boyang; Huang, Kunlun; Zhu, Liye; Luo, Yunbo; Xu, Wentao

2017-07-01

In this review, we introduce a new concept, precision toxicology: the mode of action of chemical- or drug-induced toxicity can be sensitively and specifically investigated by isolating a small group of cells or even a single cell with typical phenotype of interest followed by a single cell sequencing-based analysis. Precision toxicology can contribute to the better detection of subtle intracellular changes in response to exogenous substrates, and thus help researchers find solutions to control or relieve the toxicological effects that are serious threats to human health. We give examples for single cell isolation and recommend laser capture microdissection for in vivo studies and flow cytometric sorting for in vitro studies. In addition, we introduce the procedures for single cell sequencing and describe the expected application of these techniques to toxicological evaluations and mechanism exploration, which we believe will become a trend in toxicology.

Sand moulds milling for one-of-a-kind pieces

Science.gov (United States)

Rodríguez, A.; Calleja, A.; Olvera, D.; Peñafiel, F. J.; López de Lacalle, L. N.

2012-04-01

Time to market is a critical measurement for today's foundry market. Combining 3D digitizing and sand blocks milling is possible to reduce this time. Avoiding the use of a wood pattern, this technique is useful for art pieces or unique parts, when only one component is necessary. The key of the proposed methodology is to achieve enough tool life with conventional tool qualities, avoiding the risk of sand destruction or damage. A special study of tool wear is presented in this work, studying different tool materials and different sand types. Two examples of unique parts are also presented in this work following the proposed methodology in order to reduce time and cost for the rapid reproduction of very short batches.

Solar project description for Zien Mechanical Contractors-I single family residence, Milwaukee, Wisconsin

Science.gov (United States)

Beers, D.

1980-02-01

The Zien Mechanical site is a single family residence located in Milwaukee, Wisconsin. The home has two separate solar energy systems: an air system for space heating and cooling; a liquid system to preheat the potable hot water. The space heating and cooling system design and operation modes are described. The space heating system is designed to apply approximately 44 percent of the space heating requirements for the 1388 square foot residence. Engineering drawings are provided and the performance evaluation instrumentation is described.

Classification of archaeological pieces into their respective stratum by a chemometric model based on the soil concentration of 25 selected elements

International Nuclear Information System (INIS)

Carrero, J.A.; Goienaga, N.; Fdez-Ortiz de Vallejuelo, S.; Arana, G.; Madariaga, J.M.

2010-01-01

The aim of this work was to demonstrate that an archaeological ceramic piece has remained buried underground in the same stratum for centuries without being removed. For this purpose, a chemometric model based on Principal Component Analysis, Soft Independent Modelling of Class Analogy and Linear Discriminant Analysis classification techniques was created with the concentration of some selected elements of both soil of the stratum and soil adhered to the ceramic piece. Some ceramic pieces from four different stratigraphic units, coming from a roman archaeological site in Alava (North of Spain), and its respective stratum soils were collected. The soil adhered to the ceramic pieces was removed and treated in the same way as the soil from its respective stratum. The digestion was carried out following the US Environmental Pollution Agency EPA 3051A method. A total of 54 elements were determined in the extracts by a rapid screening inductively coupled plasma mass spectrometry method. After rejecting the major elements and those which could have changed from the original composition of the soils (migration or retention from/to the buried objects), the following elements (25) were finally taken into account to construct the model: Li, V, Co, As, Y, Nb, Sn, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Au, Th and U. A total of 33 subsamples were treated from 10 soils belonging to 4 different stratigraphic units. The final model groups and discriminate them in four groups, according to the stratigraphic unit, having both the stratum and soils adhered to the pieces falling down in the same group.

Use of large pieces of printed circuit boards for bioleaching to avoid 'precipitate contamination problem' and to simplify overall metal recovery.

Science.gov (United States)

Adhapure, N N; Dhakephalkar, P K; Dhakephalkar, A P; Tembhurkar, V R; Rajgure, A V; Deshmukh, A M

2014-01-01

Very recently bioleaching has been used for removing metals from electronic waste. Most of the research has been targeted to using pulverized PCBs for bioleaching where precipitate formed during bioleaching contaminates the pulverized PCB sample and making the overall metal recovery process more complicated. In addition to that, such mixing of pulverized sample with precipitate also creates problems for the final separation of non metallic fraction of PCB sample. In the present investigation we attempted the use of large pieces of printed circuit boards instead of pulverized sample for removal of metals. Use of large pieces of PCBs for bioleaching was restricted due to the chemical coating present on PCBs, the problem has been solved by chemical treatment of PCBs prior to bioleaching. In short,•Large pieces of PCB can be used for bioleaching instead of pulverized PCB sample.•Metallic portion on PCBs can be made accessible to bacteria with prior chemical treatment of PCBs.•Complete metal removal obtained on PCB pieces of size 4 cm × 2.5 cm with the exception of solder traces. The final metal free PCBs (non metallic) can be easily recycled and in this way the overall recycling process (metallic and non metallic part) of PCBs becomes simple.

Thermal-mechanical-hydrological-chemical responses in the single heater test at the ESF

International Nuclear Information System (INIS)

Lin, W.; Blair, S.; Buettner, M

1997-01-01

The Single Heater Test (SHT) is conducted in the Exploratory Studies Facility (ESF) to study the thermal-mechanical responses of the rock mass. A set of boreholes were drilled in the test region for conducting a scoping test of the coupled thermal-mechanical- hydrological-chemical (TMHC) processes. The holes for the TMHC tests include electrical resistivity tomography (ERT), neutron logging/temperature, hydrological, and optical multiple point borehole extensometers. A 4-kW heater was installed in the heater hole, and was energized on August 26, 1996. Some observed movements of the water around the heater are associated with a possible dry-out region near the heater. The water that has been moved is more dilute than the in situ ground water, except for the concentration of Ca. This indicates that fractures are the major water pathways, and the displaced water may have reached an equilibrium with carbonate minerals on the fracture surfaces. No mechanical-hydrological coupling has been observed. The tests are on-going, and more data will be collected and analyzed

Telecommunications and internet broadband policy: sorting out the pieces for telerehabilitation.

Science.gov (United States)

Seelman, Katherine D

2010-01-01

Technological change is accelerating and with it regulatory upheaval. Most of us agree that providing universal telecommunication services to all our citizens is a worthy ideal. Nonetheless, many of us do not agree that regulation should be the means to make broadband Internet services widely available. This Viewpoint begins sorting out pieces of the emerging United States, regulatory and policy puzzle for broadband Internet with an eye to the interests of telerehabilitation providers and consumers. Just how might changes in legal authority, regulation and agency jurisdictions impact us?

Comparison of training in neonatal resuscitation using self inflating bag and T-piece resuscitator

Science.gov (United States)

Mathai, S.S.; Adhikari, K.M.; Rajeev, A.

2014-01-01

Background Both the self inflating bag and the T-piece resuscitator are recommended for neonatal resuscitation, but many health care workers are unfamiliar with using the latter. A prospective, comparative, observational study was done to determine the ease and effectiveness of training of health care personnel in the two devices using infant training manikins. Methods 100 health care workers, who had no prior formal training in neonatal resuscitation, were divided into small groups and trained in the use of the two devices by qualified trainers. Assessment of cognitive skills was done by pre and post MCQs. Psychomotor skill was assessed post training on manikins using a 10-point objective score. Acceptance by users was ascertained by questionnaire. Assessments were also done after 24 h and 3 months. Comparison was done by Chi square and paired t-tests. Results Pre-training cognitive tests increased from 3.77 (+1.58) to 6.99 (+1.28) on day of training which was significant. Post training assessment of psychomotor skills showed significantly higher initial scores for the T-piece group (7.07 + 2.57) on day of training. Reassessment after 24 h showed significant improvement in cognitive scores (9.89 + 1.24) and psychomotor scores in both groups (8.86 + 1.42 for self inflating bag and 9.70 + 0.57 for T-piece resuscitator). After 3–6 months the scores in both domains showed some decline which was not statistically significant. User acceptability was the same for both devices. Conclusion It is equally easy to train health care workers in both devices. Both groups showed good short term recall and both devices were equally acceptable to the users. PMID:25609858

Opto-acoustic microscopy reveals adhesion mechanics of single cells.

Science.gov (United States)

Abi Ghanem, Maroun; Dehoux, Thomas; Liu, Liwang; Le Saux, Guillaume; Plawinski, Laurent; Durrieu, Marie-Christine; Audoin, Bertrand

2018-01-01

Laser-generated GHz-ultrasonic-based technologies have shown the ability to image single cell adhesion and stiffness simultaneously. Using this new modality, we here demonstrate quantitative indicators to investigate contact mechanics and adhesion processes of the cell. We cultured human cells on a rigid substrate, and we used an inverted pulsed opto-acoustic microscope to generate acoustic pulses containing frequencies up to 100 GHz in the substrate. We map the reflection of the acoustic pulses at the cell-substrate interface to obtain images of the acoustic impedance of the cell, Z c , as well as of the stiffness of the interface, K, with 1 μm lateral resolution. Our results show that the standard deviation ΔZ c reveals differences between different cell types arising from the multiplicity of local conformations within the nucleus. From the distribution of K-values within the nuclear region, we extract a mean interfacial stiffness, K m , that quantifies the average contact force in areas of the cell displaying weak bonding. By analogy with classical contact mechanics, we also define the ratio of the real to nominal contact areas, S r /S t . We show that K m can be interpreted as a quantitative indicator of passive contact at metal-cell interfaces, while S r /S t is sensitive to active adhesive processes in the nuclear region. The ability to separate the contributions of passive and active adhesion processes should allow gaining insight into cell-substrate interactions, with important applications in tissue engineering.

Dynamic mechanical analysis of single walled carbon nanotubes/polymethyl methacrylate nanocomposite films

International Nuclear Information System (INIS)

Badawi, Ali; Al Hosiny, N.

2015-01-01

Dynamic mechanical properties of nanocomposite films with different ratios of single walled carbon nanotubes/polymethyl methacrylate (SWCNTs/PMMA) are studied. Nanocomposite films of different ratios (0, 0.5, 1.0, and 2.0 weight percent (wt%)) of SWCNTs/PMMA are fabricated by using a casting technique. The morphological and structural properties of both SWCNT powder and SWCNTs/PMMA nanocomposite films are investigated by using a high resolution transmission electron microscope and x-ray diffractometer respectively. The mechanical properties including the storage modulus, loss modulus, loss factor (tan δ) and stiffness of the nanocomposite film as a function of temperature are recorded by using a dynamic mechanical analyzer at a frequency of 1 Hz. Compared with pure PMMA film, the nanocomposite films with different ratios of SWCNTs/PMMA are observed to have enhanced storage moduli, loss moduli and high stiffness, each of which is a function of temperature. The intensity of the tan δ peak for pure PMMA film is larger than those of the nanocomposite films. The glass transition temperature (T g ) of SWCNTs/PMMA nanocomposite film shifts towards the higher temperature side with respect to pure PMMA film from 91.2 °C to 99.5 °C as the ratio of SWCNTs/PMMA increases from 0 to 2.0 wt%. (paper)

Bacterial contamination of stethoscope chest pieces and the effect of daily cleaning.

Science.gov (United States)

Fujita, H; Hansen, B; Hanel, R

2013-01-01

Stethoscopes are a potential source of nosocomial infection for hospitalized humans, a phenomenon not previously studied in companion animals. To determine if daily cleaning of stethoscope chest pieces reduces bacterial contamination between cleanings. Client-owned dogs and cats. Prospective observational study. In phase 1, bacterial cultures were obtained from the chest pieces of 10 participant stethoscopes once weekly for 3 weeks. In phase 2, stethoscopes were cleaned daily and 2 culture samples were obtained once weekly, immediately before and after cleaning with 70% isopropyl alcohol, for 3 weeks. Daily cleaning eliminated bacteria immediately after each cleaning (P = .004), but did not reduce the rate of positive cultures obtained before cleaning in phase 2. Cultures were positive for 20/30 (67%) samples during phase 1 and 18/30 (60%) obtained before daily cleaning during phase 2. Recovered organisms included normal skin flora, agents of opportunistic infections, and potential pathogens. The only genus that was repeatedly recovered from the same stethoscope for 2 or more consecutive weeks was Bacillus sp. Daily cleaning was highly effective at removing bacteria, but provided no reduction in precleaning contamination. Cleaning stethoscopes after use on dogs or cats infected with pathogenic bacteria and before use on immunocompromised animals should be considered. Copyright © 2013 by the American College of Veterinary Internal Medicine.

Stability of prototype two-piece zirconia and titanium implants after artificial aging: an in vitro pilot study.

Science.gov (United States)

Kohal, Ralf-Joachim; Finke, Hans Christian; Klaus, Gerold

2009-12-01

Zirconia oral implants are a new topic in implant dentistry. So far, no data are available on the biomechanical behavior of two-piece zirconia implants. Therefore, the purpose of this pilot investigation was to test in vitro the fracture strength of two-piece cylindrical zirconia implants after aging in a chewing simulator. This laboratory in vitro investigation comprised three different treatment groups. Each group consisted of 16 specimens. In group 1, two-piece zirconia implants were restored with zirconia crowns (zirconia copings veneered with Triceram; Esprident, Ispringen, Germany), and in group 2 zirconia implants received Empress 2 single crowns (Ivoclar Vivadent AG, Schaan, Liechtenstein). The implants, including the abutments, in the two zirconia groups were identical. In group 3, similar titanium implants were reconstructed with porcelain-fused-to-metal crowns. Eight samples of each group were submitted to artificial aging with a long-term load test in the artificial mouth (chewing simulator). Subsequently, all not artificially aged samples and all artificially aged samples that survived the long-term loading of each group were submitted to a fracture strength test in a universal testing machine. For the pairwise comparisons in the different test groups with or without artificial loading and between the different groups at a given artificial loading condition, the Wilcoxon rank-sum test for independent samples was used. The significance level was set at 5%. One sample of group 1 (veneer fracture), none of group 2, and six samples of group 3 (implant abutment screw fractures) failed while exposed to the artificial mouth. The values for the fracture strength after artificial loading with 1.2 million cycles for group 1 were between 45 and 377 N (mean: 275.7 N), in group 2 between 240 and 314 N (mean: 280.7 N), and in the titanium group between 45 and 582 N (mean: 165.7 N). The fracture strength results without artificial load for group 1 amounted to between

Resolving the Aerosol Piece of the Global Climate Picture

Science.gov (United States)

Kahn, R. A.

2017-12-01

Factors affecting our ability to calculate climate forcing and estimate model predictive skill include direct radiative effects of aerosols and their indirect effects on clouds. Several decades of Earth-observing satellite observations have produced a global aerosol column-amount (AOD) record, but an aerosol microphysical property record required for climate and many air quality applications is lacking. Surface-based photometers offer qualitative aerosol-type classification, and several space-based instruments map aerosol air-mass types under favorable conditions. However, aerosol hygroscopicity, mass extinction efficiency (MEE), and quantitative light absorption, must be obtained from in situ measurements. Completing the aerosol piece of the climate picture requires three elements: (1) continuing global AOD and qualitative type mapping from space-based, multi-angle imagers and aerosol vertical distribution from near-source stereo imaging and downwind lidar, (2) systematic, quantitative in situ observations of particle properties unobtainable from space, and (3) continuing transport modeling to connect observations to sources, and extrapolate limited sampling in space and time. At present, the biggest challenges to producing the needed aerosol data record are: filling gaps in particle property observations, maintaining global observing capabilities, and putting the pieces together. Obtaining the PDFs of key particle properties, adequately sampled, is now the leading observational deficiency. One simplifying factor is that, for a given aerosol source and season, aerosol amounts often vary, but particle properties tend to be repeatable. SAM-CAAM (Systematic Aircraft Measurements to Characterize Aerosol Air Masses), a modest aircraft payload deployed frequently could fill this gap, adding value to the entire satellite data record, improving aerosol property assumptions in retrieval algorithms, and providing MEEs to translate between remote-sensing optical constraints

Mechanisms of tryptophan adsorption onto single-walled carbon nanotubes

International Nuclear Information System (INIS)

Zhou Jieping; Tan Jun; Xu Pengshou; Sheng Liusi; Pan Guoqiang

2011-01-01

Near edge X-ray absorption fine structure spectroscopy (NEXAFS) and synchrotron radiation photoelectron spectroscopy (SRPES) were employed to investigate the adsorption mechanism of tryptophan (Trp) onto single-walled carbon nanotubes (SWCNTs). The difference of the carbon K-edge NEXAFS spectra between Trp molecules and Trp-adsorbed SWCNTs shows that a significant interaction occurs among the SWCNTs and Trp molecules adsorbed. However, negligible changes in the peak profiles and energy positions of nitrogen K-edge imply that neither of the two nitrogen atoms in Trp molecule is involved in the interface interaction. A change of the shape of the main absorption peak at the oxygen K-edge reveals that O atoms of the C=O or C-O or both are likely involved in the interface interaction. The fact that the peak at about 529 eV at the O K-edge become sharper and stronger demonstrates that the O atom in the C=O participates in the interface interaction, which was confirmed by O1s SRPES spectrum. (authors)

Mechanical Response of Single Filamin A (ABP-280) Molecules and Its Role in the Actin/Filamin A Gel

Science.gov (United States)

Sano, Ryoko; Furuike, Shou; Ito, Tadanao; Ohashi, Kazuyo; Yamazaki, Masahito

2004-04-01

Actin/filamin A gel plays important roles in mechanical response of cells. We found a force (50 to 220 pN)-induced unfolding of single filamin A molecules using AFM, and have proposed a hypothesis on the role of single filamin A in the novel property of viscoelasticity of actin/filamin A gel. We also investigated structure and its dynamics of actin/filamin A gel formed in a giant liposome using fluorescence microscopy.

Degenerative dementia: nosological aspects and results of single photon emission computed tomography

International Nuclear Information System (INIS)

Dubois, B.; Habert, M.O.

1999-01-01

Ten years ago, the diagnosis discussion of a dementia case for the old patient was limited to two pathologies: the Alzheimer illness and the Pick illness. During these last years, the frame of these primary degenerative dementia has fallen into pieces. The different diseases and the results got with single photon emission computed tomography are discussed. for example: fronto-temporal dementia, primary progressive aphasia, progressive apraxia, visio-spatial dysfunction, dementia at Lewy's bodies, or cortico-basal degeneration. (N.C.)

Low inductance diode design on the Proto II accelerator for imploding plasma loads

International Nuclear Information System (INIS)

Hsing, W.W.; Coats, R.; McDaniel, D.H.; Spielman, R.B.

1985-01-01

A new water transmission line convolute, single piece insulator, and double disk feed has been designed and tested on the .125 ohm, 10 TW Proto II accelerator. The water transmission lines have a 5 cm gap to eliminate any water arcing. A two-dimensional magnetic field code was used to calculate the convolute inductance. The authors used an acrylic insulator as well as a single piece, laminated polycarbonate insulator. They have been successfully tested at over 90% of the Shipman criteria for classical insulator breakdown, although the laminations in the polycarbonate insulator failed after a few shots. The anode and cathode each have two pieces and are held together mechanically. The vacuum MITL tapers to a 3 mm minimum gap. The total inductance is 8.4 nH for gas puff loads and 7.8 nH for imploding foil loads

Memory structures for encoding and retrieving a piece of music: an ERP investigation.

Science.gov (United States)

Williamon, Aaron; Egner, Tobias

2004-12-01

This study examined behavioral and neural correlates of expert musical memory, specifically the hypothesis that particular bars within a complex piece of music would serve as structural markers for encoding to and retrieval from memory. Six pianists were asked to learn and memorize a set prelude by J.S. Bach for performance, and to identify bars that they employed for structuring the prelude into component sections. Following performance from memory, the participants took part in a visual recognition memory task, in which single bars from the prelude had to be distinguished from matched new bars. During the recognition task, the electroencephalogram (EEG) was recorded, and event-related potentials (ERPs) from correctly identified prelude stimulus trials were averaged according to their hypothesized status into "structural" and "nonstructural" bars. The results showed that correct identification of structural bars was significantly faster (and tended to display higher accuracy) than recognition of non-structural ones. In addition, recognition of structural bars was associated with a significantly greater negative ERP peak of 300-400 ms latency and a right centro-parietal scalp distribution. This mid-latency negativity appears to index processing of stimuli that served as cues for encoding and retrieval of a complex semantic structure, and is qualitatively and conceptually different from other previously identified recognition memory ERPs (such as the "old/new" effect), as well as from the classic N400 ERP. The data support existing theories of expert memory and music cognition.

Effect of Single and Double Stage Chemically Treated Kenaf Fibers on Mechanical Properties of Polyvinyl Alcohol Film

Directory of Open Access Journals (Sweden)

Md Ershad Ali

2014-12-01

Full Text Available The physico-mechanical properties of lignocellulosic kenaf fiber reinforced polyvinyl alcohol (PVA biocomposite films were investigated. To improve the properties of the biocomposite, kenaf fibers were chemically treated separately in a single stage (with Cr2(SO4312(H2O and double stages (with CrSO4 and NaHCO3 to improve the adhesion and compatibility between the kenaf fiber and PVA matrix. PVA was reinforced with various compositions of chemically treated kenaf fiber by using a solution casting technique. Microstructural analyses and mechanical tests were subsequently conducted. Scanning electron microscopic analysis indicated that chemical treatment improved the uniformity distribution of kenaf fiber within the PVA matrix. FTIR and XRD analyses confirmed the presence of chromium on the fiber surface. The tensile strength of PVA reinforced with chemical treated kenaf fiber was found to be higher than those reinforced with untreated kenaf. The Young’s modulus, flexural strength, and flexural modulus increased with fiber loading for both untreated and treated kenaf fiber reinforced PVA films. The double stage treated kenaf fiber showed better mechanical properties and lower moisture uptake than the single stage treated kenaf fiber.

The role of prosthetic abutment material on the stress distribution in a maxillary single implant-supported fixed prosthesis

International Nuclear Information System (INIS)

Peixoto, Hugo Eduardo; Bordin, Dimorvan; Del Bel Cury, Altair A.; Silva, Wander José da; Faot, Fernanda

2016-01-01

Purpose: Evaluate the influence of abutment's material and geometry on stress distribution in a single implant-supported prosthesis. Materials and Methods: Three-dimensional models were made based on tomographic slices of the upper middle incisor area, in which a morse taper implant was positioned and a titanium (Ti) or zirconia (ZrN) universal abutments was installed. The commercially available geometry of titanium (T) and zirconia (Z) abutments were used to draw two models, TM1 and ZM1 respectively, which served as control groups. These models were compared with 2 experimental groups were the mechanical properties of Z were applied to the titanium abutment (TM2) and vice versa for the zirconia abutment (ZM2). Subsequently, loading was simulated in two steps, starting with a preload phase, calculated with the respective friction coefficients of each materials, followed by a combined preload and chewing force. The maximum von Mises stress was described. Data were analyzed by two-way ANOVA that considered material composition, geometry and loading (p 0.05). Conclusion: The screw was the piece most intensely affected, mainly through the preload force, independent of the abutment's material. - Highlights: • The abutment's screw was the most impaired piece of the dental implant system. • The highest stress was located at first thread of the abutment's screw. • The preload is the main factor in the abutment's screw stress. • Abutment configuration and material can have a positive contribution for the stress distribution

[Development of whole process quality control and management system of traditional Chinese medicine decoction pieces based on traditional Chinese medicine quality tree].

Science.gov (United States)

Yu, Wen-Kang; Dong, Ling; Pei, Wen-Xuan; Sun, Zhi-Rong; Dai, Jun-Dong; Wang, Yun

2017-12-01

The whole process quality control and management of traditional Chinese medicine (TCM) decoction pieces is a system engineering, involving the base environment, seeds and seedlings, harvesting, processing and other multiple steps, so the accurate identification of factors in TCM production process that may induce the quality risk, as well as reasonable quality control measures are very important. At present, the concept of quality risk is mainly concentrated in the aspects of management and regulations, etc. There is no comprehensive analysis on possible risks in the quality control process of TCM decoction pieces, or analysis summary of effective quality control schemes. A whole process quality control and management system for TCM decoction pieces based on TCM quality tree was proposed in this study. This system effectively combined the process analysis method of TCM quality tree with the quality risk management, and can help managers to make real-time decisions while realizing the whole process quality control of TCM. By providing personalized web interface, this system can realize user-oriented information feedback, and was convenient for users to predict, evaluate and control the quality of TCM. In the application process, the whole process quality control and management system of the TCM decoction pieces can identify the related quality factors such as base environment, cultivation and pieces processing, extend and modify the existing scientific workflow according to their own production conditions, and provide different enterprises with their own quality systems, to achieve the personalized service. As a new quality management model, this paper can provide reference for improving the quality of Chinese medicine production and quality standardization. Copyright© by the Chinese Pharmaceutical Association.

Use of large pieces of printed circuit boards for bioleaching to avoid ‘precipitate contamination problem’ and to simplify overall metal recovery

Science.gov (United States)

Adhapure, N.N.; Dhakephalkar, P.K.; Dhakephalkar, A.P.; Tembhurkar, V.R.; Rajgure, A.V.; Deshmukh, A.M.

2014-01-01

Very recently bioleaching has been used for removing metals from electronic waste. Most of the research has been targeted to using pulverized PCBs for bioleaching where precipitate formed during bioleaching contaminates the pulverized PCB sample and making the overall metal recovery process more complicated. In addition to that, such mixing of pulverized sample with precipitate also creates problems for the final separation of non metallic fraction of PCB sample. In the present investigation we attempted the use of large pieces of printed circuit boards instead of pulverized sample for removal of metals. Use of large pieces of PCBs for bioleaching was restricted due to the chemical coating present on PCBs, the problem has been solved by chemical treatment of PCBs prior to bioleaching. In short,•Large pieces of PCB can be used for bioleaching instead of pulverized PCB sample.•Metallic portion on PCBs can be made accessible to bacteria with prior chemical treatment of PCBs.•Complete metal removal obtained on PCB pieces of size 4 cm × 2.5 cm with the exception of solder traces. The final metal free PCBs (non metallic) can be easily recycled and in this way the overall recycling process (metallic and non metallic part) of PCBs becomes simple. PMID:26150951

Burning of MOX fuels in LWRs; fuel history effects on thermal properties of hull and end piece wastes and the repository performance

International Nuclear Information System (INIS)

Hirano, Fumio; Sato, Seichi; Kozaki, Tamotsu

2012-01-01

The thermal impacts of hull and end piece wastes from the reprocessing of MOX spent fuels burned in LWRs on repository performance were investigated. The heat generation rates in MOX spent fuels and the resulting heat generation rates in hull and end piece wastes change depending on the history of MOX fuels. This history includes the burn-up of UO 2 spent fuels from which the Pu is obtained, the cooling period before reprocessing, the storage period of fresh MOX fuels before being loaded into an LWR, as well as the burn-up of the MOX fuels. The heat generation rates in hull and end piece wastes from the reprocessing of MOX spent fuels with any of those histories are significantly larger than those from UO 2 spent fuels with burn-ups of 45 GWd/THM. If a temperature below 80degC is specified for cement-based materials used in waste packages after disposal, the allowable number of canisters containing compacted hull and end pieces in a package for 45 and 70 GWd-MOX needs to be limited to a value of 0.4-1.6, which is significantly lower than 4.0 for 45 GWd-UO 2 . (author)

Marginal Micro-leakage of Self-etch and All-in One Adhesives to Primary Teeth, with Mechanical or Chemo-Mechanical Caries Removal

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Nouzari A

2016-06-01

Full Text Available Statement of Problem: Chemo-mechanical caries removal is an effective alternative to the traditional rotary drilling method. One of the factors that can influence micro-leakage is the method of caries removal. Objectives: To compare the micro-leakage of resin composite in primary dentition using self-etch and all-in one adhesives following conventional and chemo-mechanical caries removal. Materials and Methods: Sixty extracted human primary anterior teeth with class III carious lesions were collected. The selected teeth were divided randomly into two groups each consisting of 30 teeth. In group1 carious lesions were removed using Carisolv multi mix gel. In group 2, caries was removed using round steel burs in a slow–speed hand piece. Then, the specimens in each group were randomly divided into two subgroups (A and B of 15 and treated by either Clearfil SE Bond (CSEB or Scotch bond. All prepared cavities were filled with a resin composite (Estellite. All the specimens were stored in distilled water at 37ºC for 24 hours and then thermocycled in 5ºC and 55ºC water with a dwell time of 20 seconds for 1500 cycles. The specimens were immersed in 1% methylene blue solution for 24 hours, removed, washed and sectioned mesiodistally. The sectioned splits were examined under a stereomicroscope to determine the micro-leakage scores. The data were analyzed using Kruskal-Wallis Test in SPSS version 21. Results: There were no significant differences between micro-leakage scores among the four groups (p = 0.127. Score 0 of micro-leakage was detected for 60% of the specimens in group 1-A (Carisolv + CSEB, 73% of the group 2-A (hand piece + CSEB, 80% of the group 1-B (Carisolv + Scotch bond, and 93% of the group 2-B in which caries was removed using hand piece and bonded with Scotch bond . Conclusions: Although caries removal using hand piece bur along with using Scotch bond adhesive performed less micro-leakage, it would seems that the use of Carisolv

Large area spark chamber and support, and method of recording and analyzing the information on a radioactive work piece

International Nuclear Information System (INIS)

Britten, R.J.; Davidson, E.H.

1985-01-01

Novel large area spark chamber having a support for carrying a generally planar, radioactive work piece. The spark chamber has a thin window which is either a rigid plastic sheet carrying a thin layer of an electrically conductive material on the surface thereof, or a thin planar piece or film of electrically conductive metal. There is positioned in superposed relationship to the thin window, a layer of semi-conducting glass in spaced-apart relationship from the thin window by a resilient insulating seal to form an enclosed gas retaining chamber. An electrically conducting surface is adhered to the upper surface of the layer of semi-conducting glass. An electrically conductive path is provided between the thin layer of electrically conductive material on the thin window and the electrically conducting surface on said semi-conducting glass. The electrically conductive path includes a high voltage supply and TDCs and ADCs. There are also means for detecting the location of sites of impingement of radiation on the electrically conducting surface of the semi-conducting glass, and means for recording and analyzing the information present on the work piece

Study in electron microscopy the formation of the hybrid layer using adhesive systems One Coat and Single Bond Universal, at the Facultad de Medicina of the Universidad de Costa Rica

International Nuclear Information System (INIS)

Parra Barillas, Adriana; Montoya, Michael

2013-01-01

The formation of the hybrid layer is observed in dental pieces in vitro, using systems of conventional adhesives (Single Bond 2 of 3M and One Coat of Coltene), with different times of acid etching, through the use of atomic force microscopy (AFM). The images of the hybrid layer obtained from samples prepared with adhesive systems are analyzed by AFM. Samples collected have been of dental pieces (molars and premolars) recently extracted and later placed in water. The pieces used have provided more surface to be observed under the microscope, greater accessibility to the be cut for its study, and to the great pieces have facilitated their placement on the Isomet low speed saw. The differences are evaluated between hybrid layers according the adhesive system used and the mode of application of the images obtained in the atomic force microscope. The adhesive system that has allowed the formation of a hybrid layer more appropriate between the adhesive system One Coat and the adhesive system Single Bond Universal is determined. The time of acid etching as variable of procedure is determined and has interfered with the formation of a hybrid layer more stable. The images evaluated that were provided by the atomic force microscope and compared with the images of electron microscopy of other studies, have determined that the AFM is without providing detailed information, as well as the appropriate images to evaluate the hybrid layer of the adhesive systems Single Bond 2 and One Coat of Coltene, or the different times of acid etching. Therefore, for this type of study, the image of choice must be of an electron microscope [es

Implications of the single supervisory mechanism on ECB's functions and on credit institutions' activity

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Teodora Cristina BARBU

2013-03-01

Full Text Available The European Commission's proposal launched on September 12, 2012 for conferring the European Central Bank extended powers in the field of Euro zone banking supervision has become a hotly debated topic across EU member states. Until now, there is still strong resilience of the EU countries outside the single currency area.The prospects for its practical implementation raised, however, a series of questions related to its technical feasibility. Our paper intends to shed light on some issues concerning the implications of the single monitoring mechanism on the traditional functions of the ECB, on the coexistence between supranational supervision and the national one, and on various facets of the impact that the new architecture of European banking supervision will have on the business of credit institutions, in terms of performance indicators, efficiency, risk and competition.

The Arrangement for My Funny Valentine by Marco Pereira: Leadsheet to Piece

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Rafael Thomaz

2013-05-01

Full Text Available his article presents an analysis of the arrangement made by the Brazilian guitarist Marco Pereira for the American song My Funny Valentine in order to explore and understand the transformation of an open structured theme of a popular song into a closed structured piece for a solo instrument. For this purpose, a brief history of the hybridization of Brazilian music was outlined emphasizing solo guitar and an approach to the specific aspects and potential of using the leadsheet and conventional score.

Mobility-limiting mechanisms in single and dual channel strained Si/SiGe MOSFETs

International Nuclear Information System (INIS)

Olsen, S.H.; Dobrosz, P.; Escobedo-Cousin, E.; Bull, S.J.; O'Neill, A.G.

2005-01-01

Dual channel strained Si/SiGe CMOS architectures currently receive great attention due to maximum performance benefits being predicted for both n- and p-channel MOSFETs. Epitaxial growth of a compressively strained SiGe layer followed by tensile strained Si can create a high mobility buried hole channel and a high mobility surface electron channel on a single relaxed SiGe virtual substrate. However, dual channel n-MOSFETs fabricated using a high thermal budget exhibit compromised mobility enhancements compared with single channel devices, in which both electron and hole channels form in strained Si. This paper investigates the mobility-limiting mechanisms of dual channel structures. The first evidence of increased interface roughness due to the introduction of compressively strained SiGe below the tensile strained Si channel is presented. Interface corrugations degrade electron mobility in the strained Si. Roughness measurements have been carried out using AFM and TEM. Filtering AFM images allowed roughness at wavelengths pertinent to carrier transport to be studied and the results are in agreement with electrical data. Furthermore, the first comparison of strain measurements in the surface channels of single and dual channel architectures is presented. Raman spectroscopy has been used to study channel strain both before and after processing and indicates that there is no impact of the buried SiGe layer on surface macrostrain. The results provide further evidence that the improved performance of the single channel devices fabricated using a high thermal budget arises from improved surface roughness and reduced Ge diffusion into the Si channel

Effect of shrinkage porosity on mechanical properties of ferritic ductile iron

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Wang Zehua

2013-05-01

Full Text Available Casting defects could largely affect the mechanical properties of casting products. A number of test pieces made of ductile iron (EN-GJS-400-18-LT with different levels of shrinkage porosity were prepared and then tensile and fatigue tests were performed to investigate the impact of shrinkage porosity on their mechanical properties. The results showed that the tensile strength decreases linearly with increasing of the shrinkage porosity. The tensile elongation decreases sharply with the increase of the shrinkage porosity mainly due to the non-uniform plastic deformation. The fatigue life also dramatically declines with increasing of the porosity and follows a power law relationship with the area percentage of porosity. The existence of the shrinkage porosity made the fatigue fracture complex. The shrinkage pores, especially those close to the surface usually became the crack initiation sites. For test pieces with less porosity, the fatigue fracture was clearly composed of crack initiation, propagation, and overloading. While for samples with high level of porosity, multiple crack initiation sites were observed.

Continuous sedation until death: moral justifications of physicians and nurses-a content analysis of opinion pieces

NARCIS (Netherlands)

Rys, S.; Mortier, F.; Deliens, L.; Deschepper, R.; Battin, M.P.; Bilsen, J.

2013-01-01

Continuous sedation until death (CSD), the act of reducing or removing the consciousness of an incurably ill patient until death, often provokes medical-ethical discussions in the opinion sections of medical and nursing journals. A content analysis of opinion pieces in medical and nursing literature

Mechanisms for Selective Single-Cell Reactivation during Offline Sharp-Wave Ripples and Their Distortion by Fast Ripples.

Science.gov (United States)

Valero, Manuel; Averkin, Robert G; Fernandez-Lamo, Ivan; Aguilar, Juan; Lopez-Pigozzi, Diego; Brotons-Mas, Jorge R; Cid, Elena; Tamas, Gabor; Menendez de la Prida, Liset

2017-06-21

Memory traces are reactivated selectively during sharp-wave ripples. The mechanisms of selective reactivation, and how degraded reactivation affects memory, are poorly understood. We evaluated hippocampal single-cell activity during physiological and pathological sharp-wave ripples using juxtacellular and intracellular recordings in normal and epileptic rats with different memory abilities. CA1 pyramidal cells participate selectively during physiological events but fired together during epileptic fast ripples. We found that firing selectivity was dominated by an event- and cell-specific synaptic drive, modulated in single cells by changes in the excitatory/inhibitory ratio measured intracellularly. This mechanism collapses during pathological fast ripples to exacerbate and randomize neuronal firing. Acute administration of a use- and cell-type-dependent sodium channel blocker reduced neuronal collapse and randomness and improved recall in epileptic rats. We propose that cell-specific synaptic inputs govern firing selectivity of CA1 pyramidal cells during sharp-wave ripples. Copyright © 2017 Elsevier Inc. All rights reserved.

Extended long term functional outcome of inflatable penile prosthesis in a single institution.

LENUS (Irish Health Repository)

Thomas, A Z

2011-02-01

We sought to evaluate the extended long term functional outcome of the AMS700 three piece inflatable prosthesis in men with erectile dysfunction in a single urological department and assess our revision rates. Patients that underwent first-time insertion or revision of an AMS700 3 piece inflatable penile prosthesis between 1984-2007 were included. Data was obtained from medical records and long term follow up of patients was conducted by telephone interview. The medical records of 38 patients were available for review. Of these 38 men, 56 prostheses were inserted. The mean follow up was 8.4 years (101 months). The revision rate at 50 months postoperatively was 7\\/38 (18%). The overall revision rate was 18\\/38 (47%). The mean time to revision in these 18 patients was 72 months (12-156 months) after initial insertion of AMS700 penile prosthesis. This study highlights that with longer follow u revision rates markedly increase after 72 months.

Exploring Transduction Mechanisms of Protein Transduction Domains (PTDs in Living Cells Utilizing Single-Quantum Dot Tracking (SQT Technology

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Yasuhiro Suzuki

2012-01-01

Full Text Available Specific protein domains known as protein transduction domains (PTDs can permeate cell membranes and deliver proteins or bioactive materials into living cells. Various approaches have been applied for improving their transduction efficacy. It is, therefore, crucial to clarify the entry mechanisms and to identify the rate-limiting steps. Because of technical limitations for imaging PTD behavior on cells with conventional fluorescent-dyes, how PTDs enter the cells has been a topic of much debate. Utilizing quantum dots (QDs, we recently tracked the behavior of PTD that was derived from HIV-1 Tat (TatP in living cells at the single-molecule level with 7-nm special precision. In this review article, we initially summarize the controversy on TatP entry mechanisms; thereafter, we will focus on our recent findings on single-TatP-QD tracking (SQT, to identify the major sequential steps of intracellular delivery in living cells and to discuss how SQT can easily provide direct information on TatP entry mechanisms. As a primer for SQT study, we also discuss the latest findings on single particle tracking of various molecules on the plasma membrane. Finally, we discuss the problems of QDs and the challenges for the future in utilizing currently available QD probes for SQT. In conclusion, direct identification of the rate-limiting steps of PTD entry with SQT should dramatically improve the methods for enhancing transduction efficiency.

Inertial piezoelectric linear motor driven by a single-phase harmonic wave with automatic clamping mechanism

Science.gov (United States)

He, Liangguo; Chu, Yuheng; Hao, Sai; Zhao, Xiaoyong; Dong, Yuge; Wang, Yong

2018-05-01

A novel, single-phase, harmonic-driven, inertial piezoelectric linear motor using an automatic clamping mechanism was designed, fabricated, and tested to reduce the sliding friction and simplify the drive mechanism and power supply control of the inertial motor. A piezoelectric bimorph and a flexible hinge were connected in series to form the automatic clamping mechanism. The automatic clamping mechanism was used as the driving and clamping elements. A dynamic simulation by Simulink was performed to prove the feasibility of the motor. The finite element method software COMSOL was used to design the structure of the motor. An experimental setup was built to validate the working principle and evaluate the performance of the motor. The prototype motor outputted a no-load velocity of 3.178 mm/s at a voltage of 220 Vp-p and a maximum traction force of 4.25 N under a preload force of 8 N. The minimum resolution of 1.14 μm was achieved at a driving frequency of 74 Hz, a driving voltage of 50 Vp-p, and a preload force of 0 N.

Numerical Modeling of the Work Piece Region in the Plasma Arc Cutting Process

Science.gov (United States)

Osterhouse, David

The plasma arc cutting process is widely used for the cutting of metals. The process, however, is not fully understood and further understanding will lead to further improvements. This work aims to elucidate the fundamental physical phenomena in the region where the plasma interacts with the work piece through the use of numerical modeling techniques. This model follows standard computational fluid dynamic methods that have been suitably modified to include plasma effects, assuming either local thermodynamic equilibrium or a slight non-equilibrium captured by the two-temperature assumption. This is implemented in the general purpose, open source CFD package, OpenFOAM. The model is applied to a plasma flow through a geometry that extends from inside the plasma torch to the bottom of the slot cut in the work piece. The shape of the kerf is taken from experimental measurements. The results of this model include the temperature, velocity, and electrical current distribution throughout the plasma. From this, the heat flux to and drag force on the work piece are calculated. The location of the arc attachment in the cut slot is also noted because it is a matter of interest in the published literature as well as significantly effecting the dynamics of the heat flux and drag force. The results of this model show that the LTE formulation is not sufficient to capture the physics present due to unphysical fluid dynamic instabilities and numerical problems with the arc attachment. The two-temperature formulation, however, captures a large part of the physics present. Of particular note, it is found that an additional inelastic collision factor is necessary to describe the increased energy transfer between electrons and diatomic molecules, which is widely neglected in published literature. It is also found that inclusion of the oxygen molecular ion is necessary to accurately describe the plasma flow, which has been neglected in all published two-temperature oxygen calculations

Immediate prostheses on one-piece trans-mucosal implants in flapless surgical procedures Case Series Report. Part I: full arch rehabilitations

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Aris Petros Tripodakis

2012-06-01

Full Text Available Aim: The aim of the present case series report is to illustrate a clinical technique and present the application of onepiece transmucosal implants in flapless surgical procedures, supporting full arch immediate prostheses. Materials and methods: A total of 294 implants (Xive TG, Friadent, Germany have been used to support full arch immediate prostheses, over the last six years and have been in function for at least one year. The surgical placement of five or more implants per case involved immediate extraction and intrasocket flapless placement, combined with minimal flap elevation in the areas of healed extraction sites (43 mandibular and 7 maxillary arches. In all cases immediate provisionalization followed. Detailed three-dimensional cone-beam localized volumetric tomography preceeded the surgical procedures. The delivery of the final ceramo-metal prostheses was accomplished within a 20 day period. Materials and methods: Results Six implants failed to osseointegrate. All other implants are still successfully bearing the final prosthesis for the time that they have been followed. Soft tissue reaction was favorable from both the biologic and esthetic point of view. Conclusion: The flapless placement of one piece implants into edentulous healed sites is a predictable procedure in the presence of abundance of supporting bone as confirmed by 3-D imaging. On the other hand, immediate extraction placement of one piece implants allows the engagement of sound bone located deeper into the socket and provides adequate mechanical support of the soft tissue architecture that is preserved predictably. In all cases the prosthetic procedures are accomplished without disturbing the hardsoft tissue interface as the abutment-prosthesis interface is coronally elevated by the virtual design of the implant.

Mechanical properties of pure and doped InP single crystals under concentrated loading

International Nuclear Information System (INIS)

Boyarskaya, Yu.S.; Grabko, D.Z.; Medinskaya, M.I.; Palistrant, N.A.

1997-01-01

The mechanical properties of pure and doped (Fe, Zn, Sn) InP single crystals were investigated in the temperature interval from 293 to 600 K. It was shown that impurity hardening (the microhardness increase) was more pronounced at elevated temperatures than at 293 K. This is conditioned by braking of the moving dislocations with impurities which is more observed in the the high temperature region. The obvious anisotropy of the scratch hardness was revealed at room temperature for the (001) face of crystals under investigation. This anisotropy decreased sharply in increasing the temperature from 293 to 600 K

OPTIMIZING THE PLACEMENT OF A WORK-PIECE AT A MULTI-POSITION ROTARY TABLE OF TRANSFER MACHINE WITH VERTICAL MULTI-SPINDLE HEAD

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N. N. Guschinski

2015-01-01

Full Text Available The problem of minimizing the weight of transfer machine with a multi-position rotary table by placing of a work-piece at the table for processing of homogeneous batch of work-pieces is considered. To solve this problem the mathematical model and heuristic particle swarm optimization algorithm are proposed. The results of numerical experiments for two real problems of this type are given. The experiments revealed that the particle swarm optimization algorithm is more effective for the solution of the problem compared to the methods of random search and LP-search.

Micro-pulse polarization lidar at 1.5  μm using a single superconducting nanowire single-photon detector.

Science.gov (United States)

Qiu, Jiawei; Xia, Haiyun; Shangguan, Mingjia; Dou, Xiankang; Li, Manyi; Wang, Chong; Shang, Xiang; Lin, Shengfu; Liu, Jianjiang

2017-11-01

An all-fiber, eye-safe and micro-pulse polarization lidar is demonstrated with a polarization-maintaining structure, incorporating a single superconducting nanowire single-photon detector (SNSPD) at 1.5 μm. The time-division multiplexing technique is used to achieve a calibration-free optical layout. A single piece of detector is used to detect the backscatter signals at two orthogonal states in an alternative sequence. Thus, regular calibration of the two detectors in traditional polarization lidars is avoided. The signal-to-noise ratio of the lidar is guaranteed by using an SNSPD, providing high detection efficiency and low dark count noise. The linear depolarization ratio (LDR) of the urban aerosol is observed horizontally over 48 h in Hefei [N31°50'37'', E117°15'54''], when a heavy air pollution is spreading from the north to the central east of China. Phenomena of LDR bursts are detected at a location where a building is under construction. The lidar results show good agreement with the data detected from a sun photometer, a 532 nm visibility lidar, and the weather forecast information.

[Powder modification technology used for the preparation of the hydrophilic decoction pieces of indigo naturalis and the modification principle].

Science.gov (United States)

Zhang, Ding-Kun; Lin, Jun-Zhi; Liu, Jian-Yun; Qin, Chun-Feng; Guo, Zhi-Ping; Han, Li; Yang, Ming

2013-07-01

The hydrophilicity of the normal decoction pieces (NDP) of Indigo Naturalis is not good, therefore, it is not suit for decoctions. In this paper, powder modification technology is used and some NDP and alcohol are ground together in the vibromill to prepare the hydrophilic decoction pieces (HDP) of Indigo Naturalis. Initially, the properties of NDP, ultrafine decoction pieces (UDP) and HDP are compared, the hydrophilicity of UDP was promoted slightly, that of HDP is promoted dramatically. Then, three batches of Indigo Naturalis are prepared to HDP separately, but there is no obvious difference in the contact angle. Furthermore, the size distribution, surface area and micro-shape of HDP are bigger than that of UDP and smaller than NDP. The contents of indigo and indirubin in three decoction pieces are the same, as well as the species of inorganic substance, although there is a little difference in the proportion of five inorganic substances. The fact suggests the change of physical state and the qualitative and quantitative change of organism and inorganic substances are not the main factors to influence the hydrophilicity. In addition, hydroxyl, methylene and methyl can be identified at the wavenumber of 3 356 cm(-1) and 1 461 cm(-1) in infrared spectrum; the content of alcohol in HDP is 0.67% measured by gas chromatogram. The stability of HDP in the heating condition is studied, the fact suggests the hydrophilic effect of HDP at 40 degrees C is relatively stable. All above research suggests that the alcohol is the main factor to influence the hydrophilicity and maybe the intermolecular force which fixed alcohol molecule on the surface of Indigo Naturalis is the basic principle to produce the hydrophilicity.

Piezoresistivity of mechanically drawn single-walled carbon nanotube (SWCNT) thin films-: mechanism and optimizing principle

Science.gov (United States)

Obitayo, Waris

The individual carbon nanotube (CNT) based strain sensors have been found to have excellent piezoresistive properties with a reported gauge factor (GF) of up to 3000. This GF on the other hand, has been shown to be structurally dependent on the nanotubes. In contrast, to individual CNT based strain sensors, the ensemble CNT based strain sensors have very low GFs e.g. for a single walled carbon nanotube (SWCNT) thin film strain sensor, GF is ~1. As a result, studies which are mostly numerical/analytical have revealed the dependence of piezoresistivity on key parameters like concentration, orientation, length and diameter, aspect ratio, energy barrier height and Poisson ratio of polymer matrix. The fundamental understanding of the piezoresistive mechanism in an ensemble CNT based strain sensor still remains unclear, largely due to discrepancies in the outcomes of these numerical studies. Besides, there have been little or no experimental confirmation of these studies. The goal of my PhD is to study the mechanism and the optimizing principle of a SWCNT thin film strain sensor and provide experimental validation of the numerical/analytical investigations. The dependence of the piezoresistivity on key parameters like orientation, network density, bundle diameter (effective tunneling area), and length is studied, and how one can effectively optimize the piezoresistive behavior of a SWCNT thin film strain sensors. To reach this goal, my first research accomplishment involves the study of orientation of SWCNTs and its effect on the piezoresistivity of mechanically drawn SWCNT thin film based piezoresistive sensors. Using polarized Raman spectroscopy analysis and coupled electrical-mechanical test, a quantitative relationship between the strain sensitivity and SWCNT alignment order parameter was established. As compared to randomly oriented SWCNT thin films, the one with draw ratio of 3.2 exhibited ~6x increase on the GF. My second accomplishment involves studying the

Ways of Knowing and Types of Knowledge: How Do Students Approach a New Piece of Music?

Science.gov (United States)

dos Santos, Regina Antunes Teixeira; Gerling, Cristina Capparelli

2012-01-01

In an exploratory study lasting more than 16 weeks, 15 undergraduate and graduate piano students prepared a short piece by the Brazilian composer Guarnieri, "Ponteio" no. 22, without guidance from their piano teachers. The data that were collected included their performances, interviews pertaining to their practice and stimulated recall…

Single-port laparoscopic myomectomy using a new single-port transumbilical morcellation system: initial clinical study.

Science.gov (United States)

Kim, Yong-Wook; Park, Byung-Joon; Ro, Duck-Yeong; Kim, Tae-Eung

2010-01-01

To evaluate the feasibility of single-port laparoscopic myomectomy with transumbilical morcellation and suturing. Continuing prospective study (Canadian Task Force classification II-3). University hospital. Fifteen patients who underwent single-port laparoscopic myomectomy between September 2008 and October 2009 to remove single or multiple uterine myomas, at least 1 in each patient measuring greater than 4 cm in diameter. All single-port laparoscopic myomectomy procedures were performed by a single surgeon (Dr. Y.W. Kim). Myomas were extracted transumbilically by cutting the myomas into smaller pieces with a knife or a conventional electromechanical morcellator. After making a single 1.5- to 2.0-cm umbilical incision, the single-port system, created with a wound retractor and a surgical glove, was inserted. All operations were performed using conventional rigid straight laparoscopic instruments. Laparoscopic suturing was performed in intramural myomas and some subserosal myomas. Patient mean (SD; range) age was 38.3 (5.6; 29-49) years. The number of myomas per patient was 1.6 (1.4; 1-6). The diameter of the largest myomas was 6.1 (1.5; 4.2-9.6) cm. In 4 patients, only a knife was required for transumbilical extraction of myomas, and in 11 patients, transumbilical morcellation with an electromechanical morcellator with or without a knife was used. Transumbilical drainage tubes were inserted into the pelvic cavity in 11 of 15 patients. Operative time was 96.7 (33.8; 35-150) minutes. The decrease in postoperative hemoglobin concentration was 1.8 (1.2; 0.4-3.6) g/dL. During the operations, no patients required blood transfusion. No patients developed postoperative fever. Neither bowel injury nor urinary tract injury occurred in any patient. The postoperative hospital stay was 3.1 (0.8; 2-4) days. Single-port transumbilical morcellation using a conventional electromechanical morcellator with or without a knife is feasible. Single-port laparoscopic myomectomy is an

Analysis of potassium nitrate purification with recovery of solvent through single effect mechanical vapor compression

Directory of Open Access Journals (Sweden)

Kiprotich E. Kosgey

2017-12-01

Full Text Available Analysis of purification of potassium nitrate with incorporation of single effect mechanical vapor compressor for solvent recovery was done. Analysis focused on the effect of concentration and temperature of mother liquor on the energy efficiency of the process and the amount of recovered solvent. Performance coefficient of mechanical vapor compressor ranged between 1.5 and 7.5 depending primarily on the temperature of mother liquor. It was found that with increase in temperature of mother liquor through pre-heating, the power of the compressor, compression ratio and amount of heat supplied to the evaporator decrease. For a 40% concentrated feed solution and mother liquor temperature above 80 °C, performance coefficient is higher than 4. It is therefore concluded that preheating mother liquor and reduction of the effect of concentration of both mother liquor and concentrated waste stream through other methods reduces the power consumption of purification process. Keywords: Performance coefficient, Mother liquor, Concentrated solution, Recovered solvent, Boiling point elevation, Mechanical vapor compressor

Cueing musical emotions: An empirical analysis of 24-piece sets by Bach and Chopin documents parallels with emotional speech

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Matthew ePoon

2015-11-01

Full Text Available Acoustic cues such as pitch height and timing are effective at communicating emotion in both music and speech. Numerous experiments altering musical passages have shown that higher and faster melodies generally sound happier than lower and slower melodies, findings consistent with corpus analyses of emotional speech. However, equivalent corpus analyses of complex time-varying cues in music are less common, due in part to the challenges of assembling an appropriate corpus. Here we describe a novel, score-based exploration of the use of pitch height and timing in a set of balanced major and minor key compositions. Our corpus contained all 24 Preludes and 24 Fugues from Bach’s Well Tempered Clavier (book 1, as well as all 24 of Chopin’s Preludes for piano. These three sets are balanced with respect to both modality (major/minor and key chroma (A, B, C, etc.. Consistent with predictions derived from speech, we found major-key (nominally happy pieces to be two semitones higher in pitch height and 29% faster than minor-key (nominally sad pieces. This demonstrates that our balanced corpus of major and minor key pieces uses low-level acoustic cues for emotion in a manner consistent with speech. A series of post-hoc analyses illustrate interesting trade-offs, with

Data for the study of fibulae pivot in the Iberian Peninsula. The piece of Cerro de la Mora (Moraleda de Zafayona, Granada

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Javier CARRASCO RUS

2016-07-01

Full Text Available Due to the complexity of the archaic elbow fibulae of the Iberian Peninsula, our work traits to organize the pivot group. First, its mechanics and conceptualization are defined precisely. Later, an analysis of the previous known facts is done, taking into account its cultural ascription, its chronology, its territorial distribution, its morphology and its technology. This analysis is made with the idea of advancing a viable typologic organisation. To realise the work some representative fibulae are considered, especially those more relevant. The criteria used to select these are its contextualization, its metalic composition, internal relation and time and space characteristics. There are no references to fibulae from out of the Peninsula. The main conclusion of the article is that these pieces are older than what was though in the traditional interpretations.

On Limitations of the Ultrasonic Characterization of Pieces Manufactured with Highly Attenuating Materials

Science.gov (United States)

Ramos, A.; Moreno, E.; Rubio, B.; Calas, H.; Galarza, N.; Rubio, J.; Diez, L.; Castellanos, L.; Gómez, T.

Some technical aspects of two Spanish cooperation projects, funded by DPI and Innpacto Programs of the R&D National Plan, are discussed. The objective is to analyze the common belief about than the ultrasonic testing in MHz range is not a tool utilizable to detect internal flaws in highly attenuating pieces made of coarse-grained steel. In fact high-strength steels, used in some safe industrial infrastructures of energy & transport sectors, are difficult to be inspected using the conventional "state of the art" in ultrasonic technology, due to their internal microstructures are very attenuating and coarse-grained. It is studied if this inspection difficulty could be overcome by finding intense interrogating pulses and advanced signal processing of the acquired echoes. A possible solution would depend on drastically improving signal-to-noise-ratios, by applying new advances on: ultrasonic transduction, HV electronics for intense pulsed driving of the testing probes, and an "ad-hoc" digital processing or focusing of the received noisy signals, in function of each material to be inspected. To attain this challenging aim on robust steel pieces would open the possibility of obtaining improvements in inspecting critical industrial components made of highly attenuating & dispersive materials, as new composites in aeronautic and motorway bridges, or new metallic alloys in nuclear area, where additional testing limitations often appear.

Essays on the history of mechanical engineering

CERN Document Server

Genchi, Giuseppe

2016-01-01

This book treats several subjects from the History of Mechanism and Machine Science, and also contains an illustrative presentation of the Museum of Engines and Mechanisms of the University of Palermo, Italy, which houses a collection of various pieces of machinery from the last 150 years. The various sections deal with some eminent scientists of the past, with the history of industrial installations, machinery and transport, with the human inventiveness for mechanical and scientific devices, and with robots and human-driven automata. All chapters have been written by experts in their fields. The volume shows a wide-ranging panorama on the historical progress of scientific and technical knowledge in the past centuries. It will stimulate new research and ideas for those involved in the history of Science and Technology.

Mechanical design optimization of a single-axis MOEMS accelerometer based on a grating interferometry cavity for ultrahigh sensitivity

Science.gov (United States)

Lu, Qianbo; Bai, Jian; Wang, Kaiwei; Lou, Shuqi; Jiao, Xufen; Han, Dandan; Yang, Guoguang

2016-08-01

The ultrahigh static displacement-acceleration sensitivity of a mechanical sensing chip is essential primarily for an ultrasensitive accelerometer. In this paper, an optimal design to implement to a single-axis MOEMS accelerometer consisting of a grating interferometry cavity and a micromachined sensing chip is presented. The micromachined sensing chip is composed of a proof mass along with its mechanical cantilever suspension and substrate. The dimensional parameters of the sensing chip, including the length, width, thickness and position of the cantilevers are evaluated and optimized both analytically and by finite-element-method (FEM) simulation to yield an unprecedented acceleration-displacement sensitivity. Compared with one of the most sensitive single-axis MOEMS accelerometers reported in the literature, the optimal mechanical design can yield a profound sensitivity improvement with an equal footprint area, specifically, 200% improvement in displacement-acceleration sensitivity with moderate resonant frequency and dynamic range. The modified design was microfabricated, packaged with the grating interferometry cavity and tested. The experimental results demonstrate that the MOEMS accelerometer with modified design can achieve the acceleration-displacement sensitivity of about 150μm/g and acceleration sensitivity of greater than 1500V/g, which validates the effectiveness of the optimal design.

Case presentation of two maxillectomy patients restored with two-piece hollow bulb obturator retained using two different types of magnets

Directory of Open Access Journals (Sweden)

B Devi Parameswari

2017-01-01

Full Text Available Palatal defect can be repaired by reconstructive surgery and/or a dental prosthesis. We present prosthodontic rehabilitation of two partially edentulous patients, both with surgically induced palatal defect and explains how to achieve the goal for esthetics and phonetics. This also describes the fabrication of a hollow obturator by two piece method, which is simple and may be used as definitive obturator for maximum comfort of the patient. In both the above cases, since the mouth opening is restricted due to surgery, obturator prosthesis is given as two pieces retained with opposite poles of magnet, which facilitates the removal and insertion of the prosthesis.

Case Presentation of Two Maxillectomy Patients Restored with Two-piece Hollow Bulb Obturator Retained using Two Different Types of Magnets.

Science.gov (United States)

Parameswari, B Devi; Rajakumar, M; Jagadesaan, N; Annapoorni, H

2017-11-01

Palatal defect can be repaired by reconstructive surgery and/or a dental prosthesis. We present prosthodontic rehabilitation of two partially edentulous patients, both with surgically induced palatal defect and explains how to achieve the goal for esthetics and phonetics. This also describes the fabrication of a hollow obturator by two piece method, which is simple and may be used as definitive obturator for maximum comfort of the patient. In both the above cases, since the mouth opening is restricted due to surgery, obturator prosthesis is given as two pieces retained with opposite poles of magnet, which facilitates the removal and insertion of the prosthesis.

Advanced Propfan Engine Technology (APET) definition study, single and counter-rotation gearbox/pitch change mechanism design

Science.gov (United States)

Anderson, R. D.

1985-01-01

Single-rotation propfan-powered regional transport aircraft were studied to identify key technology development issues and programs. The need for improved thrust specific fuel consumption to reduce fuel burned and aircraft direct operating cost is the dominant factor. Typical cycle trends for minimizing fuel consumption are reviewed, and two 10,000 shp class engine configurations for propfan propulsion systems for the 1990's are presented. Recommended engine configurations are both three-spool design with dual spool compressors and free power turbines. The benefits of these new propulsion system concepts were evaluated using an advanced airframe, and results are compared for single-rotation propfan and turbofan advanced technology propulsion systems. The single-rotation gearbox is compared to a similar design with current technology to establish the benefits of the advanced gearbox technology. The conceptual design of the advanced pitch change mechanism identified a high pressure hydraulic system that is superior to the other contenders and completely external to the gearboxes.

Study of Using Excess Stock to Reduce Naval Aviation Depot-Level Repairable Piece Part Backorders

Science.gov (United States)

2016-12-01

used to develop and run the comparison of the backorders and excess stock records. Python is chosen because of its ease of learning and use...sustainable source of bit-piece parts for future requisitions. 14. SUBJECT TERMS naval aviation AVDLRs, backorder, excess, DLA, WSS, FRC, Python ...SCHOOL December 2016 Approved by: Geraldo Ferrer Eddine Dahel Peter Ward Bryan Hudgens Academic Associate

Single and competitive adsorption of OMPs by carbon nanotubes – mechanism and fitting models

Directory of Open Access Journals (Sweden)

Kamińska Gabriela

2017-01-01

Full Text Available The adsorption of three organic micropollutants (diclofenac – DFN, pentachlorophenol – PCP and octylphenol – OP on two kinds of carbon nanotubes (single walled carbon nanotubes – SWCNT and single walled carbon nanotubes with amine group – SWCNT-NH2 was investigated, in single and bicomponent solution at pH 5. SWCNT-NH2 had three times lower specific surface area than SWCNT. Significant differences were observed in sorption capacity of SWCNT and SWCNT-NH2 for given chemicals. The sorption uptake changes in the following order: OP > PCP > DFN for SWCNT and DFN > PCP > OP for SWCNT-NH2. A few times higher adsorption of OP on SWCNT came from low OP solubility in water in comparison to PCP and DFN. While, higher adsorption of DFN and PCP on SWCNT-NH2 was a result of electrostatic attraction between dissociated form of these chemicals and positively charged SWCNT-NH2 at pH 5. In adsorption from bicomponent solution, significant competition was observed between PCP and DFN due to similar adsorption mechanism on SWCNT-NH2. Opposite tendency was observed for SWCNT, DFN did not greatly affect adsorption of PCP and OP since they were very easily absorbable by sigma-sigma interaction.

Analysis of the thermo-mechanical deformations in a hot forging tool by numerical simulation

International Nuclear Information System (INIS)

L-Cancelos, R.; Varas, F.; Viéitez, I.; Martín, E.

2016-01-01

Although programs have been developed for the design of tools for hot forging, its design is still largely based on the experience of the tool maker. This obliges to build some test matrices and correct their errors to minimize distortions in the forged piece. This phase prior to mass production consumes time and material resources, which makes the final product more expensive. The forging tools are usually constituted by various parts made of different grades of steel, which in turn have different mechanical properties and therefore suffer different degrees of strain. Furthermore, the tools used in the hot forging are exposed to a thermal field that also induces strain or stress based on the degree of confinement of the piece. Therefore, the mechanical behaviour of the assembly is determined by the contact between the different pieces. The numerical simulation allows to analyse different configurations and anticipate possible defects before tool making, thus, reducing the costs of this preliminary phase. In order to improve the dimensional quality of the manufactured parts, the work presented here focuses on the application of a numerical model to a hot forging manufacturing process in order to predict the areas of the forging die subjected to large deformations. The thermo-mechanical model developed and implemented with free software (Code-Aster) includes the strains of thermal origin, strains during forge impact and contact effects. The numerical results are validated with experimental measurements in a tooling set that produces forged crankshafts for the automotive industry. The numerical results show good agreement with the experimental tests. Thereby, a very useful tool for the design of tooling sets for hot forging is achieved. (paper)

Analysis of the thermo-mechanical deformations in a hot forging tool by numerical simulation

Science.gov (United States)

L-Cancelos, R.; Varas, F.; Martín, E.; Viéitez, I.

2016-03-01

Although programs have been developed for the design of tools for hot forging, its design is still largely based on the experience of the tool maker. This obliges to build some test matrices and correct their errors to minimize distortions in the forged piece. This phase prior to mass production consumes time and material resources, which makes the final product more expensive. The forging tools are usually constituted by various parts made of different grades of steel, which in turn have different mechanical properties and therefore suffer different degrees of strain. Furthermore, the tools used in the hot forging are exposed to a thermal field that also induces strain or stress based on the degree of confinement of the piece. Therefore, the mechanical behaviour of the assembly is determined by the contact between the different pieces. The numerical simulation allows to analyse different configurations and anticipate possible defects before tool making, thus, reducing the costs of this preliminary phase. In order to improve the dimensional quality of the manufactured parts, the work presented here focuses on the application of a numerical model to a hot forging manufacturing process in order to predict the areas of the forging die subjected to large deformations. The thermo-mechanical model developed and implemented with free software (Code-Aster) includes the strains of thermal origin, strains during forge impact and contact effects. The numerical results are validated with experimental measurements in a tooling set that produces forged crankshafts for the automotive industry. The numerical results show good agreement with the experimental tests. Thereby, a very useful tool for the design of tooling sets for hot forging is achieved.

Implant-abutment connections on single crowns: a systematic review.

Science.gov (United States)

Ceruso, F M; Barnaba, P; Mazzoleni, S; Ottria, L; Gargari, M; Zuccon, A; Bruno, G; DI Fiore, A

2017-01-01

Different implant-abutment connections have been developed in the effort of reducing mechanical and biological failure. The most frequent complications are screw loosening, abutment or implant fracture and marginal bone loss due to overload and bacterial micro-leakage. Ideal connection should work as a one-piece implant avoiding the formation of a micro-gap at the implant-abutment interface. Different in vitro and in vivo researches have been published to compare the implant-abutment connections actually available: external hexagon, internal hexagon and conical finding different amount of micro-gap, micro-leakage and marginal bone loss. The aim of this article is to describe, according to the most recent literature, different kind of fixture-abutment connections and their clinical and mechanical advantages or disadvantages.

Accuracy of Single Periapical Radiography in Diagnosis of Horizontal Root Fracture

Directory of Open Access Journals (Sweden)

Fazlolah Soleymani Najafabadi

2012-02-01

Full Text Available Background and Aims: Radiographic examination is a necessary step in diagnosis of horizontal root fracture. The purpose of this study was to determine the sensitivity and specificity of single radiograph for detection of horizontal root fracture. Materials and Methods: In this analytical-descriptive study, 30 human freshly extracted teeth were used. Using a hammer and clamp, the teeth were divided into two sections accidentally and then sections were attached together by cyanoacrylate glue. Two radiographs were taken; with and without a piece of human mandibular bone. Afterward, radiographs were analyzed by three expert dentists using a slide show device. Results: The diagnostic sensitivity and specificity of single radiograph for detection of horizontal root fracture without bone was 100%, but in radiographs of teeth with bone was 82.7% and 100%, respectively. Conclusion: Based on the results of this study, in most cases, the horizontal root fractures can be detected by a single periapical radiograph.

Advanced mechanics from Euler's determinism to Arnold's chaos

CERN Document Server

Rajeev, S G

2013-01-01

Classical Mechanics is the oldest and best understood part of physics. This does not mean that it is cast in marble yet, a museum piece to be admired from a distance. Instead, mechanics continues to be an active area of research by physicists and mathematicians. Every few years, we need to re-evaluate the purpose of learning mechanics and look at old material in the light of modern developments. Once you have learned basic mechanics (Newton's laws, the solution of the Kepler problem) and quantum mechanics (the Schrodinger equation, hydrogen atom) it is time to go back and relearn classical mechanics in greater depth. It is the intent of this book to take you through the ancient (the original meaning of "classical") parts of the subject quickly: the ideas started by Euler and ending roughly with Poincare. We then take up the developments of twentieth century physics that have largely to do with chaos and discrete time evolution (the basis of numerical solutions).

Quality attributes and color characteristics in three-piece boneless hams.

Science.gov (United States)

McKeith, Russell O; Pringle, T Dean

2013-09-01

One hundred and fifty hams were selected on visual assessment of quality into normal (C) and two-tone (TT) groups. CIE LAB color and pH measurements were collected at the plant 48h postmortem on the gluteus medius (GM), gluteus profundus (GP), and rectus femoris (RF), and again at 72h on the semimembranosus (SM), biceps femoris (BF), semitendinosus (ST), and RF. Data were analyzed using GLM procedures of SAS, and correlations between color scores, pH, and drip loss were calculated. Plant and fabrication pH were lower (Phams compared with C. Muscles from TT hams had lower (Pcolor and pH are accurate predictors of pork quality attributes in the muscles of a three-piece boneless ham. Copyright © 2013 Elsevier Ltd. All rights reserved.

Comparison of thorough decontamination techniques on dismantled pieces of a PWR reactor

International Nuclear Information System (INIS)

Klein, M.; Rahier, A.; Mandoki, R.; Ponnet, M.

1998-01-01

The decontamination experience gained during the BR3 dismantling project is developed. This started with the full system decontamination of the primary loop and was followed by R and D on thorough decontamination projects. First, a wet abrasive installation has been installed and is now in operation for the thorough cleaning of metallic pieces of simple geometry. Afterwards, the chemical cerium process has been developed. The results of the regeneration with ozone and with electrochemistry are presented in detail. The ozone regeneration process has been selected for the industrial installation of which the construction is foreseen in 1998. (author)

Microstructural evolution and mechanical performance of resistance spot welded DP1000 steel with single and double pulse welding

NARCIS (Netherlands)

Chabok, Ali; van der Aa, Ellen; De Hosson, Jeff; Pei, Yutao T.

2017-01-01

Two welding schemes of single and double pulse were used for the resistance spot welding of DP1000 dual phase steel. The changes in the mechanical performance and variant pairing of martensite under two different welding conditions were scrutinized. It is demonstrated that, although both welds fail

Mechanics of Wood Machining

CERN Document Server

Csanády, Etele

2013-01-01

Wood is one of the most valuable materials for mankind, and since our earliest days wood materials have been widely used. Today we have modern woodworking machine and tools; however, the raw wood materials available are continuously declining. Therefore we are forced to use this precious material more economically, reducing waste wherever possible. This new textbook on the “Mechanics of Wood Machining” combines the quantitative, mathematical analysis of the mechanisms of wood processing with practical recommendations and solutions. Bringing together materials from many sources, the book contains new theoretical and experimental approaches and offers a clear and systematic overview of the theory of wood cutting, thermal loading in wood-cutting tools, dynamic behaviour of tool and work piece, optimum choice of operational parameters and energy consumption, the wear process of the tools, and the general regularities of wood surface roughness. Diagrams are provided for the quick estimation of various process ...

Simultaneous Measurement of Multiple Mechanical Properties of Single Cells Using AFM by Indentation and Vibration.

Science.gov (United States)

Zhang, Chuang; Shi, Jialin; Wang, Wenxue; Xi, Ning; Wang, Yuechao; Liu, Lianqing

2017-12-01

The mechanical properties of cells, which are the main characteristics determining their physical performance and physiological functions, have been actively studied in the fields of cytobiology and biomedical engineering and for the development of medicines. In this study, an indentation-vibration-based method is proposed to simultaneously measure the mechanical properties of cells in situ, including cellular mass (m), elasticity (k), and viscosity (c). The proposed measurement method is implemented based on the principle of forced vibration stimulated by simple harmonic force using an atomic force microscope (AFM) system integrated with a piezoelectric transducer as the substrate vibrator. The corresponding theoretical model containing the three mechanical properties is derived and used to perform simulations and calculations. Living and fixed human embryonic kidney 293 (HEK 293) cells were subjected to indentation and vibration to measure and compare their mechanical parameters and verify the proposed approach. The results that the fixed sample cells are more viscous and elastic than the living sample cells and the measured mechanical properties of cell are consistent within, but not outside of the central region of the cell, are in accordance with the previous studies. This work provides an approach to simultaneous measurement of the multiple mechanical properties of single cells using an integrated AFM system based on the principle force vibration and thickness-corrected Hertz model. This study should contribute to progress in biomedical engineering, cytobiology, medicine, early diagnosis, specific therapy and cell-powered robots.

RETURNED FOOT EXTERIOR CHORD BROOCHES MADE OF A SINGLE METAL PIECE (TYPE ALMGREN 158 RECENTLY DISCOVERED IN THE WESTERN PLAIN OF ROMANIA.

Directory of Open Access Journals (Sweden)

Vitalie Bârcă

2014-07-01

Full Text Available This study, without aiming at exhaustiveness, attempts, based on returned foot exterior chord brooches made of a single metal pieces (type Almgren 158 discovered in 2010 following the rescue archaeological excavations performed as a result of the construction of the Arad-Timişoara Highway, respectively section Arad-Seceani, in a series of Sarmatian graves of the cemetery investigated at Hunedoara Timișană, Șagu commune, Arad county, to analyse the brooches in this type discovered in the western territories of Romania.The author examines the four specimens at Hunedoara Timișană within a broader context and concludes that similar brooches in both the Barbarian and Roman environments, where they are imports, date mainly to the chronological interval comprised between the last two decades of the 2nd c. – early 4th c. AD (stages C1a-C2.The analysis of the graves in the cemetery showed that the graves where returned foot exterior chord brooches were found date sometime in the chronological interval comprised between the end of the 2nd c. AD and the third quarter of the 3rd c. AD. Moreover, the author notes that the distribution area of this brooch type is mainly the Barbarian world of German origin (the Przeworsk culture environment or that in constant contact with the latter. Based on the analysis of the distribution area of the Almgren 158 type brooches it was concluded they originate in the Przeworsk culture environment from where they disseminated in the neighbouring south and south-east cultural environments. Last but not least, the author reaches the conclusion that brooches of the type were assumed by the Sarmatians in the Pannonian Plain from the German populations (most likely the Vandals living in the northern vicinity of the area they inhabited. Another conclusion is that such returned foot exterior chord brooches are lacking from the north and north-west Pontic areas, including the Chernyakhov area. Finally, the author argues that

Free vibration analysis of single-walled boron nitride nanotubes based on a computational mechanics framework

Science.gov (United States)

Yan, J. W.; Tong, L. H.; Xiang, Ping

2017-12-01

Free vibration behaviors of single-walled boron nitride nanotubes are investigated using a computational mechanics approach. Tersoff-Brenner potential is used to reflect atomic interaction between boron and nitrogen atoms. The higher-order Cauchy-Born rule is employed to establish the constitutive relationship for single-walled boron nitride nanotubes on the basis of higher-order gradient continuum theory. It bridges the gaps between the nanoscale lattice structures with a continuum body. A mesh-free modeling framework is constructed, using the moving Kriging interpolation which automatically satisfies the higher-order continuity, to implement numerical simulation in order to match the higher-order constitutive model. In comparison with conventional atomistic simulation methods, the established atomistic-continuum multi-scale approach possesses advantages in tackling atomic structures with high-accuracy and high-efficiency. Free vibration characteristics of single-walled boron nitride nanotubes with different boundary conditions, tube chiralities, lengths and radii are examined in case studies. In this research, it is pointed out that a critical radius exists for the evaluation of fundamental vibration frequencies of boron nitride nanotubes; opposite trends can be observed prior to and beyond the critical radius. Simulation results are presented and discussed.

Mutation-Specific Mechanisms of Hyperactivation of Noonan Syndrome SOS Molecules Detected with Single-molecule Imaging in Living Cells.

Science.gov (United States)

Nakamura, Yuki; Umeki, Nobuhisa; Abe, Mitsuhiro; Sako, Yasushi

2017-10-26

Noonan syndrome (NS) is a congenital hereditary disorder associated with developmental and cardiac defects. Some patients with NS carry mutations in SOS, a guanine nucleotide exchange factor (GEF) for the small GTPase RAS. NS mutations have been identified not only in the GEF domain, but also in various domains of SOS, suggesting that multiple mechanisms disrupt SOS function. In this study, we examined three NS mutations in different domains of SOS to clarify the abnormality in its translocation to the plasma membrane, where SOS activates RAS. The association and dissociation kinetics between SOS tagged with a fluorescent protein and the living cell surface were observed in single molecules. All three mutants showed increased affinity for the plasma membrane, inducing excessive RAS signalling. However, the mechanisms by which their affinity was increased were specific to each mutant. Conformational disorder in the resting state, increased probability of a conformational change on the plasma membrane, and an increased association rate constant with the membrane receptor are the suggested mechanisms. These different properties cause the specific phenotypes of the mutants, which should be rescuable with different therapeutic strategies. Therefore, single-molecule kinetic analyses of living cells are useful for the pathological analysis of genetic diseases.

Low inductance diode design of the Proto 2 accelerator for imploding plasma loads

Science.gov (United States)

Hsing, W. W.; Coats, R.; McDaniel, D. H.; Spielman, R. B.

A new water transmission line convolute, single piece insulator, and double accelerator. The water transmission lines have a 5 cm gap to eliminate any water arcing. A two-dimensional magnetic field code was used to calculate the convolute inductance. An acrylic insulator was used as well as a single piece, laminated polycarbonate insulator. They have been successfully tested at over 90% of the Shipman criteria for classical insulator breakdown, although the laminations in the polycarbonate insulator failed after a few shots. The anode and cathode each have two pieces and are held together mechanically. The vacuum MITL tapers to a 3 mm minimum gap. The total inductance is 8.4 nH for gas puff loads and 7.8 nH for imploding foil loads. Out of a forward-going energy of 290 kJ, 175 kJ has been delivered past the insulator, and 100 kJ has been successfully delivered to the load.

Fuel Element Mechanical Design for CAREM-25 Reactor

International Nuclear Information System (INIS)

Estevez, Esteban; Markiewicz, Mario; Gerding, Jose

2000-01-01

The Fuel Element mechanical design and spider-control reactivity and security rods assembly for the CAREM-25 reactor is introduced. The CAREM-25 Fuel Element has a hexagonal cross section with 127 positions, in a triangular arrangement.There are 108 positions for the fuel rods while the guide tubes and instrumentation tube occupy the 19 remaining positions.From the structural point of view, the fuel element is being composed by a framework formed by the guides and instrumentation tubes, 4 spacer grids and the upper and lower coupling pieces.The spider is a plane piece, with a central body and six radial branches in T form, which has holes where the absorber rods are fitted.The central body ends in a joint in the upper side, which allows connect the assembly whit the reactor control mechanisms.The absorber rods are made of a neutron absorber material (Ag-In-Cd) hermetically closed in a stainless steel cladding. In this work are determined, in addition to the basic design, the operational conditions, the functional requirements to be satisfied and in agreement with those, the adopted criteria and limits to avoid systematics failure during normal operation conditions. The proposed program for the verification and evaluation of design is detailed.To consolidate the design, a prototype was manufactures, based on drawings and specifications needed for its construction

Single-molecule exploration of photoprotective mechanisms in light-harvesting complexes

Science.gov (United States)

Yang, Hsiang-Yu; Schlau-Cohen, Gabriela S.; Gwizdala, Michal; Krüger, Tjaart; Xu, Pengqi; Croce, Roberta; van Grondelle, Rienk; Moerner, W. E.

2015-03-01

Plants harvest sunlight by converting light energy to electron flow through the primary events in photosynthesis. One important question is how the light harvesting machinery adapts to fluctuating sunlight intensity. As a result of various regulatory processes, efficient light harvesting and photoprotection are balanced. Some of the biological steps in the photoprotective processes have been extensively studied and physiological regulatory factors have been identified. For example, the effect of lumen pH in changing carotenoid composition has been explored. However, the importance of photophysical dynamics in the initial light-harvesting steps and its relation to photoprotection remain poorly understood. Conformational and excited-state dynamics of multi-chromophore pigment-protein complexes are often difficult to study and limited information can be extracted from ensemble-averaged measurements. To address the problem, we use the Anti-Brownian ELectrokinetic (ABEL) trap to investigate the fluorescence from individual copies of light-harvesting complex II (LHCII), the primary antenna protein in higher plants, in a solution-phase environment. Perturbative surface immobilization or encapsulation schemes are avoided, and therefore the intrinsic dynamics and heterogeneity in the fluorescence of individual proteins are revealed. We perform simultaneous measurements of fluorescence intensity (brightness), excited-state lifetime, and emission spectrum of single trapped proteins. By analyzing the correlated changes between these observables, we identify forms of LHCII with different fluorescence intensities and excited-state lifetimes. The distinct forms may be associated with different energy dissipation mechanisms in the energy transfer chain. Changes of relative populations in response to pH and carotenoid composition are observed, which may extend our understanding of the molecular mechanisms of photoprotection.

Mechanical properties evaluation of single and hybrid composites polyester reinforced bamboo, PALF and coir fiber

Science.gov (United States)

Rihayat, T.; Suryani, S.; Fauzi, T.; Agusnar, H.; Wirjosentono, B.; Syafruddin; Helmi; Zulkifli; Alam, P. N.; Sami, M.

2018-03-01

This study aims to determine the composition fiber natural of bamboo, pineapple leaf and coir in single and hybrid composite to see the best characteristics of tensile strength and flexural test by using a Universal Testing Machine (UTM) and observe the effect on the microstructure of the composite through optical and scanning electron microscopy. Bamboo, Palf and coir have synthesis from natural fiber was used as reinforcement in polyester composite using hand lay up or a hot-compression moulding while filler:matrix was used (45%:55wt.%, 70%:30wt.% and 15%:85wt.%). From the variation of the volume fraction between filler and matrix show that mechanical properties of composites increased with increasing amount of filler in the matrix. This is evidenced by the high mechanical properties A:B:C/Ps in compositions 45%: 55wt.% 136 Mpa while flexural strength 93 N and good structure surface morphology. This research has produced a hybrid composite materials that have high mechanical properties and bending compared with conventional synthetic fibers and other materials.

Joining the Pieces: Using Concept Maps for Integrated Learning and Assessment in an Introductory Management Course

Science.gov (United States)

Connolly, Heather; Spiller, Dorothy

2016-01-01

This paper reports on and evaluates the use of concept mapping as a learning tool in a large first year Management course. The goal was to help students make personal sense of course learning and to build their understanding of links and relationships between key course ideas. Concept mapping was used for three summative assessment pieces,…

Energy Harvesting Research: The Road from Single Source to Multisource.

Science.gov (United States)

Bai, Yang; Jantunen, Heli; Juuti, Jari

2018-06-07

Energy harvesting technology may be considered an ultimate solution to replace batteries and provide a long-term power supply for wireless sensor networks. Looking back into its research history, individual energy harvesters for the conversion of single energy sources into electricity are developed first, followed by hybrid counterparts designed for use with multiple energy sources. Very recently, the concept of a truly multisource energy harvester built from only a single piece of material as the energy conversion component is proposed. This review, from the aspect of materials and device configurations, explains in detail a wide scope to give an overview of energy harvesting research. It covers single-source devices including solar, thermal, kinetic and other types of energy harvesters, hybrid energy harvesting configurations for both single and multiple energy sources and single material, and multisource energy harvesters. It also includes the energy conversion principles of photovoltaic, electromagnetic, piezoelectric, triboelectric, electrostatic, electrostrictive, thermoelectric, pyroelectric, magnetostrictive, and dielectric devices. This is one of the most comprehensive reviews conducted to date, focusing on the entire energy harvesting research scene and providing a guide to seeking deeper and more specific research references and resources from every corner of the scientific community. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Single-molecule FRET unveils induced-fit mechanism for substrate selectivity in flap endonuclease 1

KAUST Repository

Rashid, Fahad

2017-02-23

Human flap endonuclease 1 (FEN1) and related structure-specific 5\\'nucleases precisely identify and incise aberrant DNA structures during replication, repair and recombination to avoid genomic instability. Yet, it is unclear how the 5\\'nuclease mechanisms of DNA distortion and protein ordering robustly mediate efficient and accurate substrate recognition and catalytic selectivity. Here, single-molecule sub-millisecond and millisecond analyses of FEN1 reveal a protein-DNA induced-fit mechanism that efficiently verifies substrate and suppresses off-target cleavage. FEN1 sculpts DNA with diffusion-limited kinetics to test DNA substrate. This DNA distortion mutually \\'locks\\' protein and DNA conformation and enables substrate verification with extreme precision. Strikingly, FEN1 never misses cleavage of its cognate substrate while blocking probable formation of catalytically competent interactions with noncognate substrates and fostering their pre-incision dissociation. These findings establish FEN1 has practically perfect precision and that separate control of induced-fit substrate recognition sets up the catalytic selectivity of the nuclease active site for genome stability.

D-piece modifications of the hemiasterlin analog HTI-286 produce potent tubulin inhibitors.

Science.gov (United States)

Zask, Arie; Birnberg, Gary; Cheung, Katherine; Kaplan, Joshua; Niu, Chuan; Norton, Emily; Yamashita, Ayako; Beyer, Carl; Krishnamurthy, Girija; Greenberger, Lee M; Loganzo, Frank; Ayral-Kaloustian, Semiramis

2004-08-16

Modifications of the D-piece carboxylic acid group of the hemiasterlin analog HTI-286 gave tubulin inhibitors which were potent cytotoxic agents in taxol resistant cell lines expressing P-glycoprotein. Amides derived from proline had potency comparable to HTI-286. Reduction of the carboxylic acid to ketones and alcohols or its conversion to acidic heterocycles also gave potent analogs. Synthetic modifications of the carboxylic acid could be carried out selectively using a wide range of synthetic reagents. Proline analog 3 was found to be effective in a human xenograft model in athymic mice.

75 FR 4693 - New Postal Product

Science.gov (United States)

2010-01-29

... Post Group exceed six times the rate for the first ounce of a First-Class Mail letter. Id., para. (e... Dominant Products 1000 Market Dominant Product List First-Class Mail Single-Piece Letters/Postcards Bulk Letters/Postcards Flats Parcels Outbound Single-Piece First-Class Mail International Inbound Single-Piece...

Effect of cobalt on microstructural parameters and mechanical properties of Ni-base single crystal superalloys

International Nuclear Information System (INIS)

Suzuki, Takanobu; Imai, Hachiro; Yokokawa, Tadaharu; Kobayashi, Toshiharu; Koizumi, Yutaka; Harada, Hiroshi

2007-01-01

The alloying effect of Cobalt (Co) to microstructural parameters and mechanical properties, such as partitioning ratios of alloying elements and creep strength, of Re-bearing Ni-base single crystal superalloys have been investigated. The second generation single crystal superalloys, TMS-82+, Ni-7.8Co-4.9Cr-1.9Mo-8.7W-5.3Al-6.0Ta-2.4Re-0.1Hf, in mass% (8Co) was compared to a Co-free (0Co) and 15 mass% Co (15Co) alloy which had the same chemical composition as TMS-82+ except that Co was changed. It was shown that the partitioning ratios of alloying elements trend to k(=X γ /X' γ )=1, as the content of Co was increased. Furthermore, it was found that there was suitable content of Co for the creep strength under various temperature-stress conditions. (author)

Assembly Test of Elastic Averaging Technique to Improve Mechanical Alignment for Accelerating Structure Assemblies in CLIC

CERN Document Server

Huopana, J

2010-01-01

The CLIC (Compact LInear Collider) is being studied at CERN as a potential multi-TeV e+e- collider [1]. The manufacturing and assembly tolerances for the required RF-components are important for the final efficiency and for the operation of CLIC. The proper function of an accelerating structure is very sensitive to errors in shape and location of the accelerating cavity. This causes considerable issues in the field of mechanical design and manufacturing. Currently the design of the accelerating structures is a disk design. Alternatively it is possible to create the accelerating assembly from quadrants, which favour the mass manufacturing. The functional shape inside of the accelerating structure remains the same and a single assembly uses less parts. The alignment of these quadrants has been previously made kinematic by using steel pins or spheres to align the pieces together. This method proved to be a quite tedious and time consuming method of assembly. To limit the number of different error sources, a meth...

Failure of single electron descriptions of molecular orbital collision processes. [Electron promotion mechanism

Energy Technology Data Exchange (ETDEWEB)

Elston, S.B.

1978-01-01

Inner-shell excitation occurring in low and moderate (keV range) energy collisions between light atomic and ionic systems is frequently describable in terms of molecular promotion mechanisms, which were extensively explored both theoretically and experimentally. The bulk of such studies have concentrated on processes understandable through the use of single- and independent-electron models. Nonetheless, it is possible to find cases of inner-shell excitation in relatively simple collision systems which involve nearly simultaneous multiple-electron transitions and transitions induced by inherently two-electron interactions. Evidence for these many- and nonindependent-electron phenomena in inner-shell excitation processes and the importance of considering such effects in the interpretation of collisionally induced excitation spectra is discussed. 13 references.

Exposure to texture of foods for 8-month-old infants : Does the size of the pieces matter?

NARCIS (Netherlands)

da Costa, Saakje P.; Remijn, Lianne; Weenen, Hugo; Vereijken, Carel; van der Schans, Cees

2017-01-01

This study examined the effect of meals varying in amount, size, and hardness of food pieces on the development of the chewing capabilities of 8-month-old infants. The study also examined changes in shivering, gagging, coughing, choking, and their ability to eat from a spoon. In an in-home setting

Archaeological analogous and industrials for deep storage: study of the archaeological metallic piece; Analogos arqueologicos e industriales para almacenamientos profundos: estudio de piezas arqueologicas metalicas

Energy Technology Data Exchange (ETDEWEB)

Criado Portal, A J; Martinez Garcia, J A; Calabres Molina, R; Garcia abajo, A; Penco Valenzuela, F; Lecanda Esteban, J A; Garcia Bartual, M; Jimenez Gonzalez, J M; Bravo Munoz, E; Rodriguez Lobo, L M; Fernandez Cascos, T; Fernandes Cordero, O; Montero Ruiz, I

2000-07-01

The aim of present research is to obtain information about archaeological analogous of iron and steel, useful for the model of deep geological repository (AGP). The analogous examined have remained buried between 1400 and 2400 years, in very assorted geochemical environments. The extraction of the archaeological pieces has been accomplished according to normalised protocols, trying to carry to the laboratory so the piece as its burial environment, avoiding all possible pollution. Trying to the archaeological analogous could provide valuable information to the AGP model, the study has been directed to related the physical-chemical characteristics of the terrain respect to the deterioration of the archaeological metallic piece. The geology of the surrounding terrain to the archaeological deposit, the geomorphological study of the terrain and data from the analysis of ground: pH, wetness, porosity, organic matter contents, bacteria presence, sulphates, carbonates, chlorides, etc., have allowed to explain the physical-chemical phenomena suffered by the archaeological iron and steel pieces. Also, an exhaustive study of the archaeological piece has been accomplished, concerning the microstructure of the corrosion layer and of the not deteriorated metallic rest. Obtained information concerns different items, such as corrosion velocity and formations of oxide layers, diffusion of chemical elements from the corrosion layer to the metal and viceversa, and structural changes in oxide layers and in the metallic remains by structural ageing. Obtained data have allowed to develop a mathematical model for calculation of corrosion velocity in buried iron and steels, based on physical-chemical variables of grounds, chemical composition and thermomechanical treatment given to the metal during its manufacture. (Author)

Preparation and applications of mechanically exfoliated single-layer and multilayer MoS₂ and WSe₂ nanosheets.

Science.gov (United States)

Li, Hai; Wu, Jumiati; Yin, Zongyou; Zhang, Hua

2014-04-15

Although great progress has been achieved in the study of graphene, the small current ON/OFF ratio in graphene-based field-effect transistors (FETs) limits its application in the fields of conventional transistors or logic circuits for low-power electronic switching. Recently, layered transition metal dichalcogenide (TMD) materials, especially MoS2, have attracted increasing attention. In contrast to its bulk material with an indirect band gap, a single-layer (1L) MoS2 nanosheet is a semiconductor with a direct band gap of ~1.8 eV, which makes it a promising candidate for optoelectronic applications due to the enhancement of photoluminescence and high current ON/OFF ratio. Compared with TMD nanosheets prepared by chemical vapor deposition and liquid exfoliation, mechanically exfoliated ones possess pristine, clean, and high-quality structures, which are suitable for the fundamental study and potential applications based on their intrinsic thickness-dependent properties. In this Account, we summarize our recent research on the preparation, characterization, and applications of 1L and multilayer MoS2 and WSe2 nanosheets produced by mechanical exfoliation. During the preparation of nanosheets, we proposed a simple optical identification method to distinguish 1L and multilayer MoS2 and WSe2 nanosheets on a Si substrate coated with 90 and 300 nm SiO2. In addition, we used Raman spectroscopy to characterize mechanically exfoliated 1L and multilayer WSe2 nanosheets. For the first time, a new Raman peak at 308 cm(-1) was observed in the spectra of WSe2 nanosheets except for the 1L WSe2 nanosheet. Importantly, we found that the 1L WSe2 nanosheet is very sensitive to the laser power during characterization. The high power laser-induced local oxidation of WSe2 nanosheets and single crystals was monitored by Raman spectroscopy and atomic force microscopy (AFM). Hexagonal and monoclinic structured WO3 thin films were obtained from the local oxidization of single- to triple

Clinical Performance of One-Piece, Screw-Retained Implant Crowns Based on Hand-Veneered CAD/CAM Zirconia Abutments After a Mean Follow-up Period of 2.3 Years.

Science.gov (United States)

Schnider, Nicole; Forrer, Fiona Alena; Brägger, Urs; Hicklin, Stefan Paul

The aim of this study was to evaluate the clinical performance of one-piece, screw-retained implant crowns based on hand-veneered computer-aided design/computer-aided manufacture (CAD/CAM) zirconium dioxide abutments with a crossfit connection at least 1 year after insertion of the crown. Consecutive patients who had received at least one Straumann bone level implant and one-piece, screw-retained implant crowns fabricated with CARES zirconium dioxide abutments were reexamined. Patient satisfaction, occlusal and peri-implant parameters, mechanical and biologic complications, radiologic parameters, and esthetics were recorded. A total of 50 implant crowns in the anterior and premolar region were examined in 41 patients. The follow-up period of the definitive reconstructions ranged from 1.1 to 3.8 years. No technical and no biologic complications had occurred. At the reexamination, 100% of the implants and reconstructions were in situ. Radiographic evaluation revealed a mean distance from the implant shoulder to the first visible bone-to-implant contact of 0.06 mm at the follow-up examination. Screw-retained crowns based on veneered CAD/CAM zirconium dioxide abutments with a crossfit connection seem to be a promising way to replace missing teeth in the anterior and premolar region. In the short term, neither failures of components nor complications were noted, and the clinical and radiographic data revealed stable hard and soft tissue conditions.

A molecular-mechanics based finite element model for strength prediction of single wall carbon nanotubes

International Nuclear Information System (INIS)

Meo, M.; Rossi, M.

2007-01-01

The aim of this work was to develop a finite element model based on molecular mechanics to predict the ultimate strength and strain of single wallet carbon nanotubes (SWCNT). The interactions between atoms was modelled by combining the use of non-linear elastic and torsional elastic spring. In particular, with this approach, it was tried to combine the molecular mechanics approach with finite element method without providing any not-physical data on the interactions between the carbon atoms, i.e. the CC-bond inertia moment or Young's modulus definition. Mechanical properties as Young's modulus, ultimate strength and strain for several CNTs were calculated. Further, a stress-strain curve for large deformation (up to 70%) is reported for a nanotube Zig-Zag (9,0). The results showed that good agreement with the experimental and numerical results of several authors was obtained. A comparison of the mechanical properties of nanotubes with same diameter and different chirality was carried out. Finally, the influence of the presence of defects on the strength and strain of a SWNT was also evaluated. In particular, the stress-strain curve a nanotube with one-vacancy defect was evaluated and compared with the curve of a pristine one, showing a reduction of the ultimate strength and strain for the defected nanotube. The FE model proposed demonstrate to be a reliable tool to simulate mechanical behaviour of carbon nanotubes both in the linear elastic field and the non-linear elastic field

Seeking Emancipation from Gender Regulation: Reflections on Home space for a Black Woman Academic/ Single Mother

Directory of Open Access Journals (Sweden)

Lisa William-­White

2012-06-01

Full Text Available Using the work of Judith Butler on gender regulation, Black Feminist Thought (BFT, and autobiographic storytelling, this piece illustrates how essentialist notions of gender, and discourses related to gender create conflict in shaping identity construction for a Black woman academic and single mother (BWA/SM in the United States. This piece reveals complex gendered and racialized tropes related to notions of motherhood and womanhood, particularly within the author’s own family. Included here is how the author attempts to transcend these complexities in her quest for self­definition and self­actualization, unbridled by gender norms. Yet, race, gender and parental status are significant intersecting categories in identity construction, andinherent in the constructions are hegemonic discourses with which the author continues to grapple. Consequently, the struggle to transcend these forces is further complicated by the limited representation of Black women in the US academy, and by the types of academic work where they find themselves typically situated.

Exact results in nonequilibrium statistical mechanics: Formalism and applications in chemical kinetics and single-molecule free energy estimation

Science.gov (United States)

Adib, Artur B.

In the last two decades or so, a collection of results in nonequilibrium statistical mechanics that departs from the traditional near-equilibrium framework introduced by Lars Onsager in 1931 has been derived, yielding new fundamental insights into far-from-equilibrium processes in general. Apart from offering a more quantitative statement of the second law of thermodynamics, some of these results---typified by the so-called "Jarzynski equality"---have also offered novel means of estimating equilibrium quantities from nonequilibrium processes, such as free energy differences from single-molecule "pulling" experiments. This thesis contributes to such efforts by offering three novel results in nonequilibrium statistical mechanics: (a) The entropic analog of the Jarzynski equality; (b) A methodology for estimating free energies from "clamp-and-release" nonequilibrium processes; and (c) A directly measurable symmetry relation in chemical kinetics similar to (but more general than) chemical detailed balance. These results share in common the feature of remaining valid outside Onsager's near-equilibrium regime, and bear direct applicability in protein folding kinetics as well as in single-molecule free energy estimation.

Material removal mechanisms in electrochemical-mechanical polishing of tantalum

International Nuclear Information System (INIS)

Gao, F.; Liang, H.

2009-01-01

Material removal mechanisms in tantalum chemical-mechanical polishing (CMP) and electrochemical-mechanical polishing (ECMP) were investigated using the single frequency electrochemical impedance spectroscopy (EIS). Through measuring the impedance of the tantalum surface, the single frequency EIS scan made it possible to observe the CMP and ECMP processes in situ. The impedance results presented competing mechanisms of removal and formation of a surface oxide layer of tantalum. Analysis indicated that the thickness of the oxide layer formed during polishing was related to the mechanical power correlated to the friction force and the rotating speed. Furthermore, the rate of growth and removal of the oxide film was a function of the mechanical power. This understanding is beneficial for optimization of CMP and ECMP processes.

Field emission mechanism from a single-layer ultra-thin semiconductor film cathode

International Nuclear Information System (INIS)

Duan Zhiqiang; Wang Ruzhi; Yuan Ruiyang; Yang Wei; Wang Bo; Yan Hui

2007-01-01

Field emission (FE) from a single-layer ultra-thin semiconductor film cathode (SUSC) on a metal substrate has been investigated theoretically. The self-consistent quantum FE model is developed by synthetically considering the energy band bending and electron scattering. As a typical example, we calculate the FE properties of ultra-thin AlN film with an adjustable film thickness from 1 to 10 nm. The calculated results show that the FE characteristic is evidently modulated by varying the film thickness, and there is an optimum thickness of about 3 nm. Furthermore, a four-step FE mechanism is suggested such that the distinct FE current of a SUSC is rooted in the thickness sensitivity of its quantum structure, and the optimum FE properties of the SUSC should be attributed to the change in the effective potential combined with the attenuation of electron scattering

Single-vesicle imaging reveals different transport mechanisms between glutamatergic and GABAergic vesicles.

Science.gov (United States)

Farsi, Zohreh; Preobraschenski, Julia; van den Bogaart, Geert; Riedel, Dietmar; Jahn, Reinhard; Woehler, Andrew

2016-02-26

Synaptic transmission is mediated by the release of neurotransmitters, which involves exo-endocytotic cycling of synaptic vesicles. To maintain synaptic function, synaptic vesicles are refilled with thousands of neurotransmitter molecules within seconds after endocytosis, using the energy provided by an electrochemical proton gradient. However, it is unclear how transmitter molecules carrying different net charges can be efficiently sequestered while maintaining charge neutrality and osmotic balance. We used single-vesicle imaging to monitor pH and electrical gradients and directly showed different uptake mechanisms for glutamate and γ-aminobutyric acid (GABA) operating in parallel. In contrast to glutamate, GABA was exchanged for protons, with no other ions participating in the transport cycle. Thus, only a few components are needed to guarantee reliable vesicle filling with different neurotransmitters. Copyright © 2016, American Association for the Advancement of Science.

Supercharged two-cycle engines employing novel single element reciprocating shuttle inlet valve mechanisms and with a variable compression ratio

Science.gov (United States)

Wiesen, Bernard (Inventor)

2008-01-01

This invention relates to novel reciprocating shuttle inlet valves, effective with every type of two-cycle engine, from small high-speed single cylinder model engines, to large low-speed multiple cylinder engines, employing spark or compression ignition. Also permitting the elimination of out-of-phase piston arrangements to control scavenging and supercharging of opposed-piston engines. The reciprocating shuttle inlet valve (32) and its operating mechanism (34) is constructed as a single and simple uncomplicated member, in combination with the lost-motion abutments, (46) and (48), formed in a piston skirt, obviating the need for any complex mechanisms or auxiliary drives, unaffected by heat, friction, wear or inertial forces. The reciprocating shuttle inlet valve retains the simplicity and advantages of two-cycle engines, while permitting an increase in volumetric efficiency and performance, thereby increasing the range of usefulness of two-cycle engines into many areas that are now dominated by the four-cycle engine.

Mechanism of single atom switch on silicon

DEFF Research Database (Denmark)

Quaade, Ulrich; Stokbro, Kurt; Thirstrup, C.

1998-01-01

We demonstrate single atom switch on silicon which operates by displacement of a hydrogen atom on the silicon (100) surface at room temperature. We find two principal effects by which the switch is controlled: a pronounced maximum of the switching probability as function of sample bias...

A study of eukaryotic response mechanisms to atmospheric pressure cold plasma by using Saccharomyces cerevisiae single gene mutants

International Nuclear Information System (INIS)

Feng Hongqing; Wang Ruixue; Sun Peng; Wu Haiyan; Liu Qi; Li Fangting; Fang Jing; Zhang Jue; Zhu Weidong

2010-01-01

The mechanisms of eukaryotic cell response to cold plasma are studied. A series of single gene mutants of eukaryotic model organism Saccharomyces cerevisiae are used to compare their sensitivity to plasma treatment with the wild type. We examined 12 mutants in the oxidative stress pathway and the cell cycle pathway, in which 8 are found to be hypersensitive to plasma processing. The mutated genes' roles in the two pathways are analyzed to understand the biological response mechanisms of plasma treatment. The results demonstrate that genes from both pathways are needed for the eukaryotic cells to survive the complex plasma treatment.

The measurement problem in quantum mechanics: approximation to the phenomenon of decoherence by operational identities

International Nuclear Information System (INIS)

Usera, J.I.

1996-01-01

An approach based on bits and pieces of standard wisdom plus and operational quantum mechanical identity deduced by the author is presented here in order to convey arguments concerning the quantum theory of measurement and which betray a flavor against completive claims for quantum mechanics. Special emphasis is put on the phenomenon of decoherence. This phenomenon (which is experimentally verifiable) finds natural room within the formalism while the wave function collapse (which is not) is precluded. (Author)

The RNA silencing pathway: the bits and pieces that matter.

Directory of Open Access Journals (Sweden)

2005-07-01

Full Text Available Cellular pathways are generally proposed on the basis of available experimental knowledge. The proposed pathways, however, may be inadequate to describe the phenomena they are supposed to explain. For instance, by means of concise mathematical models we are able to reveal shortcomings in the current description of the pathway of RNA silencing. The silencing pathway operates by cleaving siRNAs from dsRNA. siRNAs can associate with RISC, leading to the degradation of the target mRNA. We propose and analyze a few small extensions to the pathway: a siRNA degrading RNase, primed amplification of aberrant RNA pieces, and cooperation between aberrant RNA to trigger amplification. These extensions allow for a consistent explanation for various types of silencing phenomena, such as virus induced silencing, transgene and transposon induced silencing, and avoidance of self-reactivity, as well as for differences found between species groups.

Numerical Simulation of a Grinding Process Model for the Spatial Work-pieces: Development of Modeling Techniques

Directory of Open Access Journals (Sweden)

S. A. Voronov

2015-01-01

Full Text Available The article presents a literature review in simulation of grinding processes. It takes into consideration the statistical, energy based, and imitation approaches to simulation of grinding forces. Main stages of interaction between abrasive grains and machined surface are shown. The article describes main approaches to the geometry modeling of forming new surfaces when grinding. The review of approaches to the chip and pile up effect numerical modeling is shown. Advantages and disadvantages of grain-to-surface interaction by means of finite element method and molecular dynamics method are considered. The article points out that it is necessary to take into consideration the system dynamics and its effect on the finished surface. Structure of the complex imitation model of grinding process dynamics for flexible work-pieces with spatial surface geometry is proposed from the literature review. The proposed model of spatial grinding includes the model of work-piece dynamics, model of grinding wheel dynamics, phenomenological model of grinding forces based on 3D geometry modeling algorithm. Model gives the following results for spatial grinding process: vibration of machining part and grinding wheel, machined surface geometry, static deflection of the surface and grinding forces under various cutting conditions.

85,000-GPM, single-stage, single-suction LMFBR intermediate centrifugal pump

International Nuclear Information System (INIS)

Fair, C.E.; Cook, M.E.; Huber, K.A.; Rohde, R.

1983-01-01

The mechanical and hydraulic design features of the 85,000-gpm, single-stage, single-suction pump test article, which is designed to circulate liquid-sodium coolant in the intermediate heat-transport system of a Large-Scale Liquid Metal Fast Breeder Reactor (LS-LMFBR), are described. The design and analytical considerations used to satisfy the pump performance and operability requirements are presented. The validation of pump hydraulic performance using a hydraulic scale-model pump is discussed, as is the featute test for the mechanical-shaft seal system

Early Loading of Single-Piece Implant for Partially Edentulous Posterior Arch: A Prospective One-Year Case Report

Directory of Open Access Journals (Sweden)

Amol Beldar

2013-01-01

Full Text Available Implant therapy is now well established, and there is an increasing need for shorter rehabilitation time. Original prerequisites of osseointegration have been reassessed to satisfy continuously increasing patient's expectation of reduced treatment time, improved esthetics, and increased comfort. Shorter healing time may be appropriate in some circumstances, and examples of early loading have been reported in animal and human studies. However, to date there are insufficient data to determine a universally acceptable opinion on early loading of implants for single-tooth replacement. This case report involves early loading, combined with construction of a restoration, inserted directly after 6 weeks of implant surgery and followup of one year.

Single-Molecule Titration in a Protein Nanoreactor Reveals the Protonation/Deprotonation Mechanism of a C:C Mismatch in DNA.

Science.gov (United States)

Ren, Hang; Cheyne, Cameron G; Fleming, Aaron M; Burrows, Cynthia J; White, Henry S

2018-04-18

Measurement of single-molecule reactions can elucidate microscopic mechanisms that are often hidden from ensemble analysis. Herein, we report the acid-base titration of a single DNA duplex confined within the wild-type α-hemolysin (α-HL) nanopore for up to 3 h, while monitoring the ionic current through the nanopore. Modulation between two states in the current-time trace for duplexes containing the C:C mismatch in proximity to the latch constriction of α-HL is attributed to the base flipping of the C:C mismatch. As the pH is lowered, the rate for the C:C mismatch to flip from the intra-helical state to the extra-helical state ( k intra-extra ) decreases, while the rate for base flipping from the extra-helical state to the intra-helical state ( k extra-intra ) remains unchanged. Both k intra-extra and k extra-intra are on the order of 1 × 10 -2 s -1 to 1 × 10 -1 s -1 and remain stable over the time scale of the measurement (several hours). Analysis of the pH-dependent kinetics of base flipping using a hidden Markov kinetic model demonstrates that protonation/deprotonation occurs while the base pair is in the intra-helical state. We also demonstrate that the rate of protonation is limited by transport of H + into the α-HL nanopore. Single-molecule kinetic isotope experiments exhibit a large kinetic isotope effect (KIE) for k intra-extra ( k H / k D ≈ 5) but a limited KIE for k extra-intra ( k H / k D ≈ 1.3), supporting our model. Our experiments correspond to the longest single-molecule measurements performed using a nanopore, and demonstrate its application in interrogating mechanisms of single-molecule reactions in confined geometries.

Two-piece impression procedure for implant-retained orbital prostheses.

Science.gov (United States)

Ozcelik, Tuncer Burak; Yilmaz, Burak

2012-01-01

Obtaining an accurate impression of facial tissues with undercuts and extraoral implants has always been a challenge for both clinicians and patients. This report describes a three-step, two-piece technique that enables an accurate and comfortable impression of undercut tissues and extraoral implants in an orbital defect. An impression of the basal tissue surface of the defect area was made using a medium-body polyether impression material followed by an impression of the entire face of the patient made with a polyvinyl siloxane (PVS) impression material. First, the PVS impression material was removed; second, the impression posts were removed from the magnets; and third, the polyether impression was removed from the defect. The impression posts were attached to the implant analogs and placed in the negative spaces in the polyether impression. The polyether impression, which carries the implant analogs and impression posts, was placed in the PVS impression through the negative spaces. This technique minimizes trauma to the soft tissues and implants during impression making and also does not require additional materials.

Dynamic Modeling and Nonlinear Position Control of a Quadruped Robot with Theo Jansen Linkage Mechanisms and a Single Actuator

Directory of Open Access Journals (Sweden)

Shunsuke Nansai

2015-01-01

Full Text Available The Theo Jansen mechanism is gaining widespread popularity among the legged robotics community due to its scalable design, energy efficiency, low payload-to-machine-load ratio, bioinspired locomotion, and deterministic foot trajectory. In this paper, we perform for the first time the dynamic modeling and analysis on a four-legged robot driven by a single actuator and composed of Theo Jansen mechanisms. The projection method is applied to derive the equations of motion of this complex mechanical system and a position control strategy based on energy is proposed. Numerical simulations validate the efficacy of the designed controller, thus setting a theoretical basis for further investigations on Theo Jansen based quadruped robots.

Influence of cobalt, tantalum, and tungsten on the microstructure and mechanical properties of superalloy single crystals

International Nuclear Information System (INIS)

Nathal, M.V.; Ebert, L.J.

1982-01-01

The influence of Co, Ta, and W on the microstructure and mechanical properties of nickel base super-alloy single crystals was investigated. A matrix of alloys was based on Mar-M 247 stripped of C, B, Zr, and Hf. The microstructures of the alloys were examined using optical and electron microscopy, phase extraction, X-ray diffraction, and differential thermal analysis. Tensile and creep-rupture tests were performed at 1000 C. An increase in tensile and creep strength resulted when Co was removed from alloys containing high refractory metal contents, but Co effects were negligible for alloys with lower refractory metal levels. In the composition range studied, W was more effective than Ta in increasing the creep resistance. The mechanical properties are discussed in relation to the microstructures of the alloys

Influence of cobalt, tantalum, and tungsten on the microstructure and mechanical properties of superalloy single crystals

Science.gov (United States)

Nathal, M. V.; Ebert, L. J.

1982-01-01

The influence of Co, Ta, and W on the microstructure and mechanical properties of nickel base super-alloy single crystals was investigated. A matrix of alloys was based on Mar-M 247 stripped of C, B, Zr, and Hf. The microstructures of the alloys were examined using optical and electron microscopy, phase extraction, X-ray diffraction, and differential thermal analysis. Tensile and creep-rupture tests were performed at 1000 C. An increase in tensile and creep strength resulted when Co was removed from alloys containing high refractory metal contents, but Co effects were negligible for alloys with lower refractory metal levels. In the composition range studied, W was more effective than Ta in increasing the creep resistance. The mechanical properties are discussed in relation to the microstructures of the alloys.

Optical Absorption and Emission Mechanisms of Single Defects in Hexagonal Boron Nitride

Science.gov (United States)

Jungwirth, Nicholas R.; Fuchs, Gregory D.

2017-08-01

We investigate the polarization selection rules of sharp zero-phonon lines (ZPLs) from isolated defects in hexagonal boron nitride (HBN) and compare our findings with the predictions of a Huang-Rhys model involving two electronic states. Our survey, which spans the spectral range ˜550 - 740 nm , reveals that, in disagreement with a two-level model, the absorption and emission dipoles are often misaligned. We relate the dipole misalignment angle (Δ θ ) of a ZPL to its energy shift from the excitation energy (Δ E ) and find that Δ θ ≈0 ° when Δ E corresponds to an allowed HBN phonon frequency and that 0 ° ≤Δ θ ≤90 ° when Δ E exceeds the maximum allowed HBN phonon frequency. Consequently, a two-level Huang-Rhys model succeeds at describing excitations mediated by the creation of one optical phonon but fails at describing excitations that require the creation of multiple phonons. We propose that direct excitations requiring the creation of multiple phonons are inefficient due to the low Huang-Rhys factors in HBN and that these ZPLs are instead excited indirectly via an intermediate electronic state. This hypothesis is corroborated by polarization measurements of an individual ZPL excited with two distinct wavelengths that indicate a single ZPL may be excited by multiple mechanisms. These findings provide new insight on the nature of the optical cycle of novel defect-based single-photon sources in HBN.

Mechanical energy losses in plastically deformed and electron plus neutron irradiated high purity single crystalline molybdenum at elevated temperatures

Energy Technology Data Exchange (ETDEWEB)

Zelada, Griselda I. [Laboratorio de Materiales, Escuela de Ingenieria Electrica, Facultad de Ciencias Exactas, Ingenieria y Agrimensura, Universidad Nacional de Rosario, Avda. Pellegrini 250, 2000 Rosario (Argentina); Lambri, Osvaldo Agustin [Laboratorio de Materiales, Escuela de Ingenieria Electrica, Facultad de Ciencias Exactas, Ingenieria y Agrimensura, Universidad Nacional de Rosario, Avda. Pellegrini 250, 2000 Rosario (Argentina); Instituto de Fisica Rosario - CONICET, Member of the CONICET& #x27; s Research Staff, Avda. Pellegrini 250, 2000 Rosario (Argentina); Bozzano, Patricia B. [Laboratorio de Microscopia Electronica, Unidad de Actividad Materiales, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica, Avda. Gral. Paz 1499, 1650 San Martin (Argentina); Garcia, Jose Angel [Departamento de Fisica Aplicada II, Facultad de Ciencias y Tecnologia, Universidad del Pais Vasco, Apdo. 644, 48080 Bilbao, Pais Vasco (Spain)

2012-10-15

Mechanical spectroscopy (MS) and transmission electron microscopy (TEM) studies have been performed in plastically deformed and electron plus neutron irradiated high purity single crystalline molybdenum, oriented for single slip, in order to study the dislocation dynamics in the temperature range within one third of the melting temperature. A damping peak related to the interaction of dislocation lines with both prismatic loops and tangles of dislocations was found. The peak temperature ranges between 900 and 1050 K, for an oscillating frequency of about 1 Hz. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Neuromuscular Control Mechanisms During Single-Leg Jump Landing in Subacute Ankle Sprain Patients: A Case Control Study.

Science.gov (United States)

Allet, Lara; Zumstein, Franziska; Eichelberger, Patric; Armand, Stéphane; Punt, Ilona M

2017-03-01

Optimal neuromuscular control mechanisms are essential for preparing, maintaining, and restoring functional joint stability during jump landing and to prevent ankle injuries. In subacute ankle sprain patients, neither muscle activity nor kinematics during jump landing has previously been assessed. To compare neuromuscular control mechanisms and kinematics between subacute ankle sprain patients and healthy persons before and during the initial contact phase of a 25-cm single-leg jump. Case-control study. University hospital. Fifteen patients with grade I or II acute ankle sprains were followed up after 4 weeks of conservative management not involving physical therapy. Subjects performed alternately 3 single-leg forward jumps of 25 cm (toe-to-heel distance) barefoot. Their results were compared with the data of 15 healthy subjects. Electromyographic (EMG) activity of the musculus (m.) gastrocnemius lateralis, m. tibialis anterior, and m. peroneus longus as well as kinematics for ankle, knee, and hip joint were recorded for pre-initial contact (IC) phase, post-initial contact phase, and reflex-induced phase. The results showed that EMG activity of the 3 muscles did not differ between ankle sprain patients (n = 15) and healthy persons (n = 15) for any of the analyzed time intervals (all P > .05). However, during the pre-IC phase, ankle sprain patients presented less plantar flexion, as well as during the post-IC phase after jump landing, compared to healthy persons (P ankle joint can lead to neuromuscular control mechanism disturbances through which functional instability might arise. III. Copyright © 2017 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Information Fields Navigation with Piece-Wise Polynomial Approximation for High-Performance OFDM in WSNs

Directory of Open Access Journals (Sweden)

Wei Wei

2013-01-01

Full Text Available Since Wireless sensor networks (WSNs are dramatically being arranged in mission-critical applications,it changes into necessary that we consider application requirements in Internet of Things. We try to use WSNs to assist information query and navigation within a practical parking spaces environment. Integrated with high-performance OFDM by piece-wise polynomial approximation, we present a new method that is based on a diffusion equation and a position equation to accomplish the navigation process conveniently and efficiently. From the point of view of theoretical analysis, our jobs hold the lower constraint condition and several inappropriate navigation can be amended. Information diffusion and potential field are introduced to reach the goal of accurate navigation and gradient descent method is applied in the algorithm. Formula derivations and simulations manifest that the method facilitates the solution of typical sensor network configuration information navigation. Concurrently, we also treat channel estimation and ICI mitigation for very high mobility OFDM systems, and the communication is between a BS and mobile target at a terrible scenario. The scheme proposed here combines the piece-wise polynomial expansion to approximate timevariations of multipath channels. Two near symbols are applied to estimate the first-and second-order parameters. So as to improve the estimation accuracy and mitigate the ICI caused by pilot-aided estimation, the multipath channel parameters were reestimated in timedomain employing the decided OFDM symbol. Simulation results show that this method would improve system performance in a complex environment.

DNA gyrase with a single catalytic tyrosine can catalyze DNA supercoiling by a nicking-closing mechanism

Science.gov (United States)

Gubaev, Airat; Weidlich, Daniela; Klostermeier, Dagmar

2016-01-01

The topological state of DNA is important for replication, recombination and transcription, and is regulated in vivo by DNA topoisomerases. Gyrase introduces negative supercoils into DNA at the expense of ATP hydrolysis. It is the accepted view that gyrase achieves supercoiling by a strand passage mechanism, in which double-stranded DNA is cleaved, and a second double-stranded segment is passed through the gap, converting a positive DNA node into a negative node. We show here that gyrase with only one catalytic tyrosine that cleaves a single strand of its DNA substrate can catalyze DNA supercoiling without strand passage. We propose an alternative mechanism for DNA supercoiling via nicking and closing of DNA that involves trapping, segregation and relaxation of two positive supercoils. In contrast to DNA supercoiling, ATP-dependent relaxation and decatenation of DNA by gyrase lacking the C-terminal domains require both tyrosines and strand passage. Our results point towards mechanistic plasticity of gyrase and might pave the way for finding novel and specific mechanism-based gyrase inhibitors. PMID:27557712

Testing and Modeling of Mechanical Characteristics of Resistance Welding Machines

DEFF Research Database (Denmark)

Wu, Pei; Zhang, Wenqi; Bay, Niels

2003-01-01

for both upper and lower electrode systems. This has laid a foundation for modeling the welding process and selecting the welding parameters considering the machine factors. The method is straightforward and easy to be applied in industry since the whole procedure is based on tests with no requirements......The dynamic mechanical response of resistance welding machine is very important to the weld quality in resistance welding especially in projection welding when collapse or deformation of work piece occurs. It is mainly governed by the mechanical parameters of machine. In this paper, a mathematical...... model for characterizing the dynamic mechanical responses of machine and a special test set-up called breaking test set-up are developed. Based on the model and the test results, the mechanical parameters of machine are determined, including the equivalent mass, damping coefficient, and stiffness...

Sc2C2@D3h(14246)-C74: A Missing Piece of the Clusterfullerene Puzzle.

Science.gov (United States)

Wang, Yaofeng; Tang, Qiangqiang; Feng, Lai; Chen, Ning

2017-02-20

Clusterfullerenes with variable carbon cages have been extensively studied in recent years. However, despite all these efforts, C 74 cage-based clusterfullerene remains a missing piece of the puzzle. Herein, we show that single-crystal X-ray crystallographic analysis unambiguously assigns the previously reported dimetallofullerene Sc 2 @C 76 to a novel carbide clusterfullerene, Sc 2 C 2 @D 3h (14246)-C 74 , the first experimentally proven clusterfullerene with a C 74 cage. In addition, Sc 2 C 2 @D 3h (14246)-C 74 was charaterized by mass spectrometry, ultraviolet-visible-near-infrared absorption spectroscopy, 45 Sc nuclear magnetic resonance, and cyclic voltammetry. Comparative studies of the motion of the carbide cluster in Sc 2 C 2 @D 3h (14246)-C 74 and Sc 2 C 2 @C 2n (n = 40-44) revealed that a combination of factors, involving both the shape and size of the cage, is crucial in dictating the cluster motion. Moreover, structural studies of D 3h (14246)-C 74 revealed that it can be easily converted to C s (10528)-C 72 and T d (19151)-C 76 cages via C 2 desertion/insertion and Stone-Wales transformation. This suggests that D 3h (14246)-C 74 might play an important role in the growth pathway of clusterfullerenes.

Tourism at Risk: Failures and Dichotomies of Risk Perception Theory in Tourism (Opinion Piece

Directory of Open Access Journals (Sweden)

Maximiliano E. KORSTANJE

2017-12-01

Full Text Available The turn of the century has brought a lot of radical shifts and risks for tourism industry, which ranged from terrorism to lethal virus outbreaks. Henceforth risk perception theory, which was formulated in psychology, was re-appropriated by policy makers and tourism-related scholars. However, from its inception this conceptual corpus was based on the economic-centred paradigm. This piece discusses critically the main limitations of risk perception theory and the rise of a new discipline, post disaster marketing, in view of the caveats and speculative assumption of “the precautionary principle”.

Modified snap-on attachment with ′O-ring′ for two piece hollow bulb obturator

Directory of Open Access Journals (Sweden)

C Gunasekar

2013-01-01

Full Text Available Restoration of near normal functions in patients who have been treated with hemimaxillectomy is generally difficult, in view of the restriction in mouth opening following healing of large surgical wound. Further, the extent and nature of the surgical defect differ from patient to patient. Thus, design of an obturator needs to be patient oriented. In this report, we describe a novel snap-on attachment with O-ring in a conventional two piece hollow bulb obturator for a 70-year-old male treated for carcinoma of the left maxilla and sinus.

Improved Nyquist Pulses Produced By A Filter with Senary Piece-wise Polynomial Frequency Characteristic

Directory of Open Access Journals (Sweden)

BALAN, A. L.

2014-05-01

Full Text Available A novel family of inter-symbol interference (ISI free pulses generated by improved Nyquist filters with a frequency characteristic composed of six parabolic pieces is proposed. We studied the performance of the new pulses in terms of the ISI error probability when the impulse response is sampled with a timing offset. To illustrate the achieved improvement, the new pulses are compared with other performing pulses that were reported in the literature. Simulation results show that comparable or enhanced ISI performance can be obtained at reasonable complexity.

The nesprin-cytoskeleton interface probed directly on single nuclei is a mechanically rich system.

Science.gov (United States)

Balikov, Daniel A; Brady, Sonia K; Ko, Ung Hyun; Shin, Jennifer H; de Pereda, Jose M; Sonnenberg, Arnoud; Sung, Hak-Joon; Lang, Matthew J

2017-09-03

The cytoskeleton provides structure and plays an important role in cellular function such as migration, resisting compression forces, and transport. The cytoskeleton also reacts to physical cues such as fluid shear stress or extracellular matrix remodeling by reorganizing filament associations, most commonly focal adhesions and cell-cell cadherin junctions. These mechanical stimuli can result in genome-level changes, and the physical connection of the cytoskeleton to the nucleus provides an optimal conduit for signal transduction by interfacing with nuclear envelope proteins, called nesprins, within the LINC (linker of the nucleus to the cytoskeleton) complex. Using single-molecule on single nuclei assays, we report that the interactions between the nucleus and the cytoskeleton, thought to be nesprin-cytoskeleton interactions, are highly sensitive to force magnitude and direction depending on whether cells are historically interfaced with the matrix or with cell aggregates. Application of ∼10-30 pN forces to these nesprin linkages yielded structural transitions, with a base transition size of 5-6 nm, which are speculated to be associated with partial unfoldings of the spectrin domains of the nesprins and/or structural changes of histones within the nucleus.

Cueing musical emotions: An empirical analysis of 24-piece sets by Bach and Chopin documents parallels with emotional speech.

Science.gov (United States)

Poon, Matthew; Schutz, Michael

2015-01-01

Acoustic cues such as pitch height and timing are effective at communicating emotion in both music and speech. Numerous experiments altering musical passages have shown that higher and faster melodies generally sound "happier" than lower and slower melodies, findings consistent with corpus analyses of emotional speech. However, equivalent corpus analyses of complex time-varying cues in music are less common, due in part to the challenges of assembling an appropriate corpus. Here, we describe a novel, score-based exploration of the use of pitch height and timing in a set of "balanced" major and minor key compositions. Our analysis included all 24 Preludes and 24 Fugues from Bach's Well-Tempered Clavier (book 1), as well as all 24 of Chopin's Preludes for piano. These three sets are balanced with respect to both modality (major/minor) and key chroma ("A," "B," "C," etc.). Consistent with predictions derived from speech, we found major-key (nominally "happy") pieces to be two semitones higher in pitch height and 29% faster than minor-key (nominally "sad") pieces. This demonstrates that our balanced corpus of major and minor key pieces uses low-level acoustic cues for emotion in a manner consistent with speech. A series of post hoc analyses illustrate interesting trade-offs, with sets featuring greater emphasis on timing distinctions between modalities exhibiting the least pitch distinction, and vice-versa. We discuss these findings in the broader context of speech-music research, as well as recent scholarship exploring the historical evolution of cue use in Western music.

Security analysis with improved design of post-confirmation mechanism for quantum sealed-bid auction with single photons

Science.gov (United States)

Zhang, Ke-Jia; Kwek, Leong-Chuan; Ma, Chun-Guang; Zhang, Long; Sun, Hong-Wei

2018-02-01

Quantum sealed-bid auction (QSA) has been widely studied in quantum cryptography. For a successful auction, post-confirmation is regarded as an important mechanism to make every bidder verify the identity of the winner after the auctioneer has announced the result. However, since the auctioneer may be dishonest and collude with malicious bidders in practice, some potential loopholes could exist. In this paper, we point out two types of collusion attacks for a particular post-confirmation technique with EPR pairs. And it is not difficult to see that there exists no unconditionally secure post-confirmation mechanism in the existing QSA model, if the dishonest participants have the ability to control multiparticle entanglement. In the view of this, we note that some secure implementation could exist if the participants are supposed to be semi-quantum, i.e., they can only control single photons. Finally, two potential methods to design post-confirmation mechanism are presented in this restricted scenario.

Structural, mechanical and light yield characterisation of heat treated LYSO:Ce single crystals for medical imaging applications

CERN Document Server

Mengucci, P; Auffray, E; Barucca, G; Cecchi, C; Chipaux, R; Cousson, A; Davì, F; Di Vara, N; Rinaldi, D; Santecchia, E

2015-01-01

Five single crystals of cerium-doped lutetium yttrium oxyorthosilicate (LYSO:Ce) grown by the Czochralski method were submitted to structural characterisation by X-ray (XRD) and neutron (ND) diffraction, scanning (SEM) and transmission (TEM) electron microscopy and energy dispersive microanalysis (EDS). The Ultimate Tensile Strength (UTS), the Young Modulus (YM) and the Light Yield (LY) of the samples were also measured in order to correlate the mechanical and the optical behaviour of the crystals with the characteristics of their microstructure. Two of the samples analysed were also heat treated at 300 °C for 10 h to evidence possible variations induced by the temperature in the optical and mechanical response of the crystals. Results showed that the mean compositional variations evidenced by the structural analyses do not affect the mechanical and optical behaviour of the samples. On the contrary, the thermal treatment could induce the formation of coherent spherical particles (size 10 to 15 nm), not unifo...

Deformation Mechanism and Recrystallization Relationships in Galfenol Single Crystals: On the Origin of Goss and Cube Orientations

Science.gov (United States)

Na, Suok-Min; Smith, Malcolm; Flatau, Alison B.

2018-06-01

In this work, deformation mechanism related to recrystallization behavior in single-crystal disks of Galfenol (Fe-Ga alloy) was investigated to gain insights into the influence of crystal orientations on structural changes and selective grain growth that take place during secondary recrystallization. We started with the three kinds of single-crystal samples with (011)[100], (001)[100], and (001)[110] orientations, which were rolled and annealed to promote the formation of different grain structures and texture evolutions. The initial Goss-oriented (011)[100] crystal mostly rotated into {111} orientations with twofold symmetry and shear band structures by twinning resulted in the exposure of rolled surface along {001} orientation during rolling. In contrast, the Cube-oriented (001)[100] single crystal had no change in texture during rolling with the thickness reduction up to 50 pct. The {123} slip systems were preferentially activated in these single crystals during deformation as well as {112} slip systems that are known to play a role in primary slip of body-centered cubic (BCC) materials such as α-iron and Fe-Si alloys. After annealing, the deformed Cube-oriented single crystal had a small fraction ( orientation, associated with {123} slip systems as well. This was expected to provide potential sites of nucleation for secondary recrystallization; however, no Goss- and Cube-oriented components actually developed in this sample during secondary recrystallization. Those results illustrated how the recrystallization behavior can be influenced by deformed structure and the slip systems.

CVD-grown horizontally aligned single-walled carbon nanotubes: synthesis routes and growth mechanisms.

Science.gov (United States)

Ibrahim, Imad; Bachmatiuk, Alicja; Warner, Jamie H; Büchner, Bernd; Cuniberti, Gianaurelio; Rümmeli, Mark H

2012-07-09

Single-walled carbon nanotubes (SWCNTs) have attractive electrical and physical properties, which make them very promising for use in various applications. For some applications however, in particular those involving electronics, SWCNTs need to be synthesized with a high degree of control with respect to yield, length, alignment, diameter, and chirality. With this in mind, a great deal of effort is being directed to the precision control of vertically and horizontally aligned nanotubes. In this review the focus is on the latter, horizontally aligned tubes grown by chemical vapor deposition (CVD). The reader is provided with an in-depth review of the established vapor deposition orientation techniques. Detailed discussions on the characterization routes, growth parameters, and growth mechanisms are also provided. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wire-based laser metal deposition for additive manufacturing of TiAl6V4: basic investigations of microstructure and mechanical properties from build up parts

Science.gov (United States)

Klocke, Fritz; Arntz, Kristian; Klingbeil, Nils; Schulz, Martin

2017-02-01

The wire-based laser metal deposition (LMD-W) is a new technology which enables to produce complex parts made of titanium for the aerospace and automotive industry. For establishing the LMD-W as a new production process it has to be proven that the properties are comparable or superior to conventional produced parts. The mechanical properties were investigated by analysis of microstructure and tensile test. Therefore, specimens were generated using a 4.5 kW diode laser cladding system integrated in a 5-Axis-machining center. The structural mechanical properties are mainly influence by crystal structure and thereby the thermal history of the work piece. Especially the high affinity to oxide, distortion and dual phase microstructure make titanium grade 5 (TiAl6V4) one of the most challenging material for additive manufacturing. By using a proper local multi-nozzle shielding gas concept the negative influence of oxide in the process could be eliminated. The distortion being marginal at a single bead, accumulated to a macroscopic effect on the work piece. The third critical point for additive processing of titanium, the bimodal microstructure, could not be cleared by the laser process alone. All metallurgical probes showed α-martensitic-structure. Therefore, a thermal treatment became a necessary production step in the additive production chain. After the thermal treatment the microstructure as well as the distortion was analyzed and compared with the status before. Although not all technical issues could be solved, the investigation show that LMD-W of titanium grade 5 is a promising alternative to other additive techniques as electronic beam melting or plasma deposition welding.

Thermal, mechanical, optical and dielectric properties of piperazinium hydrogen phosphite monohydrate NLO single crystal

Science.gov (United States)

Rajkumar, R.; Praveen Kumar, P.

2018-05-01

Optical transparent crystal of piperazinium hydrogen phosphite monohydrate (PHPM) was grown by slow evaporation method. The grown crystal was characterized by single crystal X-ray diffraction analysis and the crystal belongs to monoclinic system. The functional groups present in PHPM crystal were confirmed by FTIR analysis. UV-Visible spectrum shows that the PHPM crystal is transparent in the visible region. The mechanical behavior of PHPM crystal was characterized by Vickers hardness test. Thermal stability of PHPM crystal was analyzed by thermogravimetric analysis. Dielectric studies were also carried out for the grown crystal. The third-order nonlinear parameters such as nonlinear refractive index and nonlinear absorption coefficient have been calculated using Z scan technique.

Single-suture scleral fixation of subluxated foldable intraocular lenses.

Science.gov (United States)

Yarangumeli, Alper; Alp, Mehmet Numan; Kural, Gulcan

2012-01-01

To evaluate the results of single-suture scleral fixation of subluxated foldable intraocular lenses (IOL) in eyes with sufficient residual capsular support. The results of IOL repositioning by single-suture scleral fixation in 6 eyes of 6 patients with IOL subluxation were included. All subluxated IOLs were single-piece hydrophilic acrylic. Subluxation resulted from posterior capsule tears in 3 eyes, zonular dialyses in 2 eyes, and zonular dialysis with a capsulorhexis tear in 1 eye. A similar technique was used in all eyes in which one haptic was externalized through a superior clear corneal incision and tied with a Pair-PAK 10-0 polypropylene suture, and was finally retracted and fixated behind the iris close to the ciliary sulcus at the 12:00 meridian. All patients were followed up for at least 6 months. Best-corrected visual acuities ranged between finger counting and 20/70 (mean logMAR 1.02±0.64) preoperatively, and between 20/100 and 20/20 (mean logMAR 0.22±0.26) at the final postoperative visit. All IOLs remained centered and no significant postoperative complications were encountered except for an IOL tilt which resulted in a considerable oblique astigmatism in one eye. Subluxated foldable IOLs may safely be repositioned and secured with a single scleral fixation suture in selected cases with adequate amount of capsular remnants.

Optimal mechanisms for single machine scheduling

NARCIS (Netherlands)

Heydenreich, B.; Mishra, D.; Müller, R.; Uetz, Marc Jochen; Papadimitriou, C.; Zhang, S.

2008-01-01

We study the design of optimal mechanisms in a setting here job-agents compete for being processed by a service provider that can handle one job at a time. Each job has a processing time and incurs a waiting cost. Jobs need to be compensated for waiting. We consider two models, one where only the

Bridging Type 2 Diabetes and Alzheimer's Disease: Assembling the Puzzle Pieces in the Quest for the Molecules With Therapeutic and Preventive Potential.

Science.gov (United States)

de Matos, Ana Marta; de Macedo, Maria Paula; Rauter, Amélia Pilar

2018-01-01

Type 2 diabetes (T2D) and Alzheimer's disease (AD) are two age-related amyloid diseases that affect millions of people worldwide. Broadly supported by epidemiological data, the higher incidence of AD among type 2 diabetic patients led to the recognition of T2D as a tangible risk factor for the development of AD. Indeed, there is now growing evidence on brain structural and functional abnormalities arising from brain insulin resistance and deficiency, ultimately highlighting the need for new approaches capable of preventing the development of AD in type 2 diabetic patients. This review provides an update on overlapping pathophysiological mechanisms and pathways in T2D and AD, such as amyloidogenic events, oxidative stress, endothelial dysfunction, aberrant enzymatic activity, and even shared genetic background. These events will be presented as puzzle pieces put together, thus establishing potential therapeutic targets for drug discovery and development against T2D and diabetes-induced cognitive decline-a heavyweight contributor to the increasing incidence of dementia in developed countries. Hoping to pave the way in this direction, we will present some of the most promising and well-studied drug leads with potential against both pathologies, including their respective bioactivity reports, mechanisms of action, and structure-activity relationships. © 2017 Wiley Periodicals, Inc.

Oxygenation with T-piece versus self-inflating bag for ventilation of extremely preterm infants at birth: a randomized controlled trial.

LENUS (Irish Health Repository)

Dawson, Jennifer A

2011-06-01

To investigate whether infants < 29 weeks gestation who receive positive pressure ventilation (PPV) immediately after birth with a T-piece have higher oxygen saturation (SpO₂) measurements at 5 minutes than infants ventilated with a self inflating bag (SIB).

Role of solvent environments in single molecule conductance used insulator-modified mechanically controlled break junctions

Science.gov (United States)

Muthusubramanian, Nandini; Maity, Chandan; Galan Garcia, Elena; Eelkema, Rienk; Grozema, Ferdinand; van der Zant, Herre; Kavli Institute of Nanoscience Collaboration; Department of Chemical Engineering Collaboration

We present a method for studying the effects of polar solvents on charge transport through organic/biological single molecules by developing solvent-compatible mechanically controlled break junctions of gold coated with a thin layer of aluminium oxide using plasma enhanced atomic layer deposition (ALD). The optimal oxide thickness was experimentally determined to be 15 nm deposited at ALD operating temperature of 300°C which yielded atomically sharp electrodes and reproducible single-barrier tunnelling behaviour across a wide conductance range between 1 G0 and 10-7 G0. The insulator protected MCBJ devices were found to be effective in various solvents such as deionized water, phosphate buffered saline, methanol, acetonitrile and dichlorobenzene. The yield of molecular junctions using such insulated electrodes was tested by developing a chemical protocol for synthesizing an amphipathic form of oligo-phenylene ethynylene (OPE3-PEO) with thioacetate anchoring groups. This work has further applications in studying effects of solvation, dipole orientation and other thermodynamic interactions on charge transport. Eu Marie Curie Initial Training Network (ITN). MOLECULAR-SCALE ELECTRONICS: ``MOLESCO'' Project Number 606728.

Viewpoint: Telecommunications and Internet Broadband Policy: Sorting Out the Pieces for Telerehabilitation

Directory of Open Access Journals (Sweden)

Kate D. Seelman

2010-09-01

Full Text Available Technological change is accelerating and with it regulatory upheaval.  Most of us agree that providing universal telecommunication services to all our citizens is a worthy ideal.  Nonetheless, many of us do not agree that regulation should be the means to make broadband Internet services widely available. This Viewpoint begins sorting out pieces of the emerging United States, regulatory and policy puzzle for broadband Internet with an eye to the interests of telerehabilitation providers and consumers. Just how might changes in legal authority, regulation and agency jurisdictions impact us?Key words: telecommunications regulation, telerehabilitation, Federal Communications Commission (FCC, Telecommunications Act of 1996, National Broadband Plan; Comcast vs. FCC; electronic health records (EHR; personal health records (PHR; health information technology (HIT, 

Application of the 2-piece orthodontic C-implant for provisional restoration with laser welded customized coping: a case report.

Science.gov (United States)

Paek, Janghyun; Ahn, Hyo-Won; Jeong, Do-Min; Shim, Jeong-Seok; Kim, Seong-Hun; Chung, Kyu-Rhim

2015-03-25

This article presents the application of laser welding technique to fabricate an orthodontic mini-implant provisional restoration in missing area after limited orthodontic treatment. A 15-year-old boy case is presented. Two-piece orthodontic C-implant was placed after regaining space for missing right mandibular central incisor. Due to angular deviation of implant, customized abutment was required. Ready-made head part was milled and lingual part of customized abutment was made with non-precious metal. Two parts then were laser welded (Master 1000, Elettrolaser Italy, Verona, Italy) and indirect lab composite (3 M ESPE Sinfony, St. Paul, MN, USA) was built up. The patient had successful result, confirmed by clinical and radiographic examinations. Before the patient is ready to get a permanent restoration later on, this provisional restoration will be used. This case shows that a two-piece orthodontic C-implant system can be used to maintain small edentulous space after orthodontic treatment.

Low inductance diode design on the Proto II accelerator for imploding plasma loads

International Nuclear Information System (INIS)

Hsing, W.W.; Coats, R.; McDaniel, D.H.; Spielman, R.B.

1985-01-01

A new water transmission line convolute, single piece insulator, and double disk feed has been designed and tested on the .125 ohm, 10 TW Proto II accelerator. The water transmission lines have a 5 cm gap to eliminate any water arcing. A two-dimensional magnetic field code was used to calculate the convolute inductance. We used an acrylic insulator as well as a single piece, laminated polycarbonate insulator. They have been succuessfully tested at over 90% of the Shipman criteria for classical insulator breakdown, although the laminations in the polycarbonate insulator failed after a few shots. The anode and cathode each have two pieces and are held together mechanically. The vacuum MITL tapers to a 3 mm minimum gap. The total inductance is 8.4 nH for gas puff loads and 7.8 nH for imploding foil loads. Out of a forward-going energy of 290 kJ, 175 kJ has been delivered past the insulator, and 100 kJ has been successfully delivered to the load

Analytical modelling of Halbach linear generator incorporating pole shifting and piece-wise spring for ocean wave energy harvesting

Science.gov (United States)

Tan, Yimin; Lin, Kejian; Zu, Jean W.

2018-05-01

Halbach permanent magnet (PM) array has attracted tremendous research attention in the development of electromagnetic generators for its unique properties. This paper has proposed a generalized analytical model for linear generators. The slotted stator pole-shifting and implementation of Halbach array have been combined for the first time. Initially, the magnetization components of the Halbach array have been determined using Fourier decomposition. Then, based on the magnetic scalar potential method, the magnetic field distribution has been derived employing specially treated boundary conditions. FEM analysis has been conducted to verify the analytical model. A slotted linear PM generator with Halbach PM has been constructed to validate the model and further improved using piece-wise springs to trigger full range reciprocating motion. A dynamic model has been developed to characterize the dynamic behavior of the slider. This analytical method provides an effective tool in development and optimization of Halbach PM generator. The experimental results indicate that piece-wise springs can be employed to improve generator performance under low excitation frequency.

Analytical modelling of Halbach linear generator incorporating pole shifting and piece-wise spring for ocean wave energy harvesting

Directory of Open Access Journals (Sweden)

Yimin Tan

2018-05-01

Full Text Available Halbach permanent magnet (PM array has attracted tremendous research attention in the development of electromagnetic generators for its unique properties. This paper has proposed a generalized analytical model for linear generators. The slotted stator pole-shifting and implementation of Halbach array have been combined for the first time. Initially, the magnetization components of the Halbach array have been determined using Fourier decomposition. Then, based on the magnetic scalar potential method, the magnetic field distribution has been derived employing specially treated boundary conditions. FEM analysis has been conducted to verify the analytical model. A slotted linear PM generator with Halbach PM has been constructed to validate the model and further improved using piece-wise springs to trigger full range reciprocating motion. A dynamic model has been developed to characterize the dynamic behavior of the slider. This analytical method provides an effective tool in development and optimization of Halbach PM generator. The experimental results indicate that piece-wise springs can be employed to improve generator performance under low excitation frequency.

Effect of Ethanol Stress on Fermentation Performance of Saccharomyces cerevisiae Cells Immobilized on Nypa fruticans Leaf Sheath Pieces

Directory of Open Access Journals (Sweden)

Hoang Phong Nguyen

2015-01-01

Full Text Available The yeast cells of Saccharomyces cerevisiae immobilized on Nypa fruticans leaf sheath pieces were tested for ethanol tolerance (0, 23.7, 47.4, 71.0 and 94.7 g/L. Increase in the initial ethanol concentration from 23.7 to 94.7 g/L decreased the average growth rate and concentration of ethanol produced by the immobilized yeast by 5.2 and 4.1 times, respectively. However, in the medium with initial ethanol concentration of 94.7 g/L, the average growth rate, glucose uptake rate and ethanol formation rate of the immobilized yeast were 3.7, 2.5 and 3.5 times, respectively, higher than those of the free yeast. The ethanol stress inhibited ethanol formation by Saccharomyces cerevisiae cells and the yeast responded to the stress by changing the fatty acid composition of cellular membrane. The adsorption of yeast cells on Nypa fruticans leaf sheath pieces of the growth medium increased the saturated fatty acid (C16:0 and C18:0 mass fraction in the cellular membrane and that improved alcoholic fermentation performance of the immobilized yeast.

Draft forces prediction model for standard single tines by using principles of soil mechanics and soil profile evaluation

Directory of Open Access Journals (Sweden)

Amer Khalid Ahmed Al-Neama

2017-06-01

Full Text Available This paper explains a model to predict the draft force acting on varying standard single tines by using principles of soil mechanics and soil profile evaluation. Draft force (Fd measurements were made with four standard single tines comprising Heavy Duty, Double Heart, Double Heart with Wings and Duck Foot. Tine widths were 6.5, 13.5, 45 and 40 cm, respectively. The test was conducted in a soil bin with sandy loam soil. The effects of forward speeds and working depths on draft forces were investigated under controlled lab conditions. Results were evaluated based on a prediction model. A good correlation between measured and predicted Fd values for all tines with an average absolute variation less than 15 % was found.

Retinoic acid signaling: a new piece in the spoken language puzzle

Directory of Open Access Journals (Sweden)

Jon-Ruben eVan Rhijn

2015-11-01

Full Text Available Speech requires precise motor control and rapid sequencing of highly complex vocal musculature. Despite its complexity, most people produce spoken language effortlessly. This is due to activity in distributed neuronal circuitry including cortico-striato-thalamic loops that control speech-motor output. Understanding the neuro-genetic mechanisms that encode these pathways will shed light on how humans can effortlessly and innately use spoken language and could elucidate what goes wrong in speech-language disorders.FOXP2 was the first single gene identified to cause speech and language disorder. Individuals with FOXP2 mutations display a severe speech deficit that also includes receptive and expressive language impairments. The underlying neuro-molecular mechanisms controlled by FOXP2, which will give insight into our capacity for speech-motor control, are only beginning to be unraveled. Recently FOXP2 was found to regulate genes involved in retinoic acid signaling and to modify the cellular response to retinoic acid, a key regulator of brain development. Herein we explore the evidence that FOXP2 and retinoic acid signaling function in the same pathways. We present evidence at molecular, cellular and behavioral levels that suggest an interplay between FOXP2 and retinoic acid that may be important for fine motor control and speech-motor output. We propose that retinoic acid signaling is an exciting new angle from which to investigate how neurogenetic mechanisms can contribute to the (spoken language ready brain.

Study of the mechanical properties of single- layer and multi-layer metallic coatings with protective-decorative applications

Directory of Open Access Journals (Sweden)

Cherneva Sabina

2018-01-01

Full Text Available Single thin coating of matt nickel (Nimat, a mirror bright copper (Cubright, a mirror bright nickel (Nibright and their combinations were electrochemically deposited on brass substrate with thickness 500 μm. The basic aim was electrodeposition of two-layer Cubright/Nimat and Nibright/Cubright systems, and three-layer Nibright Cubrigh/Nimat system, which are among the most widely applied protective and decorative systems in light and medium operating conditions of corrosion. The thicknesses of the obtained films varied from 1 μm to 3.25 μm. They were investigated via nanoindentation experiments, in order to characterize their basic physical and mechanical characteristics, related with their good adhesion and corrosion protective ability, as well as ensuring the integrity of the system “protective coating/substrate” to possible mechanical, dynamic and/or thermal stresses. As a result, load-displacement curves were obtained and indentation hardness and indentation modulus were calculated using the Oliver & Pharr approximation method. The dependence of the indentation modulus and the indentation hardness on the depth of the indentation, surface morphology and structure of the obtained coatings, their texture and surface roughness were investigated too. The obtained results showed that the three-layer Nibright/Cubright /Niimat/CuZn37 system has highest indentation modulus and indentation hardness, following by two-layer Nibright/Cubright system and single layer coatings.

A new mask to prevent environmental contamination during radio aerosol mouth-piece inhalation procedures

International Nuclear Information System (INIS)

Braga, Francisco Jose Hossri Nogueira.

1994-01-01

Environmental contamination is frequent during labelled aerosol mouth-piece inhalation procedures. Previous personnel data showed that in 18/18 situations air background activity has increased after inhalation and this may create serious routine and economical problems. We have tested a new adherent mask made of 3 M's TEGADERM in sixty 99 m Tc-DTPA inhalation studies and the results indicates that the use of such a mask may eliminate the problem of environmental contamination. The device is useful but not entirely efficient in cases when good skin adherence cannot be obtained. 48 refs, 10 figs, 2 tabs

Mechanical properties of ceramic structures based on Triply Periodic Minimal Surface (TPMS) processed by 3D printing

Science.gov (United States)

Restrepo, S.; Ocampo, S.; Ramírez, J. A.; Paucar, C.; García, C.

2017-12-01

Repairing tissues and organs has been the main goal of surgical procedures. Since the 1990s, the main goal of tissue engineering has been reparation, using porous scaffolds that serve as a three-dimensional template for the initial fixation of cells and subsequent tissue formation both in vitro and in vivo. A scaffold must have specific characteristics of porosity, interconnectivity, surface area, pore volume, surface tortuosity, permeability and mechanical properties, which makes its design, manufacturing and characterization a complex process. Inspired by nature, triply periodic minimal surfaces (TPMS) have emerged as an alternative for the manufacture of porous pieces with design requirements, such as scaffolds for tissue repair. In the present work, we used the technique of 3D printing to obtain ceramic structures with Gyroid, Schwarz Primitive and Schwarz Diamond Surfaces shapes, three TPMS that fulfil the geometric requirements of a bone tissue scaffold. The main objective of this work is to compare the mechanical properties of ceramic pieces of three different forms of TPMS printed in 3D using a commercial ceramic paste. In this way it will be possible to clarify which is the TPMS with appropriate characteristics to construct scaffolds of ceramic materials for bone repair. A dependence of the mechanical properties with the geometry was found being the Primitive Surface which shows the highest mechanical properties.

Insulator-protected mechanically controlled break junctions for measuring single-molecule conductance in aqueous environments

Science.gov (United States)

Muthusubramanian, N.; Galan, E.; Maity, C.; Eelkema, R.; Grozema, F. C.; van der Zant, H. S. J.

2016-07-01

We present a method to fabricate insulated gold mechanically controlled break junctions (MCBJ) by coating the metal with a thin layer of aluminum oxide using plasma enhanced atomic layer deposition. The Al2O3 thickness deposited on the MCBJ devices was varied from 2 to 15 nm to test the suppression of leakage currents in deionized water and phosphate buffered saline. Junctions coated with a 15 nm thick oxide layer yielded atomically sharp electrodes and negligible conductance counts in the range of 1 to 10-4 G0 (1 G0 = 77 μS), where single-molecule conductances are commonly observed. The insulated devices were used to measure the conductance of an amphiphilic oligophenylene ethynylene derivative in deionized water.

Experimental results of single screw mechanical tests: a follow-up to SAND2005-6036.

Energy Technology Data Exchange (ETDEWEB)

Lee, Sandwook; Lee, Kenneth L.; Korellis, John S.; McFadden, Sam X.

2006-08-01

The work reported here was conducted to address issues raised regarding mechanical testing of attachment screws described in SAND2005-6036, as well as to increase the understanding of screw behavior through additional testing. Efforts were made to evaluate fixture modifications and address issues of interest, including: fabrication of 45{sup o} test fixtures, measurement of the frictional load from the angled fixture guide, employment of electromechanical displacement transducers, development of a single-shear test, and study the affect of thread start orientation on single-shear behavior. A286 and 302HQ, No.10-32 socket-head cap screws were tested having orientations with respect to the primary loading axis of 0{sup 0}, 45{sup o}, 60{sup o}, 75{sup o} and 90{sup o} at stroke speeds 0,001 and 10 in/sec. The frictional load resulting from the angled screw fixture guide was insignificant. Load-displacement curves of A286 screws did not show a minimum value in displacement to failure (DTF) for 60{sup o} shear tests. Tests of 302HQ screws did not produce a consistent trend in DTF with load angle. The effect of displacement rate on DTF became larger as shear angle increased for both A286 and 302HQ screws.

Investigation of the Microstructure and Mechanical Properties of Copper-Graphite Composites Reinforced with Single-Crystal α-Al₂O₃ Fibres by Hot Isostatic Pressing.

Science.gov (United States)

Zhang, Guihang; Jiang, Xiaosong; Qiao, ChangJun; Shao, Zhenyi; Zhu, Degui; Zhu, Minhao; Valcarcel, Victor

2018-06-11

Single-crystal α-Al₂O₃ fibres can be utilized as a novel reinforcement in high-temperature composites owing to their high elastic modulus, chemical and thermal stability. Unlike non-oxide fibres and polycrystalline alumina fibres, high-temperature oxidation and polycrystalline particles boundary growth will not occur for single-crystal α-Al₂O₃ fibres. In this work, single-crystal α-Al₂O₃ whiskers and Al₂O₃ particles synergistic reinforced copper-graphite composites were fabricated by mechanical alloying and hot isostatic pressing techniques. The phase compositions, microstructures, and fracture morphologies of the composites were investigated using X-ray diffraction, a scanning electron microscope equipped with an X-ray energy-dispersive spectrometer (EDS), an electron probe microscopic analysis equipped with wavelength-dispersive spectrometer, and a transmission electron microscope equipped with EDS. The mechanical properties have been measured by a micro-hardness tester and electronic universal testing machine. The results show that the reinforcements were unevenly distributed in the matrix with the increase of their content and there were some micro-cracks located at the interface between the reinforcement and the matrix. With the increase of the Al₂O₃ whisker content, the compressive strength of the composites first increased and then decreased, while the hardness decreased. The fracture and strengthening mechanisms of the composite materials were explored on the basis of the structure and composition of the composites through the formation and function of the interface. The main strengthening mechanism in the composites was fine grain strengthening and solid solution strengthening. The fracture type of the composites was brittle fracture.

A novel computer-aided method to fabricate a custom one-piece glass fiber dowel-and-core based on digitized impression and crown preparation data.

Science.gov (United States)

Chen, Zhiyu; Li, Ya; Deng, Xuliang; Wang, Xinzhi

2014-06-01

Fiber-reinforced composite dowels have been widely used for their superior biomechanical properties; however, their preformed shape cannot fit irregularly shaped root canals. This study aimed to describe a novel computer-aided method to create a custom-made one-piece dowel-and-core based on the digitization of impressions and clinical standard crown preparations. A standard maxillary die stone model containing three prepared teeth each (maxillary lateral incisor, canine, premolar) requiring dowel restorations was made. It was then mounted on an average value articulator with the mandibular stone model to simulate natural occlusion. Impressions for each tooth were obtained using vinylpolysiloxane with a sectional dual-arch tray and digitized with an optical scanner. The dowel-and-core virtual model was created by slicing 3D dowel data from impression digitization with core data selected from a standard crown preparation database of 107 records collected from clinics and digitized. The position of the chosen digital core was manually regulated to coordinate with the adjacent teeth to fulfill the crown restorative requirements. Based on virtual models, one-piece custom dowel-and-cores for three experimental teeth were milled from a glass fiber block with computer-aided manufacturing techniques. Furthermore, two patients were treated to evaluate the practicality of this new method. The one-piece glass fiber dowel-and-core made for experimental teeth fulfilled the clinical requirements for dowel restorations. Moreover, two patients were treated to validate the technique. This novel computer-aided method to create a custom one-piece glass fiber dowel-and-core proved to be practical and efficient. © 2013 by the American College of Prosthodontists.

Behaviour and lifetime of multi-perforated parts: application to turbine blades; Comportement et duree de vie des pieces multiperforees: application aux aubes de turbine

Energy Technology Data Exchange (ETDEWEB)

Cardona, J.M.

2000-12-15

High-pressure turbine blades are submitted to very high thermal and mechanical constraints but also variable with time, thus leading to combined fatigue and creep phenomena. Micro-channels are an efficient mean to reduce the global temperature of parts but they generate temperature gradients and stress concentrations which can be at the origin of cracks. Thus, geometrical singularities are important factors to take into consideration in the analysis of the behaviour and lifetime of HP turbine blades. A 3D calculation of a multi-perforated blade has been performed in isotropic and anisotropic elasticity and visco-plasticity conditions and in isothermal and aniso-thermal conditions. A dimensioning method for turbine blades, based on homogenization methods, has been proposed. It allows to replace the heterogenous area (the holes of the leading edge) by an equivalent homogenous medium having effective properties. This medium has been determined in elasticity using classical homogenization methods, and then in isotropic viscosity and in the monocrystal case using a pragmatic method. The preconized homogenization methods comprise a relocation step allowing to use the informations of the simplified calculation in order to apply suitable boundary conditions to a representative cell with a single cooling hole. Because the reference calculation gives the constraints-deformations status around the holes, the result given by the relocation method can be unambiguously evaluated. The limitations of such an approach in the case of strong stress gradients has been evidenced. In these conditions of operation, the classical homogenization methods are not suitable and the equivalent homogenous medium can be considered as a generalized continuous medium. A thermo-elasticity formulation of the second gradient is proposed. An experimental study has been carried out in parallel at the ONERA in order to analyze the influence of perforation on the behaviour and lifetime. Thermo-mechanical

A welding device for a socket in a hard-to-get-to circular pipe connection piece

International Nuclear Information System (INIS)

Deschamps, J.P.

1995-01-01

The welding device allows for the assembly of a socket inside the collection piece of an auxiliary pipe at the bottom of a dissolver tube; the device comprises a support around which is mounted a rotating welding head with a gear motor. Clamping of the socket around the head is achieved by the means of pneumatically driven clamping sections. A pulley and gutter tension device is aimed at securing the electric and metal supply cables. 9 refs., 3 figs

Stress Analysis of Single Spacer Grid Support considering Fuel Rod

Energy Technology Data Exchange (ETDEWEB)

Yoo, Y. G.; Jung, D. H.; Kim, J. H. [Chungnam National University, Daejeon (Korea, Republic of); Park, J. K.; Jeon, K. L. [Korea Nuclear Fuel, Daejeon (Korea, Republic of)

2010-10-15

Pressurized water reactor (PWR) nuclear fuel assembly is mainly composed of a top-end piece, a bottom-end piece, lots of fuel rods, and several spacer grids. Among them, the main function of spacer grid is protecting fuel rods from Fluid Induced Vibration (FIV). The cross section of spacer grid assembled by laser welding in upper and lower point. When the fuel rod inserted in spacer gird, spring and dimple and around of welded area got a stresses. The main hypothesis of this analysis is the boundary area of HAZ and base metal can get a lot of damage than other area by FIV. So, design factors of spacer grid mainly considered to preventing the fatigue failure in HAZ and spring and dimple of spacer grid. From previous researching, the environment in reactor verified. Pressure and temperature of light water observed 15MPa and 320 .deg. C, and vibration of the fuel rod observed within 0 {approx} 50Hz. In this study, mechanical properties of zirconium alloy that extracted from the test and the spacer grid model which used in the PWR were applied in stress analyzing. General-purpose finite element analysis program was used ANSYS Workbench 12.0.1 version. 3-D CAD program CATIA was used to create spacer grid model

Equipment for manufacture of single crystals by zone overlaying

International Nuclear Information System (INIS)

Richter, O.

1981-01-01

The patented heater element for the manufacture of monocrystals by zone melting of layers consists of a heated pipe with insert slipped onto the heated pipe or consisting, in turn, of pieces fixed parallel to the heated pipe or a piece placed between two pipes. The insert is designed for stabilizing the melt surface. (Ha)

Modification of mechanical properties of single crystal aluminum oxide by ion beam induced structural changes

International Nuclear Information System (INIS)

Ensinger, W.; Nowak, R.; Horino, Y.; Baba, K.

1993-01-01

The mechanical behaviour of ceramics is essentially determined by their surface qualities. As a surface modification technique, ion implantation provides the possibility to modify the mechanical properties of ceramics. Highly energetic ions are implanted into the near-surface region of a material and modify its composition and structure. Ions of aluminum, oxygen, nickel and tantalum were implanted into single-crystal α-aluminum oxide. Three-point bending tests showed that an increase in flexural strength of up to 30% could be obtained after implantation of aluminum and oxygen. Nickel and tantalum ion implantation increased the fracture toughness. Indentation tests with Knoop and Vickers diamonds and comparison of the lengths of the developed radial cracks showed that ion implantation leads to a reaction in cracking. The observed effects are assigned to radiation induced structural changes of the ceramic. Ion bombardment leads to radiation damage and formation of compressive stress. In case of tantalum implantation, the implanted near-surface zone becomes amorphous. These effects make the ceramic more resistant to fracture. (orig.)

Double-strand breaks in genome-sized DNA caused by mechanical stress under mixing: Quantitative evaluation through single-molecule observation

Science.gov (United States)

Kikuchi, Hayato; Nose, Keiji; Yoshikawa, Yuko; Yoshikawa, Kenichi

2018-06-01

It is becoming increasingly apparent that changes in the higher-order structure of genome-sized DNA molecules of more than several tens kbp play important roles in the self-control of genome activity in living cells. Unfortunately, it has been rather difficult to prepare genome-sized DNA molecules without damage or fragmentation. Here, we evaluated the degree of double-strand breaks (DSBs) caused by mechanical mixing by single-molecule observation with fluorescence microscopy. The results show that DNA breaks are most significant for the first second after the initiation of mechanical agitation. Based on such observation, we propose a novel mixing procedure to significantly decrease DSBs.

Centering and alignment device of a fuel assembling under a heart upper sheet of a pressure water nuclear reactor and centering piece replacement process

International Nuclear Information System (INIS)

Bougis, J.C.

1994-01-01

The crossing opening of the heart upper sheet contains a central part and two end parts of which diameter is higher than the central part one. The centering piece contains a head putting down, thanks to a support part, on a retaining of the opening, a centering and positioning smooth part and a threaded part. The device also contains a nut screwed on the threaded part of the centering piece so far as to come supporting on a retaining of the opening. The nut is made not unscrewed thanks to a stopping washer soldered inside the end part of the crossing opening. (Author). 3 figs., 5 refs

Cohabitants' perspective on housing adaptations: a piece of the puzzle.

Science.gov (United States)

Granbom, Marianne; Taei, Afsaneh; Ekstam, Lisa

2017-12-01

As part of the Swedish state-funded healthcare system, housing adaptations are used to promote safe and independent living for disabled people in ordinary housing through the elimination of physical environmental barriers in the home. The aim of this study was to describe the cohabitants' expectations and experiences of how a housing adaptation, intended for the partner, would impact their everyday life. In-depth interviews were conducted with cohabitants of nine people applying for a housing adaptation, initially at the time of the application and then again 3 months after the housing adaptation was installed. A longitudinal analysis was performed including analysis procedures from Grounded Theory. The findings revealed the expectations and experiences in four categories: partners' activities and independence; cohabitants' everyday activities and caregiving; couples' shared recreational/leisure activities; and housing decisions. A core category putting the intervention into perspective was called 'Housing adaptations - A piece of the puzzle'. From the cohabitants' perspective, new insights on housing adaptations emerged, which are important to consider when planning and carrying out successful housing adaptations. © 2017 Nordic College of Caring Science.

Single-molecule magnetism in three related {Co(III)2Dy(III)2}-acetylacetonate complexes with multiple relaxation mechanisms.

Science.gov (United States)

Langley, Stuart K; Chilton, Nicholas F; Moubaraki, Boujemaa; Murray, Keith S

2013-06-17

Three new heterometallic complexes with formulas of [Dy(III)2Co(III)2(OMe)2(teaH)2(acac)4(NO3)2] (1), [Dy(III)2Co(III)2(OH)2(teaH)2(acac)4(NO3)2]·4H2O (2), and [Dy(III)2Co(III)2(OMe)2(mdea)2(acac)4(NO3)2] (3) were characterized by single-crystal X-ray diffraction and by dc and ac magnetic susceptibility measurements. All three complexes have an identical "butterfly"-type metallic core that consists of two Dy(III) ions occupying the "body" position and two diamagnetic low-spin Co(III) ions occupying the outer "wing-tips". Each complex displays single-molecule magnet (SMM) behavior in zero applied magnetic field, with thermally activated anisotropy barriers of 27, 28, and 38 K above 7.5 K for 1-3, respectively, as well as observing a temperature-independent mechanism of relaxation below 5 K for 1 and 2 and at 3 K for 3, indicating fast quantum tunneling of magnetization (QTM). A second, faster thermally activated relaxation mechanism may also be active under a zero applied dc field as derived from the Cole-Cole data. Interestingly, these complexes demonstrate further relaxation modes that are strongly dependent upon the application of a static dc magnetic field. Dilution experiments that were performed on 1, in the {Y(III)2Co(III)2} diamagnetic analog, show that the slow magnetic relaxation is of a single-ion origin, but it was found that the neighboring ion also plays an important role in the overall relaxation dynamics.

A Nanoindentation Study of the Plastic Deformation and Fracture Mechanisms in Single-Crystalline CaFe2As2

Science.gov (United States)

Frawley, Keara G.; Bakst, Ian; Sypek, John T.; Vijayan, Sriram; Weinberger, Christopher R.; Canfield, Paul C.; Aindow, Mark; Lee, Seok-Woo

2018-04-01

The plastic deformation and fracture mechanisms in single-crystalline CaFe2As2 has been studied using nanoindentation and density functional theory simulations. CaFe2As2 single crystals were grown in a Sn-flux, resulting in homogeneous and nearly defect-free crystals. Nanoindentation along the [001] direction produces strain bursts, radial cracking, and lateral cracking. Ideal cleavage simulations along the [001] and [100] directions using density functional theory calculations revealed that cleavage along the [001] direction requires a much lower stress than cleavage along the [100] direction. This strong anisotropy of cleavage strength implies that CaFe2As2 has an atomic-scale layered structure, which typically exhibits lateral cracking during nanoindentation. This special layered structure results from weak atomic bonding between the (001) Ca and Fe2As2 layers.

Determination of capacity of single-toggle jaw crusher, taking into account parameters of kinematics of its working mechanism

Science.gov (United States)

Golikov, N. S.; Timofeev, I. P.

2018-05-01

Efficiency increase of jaw crushers makes the foundation of rational kinematics and stiffening of the elements of the machine possible. Foundation of rational kinematics includes establishment of connection between operation mode parameters of the crusher and its technical characteristics. The main purpose of this research is just to establish such a connection. Therefore this article shows analytical procedure of getting connection between operation mode parameters of the crusher and its capacity. Theoretical, empirical and semi-empirical methods of capacity determination of a single-toggle jaw crusher are given, taking into account physico-mechanical properties of crushed material and kinematics of the working mechanism. When developing a mathematical model, the method of closed vector polygons by V. A. Zinoviev was used. The expressions obtained in the article give an opportunity to solve important scientific and technical problems, connected with finding the rational kinematics of the jaw crusher mechanism, carrying out a comparative assessment of different crushers and giving the recommendations about updating the available jaw crushers.

Mechanics of the brain: perspectives, challenges, and opportunities.

Science.gov (United States)

Goriely, Alain; Geers, Marc G D; Holzapfel, Gerhard A; Jayamohan, Jayaratnam; Jérusalem, Antoine; Sivaloganathan, Sivabal; Squier, Waney; van Dommelen, Johannes A W; Waters, Sarah; Kuhl, Ellen

2015-10-01

The human brain is the continuous subject of extensive investigation aimed at understanding its behavior and function. Despite a clear evidence that mechanical factors play an important role in regulating brain activity, current research efforts focus mainly on the biochemical or electrophysiological activity of the brain. Here, we show that classical mechanical concepts including deformations, stretch, strain, strain rate, pressure, and stress play a crucial role in modulating both brain form and brain function. This opinion piece synthesizes expertise in applied mathematics, solid and fluid mechanics, biomechanics, experimentation, material sciences, neuropathology, and neurosurgery to address today's open questions at the forefront of neuromechanics. We critically review the current literature and discuss challenges related to neurodevelopment, cerebral edema, lissencephaly, polymicrogyria, hydrocephaly, craniectomy, spinal cord injury, tumor growth, traumatic brain injury, and shaken baby syndrome. The multi-disciplinary analysis of these various phenomena and pathologies presents new opportunities and suggests that mechanical modeling is a central tool to bridge the scales by synthesizing information from the molecular via the cellular and tissue all the way to the organ level.

Performance evaluation of CPF shredder type mechanical crusher with simulated core fuel pin

International Nuclear Information System (INIS)

Nakahara, Masaumi; Sano, Yuichi; Aose, Shin-ichi

2006-12-01

In the advanced aqueous reprocessing system, powder fuel dissolution has been investigated, which is quite effective on the dissolution for highly concentrated solution. As one of the effective means that powder the irradiated MOX fuel, we have been developing shredder type mechanical crusher. This apparatus can automatically crush the sheared fuel pieces by twin-shaft disk blades, powder the crushed fragments by disk blades and screen blade, and recover the powdered fuel. The shredder type mechanical crusher was developed for using in a hot cell in Chemical Processing Facility, and the first crush experiment with this crusher was carried out at July 2004 using the simulated core fuel pin. This experiment showed that the crushed fragments could not be grinded efficiency because screen blade vibrated up and down during the operation. Additionally, the strength of screen blade block was insufficient to crush the sheared fuel pieces stably. Therefore, about 70% of fuel was recovered in maximum. Based on the results of the first experiment, screen blade was fixed up mainly and the second experiment was carried out with improved apparatus at September 2005. In this experiment, about 96% of fuel could be recovered in maximum because screen blade was stable during the operation. (J.P.N.)

Impact of Fruit Piece Structure in Yogurts on the Dynamics of Aroma Release and Sensory Perception

Directory of Open Access Journals (Sweden)

Isabelle Souchon

2013-05-01

Full Text Available The aim of this work was to gain insight into the effect of food formulation on aroma release and perception, both of which playing an important role in food appreciation. The quality and quantity of retronasal aroma released during food consumption affect the exposure time of olfactory receptors to aroma stimuli, which can influence nutritional and hedonic characteristics, as well as consumption behaviors. In yogurts, fruit preparation formulation can be a key factor to modulate aroma stimulation. In this context, the impact of size and hardness of fruit pieces in fat-free pear yogurts was studied. Proton Transfer Reaction-Mass Spectrometry (PTR-MS was used to allow sensitive and on-line monitoring of volatile odorous compound release in the breath during consumption. In parallel, a trained panel used sensory profile and Temporal Dominance of Sensations (TDS methods to characterize yogurt sensory properties and their dynamic changes during consumption. Results showed that the size of pear pieces had few effects on aroma release and perception of yogurts, whereas fruit hardness significantly influenced them. Despite the fact that yogurts presented short and similar residence times in the mouth, this study showed that fruit preparation could be an interesting formulation factor to enhance exposure time to stimuli and thus modify food consumption behaviors. These results could be taken into account to formulate new products that integrate both nutritional and sensory criteria.

Characteristics of dielectric properties and conduction mechanism of TlInS2:Cu single crystals

Science.gov (United States)

El-Nahass, M. M.; Ali, H. A. M.; El-Zaidia, E. F. M.

2013-12-01

Single crystals of TlInS2:Cu were grown by the modified Bridgman method. The dielectric behavior of TlInS2:Cu was investigated using the impedance spectroscopy technique. The real (ε1), imaginary (ε2) parts of complex dielectric permittivity and ac conductivity were measured in the frequency range (42-2×105) Hz with a variation of temperature in the range from 291 K to 483 K. The impedance data were presented in Nyquist diagrams for different temperatures. The frequency dependence of σtot (ω) follows the Jonscher's universal dynamic law with the relation σtot (ω)=σdc+Aωs, (where s is the frequency exponent). The mechanism of the ac charge transport across the layers of TlInS2:Cu single crystals was referred to the hopping over localized states near the Fermi level. The examined system exhibits temperature dependence of σac (ω), which showed a linear increase with the increase in temperature at different frequencies. Some parameters were calculated as: the density of localized states near the Fermi level, NF, the average time of charge carrier hopping between localized states, τ, and the average hopping distance, R.

Atomic structures and mechanical properties of single-crystal GaN nanotubes

International Nuclear Information System (INIS)

Xu, B.; Lu, A.J.; Pan, B.C.; Yu, Q.X.

2005-01-01

An approach is proposed to theoretically construct a realistic single-crystal GaN nanotube at atomic scale. The generated atomic structures of the single-crystal GaN nanotubes match the structural aspects from experiment very well. Our energetic calculations show that a single-crystal GaN nanotube with [100]-oriented lateral facets is more stable than that with [110]-oriented lateral facets, when they have around the same wall thickness. For a specified orientation of the lateral facets on the single-crystal GaN nanotubes, the energetic stabilities of the tubes obey a P rule, in which P is the ratio of the number of four-coordinated atoms to the number of three-coordinated atoms. Furthermore, the Young's modulus of the considered GaN nanotubes decrease with increasing the ratio of the number of bulk atoms to the number of surface atoms in each type of tube. Our calculations and analysis demonstrate that the surface effect of a single-crystal nanotube enhances its Young's modulus significantly

A case of radiation enteritis with perforated peritonitis caused by a piece of eggshell

International Nuclear Information System (INIS)

Kitamura, Hirotaka; Maeda, Kazuya; Miyanaga, Tamonn; Doden, Kenji; Hattori, Masakazu; Hashizume, Yasuo

2011-01-01

The patient was a woman in her sixties who had received radiation therapy for cancer of uterine cervix 7 years earlier and had been suffering from diarrhea for these several years. The patient was seen at our emergency clinic because of a 5 hour-history of lower abdominal pain at the beginning of July 2010. An abdominal CT scan showed free air and ascites. A high density structure 1.5 cm in size was identified within the small intestine, but its relation with the perforation was obscure. Emergency operation was done with the most likely diagnosis of intestinal perforation and general peritonitis. When the lower abdomen was opened by midline incision, about 200 ml of cloudy ascites was observed and the ileum became white in color and hard resulting from the radiation therapy. A perforation was identified in the ileum about 15 cm distant from the ileocecal valve, and a 1.5-cm sized thin and hard material was palpated within the intestine at the same portion. Ilececal resection including the perforated portion was performed and functional end-to-end anastomosis was made at a grossly normal area. There was a piece of eggshell 1.5-cm in size in the perforated portion in the resected specimen. From this together with histopathologial findings, perforation of the small intestine caused by a piece of eggshell associated with radiation enteritis was finally diagnosed. Small bowel perforation must be kept in mind as a possible late complication of radiation therapy, however, no cases of small bowel perforation caused by eggshell have been reported so far. This rare case is reported here, with a review of the literature. (author)

Mechanical Design and Manufacturing Preparation of Loading Unloading Irradiation Facility in Reflector Irradiation Position

International Nuclear Information System (INIS)

Hasibuan, Djaruddin

2004-01-01

Base on planning to increase of the irradiation service quality in Multi purpose Reactor-GAS, the mechanical design and manufacturing of the (n,γ) irradiation facility has been done. The designed of (n,γ) irradiation facility is a new facility in Multi purpose Reactor-GAS. The design doing by design of stringer, guide bar and hanger. By the design installation, the continuous irradiation service of non fission reaction will be easy to be done without reactor shut down. The design of the facility needs 3 pieces Al pipe by 36 x 1.5 mm, a peace of Al round bar by 80 mm diameter and a piece of Al plate by 20 x 60 x 0.2 mm for the stringer and guide bar manufacturing. By the building of non fission irradiation facility in the reflector irradiation position, will make the irradiation service to be increased. (author)

Strength and Failure Mechanism of Composite-Steel Adhesive Bond Single Lap Joints

Directory of Open Access Journals (Sweden)

Kai Wei

2018-01-01

Full Text Available Carbon fiber-reinforced plastics- (CFRP- steel single lap joints with regard to tensile loading with two levels of adhesives and four levels of overlap lengths were experimentally analyzed and numerically simulated. Both joint strength and failure mechanism were found to be highly dependent on adhesive type and overlap length. Joints with 7779 structural adhesive were more ductile and produced about 2-3 kN higher failure load than MA830 structural adhesive. Failure load with the two adhesives increased about 147 N and 176 N, respectively, with increasing 1 mm of the overlap length. Cohesion failure was observed in both types of adhesive joints. As the overlap length increased, interface failure appeared solely on the edge of the overlap in 7779 adhesive joints. Finite element analysis (FEA results revealed that peel and shear stress distributions were nonuniform, which were less severe as overlap length increased. Severe stress concentration was observed on the overlap edge, and shear failure of the adhesive was the main reason for the adhesive failure.

Insulator-protected mechanically controlled break junctions for measuring single-molecule conductance in aqueous environments

Energy Technology Data Exchange (ETDEWEB)

Muthusubramanian, N.; Zant, H. S. J. van der [Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Galan, E.; Maity, C.; Eelkema, R.; Grozema, F. C. [Department of Chemical Engineering, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft (Netherlands)

2016-07-04

We present a method to fabricate insulated gold mechanically controlled break junctions (MCBJ) by coating the metal with a thin layer of aluminum oxide using plasma enhanced atomic layer deposition. The Al{sub 2}O{sub 3} thickness deposited on the MCBJ devices was varied from 2 to 15 nm to test the suppression of leakage currents in deionized water and phosphate buffered saline. Junctions coated with a 15 nm thick oxide layer yielded atomically sharp electrodes and negligible conductance counts in the range of 1 to 10{sup −4} G{sub 0} (1 G{sub 0} = 77 μS), where single-molecule conductances are commonly observed. The insulated devices were used to measure the conductance of an amphiphilic oligophenylene ethynylene derivative in deionized water.

The role of prosthetic abutment material on the stress distribution in a maxillary single implant-supported fixed prosthesis

Energy Technology Data Exchange (ETDEWEB)

Peixoto, Hugo Eduardo, E-mail: hugo.e.peixoto@hotmail.com [Implantology Team, Latin American Institute of Research and Education in Dentistry, Curitiba, Paraná (Brazil); Bordin, Dimorvan, E-mail: dimorvan_bordin@hotmail.com [Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903 (Brazil); Del Bel Cury, Altair A., E-mail: altcury@fop.unicamp.br [Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903 (Brazil); Silva, Wander José da, E-mail: wanderjose@fop.unicamp.br [Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903 (Brazil); Faot, Fernanda, E-mail: fernanda.faot@gmail.com [Department of Restorative Dentistry, School of Dentistry, Federal University of Pelotas, Gonçalves Chaves, 457, 2nd floor, Pelotas, Rio Grande do Sul 96015-560 (Brazil)

2016-08-01

Purpose: Evaluate the influence of abutment's material and geometry on stress distribution in a single implant-supported prosthesis. Materials and Methods: Three-dimensional models were made based on tomographic slices of the upper middle incisor area, in which a morse taper implant was positioned and a titanium (Ti) or zirconia (ZrN) universal abutments was installed. The commercially available geometry of titanium (T) and zirconia (Z) abutments were used to draw two models, TM1 and ZM1 respectively, which served as control groups. These models were compared with 2 experimental groups were the mechanical properties of Z were applied to the titanium abutment (TM2) and vice versa for the zirconia abutment (ZM2). Subsequently, loading was simulated in two steps, starting with a preload phase, calculated with the respective friction coefficients of each materials, followed by a combined preload and chewing force. The maximum von Mises stress was described. Data were analyzed by two-way ANOVA that considered material composition, geometry and loading (p < 0.05). Results: Titanium and zirconia abutments showed similar von Mises stresses in the mechanical part of the four models. The area with the highest concentration of stress was the screw thread, following by the screw body. The highest stress levels occurred in screw thread was observed during the preloading phase in the ZM1 model (931 MPa); and during the combined loading in the TM1 model (965 MPa). Statistically significant differences were observed for loading, the material × loading interaction, and the loading × geometry interaction (p < 0.05). Preloading contributed for 77.89% of the stress (p < 0.05). There were no statistically significant differences to the other factors (p > 0.05). Conclusion: The screw was the piece most intensely affected, mainly through the preload force, independent of the abutment's material. - Highlights: • The abutment's screw was the most impaired piece of the

SSC [Superconducting Super Collider] magnet mechanical interconnections

International Nuclear Information System (INIS)

Bossert, R.C.; Niemann, R.C.; Carson, J.A.; Ramstein, W.L.; Reynolds, M.P.; Engler, N.H.

1989-03-01

Installation of superconducting accelerator dipole and quadrupole magnets and spool pieces in the SSC tunnel requires the interconnection of the cryostats. The connections are both of an electrical and mechanical nature. The details of the mechanical connections are presented. The connections include piping, thermal shields and insulation. There are seven piping systems to be connected. These systems must carry cryogenic fluids at various pressures or maintain vacuum and must be consistently leak tight. The interconnection region must be able to expand and contract as magnets change in length while cooling and warming. The heat leak characteristics of the interconnection region must be comparable to that of the body of the magnet. Rapid assembly and disassembly is required. The magnet cryostat development program is discussed. Results of quality control testing are reported. Results of making full scale interconnections under magnet test situations are reviewed. 11 figs., 4 tabs

SPECIAL TRAITS OF MANIFESTATION OF DEFENCIVE MECHANISMS DURING DEVELOPMENT OF SELF-ATTITUDE OF TEENAGERS FROM FULL AND SINGLE-PARENT FAMILIES

Directory of Open Access Journals (Sweden)

A. E. Melojan

2015-01-01

Full Text Available The article is devoted to one of the problems of personality development of today’s teenagers pertaining to their self-attitude and psychological defence. It presents the results of a comparative analysis of self-attitude development specifics and manifestation of defence mechanisms in teenagers from full and single-parent families as well as special traits of interconnection of self-attitude main components and some types of psychological defence that are typical for them. Better well-being and greater disposition to approve of themselves has been revealed among those raised in full families as against a tendency to self-disparagement, besides the more intensive use of psychological defence, of their peers from single-parent families. It has been established that family structure defined by the principle “full” - “single-parent” is an important factor of self-attitude development and manifestation of psychological defence in teenagers.

Structural Optimization of an Offshore Wind Turbines Transition Pieces for Bucket Foundations

DEFF Research Database (Denmark)

Nezhentseva, Anastasia; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

Traditionally, offshore constructions are made of steel. The focus of this paper is optimization of a transition piece (TP) connecting the offshore wind turbine column with a suction bucket foundation. Suction caissons, typically used for shallow water depths, have been proved to be adequate...... in residual soil conditions for depths up to approximately 40 m. The existing design practice is limited to the use of steel-flange-reinforced shear panels. Desirable outcome is proposal of an alternative material which does not require extensive welding work. Compact reinforced composite (CRC) is suggested...... curved segments have been introduced between the conical part and the tubular parts of the structure. While the minimum amount of steel and concrete was required for the composite CRC–steel shell model, the pure CRC model appeared to be the least sensitive to geometrical imperfections, corresponding...

Quantifying cellular mechanics and adhesion in renal tubular injury using single cell force spectroscopy.

Science.gov (United States)

Siamantouras, Eleftherios; Hills, Claire E; Squires, Paul E; Liu, Kuo-Kang

2016-05-01

Tubulointerstitial fibrosis represents the major underlying pathology of diabetic nephropathy where loss of cell-to-cell adhesion is a critical step. To date, research has predominantly focussed on the loss of cell surface molecular binding events that include altered protein ligation. In the current study, atomic force microscopy single cell force spectroscopy (AFM-SCFS) was used to quantify changes in cellular stiffness and cell adhesion in TGF-β1 treated kidney cells of the human proximal tubule (HK2). AFM indentation of TGF-β1 treated HK2 cells showed a significant increase (42%) in the elastic modulus (stiffness) compared to control. Fluorescence microscopy confirmed that increased cell stiffness is accompanied by reorganization of the cytoskeleton. The corresponding changes in stiffness, due to F-actin rearrangement, affected the work of detachment by changing the separation distance between two adherent cells. Overall, our novel data quantitatively demonstrate a correlation between cellular elasticity, adhesion and early morphologic/phenotypic changes associated with tubular injury. Diabetes affects many patients worldwide. One of the long term problems is diabetic nephropathy. Here, the authors utilized atomic force microscopy single cell force spectroscopy (AFM- SCFS) to study cellular stiffness and cell adhesion after TGF1 treatment in human proximal tubule kidney cells. The findings would help further understand the overall disease mechanism in diabetic patients. Copyright © 2015 Elsevier Inc. All rights reserved.

A self-calibration method in single-axis rotational inertial navigation system with rotating mechanism

Science.gov (United States)

Chen, Yuanpei; Wang, Lingcao; Li, Kui

2017-10-01

Rotary inertial navigation modulation mechanism can greatly improve the inertial navigation system (INS) accuracy through the rotation. Based on the single-axis rotational inertial navigation system (RINS), a self-calibration method is put forward. The whole system is applied with the rotation modulation technique so that whole inertial measurement unit (IMU) of system can rotate around the motor shaft without any external input. In the process of modulation, some important errors can be decoupled. Coupled with the initial position information and attitude information of the system as the reference, the velocity errors and attitude errors in the rotation are used as measurement to perform Kalman filtering to estimate part of important errors of the system after which the errors can be compensated into the system. The simulation results show that the method can complete the self-calibration of the single-axis RINS in 15 minutes and estimate gyro drifts of three-axis, the installation error angle of the IMU and the scale factor error of the gyro on z-axis. The calibration accuracy of optic gyro drifts could be about 0.003°/h (1σ) as well as the scale factor error could be about 1 parts per million (1σ). The errors estimate reaches the system requirements which can effectively improve the longtime navigation accuracy of the vehicle or the boat.

Printed thermoplastic modular piece, P.T.M.P. = Piezas termoplásticas modulares, P.T.M.P.

Directory of Open Access Journals (Sweden)

Sandra Moyano Sanz

2018-04-01

Full Text Available This research tries to design a modular part suitable for construction, with new materials and manufacturing processes. Polymers and 3D printing are the key elements in the process. It is about implanting a new model of modular part that is able to replace the conventional brick. With this research, we want to make known the new construction processes derived from 3D printing and how we can improve the existing technology. The main objective is to design a modular part, using additive manufacturing systems and plastic materials. Then we are going to determine the physical characteristics that the pieces must have, and the geometric possibilities that the manufacturing process allows us, as well as the materials that the pieces will be made. These pieces will be subject to all the actual tests to ceramic pieces, according to the current standard. Additionally, we will analyze the results obtained and compare them with an expensive ceramic brick to assess the advantages obtained. Finally, we will determine some conclusions derived from these investigations, and propose new study proposals. With this research, we intend to demonstrate that, although conventional brick are basic elements of construction and fulfils its functions perfectly, it is time to adapt the new technologies to the constructive methods. Resumen Este estudio trata de diseñar una pieza modular apropiada para la construcción mediante nuevos procesos de producción y nuevos materiales. Los polímeros y la impresión 3D son los elementos clave del proceso. Además, se estudia implantar un nuevo modelo de pieza modular que sea capaz de sustituir al ladrillo convencional. Con esta investigación queremos divulgar los nuevos procesos asociados a la impresión 3D y como podemos mejorar la tecnología existente. El objetivo principal es diseñar una pieza modular, usando sistemas de fabricación aditiva y materiales plásticos. Posteriormente vamos a determinar las características f

The measurement of Ksub(IC) in single crystal SiC using the indentation method

International Nuclear Information System (INIS)

Henshall, J.L.; Brookes, C.A.

1985-01-01

The present work has concentrated on investigating the underlying fracture toughness behaviour of SiC single crystals. This material was chosen because of the commercial importance of the various polycrystalline forms of SiC and the relative ready availability of reasonably sized single crystals. This study has examined the feasibility of using the indentation technique to determine Ksub(IC) in SiC single crystals. This requires much more less complex experimentation and also affords the possibility of being able to use this method to study the orientation dependence of Ksub(IC) in a similar manner to that used to investigate anisotropy in indentation hardness behaviour. A single crystal of 6H-SiC was used for all the hardness and conventional Ksub(IC) results reported here. The particular polytype and orientation were determined using the Laue X-ray method. All the measurements were made under ambient conditions. Three-point bend tests, with a 6 mm span on single edge notched beams, SENB, orientated such that the plane of the notch was brace 112-bar0 brace and the crack propagation direction were used for the conventional Ksub(IC) tests. The hardness indentations were all made on one particular SENB test piece after it had been fractured. The results are discussed. (author)

A new and simple extraction technique for rectal foreign bodies: removing by cutting into small pieces

OpenAIRE

Abbas Aras; Mehmet Karabulut; Osman Kones; Kaplan Baha Temizgonul; Halil Alis

2014-01-01

The purposes of insertion and types of foreign bodies in rectum show great variation. Rectal foreign bodies need to be removed without giving damage to intestinal wall and this should be done in the easiest possible way. We have reported a new and a simple technique. It is easy to apply and safe. A patient was admitted to our clinic with a rectal foreign body (radish) which was successfully removed by cutting it into small pieces. We conclude that different kinds of rectal foreign bodies, esp...

A polypeptide-DNA hybrid with selective linking capability applied to single molecule nano-mechanical measurements using optical tweezers.

Directory of Open Access Journals (Sweden)

Fatemeh Moayed

Full Text Available Many applications in biosensing, biomaterial engineering and single molecule biophysics require multiple non-covalent linkages between DNA, protein molecules, and surfaces that are specific yet strong. Here, we present a novel method to join proteins and dsDNA molecule at their ends, in an efficient, rapid and specific manner, based on the recently developed linkage between the protein StrepTactin (STN and the peptide StrepTag II (ST. We introduce a two-step approach, in which we first construct a hybrid between DNA and a tandem of two STs peptides (tST. In a second step, this hybrid is linked to polystyrene bead surfaces and Maltose Binding Protein (MBP using STN. Furthermore, we show the STN-tST linkage is more stable against forces applied by optical tweezers than the commonly used biotin-Streptavidin (STV linkage. It can be used in conjunction with Neutravidin (NTV-biotin linkages to form DNA tethers that can sustain applied forces above 65 pN for tens of minutes in a quarter of the cases. The method is general and can be applied to construct other surface-DNA and protein-DNA hybrids. The reversibility, high mechanical stability and specificity provided by this linking procedure make it highly suitable for single molecule mechanical studies, as well as biosensing and lab on chip applications.

Laparoscopic female sterilisation by a single port through monitor--a better alternative.

Science.gov (United States)

Sewta, Rajender Singh

2011-04-01

Female sterilisation by tubal occlusion method by laparocator is most widely used and accepted technique of all family planning measures all over the world. After the development of laparoscopic surgery in all faculties of surgery by monitor, now laparoscopic female sterilisation has been developed to do under monitor control by two ports--one for laparoscope and second for ring applicator. But the technique has been modified using single port with monitor through laparocator in which camera is fitted on the eye piece of laparocator (the same laparocator which is commonly used in camps without monitor since a long time in India). In this study over a period of about 2 years, a total 2011 cases were operated upon. In this study, I used camera and monitor through a single port by laparocator to visualise as well as to apply ring on fallopian tubes. The result is excellent and is a better alternative to conventional laparoscopic sterilisation and double puncture technique through camera--which give two scars and an extra assistant is required. However, there was no failure and the strain on surgeon's eye was minimum. Single port is much easier, safe, equally effective and better acceptable method.

Nucleation Mechanisms of Aromatic Polyesters, PET, PBT, and PEN, on Single-Wall Carbon Nanotubes: Early Nucleation Stages

Directory of Open Access Journals (Sweden)

Adriana Espinoza-Martínez

2012-01-01

Full Text Available Nucleation mechanisms of poly(ethylene terephthalate (PET, poly(butylene terephthalate (PBT, and poly(ethylene naphthalate (PEN on single-wall carbon nanotubes (SWNTs are proposed, based on experimental evidence, theoretical epitaxy analysis, and semiempirical quantum chemical calculations. In order to elucidate early nucleation stages polyester-coated nanotubes were obtained from highly diluted solutions. High-resolution transmission electron microscopy (HRTEM revealed helical morphologies for PET/SWNTs and PEN/SWNTs and the formation of lobules with different orientations for PBT/SWNTs. To explain the morphological behavior one model was proposed based on crystallographic interactions, that is, epitaxy. Theoretical epitaxy calculations indicated that epitaxy is not possible from the strict epitaxy point of view. Instead, aromatic self-assembly mechanism was proposed based on π-π interactions and the chirality of the nanotube. It was proposed that the mechanism implies two steps to produce helical or lobular morphologies with different orientations. In the first step polymer chains were approached, aligned parallel to the nanotube axis and adsorbed due to electrostatic interactions and the flexibility of the molecule. However, due to π-π interactions between the aromatic rings of the polymer and the nanotube, in the second step chains reoriented on the nanotube surface depending on the chirality of the nanotube. The mechanism was supported by semi-empirical calculations.

Toward mechanical systems biology in bone.

Science.gov (United States)

Trüssel, Andreas; Müller, Ralph; Webster, Duncan

2012-11-01

Cyclic mechanical loading is perhaps the most important physiological factor regulating bone mass and shape in a way which balances optimal strength with minimal weight. This bone adaptation process spans multiple length and time scales. Forces resulting from physiological exercise at the organ scale are sensed at the cellular scale by osteocytes, which reside inside the bone matrix. Via biochemical pathways, osteocytes orchestrate the local remodeling action of osteoblasts (bone formation) and osteoclasts (bone resorption). Together these local adaptive remodeling activities sum up to strengthen bone globally at the organ scale. To resolve the underlying mechanisms it is required to identify and quantify both cause and effect across the different scales. Progress has been made at the different scales experimentally. Computational models of bone adaptation have been developed to piece together various experimental observations at the different scales into coherent and plausible mechanisms. However additional quantitative experimental validation is still required to build upon the insights which have already been achieved. In this review we discuss emerging as well as state of the art experimental and computational techniques and how they might be used in a mechanical systems biology approach to further our understanding of the mechanisms governing load induced bone adaptation, i.e., ways are outlined in which experimental and computational approaches could be coupled, in a quantitative manner to create more reliable multiscale models of bone.

Mechanics of machinery

CERN Document Server

Mostafa, Mahmoud A

2012-01-01

MechanismsDefinitions Degrees of Freedom of Planar Mechanisms Four-Revolute-Pairs Chains Single-Slider Chain Double-Slider Mechanisms Mechanisms with Higher Pairs Compound Mechanisms Special Mechanisms Analytical Position Analysis of Mechanisms Velocities and AccelerationsAbsolute Plane Motion of a Particle Relative Motion Applications to Common Links Analysis of Mechanisms: Graphical Method Method of Instantaneous Centers for Determining the VelocitiesAnalytical Analysis CamsIntroduction Types of Cams Modes of Input/Output Motion Follower Configurations Classes of Cams Spur GearsIntroduction

Studies Regarding Design and Optimization of Mechanisms Using Modern Techniques of CAD and CAE

Directory of Open Access Journals (Sweden)

Marius Tufoi

2010-01-01

Full Text Available The paper presents applications of modern techniques of CAD (Computer Aided Design and CAE (Computer Aided Engineering to design and optimize the mechanisms used in mechanical engineering. The use exemplification of these techniques was achieved by designing and optimizing parts of a drawing installation for horizontal continuous casting of metals. By applying these design methods and using finite element method at simulations on designed mechanisms results a number of advantages over traditional methods of drawing and design: speed in drawing, design and optimization of parts and mechanisms, kinematic analysis option, kinetostatic and dynamic through simulation, without requiring physical realization of the part or mechanism, the determination by finite element method of tension, elongations, travel and safety factor and the possibility of optimization for these sizes to ensure the mechanical strength of each piece separately. Achieving these studies was possible using SolidWorks 2009 software suite.

Crystalline perfection and mechanical investigations on vertical Bridgman grown Bismuth telluride (Bi_2Te_3) single crystals for thermoelectric applications

International Nuclear Information System (INIS)

Krishna, Anuj; Vijayan, N.; Singh, Budhendra; Thukral, Kanika; Maurya, K.K.

2016-01-01

High efficiency thermoelectric materials plays a vital role in power generation and refrigeration applications. Bismuth telluride (Bi_2Te_3) is one among them. In the present work single crystal of bismuth telluride was grown using vertical Bridgman technique. The phase of grown crystals was analysed using a powder X-ray diffractometer. Quality of the grown crystal was assessed by using high resolution X-ray diffractometer and observed that it is fairly good. Further mechanical investigations on grown crystal was carried out using nano-indentation technique and various mechanical properties like hardness, stiffness and Young’s modulus were evaluated. Observed results clearly indicate its suitability for thermoelectric applications.

One-single physical exercise session after object recognition learning promotes memory persistence through hippocampal noradrenergic mechanisms.

Science.gov (United States)

da Silva de Vargas, Liane; Neves, Ben-Hur Souto das; Roehrs, Rafael; Izquierdo, Iván; Mello-Carpes, Pâmela

2017-06-30

Previously we showed the involvement of the hippocampal noradrenergic system in the consolidation and persistence of object recognition (OR) memory. Here we show that one-single physical exercise session performed immediately after learning promotes OR memory persistence and increases norepinephrine levels in the hippocampus. Additionally, effects of exercise on memory are avoided by an intra-hippocampal beta-adrenergic antagonist infusion. Taken together, these results suggest that exercise effects on memory can be related to noradrenergic mechanisms and acute physical exercise can be a non-pharmacological intervention to assist memory consolidation and persistence, with few or no side effects. Copyright © 2017 Elsevier B.V. All rights reserved.

Equivalent mechanical parameters of oscillating rotary motors used in transport equipment

Directory of Open Access Journals (Sweden)

A. Andziulis

2006-12-01

Full Text Available In various appliances and equipment of sundry transport means there is a lot of diverse mechanisms of periodical movement. So, the various piston or membrane pumps of fuel feeding and lubrication systems, circulation pumps, air and refrigerating coolant compressors, etc. are the typical examples of innovative and well promising application of the oscillating motors. In these cases the moving part of a motor can be directly connected to the working body of driven mechanism without the additional gears. Consequently, the drive can be simplified in design and improved in efficiency and reliability. Application of the oscillating rotary motors, if used in the aforesaid devices, strictly depends on specific properties of mechanical system of a motor aggregated with the driven mechanism and considered as the one-piece unit on the whole. So, this study analyses how the properties of mechanical system, comprised of two moving parts interconnected eccentrically or centrically, can be evaluated by the equivalent rotational inertia, equivalent mass and by equivalent mechanical power factor which, in turn, determine the operating characteristics and basic possibilities of the motor.

Real-time single-molecule tethered particle motion experiments reveal the kinetics and mechanisms of Cre-mediated site-specific recombination

Science.gov (United States)

Fan, Hsiu-Fang

2012-01-01

Tyrosine family recombinases (YRs) are widely utilized in genome engineering systems because they can easily direct DNA rearrangement. Cre recombinases, one of the most commonly used types of YRs, catalyze site-specific recombination between two loxP sites without the need for high-energy cofactors, other accessory proteins or a specific DNA target sequence between the loxP sites. Previous structural, analytical ultracentrifuge and electrophoretic analyses have provided details of the reaction kinetics and mechanisms of Cre recombinase activity; whether there are reaction intermediates or side pathways involved has been left unaddressed. Using tethered particle motion (TPM), the Cre-mediated site-specific recombination process has been delineated, from beginning to end, at the single-molecule level, including the formation of abortive complexes and wayward complexes blocking inactive nucleoprotein complexes from entering the recombination process. Reversibility in the strand-cleavage/-ligation process and the formation of a thermally stable Holliday junction intermediate were observed within the Cre-mediated site-specific recombination process. Rate constants for each elementary step, which explain the overall reaction outcomes under various conditions, were determined. Taking the findings of this study together, they demonstrate the potential of single-molecule methodology as an alternative approach for exploring reaction mechanisms in detail. PMID:22467208

Low level radioactive waste management in New York State all the pieces of the puzzle, but

International Nuclear Information System (INIS)

Gerber, C.A.

1995-01-01

Unlike many other states and compacts, New York not only has a volunteer community, but that community has over three thousand acres of state owned land that was intended for commercial nuclear use. A poll conducted by the Siting Commission indicates that the citizens of New York understand the need for a central monitored disposal facility for LLRW. Hundreds of widely dispersed storage sites are unacceptable to the majority of New Yorkers. New York State has a law requiring the siting and construction of a facility for the permanent disposal of LLRW. The regulations are in place and the Siting Commission has gone through the siting process forward, and should be about finished doing it backwards as the amended state law required. The State Health Department has authorized a $800,000 contract to the National Academy of Science to review the process. The representatives of the Cortland County opponents went on record and already stated that the NAS Study is unacceptable. After fifty million dollars the results are catastrophic. The generators in the state will be forced to store their waste because of the failure by the state to obey it's own law. According to the law, the facility was to be in operation no later than January 1, 1993. While New York State has all the pieces of the LLRW management puzzle on the table, there are many people with political and social agendas ready to knock the pieces onto the floor

Design and Development of a Solar Thermal Collector with Single Axis Solar Tracking Mechanism

Directory of Open Access Journals (Sweden)

Theebhan Mogana

2016-01-01

Full Text Available The solar energy is a source of energy that is abundant in Malaysia and can be easily harvested. However, because of the rotation of the Earth about its axis, it is impossible to harvest the solar energy to the maximum capacity if the solar thermal collector is placed fix to a certain angle. In this research, a solar thermal dish with single axis solar tracking mechanism that will rotate the dish according to the position of the sun in the sky is designed and developed, so that more solar rays can be reflected to a focal point and solar thermal energy can be harvested from the focal point. Data were collected for different weather conditions and performance of the solar thermal collector with a solar tracker were studied and compared with stationary solar thermal collector.

Procedure for the qualification of a manufacturer of ingot iron pieces for application in nuclear power plant components

International Nuclear Information System (INIS)

Rahn, K.M.M.; Jusevicius, E.; Michael, H.

1981-01-01

The process for the qualification of 'Sao Caetano do Sul (Acos Villares S/A)' Plant as manufacturers of ingot iron pieces for application in components of Angra 2 and Angra 3 Nuclear Power Plants, is presented. The qualification was executed by IBQN - Instituto Brasileiro de Qualidade Nuclear - the organ officially in charge of the execution of qualification of suppliers of materials for the nuclear industry. (E.G.) [pt

A Randomised Controlled Trial of the Use of a Piece of Commercial Software for the Acquisition of Reading Skills

Science.gov (United States)

Khan, Muhammad Ahmad; Gorard, Stephen

2012-01-01

We report here the overall results of a cluster randomised controlled trial of the use of computer-aided instruction with 672 Year 7 pupils in 23 secondary school classes in the north of England. A new piece of commercial software, claimed on the basis of publisher testing to be effective in improving reading after just six weeks of use in the…

The transition mechanism from a symmetric single period discharge to a period-doubling discharge in atmospheric helium dielectric-barrier discharge