WorldWideScience

Sample records for current construction engineering

  1. Towards the design of 3D multiscale instructive tissue engineering constructs: Current approaches and trends.

    Science.gov (United States)

    Oliveira, Sara M; Reis, Rui L; Mano, João F

    2015-11-01

    The design of 3D constructs with adequate properties to instruct and guide cells both in vitro and in vivo is one of the major focuses of tissue engineering. Successful tissue regeneration depends on the favorable crosstalk between the supporting structure, the cells and the host tissue so that a balanced matrix production and degradation are achieved. Herein, the major occurring events and players in normal and regenerative tissue are overviewed. These have been inspiring the selection or synthesis of instructive cues to include into the 3D constructs. We further highlight the importance of a multiscale perception of the range of features that can be included on the biomimetic structures. Lastly, we focus on the current and developing tissue-engineering approaches for the preparation of such 3D constructs: top-down, bottom-up and integrative. Bottom-up and integrative approaches present a higher potential for the design of tissue engineering devices with multiscale features and higher biochemical control than top-down strategies, and are the main focus of this review. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Concrete construction engineering handbook

    CERN Document Server

    Nawy, Edward G

    2008-01-01

    Provides coverage of concrete construction engineering and technology. This work features discussions focusing on: the advances in engineered concrete materials; reinforced concrete construction; specialized construction techniques; and, design recommendations for high performance.

  3. Vascularised Tissue Engineering Construct

    Directory of Open Access Journals (Sweden)

    Irza Sukmana

    2012-01-01

    Full Text Available The guidance of endothelial cell organization into a capillary network has been a long-standing challenge in tissue engineering. Some research efforts have been made to develop methods to promote capillary networks inside engineered tissue constructs. Capillary and vascular networks that would mimic blood microvessel function can be used to subsequently facilitate oxygen and nutrient transfer as well as waste removal. Vascularization of engineering tissue construct is one of the most favorable strategies to overpass nutrient and oxygen supply limitation, which is often the major hurdle in developing thick and complex tissue and artificial organ. This paper addresses recent advances and future challenges in developing three-dimensional culture systems to promote tissue construct vascularization allowing mimicking blood microvessel development and function encountered in vivo. Bioreactors systems that have been used to create fully vascularized functional tissue constructs will also be outlined.

  4. Engineering geology of construction

    Energy Technology Data Exchange (ETDEWEB)

    Eddleston, M.; Walthall, S.; Cripps, J.C.; Culshaw, M.G. [eds.] [North West Water Engineering, Risley (United Kingdom)

    1995-12-31

    The book examines, in detail, the input of engineering geologists to the construction sequence on UK and international projects. The book provides an authoritative mix of overviews and detailed case histories. It presents valuable information relating to modern geotechnical construction processes from around the world. The contributions are drawn from a wide variety of projects, including foundations, highways, tunnelling and excavations. The book contains 35 chapters divided into sections headed: introduction; construction of foundations; highway construction; tunnels; excavations and slopes; and the professional engineering geologists. The majority of papers presented at the conference are included plus a series of specially commissioned papers. Four papers have been abstracted separately for the IEA Coal Research CD-ROM.

  5. Constructive Engineering of Simulations

    Science.gov (United States)

    Snyder, Daniel R.; Barsness, Brendan

    2011-01-01

    Joint experimentation that investigates sensor optimization, re-tasking and management has far reaching implications for Department of Defense, Interagency and multinational partners. An adaption of traditional human in the loop (HITL) Modeling and Simulation (M&S) was one approach used to generate the findings necessary to derive and support these implications. Here an entity-based simulation was re-engineered to run on USJFCOM's High Performance Computer (HPC). The HPC was used to support the vast number of constructive runs necessary to produce statistically significant data in a timely manner. Then from the resulting sensitivity analysis, event designers blended the necessary visualization and decision making components into a synthetic environment for the HITL simulations trials. These trials focused on areas where human decision making had the greatest impact on the sensor investigations. Thus, this paper discusses how re-engineering existing M&S for constructive applications can positively influence the design of an associated HITL experiment.

  6. Hydrogels Constructed from Engineered Proteins.

    Science.gov (United States)

    Li, Hongbin; Kong, Na; Laver, Bryce; Liu, Junqiu

    2016-02-24

    Due to their various potential biomedical applications, hydrogels based on engineered proteins have attracted considerable interest. Benefitting from significant progress in recombinant DNA technology and protein engineering/design techniques, the field of protein hydrogels has made amazing progress. The latest progress of hydrogels constructed from engineered recombinant proteins are presented, mainly focused on biorecognition-driven physical hydrogels as well as chemically crosslinked hydrogels. The various bio-recognition based physical crosslinking strategies are discussed, as well as chemical crosslinking chemistries used to engineer protein hydrogels, and protein hydrogels' various biomedical applications. The future perspectives of this fast evolving field of biomaterials are also discussed.

  7. The Current Management Situation and Countermeasures of Construction Engineering Cost%建设工程造价管理现状与应对策略

    Institute of Scientific and Technical Information of China (English)

    黄晓彦

    2014-01-01

    在建设工程的整个过程中,建设工程的造价管理具有重要的影响作用。本文首先介绍了建设工程造价管理的当前现状及存在的问题,然后提出了针对当前建设工程造价管理现状的应对策略,为建设工程的造价管理提供了必要的参考依据。%The construction project cost management plays an important role in the whole process of construction project. This article first introduces the current situation and existing problems of construction project cost management, and then put forward the countermeasures in view of the current con-struction project cost management, in order to provide the necessary reference basis for the construction project cost management.

  8. ENGINEERING BULLETIN: CONSTRUCTED WETLANDS TREATMENT

    Science.gov (United States)

    Constructed wetlands have been demonstrated effective in removing organic, metal, and nutrient elements including nitrogen and phosphorus from municipal wastewaters, mine drainage, industrial effluents, and agricultural runoff. The technology is waste stream-specific, requiring...

  9. Bridge engineering handbook construction and maintenance

    CERN Document Server

    Chen, Wai-Fah

    2014-01-01

    Over 140 experts, 14 countries, and 89 chapters are represented in the second edition of the Bridge Engineering Handbook. This extensive collection highlights bridge engineering specimens from around the world, contains detailed information on bridge engineering, and thoroughly explains the concepts and practical applications surrounding the subject.Published in five books: Fundamentals, Superstructure Design, Substructure Design, Seismic Design, and Construction and Maintenance, this new edition provides numerous worked-out examples that give readers step-by-step design procedures, includes c

  10. Engineering Accomplishments in the Construction of NCSX

    Energy Technology Data Exchange (ETDEWEB)

    G. H. Neilson; P.J. Heitzenroeder; B.E. Nelson; W.T. Reiersen; A. Brooks; T.G. Brown; J.H. Chrzanowski; M.J. Cole; F. Dahlgren; T. Dodson; L.E. Dudek; R.A. Ellis; H.M. Fan; P.J. Fogarty; K.D. Freudenberg; P.L. Goranson; J.H. Harris; M.R. Kalish; G. Labik; J.F. Lyon; N. Pomphrey; C.D. Priniski; S. Raftopoulos; D.J. Rej; W.R. Sands; R.T. Simmons; B.E. Stratton; R.L. Strykowsky; M.E. Viola; D.E. Williamson; M.C. Zarnstorff

    2008-09-01

    The National Compact Stellarator Experiment (NCSX) was designed to test a compact, quasiaxisymmetric stellarator configuration. Flexibility and accurate realization of its complex 3D geometry were key requirements affecting the design and construction. While the project was terminated before completing construction, there were significant engineering accomplishments in design, fabrication, and assembly. The design of the stellarator core device was completed. All of the modular coils, toroidal field coils, and vacuum vessel sectors were fabricated. Critical assembly steps were demonstrated. Engineering advances were made in the application of CAD modeling, structural analysis, and accurate fabrication of complex-shaped components and subassemblies. The engineering accomplishments of the project are summarized

  11. Parafermion Fields Constructed by Current Algebra

    Institute of Scientific and Technical Information of China (English)

    YANGZhan-Ying; SHIKang-Jie; WANGPei; ZHAOLiu

    2004-01-01

    In this letter, the parafermion fields constructed by current algebra are considered. It is proved that there must be a parafermion field with respect to each form of current algebra. We also obtain the corresponding representation and unitary relation of the parafermion field from any current algebra.

  12. Engineering geology for constructional engineers. Ingenieurgeologie fuer Bauingenieure

    Energy Technology Data Exchange (ETDEWEB)

    Klengel, K.J.; Wagenbreth, O.

    1982-01-01

    After a comprehensive review of minerals rocks, endogenic and exogenic processes and an outline of geological history, the authors proceed to discuss the problems of general and applied engineering geology. Central fields of interest are the characteristics of building foundations and changes of these, analysis of foundation soil, and the application of engineering geology in the various branches of constructional engineering. In particular, the engineering-geological aspects of rock mining are stressed as well as the bearing capacity and stability of foundation soil.

  13. Engineering fabrics in transportation construction

    Science.gov (United States)

    Herman, S. C.

    1983-11-01

    The following areas are discussed: treatments for reduction of reflective cracking of asphalt overlays on jointed-concrete pavements in Georgia; laboratory testing of fabric interlayers for asphalt concrete paving: interim report; reflection cracking models: review and laboratory evaluation of engineering fabrics; optimum-depth method for design of fabric-reinforced unsurfaced roads; dynamic test to predict field behavior of filter fabrics used in pavement subdrains; mechanism of geotextile performance in soil-fabric systems for drainage and erosion control; permeability tests of selected filter fabrics for use with a loess-derived alluvium; geotextile filter criteria; use of fabrics for improving the placement of till on peat foundation; geotextile earth-reinforced retaining wall tests: Glenwood Canyon, Colorado; New York State Department of Transportation's experience and guidelines for use of geotextiles; evaluation of two geotextile installations in excess of a decade old; and, long-term in situ properties of geotextiles.

  14. Software engineering the current practice

    CERN Document Server

    Rajlich, Vaclav

    2011-01-01

    INTRODUCTION History of Software EngineeringSoftware PropertiesOrigins of SoftwareBirth of Software EngineeringThird Paradigm: Iterative ApproachSoftware Life Span ModelsStaged ModelVariants of Staged ModelSoftware Technologies Programming Languages and CompilersObject-Oriented TechnologyVersion Control SystemSoftware ModelsClass DiagramsUML Activity DiagramsClass Dependency Graphs and ContractsSOFTWARE CHANGEIntroduction to Software ChangeCharacteristics of Software ChangePhases of Software ChangeRequirements and Their ElicitationRequirements Analysis and Change InitiationConcepts and Concept

  15. Engineering geology as applied to highway construction

    Science.gov (United States)

    Gard, Leonard M.

    1955-01-01

    A geologic study of the site for a relocated segment of State Highway 93 northwest of Denver Colo., was made by by the Engineering Geology Branch of the U.S. Geological Survey as a demonstration of the applicability of geologic mapping to problems of highway construction. The relocated segment provides access to the Rocky Flats plant of the Atomic Energy Commission.  

  16. ORNL engineering design and construction reengineering report

    Energy Technology Data Exchange (ETDEWEB)

    McNeese, L.E.

    1998-01-01

    A team composed of individuals representing research and development (R and D) divisions, infrastructure support organizations, and Department of Energy (DOE)-Oak Ridge Operations was chartered to reengineer the engineering, design, and construction (ED and C) process at Oak Ridge National Laboratory (ORNL). The team recognized that ED and C needs of both R and D customers and the ORNL infrastructure program have to be met to maintain a viable and competitive national laboratory. Their goal was to identify and recommend implementable best-in-class ED and C processes that will efficiently and cost-effectively support the ORNL R and D staff by being responsive to their programmatic and infrastructure needs. The team conducted process mapping of current and potential ED and C approaches, developed idealized versions of ED and C processes, and identified potential barriers to an efficient ED and C process. Eight subteams were assigned to gather information and to evaluate the significance of potential barriers through benchmarking, surveys, interviews, and reviews of key topical areas in order to determine whether the perceived barriers were real and important and whether they resulted from laws or regulations over which ORNL has no control.

  17. Microbiome engineering: Current applications and its future.

    Science.gov (United States)

    Foo, Jee Loon; Ling, Hua; Lee, Yung Seng; Chang, Matthew Wook

    2017-03-01

    Microbiomes exist in all ecosystems and are composed of diverse microbial communities. Perturbation to microbiomes brings about undesirable phenotypes in the hosts, resulting in diseases and disorders, and disturbs the balance of the associated ecosystems. Engineering of microbiomes can be used to modify structures of the microbiota and restore ecological balance. Consequently, microbiome engineering has been employed for improving human health and agricultural productivity. The importance and current applications of microbiome engineering, particularly in humans, animals, plants and soil is reviewed. Furthermore, we explore the challenges in engineering microbiome and the future of this field, thus providing perspectives and outlook of microbiome engineering.

  18. Civil Engineering Construction of Underground Works

    CERN Document Server

    Rammer, H

    1999-01-01

    For the first time at CERN, new shafts and caverns will be excavated inside a surface building. The LHC civil engineering construction for the ATLAS experiment has been designed such that the experimental hall will be completed to the extent that it can provide a secure, weatherproof and sound insulated covering to the shaft excavation area. The construction of the two access shafts and the experimental cavern will follow and will be carried out inside the building. This unconventional method of working allows the excavation of the Molasse rock in the dry, which is essential for this type of rock, and ensures reduced environmental pollution by noise and dust. The paper will present the technical infrastructure required for this particular construction method, explain its advantages and disadvantages, and compare it with a conventional method of underground excavations to be used on the same work site for the construction of the service cavern.

  19. MR elastography monitoring of tissue-engineered constructs.

    Science.gov (United States)

    Othman, Shadi F; Curtis, Evan T; Plautz, Sarah A; Pannier, Angela K; Butler, Stephanie D; Xu, Huihui

    2012-03-01

    The objective of tissue engineering (TE) is to create functional replacements for various tissues; the mechanical properties of these engineered constructs are critical to their function. Several techniques have been developed for the measurement of the mechanical properties of tissues and organs; however, current methods are destructive. The field of TE will benefit immensely if biomechanical models developed by these techniques could be combined with existing imaging modalities to enable noninvasive, dynamic assessment of mechanical properties during tissue growth. Specifically, MR elastography (MRE), which is based on the synchronization of a mechanical actuator with a phase contrast imaging pulse sequence, has the capacity to measure tissue strain generated by sonic cyclic displacement. The captured displacement is presented in shear wave images from which the complex shear moduli can be extracted or simplified by a direct measure, termed the shear stiffness. MRE has been extended to the microscopic scale, combining clinical MRE with high-field magnets, stronger magnetic field gradients and smaller, more sensitive, radiofrequency coils, enabling the interrogation of smaller samples, such as tissue-engineered constructs. The following topics are presented in this article: (i) current mechanical measurement techniques and their limitations in TE; (ii) a description of the MRE system, MRE theory and how it can be applied for the measurement of mechanical properties of tissue-engineered constructs; (iii) a summary of in vitro MRE work for the monitoring of osteogenic and adipogenic tissues originating from human adult mesenchymal stem cells (MSCs); (iv) preliminary in vivo studies of MRE of tissues originating from mouse MSCs implanted subcutaneously in immunodeficient mice with an emphasis on in vivo MRE challenges; (v) future directions to resolve current issues with in vivo MRE in the context of how to improve the future role of MRE in TE.

  20. Surface Engineering Construction of Sichuan Natural Gas Industry

    Institute of Scientific and Technical Information of China (English)

    You Kaicheng

    1995-01-01

    @@ The Present Status of Surface Engineering Construction A comparatively integrate and systematic surface engineering system, including gas gathering, purification transportation and distribution facilities, which approaches the international technical level, has been established. (Fig. 1)

  1. Current Status of Tissue Engineering Heart Valve.

    Science.gov (United States)

    Shinoka, Toshiharu; Miyachi, Hideki

    2016-11-01

    The development of surgically implantable heart valve prostheses has contributed to improved outcomes in patients with cardiovascular disease. However, there are drawbacks, such as risk of infection and lack of growth potential. Tissue-engineered heart valve (TEHV) holds great promise to address these drawbacks as the ideal TEHV is easily implanted, biocompatible, non-thrombogenic, durable, degradable, and ultimately remodels into native-like tissue. In general, three main components used in creating a tissue-engineered construct are (1) a scaffold material, (2) a cell type for seeding the scaffold, and (3) a subsequent remodeling process driven by cell accumulation and proliferation, and/or biochemical and mechanical signaling. Despite rapid progress in the field over the past decade, TEHVs have not been translated into clinical applications successfully. To successfully utilize TEHVs clinically, further elucidation of the mechanisms for TEHV remodeling and further translational research outcome evaluations will be required. Tissue engineering is a major breakthrough in cardiovascular medicine that holds amazing promise for the future of reconstructive surgical procedures. In this article, we review the history of regenerative medicine, advances in the field, and state-of-the-art in valvular tissue engineering. © The Author(s) 2016.

  2. Construction of Tissue Engineering Artificial Cornea with Skin Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Yuan LIU; Yan JIN

    2005-01-01

    @@ 1 Introduction The clinical need for an alternative to donor corneal tissue has encouraged much interests in recent years. An artificial cornea must fulfill the functions of the cornea it replaces. More recently, the idea of a bio-engineered cornea has risen. Corneal equivalents have been reconstructed by tissue engineering method. Aim of this study is to construct an artificial rabbit cornea by employing tissue engineering method and to determine if skin stem cells have a role in tissue engineered cornea construction.

  3. The construction industry is crying for a new engineer

    OpenAIRE

    Westerström, Göran

    2007-01-01

    There is a great demand for a new engineer within the Swedish Construction Industry, one with a good command of the industrial and construction process as well as the forming and architectonic part of construction. Traditionally, these competencies have developed within different academic disciplines that are rather remote from each other, creating a gap in the increasingly technology driven construction industry of today. To meet this demand in society and industry, a new engineering program...

  4. Detonation Jet Engine. Part 2--Construction Features

    Science.gov (United States)

    Bulat, Pavel V.; Volkov, Konstantin N.

    2016-01-01

    We present the most relevant works on jet engine design that utilize thermodynamic cycle of detonative combustion. Detonation engines of various concepts, pulse detonation, rotational and engine with stationary detonation wave, are reviewed. Main trends in detonation engine development are discussed. The most important works that carried out…

  5. Identification & Control of Special Processes in Civil Engineering Construction

    Institute of Scientific and Technical Information of China (English)

    张怡

    2009-01-01

    @@ A lot ot special processes exist in operation of construction enterprises. Construction enterprises are categorized as of high risks in certification under the quality management system. Taking civil engineering construction of building projects as an example, the writer analyzes how construction enterprises shall identify and control the special processes.

  6. Current state of biomedical engineering; Biomedical Engineering ha ima

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, K. [Waseda Univ., Tokyo (Japan). School of Science and Engineering; Kanamori, T. [National Inst. of Materials and Chemical Research, Tsukuba (Japan)

    1996-11-05

    Medical science is divided into basic medical science and clinical medicine, and the technology of the medical treatment is established as their aggregate power. This concept can be compared with the presence of industrial engineering as a product of physical science and engineering. Basic medical science has come to be combined with science deeply as a result of the rise of recent molecular biology. As to clinical medicine, current highly advanced medical treatment can be said to be made up of scientific technology. Medical treatment can be considered to include prevention, diagnosis, remedy, and rehabilitation stages. It is closely connected with engineering in each stage. The methods of approaching medical science are elucidation of the functions of internal organs and tissue considering that a living body is a plant, and offering of new therapeutical means by applying chemical devices to a living body. The functions of artificial organs can e divided roughly into convection transport, mass transfer, structural members, and signal transfer from the viewpoint of chemical engineering. Medical treatment will be brought into close relation with scientific technology in the future. 10 refs., 3 figs., 2 tabs.

  7. Bacteria engineered for fuel ethanol production: current status

    Energy Technology Data Exchange (ETDEWEB)

    Dien, B.S.; Cotta, M.A. [National Center for Agricultural Utilization Research, Agricultural Research Service, USDA, Peoria, IL (United States); Jeffries, T.W. [Inst. for Microbial and Biochemical Technology, Forest Service, Forest Products Lab., USDA, Madison, WI (United States)

    2004-07-01

    The lack of industrially suitable microorganisms for converting biomass into fuel ethanol has traditionally been cited as a major technical roadblock to developing a bioethanol industry. In the last two decades, numerous microorganisms have been engineered to selectively produce ethanol. Lignocellulosic biomass contains complex carbohydrates that necessitate utilizing microorganisms capable of fermenting sugars not fermentable by brewers' yeast. The most significant of these is xylose. The greatest successes have been in the engineering of gram-negative bacteria: Escherichia coli, Klebsiella oxytoca, and Zymomonas mobilis. E. coli and K. oxytoca are naturally able to use a wide spectrum of sugars, and work has concentrated on engineering these strains to selectively produce ethanol. Z. mobilis produces ethanol at high yields, but ferments only glucose and fructose. Work on this organism has concentrated on introducing pathways for the fermentation of arabinose and xylose. The history of constructing these strains and current progress in refining them are detailed in this review. (orig.)

  8. Reverse engineering: algebraic boundary representations to constructive solid geometry.

    Energy Technology Data Exchange (ETDEWEB)

    Buchele, S. F.; Ellingson, W. A.

    1997-12-17

    Recent advances in reverse engineering have focused on recovering a boundary representation (b-rep) of an object, often for integration with rapid prototyping. This boundary representation may be a 3-D point cloud, a triangulation of points, or piecewise algebraic or parametric surfaces. This paper presents work in progress to develop an algorithm to extend the current state of the art in reverse engineering of mechanical parts. This algorithm will take algebraic surface representations as input and will produce a constructive solid geometry (CSG) description that uses solid primitives such as rectangular block, pyramid, sphere, cylinder, and cone. The proposed algorithm will automatically generate a CSG solid model of a part given its algebraic b-rep, thus allowing direct input into a CAD system and subsequent CSG model generation.

  9. Construction and engineering of large biochemical pathways via DNA assembler.

    Science.gov (United States)

    Shao, Zengyi; Zhao, Huimin

    2013-01-01

    DNA assembler enables rapid construction and engineering of biochemical pathways in a one-step fashion by exploitation of the in vivo homologous recombination mechanism in Saccharomyces cerevisiae. It has many applications in pathway engineering, metabolic engineering, combinatorial biology, and synthetic biology. Here we use two examples including the zeaxanthin biosynthetic pathway and the aureothin biosynthetic gene cluster to describe the key steps in the construction of pathways containing multiple genes using the DNA assembler approach. Methods for construct design, pathway assembly, pathway confirmation, and functional analysis are shown. The protocol for fine genetic modifications such as site-directed mutagenesis for engineering the aureothin gene cluster is also illustrated.

  10. A Study on the Engineering Construction Schedule Control

    Institute of Scientific and Technical Information of China (English)

    Song Shihai

    2014-01-01

    In the whole process of engineering construction,its schedule control is a very important part,which not only directly affects the quality of the whole project,but also plays a very important role in the economic effect of the entire project. Meanwhile,in the particular process of engineering construction,since construction is a dynamic process,coupled with the numerous factors that involved in the engineering construction schedule control and the program is quite complex,it is so imperative to put the factors and program involved in order;and from a dynamic point of view,the construction schedule control can be studied and analyzed in a comprehensive way. The paper begins with the study of relative definitions of engineering construction schedule control and illustrates the involved factors and the corresponding influence of them on the engineering construction schedule control based on the case study of real estate project construction schedule control at Fuyuan Jiayuan of Tai'an City. And some related suggestions are put forward on the base and the author expects to make an active theoretical guidance effect on engineering construction.

  11. Development of multilayer constructs for tissue engineering

    NARCIS (Netherlands)

    Bettahalli, N. M. S.; Groen, N.; Steg, H.; Unadkat, H.; de Boer, J.; van Blitterswijk, C. A.; Wessling, M.; Stamatialis, D.

    2014-01-01

    The rapidly developing field of tissue engineering produces living substitutes that restore, maintain or improve the function of tissues or organs. In contrast to standard therapies, the engineered products become integrated within the patient, affording a potentially permanent and specific cure of

  12. Constructal Theory Of Design In Engineering And Nature

    Directory of Open Access Journals (Sweden)

    Adrian Bejan

    2005-02-01

    Full Text Available This is a brief introduction to an engineering theory on the origin and generation of geometric form in all flow systems: the animate, the inanimate and the engineered. The theory is named constructal, and is based on the thought that it is natural for currents to construct for themselves in time paths of greater flow access. It is shown that this process of flow path optimization can be reasoned on the basis of principle: the maximization of global performance subject to finite-size constraints. One example is the generation of tree-shaped flow patterns, as paths of least resistance between one point (source, sink and an infinity of points (area, volume, as in the circulatory, respiratory and nervous systems. An other is the generation of regular spacings in heat generating volumes, such as swarms of honeybees. The optimized tree-flow geometries account for allometric laws, e. g., the relationship between the total tube contact area and the body size, the proportionality between metabolic rate and body size raised to the power 3/4, the proportionality between breathing and heartbeating times and body size raised to the power 1/4, and the proportionality between the cruising speed of flying bodies (insects, birds, airplanes and body mass raised to the power 1/6. The optimized flow structures constitute robust designs, and robustness improves as the complexity of the system increases. Flow architectures that are more efficient look more natural.

  13. Current Status of the KSTAR Engineering

    Institute of Scientific and Technical Information of China (English)

    J. S. Bak; K. Kim; C. H. Choi; Y. K. Oh; B. C. Kim; N. I. Her; H. L. Yang; G. S. Lee; the KSTAR Team

    2004-01-01

    As there is substantial progress in the KSTAR tokamak engineering, all the major structures and sub-systems are under fabrication and in procurement phase. The vacuum vessel,port, cryostat cylinder, lid, and bellows are being rigorously fabricated in the factory. The lower part of the KSTAR such as cryostat base and gravity support has been almost finished in its fabrication. There are also great progresses and significant results in manufacturing of the superconducting magnet, including four Toroidal Field (TF) coils, lower and upper PF7 coils which are the largest Poloidal Field (PF) coils. The TF00 coil, which has been made for test and back-up of the TF magnet system, was successfully tested in the cool-down and current charging. As the fabrications and procurements of major structures have been actively proceeded, assembly works were also launched from Aug. 2003. More detailed description on these status, results, and plans will be described in this paper.

  14. Digital fabrication in architecture, engineering and construction

    CERN Document Server

    Caneparo, Luca

    2014-01-01

    Digital technologies are changing the relationship between design and construction: with computer models, CAD/CAM, and prototyping, designers can gain direct control of building and construction processes. The ability to digitally model designs, and thus to use those models directly in the context of production, creates a synthesis between design and construction in keeping with the tradition of the close relationship between design and craftsmanship, between the quality of the design and the rules of the craft. The evolution of the culture of design and construction is the underlying theme of this book. The aim is to discuss the direction that innovation is now taking, with a particular focus on today’s cutting-edge architectures. The method addresses the ways in which different societies have dealt with the issues of their age regarding design and construction, the different contributions provided by various techniques, and with them the meanings expressed by the architecture. As building design using dig...

  15. Current Application of Search Engines and Their Developing Trend

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; SHAO Shi-huang; WU Xiao-qiong; ZENG Xian-hui; FAN Xiao-wen

    2002-01-01

    The basic types of current search engines which can help users to perfume laborious information-gathering tasks on Internet is proposed. Basically, the search engines can be classified into index engine, directory engine and agent engine on WWW information service. The key technologies of web mine, automatic classifying of documents and ordering regulation of feedback information are discussed. Finally, the developing trend of search engines is pointed out by analyzing their practical application on World Wide Web.

  16. Challenges in engineering large customized bone constructs.

    Science.gov (United States)

    Forrestal, David P; Klein, Travis J; Woodruff, Maria A

    2017-06-01

    The ability to treat large tissue defects with customized, patient-specific scaffolds is one of the most exciting applications in the tissue engineering field. While an increasing number of modestly sized tissue engineering solutions are making the transition to clinical use, successfully scaling up to large scaffolds with customized geometry is proving to be a considerable challenge. Managing often conflicting requirements of cell placement, structural integrity, and a hydrodynamic environment supportive of cell culture throughout the entire thickness of the scaffold has driven the continued development of many techniques used in the production, culturing, and characterization of these scaffolds. This review explores a range of technologies and methods relevant to the design and manufacture of large, anatomically accurate tissue-engineered scaffolds with a focus on the interaction of manufactured scaffolds with the dynamic tissue culture fluid environment. Biotechnol. Bioeng. 2017;114: 1129-1139. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. Bi-project management in engineering complex industrial construction projects

    NARCIS (Netherlands)

    Velde, Robert R. van der; Donk, Dirk Pieter van

    2000-01-01

    Engineering large industrial construction projects is usually a complex task with several co-operating actors. This paper investigates such projects, characterised by two main actors: the owner of the installation (the client organisation) responsible for the engineering of the production process,

  18. The Engineering Process in Construction & Design

    Science.gov (United States)

    Stoner, Melissa A.; Stuby, Kristin T.; Szczepanski, Susan

    2013-01-01

    Recent research suggests that high-impact activities in science and math classes promote positive attitudinal shifts in students. By implementing high-impact activities, such as designing a school and a skate park, mathematical thinking can be linked to the engineering design process. This hands-on approach, when possible, to demonstrate or…

  19. Construction Site Environmental Impact in Civil Engineering Education

    Science.gov (United States)

    Teixeira, Jose M. Cardoso

    2005-01-01

    The environmental impact of construction activity has gained increasing importance in the last few years and become a key subject for civil engineering education. A survey of Portuguese higher education institutions shows that concern with this topic is mostly directed at the impact of large construction projects and especially focused on their…

  20. Construction site environmental impact in civil engineering education

    OpenAIRE

    Teixeira, José M. Cardoso

    2005-01-01

    The environmental impact of construction activity has gained increasing importance in the last few years and become a key subject for civil engineering education. A survey of Portuguese higher education institutions shows that concern with this topic is mostly directed at the impact of large construction projects and especially focused on their operational stage. The impact of construction sites of smaller projects in urban areas tends to merit less attention, despite their importance for cit...

  1. GIS-Based Simulation of Engineering Construction Schedule

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jing; ZHONG Denghua; HU Chengshun

    2005-01-01

    For its complexity, engineering construction schedule design is limited by various factors.Simulation-based engineering construction schedule takes critical path method (CPM) network as frame and calls complex cyclic operation network (CYCLONE) simulation model enclosed in advance for its simulation nodes. CYCLONE simulation model takes charge of simulating stochastic duration of activity and efficiency of resources, while CPM model performs project scheduling. This combination avoids the shortcomings of both models. Furthermore, geographic information system (GIS) technique is utilized to visualize the construction processes which are otherwise difficult to be understood by static results described. Application in practical project verifies the feasibility and advantage of the technique.

  2. Optimization and control methods in industrial engineering and construction

    CERN Document Server

    Wang, Xiangyu

    2014-01-01

    This book presents recent advances in optimization and control methods with applications to industrial engineering and construction management. It consists of 15 chapters authored by recognized experts in a variety of fields including control and operation research, industrial engineering, and project management. Topics include numerical methods in unconstrained optimization, robust optimal control problems, set splitting problems, optimum confidence interval analysis, a monitoring networks optimization survey, distributed fault detection, nonferrous industrial optimization approaches, neural networks in traffic flows, economic scheduling of CCHP systems, a project scheduling optimization survey, lean and agile construction project management, practical construction projects in Hong Kong, dynamic project management, production control in PC4P, and target contracts optimization.   The book offers a valuable reference work for scientists, engineers, researchers and practitioners in industrial engineering and c...

  3. Construction of Tissue Engineering Artificial Cornea with Skin Stem Cells

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionThe clinical need for an alternative to donor corneal tissue has encouraged much interests in recent years. An artificial cornea must fulfill the functions of the cornea it replaces. More recently, the idea of a bio-engineered cornea has risen. Corneal equivalents have been reconstructed by tissue engineering method. Aim of this study is to construct an artificial rabbit cornea by employing tissue engineering method and to determine if skin stem cells have a role in tissue engineered cornea co...

  4. Improving Construction Process through Integration and Concurrent Engineering

    Directory of Open Access Journals (Sweden)

    Malik Khalfan

    2012-11-01

    Full Text Available In an increasingly competitive business environment, improvedtime-to-market, reduced production cost, quality of the productand customer involvement are rapidly becoming the key successfactors for any product development process. Consequently, mostorganisations are moving towards the adoption of latest technologyand new management concepts and philosophies such as totalquality management and concurrent engineering (CE to bringimprovement in their product development process. This paperdiscusses the adoption of integrated processes and CE withinthe construction industry to enable construction organisations toimprove their project development process. It also discusses aproposed integrated database model for the construction projects,which should enable the construction process to improve, becomemore effective and more efficient.

  5. Chemical Engineering Education - Current and Future Trends

    DEFF Research Database (Denmark)

    Gani, Rafiqul

    design, investigations, engineering practice and transferable skills) and a set guidelines (core curriculum, teaching and learning, industrial experience, review of the education process and student assessment) to achieve them, with special emphasis to the ability to solve problems. They also propose...... a leading role to define the chemical engineering curriculum. The result has been a set of recommendations for the first (BSc), second (MSc) and third (PhD) cycle chemical engineering education aligned to the Bologna Process. They recommend that students studying towards bachelor and masters qualifications...... a diversity of individual, academic and labour-market needs. Within Europe, two types of higher education in chemical engineering can be found: more research-oriented or more application-oriented first cycle programmes. Both types of studies cover a period of 3-4 academic years and 60 credits per year. After...

  6. Perivascular cells and tissue engineering: Current applications and untapped potential.

    Science.gov (United States)

    Avolio, Elisa; Alvino, Valeria V; Ghorbel, Mohamed T; Campagnolo, Paola

    2017-03-01

    The recent development of tissue engineering provides exciting new perspectives for the replacement of failing organs and the repair of damaged tissues. Perivascular cells, including vascular smooth muscle cells, pericytes and other tissue specific populations residing around blood vessels, have been isolated from many organs and are known to participate to the in situ repair process and angiogenesis. Their potential has been harnessed for cell therapy of numerous pathologies; however, in this Review we will discuss the potential of perivascular cells in the development of tissue engineering solutions for healthcare. We will examine their application in the engineering of vascular grafts, cardiac patches and bone substitutes as well as other tissue engineering applications and we will focus on their extensive use in the vascularization of engineered constructs. Additionally, we will discuss the emerging potential of human pericytes for the development of efficient, vascularized and non-immunogenic engineered constructs. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Design and construction of a Stirling engine prototype

    Energy Technology Data Exchange (ETDEWEB)

    Scollo, Leonardo; Valdez, Pablo; Baron, Jorge [CEDIAC Institute, Engineering Faculty, National University of Cuyo, Centro Universitario, Parque Gral. San Martin, CC 405, 5500, Mendoza (Argentina)

    2008-07-15

    In this work an external combustion engine is presented, which was designed through principles of energetic similarity and scaling, combined with adiabatic simulation, pressure loss and heat exchange characteristics analysis. These type of engines have the great advantage of having the heat source applied from outside, therefore resulting in very versatile machines which can be utilized with hydrogen, concentrated solar energy, biomass or fossil fuels. Details of the construction carried out mostly with conventional machine parts produced in Argentina are given. Finally, the results of the preliminary tests with the constructed prototype are shown. (author)

  8. Materials for construction and civil engineering science, processing, and design

    CERN Document Server

    Margarido, Fernanda

    2015-01-01

    This expansive volume presents the essential topics related to construction materials composition and their practical application in structures and civil installations. The book's diverse slate of expert authors assemble invaluable case examples and performance data on the most important groups of materials used in construction, highlighting aspects such as nomenclature, the properties, the manufacturing processes, the selection criteria, the products/applications, the life cycle and recyclability, and the normalization. Civil Engineering Materials: Science, Processing, and Design is ideal for practicing architects; civil, construction, and structural engineers, and serves as a comprehensive reference for students of these disciplines. This book also: ·       Provides a substantial and detailed overview of traditional materials used in structures and civil infrastructure ·       Discusses properties of natural and synthetic materials in construction and materials' manufacturing processes ·  �...

  9. Value engineering awareness study for sustainable construction in Malaysia

    Science.gov (United States)

    U, Fathoni; M, Zakaria C.; O, Rohayu C.

    2013-06-01

    Construction process has often been described as a highly complex process because of the number of disciplines involved during the conceptual, design and construction stage. With the emergence of latest technology and concern for environment, increasing attention in construction industry is given on sustainability. Balance in quality and sustainability has become a major challenge to the construction industry. This paper presents a study that has conducted to determine the acceptance and application of Value Engineering (VE) and Life Cycle Cost Analysis (LCCA) in Malaysia construction industry. A set of questionnaire have distributed to different practitioners in construction industry and the result has reflect the fact that the application of VE and LCCA are still very low.

  10. 77 FR 3070 - Electric Engineering, Architectural Services, Design Policies and Construction Standards

    Science.gov (United States)

    2012-01-23

    ... and 1726 RIN 0572-AC20 Electric Engineering, Architectural Services, Design Policies and Construction...--ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND DESIGN POLICIES AND PROCEDURES 0 1. The authority citation... construction, procurement, engineering services and architectural services for transactions above the...

  11. Evolutionary algorithms and metaheuristics in civil engineering and Construction management

    CERN Document Server

    Greiner, David

    2015-01-01

    This book focuses on civil and structural engineering and construction management applications. The contributions constitute modified, extended and improved versions of research presented at the  minisymposium organized by the editors at the ECCOMAS conference on this topic in Barcelona 2014.

  12. Current Issues of Engineering Education under Globalized Society

    Science.gov (United States)

    Kim, Kwang Sun

    A global world has recently expedited the international collaboration and network among engineering education societies including their scholars. The current issues of engineering education societies have been raised and discussed and those are various topics such as accreditation issues, current trends in engineering and technology education, government policies, innovations, program and project based learning, social sciences in engineering and technology education, university-industry joint programs, human resource development and engineering education, university linkage with K-12, role of engineering education in sustainable development, and the others. Among the variety of issues and topics, the hottest topic is relating to “innovations” of engineering education system. The innovative direction of engineering education in Korea has been reported along with that of USA, whose role has been one of major parts in innovation for the global engineering education system. The recent survey by IFEES (International Federation of Engineering Education Societies) has also been analyzed to consider the current three biggest challenges of global engineering education societies.

  13. Current situation and countermeasures of port logistics park information construction

    Directory of Open Access Journals (Sweden)

    Zhen Liu

    2013-03-01

    Full Text Available Purpose: Improve work efficiency of logistics park department, and drive the economy of the park and its surrounding areas. Design/methodology/approach: Analyze the information development situation and existent questions of current national logistics park, and design proper scheme to meet the demand of port logistics park. Findings: Proposed an information construction implementation plan using technology of the Internet of things which can be applied to port logistics park. Designed a scheme for the park information construction and explained the system's implementation strategy and implementation steps. Practical implications: The proposed construction program is particularly suitable for the northwest port logistics parks in China, and also has reference function to other logistics park construction. Originality/value: Group the information construction of the logistics park into four levels, three types of users, and two requirements. The scheme is innovative and comprehensive, which can ensure the development of port logistics park.

  14. CONSIDERATION REGARDING CURRENT ASSETS IN THE CONSTRUCTION ENTITIES

    Directory of Open Access Journals (Sweden)

    Laura Adriana COJOCARU (ALIONESCU

    2014-06-01

    Full Text Available Accounting for current assets mainly aims to obtain useful information on the management of their best in order to make management decisions. Counting efficiency of these assets, their importance, provides improved performance of the entity. In this paper we want to study the degree of implementation of policies and accounting treatments on the current assets in the specific construction economic entities, the problems of implementation and thus better addressing their theoretical and procedural to improve the information provided by financial statements. Due to the importance of proper conduct of business owned entities, accounting current assets should result in optimal and efficient control of current assets.

  15. CONSIDERATION REGARDING CURRENT ASSETS IN THE CONSTRUCTION ENTITIES

    Directory of Open Access Journals (Sweden)

    Laura Adriana COJOCARU (ALIONESCU

    2014-06-01

    Full Text Available Accounting for current assets mainly aims to obtain useful information on the management of their best in order to make management decisions. Counting efficiency of these assets, their importance, provides improved performance of the entity. In this paper we want to study the degree of implementation of policies and accounting treatments on the current assets in the specific construction economic entities, the problems of implementation and thus better addressing their theoretical and procedural to improve the information provided by financial statements. Due to the importance of proper conduct of business owned entities, accounting current assets should result in optimal and efficient control of current assets.

  16. Mandibular reconstruction using an axially vascularized tissue-engineered construct

    Directory of Open Access Journals (Sweden)

    Khalil Mohamed R

    2011-03-01

    Full Text Available Abstract Background Current reconstructive techniques for continuity defects of the mandible include the use of free flaps, bone grafts, and alloplastic materials. New methods of regenerative medicine designed to restore tissues depend mainly on the so-called extrinsic neovascularization, where the neovascular bed originates from the periphery of the construct. This method is not applicable for large defects in irradiated fields. Methods We are introducing a new animal model for mandibular reconstruction using intrinsic axial vascularization by the Arterio-Venous (AV loop. In order to test this model, we made cadaveric, mechanical loading, and surgical pilot studies on adult male goats. The cadaveric study aimed at defining the best vascular axis to be used in creating the AV loop in the mandibular region. Mechanical loading studies (3 points bending test were done to ensure that the mechanical properties of the mandible were significantly affected by the designed defect, and to put a base line for further mechanical testing after bone regeneration. A pilot surgical study was done to ensure smooth operative and post operative procedures. Results The best vascular axis to reconstruct defects in the posterior half of the mandible is the facial artery (average length 32.5 ± 1.9 mm, caliber 2.5 mm, and facial vein (average length 33.3 ± 1.8 mm, caliber 2.6 mm. Defects in the anterior half require an additional venous graft. The defect was shown to be significantly affecting the mechanical properties of the mandible (P value 0.0204. The animal was able to feed on soft diet from the 3rd postoperative day and returned to normal diet within a week. The mandible did not break during the period of follow up (2 months. Conclusions Our model introduces the concept of axial vascularization of mandibular constructs. This model can be used to assess bone regeneration for large bony defects in irradiated fields. This is the first study to introduce the

  17. Twistor-Inspired Construction of Electroweak Vector Boson Currents

    CERN Document Server

    Bern, Z; Kosower, D A; Mastrolia, Pierpaolo; Bern, Zvi; Forde, Darren; Kosower, David A.; Mastrolia, Pierpaolo

    2004-01-01

    We present an extension of the twistor-motivated MHV vertices and accompanying rules presented by Cachazo, Svrvcek and Witten to the construction of vector-boson currents coupling to an arbitrary source. In particular, we give rules for constructing off-shell vector-boson currents with one fermion pair and n gluons of arbitrary helicity. These currents may be employed directly in the computation of electroweak amplitudes. The rules yield expressions in agreement with previously-obtained results for Z,W,\\gamma^* --> qbar q + n gluons (analytically up to n=3, beyond via the Berends--Giele recursion relations). We also confirm that the contribution to a seven-point amplitude containing the non-abelian triple vector-boson coupling obtained using the next-to-MHV currents matches the previous result in the literature.

  18. Lactose crystallization: current issues and promising Engineering solutions

    OpenAIRE

    Rjabova, A.; Kirsanov, V.; Strizhko, M.; Bredikhin, A.; Semipyatnyi, V.; Chervetsov, V.; Galstyan, A.

    2013-01-01

    Current technological aspects of lactose crystallization are considered. A promising lactose crystallization method involving simulation seed crystals is reported. Advanced engineering solutions for continuous crystallization using spraying in vacuo and scraped-surface heat exchangers are presented.

  19. Quantum current operators; 3, Commutative quantum current operators semi-infinite construction and functional models

    CERN Document Server

    Ding, J; Ding, Jintai; Feigin, Boris

    1996-01-01

    We construct a commutative current operator $\\bar x^+(z)$ inside $U_q(\\hat{\\frak sl}(2))$. With this operator and the condition of quantum integrability on the quantum current of $U_q(\\hat{\\frak sl}(2))$, we derive the quantization of the semi-infinite construction of integrable modules of The quantization of the functional models for $\\hat{\\frak sl}(2)$ are also given.

  20. Engineering photorespiration: current state and future possibilities.

    Science.gov (United States)

    Peterhansel, C; Krause, K; Braun, H-P; Espie, G S; Fernie, A R; Hanson, D T; Keech, O; Maurino, V G; Mielewczik, M; Sage, R F

    2013-07-01

    Reduction of flux through photorespiration has been viewed as a major way to improve crop carbon fixation and yield since the energy-consuming reactions associated with this pathway were discovered. This view has been supported by the biomasses increases observed in model species that expressed artificial bypass reactions to photorespiration. Here, we present an overview about the major current attempts to reduce photorespiratory losses in crop species and provide suggestions for future research priorities.

  1. LHC Civil Engineering Construction Contracts Cost Monitoring and Budget Forecasting

    CERN Document Server

    Skelton, K

    2000-01-01

    The Civil Engineering project for the LHC is estimated at 350 MCHF, of which about 316 MCHF is for the construction contracts. These contracts are based on a system of remeasurement whereby the consultant estimates the quantities required for the construction of each structure and the contractor commits himself to the unit price, which define the initial tender price. There are many factors that affect the final price for these contracts, from increases or decreases in quantities of the estimated amounts in the original bill of quantities to variations to the contract. This paper will look at how these factors change costs at the individual level of a structure to the overall costs of the contract. It will look at how the Civil Engineering Group monitors these changes to calculate cash flows and final costs and how this information is used as a basis for budget forecasts.

  2. Applications of Tissue Engineering in Joint Arthroplasty: Current Concepts Update.

    Science.gov (United States)

    Zeineddine, Hussein A; Frush, Todd J; Saleh, Zeina M; El-Othmani, Mouhanad M; Saleh, Khaled J

    2017-07-01

    Research in tissue engineering has undoubtedly achieved significant milestones in recent years. Although it is being applied in several disciplines, tissue engineering's application is particularly advanced in orthopedic surgery and in degenerative joint diseases. The literature is full of remarkable findings and trials using tissue engineering in articular cartilage disease. With the vast and expanding knowledge, and with the variety of techniques available at hand, the authors aimed to review the current concepts and advances in the use of cell sources in articular cartilage tissue engineering. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Construction informatics - Issues in engineering, computer science and ontology

    DEFF Research Database (Denmark)

    Eir, Asger

    2004-01-01

    . With origin in civil engineering and design issues, the study was directed towards computer science oriented theories in an attempt to introduce such theories in modelling and clarification of the domain. This strategy turned out to be a strength for the study and this thesis. However, it also discovered some...... problems in carrying out such a truly interdisciplinary Ph.D. study. Per Galle s and Dines Bjørner's common background in computer science has been essential for the success of this study. The original title of the Ph.D. project was Design and application of a civil engineering ontology. However, it became....... The issues of the thesis are treated from three angles: from computer science, from civil engineering and design theory, and from philosophy. It is characteristic for the thesis that these angles are all present in analysis and argumentation. The philosophical aspect is a natural ingredient as construction...

  4. Construction informatics - Issues in engineering, computer science and ontology

    DEFF Research Database (Denmark)

    Eir, Asger

    2004-01-01

    . With origin in civil engineering and design issues, the study was directed towards computer science oriented theories in an attempt to introduce such theories in modelling and clarification of the domain. This strategy turned out to be a strength for the study and this thesis. However, it also discovered some...... problems in carrying out such a truly interdisciplinary Ph.D. study. Per Galle s and Dines Bjørner's common background in computer science has been essential for the success of this study. The original title of the Ph.D. project was Design and application of a civil engineering ontology. However, it became....... The issues of the thesis are treated from three angles: from computer science, from civil engineering and design theory, and from philosophy. It is characteristic for the thesis that these angles are all present in analysis and argumentation. The philosophical aspect is a natural ingredient as construction...

  5. Tunnel Engineering Construction Schedule Analysis and Management Based on Visual Simulation

    Institute of Scientific and Technical Information of China (English)

    SONG Yang; ZHONG Wei

    2007-01-01

    The methodology of visual simulation for a tunnel engineering construction schedule is presented. Visualization of simulation model, calculation and result of construction schedule simulation is realized, and the construction simulation and the resource optimization of tunnel engineering are made. A risk analysis and a decision-making method of tunnel engineering construction schedule based on visual simulation are presented. Furthermore, using S curve theory and schedule management method, the real-time management and control method of tunnel engineering construction based on visual simulation is presented. The application to the tunnel engineering construction schedule analysis and management shows the feasibility and effectiveness of the method presented in this paper.

  6. Additive manufacturing techniques for the production of tissue engineering constructs.

    Science.gov (United States)

    Mota, Carlos; Puppi, Dario; Chiellini, Federica; Chiellini, Emo

    2015-03-01

    'Additive manufacturing' (AM) refers to a class of manufacturing processes based on the building of a solid object from three-dimensional (3D) model data by joining materials, usually layer upon layer. Among the vast array of techniques developed for the production of tissue-engineering (TE) scaffolds, AM techniques are gaining great interest for their suitability in achieving complex shapes and microstructures with a high degree of automation, good accuracy and reproducibility. In addition, the possibility of rapidly producing tissue-engineered constructs meeting patient's specific requirements, in terms of tissue defect size and geometry as well as autologous biological features, makes them a powerful way of enhancing clinical routine procedures. This paper gives an extensive overview of different AM techniques classes (i.e. stereolithography, selective laser sintering, 3D printing, melt-extrusion-based techniques, solution/slurry extrusion-based techniques, and tissue and organ printing) employed for the development of tissue-engineered constructs made of different materials (i.e. polymeric, ceramic and composite, alone or in combination with bioactive agents), by highlighting their principles and technological solutions. Copyright © 2012 John Wiley & Sons, Ltd.

  7. 48 CFR 1536.209 - Construction contracts with architect-engineer firms.

    Science.gov (United States)

    2010-10-01

    ... architect-engineer firms. 1536.209 Section 1536.209 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 1536.209 Construction contracts with architect-engineer firms....

  8. 76 FR 58155 - Defense Federal Acquisition Regulation Supplement; Construction and Architect-Engineer Services...

    Science.gov (United States)

    2011-09-20

    ... Regulation Supplement; Construction and Architect-Engineer Services Performance Evaluation (DFARS Case 2010... construction and architect-engineer services. DATES: Effective Date: September 20, 2011. FOR FURTHER... construction and Architect- Engineer services. On April 19, 2011, DoD published a proposed rule in the...

  9. 48 CFR 2936.209 - Construction contracts with architect-engineer firms.

    Science.gov (United States)

    2010-10-01

    ... with architect-engineer firms. 2936.209 Section 2936.209 Federal Acquisition Regulations System DEPARTMENT OF LABOR GENERAL CONTRACTING REQUIREMENTS CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 2936.209 Construction contracts with architect-engineer firms....

  10. 48 CFR 36.209 - Construction contracts with architect-engineer firms.

    Science.gov (United States)

    2010-10-01

    ... with architect-engineer firms. 36.209 Section 36.209 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 36.209 Construction contracts with architect-engineer firms....

  11. 48 CFR 636.209 - Construction contracts with architect-engineer firms.

    Science.gov (United States)

    2010-10-01

    ... with architect-engineer firms. 636.209 Section 636.209 Federal Acquisition Regulations System DEPARTMENT OF STATE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 636.209 Construction contracts with architect-engineer firms....

  12. Current Density Measurements of an Annular-Geometry Ion Engine

    Science.gov (United States)

    Shastry, Rohit; Patterson, Michael J.; Herman, Daniel A.; Foster, John E.

    2012-01-01

    The concept of the annular-geometry ion engine, or AGI-Engine, has been shown to have many potential benefits when scaling electric propulsion technologies to higher power. However, the necessary asymmetric location of the discharge cathode away from thruster centerline could potentially lead to non-uniformities in the discharge not present in conventional geometry ion thrusters. In an effort to characterize the degree of this potential nonuniformity, a number of current density measurements were taken on a breadboard AGI-Engine. Fourteen button probes were used to measure the ion current density of the discharge along a perforated electrode that replaced the ion optics during conditions of simulated beam extraction. Three Faraday probes spaced apart in the vertical direction were also used in a separate test to interrogate the plume of the AGI-Engine during true beam extraction. It was determined that both the discharge and the plume of the AGI-Engine are highly uniform, with variations under most conditions limited to 10% of the average current density in the discharge and 5% of the average current density in the plume. Beam flatness parameter measured 30 mm from the ion optics ranged from 0.85 0.95, and overall uniformity was shown to generally increase with increasing discharge and beam currents. These measurements indicate that the plasma is highly uniform despite the asymmetric location of the discharge cathode.

  13. Genetically engineered multivalent single chain antibody constructs for cancer therapy

    Energy Technology Data Exchange (ETDEWEB)

    Surinder Batra, Ph D

    2006-02-27

    its tumor: normal tissue ratio for improved therapeutic index, we engineered a variety antibody constructs. These constructs were evaluated using novel approaches like special radionuclides, pretargeting and optimization. Due to the smaller size, the engineered antibody molecules should penetrate better throughout a tumor mass, with less dose heterogeneity, than is the case with intact IgG. Multivalent scFvs with an appropriate radionuclide, therefore, hold promising prospects for cancer therapy and clinical imaging in MAb-based radiopharmaceuticals. In addition, the human anti-mouse antibodies (HAMA) responses in patients against antibody-based therapy are usually directed against the immunoglobulin constant regions; however, anti-idiotypic responses can also be detected. The HAMA responses reduce the efficacy of treatment by removing the circulating antibody molecules, fragments, and possibly scFvs by altering the pharmacokinetic properties of the antibody. HAMA responses against divalent IgG, divalent Ig fragments, and possibly multimeric scFvs could cause immune complex formation with hypersensitivity or allergic reactions that could be harmful to patients. The use of small molecules, such as scFvs (monomeric as well as multimeric), with their shorter biological half-lives and the lack of the constant regions and humanized variable (binding regions) performed in our studies should reduce the development of HAMA. The generation of humanized and fully human scFvs should further reduce the development of HAMA. Specific accomplishments on the project are the production of large amounts of recombinant antibodies as they are required in large amounts for cancer diagnosis and therapy. A variety of single-chain Fv (scFv) constructs were engineered for the desired pharmacokinetic properties. Tetrameric and dimeric scFvs showed a two-fold advantage: (1) there was a considerable gain in avidity as compared to smaller fragments, and (2) the biological half-life was more

  14. Construction Unit Training Challenges: A Proposal for Construction Engineer Qualification Tables

    Science.gov (United States)

    2010-12-01

    field manuals (FMs) and STPs in a classroom-type en- vironment, where most of the learning is done by reading the FMs and applying the lessons in a...organizations to Fort Stewart, Georgia, to teach its Soldiers. These organizations included AutoCAD ®, EMC Engineering Services Incorporated, the United...diers need to be assigned to the class. For example, the 92d sent its company executive officers and drafters to the AutoCAD class, construction

  15. Facilitating Industrial Placement in the Construction Engineering Curriculum

    DEFF Research Database (Denmark)

    Wandahl, Søren; Ussing, Lene Faber

    2016-01-01

    student learning from construction practice whereby students can reflect on their learning experience at the university. The interplay between traditional engineering curriculum and the context-based learning is important for securing the right skills and competencies among the graduates. This paper takes...... for the program to facilitate the industrial placement effectively. How to do so is investigated through a large survey among student that has finalized an internship scheme. The sample size consists of entries. Guidance on how to facilitate internship most effectively pre, per and post scheme is outlined...

  16. Facilitating Industrial Placement in the Construction Engineering Curriculum

    DEFF Research Database (Denmark)

    Wandahl, Søren; Faber, Lene

    2016-01-01

    student learning from construction practice whereby students can reflect on their learning experience at the university. The interplay between traditional engineering curriculum and the context based learning is important for securing the right skills and competencies among the graduates. This paper takes...... for the program to facilitate the industrial placement effectively. How to do so is investigated through a large survey among student that has finalized an internship scheme. The sample size consists of entries. Guidance on how to facilitate internship most effectively pre, per and post scheme is outlined...

  17. A Continuing Education Short Course and Engineering Curriculum to Accelerate Workforce Development in Wind Power Plant Design, Construction, and Operations

    Energy Technology Data Exchange (ETDEWEB)

    Tinjum, James [Univ. of Wisconsin, Madison, WI (United States)

    2012-11-29

    Significant advances in wind turbine technology and wind turbine power plant capabilities are appearing in the U.S. Sites that only 10 years ago might have been overlooked are being considered for build out. However, the development of a skilled workforce in the engineering fields and construction trades lags the potential market, especially if the industry is expected to site, design, construct, and operate sufficient wind power plant sites to meet the potential for 20% wind energy by 2030. A select few firms have penetrated the engineer-procure-construction (EPC) market of wind power plant construction. Competition and know-how in this market is vital to achieve cost-effective, design-construct solutions. The industry must produce or retrain engineers, contractors, and technicians to meet ambitious goals. Currently, few universities offer undergraduate or graduate classes that teach the basics in designing, building, and maintaining wind power plants that are safe, efficient, and productive.

  18. Current trends in health facility planning, design, and construction.

    Science.gov (United States)

    Beale, Craig; Kittredge, Frank D

    2014-01-01

    It is critical now more than ever for today's healthcare facilities to serve as more than just a backdrop to the care provided--they can, and should, be an integral part of that care. In addition to promoting efficacy, delighting the senses, and placing patients and families at ease, facilities need to be high-performing, sustainable, and healthy environments. Creating today's healthcare facilities requires breaking through barriers in unexpected ways, and it often requires looking outside the healthcare profession for guidance. In this article, we explore current trends in health facility planning, design, and construction. Our focus is on the buildings that serve as venues for the provision of healthcare services across the full continuum, from prevention to critical care. In particular, we discuss four current broad trends and conclude with thoughts on future developments.

  19. Evaluation of Current Assessment Methods in Engineering Entrepreneurship Education

    Science.gov (United States)

    Purzer, Senay; Fila, Nicholas; Nataraja, Kavin

    2016-01-01

    Quality assessment is an essential component of education that allows educators to support student learning and improve educational programs. The purpose of this study is to evaluate the current state of assessment in engineering entrepreneurship education. We identified 52 assessment instruments covered in 29 journal articles and conference…

  20. Current opportunities and challenges in skeletal muscle tissue engineering

    NARCIS (Netherlands)

    Koning, Merel; Harmsen, Martin C; van Luyn, Marja J A; Werker, Paul M N

    The purpose of this article is to give a concise review of the current state of the art in tissue engineering (TE) of skeletal muscle and the opportunities and challenges for future clinical applicability. The endogenous progenitor cells of skeletal muscle, i.e. satellite cells, show a high

  1. Stem Cells and Scaffolds for Vascularizing Engineered Tissue Constructs

    Science.gov (United States)

    Luong, E.; Gerecht, S.

    The clinical impact of tissue engineering depends upon our ability to direct cells to form tissues with characteristic structural and mechanical properties from the molecular level up to organized tissue. Induction and creation of functional vascular networks has been one of the main goals of tissue engineering either in vitro, for the transplantation of prevascularized constructs, or in vivo, for cellular organization within the implantation site. In most cases, tissue engineering attempts to recapitulate certain aspects of normal development in order to stimulate cell differentiation and functional tissue assembly. The induction of tissue growth generally involves the use of biodegradable and bioactive materials designed, ideally, to provide a mechanical, physical, and biochemical template for tissue regeneration. Human embryonic stem cells (hESCs), derived from the inner cell mass of a developing blastocyst, are capable of differentiating into all cell types of the body. Specifically, hESCs have the capability to differentiate and form blood vessels de novo in a process called vasculogenesis. Human ESC-derived endothelial progenitor cells (EPCs) and endothelial cells have substantial potential for microvessel formation, in vitro and in vivo. Human adult EPCs are being isolated to understand the fundamental biology of how these cells are regulated as a population and to explore whether these cells can be differentiated and reimplanted as a cellular therapy in order to arrest or even reverse damaged vasculature. This chapter focuses on advances made toward the generation and engineering of functional vascular tissue, focusing on both the scaffolds - the synthetic and biopolymer materials - and the cell sources - hESCs and hEPCs.

  2. A Review of Engine Seal Performance and Requirements for Current and Future Army Engine Platforms

    Science.gov (United States)

    Delgado, Irebert R.; Proctor, Margaret P.

    2008-01-01

    Sand ingestion continues to impact combat ground and air vehicles in military operations in the Middle East. The T-700 engine used in Apache and Blackhawk helicopters has been subjected to increased overhauls due to sand and dust ingestion during desert operations. Engine component wear includes compressor and turbine blades/vanes resulting in decreased engine power and efficiency. Engine labyrinth seals have also been subjected to sand and dust erosion resulting in tooth tip wear, increased clearances, and loss in efficiency. For the current investigation, a brief overview is given of the history of the T-700 engine development with respect to sand and dust ingestion requirements. The operational condition of labyrinth seals taken out of service from 4 different locations of the T-700 engine during engine overhauls are examined. Collaborative efforts between the Army and NASA to improve turbine engine seal leakage and life capability are currently focused on noncontacting, low leakage, compliant designs. These new concepts should be evaluated for their tolerance to sand laden air. Future R&D efforts to improve seal erosion resistance and operation in desert environments are recommended

  3. 7 CFR 1717.604 - Long-range engineering plans and construction work plans.

    Science.gov (United States)

    2010-01-01

    ... construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and construction work plans (CWPs) in form and substance as set forth in 7 CFR part 1710, subpart F. (b... 7 Agriculture 11 2010-01-01 2010-01-01 false Long-range engineering plans and construction...

  4. 48 CFR 836.209 - Construction contracts with architect-engineer firms.

    Science.gov (United States)

    2010-10-01

    ... with architect-engineer firms. 836.209 Section 836.209 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 836.209 Construction contracts with...

  5. 48 CFR 1436.209 - Construction contracts with architect-engineer firms.

    Science.gov (United States)

    2010-10-01

    ... with architect-engineer firms. 1436.209 Section 1436.209 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 1436.209 Construction contracts with...

  6. 48 CFR 436.209 - Construction contracts with architect-engineer firms.

    Science.gov (United States)

    2010-10-01

    ... with architect-engineer firms. 436.209 Section 436.209 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 436.209 Construction contracts with...

  7. 48 CFR 31.201-7 - Construction and architect-engineer contracts.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Construction and architect... Organizations 31.201-7 Construction and architect-engineer contracts. Specific principles and procedures for... architect-engineer contracts related to construction projects, are in 31.105. The applicability of...

  8. 76 FR 21851 - Defense Federal Acquisition Regulation Supplement; Construction and Architect-Engineer Services...

    Science.gov (United States)

    2011-04-19

    ... Regulation Supplement; Construction and Architect-Engineer Services Performance Evaluation (DFARS Case 2010... construction and architect-engineer services. DATES: Comments on the proposed rule should be submitted in... requirement to use DoD-unique forms to document contractor past performance for construction and...

  9. Wakimoto realizations of current algebras an explicit construction

    CERN Document Server

    De Boer, J; Boer, Jan de; Feher, Laszlo

    1997-01-01

    A generalized Wakimoto realization of $\\widehat{\\cal G}_K$ can be associated with each parabolic subalgebra ${\\cal P}=({\\cal G}_0 +{\\cal G}_+)$ of a simple Lie algebra ${\\cal G}$ according to an earlier proposal by Feigin and Frenkel. In this paper the proposal is made explicit by developing the construction of Wakimoto realizations from a simple but unconventional viewpoint. An explicit formula is derived for the Wakimoto current first at the Poisson bracket level by Hamiltonian symmetry reduction of the WZNW model. The quantization is then performed by normal ordering the classical formula and determining the required quantum correction for it to generate $\\widehat{\\cal G}_K$ by means of commutators. The affine-Sugawara stress-energy tensor is verified to have the expected quadratic form in the constituents, which are symplectic bosons belonging to ${\\cal G}_+$ and a current belonging to ${\\cal G}_0$. The quantization requires a choice of special polynomial coordinates on the big cell of the flag manifold $...

  10. Meteorological Conditions Causing Jet-Engine Poweloss Events: Current Understanding

    Science.gov (United States)

    Strapp, J. W.; Ratvasky, T. P.

    2009-09-01

    The aviation industry is currently investigating a regular occurrence of jet engine-powerloss events which have now been attributed to the ingestion of atmospheric ice particles, usually in the vicinity of deep convection. There is a limited amount of information on the cloud microphysical properties near the cores of deep convection due to the potential hazards of flying in these areas, and due to the fact that it is a very challenging environment for current instrumentation. Most of the information that has been used to deduce the details of the conditions that cause engine powerloss has been extracted from the event-aircraft flight data recorders, pilot interviews, ground radar and satellite, a series of flight test programs in the 1950s and again in the 1990s, and the most recently available limited data from the cloud physics community. These have led to the conclusion that engine events occur due to flight through high mass concentrations of ice particles, probably with ice water contents (IWCs) in excess of 2 grams per cubic meter, and perhaps as high as 8. The limited microphysical data available has been used to suggest a median mass diameter of the ice particles of ~200 microns, with some evidence that it may be as low as 40 microns. These small particle sizes in the presence of high mass concentration is consistent with the lack of radar echoes > 20 dBZ observed on the pilot's radar, a consistent observation during engine events. The Engine Harmonization Working Group, an industry/regulator/government committee investigating engine powerloss, has concluded that the level of understanding of the properties of these clouds is inadequate to provide guidance to industry for engine design and testing. In order to address this issue, NASA and Environment Canada are planning to instrument an aircraft to make measurements in high IWC regions of tropical monsoon and continental convection. There is also a significant effort to upgrade and develop new

  11. Engineering Critical Current Density Improvement in Ag- Bi-2223 Tapes

    DEFF Research Database (Denmark)

    Wang, W. G.; Seifi, Behrouz; Eriksen, Morten;

    2000-01-01

    Ag alloy sheathed Bi-2223 multifilament tapes were produced by the powder-in-tube method. Engineering critical current density improvement has been achieved through both enhancement of critical current density by control of the thermal behavior of oxide powder and by an increase of the filling...... the superconductor composite sustaining large proportional oxide ceramics in the composite during drawing and rolling process. By optimization of the thermal and mechanical process, a Je of 12 kA/cm2 has been achieved in a 0.183.1 mm2 size tape which carried 67 A...

  12. Nanostructured 3D Constructs Based on Chitosan and Chondroitin Sulphate Multilayers for Cartilage Tissue Engineering

    NARCIS (Netherlands)

    Silva, J.M.; Georgi, Nicole; Costa, R.; Sher, P.; Reis, R L; van Blitterswijk, Clemens; Karperien, Hermanus Bernardus Johannes; Mano, J.F.

    2013-01-01

    Nanostructured three-dimensional constructs combining layer-by-layer technology (LbL) and template leaching were processed and evaluated as possible support structures for cartilage tissue engineering. Multilayered constructs were formed by depositing the polyelectrolytes chitosan (CHT) and

  13. A leadership-as-practice perspective on design in architecture, engineering and construction projects: interaction analysis of a collaborative workshop

    NARCIS (Netherlands)

    Zerjav, Vedran; Hartmann, Timo; van Amstel, Frederick

    2014-01-01

    This paper proposes an alternative perspective on the role of leadership in the context of collaborative practices in architecture, engineering and construction design. While most of current leadership literature is focused on outstanding individuals with abilities to influence others, the aim of

  14. Current challenges for education of nuclear engineers. Beyond nuclear basics

    Energy Technology Data Exchange (ETDEWEB)

    Schoenfelder, Christian [AREVA GmbH, Offenbach (Germany). Training Center

    2014-07-15

    In past decades, curricula for the education of nuclear engineers (either as a major or minor subject) have been well established all over the world. However, from the point of view of a nuclear supplier, recent experiences in large and complex new build as well as modernization projects have shown that important competences required in these projects were not addressed during the education of young graduates. Consequently, in the past nuclear industry has been obliged to either accept long periods for job familiarization, or to develop and implement various dedicated internal training measures. Although the topics normally addressed in nuclear engineering education (like neutron and reactor physics, nuclear materials or thermohydraulics and the associated calculation methods) build up important competences, this paper shows that the current status of nuclear applications requires adaptations of educational curricula. As a conclusion, when academic nuclear engineering curricula start taking into account current competence needs in nuclear industry, it will be for the benefit of the current and future generation of nuclear engineers. They will be better prepared for their future job positions and career perspectives, especially on an international level. The recommendations presented should not only be of importance for the nuclear fission field, but also for the fusion community. Here, the Horizon 2020 Roadmap to Fusion as published in 2012 now is focusing on ITER and on a longer-term development of fusion technology for a future demonstration reactor DEMO. The very challenging work program is leading to a strong need for exactly those skills that are described in this article.

  15. A novel bioprinting method and system for forming hybrid tissue engineering constructs.

    Science.gov (United States)

    Shanjani, Y; Pan, C C; Elomaa, L; Yang, Y

    2015-12-18

    Three dimensional (3D) bioprinting is a promising approach to form tissue engineering constructs (TECs) via positioning biomaterials, growth factors, and cells with controlled spatial distribution due to its layer-by-layer manufacturing nature. Hybrid TECs composed of relatively rigid porous scaffolds for structural and mechanical integrity and soft hydrogels for cell- and growth factor-loading have a tremendous potential to tissue regeneration under mechanical loading. However, despite excessive progress in the field, the current 3D bioprinting techniques and systems fall short in integration of such soft and rigid multifunctional components. Here we present a novel 3D hybrid bioprinting technology (Hybprinter) and its capability enabling integration of soft and rigid components for TECs. Hybprinter employs digital light processing-based stereolithography (DLP-SLA) and molten material extrusion techniques for soft and rigid materials, respectively. In this study, poly-ethylene glycol diacrylate (PEGDA) and poly-(ε-caprolactone) (PCL) were used as a model material for soft hydrogel and rigid scaffold, respectively. It was shown that geometrical accuracy, swelling ratio and mechanical properties of the hydrogel component can be tailored by DLP-SLA module. We have demonstrated the printability of variety of complex hybrid construct designs using Hybprinter technology and characterized the mechanical properties and functionality of such constructs. The compressive mechanical stiffness of a hybrid construct (90% hydrogel) was significantly higher than hydrogel itself (∼6 MPa versus 100 kPa). In addition, viability of cells incorporated within the bioprinted hybrid constructs was determined approximately 90%. Furthermore, a functionality of a hybrid construct composed of porous scaffold with an embedded hydrogel conduit was characterized for vascularized tissue engineering applications. High material diffusion and high cell viability in about 2.5 mm distance

  16. Engineered skeletal muscle tissue for soft robotics: fabrication strategies, current applications, and future challenges.

    Science.gov (United States)

    Duffy, Rebecca M; Feinberg, Adam W

    2014-01-01

    Skeletal muscle is a scalable actuator system used throughout nature from the millimeter to meter length scales and over a wide range of frequencies and force regimes. This adaptability has spurred interest in using engineered skeletal muscle to power soft robotics devices and in biotechnology and medical applications. However, the challenges to doing this are similar to those facing the tissue engineering and regenerative medicine fields; specifically, how do we translate our understanding of myogenesis in vivo to the engineering of muscle constructs in vitro to achieve functional integration with devices. To do this researchers are developing a number of ways to engineer the cellular microenvironment to guide skeletal muscle tissue formation. This includes understanding the role of substrate stiffness and the mechanical environment, engineering the spatial organization of biochemical and physical cues to guide muscle alignment, and developing bioreactors for mechanical and electrical conditioning. Examples of engineered skeletal muscle that can potentially be used in soft robotics include 2D cantilever-based skeletal muscle actuators and 3D skeletal muscle tissues engineered using scaffolds or directed self-organization. Integration into devices has led to basic muscle-powered devices such as grippers and pumps as well as more sophisticated muscle-powered soft robots that walk and swim. Looking forward, current, and future challenges include identifying the best source of muscle precursor cells to expand and differentiate into myotubes, replacing cardiomyocytes with skeletal muscle tissue as the bio-actuator of choice for soft robots, and vascularization and innervation to enable control and nourishment of larger muscle tissue constructs.

  17. Engineering controls for selected silica and dust exposures in the construction industry--a review.

    Science.gov (United States)

    Flynn, Michael R; Susi, Pam

    2003-04-01

    This literature review summarizes engineering control technology research for dust and silica exposures associated with selected tasks in the construction industry. Exposure to crystalline silica can cause silicosis and lung fibrosis, and evidence now links it with lung cancer. Of over 30 references identified and reviewed, 16 were particularly significant in providing data and analyses capable of documenting the efficacy of various engineering controls. These reports include information on generation rates and worker exposures to silica and dust during four different tasks: cutting brick and concrete block, grinding mortar from between bricks, drilling, and grinding concrete surfaces. The major controls are wet methods and local exhaust ventilation. The studies suggest that while the methods provide substantial exposure reductions, they may not reduce levels below the current ACGIH threshold limit value (TLV) of 0.05 mg/m(3) for respirable quartz. Although further research on controls for these operations is indicated, it is clear that effective methods exist for significant exposure reduction.

  18. Engineering, Support, and Management Services: Construction Industry Series: Preparation Level: Student Manual and Instructor's Guide.

    Science.gov (United States)

    Texas Education Agency, Austin. Dept. of Occupational Education and Technology.

    The guide is an outline of training experiences designed to lead a student to at least entry-level proficiency in engineering, support, and management service jobs within the construction industry. Teaching units cover construction drafting, architectural drawing, engineering drafting, estimating, expediting and scheduling, surveying, testing and…

  19. 48 CFR 952.236 - Construction and architect-engineer contracts.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Construction and architect-engineer contracts. 952.236 Section 952.236 Federal Acquisition Regulations System DEPARTMENT OF ENERGY... Construction and architect-engineer contracts....

  20. All-in-one construct for genome engineering using Cre-lox technology.

    Science.gov (United States)

    Mariscal, Ana M; González-González, Luis; Querol, Enrique; Piñol, Jaume

    2016-06-01

    Mycoplasma genitalium is an appealing model of a minimal cell and synthetic biology study, and it was one of the first organisms whose genome was fully sequenced and chemically synthesized. Despite its usefulness as a model organism, many genetic tools well established for other microorganisms are not currently available in mycoplasmas. We have developed several vectors to adapt the Cre-lox technology for genome engineering in M. genitalium, providing an all-in-one construct that could be also useful to obtain unmarked genetic modifications in many other slow growing microorganisms. This construct contains a modified promoter sequence based in TetR system that exhibits an enhanced control on Cre recombinase expression, virtually abolishing the presence of this recombinase in the absence of inducer. This allows to introduce the Cre recombinase gene and the desired genetic modification in a single transformation step. In addition, this inducible promoter may be a very promising tool for a wide range of molecular applications.

  1. Construction of an Engineer's Notebook Rubric

    Science.gov (United States)

    Kelley, Todd R.

    2014-01-01

    It is evident that there is a need for assessment instruments that measure design and engineering design skills, knowledge, and ways of design thinking. These student assessments must be authentic to engineering design practices and measure key elements of the engineering design process. Kelley (2011) presented a rationale to include…

  2. Construction of an Engineer's Notebook Rubric

    Science.gov (United States)

    Kelley, Todd R.

    2014-01-01

    It is evident that there is a need for assessment instruments that measure design and engineering design skills, knowledge, and ways of design thinking. These student assessments must be authentic to engineering design practices and measure key elements of the engineering design process. Kelley (2011) presented a rationale to include…

  3. Educational Horsepower: Engine Design and Construction in the Classroom

    Science.gov (United States)

    Christensen, Brad

    2007-01-01

    Engines, in their many forms and functions, have had a tremendous impact on society and the environment. It is hard for the contemporary student to fathom a world without trains, cars, trucks, powerboats, and airplanes. With the fascination, history, impacts, and importance of engines to modern society, it is only natural that engine technology…

  4. Is the current theory of construction a hindrance to innovation?

    NARCIS (Netherlands)

    Koskela, L.; Vrijhoef, R.

    2001-01-01

    An explanation for the low innovation activity in const¡uction is put forward. The central argument is that the cur¡ent theory of construction is one root cause for low innovation activity. Instead, an explicit and more powerful theory of construction is needed for further imovation, which is 'to ma

  5. 7 CFR 1717.606 - Standard forms of construction contracts, and engineering and architectural services contracts.

    Science.gov (United States)

    2010-01-01

    ... engineering and architectural services contracts. 1717.606 Section 1717.606 Agriculture Regulations of the... Standard forms of construction contracts, and engineering and architectural services contracts. All..., materials, equipment, engineering services, and architectural services, regardless of the source of funding...

  6. Human Oral Mucosa Tissue-Engineered Constructs Monitored by Raman Fiber-Optic Probe

    OpenAIRE

    Khmaladze, Alexander; Kuo, Shiuhyang; Kim, Roderick Y; Matthews, Robert V.; Marcelo, Cynthia L.; Feinberg, Stephen E.; Morris, Michael D.

    2014-01-01

    In maxillofacial and oral surgery, there is a need for the development of tissue-engineered constructs. They are used for reconstructions due to trauma, dental implants, congenital defects, or oral cancer. A noninvasive monitoring of the fabrication of tissue-engineered constructs at the production and implantation stages done in real time is extremely important for predicting the success of tissue-engineered grafts. We demonstrated a Raman spectroscopic probe system, its design and applicati...

  7. Conventional alternating-current generators and engine generator sets

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.L.

    1978-04-01

    Available data and techniques relevant to the selection and analysis of appropriate electrical generating equipment for application in the ICES program are presented. Of the general classes of commercially available a-c generators, the synchronous, rotating field alternator is most suited to ICES applications, and the focus of this technology evaluation. Conventional 60-Hz, alternating-current generators, with standard ratings ranging from 1.25 kVA to 10,000 kVA at voltages from 125 single-phase to 14,400 volts three-phase and speeds up to 1800 rpm are covered. Technical data for representative diesel engine-generator sets for continuous prime power ratings up to 6445 kW are presented. Approximate 1976 costs of standard electrical generating equipment are given for: (1) standard conventional alternating current generators and (2) packaged engine-generator sets. The data indicate a decrease in unit costs as the power ratings increase, with the cost of the slow-speed units somewhat greater than that of the higher speed units. Maintenance data for a typical total energy plant presently in operation indicate that the average cost of maintenance amounts to 41 cents/kWh. A plot of available data also indicates a trend to decreasing operating costs with increasing unit size.

  8. On how to do construction management communications engineering

    Institute of Scientific and Technical Information of China (English)

    Zhang Zhi

    2014-01-01

    In the communication construction projects, improving the efectivenes of project management is an important part of the quality asurance program. The efectivenes of the communication and construction project management is afected by many factors. Therefore, the discusion of communication construction project management efectivenes is good for improving the quality of projects of great significance. This paper analyzes the characteristics and problems of communication construction projects, reflecting the importance of project management; then discused the factors afecting the efectivenes of project management; finaly targeted to improve the communication of construction project management efectivenes propose specific methods to ensure communication quality of construction projects.

  9. [Introduction to] : "Sustainability of constructions : integrated approach to life-time structural engineering"

    OpenAIRE

    Bragança, L.; Koukkari, Heli; Blok, Rijk; Gervásio, H.; Veljkovic, Milan, ed. lit.; Plewako, Zbigniew, ed. lit.; Landolfo, Raffaele; Ungureanu, Viorel

    2010-01-01

    The main objective of the COST Action C25 ‘Sustainability of Constructions: Integrated Approach lo Life-time Structural Engineering” is to promote science-based developments in sustainable construction in Europe through the collection and collaborative analysis of scientific results concerning life-time structural engineering and especially integration of environmental assessment methods and tolls of structural engineering. Sustainability of Construction, European Science Foundation : Cost...

  10. Engineering design of a high-temperature superconductor current lead

    Science.gov (United States)

    Niemann, R. C.; Cha, Y. S.; Hull, J. R.; Daugherty, M. A.; Buckles, W. E.

    As part of the US Department of Energy's Superconductivity Pilot Center Program, Argonne National Laboratory and Superconductivity, Inc., are developing high-temperature superconductor (HTS) current leads suitable for application to superconducting magnetic energy storage systems. The principal objective of the development program is to design, construct, and evaluate the performance of HTS current leads suitable for near-term applications. Supporting objectives are to (1) develop performance criteria; (2) develop a detailed design; (3) analyze performance; (4) gain manufacturing experience in the areas of materials and components procurement, fabrication and assembly, quality assurance, and cost; (5) measure performance of critical components and the overall assembly; (6) identify design uncertainties and develop a program for their study; and (7) develop application-acceptance criteria.

  11. The Role of the Military Construction Engineers in the Hybrid War

    Science.gov (United States)

    2015-06-12

    military role in post conflict reconstruction. Williams uses historic examples from Bosnia, Kosovo , and Afghanistan. The author describes the...Provide Waste Management Provide Engineer Support to Bases and Installtions Enable Logistics Construct Roads and Highways Construct Over-the-shore...exists. The construction efforts will not support the strategic endstate, and resources will be wasted . 2 Cooperate with non-military

  12. The current state of computing in building design and construction

    DEFF Research Database (Denmark)

    Sørensen, Lars Schiøtt; Andersen, Tom

    1996-01-01

    An exhaustive IT-survey is made in the Danish construction industry in 1995. The outcome of this survey is outlined for a selected number of issues, such as number and types of CAD-systems, data base systems, networking etc. The survey shows, that the use of IT is massive. A detailed investigation...... in relation to AI-based systems is presented. This indicates that AI-based systems/approaches have not yet penetrated in the Danish construction industry. Determinants relevant to technology penetration are described, and the immediate potential for AI-penetration are discussed and compared with the actual...

  13. An Investigation of Women Engineers in Non-Traditional Occupations in the Thai Construction Industry

    Directory of Open Access Journals (Sweden)

    Nuanthip Kaewsri

    2011-06-01

    Full Text Available For over a decade, the public and the private sectors have carried out research aimed at attracting women engineers to the construction industry and retaining them. However, studies on women engineers working in other types of construction-related businesses apart from contractor companies such as consultancies, developers, etc., have not been many. This paper aims to examine the experiences of women engineers in non-traditional careers and the implications for their turnover. A literature search on women’s careers in construction was performed in conjunction with semi-structured interviews with a sampling of 141 individuals. Results from three viewpoints, viz those of professional men and women engineers in contractor companies, and women engineers in non-contractor companies, were found to differ in many respects, including their opinions about career advancement, career path and the difficulties involved. It was also found that women engineers in contractor companies were much more affected by problems such as sexual harassment, work-life conflicts and equal opportunity than women engineers in non-contractor companies. Turnover rates of women engineers and their reasons for leaving were examined. Women engineers, particularly those in contractor companies, had to confront more barriers in non-traditional careers than their male counterparts.  Nonetheless, working in non-contractor companies provides a viable alternative for women engineers who want to have successful careers in the Thai construction industry.

  14. Laser Direct Writing of Idealized Cellular and Biologic Constructs for Tissue Engineering and Regenerative Medicine

    Science.gov (United States)

    Schiele, Nathan R.; Corr, David T.; Chrisey, Douglas B.

    Conventional tissue engineering typically involves homogenously seeding cells into a scaffold, then manipulating the scaffold either mechanically, using bioreactors, or chemically, using growth factors, in an attempt to tailor the mechanical and biological properties of the engineered tissue. The material composition of the scaffold gives the construct its initial strength; then the scaffold either remodels or dissolves when implanted in the body. An ideal tissue replacement scaffold would be biocompatible, biodegradable, implantable, and would match the strength of the tissue it is replacing, and would remodel by natural mechanisms [1]. Finding or creating scaffold materials that meet all these specifications while providing an environment for cell attachment and proliferation is one of the main goals of conventional tissue engineering. Popular current scaffold materials include poly-l-lactic acid (PLLA) [2] and collagen [3]. Typically, the utilization of scaffolds in tissue engineering employs a top-down approach in which cells are seeded homogenously into the scaffold, then incubated in vitro prior to implantation. Scaffold properties, such as geometric dimensions (e.g., thickness) and cellular in-growth, are limited by the diffusion of nutrients, since these scaffolds do not incorporate vascular structures to transport nutrients and remove wastes deep into the scaffold as in native tissue [4]. Although seeded scaffolds have proven successful in some cases, there remains the need to have greater control of cell placement as well as the placement of additional features such as vascular structures, multiple cell types, growth factors, and extracellular matrix proteins that will aid in the fabrication of the next generation of engineered tissues.

  15. Current strategies of tissue engineering in talus chondral defects.

    Science.gov (United States)

    Martinelli, Niccolo; Bonifacini, Carlo; Longo, Umile Giuseppe; Marinozzi, Andrea; Florio, Pino; Khan, Wasim S; Denaro, Vincenzo

    2013-05-01

    Due to the nature of articular cartilage of being poorly vascularized the capabilities of self repair are limited. Mesenchymal stem cells transplantation is a modern technique which has been developed after the high success rates obtained by microfracturing and drilling techniques which promote the release of growth factors and the infiltration of bone marrow derived cells in the lesion. In order to increase the concentration of bone marrow derived cells appropriate devices, the scaffolds, are necessary. These three dimensional constructs mimic the physiological ambient of chondrogenesis.The race for new scaffold materials, which will show high biocompatibility to prevent inflammatory response, high cellular adhesion properties with three dimensional architecture, high bioactivity to deliver growth factor appropriately and possibly high biodegrability has just begun. New studies will concentrate on the role, on the interaction and on the temporal sequence of growth factors to improve ostheocondral differentiation, but the necessity to increase the number of clinical studies with more patients and longer follow ups seems mandatory. The aim of this review is to update and summarise the evidence-based knowledge of treatment of talus chondral defect with new tissue engineering techniques.

  16. Computational model-informed design and bioprinting of cell-patterned constructs for bone tissue engineering.

    Science.gov (United States)

    Carlier, Aurélie; Skvortsov, Gözde Akdeniz; Hafezi, Forough; Ferraris, Eleonora; Patterson, Jennifer; Koç, Bahattin; Van Oosterwyck, Hans

    2016-05-17

    Three-dimensional (3D) bioprinting is a rapidly advancing tissue engineering technology that holds great promise for the regeneration of several tissues, including bone. However, to generate a successful 3D bone tissue engineering construct, additional complexities should be taken into account such as nutrient and oxygen delivery, which is often insufficient after implantation in large bone defects. We propose that a well-designed tissue engineering construct, that is, an implant with a specific spatial pattern of cells in a matrix, will improve the healing outcome. By using a computational model of bone regeneration we show that particular cell patterns in tissue engineering constructs are able to enhance bone regeneration compared to uniform ones. We successfully bioprinted one of the most promising cell-gradient patterns by using cell-laden hydrogels with varying cell densities and observed a high cell viability for three days following the bioprinting process. In summary, we present a novel strategy for the biofabrication of bone tissue engineering constructs by designing cell-gradient patterns based on a computational model of bone regeneration, and successfully bioprinting the chosen design. This integrated approach may increase the success rate of implanted tissue engineering constructs for critical size bone defects and also can find a wider application in the biofabrication of other types of tissue engineering constructs.

  17. The current state of computing in building design and construction

    DEFF Research Database (Denmark)

    Sørensen, Lars Schiøtt; Andersen, Tom

    1996-01-01

    An exhaustive IT-survey is made in the Danish construction industry in 1995. The outcome of this survey is outlined for a selected number of issues, such as number and types of CAD-systems, data base systems, networking etc. The survey shows, that the use of IT is massive. A detailed investigation...... in relation to AI-based systems is presented. This indicates that AI-based systems/approaches have not yet penetrated in the Danish construction industry. Determinants relevant to technology penetration are described, and the immediate potential for AI-penetration are discussed and compared with the actual...... status. Finally, we conclude that there is a severe lack of awareness about AI-systems in the building sector....

  18. Planning and Selection of Heavy Construction Equipment in Civil Engineering

    Directory of Open Access Journals (Sweden)

    Mr. Nilesh D. Chinchore

    2014-04-01

    Full Text Available Construction equipment planning and selection plays crucial role for the success of construction firms.Inadequate manual processes of equipmentplanning and selection and the subjective decisions of equipment managers usually result in major losses in construction firms. An indispensable item of resources, it produces output at accelerated speed, enables completion of task in limited time. Equipment saves manpower, which is becoming costly and more demanding day by day. Equipment improves quality, productivity and safety. Construction equipment planning aims at identifying construction equipment for executing project tasks, assessing equipment performance capability, forecasting date wise requirement of number and type of equipment and finally participating in the selection of equipment to be acquired. To derive full benefits from the equipment, there should be proper selection and good planning of its operations. This paper deals with the planning and selection procedure for equipment adopted by a company to achieve its objective of timely project completion.

  19. Ultrafast Band Engineering and Transient Spin Currents in Antiferromagnetic Oxides.

    Science.gov (United States)

    Gu, Mingqiang; Rondinelli, James M

    2016-04-29

    We report a dynamic structure and band engineering strategy with experimental protocols to induce indirect-to-direct band gap transitions and coherently oscillating pure spin-currents in three-dimensional antiferromagnets (AFM) using selective phononic excitations. In the Mott insulator LaTiO3, we show that a photo-induced nonequilibrium phonon mode amplitude destroys the spin and orbitally degenerate ground state, reduces the band gap by 160 meV and renormalizes the carrier masses. The time scale of this process is a few hundreds of femtoseconds. Then in the hole-doped correlated metallic titanate, we show how pure spin-currents can be achieved to yield spin-polarizations exceeding those observed in classic semiconductors. Last, we demonstrate the generality of the approach by applying it to the non-orbitally degenerate AFM CaMnO3. These results advance our understanding of electron-lattice interactions in structures out-of-equilibrium and establish a rational framework for designing dynamic phases that may be exploited in ultrafast optoelectronic and optospintronic devices.

  20. Difference equations of quantum current operators and quantum parafermion construction

    CERN Document Server

    Ding, J; Ding, Jintai; Feigin, Boris

    1996-01-01

    For the current realization of the affine quantum groups, a simple comultiplication for the quantum current operators was given by Drinfeld. With this comultiplication, we prove that, for the integrable modules of $U_q(\\hat x^\\pm(zq^{\\pm 2k})$ are vertex operators satisfying certain q-difference equations, and we derive the quantum parafermions of $U_q(\\hat {\\frak sl}(2))$.

  1. Current status of duplex surface engineered Ti-based materials

    Institute of Scientific and Technical Information of China (English)

    T.Bell

    2004-01-01

    Industrial exploitation of the high specific strength and corrosion resistance of titanium were dominated historically by the technological advances which have been made in gas-turbine engine and aircraft components. Realization of the possible benefits in general engineering has been limited by the absence of any proven and reliable means of overcoming the poor wear resistance and galling tendency suffered by titanium alloys when in contact with other materials. This problem can only be addressed by optimizing and demonstrating industrially viable surface engineering processes for titanium in general engineering. The status of single and duplex surface engineering systems are reviewed. In addition, in order to fully realize the potential of advanced surface engineering of titanium components contact mechanics models are developed to enable the automotive engineers to design dynamically the loaded automotive engine and transmission components.

  2. 76 FR 28333 - Electric Engineering, Architectural Services, Design Policies and Construction Standards

    Science.gov (United States)

    2011-05-17

    ... Engineering, Architectural Services, Design Policies and Construction Standards AGENCY: Rural Utilities..., ARCHITECTURAL SERVICES AND DESIGN POLICIES AND PROCEDURES 1. The authority citation for part 1724 continues to... architectural services for transactions above the established threshold dollar levels (``threshold levels...

  3. Current Reports: Educating Scientists and Engineers: The View from OTA.

    Science.gov (United States)

    Morgan, Robert P.

    1989-01-01

    Compares two engineering education reports which urge the following needs and emphases: attract and retain minorities, retain students already in engineering school, and allow students to enter the engineering program at various levels. Criticizes the Office of Technology Assessment's report and supplies prescriptions for the future. (MVL)

  4. A data-driven approach to reverse engineering customer engagement models: towards functional constructs.

    Directory of Open Access Journals (Sweden)

    Natalie Jane de Vries

    Full Text Available Online consumer behavior in general and online customer engagement with brands in particular, has become a major focus of research activity fuelled by the exponential increase of interactive functions of the internet and social media platforms and applications. Current research in this area is mostly hypothesis-driven and much debate about the concept of Customer Engagement and its related constructs remains existent in the literature. In this paper, we aim to propose a novel methodology for reverse engineering a consumer behavior model for online customer engagement, based on a computational and data-driven perspective. This methodology could be generalized and prove useful for future research in the fields of consumer behaviors using questionnaire data or studies investigating other types of human behaviors. The method we propose contains five main stages; symbolic regression analysis, graph building, community detection, evaluation of results and finally, investigation of directed cycles and common feedback loops. The 'communities' of questionnaire items that emerge from our community detection method form possible 'functional constructs' inferred from data rather than assumed from literature and theory. Our results show consistent partitioning of questionnaire items into such 'functional constructs' suggesting the method proposed here could be adopted as a new data-driven way of human behavior modeling.

  5. A data-driven approach to reverse engineering customer engagement models: towards functional constructs.

    Science.gov (United States)

    de Vries, Natalie Jane; Carlson, Jamie; Moscato, Pablo

    2014-01-01

    Online consumer behavior in general and online customer engagement with brands in particular, has become a major focus of research activity fuelled by the exponential increase of interactive functions of the internet and social media platforms and applications. Current research in this area is mostly hypothesis-driven and much debate about the concept of Customer Engagement and its related constructs remains existent in the literature. In this paper, we aim to propose a novel methodology for reverse engineering a consumer behavior model for online customer engagement, based on a computational and data-driven perspective. This methodology could be generalized and prove useful for future research in the fields of consumer behaviors using questionnaire data or studies investigating other types of human behaviors. The method we propose contains five main stages; symbolic regression analysis, graph building, community detection, evaluation of results and finally, investigation of directed cycles and common feedback loops. The 'communities' of questionnaire items that emerge from our community detection method form possible 'functional constructs' inferred from data rather than assumed from literature and theory. Our results show consistent partitioning of questionnaire items into such 'functional constructs' suggesting the method proposed here could be adopted as a new data-driven way of human behavior modeling.

  6. Proposal for the increase of the contract amounts for LHC civil engineering construction and civil engineering consultancy contracts

    CERN Document Server

    2001-01-01

    This document concerns the increase of the contract amounts for LHC civil engineering construction contracts and civil engineering consultancy contracts. The Finance Committee is invited to agree to the increase of the contract amounts with: - the joint venture TEERAG-ASDAG (AT), C. BARESEL (DE) and LOCHER (CH) for civil engineering construction, package 1, for a revised total amount of 91 500 000 Swiss francs, subject to revision; - the joint venture EDF (FR) and KNIGHT&PIESOLD (GB) for the provision of civil engineering consultancy services, package 1, for a revised total amount of 14 400 000 Swiss francs, subject to revision; - the joint venture TAYLOR WOODROW (GB), AMEC (GB) and SPIE BATIGNOLLES (FR) for civil engineering construction, package 3a, for a revised total amount of 118 000 000 Swiss francs, subject to revision; - the joint venture BROWN&ROOT (GB), INTECSA (ES) and HIDROTECNICA (PT) for the provision of civil engineering consultancy services, package 3, for a revised total amount of 14 ...

  7. A Novel Human Tissue-Engineered 3-D Functional Vascularized Cardiac Muscle Construct

    Science.gov (United States)

    Valarmathi, Mani T.; Fuseler, John W.; Davis, Jeffrey M.; Price, Robert L.

    2017-01-01

    Organ tissue engineering, including cardiovascular tissues, has been an area of intense investigation. The major challenge to these approaches has been the inability to vascularize and perfuse the in vitro engineered tissue constructs. Attempts to provide oxygen and nutrients to the cells contained in the biomaterial constructs have had varying degrees of success. The aim of this current study is to develop a three-dimensional (3-D) model of vascularized cardiac tissue to examine the concurrent temporal and spatial regulation of cardiomyogenesis in the context of postnatal de novo vasculogenesis during stem cell cardiac regeneration. In order to achieve the above aim, we have developed an in vitro 3-D functional vascularized cardiac muscle construct using human induced pluripotent stem cell-derived embryonic cardiac myocytes (hiPSC-ECMs) and human mesenchymal stem cells (hMSCs). First, to generate the prevascularized scaffold, human cardiac microvascular endothelial cells (hCMVECs) and hMSCs were co-cultured onto a 3-D collagen cell carrier (CCC) for 7 days under vasculogenic culture conditions. In this milieu, hCMVECs/hMSCs underwent maturation, differentiation, and morphogenesis characteristic of microvessels, and formed extensive plexuses of vascular networks. Next, the hiPSC-ECMs and hMSCs were co-cultured onto this generated prevascularized CCCs for further 7 or 14 days in myogenic culture conditions. Finally, the vascular and cardiac phenotypic inductions were analyzed at the morphological, immunological, biochemical, molecular, and functional levels. Expression and functional analyses of the differentiated cells revealed neo-angiogenesis and neo-cardiomyogenesis. Thus, our unique 3-D co-culture system provided us the apt in vitro functional vascularized 3-D cardiac patch that can be utilized for cellular cardiomyoplasty. PMID:28194397

  8. AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XXIX, REVIEWING THE CONSTRUCTION OF ENGINE COMPONENTS.

    Science.gov (United States)

    Human Engineering Inst., Cleveland, OH.

    THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO PROVIDE A REVIEW OF THE CONSTRUCTION AND OPERATION OF DIESEL ENGINE COMPONENTS. TOPICS ARE STATIONARY PARTS, ENGINE MOVING PARTS, PISTON RINGS, AND CONNECTING RODS AND PISTON PINS. THE MODULE CONSISTS OF AN INSTRUCTOR'S GUIDE, TRANSPARENCIES, A LIST OF SUGGESTED SUPPLEMENTARY MATERIALS, AND TRAINEE…

  9. Current Neural and Behavioral Dimensional Constructs across Mood Disorders.

    Science.gov (United States)

    Langenecker, Scott A; Jacobs, Rachel H; Passarotti, Alessandra M

    2014-09-01

    Our understanding of the underlying neurobiology for mood disorders is still limited. We present an integrated model for conceptualizing and understanding mood disorders drawing upon a broad literature pertinent to mood disorders. The integrated model of emotion processing and regulation incorporates the linguistic constructs of the Research Domain Criteria (RDoC) initiative. In particular, we focus on the Positive Valence domain/circuit (PVC), highlighting recent reward research and the Negative Valence domain/circuit (NVC), highlighting rumination. Furthermore, we also illustrate the Cognitive Control and Problem Solving (CCaPS) circuit, which is heavily involved in emotion regulation, as well as the default mode network (DMN) and interactions between circuits. We conclude by proposing methods for addressing challenges in the developmental study of mood disorders including using high-risk design that incorporates risk for many disorders.

  10. The Pergau hydroelectric project. Pt. 2: Civil engineering construction

    Energy Technology Data Exchange (ETDEWEB)

    McEwan, E.; Idiculla, J.; Patel, R. [Balfour Beatty Cementation Joint Venture, Sidcup (United Kingdom)

    1997-09-01

    The Pergau Hydroelectric Project was built as a design and construct contract in Northern Peninsular Malaysia by an Anglo-Malaysian joint venture with funding assistance provided by the British Government. The project is located approximately 100 km west of the Kelantan State capital of Kota Bharu. This paper describes the contractor`s mobilization for the 600 MW hydroelectric project and the general construction requirements for the project. Although each section of the works had its own particular problems of construction, this paper concentrates on the following three areas that were critical in meeting the key dates for completion: the powerhouse and power tunnels; the power shaft; the Kuala Yong dam. It also includes a brief description of the tunnelling methods used. (author)

  11. 48 CFR 853.236 - Construction and architect-engineer contracts.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Construction and architect-engineer contracts. 853.236 Section 853.236 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS CLAUSES AND FORMS FORMS Prescription of Forms 853.236 Construction and...

  12. 48 CFR 53.236 - Construction and architect-engineer contracts.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Construction and architect-engineer contracts. 53.236 Section 53.236 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND FORMS FORMS Prescription of Forms 53.236 Construction and...

  13. The Local Construction of the Asymmetrical Power Relationship in Teamwork among Engineers

    Science.gov (United States)

    Vickers, Caroline H.

    2010-01-01

    The purpose of this article is to examine local, interactional processes associated with the construction of power asymmetries in collaborative teamwork among engineering students. To explore the construction of power asymmetries at the micro-interactional level, this article examines a corpus consisting of about 150,000 words in which seven teams…

  14. Geocontainers in road building and hydraulic engineering construction

    OpenAIRE

    2011-01-01

    Geocontainers are structural loops made of high-strength geotextile. In the course of construction they are filled by ground or inert material on-site. The geomatrix is the next step in the development of geocontainers. It is the cellular structure made of geotextile, the cellules are connected by lacing or by thermal welding.The aim of the article is to acquaint the reader with this type of geomaterials, possibilities of its use in different areas of construction.The technology of using geoc...

  15. Constructing an Efficient Self-Tuning Aircraft Engine Model for Control and Health Management Applications

    Science.gov (United States)

    Armstrong, Jeffrey B.; Simon, Donald L.

    2012-01-01

    Self-tuning aircraft engine models can be applied for control and health management applications. The self-tuning feature of these models minimizes the mismatch between any given engine and the underlying engineering model describing an engine family. This paper provides details of the construction of a self-tuning engine model centered on a piecewise linear Kalman filter design. Starting from a nonlinear transient aerothermal model, a piecewise linear representation is first extracted. The linearization procedure creates a database of trim vectors and state-space matrices that are subsequently scheduled for interpolation based on engine operating point. A series of steady-state Kalman gains can next be constructed from a reduced-order form of the piecewise linear model. Reduction of the piecewise linear model to an observable dimension with respect to available sensed engine measurements can be achieved using either a subset or an optimal linear combination of "health" parameters, which describe engine performance. The resulting piecewise linear Kalman filter is then implemented for faster-than-real-time processing of sensed engine measurements, generating outputs appropriate for trending engine performance, estimating both measured and unmeasured parameters for control purposes, and performing on-board gas-path fault diagnostics. Computational efficiency is achieved by designing multidimensional interpolation algorithms that exploit the shared scheduling of multiple trim vectors and system matrices. An example application illustrates the accuracy of a self-tuning piecewise linear Kalman filter model when applied to a nonlinear turbofan engine simulation. Additional discussions focus on the issue of transient response accuracy and the advantages of a piecewise linear Kalman filter in the context of validation and verification. The techniques described provide a framework for constructing efficient self-tuning aircraft engine models from complex nonlinear

  16. Current State and Development Strategy of CNPC Engineering Technology Service

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Challenges to CNPC engineering technology service Internal contraction and problems (1) Pricing mechanism for technology service. CNPC engineering technology companies have been under deficit for many years after restructuring, and eight subordinate companies lost 239 million RMB in 2008 and even 770 million RMB in 2009.

  17. Tissue Engineering-Current Challenges and Expanding Opportunities

    Science.gov (United States)

    Griffith, Linda G.; Naughton, Gail

    2002-02-01

    Tissue engineering can be used to restore, maintain, or enhance tissues and organs. The potential impact of this field, however, is far broader-in the future, engineered tissues could reduce the need for organ replacement, and could greatly accelerate the development of new drugs that may cure patients, eliminating the need for organ transplants altogether.

  18. Current Developments in the French Engineering Education System

    Science.gov (United States)

    Lemaître, Denis

    2017-01-01

    The French engineering education system has been established in quite a different way from others in Europe, such as the German and British systems, for instance. Due to both the whole state system and the private initiatives during the industrial revolution, the engineering education system today is composed of a large number (nearly 200) of…

  19. Methodology discourses as boundary work in the construction of engineering education.

    Science.gov (United States)

    Beddoes, Kacey

    2014-04-01

    Engineering education research is a new field that emerged in the social sciences over the past 10 years. This analysis of engineering education research demonstrates that methodology discourses have played a central role in the construction and development of the field of engineering education, and that they have done so primarily through boundary work. This article thus contributes to science and technology studies literature by examining the role of methodology discourses in an emerging social science field. I begin with an overview of engineering education research before situating the case within relevant bodies of literature on methodology discourses and boundary work. I then identify two methodology discourses--rigor and methodological diversity--and discuss how they contribute to the construction and development of engineering education research. The article concludes with a discussion of how the findings relate to prior research on methodology discourses and boundary work and implications for future research.

  20. The Stirling engine. Simply explained, easily constructed. 9. rev. and enl. ed.; Der Stirlingmotor. Einfach erklaert und leicht gebaut

    Energy Technology Data Exchange (ETDEWEB)

    Viebach, Dieter

    2010-07-01

    Subsequently to a easily comprehensively description of the function and characteristics of Stirling engines, the author of the book under consideration describes the construction of a model Stirling engine on the basis of clear construction drawings. A delicacy for experienced modelers: The 'amazing model', a miniature Stirling engine consisting of beverage cans, has been running with the warmth of the human hand. Even in this technically demanding model, the construction will be described accurately by detailed construction drawings.

  1. Dual-Scale Polymeric Constructs as Scaffolds for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Federica Chiellini

    2011-03-01

    Full Text Available This research activity was aimed at the development of dual-scale scaffolds consisting of three-dimensional constructs of aligned poly(ε-caprolactone (PCL microfilaments and electrospun poly(lactic-co-glycolic acid (PLGA fibers. PCL constructs composed by layers of parallel microsized filaments (0/90° lay-down pattern, with a diameter of around 365 μm and interfilament distance of around 191 μm, were produced using a melt extrusion-based additive manufacturing technique. PLGA electrospun fibers with a diameter of around 1 μm were collected on top of the PCL constructs with different thicknesses, showing a certain degree of alignment. Cell culture experiments employing the MC3T3 murine preosteoblast cell line showed good cell viability and adhesion on the dual-scale scaffolds. In particular, the influence of electrospun fibers on cell morphology and behavior was evident, as well as in creating a structural bridging for cell colonization in the interfilament gap.

  2. Discursive Constructions of Design and Implications for Engineering Education

    DEFF Research Database (Denmark)

    Petersen, Rikke Premer

    Recognition of design discourses at play in professional practice is key when discussing ways to reintroduce designerly ways in engineering education. This paper outlines three design discourses discussed in literature and mirroring contemporary design practice: Viewing ‘design as art’ upholds...... traditional ties to the arts and craft tradition, where individual designers work with tangible form and aesthetics. Perceiving ‘design as problem solving’ focuses on the process viewed as a collective search for solutions. In ‘design as dialogue’ this is extended to a reflective practice where the designer...

  3. A contribution to the lexis of construction engineering textbooks: the case of 'building' and 'construction'

    Directory of Open Access Journals (Sweden)

    Concepción Orna Montesinos

    2008-10-01

    Full Text Available The integration of a genre-based and a corpus-based instruction in ESP learning (Swales, 1990; Tribble, 2000; Ferguson, 2001; Flowerdew, 2005 has proved to be a suitable theoretical framework for describing the lexis of construction and architecture university textbooks, such as the sample compiled in the Construction Textbooks Corpus (CTC. This paper is a contribution to the study of the formal and semantic profiles of the lexis of this particular genre type and, by way of illustration, focuses on the case study of the lemmas build and construct. From a formal standpoint, the CTC reveals that the noun building (the first content word in the CTC is six times more frequent than the verb build, and the noun construction (third in frequency is eleven times more frequent than the verb construct. Semantically, the corpus displays a prevalence of technical meanings which refer to building and construction as the activity or business of erecting edifices or structures. By observing the lexical profile of construction textbooks, this paper will finally consider possible teaching/learning implications.

  4. Current distribution and enhancement of the engineering critical current density in multifilament Bi-2223 tapes

    DEFF Research Database (Denmark)

    Wang, W.G.; Jensen, M.B.; Kindl, B.;

    2000-01-01

    The spatial distribution of the critical current density (Jc) and engineering critical current density (Je) along the tape width direction was studied by a cutting technique on Bi-2223 multifilamentary tapes. In general, an increase of Jc towards the centre of the tape was measured. We attribute...... this tendency to the stress-strain experienced in the tape during the rolling process. Jc of 50 kA/cm2 and Jeof 18 kA/cm2 was measured at the centre part (185 μm wide and 200 μm thick) of a tape cut from a 500 meters long tape (average Je of 8 kA/cm2). The low Jc of the edge part is a result of the porous...... microstructure with a great amount of secondary phases. Local variation of Jc was measured within the centre segment of the tape. This indicates the influence of other factors on Jc, such as filament shape, connectivity of the filaments, and sausaging. Enhancement of Je has been pursued in which average Je of 12...

  5. Construction of an environmental safe Bacillus thuringiensis engineered strain against Coleoptera.

    Science.gov (United States)

    Yu, Yajun; Yuan, Yihui; Gao, Meiying

    2016-05-01

    Cloning of new toxic genes from Bacillus thuringiensis (Bt) and construction of Bt engineered strains are two key strategies for bio-control of coleopteran pests in agriculture and forestry. In this study, we cloned a new cry3Aa-type gene, cry3Aa8, from wild Bt strain YC-03 against coleopteran, and constructed a Bt engineered strain, ACE-38, containing insecticidal protein-encoding gene cry3Aa8. The engineered strain, with almost four times of Cry3Aa yield compared with strain YC-03, was an antibiotic marker-free strain. Though no selective pressure was presented in the medium, cry3Aa8 in the engineered strain ACE-38 remained stable. The yield of Cry3Aa by strain ACE-38 reached 2.09 mg/ml in the optimized fermentation medium. The activity of strain ACE-38 against Plagiodera versicolora was tested, and the LC50 of ACE-38 cultures in the optimized fermentation medium was 1.13 μl/ml. Strain ACE-38 is a non-antibiotic Bt engineered strain with high Chrysomelidae toxicity and exhibits good fermentation property. The modified indigenous site-specific recombination system constructed in this study might be useful for the construction of Bt engineered strains containing genes that cannot be expressed in the indigenous site-specific recombination system using plasmid pBMB1205R.

  6. FPGA Simulation Engine for Customized Construction of Neural Microcircuits.

    Science.gov (United States)

    Blair, Hugh T; Cong, Jason; Wu, Di

    2013-04-01

    In this paper we describe an FPGA-based platform for high-performance and low-power simulation of neural microcircuits composed from integrate-and-fire (IAF) neurons. Based on high-level synthesis, our platform uses design templates to map hierarchies of neuron model to logic fabrics. This approach bypasses high design complexity and enables easy optimization and design space exploration. We demonstrate the benefits of our platform by simulating a variety of neural microcircuits that perform oscillatory path integration, which evidence suggests may be a critical building block of the navigation system inside a rodent's brain. Experiments show that our FPGA simulation engine for oscillatory neural microcircuits can achieve up to 39× speedup compared to software benchmarks on commodity CPU, and 232× energy reduction compared to embedded ARM core.

  7. Functional evaluation of artificial skeletal muscle tissue constructs fabricated by a magnetic force-based tissue engineering technique.

    Science.gov (United States)

    Yamamoto, Yasunori; Ito, Akira; Fujita, Hideaki; Nagamori, Eiji; Kawabe, Yoshinori; Kamihira, Masamichi

    2011-01-01

    Skeletal muscle tissue engineering is currently applied in a variety of research fields, including regenerative medicine, drug screening, and bioactuator development, all of which require the fabrication of biomimic and functional skeletal muscle tissues. In the present study, magnetite cationic liposomes were used to magnetically label C2C12 myoblast cells for the construction of three-dimensional artificial skeletal muscle tissues by an applied magnetic force. Skeletal muscle functions, such as biochemical and contractile properties, were evaluated for the artificial tissue constructs. Histological studies revealed that elongated and multinucleated myotubes were observed within the tissue. Expression of muscle-specific markers, such as myogenin, myosin heavy chain and tropomyosin, were detected in the tissue constructs by western blot analysis. Further, creatine kinase activity increased during differentiation. In response to electric pulses, the artificial tissue constructs contracted to generate a physical force (the maximum twitch force, 33.2 μN [1.06 mN/mm2]). Rheobase and chronaxie of the tissue were determined as 4.45 V and 0.72 ms, respectively. These results indicate that the artificial skeletal muscle tissue constructs fabricated in this study were physiologically functional and the data obtained for the evaluation of their functional properties may provide useful information for future skeletal muscle tissue engineering studies.

  8. The Strategy of Management Тraining in the Construction Engineering

    Directory of Open Access Journals (Sweden)

    Khripko Elena

    2017-01-01

    Full Text Available The operating efficiency of leaders in the construction industry is largely determined by the level of formation of managerial skills. Along with this, it is stated that the process of formation and development of managerial skills for leaders in the construction engineering is attended by a number of difficulties and frequently doesn’t make it past the threshold. This paper formulates a new approach in the formation of managerial skills of leaders in the construction engineering. The cross-sectoral assessment of managerial skills featuring the heads of the construction engineering and other industries, such as energy, metallurgy, showed low-performing managerial skills for the heads of the construction industry. The reasons of the formation of low-performing managerial skills in this article are referred to as peculiar features of organizational behavior in the construction engineering, in particular an imminent regression in the leader-follower system. Based on the results of the research conducted, the similarity of issues in regard to managerial skills in these areas is inherent in key differences in the formulation of priorities of corporate competencies.

  9. GOVERNMENT EXPENDITURE ON ENGINEERING CONSTRUCTION, COMMUNICATION AND TRANSPORTATION: EVALUATION OF IMPACT ON ECONOMIC GROWTH IN NIGERIA

    Directory of Open Access Journals (Sweden)

    ALAMEZIEM KELECHI STANLEY

    2012-04-01

    Full Text Available This work tries to assess the impact of government investment in engineering construction, communication technology and transportation on economic growth in Nigeria. One null hypothesis guided the study and data was collected from 1977 to 2008 from Central Bank of Nigeria statistical bulletin. Data were analysed using regression, F and t tests, stationary and co-integration tests. Results revealed that increases in government expenditure in engineering construction impacted more significantly on economic growth than their expenditureon transport and communication. Increased expenditure on all sectors was recommended especially on engineering construction. In addition policy modifications are needed to ensure that government expenditure on the transportation and communication sector achieve greater impacts on economic growth.

  10. Cardiovascular Bio-Engineering: Current State of the Art.

    Science.gov (United States)

    Simon-Yarza, Teresa; Bataille, Isabelle; Letourneur, Didier

    2017-04-01

    Despite the introduction of new drugs and innovative devices contributing in the last years to improve patients' quality of life, morbidity and mortality from cardiovascular diseases remain high. There is an urgent need for addressing the underlying problem of the loss of cardiac or vascular tissues and therefore developing new therapies. Autologous vascular transplants are often limited by poor quality of donor sites and heart organ transplantation by donor shortage. Vascular and cardiac tissue engineering, whose aim is to repair or replace cardiovascular tissues by the use of cells, engineering and materials, as well as biochemical and physicochemical factors, appears in this scenario as a promising tool to repair the damaged hearts and vessels. We will present a general overview on the fundamentals in the area of cardiac and vascular tissue engineering as well as on the latest progresses and challenges.

  11. Googling social interactions: web search engine based social network construction.

    Science.gov (United States)

    Lee, Sang Hoon; Kim, Pan-Jun; Ahn, Yong-Yeol; Jeong, Hawoong

    2010-07-21

    Social network analysis has long been an untiring topic of sociology. However, until the era of information technology, the availability of data, mainly collected by the traditional method of personal survey, was highly limited and prevented large-scale analysis. Recently, the exploding amount of automatically generated data has completely changed the pattern of research. For instance, the enormous amount of data from so-called high-throughput biological experiments has introduced a systematic or network viewpoint to traditional biology. Then, is "high-throughput" sociological data generation possible? Google, which has become one of the most influential symbols of the new Internet paradigm within the last ten years, might provide torrents of data sources for such study in this (now and forthcoming) digital era. We investigate social networks between people by extracting information on the Web and introduce new tools of analysis of such networks in the context of statistical physics of complex systems or socio-physics. As a concrete and illustrative example, the members of the 109th United States Senate are analyzed and it is demonstrated that the methods of construction and analysis are applicable to various other weighted networks.

  12. Tissue engineered fetal skin constructs for pediatric burns

    Science.gov (United States)

    Norbury, William B; Jeschke, Marc G; Herndon, David N

    2005-01-01

    The management of patients with partial thickness (second degree) burns is problematic due to the different treatments needed for varying depths of injury. A report recently published in The Lancet describes a novel treatment for deep second degree burns using a fetal skin construct (FSC). The authors included eight pediatric patients with small second degree burns. They showed that FSCs reduced the need for autografting of deep second degree burns, with little hypertrophy of new skin and no skin contraction. This technology is new and exciting, but in our opinion several issues must be addressed before FSCs can enter the clinical arena. All of the patients were included in the treatment group, and therefore no comparison with conventional skin substitutes was possible. There is no mention of the use of laser Doppler in any initial assessment of patients. The debridement carried out before application of the FSC is not elaborated upon, and the surface areas involved in the study were very small in most cases, which limits the relevance to patients with larger burns. The use of FSCs gives us an additional option in a range of possible treatments for this notoriously difficult-to-treat patient group. PMID:16356232

  13. Nonlinear optical molecular imaging enables metabolic redox sensing in tissue-engineered constructs

    Science.gov (United States)

    Chen, Leng-Chun; Lloyd, William R.; Wilson, Robert H.; Kuo, Shiuhyang; Marcelo, Cynthia L.; Feinberg, Stephen E.; Mycek, Mary-Ann

    2011-07-01

    Tissue-engineered constructs require noninvasive monitoring of cellular viability prior to implantation. In a preclinical study on human Ex Vivo Produced Oral Mucosa Equivalent (EVPOME) constructs, nonlinear optical molecular imaging was employed to extract morphological and functional information from intact constructs. Multiphoton excitation fluorescence images were acquired using endogenous fluorescence from cellular nicotinamide adenine dinucleotide phosphate [NAD(P)H] and flavin adenine dinucleotide (FAD). The images were analyzed to report quantitatively on tissue structure and metabolism (redox ratio). Both thickness variations over time and cell distribution variations with depth were identified, while changes in redox were quantified. Our results show that nonlinear optical molecular imaging has the potential to visualize and quantitatively monitor the growth and viability of a tissue-engineered construct over time.

  14. Protein engineering for metabolic engineering: current and next-generation tools

    Science.gov (United States)

    Marcheschi, Ryan J.; Gronenberg, Luisa S.; Liao, James C.

    2014-01-01

    Protein engineering in the context of metabolic engineering is increasingly important to the field of industrial biotechnology. As the demand for biologically-produced food, fuels, chemicals, food additives, and pharmaceuticals continues to grow, the ability to design and modify proteins to accomplish new functions will be required to meet the high productivity demands for the metabolism of engineered organisms. This article reviews advances of selecting, modeling, and engineering proteins to improve or alter their activity. Some of the methods have only recently been developed for general use and are just beginning to find greater application in the metabolic engineering community. We also discuss methods of generating random and targeted diversity in proteins to generate mutant libraries for analysis. Recent uses of these techniques to alter cofactor use, produce non-natural amino acids, alcohols, and carboxylic acids, and alter organism phenotypes are presented and discussed as examples of the successful engineering of proteins for metabolic engineering purposes. PMID:23589443

  15. Protein engineering for metabolic engineering: current and next-generation tools.

    Science.gov (United States)

    Marcheschi, Ryan J; Gronenberg, Luisa S; Liao, James C

    2013-05-01

    Protein engineering in the context of metabolic engineering is increasingly important to the field of industrial biotechnology. As the demand for biologically produced food, fuels, chemicals, food additives, and pharmaceuticals continues to grow, the ability to design and modify proteins to accomplish new functions will be required to meet the high productivity demands for the metabolism of engineered organisms. We review advances in selecting, modeling, and engineering proteins to improve or alter their activity. Some of the methods have only recently been developed for general use and are just beginning to find greater application in the metabolic engineering community. We also discuss methods of generating random and targeted diversity in proteins to generate mutant libraries for analysis. Recent uses of these techniques to alter cofactor use; produce non-natural amino acids, alcohols, and carboxylic acids; and alter organism phenotypes are presented and discussed as examples of the successful engineering of proteins for metabolic engineering purposes.

  16. Constructing engineers through practice: Gendered features of learning and identity development

    Science.gov (United States)

    Tonso, Karen L.

    How do women and men student engineers develop an engineering identity (a sense of belonging, or not), while practicing "actual" engineering? What are the influences of gender, learning and knowledge, relations of power, and conceptions of equality on cultural identity development? I studied these issues in reform-minded engineering design classes, courses organized around teaching students communications, teamwork, and practical engineering. Engineering-student cultural identity categories revealed a status hierarchy, predicated on meeting "academic" criteria for excellence, and the almost total exclusion of women. While working as an engineering colleague on five student teams (three first-year and two senior) and attending their design classes, I documented how cultural identities were made evident and constructed in students' practical engineering. Design projects promoted linking academic knowledge with real-world situations, sharing responsibilities and trusting colleagues, communicating engineering knowledge to technical and non-technical members of business communities, and addressing gaps in students' knowledge. With a curriculum analysis and survey of students' perceptions of the differences between design and conventional courses, I embedded the design classes in the wider campus and found that: (1) Engineering education conferred prestige, power, and well-paying jobs on students who performed "academic" engineering, while failing to adequately encourage "actual" engineering practices. High-status student engineers were the least likely to perform "actual" engineering in design teams. (2) Engineering education advanced an ideology that encouraged its practitioners to consider men's privilege and women's invisibility normal. By making "acting like men act" the standards to which engineering students must conform, women learned to put up with oppressive treatment. Women's accepting their own mistreatment and hiding their womanhood became a condition of

  17. Constructive alignment in Computer Engineering and Informatics departments at Dalarna University : An empirical investigation

    OpenAIRE

    Memedi, Mevludin

    2015-01-01

    Background: Constructive alignment (CA) is a pedagogical approach that emphasizes the alignment between the intended learning outcomes (ILOs), teaching and learning activities (TLAs) and assessment tasks (ATs) as well as creation of a teaching/learning environment where students will be able to actively create their knowledge. Objectives: This paper aims at investigating the extent of constructively-aligned courses in Computer Engineering and Informatics department at Dalarna University, Swed...

  18. DEVELOPMENT OF ALGORITHMS OF NUMERICAL PROJECT OPTIMIZATION FOR THE CONSTRUCTION AND RECONSTRUCTION OF ENGINEERING STRUCTURES

    Directory of Open Access Journals (Sweden)

    MENEJLJUK О. І.

    2016-08-01

    Full Text Available Raising of problem. The paper analyzes the numerical optimization methods of construction projects and reconstruction of engineering structures. Purpose. Possible ways of modeling organizational and technological solutions in construction are presented. Based on the analysis the most effective method of optimization by experimental and statistical modeling with application of modern computer programs in the field of project management and mathematical statistics is selected. Conclusion. An algorithm for solving optimization problems by means of experimental and statistical modeling is developed.

  19. Segmentation Based Approach to Dynamic Page Construction from Search Engine Results

    OpenAIRE

    K.S. Kuppusamy,; Aghila, G.

    2012-01-01

    The results rendered by the search engines are mostly a linear snippet list. With the prolific increase in the dynamism of web pages there is a need for enhanced result lists from search engines in order to cope-up with the expectations of the users. This paper proposes a model for dynamic construction of a resultant page from various results fetched by the search engine, based on the web page segmentation approach. With the incorporation of personalization through user profile during the can...

  20. Increase of the contract amounts for LHC civil-engineering construction and civil-engineering consultancy contracts

    CERN Document Server

    2005-01-01

    This document concerns the increase of the contract amounts for LHC civil-engineering construction and civil-engineering consultancy, Package 2. The Finance Committee is invited to take note of the increase of the contract amounts with: - the joint venture DRAGADOS (ES) and SELI (IT) for civil-engineering construction, LHC Package 2, for an amount of 28 087 000 Swiss francs, subject to revision, in the amount previously announced to Finance Committee (CERN/FC/4516) of 132 200 000 Swiss francs, subject to revision, bringing the total to a maximum amount of 160 287 000 Swiss francs, subject to revision. - the joint venture GIBB (GB), GEOCONSULT (AT) and SGI (CH) for the provision of civil-engineering consultancy services, LHC Package 2, for an amount of 900 000 Swiss francs, subject to revision, in the amount previously announced to Finance Committee of 13 800 000 Swiss francs, subject to revision, bringing the total to a maximum amount of 14 700 000 Swiss francs, subject to revision

  1. Engineering America's Current and Future Space Transportation Systems: 50 Years of Systems Engineering Innovation for Sustainable Exploration

    Science.gov (United States)

    Dmbacher, Daniel L.; Lyles, Garry M.; McConnaughey, Paul

    2008-01-01

    Over the past 50 years, the National Aeronautics and Space Administration (NASA) has delivered space transportation solutions for America's complex missions, ranging from scientific payloads that expand knowledge, such as the Hubble Space Telescope, to astronauts and lunar rovers destined for voyages to the Moon. Currently, the venerable Space Shuttle, which has been in service since 1981, provides the United States' (U.S.) capability for both crew and heavy cargo to low-Earth orbit to' construct the International Space Station, before the Shuttle is retired in 2010. In the next decade, NASA will replace this system with a duo of launch vehicles: the Ares I Crew Launch Vehicle and the Ares V Cargo Launch Vehicle (Figure 1). The goals for this new system include increased safety and reliability coupled with lower operations costs that promote sustainable space exploration for decades to come. The Ares I will loft the Orion Crew Exploration Vehicle, while the heavy-lift Ares V will carry the Altair Lunar Lander and the equipment and supplies needed to construct a lunar outpost for a new generation of human and robotic space pioneers. This paper will provide details of the in-house systems engineering and vehicle integration work now being performed for the Ares I and planned for the Ares V. It will give an overview of the Ares I system-level test activities, such as the ground vibration testing that will be conducted in the Marshall Center's Dynamic Test Stand to verify the integrated vehicle stack's structural integrity and to validate computer modeling and simulation (Figure 2), as well as the main propulsion test article analysis to be conducted in the Static Test Stand. These activities also will help prove and refine mission concepts of operation, while supporting the spectrum of design and development work being performed by Marshall's Engineering Directorate, ranging from launch vehicles and lunar rovers to scientific spacecraft and associated experiments

  2. Biomechanical researches on tissue engineering bone constructed by deproteinated bone

    Institute of Scientific and Technical Information of China (English)

    JIAN Yue-kui; TIAN Xiao-bin; LI Qi-hong; LI Bo; PENG Zhi; ZHAO Wei-feng; WANG Yuan-zheng; YANG Zhen

    2010-01-01

    Objective:To study biomechanical changes of newly formed bones 24 weeks after repairing large defects of long bones of goats using heterogeneous deproteinated bone(DPB)prepared by modified methods as an engineering scaffold.Methods:According to a fully randomized design,18 goats were evenly divided into three groups:normal bone control group(Group A),autologous bone group(Group B)and experimental group(Group C).Each goat in Groups B and C were subjected to the periosteum and bone defect at middle-lower part of the fight tibia(20% of the whole tibia in length),followed by autologous bone or DPB plus autologous MSCs + rhBMP2 implantation,respectively and semiring slot fixation;while goats in Group A did not perform osteotomy.At 24 weeks after surgery,biomechanical tests were carried out on the tibias.Results:At 24 weeks after surgery,the results of anticompression test on tibias in three groups were recorded by a functional recorder presented as linear pressure-deformation curve.The shapes of the curves and their change tendency were similar among three groups.The ultimate pressure values were 10.74 Mpa±1.23 Mpa,10.11 Mpa±1.35 Mpa and 10.22 Mpa±1.32 Mpa and fracture compression rates were 26.82%±0.87%,27.17%±0.75% and 28.22%±1.12% in Groups A,B and C,respectively.Comparisons of anti-compression ultimate pressures and fracture compression rates among three groups demonstrated no significant difference(P_(AB)=0.415,P_(BC)=0.494).Three-point antibend test on tibias was recorded as load-deformation curves,and the shapes of the curves and their change tendency were similar among three groups.The ultimate pressure values of the anti-bend test were 481.52 N±12.45 N,478.34 N±14.68 N and 475.62 N±13.41 N and the fracture bend rates were 2.62 mm±0.12 mm,2.61 mm±0.15 mm and 2.81 mm±0.13 mm in Groups A,B and C,respectively.There was no significant difference between groups(P_(AB)=0.7,P_(BC)=0.448).The ultirates were 29.51°±1.64°,28.88°±1.46° and 28.81°±1.33

  3. Software architecture and engineering for patient records: current and future.

    Science.gov (United States)

    Weng, Chunhua; Levine, Betty A; Mun, Seong K

    2009-05-01

    During the "The National Forum on the Future of the Defense Health Information System," a track focusing on "Systems Architecture and Software Engineering" included eight presenters. These presenters identified three key areas of interest in this field, which include the need for open enterprise architecture and a federated database design, net centrality based on service-oriented architecture, and the need for focus on software usability and reusability. The eight panelists provided recommendations related to the suitability of service-oriented architecture and the enabling technologies of grid computing and Web 2.0 for building health services research centers and federated data warehouses to facilitate large-scale collaborative health care and research. Finally, they discussed the need to leverage industry best practices for software engineering to facilitate rapid software development, testing, and deployment.

  4. Growth factor stimulation improves the structure and properties of scaffold-free engineered auricular cartilage constructs.

    Directory of Open Access Journals (Sweden)

    Renata G Rosa

    Full Text Available The reconstruction of the external ear to correct congenital deformities or repair following trauma remains a significant challenge in reconstructive surgery. Previously, we have developed a novel approach to create scaffold-free, tissue engineering elastic cartilage constructs directly from a small population of donor cells. Although the developed constructs appeared to adopt the structural appearance of native auricular cartilage, the constructs displayed limited expression and poor localization of elastin. In the present study, the effect of growth factor supplementation (insulin, IGF-1, or TGF-β1 was investigated to stimulate elastogenesis as well as to improve overall tissue formation. Using rabbit auricular chondrocytes, bioreactor-cultivated constructs supplemented with either insulin or IGF-1 displayed increased deposition of cartilaginous ECM, improved mechanical properties, and thicknesses comparable to native auricular cartilage after 4 weeks of growth. Similarly, growth factor supplementation resulted in increased expression and improved localization of elastin, primarily restricted within the cartilaginous region of the tissue construct. Additional studies were conducted to determine whether scaffold-free engineered auricular cartilage constructs could be developed in the 3D shape of the external ear. Isolated auricular chondrocytes were grown in rapid-prototyped tissue culture molds with additional insulin or IGF-1 supplementation during bioreactor cultivation. Using this approach, the developed tissue constructs were flexible and had a 3D shape in very good agreement to the culture mold (average error <400 µm. While scaffold-free, engineered auricular cartilage constructs can be created with both the appropriate tissue structure and 3D shape of the external ear, future studies will be aimed assessing potential changes in construct shape and properties after subcutaneous implantation.

  5. Design of a System for Monitoring Reliability of Structures and Constructions in Civil Engineering

    Directory of Open Access Journals (Sweden)

    Tomislav S. Igić

    2011-07-01

    Full Text Available Monitoring of civil engineering structures and constructions requires techniques which can produce high precision and accuracy, reliable measurements and fast processing speed. The development of information and communication systems as well as of microprocessor controllers has enabled a creation of monitoring systems that can be used for tracking reliability of structures and constructions in civil engineering, with described key features. This paper describes in detail the architecture of the Civil Engineering Structures Reliability Monitoring (CERM system. The system has been designed for the purposes of the Technical Mechanics and Theory of Constructions Department at the Faculty of Civil Engineering and Architecture, University of Nis. Unlike general commercial monitoring systems, the CERM system has been specially designed for the purpose of reliability monitoring, and its potential will be further exploited in this paper. It is based on usage of universal microprocessor controllers Integraf of series 10X, along with specially designed software package. This system provides real time acquisition of measurements for observed civil engineering structures and analysis of received values based on developed mathematical models.

  6. Tool for Benchmarking BIM Performance of Design Engineering and Construction Firms in The Netherlands

    NARCIS (Netherlands)

    Sebastian, R.; Berlo, L. van

    2010-01-01

    Building information modelling (BIM) is becoming more and more important to manage complex communication and information sharing processes in collaborative building projects. A growing number of design, engineering and construction firms have made attempts to adopt BIM to enhance their services and

  7. Tool for Benchmarking BIM Performance of Design Engineering and Construction Firms in The Netherlands

    NARCIS (Netherlands)

    Sebastian, R.; Berlo, L. van

    2010-01-01

    Building information modelling (BIM) is becoming more and more important to manage complex communication and information sharing processes in collaborative building projects. A growing number of design, engineering and construction firms have made attempts to adopt BIM to enhance their services and

  8. Videogame Construction by Engineering Students for Understanding Modelling Processes: The Case of Simulating Water Behaviour

    Science.gov (United States)

    Pretelín-Ricárdez, Angel; Sacristán, Ana Isabel

    2015-01-01

    We present some results of an ongoing research project where university engineering students were asked to construct videogames involving the use of physical systems models. The objective is to help them identify and understand the elements and concepts involved in the modelling process. That is, we use game design as a constructionist approach…

  9. Evolutionary, Unconscious Design Support for the Architectural, Engineering and Construction Industry

    NARCIS (Netherlands)

    Van de Ruitenbeek, H.K.M.

    2012-01-01

    The Architecture, Engineering and Construction (AEC) industry is a complex system in which carpenters, structural designers, architects, modellers, cost estimators, planners, politicians and many others act apart together in project-specific virtual enterprises. There is a large amount of actors, an

  10. Facilitating Constructive Alignment in Power Systems Engineering Education Using Free and Open-Source Software

    Science.gov (United States)

    Vanfretti, L.; Milano, F.

    2012-01-01

    This paper describes how the use of free and open-source software (FOSS) can facilitate the application of constructive alignment theory in power systems engineering education by enabling the deep learning approach in power system analysis courses. With this aim, this paper describes the authors' approach in using the Power System Analysis Toolbox…

  11. The Role of Discourse in Group Knowledge Construction: A Case Study of Engineering Students

    Science.gov (United States)

    Kittleson, Julie M.; Southerland, Sherry A.

    2004-01-01

    This qualitative study examined the role of discourse (verbal elements of language) and Discourse (nonverbal elements related to the use of language, such as ways of thinking, valuing, and using tools and technologies) in the process of group knowledge construction of mechanical engineering students. Data included interviews, participant…

  12. Cell Sheet-Based Tissue Engineering for Organizing Anisotropic Tissue Constructs Produced Using Microfabricated Thermoresponsive Substrates.

    Science.gov (United States)

    Takahashi, Hironobu; Okano, Teruo

    2015-11-18

    In some native tissues, appropriate microstructures, including orientation of the cell/extracellular matrix, provide specific mechanical and biological functions. For example, skeletal muscle is made of oriented myofibers that is responsible for the mechanical function. Native artery and myocardial tissues are organized three-dimensionally by stacking sheet-like tissues of aligned cells. Therefore, to construct any kind of complex tissue, the microstructures of cells such as myotubes, smooth muscle cells, and cardiomyocytes also need to be organized three-dimensionally just as in the native tissues of the body. Cell sheet-based tissue engineering allows the production of scaffold-free engineered tissues through a layer-by-layer construction technique. Recently, using microfabricated thermoresponsive substrates, aligned cells are being harvested as single continuous cell sheets. The cell sheets act as anisotropic tissue units to build three-dimensional tissue constructs with the appropriate anisotropy. This cell sheet-based technology is straightforward and has the potential to engineer a wide variety of complex tissues. In addition, due to the scaffold-free cell-dense environment, the physical and biological cell-cell interactions of these cell sheet constructs exhibit unique cell behaviors. These advantages will provide important clues to enable the production of well-organized tissues that closely mimic the structure and function of native tissues, required for the future of tissue engineering. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Facilitating Constructive Alignment in Power Systems Engineering Education Using Free and Open-Source Software

    Science.gov (United States)

    Vanfretti, L.; Milano, F.

    2012-01-01

    This paper describes how the use of free and open-source software (FOSS) can facilitate the application of constructive alignment theory in power systems engineering education by enabling the deep learning approach in power system analysis courses. With this aim, this paper describes the authors' approach in using the Power System Analysis Toolbox…

  14. Evolutionary, Unconscious Design Support for the Architectural, Engineering and Construction Industry

    NARCIS (Netherlands)

    Van de Ruitenbeek, H.K.M.

    2012-01-01

    The Architecture, Engineering and Construction (AEC) industry is a complex system in which carpenters, structural designers, architects, modellers, cost estimators, planners, politicians and many others act apart together in project-specific virtual enterprises. There is a large amount of actors, an

  15. Public health engineering education in India: current scenario, opportunities and challenges.

    Science.gov (United States)

    Hussain, Mohammad Akhtar; Sharma, Kavya; Zodpey, Sanjay

    2011-01-01

    Public health engineering can play an important and significant role in solving environmental health issues. In order to confront public health challenges emerging out of environmental problems we need adequately trained public health engineers / environmental engineers. Considering the current burden of disease attributable to environmental factors and expansion in scope of applications of public health / environmental engineering science, it is essential to understand the present scenario of teaching, training and capacity building programs in these areas. Against this background the present research was carried out to know the current teaching and training programs in public health engineering and related disciplines in India and to understand the potential opportunities and challenges available. A systematic, predefined approach was used to collect and assemble the data related to various teaching and training programs in public health engineering / environmental engineering in India. Public health engineering / environmental engineering education and training in the country is mainly offered through engineering institutions, as pre-service and in-service training. Pre-service programs include diploma, degree (graduate) and post-graduate courses affiliated to various state technical boards, institutes and universities, whereas in-service training is mainly provided by Government of India recognized engineering and public health training institutes. Though trainees of these programs acquire skills related to engineering sciences, they significantly lack in public health skills. The teaching and training of public health engineering / environmental engineering is limited as a part of public health programs (MD Community Medicine, MPH, DPH) in India. There is need for developing teaching and training of public health engineering or environmental engineering as an interdisciplinary subject. Public health institutes can play an important and significant role in this

  16. Public health engineering education in India: Current scenario, opportunities and challenges

    Directory of Open Access Journals (Sweden)

    Mohammad Akhtar Hussain

    2011-01-01

    Full Text Available Public health engineering can play an important and significant role in solving environmental health issues. In order to confront public health challenges emerging out of environmental problems we need adequately trained public health engineers / environmental engineers. Considering the current burden of disease attributable to environmental factors and expansion in scope of applications of public health / environmental engineering science, it is essential to understand the present scenario of teaching, training and capacity building programs in these areas. Against this background the present research was carried out to know the current teaching and training programs in public health engineering and related disciplines in India and to understand the potential opportunities and challenges availables. A systematic, predefined approach was used to collect and assemble the data related to various teaching and training programs in public health engineering / environmental engineering in India. Public health engineering / environmental engineering education and training in the country is mainly offered through engineering institutions, as pre-service and in-service training. Pre-service programs include diploma, degree (graduate and post-graduate courses affiliated to various state technical boards, institutes and universities, whereas in-service training is mainly provided by Government of India recognized engineering and public health training institutes. Though trainees of these programs acquire skills related to engineering sciences, they significantly lack in public health skills. The teaching and training of public health engineering / environmental engineering is limited as a part of public health programs (MD Community Medicine, MPH, DPH in India. There is need for developing teaching and training of public health engineering or environmental engineering as an interdisciplinary subject. Public health institutes can play an important and

  17. Long-term survival and integration of transplanted engineered nervous tissue constructs promotes peripheral nerve regeneration.

    Science.gov (United States)

    Huang, Jason H; Cullen, D Kacy; Browne, Kevin D; Groff, Robert; Zhang, Jun; Pfister, Bryan J; Zager, Eric L; Smith, Douglas H

    2009-07-01

    Although peripheral nerve injury is a common consequence of trauma or surgery, there are insufficient means for repair. In particular, there is a critical need for improved methods to facilitate regeneration of axons across major nerve lesions. Here, we engineered transplantable living nervous tissue constructs to provide a labeled pathway to guide host axonal regeneration. These constructs consisted of stretch-grown, longitudinally aligned living axonal tracts inserted into poly(glycolic acid) tubes. The constructs (allogenic) were transplanted to bridge an excised segment of sciatic nerve in the rat, and histological analyses were performed at 6 and 16 weeks posttransplantation to determine graft survival, integration, and host regeneration. At both time points, the transplanted constructs were found to have maintained their pretransplant geometry, with surviving clusters of graft neuronal somata at the extremities of the constructs spanned by tracts of axons. Throughout the transplanted region, there was an intertwining plexus of host and graft axons, suggesting that the transplanted axons mediated host axonal regeneration across the lesion. By 16 weeks posttransplant, extensive myelination of axons was observed throughout the transplant region. Further, graft neurons had extended axons beyond the margins of the transplanted region, penetrating into the host nerve. Notably, this survival and integration of the allogenic constructs occurred in the absence of immunosuppression therapy. These findings demonstrate the promise of living tissue-engineered axonal constructs to bridge major nerve lesions and promote host regeneration, potentially by providing axon-mediated axonal outgrowth and guidance.

  18. Civil engineering project construction in the concrete construction technical analysis%土建施工中混凝土施工技术分析

    Institute of Scientific and Technical Information of China (English)

    谢超禄

    2014-01-01

    土建项目工程不同于其它项目工程的是,它涉及面广、专业多、工程复杂,在土建工程建设中,混凝土施工是被广泛应用的施工方式[1]。混凝土施工技术的好坏直接决定着土建工程项目质量。本文结合一线施工经验,对土建施工建设中的混凝土施工技术做出简要分析,以期待能够为一线土建混凝土有效施工提供参考。%Civil engineering is different from other projects,it is broad,more professional,engineering complex, in the construction of civil engineering,concrete construction is a widely used way of construction.Concrete construction technology is good or bad directly decides the quality of civil engineering projects.At this point,in this paper,the author combined with a line of construction experience,to make a brief analysis of civil engineering construction in the concrete construction technology,hoping to provide reference for civil engineering concrete construction.

  19. Facile fabrication of tissue-engineered constructs using nanopatterned cell sheets and magnetic levitation

    Science.gov (United States)

    Penland, Nisa; Choi, Eunpyo; Perla, Mikael; Park, Jungyul; Kim, Deok-Ho

    2017-02-01

    We report a simple and versatile method for in vitro fabrication of scaffold-free tissue-engineered constructs with predetermined cellular alignment, by combining magnetic cell levitation with thermoresponsive nanofabricated substratum (TNFS) based cell sheet engineering technique. The TNFS based nanotopography provides contact guidance cues for regulation of cellular alignment and enables cell sheet transfer, while magnetic nanoparticles facilitate the magnetic levitation of the cell sheet. The temperature-mediated change in surface wettability of the thermoresponsive poly(N-isopropylacrylamide), substratum enables the spontaneous detachment of cell monolayers, which can then be easily manipulated through use of a ring or disk shaped magnet. Our developed platform could be readily applicable to production of tissue-engineered constructs containing complex physiological structures for the study of tissue structure-function relationships, drug screening, and regenerative medicine.

  20. Segmentation Based Approach to Dynamic Page Construction from Search Engine Results

    CERN Document Server

    Kuppusamy, K S

    2012-01-01

    The results rendered by the search engines are mostly a linear snippet list. With the prolific increase in the dynamism of web pages there is a need for enhanced result lists from search engines in order to cope-up with the expectations of the users. This paper proposes a model for dynamic construction of a resultant page from various results fetched by the search engine, based on the web page segmentation approach. With the incorporation of personalization through user profile during the candidate segment selection, the enriched resultant page is constructed. The benefits of this approach include instant, one-shot navigation to relevant portions from various result items, in contrast to a linear page-by-page visit approach. The experiments conducted on the prototype model with various levels of users, quantifies the improvements in terms of amount of relevant information fetched.

  1. Facile fabrication of tissue-engineered constructs using nanopatterned cell sheets and magnetic levitation.

    Science.gov (United States)

    Penland, Nisa; Choi, Eunpyo; Perla, Mikael; Park, Jungyul; Kim, Deok-Ho

    2017-02-17

    We report a simple and versatile method for in vitro fabrication of scaffold-free tissue-engineered constructs with predetermined cellular alignment, by combining magnetic cell levitation with thermoresponsive nanofabricated substratum (TNFS) based cell sheet engineering technique. The TNFS based nanotopography provides contact guidance cues for regulation of cellular alignment and enables cell sheet transfer, while magnetic nanoparticles facilitate the magnetic levitation of the cell sheet. The temperature-mediated change in surface wettability of the thermoresponsive poly(N-isopropylacrylamide), substratum enables the spontaneous detachment of cell monolayers, which can then be easily manipulated through use of a ring or disk shaped magnet. Our developed platform could be readily applicable to production of tissue-engineered constructs containing complex physiological structures for the study of tissue structure-function relationships, drug screening, and regenerative medicine.

  2. Using Model Building in Structural Engineering to Enhance Understanding of Construction Principles and Methods

    Directory of Open Access Journals (Sweden)

    Niall Holmes

    2013-05-01

    Full Text Available This paper presents a new model building exercise in a second year module in the Department of Civil & Structural Engineering in the Dublin Institute of Technology (DIT. The activity aimed to improve students’ understanding of structural engineering, construction principles and methods. It allowed students to practically apply lecture material and construct a scaled model giving them an opportunity to study and visualise a real structure and generate their own ideas on how it should be assembled within a constructivist active learning environment. As a result, lectures were found to be more interactive and students more engaged in the discussions and provided a pathway to bridge the gap between theory (presented in lectures and the reality of their professions, which can aid them in their graduate careers. It is hoped that this type of active learning can be used in other engineering programmes to improve student understanding and as an opportunity to better apply lecture material to the real world.

  3. Segmentation Based Approach to Dynamic Page Construction from Search Engine Results

    Directory of Open Access Journals (Sweden)

    K.S. Kuppusamy,

    2011-03-01

    Full Text Available The results rendered by the search engines are mostly a linear snippet list. With the prolific increase in the dynamism of web pages there is a need for enhanced result lists from search engines inorder to cope-up with the expectations of the users. This paper proposes a model for dynamic construction of a resultant page from various results fetched by the search engine, based on the web pagesegmentation approach. With the incorporation of personalization through user profile during the candidate segment selection, the enriched resultant page is constructed. The benefits of this approachinclude instant, one-shot navigation to relevant portions from various result items, in contrast to a linear page-by-page visit approach. The experiments conducted on the prototype model with various levels of users, quantifies the improvements in terms of amount of relevant information fetched.

  4. Creation of a Large Adipose Tissue Construct in Humans Using a Tissue-engineering Chamber: A Step Forward in the Clinical Application of Soft Tissue Engineering.

    Science.gov (United States)

    Morrison, Wayne A; Marre, Diego; Grinsell, Damien; Batty, Andrew; Trost, Nicholas; O'Connor, Andrea J

    2016-04-01

    Tissue engineering is currently exploring new and exciting avenues for the repair of soft tissue and organ defects. Adipose tissue engineering using the tissue engineering chamber (TEC) model has yielded promising results in animals; however, to date, there have been no reports on the use of this device in humans. Five female post mastectomy patients ranging from 35 to 49years old were recruited and a pedicled thoracodorsal artery perforator fat flap ranging from 6 to 50ml was harvested, transposed onto the chest wall and covered by an acrylic perforated dome-shaped chamber ranging from 140 to 350cm(3). Magnetic resonance evaluation was performed at three and six months after chamber implantation. Chambers were removed at six months and samples were obtained for histological analysis. In one patient, newly formed tissue to a volume of 210ml was generated inside the chamber. One patient was unable to complete the trial and the other three failed to develop significant enlargement of the original fat flap, which, at the time of chamber explantation, was encased in a thick fibrous capsule. Our study provides evidence that generation of large well-vascularized tissue engineered constructs using the TEC is feasible in humans.

  5. A Data-Driven Approach to Reverse Engineering Customer Engagement Models: Towards Functional Constructs

    Science.gov (United States)

    de Vries, Natalie Jane; Carlson, Jamie; Moscato, Pablo

    2014-01-01

    Online consumer behavior in general and online customer engagement with brands in particular, has become a major focus of research activity fuelled by the exponential increase of interactive functions of the internet and social media platforms and applications. Current research in this area is mostly hypothesis-driven and much debate about the concept of Customer Engagement and its related constructs remains existent in the literature. In this paper, we aim to propose a novel methodology for reverse engineering a consumer behavior model for online customer engagement, based on a computational and data-driven perspective. This methodology could be generalized and prove useful for future research in the fields of consumer behaviors using questionnaire data or studies investigating other types of human behaviors. The method we propose contains five main stages; symbolic regression analysis, graph building, community detection, evaluation of results and finally, investigation of directed cycles and common feedback loops. The ‘communities’ of questionnaire items that emerge from our community detection method form possible ‘functional constructs’ inferred from data rather than assumed from literature and theory. Our results show consistent partitioning of questionnaire items into such ‘functional constructs’ suggesting the method proposed here could be adopted as a new data-driven way of human behavior modeling. PMID:25036766

  6. Osteochondral tissue engineering with biphasic scaffold: current strategies and techniques.

    Science.gov (United States)

    Shimomura, Kazunori; Moriguchi, Yu; Murawski, Christopher D; Yoshikawa, Hideki; Nakamura, Norimasa

    2014-10-01

    The management of osteoarthritis (OA) remains challenging and controversial. Although several clinical options exist for the treatment of OA, regeneration of the damaged articular cartilage has proved difficult due to the limited healing capacity. With the advancements in tissue engineering and cell-based technologies over the past decade, new therapeutic options for patients with osteochondral lesions potentially exist. This review will focus on the feasibility of tissue-engineered biphasic scaffolds, which can mimic the native osteochondral complex, for osteochondral repair and highlight the recent development of these techniques toward tissue regeneration. Moreover, basic anatomy, strategy for osteochondral repair, the design and fabrication methods of scaffolds, as well as the choice of cells, growth factor, and materials will be discussed. Specifically, we focus on the latest preclinical animal studies using large animals and clinical trials with high clinical relevance. In turn, this will facilitate an understanding of the latest trends in osteochondral repair and contribute to the future application of such clinical therapies in patients with OA.

  7. The design and construction of an electrohydrodynamic cartesian robot for the preparation of tissue engineering constructs.

    Science.gov (United States)

    Hashimdeen, Shaikh Hafeez; Miodownik, Mark; Edirisinghe, Mohan J

    2014-01-01

    In this work we bring together replicating rapid prototyping technology with electrohydrodynamic phenomena to develop a device with the ability to build structures in three-dimensions while simultaneously affording the user a degree of designing versatility and ease that is not seen in conventional computer numerically controlled machines. An attempt at reproducing an actual human ear using polycaprolactone was pursued to validate the hardware. Five different polycaprolactone solution concentrations between 7-15 wt% were used and printing was performed at applied voltages that ranged from 1 to 6 kV and at flow rates from 5 µl/min to 60 µl/min. The corresponding geometrical and aesthetic features of the printed constructs were studied to determine the effectiveness of the device. The 15 wt% concentration at 60 µl/min under an applied electric field of 6 kV was identified as the best operating parameters to work with.

  8. The Bank of Westminster and Hyland Park Construction Contracts as Engineering Student Classroom Projects; Construction Phase.

    Science.gov (United States)

    1984-12-13

    of the Bank of Westminster project as compared to other’projects. % * - ’ Laurence E. Reiner, Handbook for Construction Management (Englewood Cliffs...rA,,j II d~jI4 c OA, Pm M^,#fA T &,AO ’.\\&Jr~rS C-Act..PH0NE e..P L o j Loc 0/Z CALLeD Ree #, Lgsoi biw - Stio 0 F64Y 7A,.Xeb 7a Ao1-Pg*y PACAVAT.,oM...SUPPLIER REMARKS -5; I -1g 5 LIW -Q I Ph4CI- r1,0𔃺. PbADY 37 ~~R 48R*J -AAkD PfnRLJM% t,17rM 22T .8A7’ra1 IkAM Couc.. ~ bjw 5~~ ree 79.A.uw LifA

  9. Gene composer: database software for protein construct design, codon engineering, and gene synthesis.

    Science.gov (United States)

    Lorimer, Don; Raymond, Amy; Walchli, John; Mixon, Mark; Barrow, Adrienne; Wallace, Ellen; Grice, Rena; Burgin, Alex; Stewart, Lance

    2009-04-21

    To improve efficiency in high throughput protein structure determination, we have developed a database software package, Gene Composer, which facilitates the information-rich design of protein constructs and their codon engineered synthetic gene sequences. With its modular workflow design and numerous graphical user interfaces, Gene Composer enables researchers to perform all common bio-informatics steps used in modern structure guided protein engineering and synthetic gene engineering. An interactive Alignment Viewer allows the researcher to simultaneously visualize sequence conservation in the context of known protein secondary structure, ligand contacts, water contacts, crystal contacts, B-factors, solvent accessible area, residue property type and several other useful property views. The Construct Design Module enables the facile design of novel protein constructs with altered N- and C-termini, internal insertions or deletions, point mutations, and desired affinity tags. The modifications can be combined and permuted into multiple protein constructs, and then virtually cloned in silico into defined expression vectors. The Gene Design Module uses a protein-to-gene algorithm that automates the back-translation of a protein amino acid sequence into a codon engineered nucleic acid gene sequence according to a selected codon usage table with minimal codon usage threshold, defined G:C% content, and desired sequence features achieved through synonymous codon selection that is optimized for the intended expression system. The gene-to-oligo algorithm of the Gene Design Module plans out all of the required overlapping oligonucleotides and mutagenic primers needed to synthesize the desired gene constructs by PCR, and for physically cloning them into selected vectors by the most popular subcloning strategies. We present a complete description of Gene Composer functionality, and an efficient PCR-based synthetic gene assembly procedure with mis-match specific endonuclease

  10. Gene Composer: database software for protein construct design, codon engineering, and gene synthesis

    Directory of Open Access Journals (Sweden)

    Mixon Mark

    2009-04-01

    Full Text Available Abstract Background To improve efficiency in high throughput protein structure determination, we have developed a database software package, Gene Composer, which facilitates the information-rich design of protein constructs and their codon engineered synthetic gene sequences. With its modular workflow design and numerous graphical user interfaces, Gene Composer enables researchers to perform all common bio-informatics steps used in modern structure guided protein engineering and synthetic gene engineering. Results An interactive Alignment Viewer allows the researcher to simultaneously visualize sequence conservation in the context of known protein secondary structure, ligand contacts, water contacts, crystal contacts, B-factors, solvent accessible area, residue property type and several other useful property views. The Construct Design Module enables the facile design of novel protein constructs with altered N- and C-termini, internal insertions or deletions, point mutations, and desired affinity tags. The modifications can be combined and permuted into multiple protein constructs, and then virtually cloned in silico into defined expression vectors. The Gene Design Module uses a protein-to-gene algorithm that automates the back-translation of a protein amino acid sequence into a codon engineered nucleic acid gene sequence according to a selected codon usage table with minimal codon usage threshold, defined G:C% content, and desired sequence features achieved through synonymous codon selection that is optimized for the intended expression system. The gene-to-oligo algorithm of the Gene Design Module plans out all of the required overlapping oligonucleotides and mutagenic primers needed to synthesize the desired gene constructs by PCR, and for physically cloning them into selected vectors by the most popular subcloning strategies. Conclusion We present a complete description of Gene Composer functionality, and an efficient PCR-based synthetic gene

  11. Sustainable Construction for Urban Infill Development Using Engineered Massive Wood Panel Systems

    Directory of Open Access Journals (Sweden)

    Steffen Lehmann

    2012-10-01

    Full Text Available Prefabricated engineered solid wood panel construction systems can sequester and store CO2. Modular cross-laminated timber (CLT, also called cross-lam panels form the basis of low-carbon, engineered construction systems using solid wood panels that can be used to build residential infill developments of 10 storeys or higher. Multi-apartment buildings of 4 to 10 storeys constructed entirely in timber, such as recently in Europe, are innovative, but their social and cultural acceptance in Australia and North America is at this stage still uncertain. Future commercial utilisation is only possible if there is a user acceptance. The author is part of a research team that aims to study two problems: first models of urban infill; then focus on how the use of the CLT systems can play an important role in facilitating a more livable city with better models of infill housing. Wood is an important contemporary building resource due to its low embodied energy and unique attributes. The potential of prefabricated engineered solid wood panel systems, such as CLT, as a sustainable building material and system is only just being realised around the globe. Since timber is one of the few materials that has the capacity to store carbon in large quantities over a long period of time, solid wood panel construction offers the opportunity of carbon engineering, to turn buildings into ‘carbon sinks’. Thus some of the historically negative environmental impact of urban development and construction can be turned around with CLT construction on brownfield sites.

  12. Rapid prototyping for biomedical engineering: current capabilities and challenges.

    Science.gov (United States)

    Lantada, Andrés Díaz; Morgado, Pilar Lafont

    2012-01-01

    A new set of manufacturing technologies has emerged in the past decades to address market requirements in a customized way and to provide support for research tasks that require prototypes. These new techniques and technologies are usually referred to as rapid prototyping and manufacturing technologies, and they allow prototypes to be produced in a wide range of materials with remarkable precision in a couple of hours. Although they have been rapidly incorporated into product development methodologies, they are still under development, and their applications in bioengineering are continuously evolving. Rapid prototyping and manufacturing technologies can be of assistance in every stage of the development process of novel biodevices, to address various problems that can arise in the devices' interactions with biological systems and the fact that the design decisions must be tested carefully. This review focuses on the main fields of application for rapid prototyping in biomedical engineering and health sciences, as well as on the most remarkable challenges and research trends.

  13. Study on the technology for highway construction and engineering practices in permafrost regions

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In order to systemically summarize and integrate technology of highway construction in permafrost regions on the Qinghai-Tibet Plateau,we studied disciplines and mechanisms of formation and development of problems and challenges in highway engineer-ing in high-altitude permafrost regions based on construction experiences for 50 years and on 30 years of research regarding the Qinghai-Tibet and Xikang highways.Embankments,pavements,bridges,and countermeasures for ecosystem protection in per-mafrost regions were the main study objects.We combined extensive analysis of key problems of engineering stability with inter-action between permafrost and highways,theoretical models,indoor tests,and field tests to reveal the interaction between em-bankments,pavements,bridge piles,and permafrost.In this paper,we propose a series of engineering measures for highway sta-bility,design parameters,key indexes for pavement durability in low temperature,relationships between re-freezing time of bridge-pile foundation and strength development as well as ecosystem recovery in high-latitude cold regions;these eventually form a construction technology package for permafrost regions.

  14. Morphological and functional characteristics of three-dimensional engineered bone-ligament-bone constructs following implantation.

    Science.gov (United States)

    Ma, Jinjin; Goble, Kristen; Smietana, Michael; Kostrominova, Tatiana; Larkin, Lisa; Arruda, Ellen M

    2009-10-01

    The incidence of ligament injury has recently been estimated at 400,000/year. The preferred treatment is reconstruction using an allograft, but outcomes are limited by donor availability, biomechanical incompatibility, and immune rejection. The creation of an engineered ligament in vitro solely from patient bone marrow stromal cells (has the potential to greatly enhance outcomes in knee reconstructions. Our laboratory has developed a scaffoldless method to engineer three-dimensional (3D) ligament and bone constructs from rat bone marrow stem cells in vitro. Coculture of these two engineered constructs results in a 3D bone-ligament-bone (BLB) construct with viable entheses, which was successfully used for medial collateral ligament (MCL) replacement in a rat model. 1 month and 2 month implantations were applied to the engineered BLBs. Implantation of 3D BLBs in a MCL replacement application demonstrated that our in vitro engineered tissues grew and remodeled quickly in vivo to an advanced phenotype and partially restored function of the knee. The explanted 3D BLB ligament region stained positively for type I collagen and elastin and was well vascularized after 1 and 2 months in vivo. Tangent moduli of the ligament portion of the 3D BLB 1 month explants increased by a factor of 2.4 over in vitro controls, to a value equivalent to those observed in 14-day-old neonatal rat MCLs. The 3D BLB 1 month explants also exhibited a functionally graded response that closely matched native MCL inhomogeneity, indicating the constructs functionally adapted in vivo.

  15. Raman fiberoptic probe for monitoring human tissue engineered oral mucosa constructs

    Science.gov (United States)

    Khmaladze, Alexander; Kuo, Shiuhyang; Okagbare, Paul; Marcelo, Cynthia L.; Feinberg, Stephen E.; Morris, Michael D.

    2013-02-01

    In oral and maxillofacial surgery, there is a need for tissue engineered constructs for dental implants, reconstructions due to trauma, oral cancer or congenital defects. A non-invasive quality monitoring of the fabrication of tissue engineered constructs during their production and implantation is a required component of any successful tissue engineering technique. We demonstrate the design and application of a Raman spectroscopic probe for rapid and noninvasive monitoring of Ex Vivo Produced Oral Mucosa Equivalent constructs (EVPOMEs). We conducted in vivo studies to identify Raman spectroscopic failure indicators for EVPOMEs (already developed in vitro), and found that Raman spectra of EVPOMEs exposed to thermal stress showed correlation of the band height ratio of CH2 deformation to phenylalanine ring breathing modes, providing a Raman metric to distinguish between viable and nonviable constructs. This is the first step towards the ultimate goal to design a stand-alone system, which will be usable in a clinical setting, as the data processing and analysis will be performed with minimal user intervention, based on already established and tested Raman spectroscopic indicators for EVPOMEs.

  16. Human oral mucosa tissue-engineered constructs monitored by Raman fiber-optic probe.

    Science.gov (United States)

    Khmaladze, Alexander; Kuo, Shiuhyang; Kim, Roderick Y; Matthews, Robert V; Marcelo, Cynthia L; Feinberg, Stephen E; Morris, Michael D

    2015-01-01

    In maxillofacial and oral surgery, there is a need for the development of tissue-engineered constructs. They are used for reconstructions due to trauma, dental implants, congenital defects, or oral cancer. A noninvasive monitoring of the fabrication of tissue-engineered constructs at the production and implantation stages done in real time is extremely important for predicting the success of tissue-engineered grafts. We demonstrated a Raman spectroscopic probe system, its design and application, for real-time ex vivo produced oral mucosa equivalent (EVPOME) constructs noninvasive monitoring. We performed in vivo studies to find Raman spectroscopic indicators for postimplanted EVPOME failure and determined that Raman spectra of EVPOMEs preexposed to thermal stress during manufacturing procedures displayed correlation of the band height ratio of CH2 deformation to phenylalanine ring breathing modes, giving a Raman metric to distinguish between healthy and compromised postimplanted constructs. This study is the step toward our ultimate goal to develop a stand-alone system, to be used in a clinical setting, where the data collection and analysis are conducted on the basis of these spectroscopic indicators with minimal user intervention.

  17. Constructing a core framework of visual engine for Digital Earth system

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A visual engine is the core of a Digital Earth system.There is a wide variety of functional requirements in Digital Earth system and different requirements correspond to different operations.Based on the development of the visual engine for ChinaStar,a 3D Digital China prototype software platform,and analysis of 3D Digital Earth platforms such as Google Earth,Virtual Earth,Skyline,etc,are discussed.A common core framework for a visual engine is proposed in this paper to construct a visual engine and then with this framework various Digital Earth application systems can be developed efficient.The parametric model of the Earth,scheduling and optimization in visual field,choice of 3D graphics library,and designing component-based visual engine framework of Digital Earth are discussed in detail.In addition,the relationships among these four basic components and the construction of visualization applications of Digital Earth by this method are also discussed.

  18. Justification of application of new types of fastening of slopes of hydraulic engineering constructions

    Directory of Open Access Journals (Sweden)

    Smyvalov Anatoly

    2017-01-01

    Full Text Available The article represents the analysis of various types of fastenings of the soil slopes which have found broad application in the hydrotechnical construction practice for the last 10-15 years. It is noted that, generally, new types of fastenings represent composite materials made of concrete, metal and polymers. Experience shows that producers of the construction materials used in bank protection designs seek to recommend them for the solution of a wide range of tasks, at the same time it isn’t always founded. The authors, on the basis of the analysis of experience with the types of fastenings and also modern domestic and foreign recommendations about their design and construction, offer a technique of justification of new types of fastenings of slopes of hydraulic engineering constructions. The use of concrete filled geotextile mats in bank protection is brought out as a practical realization of the represented technique.

  19. Structure and Functional Evaluation of Tendon–Skeletal Muscle Constructs Engineered in Vitro

    Science.gov (United States)

    LARKIN, LISA M.; CALVE, SARAH; KOSTROMINOVA, TATIANA Y.; ARRUDA, ELLEN M.

    2009-01-01

    During muscle contraction, the integrity of the myotendinous junction (MTJ) is important for the transmission of force from muscle to tendon. We evaluated the contractile and structural characteristics of 3-dimensional (3-D) skeletal muscle constructs co-cultured with engineered self-organized tendon constructs (n = 4), or segments of adult (n = 4) or fetal (n = 5) rat-tail tendon. We hypothesized that the co-culture of tendon and muscle would produce constructs with viable muscle–tendon interfaces that remain intact during generation of force. Construct diameter (μm) and maximum isometric force (μN) were measured, and specific force (kPa) was determined. After measure of force, constructs were loaded at a constant strain rate until failure and surface strains were recorded optically across the tendon, the muscle and the interface and used to determine the tangent modulus (passive stiffness) of the construct. Frozen samples were used for Trichrome Masson staining and immunofluorescent analysis of the MTJ-specific protein paxillin. No differences were observed between the groups with respect to diameter, maximum force, or specific force. The MTJ was robust and withstood tensile loading beyond the physiological strain range. The majority of the constructs failed in the muscle region. At the MTJ, there is an increase in the expression and localization of paxillin. In conclusion, using 3 sources of tendon tissue, we successfully engineered 3-D muscle–tendon constructs with functionally viable MTJ, characterized by structural features and protein expression patterns resembling neonatal MTJs in vivo. PMID:17518629

  20. Engineering

    National Research Council Canada - National Science Library

    Includes papers in the following fields: Aerospace Engineering, Agricultural Engineering, Chemical Engineering, Civil Engineering, Electrical Engineering, Environmental Engineering, Industrial Engineering, Materials Engineering, Mechanical...

  1. Cardiac tissue engineering: cell seeding, cultivation parameters, and tissue construct characterization.

    Science.gov (United States)

    Carrier, R L; Papadaki, M; Rupnick, M; Schoen, F J; Bursac, N; Langer, R; Freed, L E; Vunjak-Novakovic, G

    1999-09-01

    Cardiac tissue engineering has been motivated by the need to create functional tissue equivalents for scientific studies and cardiac tissue repair. We previously demonstrated that contractile cardiac cell-polymer constructs can be cultivated using isolated cells, 3-dimensional scaffolds, and bioreactors. In the present work, we examined the effects of (1) cell source (neonatal rat or embryonic chick), (2) initial cell seeding density, (3) cell seeding vessel, and (4) tissue culture vessel on the structure and composition of engineered cardiac muscle. Constructs seeded under well-mixed conditions with rat heart cells at a high initial density ((6-8) x 10(6) cells/polymer scaffold) maintained structural integrity and contained macroscopic contractile areas (approximately 20 mm(2)). Seeding in rotating vessels (laminar flow) rather than mixed flasks (turbulent flow) resulted in 23% higher seeding efficiency and 20% less cell damage as assessed by medium lactate dehydrogenase levels (p laminar and dynamic, yielded constructs with a more active, aerobic metabolism as compared to constructs cultured in mixed or static flasks. After 1-2 weeks of cultivation, tissue constructs expressed cardiac specific proteins and ultrastructural features and had approximately 2-6 times lower cellularity (p < 0.05) but similar metabolic activity per unit cell when compared to native cardiac tissue.

  2. The development of the collagen fibre network in tissue-engineered cartilage constructs in vivo. Engineered cartilage reorganises fibre network

    Directory of Open Access Journals (Sweden)

    H Paetzold

    2012-04-01

    Full Text Available For long term durability of tissue-engineered cartilage implanted in vivo, the development of the collagen fibre network orientation is essential as well as the distribution of collagen, since expanded chondrocytes are known to synthesise collagen type I. Typically, these properties differ strongly between native and tissue-engineered cartilage. Nonetheless, the clinical results of a pilot study with implanted tissue-engineered cartilage in pigs were surprisingly good. The purpose of this study was therefore to analyse if the structure and composition of the artificial cartilage tissue changes in the first 52 weeks after implantation. Thus, collagen network orientation and collagen type distribution in tissue-engineered cartilage-carrier-constructs implanted in the knee joints of Göttinger minipigs for 2, 26 or 52 weeks have been further investigated by processing digitised microscopy images of histological sections. The comparison to native cartilage demonstrated that fibre orientation over the cartilage depth has a clear tendency towards native cartilage with increasing time of implantation. After 2 weeks, the collagen fibres of the superficial zone were oriented parallel to the articular surface with little anisotropy present in the middle and deep zones. Overall, fibre orientation and collagen distribution within the implants were less homogenous than in native cartilage tissue. Despite a relatively low number of specimens, the consistent observation of a continuous approximation to native tissue is very promising and suggests that it may not be necessary to engineer the perfect tissue for implantation but rather to provide an intermediate solution to help the body to heal itself.

  3. EARTH’S CRUST FRACTURES AND THEIR INFLUENCE ON CONSTRUCTION AND OPERATION OF ENGINEERING STRUCTURES

    Directory of Open Access Journals (Sweden)

    V. I. Mikhailov

    2009-01-01

    Full Text Available The paper considers a tectonics influence on construction and operation of engineering structures on the territory of Belarus.  An example of studying  tectonic  fracture zones  in  the  Soligorsk  mining region with disturbed geological medium is given in the paper. The paper contains conclusions on necessity of obligatory account of geo-dynamic factors at all stages of constructing industrial projects, pipe-line transport and automobile roads.

  4. Barriers to the Uptake of Concurrent Engineering in the Nigerian Construction Industry

    Directory of Open Access Journals (Sweden)

    Nathaniel Anny Aniekwu

    2012-12-01

    engineering and also to compute the Kendall’s coefficient of concordance, which assess the levels of agreement among the judges on the consistency of the rankings. A Kendall’s coefficient of concordance of W=0.57365 was recorded. A lack of awareness emerged as the most important barrier against the integration of this concept into the Nigerian construction industry. The top five variables are all human factors that can be ameliorated by proper education.

  5. Developing remanufacturing engineering, constructing cycle economy and building saving-oriented society

    Institute of Scientific and Technical Information of China (English)

    XU Bin-shi; LIU Shi-can; WANG Hai-dou

    2005-01-01

    In the course of creating immense wealth, manufacturing industry has excessively consumed the re sources and energy in the earth, and seriously polluted the environment. To take progress as the sustainable development way, save resource and improve environment, our nation has been advocating to construct the cycle economy and saving-oriented society. Taking the remanufacturing engineering as the representative, the "4R" rule (Reduce,Reuse, Recycle and Remanufacture) is the important measure to get the goal. Remanufacturing engineering is the industrialization of high-tech maintenance of the waste and worn productions, and is one of the most active factors in "4R". The development of high and new technology takes the important effect to promote the remanufacturing engineering.

  6. Study on the technology for highway construction and engineering practices in permafrost regions

    Institute of Scientific and Technical Information of China (English)

    ShuangJie Wang; JianBing Chen; JiLin Qi

    2009-01-01

    In order to systemically summarize and integrate technology of highway construction in permafrost regions on the Qinghai-Tibet Plateau, we studied disciplines and mechanisms of formation and development of problems and challenges in highway engineering in high-altitude permafrost regions based on construction experiences for 50 years and on 30 years of research regarding the Qinghai-Tibet and Xikang highways. Embankments, pavements, bridges, and countermeasures for ecosystem protection in permafrost regions were the main study objects. We combined extensive analysis of key problems of engineering stability with interaction between permafrost and highways, theoretical models, indoor tests, and field tests to reveal the interaction between embankments, pavements, bridge piles, and permafrost. In this paper, we propose a series of engineering measures for highway stability, design parameters, key indexes for pavement durability in low temperature, relationships between re-freezing time of bridge-pile foundation and strength development as well as ecosystem recovery in high-latitude cold regions; these eventually form a construction technology package for permafrost regions.

  7. Modelling counter-current chromatography: a chemical engineering perspective.

    Science.gov (United States)

    Kostanian, A E

    2002-10-11

    In conventional chromatography, a solute is usually viewed to be longitudinally transported only in the mobile phase, remaining longitudinally motionless in the stationary phase. In counter-current chromatography, both phases undergo intense mixing in the variable force field of a coil planet centrifuge and longitudinal dispersion of matter in the stationary phase is not to be excluded. To take into account longitudinal mixing in both phases, a cell model of chromatographic process is proposed in which the number of perfectly mixed cells n is determined by the rates of mixing in stationary (Ds) and mobile (Dm) phases by the equation n = LF/(2ADc)/(1 + Sf(lambda - 1)) with A = K(D)D(S)/Dm (F, L, Ac and KD are the mobile phase flow-rate, column length, column cross-section and distribution ratio, respectively). This equation has been derived by comparing the discontinuous cell model with continuous diffusion assuming equilibrium conditions. Parameter determination and their relationships are discussed.

  8. 浅析建筑工程机电的安装施工技术%Analysis of the Installation Construction Technology of Construction Engineering Machine Electricity

    Institute of Scientific and Technical Information of China (English)

    马瑞琴

    2013-01-01

    机电安装工程是建筑工程的重要组成部分,随着人们对建筑的要求越来越高,机电安装工程也受到人们的普遍关注。本文结合实例,对建筑工程机电的安装施工技术进行了分析。%The mechanical and electrical instal ation enginee-ring is an important part of construction engineering. As peop-le have increasingly demand to the architectural, the mechanic-al and electrical instal ation engineering has also been wides-pread concerned. In this article, the author bases on the insta-nce and analyzes the instal ation construction technology of c-onstruction engineering mechanical and electrical.

  9. Spatial Engineering of Osteochondral Tissue Constructs Through Microfluidically Directed Differentiation of Mesenchymal Stem Cells.

    Science.gov (United States)

    Goldman, Stephen M; Barabino, Gilda A

    2016-01-01

    The development of tissue engineered osteochondral units has been slowed by a number of technical hurdles associated with recapitulating their heterogeneous nature ex vivo. Subsequently, numerous approaches with respect to cell sourcing, scaffolding composition, and culture media formulation have been pursued, which have led to high variability in outcomes and ultimately the lack of a consensus bioprocessing strategy. As such, the objective of this study was to standardize the design process by focusing on differentially supporting formation of cartilaginous and bony matrix by a single cell source in a spatially controlled manner within a single material system. A cell-polymer solution of bovine mesenchymal stem cells and agarose was cast against micromolds of a serpentine network and stacked to produce tissue constructs containing two independent microfluidic networks. Constructs were fluidically connected to two controlled flow loops and supplied with independently tuned differentiation parameters for chondrogenic and osteogenic induction, respectively. Constructs receiving inductive media showed differential gene expression of both chondrogenic and osteogenic markers in opposite directions along the thickness of the construct that was recapitulated at the protein level with respect to collagens I, II, and X. A control group receiving noninductive media showed homogeneous expression of these biomarkers measured in lower concentrations at both the mRNA and protein level. This work represents an important step in the rational design of engineered osteochondral units through establishment of an enabling technology for further optimization of scaffolding formulations and bioprocessing conditions toward the production of commercially viable osteochondral tissue products.

  10. Design and Validation of Equiaxial Mechanical Strain Platform, EQUicycler, for 3D Tissue Engineered Constructs.

    Science.gov (United States)

    Elsaadany, Mostafa; Harris, Matthew; Yildirim-Ayan, Eda

    2017-01-01

    It is crucial to replicate the micromechanical milieu of native tissues to achieve efficacious tissue engineering and regenerative therapy. In this study, we introduced an innovative loading platform, EQUicycler, that utilizes a simple, yet effective, and well-controlled mechanism to apply physiologically relevant homogenous mechanical equiaxial strain on three-dimensional cell-embedded tissue scaffolds. The design of EQUicycler ensured elimination of gripping effects through the use of biologically compatible silicone posts for direct transfer of the mechanical load to the scaffolds. Finite Element Modeling (FEM) was created to understand and to quantify how much applied global strain was transferred from the loading mechanism to the tissue constructs. In vitro studies were conducted on various cell lines associated with tissues exposed to equiaxial mechanical loading in their native environment. In vitro results demonstrated that EQUicycler was effective in maintaining and promoting the viability of different musculoskeletal cell lines and upregulating early differentiation of osteoprogenitor cells. By utilizing EQUicycler, collagen fibers of the constructs were actively remodeled. Residing cells within the collagen construct elongated and aligned with strain direction upon mechanical loading. EQUicycler can provide an efficient and cost-effective tool to conduct mechanistic studies for tissue engineered constructs designed for tissue systems under mechanical loading in vivo.

  11. Rapid prototyping of tissue-engineering constructs, using photopolymerizable hydrogels and stereolithography.

    Science.gov (United States)

    Dhariwala, Busaina; Hunt, Elaine; Boland, Thomas

    2004-01-01

    One of the most important aspects of tissue engineering is the design of the scaffold providing the mechanical strength and access to nutrients for the new tissue. For customized tissue engineering, it is essential to be able to fabricate three-dimensional scaffolds of various geometric shapes, in order to repair defects caused by accidents, surgery, or birth. Rapid prototyping or solid free-form fabrication (SFF) techniques hold great promise for designing three-dimensional customized scaffolds, yet traditional cell-seeding techniques may not provide enough cell mass for larger constructs. This article presents a novel attempt to fabricate three-dimensional scaffolds, using hydrogels combined with cell encapsulation to fabricate high-density tissue constructs. A commercially available stereolithography technique was applied to fabricate scaffolds using poly(ethylene oxide) and poly(ethylene glycol)dimethacrylate photopolymerizable hydrogels. Mechanical characterization shows the constructs to be comparable with soft tissues in terms of elasticity. High cell viability was achieved and high-density constructs fabricated.

  12. CURRENT VECTOR CONTROL OF PERMANENT-MAGNET SYNCHRONOUS MOTOR OF HYBRID VEHICLE ENGINE

    Directory of Open Access Journals (Sweden)

    S. Serikov

    2009-01-01

    Full Text Available Characteristics of traction permanent-magnet synchronous motor under current vector optimum control in the possible traction-speed mode area which are relevant for hybrid vehicle engine have been investigated. As a criterion of optimality a maximum of electromagnetic moment per unit of current have been taken.

  13. Novel method to improve vascularization of tissue engineered constructs with biodegradable fibers.

    Science.gov (United States)

    Wong, Hui Kian; Ivan Lam, Chee Ren; Wen, Feng; Mark Chong, Seow Khoon; Tan, Nguan Soon; Jerry, Chan; Pal, Mintu; Tan, Lay Poh

    2016-01-07

    Tissue engineered grafts lack adequate vascularization and suffer from poor perfusion in vivo curtailing clinical application. Improving vascularization in any tissue implants would hence increase their survivability and treatment efficacy. Many prevascularization strategies established to date involves the angiogenic induction of endothelial progenitor cells in thick tissue engineered scaffolds to obtain vascularization. These 3D scaffolds typically require a dynamic cell culturing system involving/needful of bioreactors to obtain vascularization in thick tissue engineered scaffolds. Herein, we developed a novel method to engineer a vessel network without bioreactor, where 3D blood vessels could be simply obtained in a 2D static cell culturing system. This network could be used to augment the prevascularization of tissue engineered grafts. Endothelial cells (HUVECs) were confluently cultured on resorbable electrospun poly (D, L-lactide-co-glycolide) microfibers of capillary dimensions. These cell encapsulated capillary fibers were further embedded in collagen with HUVECs and vascular endothelial growth factor. Green fluorescent protein and red fluorescent protein expressing HUVECs were used to label cells on fiber and in collagen respectively for visualization and monitoring of capillary network formation. Seeded HUVECs in the hybrid construct were subsequently cultured for 30 days before implantation. Vessel density was measured by the total tubule length per unit area at different time points. In vitro results indicated that the fibers provide contact guidance to form primary networks to direct more vessels branching of HUVECs in hybrid constructs and the vessel integrity of microvasculature was retained after fiber degradation. In addition, these preformed engineered capillaries could capably inosculate with de novo capillaries in collagen when combined, giving rise to a hybrid pre-vascularized scaffold of more extensive vessel network and interconnections

  14. Repair of acutely injured spinal cord through constructing tissue-engineered neural complex in adult rats

    Institute of Scientific and Technical Information of China (English)

    PU Yu; GUO Qing-shan; WANG Ai-min; WU Si-yu; XING Shu-xing; ZHANG Zhong-rong

    2007-01-01

    Objective: To construct tissue-engineered neural complex in vitro and study its effect in repairing acutely injured spinal cord in adult rats. Methods: Neural stem cells were harvested from the spinal cord of embryo rats and propagated in vitro. Then the neural stem cells were seeded into polyglycolic acid scaffolds and co-cultured with extract of embryonic spinal cord in vitro. Immunofluorescence histochemistry and scanning electron microscope were used to observe the microstructure of this complex. Animal model of spine semi-transection was made and tissue-engineered neural complex was implanted by surgical intervention. Six weeks after transplantation, functional evaluation and histochemistry were applied to evaluate the functional recovery and anatomic reconstruction. Results: The tissue-engineered neural complex had a distinct structure, which contained neonatal neurons, oligodendrocytes and astrocytes. After tissue-engineered neural complex was implanted into the injured spinal cord, the cell components such as neurons, astrocytes and oligodendrocytes, could survive and keep on developing. The adult rats suffering from spinal cord injury got an obvious neurological recovery in motor skills. Conclusions: The tissue-engineered neural complex appears to have therapeutic effects on the functional recovery and anatomic reconstruction of the adult rats with spinal cord injury.

  15. Current State of Off-Site Manufacturing in Australian and Chinese Residential Construction

    Directory of Open Access Journals (Sweden)

    Malik M. A. Khalfan

    2014-01-01

    Full Text Available Many techniques have been implemented to make construction industry more productive. The key focus is on reduction of total duration, reduction in construction cost, improvements in the quality, achieving more sustainable development, and safer construction sites. One of the techniques, which is emerging in the last two decades, is the use of off-site manufacturing (OSM within the construction industry. Several research projects and industry initiatives have reported the benefits and challenges of implementation of OSM. The focus of this paper is Australian and Chinese residential construction industry and the uptake of the OSM concepts. The paper presents a brief review of the current state of OSM in the last five to seven years with the context of the above-mentioned two countries. The paper concludes that the construction industry, both in Australia and China, needs to start walking the talk with regard to OSM adoption. The paper also highlights some of the research gaps in the OSM area, especially within the housing and residential sector.

  16. A revisit on the current practice of dispute resolution and ADR in the Malaysian construction industry

    Directory of Open Access Journals (Sweden)

    Mohd Suhaimi Mohd Danuri

    2012-06-01

    Full Text Available The current dispute resolution procedures available in the Malaysian construction industry are mainly litigation and arbitration. In addition, the alternative dispute resolutions (ADR, namely mediation and adjudication, have also been introduced as the other methods for resolving disputes. The objective of this study is to examine the current practice of dispute resolution and ADR available in the Malaysian construction industry. The aim of this paper is two-fold: to report the current practice of dispute resolution and ADR, and identify the attributes of successful implementation of both mechanisms based on the perceptions of the Malaysian construction industry players. From the jurisprudence point of view, this study looks into the law as it is, in relation to the current practice of dispute resolution and ADR, by showing how those findings can be used to explain why improvement is needed to promote a successful and well received dispute resolution and ADR, and what lessons can be learnt, towards the formulation of a more viable methods for the Malaysian construction industry. NVivo software has been used to manage and organise the complete interview transcripts and facilitate the data analysis process for this study. Literature review reveals a continuous development of dispute resolution and ADR in the Malaysian construction industry, while, globally the industry has not only embraced ADR but also spearheaded the development of innovative forms of dispute avoidance mechanism. The findings of interviews show that locally, apart from litigation, the common types of ADR are arbitration, mediation and ad hoc mechanism. The findings also lead to the discovery of the following attributes: faster, less procedural, cost effective and enforceable; regulation and government's support; professionalism and ethic; training; and facility, that may promote a successful implementation of dispute resolution and ADR in Malaysia.

  17. The interplay between tissue growth and scaffold degradation in engineered tissue constructs

    KAUST Repository

    O’Dea, R. D.

    2012-09-18

    In vitro tissue engineering is emerging as a potential tool to meet the high demand for replacement tissue, caused by the increased incidence of tissue degeneration and damage. A key challenge in this field is ensuring that the mechanical properties of the engineered tissue are appropriate for the in vivo environment. Achieving this goal will require detailed understanding of the interplay between cell proliferation, extracellular matrix (ECM) deposition and scaffold degradation. In this paper, we use a mathematical model (based upon a multiphase continuum framework) to investigate the interplay between tissue growth and scaffold degradation during tissue construct evolution in vitro. Our model accommodates a cell population and culture medium, modelled as viscous fluids, together with a porous scaffold and ECM deposited by the cells, represented as rigid porous materials. We focus on tissue growth within a perfusion bioreactor system, and investigate how the predicted tissue composition is altered under the influence of (1) differential interactions between cells and the supporting scaffold and their associated ECM, (2) scaffold degradation, and (3) mechanotransduction-regulated cell proliferation and ECM deposition. Numerical simulation of the model equations reveals that scaffold heterogeneity typical of that obtained from μCT scans of tissue engineering scaffolds can lead to significant variation in the flow-induced mechanical stimuli experienced by cells seeded in the scaffold. This leads to strong heterogeneity in the deposition of ECM. Furthermore, preferential adherence of cells to the ECM in favour of the artificial scaffold appears to have no significant influence on the eventual construct composition; adherence of cells to these supporting structures does, however, lead to cell and ECM distributions which mimic and exaggerate the heterogeneity of the underlying scaffold. Such phenomena have important ramifications for the mechanical integrity of

  18. Engineering and construction projects for oil and gas processing facilities: Contracting, uncertainty and the economics of information

    Energy Technology Data Exchange (ETDEWEB)

    Berends, Kees [Capital Contracting Services, Shell Global Solutions International B.V., The Hague (Netherlands)

    2007-08-15

    The amount of oil and gas processing capacity required to meet demand during the next 20 years is more than twice the amount realised during the last decades. Engineering and Construction contractors (ECs) play a key role in the development and implementation of Large Engineering and Construction Projects (LECPs) for these facilities. We examine the characteristics of LECPs, demand and supply of the contracting market and the strategies traditionally adopted by owners to contract out the development and implementation of these projects to ECs. We demonstrate that these traditional strategies are not longer effective, in the current 'sellers market', to mitigate the oligopolistic economic inefficiencies. As the 'overheating' of the contracting market is expected to continue for a considerable period of time, alternative contracting strategies are required. Contract theory, particularly the economics of information on LECPs, indicates how alternative contracting strategies can be used to overcome economic inefficiencies. The effective use of these alternative strategies requires increased owner involvement and their effectiveness is contingent upon owner competency and ECs acting as the owner's agent rather than its adversary. This will require an organisational and behavioural change process for both owners and ECs. (author)

  19. Engineering Ethics Education : Its Necessity, Objectives, Methods, Current State, and Challenges

    Science.gov (United States)

    Fudano, Jun

    The importance of engineering ethics education has become widely recognized in the industrialized countries including Japan. This paper examines the background against which engineering ethics education is required, and reviews its objectives, methods, and challenges, as well as its current state. In pointing out important issues associated with the apparent acceptance and quantitative development of ethics education, especially after the establishment of the Japan Accreditation Board for Engineering Education in 1999, the author stresses that the most serious problem is the lack of common understanding on the objectives of engineering ethics education. As a strategy to improve the situation, the so-called “Ethics-across-the-Curriculum” approach is introduced. The author also claims that business/organization ethics which is consistent with engineering ethics should be promoted in Japan.

  20. Pile Foundation Construction Technology of Modern Construction Engineering%浅析现代建筑工程桩基工程施工技术

    Institute of Scientific and Technical Information of China (English)

    仵安东

    2014-01-01

    The quality of a construction has great relationship with the construction technology of pile foundation enginee- ring. To improve the pile foundation engineering technology and to ensure its quality can improve the level and quality of the overal construction. This paper gives a brief introduction on the pile foundation engineering construction technology of modern construction projects.%一项建筑施工质量的好坏,很大联系就在于桩基工程的施工技术。要对桩基工程的技术进行提高、保证其质量过关,可以提高整体建筑的水平和质量。本文就现代建筑工程桩基工程施工技术方面进行了简要的介绍。

  1. Reflections and arguments in the construction of shared knowledge about the bioethical issues of genetic engineering

    Science.gov (United States)

    Zaltas, Fred David

    This qualitative inquiry reports on how metacognitive reflection was more stimulated within a context of a collective argument with a destination of shared knowledge construction. Its purpose was to investigate seventh grade students' group dilemma discussions about the bioethical issues of genetic engineering by relating the dynamics of argumentation to metacognitive mental actions involved in the construction of knowledge. Specifically examined were (1) students reflections and perceptions about the issues involved in the dilemma discussions, (2) elements of argument used during dilemma discussions that supported reasoning and thinking in the construction of knowledge, (3) metacognitive mental actions relating argument and reflective thoughts, (4) levels of metacognitive awareness, (5) levels of metacognitive awareness within argumentative structure. Focus-group interviews and discourse analysis revealed patterns regarding metacognitive strategies and reasoning, knowledge and awareness of the process of argument, and the construction of knowledge. Dilemma discussions may provide innovative learning environments in which reasoning could develop through co-construction and critical opposition fostering a metacognitive dimension of thinking.

  2. A native-like corneal construct using donor corneal stroma for tissue engineering.

    Directory of Open Access Journals (Sweden)

    Jing Lin

    Full Text Available Tissue engineering holds great promise for corneal transplantation to treat blinding diseases. This study was to explore the use of natural corneal stroma as an optimal substrate to construct a native like corneal equivalent. Human corneal epithelium was cultivated from donor limbal explants on corneal stromal discs prepared by FDA approved Horizon Epikeratome system. The morphology, phenotype, regenerative capacity and transplantation potential were evaluated by hematoxylin eosin and immunofluorescent staining, a wound healing model, and the xeno-transplantation of the corneal constructs to nude mice. An optically transparent and stratified epithelium was rapidly generated on donor corneal stromal substrate and displayed native-like morphology and structure. The cells were polygonal in the basal layer and became flattened in superficial layers. The epithelium displayed a phenotype similar to human corneal epithelium in vivo. The differentiation markers, keratin 3, involucrin and connexin 43, were expressed in full or superficial layers. Interestingly, certain basal cells were immunopositive to antibodies against limbal stem/progenitor cell markers ABCG2 and p63, which are usually negative in corneal epithelium in vivo. It suggests that this bioengineered corneal epithelium shared some characteristics of human limbal epithelium in vivo. This engineered epithelium was able to regenerate in 4 days following from a 4mm-diameter wound created by a filter paper soaked with 1 N NaOH. This corneal construct survived well after xeno-transplantation to the back of a nude mouse. The transplanted epithelium remained multilayer and became thicker with a phenotype similar to human corneal epithelium. Our findings demonstrate that natural corneal stroma is an optimal substrate for tissue bioengineering, and a native-like corneal construct has been created with epithelium containing limbal stem cells. This construct may have great potential for clinical use in

  3. Techniques for fabrication and construction of three-dimensional scaffolds for tissue engineering

    Directory of Open Access Journals (Sweden)

    Lu T

    2013-01-01

    Full Text Available Tingli Lu,1,* Yuhui Li,1,* Tao Chen1,21Key Laboratory of Space Bioscience and Biotechnology, School of Life Science, Northwestern Polytechnical University, 2Liposome Research Centre, Xi'an, China*These authors contributed equally to this workAbstract: Three-dimensional biomimetic scaffolds have widespread applications in biomedical tissue engineering because of their nanoscaled architecture, eg, nanofibers and nanopores, similar to the native extracellular matrix. In the conventional “top-down” approach, cells are seeded onto a biocompatible and biodegradable scaffold, in which cells are expected to populate in the scaffold and create their own extracellular matrix. The top-down approach based on these scaffolds has successfully engineered thin tissues, including skin, bladder, and cartilage in vitro. However, it is still a challenge to fabricate complex and functional tissues (eg, liver and kidney due to the lack of vascularization systems and limited diffusion properties of these large biomimetic scaffolds. The emerging “bottom-up” method may hold great potential to address these challenges, and focuses on fabricating microscale tissue building blocks with a specific microarchitecture and assembling these units to engineer larger tissue constructs from the bottom up. In this review, state-of-the-art methods for fabrication of three-dimensional biomimetic scaffolds are presented, and their advantages and drawbacks are discussed. The bottom-up methods used to assemble microscale building blocks (eg, microscale hydrogels for tissue engineering are also reviewed. Finally, perspectives on future development of the bottom-up approach for tissue engineering are addressed.Keywords: three-dimensional, extracellular matrix scaffolds, bottom-up, tissue engineering

  4. Simple-current algebra constructions of 2+1-dimensional topological orders

    Science.gov (United States)

    Schoutens, Kareljan; Wen, Xiao-Gang

    2016-01-01

    Self-consistent (non-)Abelian statistics in 2+1 dimensions (2+1D) are classified by modular tensor categories (MTCs). In recent works, a simplified axiomatic approach to MTCs, based on fusion coefficients Nki j and spins si, was proposed. A numerical search based on these axioms led to a list of possible (non-)Abelian statistics, with rank up to N =7 . However, there is no guarantee that all solutions to the simplified axioms are consistent and can be realized by bosonic physical systems. In this paper, we use simple-current algebra to address this issue. We explicitly construct many-body wave functions, aiming to realize the entries in the list (i.e., realize their fusion coefficients Nki j and spins si). We find that all entries can be constructed by simple-current algebra plus conjugation under time-reversal symmetry. This supports the conjecture that simple-current algebra is a general approach that allows us to construct all (non-)Abelian statistics in 2+1D. It also suggests that the simplified theory based on (Nki j,si) is a classifying theory at least for simple bosonic 2+1D topological orders (up to invertible topological orders).

  5. E-COCOMO: The Extended COst Constructive MOdel for Cleanroom Software Engineering

    Directory of Open Access Journals (Sweden)

    Hitesh KUMAR SHARMA

    2014-02-01

    Full Text Available Mistakes create rework. Rework takes time and increases costs. The traditional software engineering methodology defines the ratio of Design:Code:Test as 40:20:40. As we can easily see that 40% time and efforts are used in testing phase in traditional approach, that means we have to perform rework again if we found some bugs in testing phase. This rework is being performed after Design and code phase. This rework will increase the cost exponentially. The cleanroom software engineering methodology controls the exponential growth in cost by removing this rework. It says that "do the work correct in first attempt and move to next phase after getting the proof of correctness". This new approach minimized the rework and reduces the cost in the exponential ratio. Due to the removal of testing phase, the COCOMO (COst COnstructive MOdel used for the traditional engineering is not directly applicable in cleanroom software engineering. The traditional cost drivers used for traditional COCOMO needs to be revised. We have proposed the Extended version of COCOMO (i.e. E-COCOMO in which we have incorporated some new cost drivers. This paper explains the proposed E-COCOMO and the detailed description of proposed new cost driver.

  6. Modifications to the current WAsP engine for Online WAsP

    DEFF Research Database (Denmark)

    Peña, Alfredo; Troen, Ib; Bechmann, Andreas

    This report documents the work performed in work package 3 of the Online WAsP EUDP project (Online WAsP for Small Wind Turbines). Specifically it is deliverable D3.1 "Report on modifications required to update current WAsP calculation engine".......This report documents the work performed in work package 3 of the Online WAsP EUDP project (Online WAsP for Small Wind Turbines). Specifically it is deliverable D3.1 "Report on modifications required to update current WAsP calculation engine"....

  7. Concept document of the repository-based software engineering program: A constructive appraisal

    Science.gov (United States)

    1992-01-01

    A constructive appraisal of the Concept Document of the Repository-Based Software Engineering Program is provided. The Concept Document is designed to provide an overview of the Repository-Based Software Engineering (RBSE) Program. The Document should be brief and provide the context for reading subsequent requirements and product specifications. That is, all requirements to be developed should be traceable to the Concept Document. Applied Expertise's analysis of the Document was directed toward assuring that: (1) the Executive Summary provides a clear, concise, and comprehensive overview of the Concept (rewrite as necessary); (2) the sections of the Document make best use of the NASA 'Data Item Description' for concept documents; (3) the information contained in the Document provides a foundation for subsequent requirements; and (4) the document adequately: identifies the problem being addressed; articulates RBSE's specific role; specifies the unique aspects of the program; and identifies the nature and extent of the program's users.

  8. Magnetic resonance microscopy for monitoring osteogenesis in tissue-engineered construct in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Xu Huihui [Bioengineering Department (MC 063), University of Illinois at Chicago, 851 South Morgan Street, Chicago, IL 60607-7052 (United States); Othman, Shadi F [Bioengineering Department (MC 063), University of Illinois at Chicago, 851 South Morgan Street, Chicago, IL 60607-7052 (United States); Hong Liu [Bioengineering Department (MC 063), University of Illinois at Chicago, 851 South Morgan Street, Chicago, IL 60607-7052 (United States); Peptan, Ioana A [Bioengineering Department (MC 063), University of Illinois at Chicago, 851 South Morgan Street, Chicago, IL 60607-7052 (United States); Magin, Richard L [Bioengineering Department (MC 063), University of Illinois at Chicago, 851 South Morgan Street, Chicago, IL 60607-7052 (United States)

    2006-02-07

    Magnetic resonance microscopy (MRM) is used to monitor osteogenesis in tissue-engineered constructs. Measurements of the developing tissue's MR relaxation times (T{sub 1} and T{sub 2}), apparent diffusion coefficient (ADC) and elastic shear modulus were conducted over a 4-week growth period using an 11.74 T Bruker spectrometer with an imaging probe adapted for MR elastography (MRE). Both the relaxation times and the ADC show a statistically significant decrease after only one week of tissue development while the tissue stiffness increases progressively during the first two weeks of in vitro growth. The measured MR parameters are correlated with histologically monitored osteogenic tissue development. This study shows that MRM can provide quantitative data with which to characterize the growth and development of tissue-engineered bone.

  9. Construction and characterization of VL-VH tail-parallel genetically engineered antibodies against staphylococcal enterotoxins.

    Science.gov (United States)

    He, Xianzhi; Zhang, Lei; Liu, Pengchong; Liu, Li; Deng, Hui; Huang, Jinhai

    2015-03-01

    Staphylococcal enterotoxins (SEs) produced by Staphylococcus aureus have increasingly given rise to human health and food safety. Genetically engineered small molecular antibody is a useful tool in immuno-detection and treatment for clinical illness caused by SEs. In this study, we constructed the V(L)-V(H) tail-parallel genetically engineered antibody against SEs by using the repertoire of rearranged germ-line immunoglobulin variable region genes. Total RNA were extracted from six hybridoma cell lines that stably express anti-SEs antibodies. The variable region genes of light chain (V(L)) and heavy chain (V(H)) were cloned by reverse transcription PCR, and their classical murine antibody structure and functional V(D)J gene rearrangement were analyzed. To construct the eukaryotic V(H)-V(L) tail-parallel co-expression vectors based on the "5'-V(H)-ivs-IRES-V(L)-3'" mode, the ivs-IRES fragment and V(L) genes were spliced by two-step overlap extension PCR, and then, the recombined gene fragment and V(H) genes were inserted into the pcDNA3.1(+) expression vector sequentially. And then the constructed eukaryotic expression clones termed as p2C2HILO and p5C12HILO were transfected into baby hamster kidney 21 cell line, respectively. Two clonal cell lines stably expressing V(L)-V(H) tail-parallel antibodies against SEs were obtained, and the antibodies that expressed intracytoplasma were evaluated by enzyme-linked immunosorbent assay, immunofluorescence assay, and flow cytometry. SEs can stimulate the expression of some chemokines and chemokine receptors in porcine IPEC-J2 cells; mRNA transcription level of four chemokines and chemokine receptors can be blocked by the recombinant SE antibody prepared in this study. Our results showed that it is possible to get functional V(L)-V(H) tail-parallel genetically engineered antibodies in same vector using eukaryotic expression system.

  10. Savannah River Plant engineering, design, and construction history of ``S`` projects and other work, January 1961--December 1964. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    1970-03-01

    The work described in this volume of ``S`` Projects History is an extension of the type of work described in Volume I. E.I. du Pont de flemours & Company had entered into Contract AT (07-2)-l with the United States Atomic Energy Commission to develop, design, construct, install, and operate facilities to produce heavy water, fissionable materials, and related products. Under this contract,, Du Pont constructed and operated the Savannah River Plant. The engineering, design, and construction for most of the larger ``S`` projects was performed by the Engineering DeDartment. For some of the large and many of the smaller projects the Engineering Department was responsible only for the construction because the Atomic Energy Division (AED) of the Explosives Department handled the other phases. The Engineering Department Costruction Division also performed the physical work for many of the plant work orders. This volume includes a general description of the Du Pont Engineering Department activities pertaining to the engineering, design, and construction of the ``S`` projects at the Savannah River Plant; brief summaries of the projects and principal work requests; and supplementary informaticn on a few subjects in Volume I for which final data was not available at the closing date. Projects and other plant engineering work which were handled entirely by the Explosives Department -- AED are not included in this history.

  11. Nano/microfibrous polymeric constructs loaded with bioactive agents and designed for tissue engineering applications: a review.

    Science.gov (United States)

    Puppi, Dario; Zhang, Xuanmiao; Yang, Likai; Chiellini, Federica; Sun, Xun; Chiellini, Emo

    2014-10-01

    Nano/microfibrous polymeric constructs present various inherent advantages, such as highly porous architecture and high surface to volume ratio, making them attractive for tissue engineering purposes. Electrospinning is the most preferred technique for the fabrication of polymeric nanofibrous assemblies that can mimic the physical functions of native extracellular matrix greatly favoring cells attachment and thus influencing their morphology and activities. Different approaches have been developed to apply polymeric microfiber fabrication techniques (e.g. wet-spinning) for the obtainment of scaffolds with a three-dimensional network of micropores suitable for effective cells migration. Progress in additive manufacturing technology has led to the development of complex scaffold's shapes and microfibrous structures with a high degree of automation, good accuracy and reproducibility. Various loading methods, such as direct blending, coaxial electrospinning and microparticles incorporation, are enabling to develop customized strategies for the biofunctionalization of nano/microfibrous scaffolds with a tailored kinetics of release of different bioactive agents, ranging from small molecules, such as antibiotics, to protein drugs, such as growth factors, and even cells. Recent activities on the combination of different processing techniques and loading methods for the obtainment of biofunctionalized polymeric constructs with a complex multiscale structure open new possibilities for the development of biomimetic scaffolds endowed with a hierarchical architecture and a sophisticated release kinetics of different bioactive agents. This review is aimed at summarizing current advances in technologies and methods for manufacturing nano/microfibrous polymeric constructs suitable as tissue engineering scaffolds, and for their combination with different bioactive agents to promote tissue regeneration and therapeutic effects.

  12. Construction of tissue-engineered cartilage using human placenta-derived stem cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Human placenta-derived stem cells (hPDSCs) were isolated by trypsinization and further induced into cartilage cells in vitro.The engineered cartilage was constructed by combining hPDSCs with collagen sponge and the cartilage formation was observed by implantation into nude mice.Results showed that hPDSCs featured mesenchymal stem cells and maintained proliferation in vitro for over 30 passages while remaining undifferentiated.All results indicated that hPDSCs have the potential to differentiate into functional cartilage cells in vitro when combined with collagen sponge,which provided experimental evidence for prospective clinical application.

  13. Advancing Integrated STEM Learning through Engineering Design: Sixth-Grade Students' Design and Construction of Earthquake Resistant Buildings

    Science.gov (United States)

    English, Lyn D.; King, Donna; Smeed, Joanna

    2017-01-01

    As part of a 3-year longitudinal study, 136 sixth-grade students completed an engineering-based problem on earthquakes involving integrated STEM learning. Students employed engineering design processes and STEM disciplinary knowledge to plan, sketch, then construct a building designed to withstand earthquake damage, taking into account a number of…

  14. BENEFICIAL EFFECTS OF EXOGENOUS CROSSLINKING AGENTS ON SELF-ASSEMBLED TISSUE ENGINEERED CARTILAGE CONSTRUCT BIOMECHANICAL PROPERTIES.

    Science.gov (United States)

    Elder, Benjamin D; Mohan, Arvind; Athanasiou, Kyriacos A

    2011-04-01

    As articular cartilage is unable to repair itself, there is a tremendous clinical need for a tissue engineered replacement tissue. Current tissue engineering efforts using the self-assembly process have demonstrated promising results, but the biomechanical properties remain at roughly 50% of native tissue. The objective of this study was to determine the feasibility of using exogenous crosslinking agents to enhance the biomechanical properties of a scaffoldless cartilage tissue engineering approach. Four crosslinking agents (glutaraldehyde, ribose, genipin, and methylglyoxal) were applied each at a single concentration and single application time. It was determined that ribose application resulted in a significant 69% increase in Young's modulus, a significant 47% increase in ultimate tensile strength, as well as a trend toward a significant increase in aggregate modulus. Additionally, methylglyoxal application resulted in a significant 58% increase in Young's modulus. No treatments altered the biochemical content of the tissue. To our knowledge, this is the first study to examine the use of exogenous crosslinking agents on any tissue formed using a scaffoldless tissue engineering approach. In particular, this study demonstrates that a one-time treatment with crosslinking agents can be employed effectively to enhance the biomechanical properties of tissue engineered articular cartilage. The results are exciting, as they demonstrate the feasibility of using exogenous crosslinking agents to enhance the biomechanical properties without the need for increased glycosaminoglycan (GAG) and collagen content.

  15. Construction and evaluation of urinary bladder bioreactor for urologic tissue-engineering purposes.

    LENUS (Irish Health Repository)

    Davis, Niall F

    2012-01-31

    OBJECTIVE: To design and construct a urinary bladder bioreactor for urologic tissue-engineering purposes and to compare the viability and proliferative activity of cell-seeded extracellular matrix scaffolds cultured in the bioreactor with conventional static growth conditions. MATERIALS AND METHODS: A urinary bladder bioreactor was designed and constructed to replicate physiologic bladder dynamics. The bioreactor mimicked the filling pressures of the human bladder by way of a cyclical low-delivery pressure regulator. In addition, cell growth was evaluated by culturing human urothelial cells (UCs) on porcine extracellular matrix scaffolds in the bioreactor and in static growth conditions for 5 consecutive days. The attachment, viability, and proliferative potential were assessed and compared with quantitative viability indicators and by fluorescent markers for intracellular esterase activity and plasma membrane integrity. Scaffold integrity was characterized with scanning electron microscopy and 4\\

  16. Semantic snippet construction for search engine results based on segment evaluation

    CERN Document Server

    Kuppusamy, K S

    2012-01-01

    The result listing from search engines includes a link and a snippet from the web page for each result item. The snippet in the result listing plays a vital role in assisting the user to click on it. This paper proposes a novel approach to construct the snippets based on a semantic evaluation of the segments in the page. The target segment(s) is/are identified by applying a model to evaluate segments present in the page and selecting the segments with top scores. The proposed model makes the user judgment to click on a result item easier since the snippet is constructed semantically after a critical evaluation based on multiple factors. A prototype implementation of the proposed model confirms the empirical validation.

  17. Construction of three-dimensional vascularized cardiac tissue with cell sheet engineering.

    Science.gov (United States)

    Sakaguchi, Katsuhisa; Shimizu, Tatsuya; Okano, Teruo

    2015-05-10

    Construction of three-dimensional (3D) tissues with pre-isolated cells is a promising achievement for novel medicine and drug-discovery research. Our laboratory constructs 3D tissues with an innovative and unique method for layering multiple cell sheets. Cell sheets maintain a high-efficiently regenerating function, because of the higher cell density and higher transplantation efficiency, compared to other cell-delivery methods. Cell sheets have already been applied in clinical applications for regenerative medicine in treating patients with various diseases. Therefore, in our search to develop a more efficient treatment with cell sheets, we are constructing 3D tissues by layering cell sheets. Native animal tissues and organs have an abundance of capillaries to supply oxygen and nutrients, and to remove waste molecules. In our investigation of vascularized cardiac cell sheets, we have found that endothelial cells within cell sheets spontaneously form blood vessel networks as in vivo capillaries. To construct even thicker 3D tissues by layering multiple cell sheets, it is critical to have a medium or blood flow within the vascular networks of the cell sheets. Therefore, to perfuse medium or blood in the cell sheet vascular network to maintain the viability of all cells, we developed two types of vascular beds; (1) a femoral muscle-based vascular bed, and (2) a synthetic collagen gel-based vascular bed. Both vascular beds successfully provide the critical flow of culture medium, which allows 12-layer cell sheets to survive. Such bioreactor systems, when combined with cell sheet engineering techniques, have produced functional vascularized 3D tissues. Here we explain and discuss the various processes to obtain vascular networks by properly connecting cell sheets and the engineering of 3D tissues. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Nanostructured 3D Constructs Based on Chitosan and Chondroitin Sulphate Multilayers for Cartilage Tissue Engineering

    Science.gov (United States)

    Silva, Joana M.; Georgi, Nicole; Costa, Rui; Sher, Praveen; Reis, Rui L.; Van Blitterswijk, Clemens A.; Karperien, Marcel; Mano, João F.

    2013-01-01

    Nanostructured three-dimensional constructs combining layer-by-layer technology (LbL) and template leaching were processed and evaluated as possible support structures for cartilage tissue engineering. Multilayered constructs were formed by depositing the polyelectrolytes chitosan (CHT) and chondroitin sulphate (CS) on either bidimensional glass surfaces or 3D packet of paraffin spheres. 2D CHT/CS multi-layered constructs proved to support the attachment and proliferation of bovine chondrocytes (BCH). The technology was transposed to 3D level and CHT/CS multi-layered hierarchical scaffolds were retrieved after paraffin leaching. The obtained nanostructured 3D constructs had a high porosity and water uptake capacity of about 300%. Dynamical mechanical analysis (DMA) showed the viscoelastic nature of the scaffolds. Cellular tests were performed with the culture of BCH and multipotent bone marrow derived stromal cells (hMSCs) up to 21 days in chondrogenic differentiation media. Together with scanning electronic microscopy analysis, viability tests and DNA quantification, our results clearly showed that cells attached, proliferated and were metabolically active over the entire scaffold. Cartilaginous extracellular matrix (ECM) formation was further assessed and results showed that GAG secretion occurred indicating the maintenance of the chondrogenic phenotype and the chondrogenic differentiation of hMSCs. PMID:23437056

  19. International evaluation of current and future requirements for environmental engineering education.

    Science.gov (United States)

    Morgenroth, E; Daigger, G T; Ledin, A; Keller, J

    2004-01-01

    The field of environmental engineering is developing as a result of changing environmental requirements. In response, environmental engineering education (E3) needs to ensure that it provides students with the necessary tools to address these challenges. In this paper the current status and future development of E3 is evaluated based on a questionnaire sent to universities and potential employers of E3 graduates. With increasing demands on environmental quality, the complexity of environmental engineering problems to be solved can be expected to increase. To find solutions environmental engineers will need to work in interdisciplinary teams. Based on the questionnaire there was a broad agreement that the best way to prepare students for these future challenges is to provide them with a fundamental education in basic sciences and related engineering fields. Many exciting developments in the environmental engineering profession will be located at the interface between engineering, science, and society. Aspects of all three areas need to be included in E3 and the student needs to be exposed to the tensions associated with linking the three.

  20. Aerospace Concurrent Engineering Design Teams: Current State, Next Steps and a Vision for the Future

    Science.gov (United States)

    Hihn, Jairus; Chattopadhyay, Debarati; Karpati, Gabriel; McGuire, Melissa; Borden, Chester; Panek, John; Warfield, Keith

    2011-01-01

    Over the past sixteen years, government aerospace agencies and aerospace industry have developed and evolved operational concurrent design teams to create novel spaceflight mission concepts and designs. These capabilities and teams, however, have evolved largely independently. In today's environment of increasingly complex missions with limited budgets it is becoming readily apparent that both implementing organizations and today's concurrent engineering teams will need to interact more often than they have in the past. This will require significant changes in the current state of practice. This paper documents the findings from a concurrent engineering workshop held in August 2010 to identify the key near term improvement areas for concurrent engineering capabilities and challenges to the long-term advancement of concurrent engineering practice. The paper concludes with a discussion of a proposed vision for the evolution of these teams over the next decade.

  1. Bending strain engineering in quantum spin hall system for controlling spin currents

    Science.gov (United States)

    Huang, Bing; Jin, Kyung-Hwan; Cui, Bin; Zhai, Feng; Mei, Jiawei; Liu, Feng

    2017-06-01

    Quantum spin Hall system can exhibit exotic spin transport phenomena, mediated by its topological edge states. Here the concept of bending strain engineering to tune the spin transport properties of a quantum spin Hall system is demonstrated. We show that bending strain can be used to control the spin orientation of counter-propagating edge states of a quantum spin system to generate a non-zero spin current. This physics mechanism can be applied to effectively tune the spin current and pure spin current decoupled from charge current in a quantum spin Hall system by control of its bending curvature. Furthermore, the curved quantum spin Hall system can be achieved by the concept of topological nanomechanical architecture in a controllable way, as demonstrated by the material example of Bi/Cl/Si(111) nanofilm. This concept of bending strain engineering of spins via topological nanomechanical architecture affords a promising route towards the realization of topological nano-mechanospintronics.

  2. [Construction of guided bone regeneration membrane by tissue engineering in vitro].

    Science.gov (United States)

    Huang, Lanfeng; Qi, Xin; Liu, Jianguo; Xu, Xinxiang

    2004-08-01

    In this study, porous polymer (PLA/PCL) membrane was first treated with ethanol to become hydrophilic, and then immersed into DMEM with 50% fetal bovine serum to enhance the affinity to cells. MSCs cultured in osteogenic medium were loaded into the membrane at density of 5 x 10(6)/cm2 for 7 days, and scanning electrical microscope was used to observe the growth of the MSCs. The growth of MSCs inside the constructs was functionally well, and the cells proliferated with the time of culture. We concluded from current study that the membrane had satisfactory biocompatibility and the constructs could be used to guided bone regeneration.

  3. Methods for constructing exact solutions of partial differential equations mathematical and analytical techniques with applications to engineering

    CERN Document Server

    Meleshko, Sergey V

    2005-01-01

    Differential equations, especially nonlinear, present the most effective way for describing complex physical processes. Methods for constructing exact solutions of differential equations play an important role in applied mathematics and mechanics. This book aims to provide scientists, engineers and students with an easy-to-follow, but comprehensive, description of the methods for constructing exact solutions of differential equations.

  4. [Current status of bone/cartilage tissue engineering towards clinical applications].

    Science.gov (United States)

    Ohgushi, Hajime

    2014-10-01

    Osteo/chondrogenic differentiation capabilities are seen after in vivo implantation of mesenchymal stem cells (MSCs), which are currently used for the patients having bone/cartilage defects. Importantly, the differentiation capabilities are induced by culturing technology, resulting in in vitro bone/cartilage formation. Especially, the in vitro bone tissue is useful for bone tissue regeneration. For cartilage regeneration, culture expanded chondrocytes derived from patient's normal cartilage are also used for the patients having cartilage damages. Recently, the cultured chondrocytes embedded in atelocollagen gel are obtainable as tissue engineered products distributed by Japan Tissue Engineering Co. Ltd. The products are available in the well-regulated hospitals by qualified orthopedic surgeons. The criteria for these hospitals/surgeons have been established. This review paper focuses on current status of bone/cartilage tissue engineering towards clinical applications in Japan.

  5. 浅析燃气工程施工管理%Analysis of Gas Engineering Construction Management

    Institute of Scientific and Technical Information of China (English)

    马秋礼; 杨文娜

    2011-01-01

    According to the construction features of Qinhuangclao gas engineering, the quality, progress and investment control in construction preparation, construction management and construction process of gas engineering,security of material supply,safe construction,file management,project acceptance and transfer and other contents are discussed in detail, to provide reference for the gas project construction management.%根据秦皇岛燃气工程施工特点,深入浅出的探讨燃气工程施工准备,施工管理,施工过程中的质量,进度、投资控制,材料供应保障,文明安全施工,档案管理,验收移交等一系列内容,为燃气工程施工管理提供借鉴.

  6. A Study of Current Trends and Issues Related to Technical/Engineering Design Graphics.

    Science.gov (United States)

    Clark, Aaron C.; Scales Alice

    2000-01-01

    Presents results from a survey of engineering design graphics educators who responded to questions related to current trends and issues in the profession of graphics education. Concludes that there is a clear trend in institutions towards the teaching of constraint-based modeling and computer-aided manufacturing. (Author/YDS)

  7. Getting a grip on glycans : A current overview of the metabolic oligosaccharide engineering toolbox

    NARCIS (Netherlands)

    Sminia, Tjerk J.; Zuilhof, Han; Wennekes, Tom

    2016-01-01

    This review discusses the advances in metabolic oligosaccharide engineering (MOE) from 2010 to 2016 with a focus on the structure, preparation, and reactivity of its chemical probes. A brief historical overview of MOE is followed by a comprehensive overview of the chemical probes currently available

  8. On the Estimate Method of Construction Engineering Cost Based on the RS-GA-NNA Model

    Directory of Open Access Journals (Sweden)

    Xie Zheng

    2012-07-01

    Full Text Available Given the low intelligent level and the low accuracy of valuation of civil architecture projects, we put forward in the study a constructional engineering assessment method based on Artificial Intelligence which taking advantage of data-calculation from rough set theory, genetic algorithm and neural network algorithm. First, the rough set theory is used to reduce the discrete attributes to optimize the input variables of BP neural network. And then use the global search feature of genetic algorithm to optimize the initial weight and the threshold value of BP neural network. The new algorithm covers both the global random search capability of genetic algorithm and the learning ability and robustness of neural network, thus the computational speed and accuracy have been more significantly improved than the traditional methods. To empirically analyze a case selected from a city in Hunan Province, the results show that the new algorithm model can rely on the engineering features, assess the construction costs scientifically and objectively and have high practical value.

  9. Tough and flexible CNT-polymeric hybrid scaffolds for engineering cardiac constructs.

    Science.gov (United States)

    Kharaziha, Mahshid; Shin, Su Ryon; Nikkhah, Mehdi; Topkaya, Seda Nur; Masoumi, Nafiseh; Annabi, Nasim; Dokmeci, Mehmet R; Khademhosseini, Ali

    2014-08-01

    In the past few years, a considerable amount of effort has been devoted toward the development of biomimetic scaffolds for cardiac tissue engineering. However, most of the previous scaffolds have been electrically insulating or lacked the structural and mechanical robustness to engineer cardiac tissue constructs with suitable electrophysiological functions. Here, we developed tough and flexible hybrid scaffolds with enhanced electrical properties composed of carbon nanotubes (CNTs) embedded aligned poly(glycerol sebacate):gelatin (PG) electrospun nanofibers. Incorporation of varying concentrations of CNTs from 0 to 1.5% within the PG nanofibrous scaffolds (CNT-PG scaffolds) notably enhanced fiber alignment and improved the electrical conductivity and toughness of the scaffolds while maintaining the viability, retention, alignment, and contractile activities of cardiomyocytes (CMs) seeded on the scaffolds. The resulting CNT-PG scaffolds resulted in stronger spontaneous and synchronous beating behavior (3.5-fold lower excitation threshold and 2.8-fold higher maximum capture rate) compared to those cultured on PG scaffold. Overall, our findings demonstrated that aligned CNT-PG scaffold exhibited superior mechanical properties with enhanced CM beating properties. It is envisioned that the proposed hybrid scaffolds can be useful for generating cardiac tissue constructs with improved organization and maturation.

  10. Label free cell tracking in 3D tissue engineering constructs with high resolution imaging

    Science.gov (United States)

    Smith, W. A.; Lam, K.-P.; Dempsey, K. P.; Mazzocchi-Jones, D.; Richardson, J. B.; Yang, Y.

    2014-02-01

    Within the field of tissue engineering there is an emphasis on studying 3-D live tissue structures. Consequently, to investigate and identify cellular activities and phenotypes in a 3-D environment for all in vitro experiments, including shape, migration/proliferation and axon projection, it is necessary to adopt an optical imaging system that enables monitoring 3-D cellular activities and morphology through the thickness of the construct for an extended culture period without cell labeling. This paper describes a new 3-D tracking algorithm developed for Cell-IQ®, an automated cell imaging platform, which has been equipped with an environmental chamber optimized to enable capturing time-lapse sequences of live cell images over a long-term period without cell labeling. As an integral part of the algorithm, a novel auto-focusing procedure was developed for phase contrast microscopy equipped with 20x and 40x objectives, to provide a more accurate estimation of cell growth/trajectories by allowing 3-D voxels to be computed at high spatiotemporal resolution and cell density. A pilot study was carried out in a phantom system consisting of horizontally aligned nanofiber layers (with precise spacing between them), to mimic features well exemplified in cellular activities of neuronal growth in a 3-D environment. This was followed by detailed investigations concerning axonal projections and dendritic circuitry formation in a 3-D tissue engineering construct. Preliminary work on primary animal neuronal cells in response to chemoattractant and topographic cue within the scaffolds has produced encouraging results.

  11. Evaluation of environmental management resources (ISO 14001) at civil engineering construction worksites: a case study of the community of Madrid.

    Science.gov (United States)

    Rodríguez, Gracia; Alegre, Francisco Javier; Martínez, Germán

    2011-07-01

    In recent years, significant advances have been made in business organization and management. The growing demands of clients as well as the globalization of world markets are among the many factors that have led to the establishment of systems of quality control and environmental management as a competitive strategy for businesses. When compared to other professional sectors, the construction sector has been slower to respond to environmental problems and to adopt Environmental Management Systems (EMS). In the world today the ISO 14001 standard is currently the main frame of reference used by construction companies to implement this type of management system. This article presents the results of a general study regarding the evaluation of the application of the ISO 14001 standard at civil engineering construction worksites in the Community of Madrid (Spain), specifically pertaining to requirement 4.4.1, Resources, roles, responsibilities, and authority. According to requirement 4.4.1, company executives should appoint people responsible for implementing the EMS and also specify their responsibilities and functions. The personnel designated for supervising environmental work should also have sufficient authority to establish and maintain the EMS. The results obtained were the following: - EMS supervisors did not generally possess adequate training and solid experience in construction work and in the environment. Furthermore, supervisors were usually forced to combine their environmental work with other tasks, which made their job even more difficult. - Generally speaking, supervisors were not given sufficient authority and autonomy because productivity at the construction site had priority over environmental management. This was due to the fact that the company management did not have a respectful attitude toward the environment, nor was the management actively involved in the establishment of the EMS. - Insufficient resources were allocated to the Environmental

  12. The contribution of action research in the construction of scientific knowledge in Brazilian Production Engineering

    Directory of Open Access Journals (Sweden)

    Daniela Gibertoni

    2016-06-01

    Full Text Available Abstract The main subject of this article is the action research and it has as general objective to describe the construction of knowledge in this field from the uses that Brazilian Production Engineering makes of it, aiming to recognize its contributions, potentials and limits. To achieve this goal, a literature review was carried out for a subsequent contrast with the national academic researches that use action research and show its uses. Identified these similarities, a documentary research was carried out in academic papers published in the National Meeting of Production Engineering (ENEGEP – from 1996 to 2010. The content analysis was the strategy used for data analysis and NVivo® software was used for its treatment. As a conclusion of the research, it can be stated that the use of action research in the Brazilian Production Engineering distances itself from epistemic precepts associated with it. The results of the action are more highlighted than the reflection on the mechanisms that produced it

  13. Design, Engineering, and Construction of Photosynthetic Microbial Cell Factories for Renewable Solar Fuel Production

    Energy Technology Data Exchange (ETDEWEB)

    Lindblad, Peter; Lindberg, Pia; Stensjoe, Karin (Photochemistry and Molecular Science, Dept. of Chemistry-Aangstroem Laboratory, Uppsala Univ., Uppsala (Sweden)), E-mail: Peter.Lindblad@kemi.uu.se; Oliveira, Paulo (Instituto de Biologia Molecular e Celular, Porto (Portugal)); Heidorn, Thorsten (Bioforsk-Norwegian Inst. for Agricultural and Environmental Research, Aas Oslo, (Norway))

    2012-03-15

    There is an urgent need to develop sustainable solutions to convert solar energy into energy carriers used in the society. In addition to solar cells generating electricity, there are several options to generate solar fuels. This paper outlines and discusses the design and engineering of photosynthetic microbial systems for the generation of renewable solar fuels, with a focus on cyanobacteria. Cyanobacteria are prokaryotic microorganisms with the same type of photosynthesis as higher plants. Native and engineered cyanobacteria have been used by us and others as model systems to examine, demonstrate, and develop photobiological H{sub 2} production. More recently, the production of carbon-containing solar fuels like ethanol, butanol, and isoprene have been demonstrated. We are using a synthetic biology approach to develop efficient photosynthetic microbial cell factories for direct generation of biofuels from solar energy. Present progress and advances in the design, engineering, and construction of such cyanobacterial cells for the generation of a portfolio of solar fuels, e.g., hydrogen, alcohols, and isoprene, are presented and discussed. Possibilities and challenges when introducing and using synthetic biology are highlighted

  14. Design, engineering, and construction of photosynthetic microbial cell factories for renewable solar fuel production.

    Science.gov (United States)

    Lindblad, Peter; Lindberg, Pia; Oliveira, Paulo; Stensjö, Karin; Heidorn, Thorsten

    2012-01-01

    There is an urgent need to develop sustainable solutions to convert solar energy into energy carriers used in the society. In addition to solar cells generating electricity, there are several options to generate solar fuels. This paper outlines and discusses the design and engineering of photosynthetic microbial systems for the generation of renewable solar fuels, with a focus on cyanobacteria. Cyanobacteria are prokaryotic microorganisms with the same type of photosynthesis as higher plants. Native and engineered cyanobacteria have been used by us and others as model systems to examine, demonstrate, and develop photobiological H(2) production. More recently, the production of carbon-containing solar fuels like ethanol, butanol, and isoprene have been demonstrated. We are using a synthetic biology approach to develop efficient photosynthetic microbial cell factories for direct generation of biofuels from solar energy. Present progress and advances in the design, engineering, and construction of such cyanobacterial cells for the generation of a portfolio of solar fuels, e.g., hydrogen, alcohols, and isoprene, are presented and discussed. Possibilities and challenges when introducing and using synthetic biology are highlighted.

  15. A new compensation current real-time computing method for power active filter based on double linear construction algorithm

    Institute of Scientific and Technical Information of China (English)

    LI; Zicheng; SUN; Yukun

    2006-01-01

    Considering the detection principle that "when load current is periodic current, the integral in a cycle for absolute value of load current subtracting fundamental active current is the least", harmonic current real-time detection methods for power active filter are proposed based on direct computation, simple iterative algorithm and optimal iterative algorithm. According to the direct computation method, the amplitude of the fundamental active current can be accurately calculated when load current is placed in stable state. The simple iterative algorithm and the optimal iterative algorithm provide an idea about judging the state of load current. On the basis of the direct computation method, the simple iterative algorithm, the optimal iterative algorithm and precise definition of the basic concepts such as the true amplitude of the fundamental active current when load current is placed in varying state, etc., the double linear construction idea is proposed in which the amplitude of the fundamental active current at the moment of the sample is accurately calculated by using the first linear construction and the condition which disposes the next sample is created by using the second linear construction. On the basis of the double linear construction idea, a harmonic current real-time detection method for power active filter is proposed based on the double linear construction algorithm. This method has the characteristics of small computing quantity, fine real-time performance, being capable of accurately calculating the amplitude of the fundamental active current and so on.

  16. Regenerative endodontics as a tissue engineering approach: past, current and future.

    Science.gov (United States)

    Malhotra, Neeraj; Mala, Kundabala

    2012-12-01

    With the reported startling statistics of high incidence of tooth decay and tooth loss, the current interest is focused on the development of alternate dental tissue replacement therapies. This has led to the application of dental tissue engineering as a clinically relevant method for the regeneration of dental tissues and generation of bioengineered whole tooth. Although, tissue engineering approach requires the three main key elements of stem cells, scaffold and morphogens, a conductive environment (fourth element) is equally important for successful engineering of any tissue and/or organ. The applications of this science has evolved continuously in dentistry, beginning from the application of Ca(OH)(2) in vital pulp therapy to the development of a fully functional bioengineered tooth (mice). Thus, with advances in basic research, recent reports and studies have shown successful application of tissue engineering in the field of dentistry. However, certain practical obstacles are yet to be overcome before dental tissue regeneration can be applied as evidence-based approach in clinics. The article highlights on the past achievements, current developments and future prospects of tissue engineering and regenerative therapy in the field of endodontics and bioengineered teeth (bioteeth). © 2012 The Authors. Australian Endodontic Journal © 2012 Australian Society of Endodontology.

  17. Application of new optical coherence elastography to monitor the mineralization processing in bone tissue engineering constructs

    Science.gov (United States)

    Guan, Guangying; Song, Shaozhen; Huang, Zhihong; Yang, Ying

    2015-03-01

    Generation of functional tissue in vitro through tissue engineering technique is a promising direction to repair and replace malfunctioned organ and tissue in the modern medicine for various diseases which could not been treated well by conventional therapy. Similar to the embryo development, the generation of tissue in vitro is a highly dynamic processing. Obtaining the feedback of the processing real time is highly demanded. In this study, a new methodology has been explored aiming to monitor the morphological and mechanical property alteration of bone tissue engineering constructs simultaneously. Optical coherence elastography (OCE) equipped with a LDS V201 permanent magnet shaker and a modulated acoustic radiation force (ARF) to provide a vibration signal, has been used for the real time and non-destructive monitoring. A phantom construct system has been used to optimize the measurement conditions in which agar hydrogel with concentration from 0, 0.75 to 2% with/without hydroxyappatite particles have been injected to 3D porous poly (lactic acid) scaffolds to simulate the collagenous extracellular matrix (ECM) and mineralized ECM. The structural and elastography images of the constructs have clearly demonstrated the linear relation with the increased mechanical property versus the increase of agar concentration within the pores of the scaffolds. The MG63 bone cells seeded in the scaffolds and cultured for 4 weeks have been monitored by the established protocol exhibiting the increased mechanical strength in the pore wall where the ECM or mineralized ECM was assumed to be formed in comparison to empty pores. This study confirms that OCE-ARF could become a valuable tool in regenerative medicine to assess the biological events during in vitro culture and conditioning.

  18. Analogy and construction of meaning in science teaching physics for engineering students

    Directory of Open Access Journals (Sweden)

    Thamara FAGÚNDEZ ZAMBRANO

    2011-12-01

    Full Text Available Normal 0 21 false false false ES X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif"; mso-bidi-font-family:"Times New Roman";} An analogy can be interpreted as a structured mapping between two domains, one called domain-domain and another named source-goal. This is one of functions can play an analogy, and this function we are interested in this work to analyze how specific an analogy involved in construction and justification of new knowledge. The research finds about the use of analogies as a teaching resource are three teachers experienced in college physics classes. More specifically on the role of that resource in the construction of scientific knowledge and its contribution the teaching and learning of college-level physics and general training of the engineering student. The context of the study is Faculty of Engineering, University of Carabobo, Venezuela. The approach methodology is qualitative. This is a descriptive-interpretative cases study.  Analysis and results to identify and classify analogies by use given by teachers and their contribution to the construction of meaning scientists. Implications for improving teaching practice are extracted

  19. Is the Current Way of Constructing Corporate Authority Records Still Useful?

    Directory of Open Access Journals (Sweden)

    Qiang Jin

    2005-06-01

    Full Text Available Catalogers have been establishing corporate body name headings (and other entities in their original language in the official form, as they appear most frequently on the title pages of publications for print publications, for many years. A random sample of corporate headings from the Library of Congress Name Authority File created during 1998–2002 was searched on the Web via Google to find corporate Web pages. The purpose of this research is to begin to answer the question: Does the current way of constructing corporate authority records still help users find resources by and about corporate bodies in the online public access catalog in this Web-oriented environment?

  20. 工民建工程施工管理的现状问题与对策%Analysis of the Status Problems and Countermeasures of Civil Engineering Construction Management

    Institute of Scientific and Technical Information of China (English)

    潘海滨

    2013-01-01

    笔者长期从事建筑工程现场施工管理工作,本文首先对我国目前工民建工程施工管理的现状进行了分析,并根据现状中存在的问题提出了相应的对策,以提高工程的施工管理质量。%In this article, the author engaged in site construct-ion management of engineering construction for a long time. This article first carries out the analysis of the status quo of Chinese current civil engineering construction management and put forward the corresponding countermeasures based on the problems in the current situation in order to improve the construction management quality of project.

  1. In vivo noninvasive monitoring of dissolved oxygen concentration within an implanted tissue-engineered pancreatic construct.

    Science.gov (United States)

    Goh, Fernie; Sambanis, Athanassios

    2011-09-01

    The function of an implanted tissue-engineered pancreatic construct is influenced by many in vivo factors; however, assessing its function is based primarily on end physiologic effects. As oxygen significantly affects cell function, we established a dual perfluorocarbon method that utilizes (19)F nuclear magnetic resonance spectroscopy, with perfluorocarbons as oxygen concentration markers, to noninvasively monitor dissolved oxygen concentration (DO) in βTC-tet cell-containing alginate beads and at the implantation milieu. Beads were implanted in the peritoneal cavity of normal and streptozotocin-induced diabetic mice. Using this method, the feasibility of acquiring real-time in vivo DO measurements was demonstrated. Results showed that the mouse peritoneal environment is hypoxic and the DO is further reduced when βTC-tet cell constructs were implanted. The DO within cell-containing beads decreased considerably over time and could be correlated with the relative changes in the number of viable encapsulated cells. The reduction of construct DO due to the metabolic activity of the βTC-tet cells was also compatible with the implant therapeutic function, as observed in the reversal of hyperglycemia in diabetic mice. The importance of these findings in assessing implant functionality and host animal physiology is discussed. © Mary Ann Liebert, Inc.

  2. 建筑工程项目施工管理的创新探讨%Discussion on the Innovation of Construction Management in Construction Engineering Projects

    Institute of Scientific and Technical Information of China (English)

    梁煜

    2013-01-01

    With the increase in construction engineering proj-ects, it’s imperative to strengthen the innovation of constructio-n management of construction engineering projects. In this art-icle, the author mainly analysis of the construction manageme-nt innovation problems, the inevitability of innovation, prince-ples and programs of the construction engineering projects, ho-ping to provide a reference for future similar works.%  随着建筑工程项目的增多,加强建筑工程项目施工管理的创新势在必行。本文主要对建筑工程项目施工管理创新存在的问题,创新的必然性、原则和方案进行了分析,希望能为今后类似的工作提供一定的参考。

  3. Constructed wetlands, 1991-2011: a review of research development, current trends, and future directions.

    Science.gov (United States)

    Zhi, Wei; Ji, Guodong

    2012-12-15

    This study explores a bibliometric approach to quantitatively evaluate global scientific constructed wetlands research, and statistically assess current trends, and future directions using the Science Citation Index Expanded (SCI-EXPANDED) database from 1991 to 2011. Articles referencing constructed wetlands were analyzed by accessing the following: publication language, output characteristics, publication performance by country and institution, author keywords, title words, and KeyWords Plus. Synthetically analyzing three keyword types, we concluded that the dominant constructed wetlands research hotspots from 1991 to 2011 included water, nutrients, plants, and flow. These four hotspots remained the most dominant research areas throughout our study period, and are predicted to remain the top research emphases in the near future. "Soil" also exhibited a notable increase since 2005, and is likely to become another notable area of research interest in the future. "Phytoremediation" and "horizontal" were not identified in 1991-1995, but exhibited marked increases from 136th (0.5%) and 169th (0.7%) in 1996-2000, to 9th (3.8%) and 11th (4.3%) in 2006-2011, respectively. Therefore, given the heightened attention during the last 15 years, these topics are likely to become a primary research focus in upcoming years.

  4. Mesh optimization for microbial fuel cell cathodes constructed around stainless steel mesh current collectors

    KAUST Repository

    Zhang, Fang

    2011-02-01

    Mesh current collectors made of stainless steel (SS) can be integrated into microbial fuel cell (MFC) cathodes constructed of a reactive carbon black and Pt catalyst mixture and a poly(dimethylsiloxane) (PDMS) diffusion layer. It is shown here that the mesh properties of these cathodes can significantly affect performance. Cathodes made from the coarsest mesh (30-mesh) achieved the highest maximum power of 1616 ± 25 mW m-2 (normalized to cathode projected surface area; 47.1 ± 0.7 W m-3 based on liquid volume), while the finest mesh (120-mesh) had the lowest power density (599 ± 57 mW m-2). Electrochemical impedance spectroscopy showed that charge transfer and diffusion resistances decreased with increasing mesh opening size. In MFC tests, the cathode performance was primarily limited by reaction kinetics, and not mass transfer. Oxygen permeability increased with mesh opening size, accounting for the decreased diffusion resistance. At higher current densities, diffusion became a limiting factor, especially for fine mesh with low oxygen transfer coefficients. These results demonstrate the critical nature of the mesh size used for constructing MFC cathodes. © 2010 Elsevier B.V. All rights reserved.

  5. Current Advancements and Strategies in Tissue Engineering for Wound Healing: A Comprehensive Review

    Science.gov (United States)

    Ho, Jasmine; Walsh, Claire; Yue, Dominic; Dardik, Alan; Cheema, Umber

    2017-01-01

    Significance: With an aging population leading to an increase in diabetes and associated cutaneous wounds, there is a pressing clinical need to improve wound-healing therapies. Recent Advances: Tissue engineering approaches for wound healing and skin regeneration have been developed over the past few decades. A review of current literature has identified common themes and strategies that are proving successful within the field: The delivery of cells, mainly mesenchymal stem cells, within scaffolds of the native matrix is one such strategy. We overview these approaches and give insights into mechanisms that aid wound healing in different clinical scenarios. Critical Issues: We discuss the importance of the biomimetic niche, and how recapitulating elements of the native microenvironment of cells can help direct cell behavior and fate. Future Directions: It is crucial that during the continued development of tissue engineering in wound repair, there is close collaboration between tissue engineers and clinicians to maintain the translational efficacy of this approach. PMID:28616360

  6. 3-Dimensional functionalized polycaprolactone-hyaluronic acid hydrogel constructs for bone tissue engineering.

    Science.gov (United States)

    Hamlet, Stephen M; Vaquette, Cedryck; Shah, Amit; Hutmacher, Dietmar W; Ivanovski, Saso

    2017-04-01

    Alveolar bone regeneration remains a significant clinical challenge in periodontology and dental implantology. This study assessed the mineralized tissue forming potential of 3-D printed medical grade polycaprolactone (mPCL) constructs containing osteoblasts (OB) encapsulated in a hyaluronic acid (HA)-hydrogel incorporating bone morphogenetic protein-7 (BMP-7). HA-hydrogels containing human OB ± BMP-7 were prepared. Cell viability, osteogenic gene expression, mineralized tissue formation and BMP-7 release in vitro, were assessed by fluorescence staining, RT-PCR, histological/μ-CT examination and ELISA respectively. In an athymic rat model, subcutaneous ectopic mineralized tissue formation in mPCL-hydrogel constructs was assessed by μ-CT and histology. Osteoblast encapsulation in HA-hydrogels did not detrimentally effect cell viability, and 3-D culture in osteogenic media showed mineralized collagenous matrix formation after 6 weeks. BMP-7 release from the hydrogel was biphasic, sustained and increased osteogenic gene expression in vitro. After 4 weeks in vivo, mPCL-hydrogel constructs containing BMP-7 formed significantly more volume (mm(3) ) of vascularized bone-like tissue. Functionalized mPCL-HA hydrogel constructs provide a favourable environment for bone tissue engineering. Although encapsulated cells contributed to mineralized tissue formation within the hydrogel in vitro and in vivo, their addition did not result in an improved outcome compared to BMP-7 alone. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Engineering design and construction of the S-1 spheromak coil systems

    Energy Technology Data Exchange (ETDEWEB)

    Heitzenroeder, P.J.; Helmich, R.C.; Pereira, M.A.; Loesser, G.D.

    1981-01-01

    The Spheromak coil systems consist of a torus-shaped flux core of 1 m. major radius located within the vacuum vessel, and three pairs of euqilibrium field (EF) coils located outside the vessel. The engineering design and fabrication methods of these coil systems are the topics of this pper. Toroidal and poloidal currents are induced by the PF (poloidal field) and TF (toroidal field) windings, located in the flux core. The windings are made of water-cooled copper cables located in grooves in and around a G-10 epoxy-glass torus form.

  8. Analyzes the Application of Pile Foundation Construction in the Construction Engineering%桩基施工在建筑工程应用分析

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    The pile foundation construction is the base form, which is the most commonly used in construction engineering. This article describes the type of pile, piling pile types as wel as different foundation construction technology, analyzes the application characteristics of pile construction technology un-der different conditions so as to provide reference for the sel-ection of pile foundation construction building in the practical application of construction engineering.%  桩基工程是建筑工程最常用的基础形式。本文通过对桩基种类、打桩类型以及不同桩基施工技术的介绍,分析了不同条件下桩基施工技术的应用特点,为建筑工程实际应用中桩基施工的选取提供了参考依据。

  9. PROSPECTS OF APPLICATION OF TISSUE-ENGINEERED PANCREATIC CONSTRUCTS IN THE TREATMENT OF TYPE 1 DIABETES

    Directory of Open Access Journals (Sweden)

    G. N. Skaletskaya

    2016-01-01

    Full Text Available Allotransplantation of pancreatic islets remains the most effective method of treatment of diabetes mellitus type 1 being capable under combination of favorable conditions (suffi cient number of isolated islets, effective combination of immunosuppressive drugs to reach the recipients’ insulin independence for several years. However, the overwhelming shortage of donor pancreas and limited post-transplantation islet survival do not allow increasing the number of such transplants and their effectiveness. This review presents a critical analysis of the work done by Russian and foreign authors onto creation of tissue-engineered pancreatic constructs that may lead to the resolution of the three main pancreatic islet transplantation issues: 1 lack of donor material; 2 necessity of immunosuppressive therapy; 3 limited survival and functional activity of the islet.

  10. Linker engineering for fusion protein construction: Improvement and characterization of a GLP-1 fusion protein.

    Science.gov (United States)

    Kong, Yuelin; Tong, Yue; Gao, Mingming; Chen, Chen; Gao, Xiangdong; Yao, Wenbing

    2016-01-01

    Protein engineering has been successfully applied in protein drug discovery. Using this technology, we previously have constructed a fusion protein by linking the globular domain of adiponectin to the C-terminus of a glucagon-like peptide-1 (GLP-1) analog. Herein, to further improve its bioactivity, we reconstructed this fusion protein by introducing linker peptides of different length and flexibility. The reconstructed fusion proteins were overexpressed in Escherichia coli and purified using nickel affinity chromatography. Their agonist activity towards receptors of GLP-1 and adiponectin were assessed in vitro by using luciferase assay and AMP-activated protein kinase (AMPK) immunoblotting, respectively. The effects of the selected fusion protein on glucose and lipid metabolism were evaluated in mice. The fusion protein reconstructed using a linker peptide of AMGPSSGAPGGGGS showed high potency in activating GLP-1 receptor and triggering AMPK phosphorylation via activating the adiponectin receptor. Remarkably, the optimized fusion protein was highly effective in lowering blood glucose and lipids in mice. Collectively, these findings demonstrate that the bioactivity of this GLP-1 fusion protein can be significantly promoted by linker engineering, and indicate that the optimized GLP-1 fusion protein is a promising lead structure for anti-diabetic drug discovery.

  11. Full-thickness tissue engineered skin constructed with autogenic bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To explore the feasibility of repairing clinical cutaneous deficiency, autogenic bone marrow mesen-chymal stem cells (BMSCs) were isolated and differentiated into epidermal cells and fibroblasts in vitro supplemented with different inducing factors and biomaterials to construct functional tissue- engineered skin. The results showed that after 72 h induction, BMSCs displayed morphologic changes such as typical epidermal cell arrangement, from spindle shape to round or oval; tonofibrils, melano-somes and keratohyaline granules were observed under a transmission electronic microscope. The differentiated cells expressed epidermal stem cell surface marker CK19 (59.66% ± 4.2%) and epidermal cells differentiation marker CK10. In addition, the induced epidermal cells acquired the anti-radiation capacity featured by lowered apoptosis following exposure to UVB. On the other hand, the collagen microfibrils deposition was noticed under a transmission electronic microscope after differentiating into dermis fibroblasts; RT-PCR identified collagen type I mRNA expression in differentiated cells; radioimmunoassay detected the secretion of interleukin-6 (IL-6) and interleukin-8 (IL-8) (up to 115.06 pg/mL and 0.84 ng/mL, respectively). Further in vivo implanting BMSCs with scaffold material short-ened skin wound repair significantly. In one word, autogenic BMSCs have the potential to differentiate into epidermal cells and fibroblasts in vitro, and show clinical feasibility acting as epidermis-like and dermis-like seed cells in skin engineering.

  12. Development of a 3D cell printed construct considering angiogenesis for liver tissue engineering.

    Science.gov (United States)

    Lee, Jin Woo; Choi, Yeong-Jin; Yong, Woon-Jae; Pati, Falguni; Shim, Jin-Hyung; Kang, Kyung Shin; Kang, In-Hye; Park, Jaesung; Cho, Dong-Woo

    2016-01-12

    Several studies have focused on the regeneration of liver tissue in a two-dimensional (2D) planar environment, whereas actual liver tissue is three-dimensional (3D). Cell printing technology has been successfully utilized for building 3D structures; however, the poor mechanical properties of cell-laden hydrogels are a major concern. Here, we demonstrate the printing of a 3D cell-laden construct and its application to liver tissue engineering using 3D cell printing technology through a multi-head tissue/organ building system. Polycaprolactone (PCL) was used as a framework material because of its excellent mechanical properties. Collagen bioink containing three different types of cells-hepatocytes (HCs), human umbilical vein endothelial cells , and human lung fibroblasts--was infused into the canals of a PCL framework to induce the formation of capillary--like networks and liver cell growth. A co-cultured 3D microenvironment of the three types of cells was successfully established and maintained. The vascular formation and functional abilities of HCs (i.e., albumin secretion and urea synthesis) demonstrated that the heterotypic interaction among HCs and nonparenchymal cells increased the survivability and functionality of HCs within the collagen gel. Therefore, our results demonstrate the prospect of using cell printing technology for the creation of heterotypic cellular interaction within a structure for liver tissue engineering.

  13. Productivity improvement in engineering-procure-construct projects through a value stream based scope change management system

    OpenAIRE

    2014-01-01

    M.Ing. (Engineering Management) This dissertation provides a study of productivity improvement to project Scope Change Management (SCM) processes in the Engineer-Procure-Construct (EPC) project environment using lean techniques. The motivation for carrying out this study was, to optimise the typical scope change management systems to improve efficiency and most importantly the process productivity. It aims to present a conceptual approach to reduce bottom line impact brought about by the m...

  14. Engineering geology method of studying the suitability of the land overlying mined-out area to construction

    Energy Technology Data Exchange (ETDEWEB)

    Ma Jinrong; Peng Xiangfeng; Ding Chenjian [China University of Mining and Technology (China)

    1996-12-31

    The engineering geological problems occurring in the land overlying worked-out areas of coal mines were introduced. The methods of field investigation and experimental simulation of the engineering geological conditions of mined-out area were put forward. With the properties of reactivation of mined-out area, the suitability of the land overlying mined-put area for construction was analysed. Effective measures to strengthen the foundation soil and to protect the buildings from subsidence were given. 6 refs., 1 fig.

  15. Analysis of OPLA scaffolds for bone engineering constructs using human jaw periosteal cells.

    Science.gov (United States)

    Alexander, Dorothea; Hoffmann, Jürgen; Munz, Adelheid; Friedrich, Björn; Geis-Gerstorfer, Jürgen; Reinert, Siegmar

    2008-03-01

    For bone regeneration constructs using human jaw periosteal cells (JPC) the extent of osteoinductive ability of different three-dimensional scaffolds is not yet established. We analyzed open-cell polylactic acid (OPLA) scaffolds for their suitability as bone engineering constructs using human JPC. Cell adhesion and spreading was visualized on the surface of scaffolds by scanning electron microscopy. JPC proliferation within OPLA scaffolds was compared with proliferation within collagen and calcium phosphate scaffolds. We found a significant increase of proliferation rates in OPLA scaffolds versus Coll/CaP scaffolds at three time points. Live-measurements of oxygen consumption within the cell-seeded scaffolds indicate that the in vitro culturing time should not exceed 12-15 days. OPLA scaffolds, which were turned out to be the most beneficial for JPC growth, were chosen for osteogenic differentiation experiments with or without BMP-2. Gene expression analyses demonstrated induction of several osteogenic genes (alkaline phosphatase, osterix, Runx-2 and insulin-like growth factor) within the 3D-scaffolds after 12 days of in vitro culturing. Element analysis by EDX spectrometry of arising nodules during osteogenesis demonstrated that JPC growing within OPLA scaffolds are able to form CaP particles. We conclude that OPLA scaffolds provide a promising environment for bone substitutes using human JPC.

  16. Knowledge Management Practice in Two Australian Architecture-Engineering-Construction (AEC Companies

    Directory of Open Access Journals (Sweden)

    Patrick Zou

    2012-11-01

    Full Text Available Knowledge management (KM could be described as a management system that supports the creation, sharing and retrieving of valued information, expertise and insight within and across communities of people and related organizations using information and communication technologies and hence it is a combination of the effective application of information technlogy and management of human resources. KM is becoming a core competitive factor in construction operations. This paper presents the results of two case studies of KM practices in large AEC (architecture, engineering and construction companies through desk-top study and semi-structured interviews. The results indicate that implementing KM in AEC companies leads to competitive advantages and improved decision-making, problem solving and business performance. The results also indicateed that while technology plays an important role, top management commitment, total employee involvement, performance assessment and the culture of knowledge-learning and sharing must be considered when implementing KM. Therefore it is suggested that the implementation of KM should incorporate the company's vision, work processes, technology and culture, to improve the ability of knowledge creating, capturing, sharing, retrieving and ultimately, to improve the company's competitive advantage, decision making, problem solving and innovation.

  17. Discussion on Quality Control of Constructional Engineering Construction Process%浅谈建筑工程施工工序的质量控制

    Institute of Scientific and Technical Information of China (English)

    杨洁

    2011-01-01

    质量是企业生存和发展的生命之源,对于建筑工程企业,这一点尤为突出.建筑工程施工管理是一项全面、深入细致的工作,贯穿于整个工程的施工过程.本文先谈谈建筑工程施工管理的必要性,简要地分析影响建筑工程施工工序质量的因素,阐述建筑工程施工工序的质量控制的内容,望能对具体的工程实施起到一定的作用.%Quality is the source of the enterprise's survival and development. And it's particularly outstanding for building engineering enterprise. Construction project construction management is a comprehensive and in -depth and meticulous work, which runs through the entire process of construction of the project. This paper first talks about the necessity of building project construction management, analyzes the factors influencing the quality of building engineering construction process and demonstrates its contents hoping to guide the specific project implementation.

  18. Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy.

    Science.gov (United States)

    Gong, Ting; Heng, Boon Chin; Lo, Edward Chin Man; Zhang, Chengfei

    2016-01-01

    Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering-stem cells, scaffolds, and signaling molecules-has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration.

  19. Current Fluctuation Measurements of Amperometric Gas Sensors Constructed with Three Different Technology Procedures

    Directory of Open Access Journals (Sweden)

    Sedlak Petr

    2016-12-01

    Full Text Available Electrochemical amperometric gas sensors represent a well-established and versatile type of devices with unique features: good sensitivity and stability, short response/recovery times, and low power consumption. These sensors operate at room temperature, and therefore have been applied in monitoring air pollutants and detection of toxic and hazardous gases in a number of areas. Some drawbacks of classical electrochemical sensors are overcome by the solid polymer electrolyte (SPE based on ionic liquids. This work presents evaluation of an SPE-based amperometric sensor from the point of view of current fluctuations. The sensor is based on a novel three-electrode sensor platform with solid polymer electrolytes containing ionic liquid for detection of nitrogen dioxide − a highly toxic gas that is harmful to the environment and presenting a possible threat to human health even at low concentrations. The paper focuses on using noise measurement (electric current fluctuation measurement for evaluation of electrochemical sensors which were constructed by different fabrication processes: (i lift-off and drop-casting technology, (ii screen printing technology on a ceramic substrate and (iii screen printing on a flexible substrate.

  20. Tissue-engineered tendon constructs for rotator cuff repair in sheep.

    Science.gov (United States)

    Novakova, Stoyna S; Mahalingam, Vasudevan D; Florida, Shelby E; Mendias, Christopher L; Allen, Answorth; Arruda, Ellen M; Bedi, Asheesh; Larkin, Lisa M

    2017-06-28

    Current rotator cuff repair commonly involves the use of single or double row suture techniques, and despite successful outcomes, failure rates continue to range from 20 to 95%. Failure to regenerate native biomechanical properties at the enthesis is thought to contribute to failure rates. Thus, the need for technologies that improve structural healing of the enthesis after rotator cuff repair is imperative. To address this issue, our lab has previously demonstrated enthesis regeneration using a tissue-engineered graft approach in a sheep anterior cruciate ligament (ACL) repair model. We hypothesized that our tissue-engineered graft designed for ACL repair also will be effective in rotator cuff repair. The goal of this study was to test the efficacy of our Engineered Tissue Graft for Rotator Cuff (ETG-RC) in a rotator cuff tear model in sheep and compare this novel graft technology to the commonly used double row suture repair technique. Following a 6-month recovery, the grafted and contralateral shoulders were removed, imaged using X-ray, and tested biomechanically. Additionally, the infraspinatus muscle, myotendinous junction, enthesis, and humeral head were preserved for histological analysis of muscle, tendon, and enthesis structure. Our results showed that our ETC-RCs reached 31% of the native tendon tangent modulus, which was a modest, non-significant, 11% increase over that of the suture-only repairs. However, the histological analysis showed the regeneration of a native-like enthesis in the ETG-RC-repaired animals. This advanced structural healing may improve over longer times and may diminish recurrence rates of rotator cuff tears and lead to better clinical outcomes. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  1. Construction and assessment of hierarchical edge elements for three-dimensional computations of eddy currents

    Energy Technology Data Exchange (ETDEWEB)

    Midtgaard, Ole-Morten

    1997-12-31

    This thesis considers the feasibility of doing calculations to optimize electrical machines without the need to build expensive prototypes. It deals with the construction and assessment of new, hierarchical, hexahedral edge elements for three-dimensional computations of eddy currents with the electric vector potential formulation. The new elements, five in all, gave up to second-order approximations for both the magnetic field and the current density. Theoretical arguments showed these elements to be more economical for a given polynomial order of the approximated fields than the serendipity family of nodal elements. Further it was pointed out how the support of a source field computed by using edge elements could be made very small provided that a proper spanning tree was used in the edge element mesh. This was exploited for the voltage forcing technique, where source fields were used as basis functions, with unknown total currents in voltage forced conductors as degrees of freedom. The practical assessment of the edge elements proved the accuracy to improve with increasing polynomial order, both for local and global quantities. The most economical element was, however, one giving only complete first-order approximations for both fields. Further, the edge elements turned out to be better than the nodal elements also in practice. For the voltage forcing technique, source field basis functions which had small support, resulted in large reduction of the CPU-time for solving the main equation system, compared to source fields which had large support. The new elements can be used in a p-type adaptive scheme, and they should also be applicable for other tangentially continuous field problems. 67 refs., 34 figs., 10 tabs.

  2. Current nanoscience and nanoengineering at the Center for Nanoscale Science and Engineering

    Indian Academy of Sciences (India)

    A M Hermann; R S Singh; V P Singh

    2006-07-01

    The Center for Nanoscale Science and Engineering (CeNSE) at the University of Kentucky is a multidisciplinary group of faculty, students, and staff, with a shared vision and cutting-edge research facilities to study and develop materials and devices at the nanoscale. Current research projects at CeNSE span a number of diverse nanoscience thrusts in bio-engineering and medicine (nanosensors and nanoelectrodes, nanoparticle-based drug delivery), electronics (nanolithography, molecular electronics, nanotube FETs), nanotem-plates for electronics and gas sensors (functionalization of carbon nanotubes, aligned carbon nanotube structures for gate-keeping, e-beam lithography with nanoscale precision), and nano–optoelectronics (nanoscale photonics for laser communications, quantum confinement in photovoltaic devices, and nanostructured displays). This paper provides glimpses of this research and future directions.

  3. Current status of engineered T-cell therapy for synovial sarcoma.

    Science.gov (United States)

    Dallos, Matthew; Tap, William D; D'Angelo, Sandra P

    2016-09-01

    Synovial sarcoma is a rare soft tissue sarcoma characterized by a t(X;18) translocation, which results in a SYT-SSX gene fusion. In the metastatic setting, chemotherapy has limited, durable efficacy prompting the necessity for new therapeutic modalities. One emerging new strategy involves T-cell-directed therapy such as tumor-infiltrating lymphocytes or the development of T cells that are genetically engineered to express a T-cell receptor against a cancer testis antigen. Of these approaches, engineered T cells that recognize NY-ESO-1 are the furthest along in development. Completed and on-going clinical trials have shown promise and there are efforts to continue to optimize the current approach.

  4. Tissue engineered esophagus scaffold constructed with porcine small intestinal submucosa and synthetic polymers.

    Science.gov (United States)

    Fan, Mei-Rong; Gong, Mei; Da, Lin-Cui; Bai, Lin; Li, Xiu-Qun; Chen, Ke-Fei; Li-Ling, Jesse; Yang, Zhi-Ming; Xie, Hui-Qi

    2014-02-01

    Acellular porcine small intestinal submucosa (SIS) has been successfully used for reconstructing esophagus with half circumferential defects. However, repairing full circumferential esophageal defects with SIS has been restricted due to the latter's poor mechanical properties. In the present study, synthetic polyesters biomaterial poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and poly(lactide-co-glycolide) (PLGA) have been used to improve the mechanical properties of SIS. Feasibility of SIS/PHBHHx-PLGA composite material scaffold for esophageal tissue engineering has been assessed through a series of testing. The appropriate mixing ratio of PHBHHx and PLGA polymers has been determined as 5:5 by mechanical testing and in vitro degradation experiment. The morphology of constructed membranous and tubular scaffolds was also characterized. As confirmed by enzyme-linked immunosorbent assay, the contents of VEGF and TGF-β have respectively reached 657 ± 18 ng mL(-1) and 130 ± 4 pg mL(-1) within the SIS/PHBHHx-PLGA specimens. Biocompatibility of the SIS/PHBHHx-PLGA specimens with rat bone marrow mesenchymal stem cells (MSCs) was also evaluated by scanning electron microscopy and a live-dead cell viability assay. Actin filaments of MSCs on the composite materials were labeled. Biological safety of the extract from SIS/PHBHHx-PLGA specimens, measured as hemolysis rate, was all lower than 5%. Compared with SIS and SIS/PHBHHx-PLGA specimens, inflammatory reaction provoked by the PHBHHx-PLGA specimens in rats was however more severe. Our results have suggested that SIS/PHBHHx-PLGA composite material can offer a new approach for esophageal tissue engineering.

  5. Tissue-engineered graft constructed by self-derived cells and heterogeneous acellular matrix

    Institute of Scientific and Technical Information of China (English)

    HUANG Hui-min; WU Shao-feng; REN Hong

    2006-01-01

    Background: Endothelial and smooth muscle cells were used as seeding cells and heterogeneous acellularized matrix was used as scaffold to construct the tissue-engineered graft. Methods: A 2 weeks piglet was selected as a donor of seeding cells. Two-centimetre length of common carotid artery was dissected. Endothelial cells and smooth muscle cells were harvested by trypsin and collagenase digestion respectively. The isolated cells were cultured and expanded using routine cell culture technique.An adult sheep was used as a donor of acellularized matrix. The thoracic aorta was harvested and processed by a multi-step decellularizing technique to remove the original cells and preserve the elastic and collagen fibers. The cultured smooth muscle cells and endothelial cells were then seeded to the acellularized matrix and incubated in vitro for another 2 weeks. The cell seeded graft was then transplanted to the cell-donated piglet to substitute part of the native pulmonary artery. Results: The cultured cells from piglet were characterized as endothelial cells by the presence of specific antigens vWF and CD31, and smooth muscle cells by the presence of specific antigen α-actin on the cell surface respectively with immunohistochemical technique. After decellularizing processing for the thoracic aorta from sheep, all the cellular components were extracted and elastic and collagen fibers kept their original morphology and structure. The maximal load of acellular matrix was decreased and 20% lower than that of untreated thoracic aorta, but the maximal tensions between them were not different statistically and they had similar load-tension curves. Three months after transplantation, the animal was sacrificed and the graft was removed for observation. The results showed that the inner surfaces of the graft were smooth, without thrombosis and calcification. Under microscopy, a great number of growing cells could be seen and elastic and collagen fibers were abundant. Conclusion

  6. An impedance method for spatial sensing of 3D cell constructs – towards applications in tissue engineering

    DEFF Research Database (Denmark)

    Canali, Chiara; Mazzoni, Chiara; Larsen, Layla Bashir

    2015-01-01

    ) cells were encapsulated in gelatin to form artificial 3D cell constructs and detected when placed in different positions inside large gelatin scaffolds. Taken together, these results open new perspectives for impedance-based sensing technologies for non-invasive monitoring in tissue engineering...

  7. 48 CFR 227.7107-1 - Architectural designs and data clauses for architect-engineer or construction contracts.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Architectural designs and... construction involving architect-engineer services, is to obtain a unique architectural design of a building, a... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Technical Data 227.7107-1 Architectural...

  8. Projects of Iberdrola Engineering and Construction on the Flamanville 3 EPR; Proyectos de Iberdrola Ingenieria y construccion en el EPR de Flamanville 3

    Energy Technology Data Exchange (ETDEWEB)

    Zornoza, J.; Dumas, H.; Sesma, J. L.; Cubian, B.; Diaz, J. I.

    2013-06-01

    Iberdrola Engineering and Construction is participating during the last 5 years in 5 projects on the Flamanville 3 EPR, both in the nuclear island and conventional island and the pump house. These projects represent a challenge from the technical point of view due to the high requirements applicable to the project because of the experience feedback of the operator EDF and of compliance with new regulations that have emerged since the completion of the last nuclear power station in France. This paper presents the description of these projects, as well as its current status. (Author)

  9. Inter-organizational collaboration in the field of construction: the perspective of an engineering consultancy

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh

    2006-01-01

    in the building industry provides improved quality. However, new needs arise and development of new knowledge processes is required to exchange, understand and negotiate the knowledge needed in closer collaboration. Development of these knowledge processes is complicated and there is a need for both industry......In this work in progress we consider the challenges of inter-organizational collaboration in building projects to support higher quality and lower prices. The framework of Carlile (2004) is used to identify and categorize the current situation and needs of different knowledge processes: transfer......, translation and transforming. We discuss recent and ongoing initiatives at various levels within the building industry (government, industry, company). The initiatives are discussed from the viewpoint of an engineering consultancy company. The study reveals that a more integrated process across partners...

  10. Constructed Wetlands

    Science.gov (United States)

    these systems can improve water quality, engineers and scientists construct systems that replicate the functions of natural wetlands. Constructed wetlands are treatment systems that use natural processes

  11. 铁路建设工程施工总工期的确定方法%Determination Method of Railway Construction Engineering Construction Total Duration

    Institute of Scientific and Technical Information of China (English)

    江国君

    2012-01-01

    Railway construction engineering is a system engineering. In developing the construction organization design, how to reasonably determine the construction total duration is an important subject. To complete this subject, it is necessary to divide 6 boundary conditions and follow the steps and method to determine the construction total duration based on analyzing the relationship each project and construction period and the main influencing factors of total duration and according to the construction environment and the main technical standards.%铁路建设工程线长、点多、跨越区域广、建设环境复杂,涉及到线路、桥、隧及“四电“各专业,是一项系统工程。在开展施工组织设计时如何合理确定施工总工期,是一个重要课题。为完成好这一课题,须在分析各分项工程与施工工期的关系、影响施工总工期主要因素的基础上,根据建设环境和采用的主要技术标准,划分6种边界条件。并根据划分的6种边界条件,遵循一定的步骤和方法确定施工总工期。

  12. Discussion on contract management of engineering construction%谈建设工程施工合同管理

    Institute of Scientific and Technical Information of China (English)

    赵基平

    2016-01-01

    This paper introduced the definition and role of engineering construction contract,from the contract conclusion,contract performance, claims process and other aspects,elaborated the matters needing attention of construction contract management,in order to improve the contract consciousness,strengthen the contract dynamic management,realized the engineering construction period,quality,safety and other overall goals.%介绍了建设工程施工合同的定义与作用,从合同订立、合同履行、索赔处理等方面,阐述了施工合同管理的注意事项,以提高合同意识,加强合同动态管理,实现工程工期、质量、安全等总体目标。

  13. Reduced analysis and confirmatory research on co-adaptability theoretical solution to conflicting events in construction engineering projects

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The co-adaptability theoretical solution to conflicting events in construction engineering projects has three problems. First, the transformation of constraint conditions of theoretical solution is very difficult in practical engineering applications; second, some coefficients are difficult to be determined; third, there are overfull circular arithmetic operations involved in it. To resolve these problems, a new method to reduce the theoretical solution complications is proposed. By analyzing the operating mechanism of theoretical solution model, redundancies in the theoretical solution can be eliminated, and the ISM mapping with the co-adaptability solution can be set up. Based on this approach, a procedure to solve practical conflicting events in construction projects is established by replacing characteristic variables with mathematic variables. The research results show that the procedure can replace the co-adaptability theoretical solution effectively and solve practical conflicting events in construction projects.

  14. Phenomenology of plasma engine cathodes at high current rates and low pressures

    Science.gov (United States)

    Huegel, H.; Kruelle, G.

    1984-01-01

    The effects of low surrounding pressures on cathodes of arc jet engines with electromagnetic acceleration are investigated for pressure and current energies of 20 to 100 Torr. and 400 to 1000 A. Experiments with 50 mm long and 8 mm diameter tungsten-thorium cathode in a coaxial gas flow show that pre-heating of the cathode reduces the duration of the instable arc discharge and thus material loss. The use of lighter gases also reduces instability effects, as well as the use of increased pressures and a massive gas influx.

  15. Internal oscillating current-sustained RF plasmas: Parameters, stability, and potential for surface engineering

    DEFF Research Database (Denmark)

    Ostrikov, K.; Tsakadze, E.L.; Tsakadze, Z.L.;

    2005-01-01

    plasma parameters by the optical and Langmuir probes are presented. It is shown that the spatial profiles of the electron density, the effective electron temperature and plasma potential feature a great deal of the radial and axial uniformity compared with conventional sources of inductively coupled......A new source of low-frequency (0.46 MHz) inductively coupled plasmas sustained by the internal planar "unidirectional" RF current driven through a specially designed internal antenna configuration has been developed. The experimental results of the investigation of the optical and global argon...... applications and surface engineering. (c) 2005 Elsevier B.V. All rights reserved....

  16. Department of Health application for approval of construction SP-100 Ground Engineering System Test Site

    Energy Technology Data Exchange (ETDEWEB)

    1990-04-01

    The following Application For Approval of Construction is being submitted by the US Department of Energy-Richland Operations Office, for the SP-100 Ground Engineering System Test Site, which will provide a new source of radioactive emissions to the atmosphere. The US Department of Energy, the National Aeronautics and Space Administration, and the US Department of Defense have entered into an agreement to jointly develop space nuclear reactor power system technology. A ground test of a reactor is necessary to demonstrate technology readiness of this major subsystem before proceeding with the flight system development and demonstration. It is proposed that the SP-100 test reactor be tested in the existing decommissioned Plutonium Recycle Test Reactor containment building (309 Building). The reactor will be operated for at least three months and up to 2 yr. Following the test, the 309 Building will be decontaminated for potential use in other programs. It is projected this new source of emissions will contribute approximately 0.05 mrem/yr dose to the maximally exposed offsite individual. This application is being submitted in response to those projected emissions that would provide the described offsite dose. 28 refs., 9 figs., 7 tabs.

  17. Construction of a bibliographic information database for the Nuclear Science and Engineering (IX)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Whan; Oh, Jeong Hun; Choi, Kwang; Keum, Jong Yong [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-12-01

    The major goal of this project is to construct a database in nuclear science and engineering information materials, support the R and D activities of users in this field, finally to support KRISTAL(Korea Research Information for Science and Technology Access Line)'s DB through the KREONet(Korea Research Environment Open Network), as one of the five national information networks. The contents of this project are as follows: 1) Materials selection and collection, 2) Indexing and abstract preparation, 3) Data input and transmission, and 4) document delivery service. In this seventh year, 40,000 records, as total of inputted data, are added to the existing SATURN DB. These records are covered with the articles of nuclear-related core journals, proceedings, seminars, and research reports, etc. And using the Web, this project was important for users to get their needed information itself and to receive the materials of online requested information. And then it will give the chance users not only to promote the the effectiveness of R and D activities, but also to obviate the duplicated research works. 1 fig., 1 tab. (Author)

  18. THE FUNCTIONAL EFFECTIVENESS OF A CELL-ENGINEERED CONSTRUCT FOR THE REGENERATION OF ARTICULAR CARTILAGE

    Directory of Open Access Journals (Sweden)

    V. I. Sevastianov

    2015-01-01

    Full Text Available The aim of this study is an analysis of the functional effectiveness of a biomedical cell product consisting of a biopolymer microheterogeneous collagen-containing hydrogel (BMCH, human adipose-derived mesenchymal stromal cells (hADMSCs, and chondrogenic induction medium in the regeneration of articular cartilage. Materials and methods. The test model of the adjuvant arthritis was used (female Soviet Chinchilla rabbits with the further development into osteoarthrosis (OA combined with the clinical, biochemical, radiological, and histochemical trials. Results. On Day 92 of the OA model it has been found that the intra-articular introduction of a BMCH with hADMSCs into the left knee joint (n = 3 30 days after the OA modeling, as opposed to the right joint (negative control, n = 3, stimulates the regenerative processes of the cartilaginous tissue structure characterized by the formation of chondrocyte «columns», the emergence of isogenic groups in the intracellular matrix and the regeneration of its structure. Upon the intra-articular introduction of a BMCH (n = 3 such effects are markedly less pronounced. Conclusions. A significant regenerative potential of a cell-engineered construct of human articular tissue (CEC ATh has been proven. It is possible to presume that biostimulating properties of CEC ATh are due to the activating effect of a biomedical cell product on the stem cell migration processes from the surrounding tissue into the injured area with their subsequent differentiation. 

  19. MANAGING RISK FOR SUCCESS IN A SOUTH AFRICAN ENGINEERING AND CONSTRUCTION PROJECT ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    S. Chihuri

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: The role that project risk management plays in ensuring the successful delivery of engineering and construction projects in South Africa is addressed in this paper. A survey questionnaire was developed to establish approaches used for risk management, and tools and techniques for risk identification. The findings revealed that project risk management had a significant role to play in the success of projects in South Africa. Respondents whose organisations practised structured risk management processes reported success in their projects. The main challenge was found to be in the implementation of risk management tools and techniques. Thus it became apparent that widespread adoption of project risk management in South Africa seemed to be impeded by a low knowledge and skills base, especially in terms of its application.

    AFRIKAANSE OPSOMMING: Die rol wat projekrisikobestuur in die suksesvolle aflewering van ingenieurs- en konstruksieprojekte in Suid-Afrika speel word hier aangespreek.’n Vraelys is ontwikkel om benaderings tot risikobestuur asook toerusting en tegnieke vir risikoidentifisering te ondersoek. Die belangrikste bevinding is dat risikobestuur ’n belangrike rol speel in die sukses van projekte in Suid-Afrika. Die implementering van risikobestuurtoerusting en - tegnieke is aangedui as een van die grootste uitdagings wat oorkom moet word. Dit blyk dat die algemene aanvaarding van projekrisikobestuur in die Suid-Afrikaanse konteks bemoeilik word deur lae vlakke van kennis en vaardigheid.

  20. Engineering of core promoter regions enables the construction of constitutive and inducible promoters in Halomonas sp.

    Science.gov (United States)

    Li, Tingting; Li, Teng; Ji, Weiyue; Wang, Qiuyue; Zhang, Haoqian; Chen, Guo-Qiang; Lou, Chunbo; Ouyang, Qi

    2016-02-01

    Halomonas strain TD01, a newly identified halophilic bacterium, has proven to be a promising low-cost host for the production of chemicals. However, genetic manipulation in Halomonas sp. is still difficult due to the lack of well-characterized and tunable expression systems. In this study, a systematic, efficient method was exploited to construct both a constitutive promoter library and inducible promoters. Porin, a highly expressed protein in Halomonas TD01, was first identified from the Halomonas TD01 proteome. Subsequent study of the intergenic region upstream of porin led to the identification of a core promoter region, including -10 and -35 elements. By randomizing the sequence between the -35 and -10 elements, a constitutive promoter library was obtained with 310-fold variation in transcriptional activity; an inducible promoter with a >200-fold induction was built by integrating a lac operator into the core promoter region. As two complementary expression systems, the constitutive and inducible promoters were then employed to regulate the biosynthetic pathway of poly-3-hydroxybutyrate (PHB) in Halomonas TD01, demonstrating the usefulness of the expression systems, furthermore, they could be applied in future metabolic engineering of Halomonas TD strains, and the systematic method used in this study can be generalized to other less-characterized bacterial strains.

  1. Full-thickness tissue engineered skin constructed with autogenic bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    HE LiJuan; PEI XueTao; NAN Xue; WANG YunFang; GUAN LiDong; BAI CiXian; SHI ShuangShuang; YUAN HongFeng; CHEN Lin; LIU DaQing

    2007-01-01

    To explore the feasibility of repairing clinical cutaneous deficiency, autogenic bone marrow mesenchymal stem cells (BMSCs) were isolated and differentiated into epidermal cells and fibroblasts in vitro supplemented with different inducing factors and biomaterials to construct functional tissueengineered skin. The results showed that after 72 h induction, BMSCs displayed morphologic changes such as typical epidermal cell arrangement, from spindle shape to round or oval; tonofibrils, melanosomes and keratohyaline granules were observed under a transmission electronic microscope. The differentiated cells expressed epidermal stem cell surface marker CK19 (59.66%±4.2%) and epidermal cells differentiation marker CK10. In addition, the induced epidermal cells acquired the anti-radiation capacity featured by lowered apoptosis following exposure to UVB. On the other hand, the collagen microfibrils deposition was noticed under a transmission electronic microscope after differentiating into dermis fibroblasts; RT-PCR identified collagen type Ⅰ mRNA expression in differentiated cells;radioimmunoassay detected the secretion of interleukin-6 (IL-6) and interleukin-8 (IL-8) (up to 115.06pg/mL and 0.84 ng/mL, respectively). Further in vivo implanting BMSCs with scaffold material shortened skin wound repair significantly. In one word, autogenic BMSCs have the potential to differentiate into epidermal cells and fibroblasts in vitro, and show clinical feasibility acting as epidermis-like and dermis-like seed cells in skin engineering.

  2. Current Issues Relating to the Professional Practice of Engineering Geology in Europe

    Science.gov (United States)

    Norbury, David

    The continuing internationalisation of the construction industry in which Engineering Geologists work has resulted in significant changes in the way we work, in the way we demonstrate to others our ability to do the work, and the environment in which we carry out our work. The pace of these changes is increasing and, shortly, few of us will be able to recall the relatively relaxed and informal ways in which we worked, even as recently as the beginning of the1990s. The formalisation of engineering geologists work and reporting has come about through increasing codification of technical activities, in description of soils and rocks, in field and laboratory testing. This codification has also seen the introduction of minimum qualifications for practitioners, and this links with moves towards the international recognition of professional qualifications. The Directives on recognition have been around for comment since about 2001, and are likely to appear in European Law towards the end of 2004. This then begs the question of the need for Registration, and whether such a step would offer sufficient advantages to be of overall benefit.

  3. The Use of Online Current Awareness Services by Natural Sciences and Engineering Faculty at Western Michigan University

    Science.gov (United States)

    Leatherman, Carrie C.; Eckel, Edward J.

    2012-01-01

    Nearly every commercial database that covers natural sciences and engineering offers some type of current awareness (CA) service that provides regular updates to users on current literature in a selected field of interest. Current awareness services include e-mail alerts, tables of contents, and RSS feeds. This study was designed to find out what…

  4. A Study of Second-Year Engineering Students' Alternative Conceptions about Electric Potential, Current Intensity and Ohm's Law

    Science.gov (United States)

    Periago, M. Cristina; Bohigas, Xavier

    2005-01-01

    The aim of this research was to evaluate and analyse second-year industrial engineering and chemical engineering students prior knowledge of conceptual aspects of "circuit theory". Specifically, we focused on the basic concepts of electric potential and current intensity and on the fundamental relationship between them as expressed by Ohm's law.…

  5. A blueprint for engineering cell fate: current technologies to reprogram cell identity

    Institute of Scientific and Technical Information of China (English)

    Samantha A Morris; George Q Daley

    2013-01-01

    Human diseases such as heart failure,diabetes,neurodegenerative disorders,and many others result from the deficiency or dysfunction of critical cell types.Strategies for therapeutic tissue repair or regeneration require the in vitro manufacture of clinically relevant quantities of defined cell types.In addition to transplantation therapy,the generation of otherwise inaccessible cells also permits disease modeling,toxicology testing and drug discovery in vitro.In this review,we discuss current strategies to manipulate the identity of abundant and accessible cells by differentiation from an induced pluripotent state or direct conversion between differentiated states.We contrast these approaches with recent advances employing partial reprogramming to facilitate lineage switching,and discuss the mechanisms underlying the engineering of cell fate.Finally,we address the current limitations of the field and how the resulting cell types can be assessed to ensure the production of medically relevant populations.

  6. Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy

    Directory of Open Access Journals (Sweden)

    Ting Gong

    2016-01-01

    Full Text Available Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering—stem cells, scaffolds, and signaling molecules—has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration.

  7. Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy

    Science.gov (United States)

    Gong, Ting; Heng, Boon Chin; Lo, Edward Chin Man; Zhang, Chengfei

    2016-01-01

    Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering—stem cells, scaffolds, and signaling molecules—has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration. PMID:27069484

  8. Dual-frequency Eddy Current Non-destructive Detection of Fatigue Cracks in Compressor Discs of Aero Engines

    National Research Council Canada - National Science Library

    B. Sasi; B.P.C. Rao; T. Jayakumar

    2004-01-01

    ... related aircraft components. This paper discusses a dual-frequency eddy current testing procedure developed for inspection of compressor discs of aero engines for detecting fatigue cracks with high sensitivity and reliability...

  9. Inquiry on civil construction technology points of building engineering%建筑工程土建施工技术要点探究

    Institute of Scientific and Technical Information of China (English)

    赵成学

    2015-01-01

    依照建筑工程土建的施工要求,简单的总结了建筑工程土建施工的关键技术要点,主要包括混凝土施工、钢筋施工、砖砌筑施工、防水施工、模板施工五方面内容,以期达到提升建筑工程土建施工技术性能的目的。%According to civil construction demands of building engineering,the paper briefly summarizes critical civil construction technology points of building engineering,which mainly includes concrete construction,steel construction,brick masonry construction,waterproofing construc-tion and template construction,with a view to achieve the goal of improving civil construction technology performance of building engineering.

  10. Construction

    Science.gov (United States)

    2002-01-01

    Harbor Deepening Project, Jacksonville, FL Palm Valley Bridge Project, Jacksonville, FL Rotary Club of San Juan, San Juan, PR Tren Urbano Subway...David. What is nanotechnology? What are its implications for construction?, Foresight/CRISP Workshop on Nanotechnology, Royal Society of Arts

  11. SWITCH: a dynamic CRISPR tool for genome engineering and metabolic pathway control for cell factory construction in Saccharomyces cerevisiae.

    Science.gov (United States)

    Vanegas, Katherina García; Lehka, Beata Joanna; Mortensen, Uffe Hasbro

    2017-02-08

    The yeast Saccharomyces cerevisiae is increasingly used as a cell factory. However, cell factory construction time is a major obstacle towards using yeast for bio-production. Hence, tools to speed up cell factory construction are desirable. In this study, we have developed a new Cas9/dCas9 based system, SWITCH, which allows Saccharomyces cerevisiae strains to iteratively alternate between a genetic engineering state and a pathway control state. Since Cas9 induced recombination events are crucial for SWITCH efficiency, we first developed a technique TAPE, which we have successfully used to address protospacer efficiency. As proof of concept of the use of SWITCH in cell factory construction, we have exploited the genetic engineering state of a SWITCH strain to insert the five genes necessary for naringenin production. Next, the naringenin cell factory was switched to the pathway control state where production was optimized by downregulating an essential gene TSC13, hence, reducing formation of a byproduct. We have successfully integrated two CRISPR tools, one for genetic engineering and one for pathway control, into one system and successfully used it for cell factory construction.

  12. Testing Current and Developing Novel Therapies for NF1-Mutant Sarcomas in a Genetically Engineered Mouse Model

    Science.gov (United States)

    2015-04-01

    1   AWARD NUMBER: W81XWH-14-1-0067 TITLE: Testing Current and Developing Novel Therapies for NF1 -Mutant Sarcomas in a Genetically Engineered...Mar 2014 - 14 Mar 2015 4. TITLE AND SUBTITLE Testing Current and Developing Novel Therapies for NF1 - Mutant Sarcomas in a Genetically Engineered...Patients with Neurofibromatosis type 1 ( NF1 ) are at increased risk for developing malignant tumors of the connective tissue called soft-tissue sarcomas

  13. The Current Problems of Urban Ecological Food Construction and Counter Measures

    Directory of Open Access Journals (Sweden)

    Xiuxia LI

    2015-01-01

    Full Text Available The study presents problems of food ecological construction on municipal virescence, water environment, water ecology and landscape as well as urban ecological system of quantity, quality and capacity in our country and analysis the causes of these problems. Measures are proposed, such as knowing the meaning of municipal eco-environmental construction, increasing the food environmental protect consciousness of managers and enhancing the municipal eco-systemic construction.

  14. Analyzing Biological Performance of 3D-Printed, Cell-Impregnated Hybrid Constructs for Cartilage Tissue Engineering.

    Science.gov (United States)

    Izadifar, Zohreh; Chang, Tuanjie; Kulyk, William; Chen, Xiongbiao; Eames, B Frank

    2016-03-01

    Three-dimensional (3D) bioprinting of hybrid constructs is a promising biofabrication method for cartilage tissue engineering because a synthetic polymer framework and cell-impregnated hydrogel provide structural and biological features of cartilage, respectively. During bioprinting, impregnated cells may be subjected to high temperatures (caused by the adjacent melted polymer) and process-induced mechanical forces, potentially compromising cell function. This study addresses these biofabrication issues, evaluating the heat distribution of printed polycaprolactone (PCL) strands and the rheological property and structural stability of alginate hydrogels at various temperatures and concentrations. The biocompatibility of parameters from these studies was tested by culturing 3D hybrid constructs bioprinted with primary cells from embryonic chick cartilage. During initial two-dimensional culture expansion of these primary cells, two morphologically and molecularly distinct cell populations ("rounded" and "fibroblastic") were isolated. The biological performance of each population was evaluated in 3D hybrid constructs separately. The cell viability, proliferation, and cartilage differentiation were observed at high levels in hybrid constructs of both cell populations, confirming the validity of these 3D bioprinting parameters for effective cartilage tissue engineering. Statistically significant performance variations were observed, however, between the rounded and fibroblastic cell populations. Molecular and morphological data support the notion that such performance differences may be attributed to the relative differentiation state of rounded versus fibroblastic cells (i.e., differentiated chondrocytes vs. chondroprogenitors, respectively), which is a relevant issue for cell-based tissue engineering strategies. Taken together, our study demonstrates that bioprinting 3D hybrid constructs of PCL and cell-impregnated alginate hydrogel is a promising approach for

  15. Pathway construction and metabolic engineering for fermentative production of ectoine in Escherichia coli.

    Science.gov (United States)

    Ning, Yike; Wu, Xuejiao; Zhang, Chenglin; Xu, Qingyang; Chen, Ning; Xie, Xixian

    2016-07-01

    Ectoine is a protective agent and stabilizer whose synthesis pathway exclusively exists in select moderate halophiles. A novel established process called "bacterial milking" efficiently synthesized ectoine in moderate halophiles, however, this method places high demands on equipment and is cost prohibitive. In this study, we constructed an ectoine producing strain by introducing the ectoine synthesis pathway into Escherichia coli and improved its production capacity. Firstly, the ectABC gene cluster from Halomonas elongata was introduced into E. coli W3110 and the resultant strain synthesized 4.9g/L ectoine without high osmolarity. Subsequently, thrA encoding the bifunctional aspartokinase/homoserine dehydrogenase was deleted to weaken the competitive l-threonine branch, resulting in an increase of ectoine titer by 109%. Furthermore, a feedback resistant lysC from Corynebacterium glutamicum encoding the aspartate kinase was introduced to complement the enzymatic activity deficiency caused by thrA deletion and a 9% increase of ectoine titer was obtained. Finally, the promoter of ppc that encodes phosphoenolpyruvate carboxylase was replaced by a trc promoter, and iclR, a glyoxylate shunt transcriptional repressor gene, was deleted. The oxaloacetate pool, was thus reinforced and ectoine titer increased by 21%. The final engineered strain ECT05 (pTrcECT, pSTVLysC-CG) produced 25.1g/L ectoine by fed-batch fermentation in low salt concentration with glucose as a carbon source. The specific ectoine production and productivity was 0.8g/g DCW and 0.84gL(-)(1)h(-)(1) respectively. The overall ectoine yield was 0.11g/g of glucose.

  16. Girls' Bodily Activities in Physical Education How Current Fitness and Sport Discourses Influence Girls' Identity Construction

    Science.gov (United States)

    Walseth, Kristin; Aartun, Iselin; Engelsrud, Gunn

    2017-01-01

    Girls' identity constructions are influenced by the dominant sport, health and beauty discourses in their society. Recent research indicates that sport and health discourses embedded in physical education (PE) compete for influence. Some of these studies have illustrated how these discourses inform girls' social construction of body ideals and…

  17. Supplementation of exogenous adenosine 5'-triphosphate enhances mechanical properties of 3D cell-agarose constructs for cartilage tissue engineering.

    Science.gov (United States)

    Gadjanski, Ivana; Yodmuang, Supansa; Spiller, Kara; Bhumiratana, Sarindr; Vunjak-Novakovic, Gordana

    2013-10-01

    Formation of tissue-engineered cartilage is greatly enhanced by mechanical stimulation. However, direct mechanical stimulation is not always a suitable method, and the utilization of mechanisms underlying mechanotransduction might allow for a highly effective and less aggressive alternate means of stimulation. In particular, the purinergic, adenosine 5'-triphosphate (ATP)-mediated signaling pathway is strongly implicated in mechanotransduction within the articular cartilage. We investigated the effects of transient and continuous exogenous ATP supplementation on mechanical properties of cartilaginous constructs engineered using bovine chondrocytes and human mesenchymal stem cells (hMSCs) encapsulated in an agarose hydrogel. For both cell types, we have observed significant increases in equilibrium and dynamic compressive moduli after transient ATP treatment applied in the fourth week of cultivation. Continuous ATP treatment over 4 weeks of culture only slightly improved the mechanical properties of the constructs, without major changes in the total glycosaminoglycan (GAG) and collagen content. Structure-function analyses showed that transiently ATP-treated constructs, and in particular those based on hMSCs, had the highest level of correlation between compositional and mechanical properties. Transiently treated groups showed intense staining of the territorial matrix for GAGs and collagen type II. These results indicate that transient ATP treatment can improve functional mechanical properties of cartilaginous constructs based on chondrogenic cells and agarose hydrogels, possibly by improving the structural organization of the bulk phase and territorial extracellular matrix (ECM), that is, by increasing correlation slopes between the content of the ECM components (GAG, collagen) and mechanical properties of the construct.

  18. 从“卓越工程师”计划看软件工程专业教学建设与改革%From " Excellence Engineer" Plan to See the Software Engineering Teaching Construction and Reform

    Institute of Scientific and Technical Information of China (English)

    关培超

    2012-01-01

    本文从高校软件工程专业的实际教学现状出发,借鉴卓越工程师教育培养计划所列的培养目标,结合目前国内人才市场对软件工程专业的市场需求,分析思考了软件工程目前专业教学与建设的一些问题,并进一步探讨了如何进行适度的专业教学改革。%This article from the university software engineering practical teaching situation,draw lessons from the distinguished engineer education training program included training goal,combined with the current domestic talent market for software engineering professional market demand,analysis on the present teaching of software engineering and construction a few problems,and further discusses how to moderate the speciality teaching reform.

  19. A Pulsatile Bioreactor for Conditioning of Tissue-Engineered Cardiovascular Constructs under Endoscopic Visualization.

    Science.gov (United States)

    König, Fabian; Hollweck, Trixi; Pfeifer, Stefan; Reichart, Bruno; Wintermantel, Erich; Hagl, Christian; Akra, Bassil

    2012-07-19

    Heart valve disease (HVD) is a globally increasing problem and accounts for thousands of deaths yearly. Currently end-stage HVD can only be treated by total valve replacement, however with major drawbacks. To overcome the limitations of conventional substitutes, a new clinical approach based on cell colonization of artificially manufactured heart valves has been developed. Even though this attempt seems promising, a confluent and stable cell layer has not yet been achieved due to the high stresses present in this area of the human heart. This study describes a bioreactor with a new approach to cell conditioning of tissue engineered heart valves. The bioreactor provides a low pulsatile flow that grants the correct opening and closing of the valve without high shear stresses. The flow rate can be regulated allowing a steady and sensitive conditioning process. Furthermore, the correct functioning of the valve can be monitored by endoscope surveillance in real-time. The tubeless and modular design allows an accurate, simple and faultless assembly of the reactor in a laminar flow chamber. It can be concluded that the bioreactor provides a strong tool for dynamic pre-conditioning and monitoring of colonized heart valve prostheses physiologically exposed to shear stress.

  20. A Pulsatile Bioreactor for Conditioning of Tissue-Engineered Cardiovascular Constructs under Endoscopic Visualization

    Directory of Open Access Journals (Sweden)

    Bassil Akra

    2012-07-01

    Full Text Available Heart valve disease (HVD is a globally increasing problem and accounts for thousands of deaths yearly. Currently end-stage HVD can only be treated by total valve replacement, however with major drawbacks. To overcome the limitations of conventional substitutes, a new clinical approach based on cell colonization of artificially manufactured heart valves has been developed. Even though this attempt seems promising, a confluent and stable cell layer has not yet been achieved due to the high stresses present in this area of the human heart. This study describes a bioreactor with a new approach to cell conditioning of tissue engineered heart valves. The bioreactor provides a low pulsatile flow that grants the correct opening and closing of the valve without high shear stresses. The flow rate can be regulated allowing a steady and sensitive conditioning process. Furthermore, the correct functioning of the valve can be monitored by endoscope surveillance in real-time. The tubeless and modular design allows an accurate, simple and faultless assembly of the reactor in a laminar flow chamber. It can be concluded that the bioreactor provides a strong tool for dynamic pre-conditioning and monitoring of colonized heart valve prostheses physiologically exposed to shear stress.

  1. Fuzzy Optimization of Construction Engineering Project Schedule Based on Critical Chain Management

    OpenAIRE

    Liu, Jianbing; Ren, Hong; Junshu DU

    2013-01-01

    Critical chain management was the very important theory innovation in the development of construction project schedule management field in recent years. Compared with the traditional methods of construction project schedule management, the methods of critical chain management considered resource constraints into construction project schedule management, the construction project cycle was shortened and the efficiency was enhanced by using the dynamic thinking and circulation pattern to manage ...

  2. A simple and effective method for construction of Escherichia coli strains proficient for genome engineering.

    Science.gov (United States)

    Ryu, Young Shin; Biswas, Rajesh Kumar; Shin, Kwangsu; Parisutham, Vinuselvi; Kim, Suk Min; Lee, Sung Kuk

    2014-01-01

    Multiplex genome engineering is a standalone recombineering tool for large-scale programming and accelerated evolution of cells. However, this advanced genome engineering technique has been limited to use in selected bacterial strains. We developed a simple and effective strain-independent method for effective genome engineering in Escherichia coli. The method involves introducing a suicide plasmid carrying the λ Red recombination system into the mutS gene. The suicide plasmid can be excised from the chromosome via selection in the absence of antibiotics, thus allowing transient inactivation of the mismatch repair system during genome engineering. In addition, we developed another suicide plasmid that enables integration of large DNA fragments into the lacZ genomic locus. These features enable this system to be applied in the exploitation of the benefits of genome engineering in synthetic biology, as well as the metabolic engineering of different strains of E. coli.

  3. A simple and effective method for construction of Escherichia coli strains proficient for genome engineering.

    Directory of Open Access Journals (Sweden)

    Young Shin Ryu

    Full Text Available Multiplex genome engineering is a standalone recombineering tool for large-scale programming and accelerated evolution of cells. However, this advanced genome engineering technique has been limited to use in selected bacterial strains. We developed a simple and effective strain-independent method for effective genome engineering in Escherichia coli. The method involves introducing a suicide plasmid carrying the λ Red recombination system into the mutS gene. The suicide plasmid can be excised from the chromosome via selection in the absence of antibiotics, thus allowing transient inactivation of the mismatch repair system during genome engineering. In addition, we developed another suicide plasmid that enables integration of large DNA fragments into the lacZ genomic locus. These features enable this system to be applied in the exploitation of the benefits of genome engineering in synthetic biology, as well as the metabolic engineering of different strains of E. coli.

  4. Detection of abnormalities in the superficial zone of cartilage repaired using a tissue engineered construct derived from synovial stem cells

    OpenAIRE

    Ando, W.; FUJIE, H; Moriguchi, Y.; Nansai, R.; Shimomura, K.; DA Hart; Yoshikawa, H; Nakamura, N.

    2012-01-01

    The present study investigated the surface structure and mechanical properties of repair cartilage generated from a tissue engineered construct (TEC) derived from synovial mesenchymal stem cells at six months post-implantation compared to those of uninjured cartilage. TEC-mediated repair tissue was cartilaginous with Safranin O staining, and had comparable macro-scale compressive properties with uninjured cartilage. However, morphological assessments revealed that the superficial zone of TEC-...

  5. About the constructive and functional particularities of spark ignition engines with gasoline direct injection: experimental results

    Science.gov (United States)

    Niculae, M.; Ivan, F.; Neacsu, D.

    2017-08-01

    The paper aims to analyze and compare the environmental performances between a gasoline direct engine and a multi-point injection engine. There are analyzed the stages of emission formation during the New European Driving Cycle. The paper points out the dynamic, economic and environmental performances of spark ignition engines equipped with a GDI systems. Reason why, we believe the widespread implementation of this technology is today an immediate need.

  6. Improved repair of bone defects with prevascularized tissue-engineered bones constructed in a perfusion bioreactor.

    Science.gov (United States)

    Li, De-Qiang; Li, Ming; Liu, Pei-Lai; Zhang, Yuan-Kai; Lu, Jian-Xi; Li, Jian-Min

    2014-10-01

    Vascularization of tissue-engineered bones is critical to achieving satisfactory repair of bone defects. The authors investigated the use of prevascularized tissue-engineered bone for repairing bone defects. The new bone was greater in the prevascularized group than in the non-vascularized group, indicating that prevascularized tissue-engineered bone improves the repair of bone defects. [Orthopedics. 2014; 37(10):685-690.].

  7. Current developments of research on permafrost engineering and cold region environment:a report of the 8th International Symposium on Permafrost Engineering

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The Eighth International Symposium on Permafrost Engineering was held in Xi’an,China,October 2009.The major topics discussed in the symposium included:permafrost engineering (involving design,construction and evaluation);mitigation of frost hazards in the regions affected by seasonally frozen ground;properties of frozen soils,model development and their applications;frost hazards and periglacial environments in mountain and plateau regions;climatic,environmental and cryospheric changes;and permafrost hydrology,cold regions water resources and land uses.The papers submitted to the symposium and lectures during the meeting represented some new developments of research on cold region engineering and environment.Here we summarized the works of the symposium in topics including:Permafrost engineering;General geocryology;Properties of frozen soils:model development and their applications;And climatic,environmental and cryospheric changes.During the symposium,the attendees pointed out that future studies should pay more attention to theoretical study and engineering mechanism study,and also on interaction between climate change and cold region environments and their engineering affects.

  8. A Bio-Acoustic Levitational (BAL) Assembly Method for Engineering of Multilayered, 3D Brain-Like Constructs, Using Human Embryonic Stem Cell Derived Neuro-Progenitors.

    Science.gov (United States)

    Bouyer, Charlène; Chen, Pu; Güven, Sinan; Demirtaş, Tuğrul Tolga; Nieland, Thomas J F; Padilla, Frédéric; Demirci, Utkan

    2016-01-06

    A bio-acoustic levitational assembly method for engineering of multilayered, 3D brainlike constructs is presented. Acoustic radiation forces are used to levitate neuroprogenitors derived from human embryonic stem cells in 3D multilayered fibrin tissue constructs. The neuro-progenitor cells are subsequently differentiated in neural cells, resulting in a 3D neuronal construct with inter and intralayer neurite elongations.

  9. Isolation of Promoters and Fragments of Genes Controlling Endosperm Development Without Fertilization in Arabidopsis and Engineering of the Antisense Constructions

    Directory of Open Access Journals (Sweden)

    Grigory A. Gerashchenkov

    2015-06-01

    Full Text Available Apomixis is asexual seed reproduction without both meiosis and fertilization based on the complex developmental processes such as apomeiosis, parthenogenesis and specific endosperm development. This investigation is aimed at engineering of apomixis in Arabidopsis thaliana with sexual seed reproduction. The fragments of known genes of endosperm formation MEA, FIE, FIS2 and gene of apomeiosis DYAD (as control were isolated using Q5 high fidelity DNA polymerase. These gene fragments of interest at the antisense orientation were fused with isolated constitutive and meiosis specific promoters of Arabidopsis at NcoI sites. The fused promoter-gene fragment modules were cloned in pCambia1301 at SalI cites. The engineered constructions will be used for the floral dip transformation of Arabidopsis and down regulation of these genes at engineering of apomixis.

  10. 谈建设工程施工现场火灾特征及扑救措施%Discussion on fire features and firefighting measures in construction field of construction engineering

    Institute of Scientific and Technical Information of China (English)

    王永富

    2016-01-01

    With an introduction of construction field fire hazards of construction engineering, sums up construction engineering construction field fire features, starting from aspects of fire survey, parking location selection and firefighting distribution, the paper describes firefighting measures in construction field of construction engineering, with a view to reduce fire loss at much as possible.%介绍了建设工程施工现场火灾的危险性,总结了建筑工程施工现场火灾的特点,从火情侦察、停车位置选择、灭火力量布置等方面,阐述了建筑工程施工现场火灾扑救措施,以最大限度地降低火灾造成的损失.

  11. Electrical engineering of engineers 2. Alternative current engineering, loci diagrams, transformers, multiphase systems. A lecture and working book for the basic study. 8 ed.; Elektrotechnik fuer Ingenieure 2. Wechselstromtechnik, Ortskurven, Transformator, Mehrphasensysteme. Ein Lehr- und Arbeitsbuch fuer das Grundstudium

    Energy Technology Data Exchange (ETDEWEB)

    Weissgerber, Wilfried

    2013-05-01

    The book under consideration covers the basics and calculation methods of the alternating current technology, the transformer, loci diagrams as well as three-phase systems. The book is dedicated to the students of engineering and natural sciences, electrical engineering, technical informatics and physics at higher institutes of applied sciences, technical colleges, universities and universities of cooperative education.

  12. Engineering-Based Problem Solving in the Middle School: Design and Construction with Simple Machines

    Science.gov (United States)

    English, Lyn D.; Hudson, Peter; Dawes, Les

    2013-01-01

    Incorporating engineering concepts into middle school curriculum is seen as an effective way to improve students' problem-solving skills. A selection of findings is reported from a science, technology, engineering and mathematics (STEM)-based unit in which students in the second year (grade 8) of a three-year longitudinal study explored…

  13. CERL: A History of the U.S. Army Construction Engineering Research Laboratory 1968-1974

    Science.gov (United States)

    1975-01-01

    and equipment per- formance. For many years concrete mattresses with copper-clad steel wire reinforcement have been used by the Corps of Engineers...Engineers. biaxial shock test machine: used for shock and vibration testing of equipment. Built in 1973 , it is one of the largest machines of its

  14. Gendered practices of constructing an engineering identity in a problem-based learning environment

    DEFF Research Database (Denmark)

    Du, Xiangyun

    2006-01-01

    This article examines the learning experiences of engineering students of both genders in a problem-based and project-organized learning environment (PBL) at a Danish university. This study relates an amalgam of theories on learning and gender to the context of engineering education. Based on data...

  15. An engineering assessment of the burning of the combustible fraction of construction and demolition wastes in a redundant brick kiln.

    Science.gov (United States)

    Chang, N B; Lin, K S; Sun, Y P; Wang, H P

    2001-12-01

    This paper confirms both technical feasibility and economic potential via the use of redundant brick kilns as an alternative option for disposal of the combustible fractions of construction and demolition wastes by a three-stage analysis. To assess such an idea, one brick kiln was selected for performing an engineering feasibility study. First of all, field sampling and lab-analyses were carried out to gain a deeper understanding of the physical, chemical, and thermodynamic properties of the combustible fractions of construction and demolition wastes. Kinetic parameters for the oxidation of the combustible fractions of construction and demolition wastes were therefore numerically calculated from the weight loss data obtained through a practice of thermogravimetric analyzer (TGA). Secondly, an engineering assessment for retrofitting the redundant brick kiln was performed based on integrating several new and existing unit operations, consisting of waste storage, shredding, feeding, combustion, flue gas cleaning, and ash removal. Such changes were subject to the operational condition in accordance with the estimated mass and energy balances. Finally, addressing the economic value of energy recovery motivated a renewed interest to convert the combustible fractions of construction and demolition wastes into useful hot water for secondary uses.

  16. An Ethical (Descriptive) Framework for Judgment of Actions and Decisions in the Construction Industry and Engineering-Part I.

    Science.gov (United States)

    Alkhatib, Omar J; Abdou, Alaa

    2017-03-20

    The construction industry is usually characterized as a fragmented system of multiple-organizational entities in which members from different technical backgrounds and moral values join together to develop a particular business or project. The greatest challenge in the construction process for the achievement of a successful practice is the development of an outstanding reputation, which is built on identifying and applying an ethical framework. This framework should reflect a common ethical ground for myriad people involved in this process to survive and compete ethically in today's turbulent construction market. This study establishes a framework for ethical judgment of behavior and actions conducted in the construction process. The framework was primarily developed based on the essential attributes of business management identified in the literature review and subsequently incorporates additional attributes identified to prevent breaches in the construction industry and common ethical values related to professional engineering. The proposed judgment framework is based primarily on the ethical dimension of professional responsibility. The Ethical Judgment Framework consists of descriptive approaches involving technical, professional, administrative, and miscellaneous terms. The framework provides the basis for judging actions as either ethical or unethical. Furthermore, the framework can be implemented as a form of preventive ethics, which would help avoid ethical dilemmas and moral allegations. The framework can be considered a decision-making model to guide actions and improve the ethical reasoning process that would help individuals think through possible implications and consequences of ethical dilemmas in the construction industry.

  17. Use of Adult Stem Cells for Cartilage Tissue Engineering: Current Status and Future Developments

    Directory of Open Access Journals (Sweden)

    Catherine Baugé

    2015-01-01

    Full Text Available Due to their low self-repair ability, cartilage defects that result from joint injury, aging, or osteoarthritis, are the most often irreversible and are a major cause of joint pain and chronic disability. So, in recent years, researchers and surgeons have been working hard to elaborate cartilage repair interventions for patients who suffer from cartilage damage. However, current methods do not perfectly restore hyaline cartilage and may lead to the apparition of fibro- or hypertrophic cartilage. In the next years, the development of new strategies using adult stem cells, in scaffolds, with supplementation of culture medium and/or culture in low oxygen tension should improve the quality of neoformed cartilage. Through these solutions, some of the latest technologies start to bring very promising results in repairing cartilage from traumatic injury or chondropathies. This review discusses the current knowledge about the use of adult stem cells in the context of cartilage tissue engineering and presents clinical trials in progress, as well as in the future, especially in the field of bioprinting stem cells.

  18. Electrical engineering of engineers 1. Direct current engineering and electromagnetic field. A lecture and working book for the basic study. 9. rev. ed.; Elektrotechnik fuer Ingenieure 1. Gleichstromtechnik und Elektromagnetisches Feld. Ein Lehr- und Arbeitsbuch fuer das Grundstudium

    Energy Technology Data Exchange (ETDEWEB)

    Weissgerber, Wilfried

    2013-05-01

    The book under consideration covers the basics and calculation methods of the direct current technology as well as the electromagnetic field. The main topics are: fundamental concepts of physics, direct current technology, electric circuit, network calculation, energy and power, electromagnetic field, electric flow field, electrostatic and magnetic fields, induction, magnetic energy. The book is dedicated to the students of engineering and natural sciences, electrical engineering, technical informatics and physics at higher institutes of applied sciences, technical colleges, universities and universities of cooperative education.

  19. Antibiotic-releasing porous polymethylmethacrylate/gelatin/antibiotic constructs for craniofacial tissue engineering.

    Science.gov (United States)

    Shi, Meng; Kretlow, James D; Spicer, Patrick P; Tabata, Yasuhiko; Demian, Nagi; Wong, Mark E; Kasper, F Kurtis; Mikos, Antonios G

    2011-05-30

    An antibiotic-releasing porous polymethylmethacrylate (PMMA) construct was developed to maintain the bony space and prime the wound site in the initial step of a two-stage regenerative medicine approach toward reconstructing significant bony or composite craniofacial tissue defects. Porous PMMA constructs incorporating gelatin microparticles (GMPs) were fabricated by the sequential assembly of GMPs, the antibiotic colistin, and a clinically used bone cement formulation of PMMA powder and methylmethacrylate liquid. PMMA/gelatin/antibiotic constructs with varying gelatin incorporation and drug content were investigated to elucidate the relationship between material composition and construct properties (porosity and drug release kinetics). The porosity of PMMA/gelatin/antibiotic constructs ranged between 7.6±1.8% and 38.4±1.4% depending on the amount of gelatin incorporated and the drug solution added for gelatin swelling. The constructs released colistin over 10 or 14 days with an average release rate per day above 10 μg/ml. The porosity and in vitro colistin release kinetics of PMMA/gelatin/antibiotic constructs were tuned by varying the material composition and fabrication parameters. This study demonstrates the potential of gelatin-incorporating PMMA constructs as a functional space maintainer for both promoting tissue healing/coverage and addressing local infections, enabling better long-term success of the definitive regenerated tissue construct. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Noninvasive quantification of in vitro osteoblastic differentiation in 3D engineered tissue constructs using spectral ultrasound imaging.

    Science.gov (United States)

    Gudur, Madhu Sudhan Reddy; Rao, Rameshwar R; Peterson, Alexis W; Caldwell, David J; Stegemann, Jan P; Deng, Cheri X

    2014-01-01

    Non-destructive monitoring of engineered tissues is needed for translation of these products from the lab to the clinic. In this study, non-invasive, high resolution spectral ultrasound imaging (SUSI) was used to monitor the differentiation of MC3T3 pre-osteoblasts seeded within collagen hydrogels. SUSI was used to measure the diameter, concentration and acoustic attenuation of scatterers within such constructs cultured in either control or osteogenic medium over 21 days. Conventional biochemical assays were used on parallel samples to determine DNA content and calcium deposition. Construct volume and morphology were accurately imaged using ultrasound. Cell diameter was estimated to be approximately 12.5-15.5 µm using SUSI, which corresponded well to measurements of fluorescently stained cells. The total number of cells per construct assessed by quantitation of DNA content decreased from 5.6±2.4×10(4) at day 1 to 0.9±0.2×10(4) at day 21. SUSI estimation of the equivalent number of acoustic scatters showed a similar decreasing trend, except at day 21 in the osteogenic samples, which showed a marked increase in both scatterer number and acoustic impedance, suggestive of mineral deposition by the differentiating MC3T3 cells. Estimation of calcium content by SUSI was 41.7±11.4 µg/ml, which agreed well with the biochemical measurement of 38.7±16.7 µg/ml. Color coded maps of parameter values were overlaid on B-mode images to show spatiotemporal changes in cell diameter and calcium deposition. This study demonstrates the use of non-destructive ultrasound imaging to provide quantitative information on the number and differentiated state of cells embedded within 3D engineered constructs, and therefore presents a valuable tool for longitudinal monitoring of engineered tissue development.

  1. 3D tissue-engineered construct analysis via conventional high-resolution microcomputed tomography without X-ray contrast.

    Science.gov (United States)

    Voronov, Roman S; VanGordon, Samuel B; Shambaugh, Robert L; Papavassiliou, Dimitrios V; Sikavitsas, Vassilios I

    2013-05-01

    As the field of tissue engineering develops, researchers are faced with a large number of degrees of freedom regarding the choice of material, architecture, seeding, and culturing. To evaluate the effectiveness of a tissue-engineered strategy, histology is typically done by physically slicing and staining a construct (crude, time-consuming, and unreliable). However, due to recent advances in high-resolution biomedical imaging, microcomputed tomography (μCT) has arisen as a quick and effective way to evaluate samples, while preserving their structure in the original state. However, a major barrier for using μCT to do histology has been its inability to differentiate between materials with similar X-ray attenuation. Various contrasting strategies (hardware and chemical staining agents) have been proposed to address this problem, but at a cost of additional complexity and limited access. Instead, here we suggest a strategy for how virtual 3D histology in silico can be conducted using conventional μCT, and we provide an illustrative example from bone tissue engineering. The key to our methodology is an implementation of scaffold surface architecture that is ordered in relation to cells and tissue, in concert with straightforward image-processing techniques, to minimize the reliance on contrasting for material segmentation. In the case study reported, μCT was used to image and segment porous poly(lactic acid) nonwoven fiber mesh scaffolds that were seeded dynamically with mesenchymal stem cells and cultured to produce soft tissue and mineralized tissue in a flow perfusion bioreactor using an osteogenic medium. The methodology presented herein paves a new way for tissue engineers to identify and distinguish components of cell/tissue/scaffold constructs to easily and effectively evaluate the tissue-engineering strategies that generate them.

  2. Accreditation of Engineering Programs: An Evaluation of Current Practices in Malaysia

    Science.gov (United States)

    Said, Suhana Mohd; Chow, Chee-Onn; Mokhtar, N.; Ramli, Rahizar; Ya, Tuan Mohd Yusoff Shah Tuan; Sabri, Mohd Faizul Mohd

    2013-01-01

    The curriculum for undergraduate engineering courses in Malaysia is becoming increasingly structured, following the global trend for quality assurance in engineering education, through accreditation schemes. Generally, the accreditation criteria call for the graduates from engineering programs to demonstrate a range of skills, from technical…

  3. The UAV and the Current and Future Regulatory Construction for Integration into the National Airspace System

    Science.gov (United States)

    2005-07-01

    vehicles had already begun. In fact, a giant step toward wireless control from a separate or remote location was already taken by Nikola Tesla who in...1898 successfully demonstrated a radio control system he called “telautomaton.” 68 Nikola Tesla was a Serbian electrical engineer-inventor and...J. Seifer, Wizard: The Life and Times of Nikola Tesla Biography of a Genius, 377 (1996). 67 See Newcome, supra note 23, at 16-7. 68 Seifer

  4. Tissue engineering approaches for the construction of a completely autologous tendon substitute

    Directory of Open Access Journals (Sweden)

    Bassetto Franco

    2008-01-01

    Full Text Available Tissue engineering is a multidisciplinary field that involves the application of the principles and methods of engineering and life sciences towards i the fundamental understanding of structure-function relationships in normal and pathological mammalian tissues and ii the development of biological substitutes that restore, maintain or improve tissue function. The goal of tissue engineering is to surpass the limitations of conventional treatments based on organ transplantation and biomaterial implantation. The field of tendon tissue engineering is relatively unexplored due to the difficulty in in vitro preservation of tenocyte phenotype. Only recently has mechanobiology allowed us to gain a better understanding of the fundamental role of in vitro mechanical stimuli in maintaining the phenotype of tendinous tissue. This review analyzes the techniques used so far for in vitro regeneration of tendinous tissue.

  5. Streamlining Demand Fulfilment Chain in Construction Projects : The Case of a Pre Engineered Steel Building Manufacturer

    NARCIS (Netherlands)

    Roosmalen, K.; van Weele, A.; Ashayeri, J.

    2010-01-01

    Practical implications – The results of this paper clearly verify the need for mind change among Pre Engineered and Structural Steel Building firms operating in the Middle-East. Supply chain management methods should be used to improve competitiveness.

  6. Technology Transfer Opportunities for the Construction Engineering Community: Materials and Diagnostics.

    Science.gov (United States)

    1986-02-27

    34 .. CC .0 clj 0 C.C. -" C 4)4) 0 C.27 ROOF BLISTER VALVE Charles Korhonen U.S. Army Cold Regions Research and Engineering Laboratory Annually, the Army...7122 (within Illinois). REFERENCES 1. A. Kumar, E. C. Segan, and J. Bukowski , "Ceramic Coated Anodes for Cathodic Protection," Materials Performance...Chief of Engineers. References: (Available from the author) 1. "Roof Moisture Surveys: Yesterday, Today and Tomorrow," by Wayne Tobiasson and Charles

  7. Discussion on risk management of construction engineering project%谈建设工程项目风险管理

    Institute of Scientific and Technical Information of China (English)

    申宝珍

    2011-01-01

    In light of specific condition of construction engineering project, based on the valuation, of risk and proposes feasible risk protection countermeasures, and describes effective and implementation effect check etc, with a view to reduce risk struction engineering project. identification of project risk factors, it carries on risk erisk management methods including the implementation and loss and to realize risk management target of construction engineering project.%针对建设工程项目的具体情况,在对项目风险因素识别的基础上,进行风险评价,进而提出切实有效的风险防范对策,并从风险对策的实施、实施效果的检查等方面阐述了有效风险管理的具体方法,以期最大限度地降低风险,减少损失,实现建设工程项目的风险管理目标。

  8. Dual perfluorocarbon method to noninvasively monitor dissolved oxygen concentration in tissue engineered constructs in vitro and in vivo.

    Science.gov (United States)

    Goh, Fernie; Long, Robert; Simpson, Nicholas; Sambanis, Athanassios

    2011-07-01

    Noninvasive in vivo monitoring of tissue implants provides important correlations between construct function and the observed physiologic effects. As oxygen is a key parameter affecting cell and tissue function, we established a monitoring method that utilizes (19) F nuclear magnetic resonance (NMR) spectroscopy, with perfluorocarbons (PFCs) as oxygen concentration markers, to noninvasively monitor dissolved oxygen concentration (DO) in tissue engineered implants. Specifically, we developed a dual PFC method capable of simultaneously measuring DO within a tissue construct and its surrounding environment, as the latter varies among animals and with physiologic conditions. In vitro studies using an NMR-compatible bioreactor demonstrated the feasibility of this method to monitor the DO within alginate beads containing metabolically active murine insulinoma βTC-tet cells, relative to the DO in the culture medium, under perfusion and static conditions. The DO profiles obtained under static conditions were supported by mathematical simulations of the system. In vivo, the dual PFC method was successful in tracking the oxygenation state of entrapped βTC-tet cells and the surrounding peritoneal DO over 16 days in normal mice. DO measurements correlated well with the extent of cell growth and host cell attachment examined postexplantation. The peritoneal oxygen environment was found to be variable and hypoxic, and significantly lower in the presence of metabolically active cells. The significance of the dual PFC system in providing critical DO measurements for entrapped cells and other tissue constructs, in vitro and in vivo, is discussed. Copyright © 2011 American Institute of Chemical Engineers (AIChE).

  9. Analysis of technical-economic requirements for the construction of a solar power plant on the roof of the business building of the Electrical Engineering Institute 'Nikola Tesla'

    National Research Council Canada - National Science Library

    Grbić Maja; Antić Radoslav; Ponoćko Jelena; Mikulović Jovan; Đurišić Željko

    2014-01-01

    This paper presents an analysis of the technical-economic requirements for the construction of a solar power plant on the roof of the business building of the Electrical Engineering Institute 'Nikola Tesla' in Belgrade...

  10. Current views of health care design and construction: practical implications for safer, cleaner environments.

    Science.gov (United States)

    Bartley, Judene M; Olmsted, Russell N; Haas, Janet

    2010-06-01

    Infection preventionists (IP) play an increasingly important role in preventing health care-associated infection in the physical environment associated with new construction or renovation of health care facilities. The Guidelines for Design and Construction of Hospital and Healthcare Facilities, 2010, formerly known as "AIA Guidelines" was the origin of the "infection control risk assessment" now required by multiple agencies. These Guidelines represent minimum US health care standards and provide guidance on best practices. They recognize that the built environment has a profound affect on health and the natural environment and require that health care facilities be designed to "first, do no harm." This review uses the Guidelines as a blueprint for IPs' role in design and construction, updating familiar concepts to the 2010 edition with special emphasis on IP input into design given its longer range impact on health care-associated infection prevention while linking to safety and sustainability. Section I provides an overview of disease transmission risks from the built environment and related costs, section II presents a broad view of design and master planning, and section III addresses the detailed design strategies for infection prevention specifically addressed in the 2010 Facility Guidelines Institute edition.

  11. Investigating the effects of behavior constructs on academic persistence in engineering, creativity and risk-taking

    Science.gov (United States)

    Deanes, Viveca K.

    Increasingly over the last decade, engineering colleges across this nation have conducted research to identify factors that will help them better predict students' academic persistence in engineering. While initial efforts were aimed at predicting those who would graduate, recent efforts have been directed toward predicting who will persist to the second year, as it has been found that a substantial percentage of those who leave engineering do so during their first year. Prior research investigated the predictability of academic persistence using academic credentials such as grade point averages and SAT scores. However, recent research on academic persistence in engineering has suggested differences in students' behavior and students' levels of dissonance-induced stress, rather than differences in academic credentials, may distinguish persisters from non-persisters. One aspect of an individual's behavior, compliance, and behavior-related stress, referred to as dissonance-induced stress, are proposed to have an effect on academic persistence. Research shows compliance (or conformity) is diametrically opposed to creativity, which is essential to leadership and innovation in engineering. A similar relationship is likely to exist between compliance and risk-taking. This research investigated whether behavior and dissonance-induced stress are good predictors of academic persistence in engineering. This research also investigated relationships between behavior, creativity, and risk-taking. Students who were enrolled in a first-year Fundamentals in Engineering course (ENGR 112) were the subjects in this research. The Style Analysis Instrument was used to collect data regarding students' behavioral orientations. The Style Analysis Instrument provides both natural and adapted measures in four dimensions of human behavior: dominance, influence, steadiness, and compliance. The Creativity and Risk-Taking Instrument was used to collect data regarding students' creativity and

  12. Discussion on Teaching Methods of Engineering Construction and Management for Undergraduate%工程施工管理课程教学方法探讨

    Institute of Scientific and Technical Information of China (English)

    蒋建平

    2011-01-01

    Based on the characteristics of engineering construction and management and the teaching practics and experience, this paper discussed the teaching methods of engineering construction and management for undergraduate.%本文基于工程施工管理课程的特点和教学体会,对工程施工管理课程的教学方法进行了探讨.

  13. Fuzzy Optimization of Construction Engineering Project Schedule Based on Critical Chain Management

    Directory of Open Access Journals (Sweden)

    Jianbing LIU

    2013-07-01

    Full Text Available Critical chain management was the very important theory innovation in the development of construction project schedule management field in recent years. Compared with the traditional methods of construction project schedule management, the methods of critical chain management considered resource constraints into construction project schedule management, the construction project cycle was shortened and the efficiency was enhanced by using the dynamic thinking and circulation pattern to manage whole project. In view of the progress of critical chain management of the article, fuzzy theory  was used to calculate and optimize the buffer zone sizes with the determination of the buffer size of  the existing resources in certain critical chain management so as to shorten the cycle..

  14. 试论建筑工程进度管理的思路%Discussion on the idea of construction engineering schedule management

    Institute of Scientific and Technical Information of China (English)

    赵美玲

    2015-01-01

    Through the analysis on the factors influence of construction engineering schedule,from resources supply in construction,schedule and plan adjustment,safety management,construction organization and other angle analyzed the idea of construction engineering schedule manage-ment,to strengthen the management of construction engineering schedule,so as to realize the balance of cycle and cost.%通过分析影响建筑工程进度的因素,从施工所需资源供给、进度计划调整、安全管理、施工组织等角度分析了建筑工程进度管理的思路,以加强对建筑施工进度的管理,从而实现周期和成本之间的平衡。

  15. [Cell engineering in nephrology: The current state and prospectives from the point of view of military medicine].

    Science.gov (United States)

    Bel'skih, A N; Golota, A S; Krassii, A B; Nagibovich, O A

    2015-09-01

    This article is dedicated to the current state and prospectives of cell engineering in nephrology from the point of view of military medicine. The review is based on publications from January 1, 2014, to June 1, 2015, and consists of two parts. In the first part the main directions of the cell engineering development are mentioned. The only two clinical trials existed in the field are discussed in more detail. The second part deals with prospectives of cell engineering in nephrology. It is shown that currently this field is in the stage of preclinical experimentation. Of the two known clinical trials the first has failed to demonstrate any effectiveness of cell engineering, the second--will be completed only at the end of 2016. Also, the review notes an extraordinary cost of cell engineering experiments in nephrology. The analysis of publications allows to come to a conclusion that the future progress in prevention and treatment of acute kidney injury could go not in the direction of cell engineering but rather non-cell technologies. One of. the practical consequence of such a conclusion is a necessity to continue the improvement of already existing methods of machine renal replacement therapy.

  16. Skin equivalent tissue-engineered construct: co-cultured fibroblasts/ keratinocytes on 3D matrices of sericin hope cocoons.

    Science.gov (United States)

    Nayak, Sunita; Dey, Sancharika; Kundu, Subhas C

    2013-01-01

    The development of effective and alternative tissue-engineered skin replacements to autografts, allografts and xenografts has became a clinical requirement due to the problems related to source of donor tissue and the perceived risk of disease transmission. In the present study 3D tissue engineered construct of sericin is developed using co-culture of keratinocytes on the upper surface of the fabricated matrices and with fibroblasts on lower surface. Sericin is obtained from "Sericin Hope" silkworm of Bombyx mori mutant and is extracted from cocoons by autoclave. Porous sericin matrices are prepared by freeze dried method using genipin as crosslinker. The matrices are characterized biochemically and biophysically. The cell proliferation and viability of co-cultured fibroblasts and keratinocytes on matrices for at least 28 days are observed by live/dead assay, Alamar blue assay, and by dual fluorescent staining. The growth of the fibroblasts and keratinocytes in co-culture is correlated with the expression level of TGF-β, b-FGF and IL-8 in the cultured supernatants by enzyme-linked immunosorbent assay. The histological analysis further demonstrates a multi-layered stratified epidermal layer of uninhibited keratinocytes in co-cultured constructs. Presence of involucrin, collagen IV and the fibroblast surface protein in immuno-histochemical stained sections of co-cultured matrices indicates the significance of paracrine signaling between keratinocytes and fibroblasts in the expression of extracellular matrix protein for dermal repair. No significant amount of pro inflammatory cytokines (TNF-α, IL-1β and nitric oxide) production are evidenced when macrophages grown on the sericin matrices. The results all together depict the potentiality of sericin 3D matrices as skin equivalent tissue engineered construct in wound repair.

  17. A Analysis on Macro Control Measures for Project Management of Construction Engineering%建筑工程项目管理宏观控制措施

    Institute of Scientific and Technical Information of China (English)

    王晓磊

    2015-01-01

    Construction engineering project management is a systematical,comprehensive and complex process.It is necessary to establish a construction engineering project management body of knowledge,cultivate multi-competent personnel who are proficient in engineering technology and management and develop advanced intelligent construction engineering mechanical machinery.Besides,construction enterprises shall enhance the management and control measures for construction engineering projectal,establish scientific,standardized,practical and programmed safety and quality system,so as to ensure the achievement of the goal of construction engineering project management.%建筑工程项目管理是一个系统、全面且复杂的过程. 应建立成熟完善的建筑工程项目管理知识体系,培养工程技术与管理相结合的复合型人才,研发先进的建筑工程智能化机械设备. 同时建筑企业必须强化建筑工程项目的管控措施,建立科学、规范、实用及程序化的安全质量体系,以保证建筑工程项目管理目标实现.

  18. Engineering geological and geophysical investigations for road construction in the municipality of Sisimiut, West Greenland

    DEFF Research Database (Denmark)

    2007-01-01

    and permafrost distribution, as well as engineering geological and geotechnical investigations conducted. We present data from two soil temperature stations, and show that the recent climatic warming has resulted in changes in the state of the permafrost. Furthermore, we present a geological type section based...... on engineering geological investigations in the Sisimiut area. Geophysical investigations show that presence of permafrost is widespread, and our results indicate that the vertical thickness of the permafrost may reach 20 m. Further climate warming in the near future will impose high demands on design...

  19. Introduction to Quality Management of the Construction Engineering%浅谈建筑工程质量管理

    Institute of Scientific and Technical Information of China (English)

    虞文友; 厉龙进

    2014-01-01

    This article discusses the establishment of the quality management system, the basis of the engineering quality inspection, total quality management as wel as the factors influencing the project quality, so as to provide certain reference for quality management of the construction eng- ineering.%本文论述了质量管理体系的建立、工程质量检查的依据、全面质量管理以及影响工程质量的因素,以期为建筑工程质量管理的提供一定的参考建议。

  20. Value engineering the construction of long tunnels in the dolomites of northern Illinois, United States of America

    Energy Technology Data Exchange (ETDEWEB)

    Laughton, Christopher; /Fermilab

    2000-01-01

    Fermi National Accelerator Laboratory (Fermilab), a high-energy physics laboratory operated by the Universities Research Association for the US Department of Energy, is developing plans for the construction of accelerator tunnels. The accelerator designs vary as a function of particles accelerated, technologies used and energies targeted. However, all accelerators require the excavation of long tunnels, up to 700 km in length, and tunnel costs represent a major portion of project budgets. This paper documents the findings of two studies undertaken to identify tunnel cost-drivers and outlines steps taken to initiate the ''value engineering'' of the tunnels.

  1. Engineering change management report 2012: Survey results on causes and effects, current practice, problems, and strategies in Brazil

    DEFF Research Database (Denmark)

    Chucholowski, Nepomuk; Langer, Stefan; Ferreira, Marcelo Gitirana Gomes

    management of engineering changes is a crucial precondition for Brazilian companies to successfully compete not only on the fast growing Brazilian market, but also on the world market which becomes more interesting due to the rising industrial power of Brazil. To achieve improvements in engineering change...... management practice, industry and universities need to work together. In this report the main findings of our study on Engineering Change Management (ECM) in Brazilian companies are presented, which indicate possible solution strategies and further research needs. Our survey aimed on the investigation...... of current practice, the biggest challenges and potential strategies of engineering change management. A total of 55 Brazilian companies from a broad range of industry sectors and company sizes participated from December 2011 until January 2012 in the survey which was elaborated and conducted by members...

  2. Dual-frequency Eddy Current Non-destructive Detection of Fatigue Cracks in Compressor Discs of Aero Engines

    Directory of Open Access Journals (Sweden)

    B. Sasi

    2004-10-01

    Full Text Available Eddy current non-destructive testing is used to inspect the critical aircraft components. The shortcomings of the inspection method identified, based on a few accidents, necessitatethe development of high sensitive and reliable testing procedures for inspecting the critical safety related aircraft components. This paper discusses a dual-frequency eddy current testingprocedure developed for inspection of compressor discs of aero engines for detecting fatigue cracks with high sensitivity and reliability. This procedure is capable of detecting fatigue crackssmaller than 2 mm in comparison to 4 mm cracks that can be detected with the currently practiced eddy current testing procedure.

  3. Data-driven technology for engineering systems health management design approach, feature construction, fault diagnosis, prognosis, fusion and decisions

    CERN Document Server

    Niu, Gang

    2017-01-01

    This book introduces condition-based maintenance (CBM)/data-driven prognostics and health management (PHM) in detail, first explaining the PHM design approach from a systems engineering perspective, then summarizing and elaborating on the data-driven methodology for feature construction, as well as feature-based fault diagnosis and prognosis. The book includes a wealth of illustrations and tables to help explain the algorithms, as well as practical examples showing how to use this tool to solve situations for which analytic solutions are poorly suited. It equips readers to apply the concepts discussed in order to analyze and solve a variety of problems in PHM system design, feature construction, fault diagnosis and prognosis.

  4. New Media, Old Images: Constructing Online Representations of Women and Men in Science, Engineering and Technology

    Science.gov (United States)

    Mendick, Heather; Moreau, Marie-Pierre

    2013-01-01

    This paper looks at online representations of women and men in science, engineering and technology. We show that these representations largely re/produce dominant gender discourses. We then focus on the question: How are gender cliched images re/produced online? Drawing on a discursive analysis of data from six interviews with web authors, we…

  5. An overview of methods for the in vivo evaluation of tissue-engineered skin constructs

    NARCIS (Netherlands)

    Lammers, G.; Verhaegen, P.D.; Ulrich, M.M.; Schalkwijk, J.; Middelkoop, E.; Weiland, D.; Nillesen, S.T.M.; Kuppevelt, A.H.M.S.M. van; Daamen, W.F.

    2011-01-01

    Cutaneous wounding often leads to contraction and scarring, which may result in a range of functional, cosmetic, and psychological complications. Tissue-engineered skin substitutes are being developed to enhance restoration of the skin and improve the quality of wound healing. The aim of this review

  6. Engineering metabolic pathways in Escherichia coli for constructing a "microbial chassis" for biochemical production.

    Science.gov (United States)

    Matsumoto, Takuya; Tanaka, Tsutomu; Kondo, Akihiko

    2017-05-04

    The present work reviews literature describing the re-design of the metabolic pathways of a microbial host using sophisticated genetic tools, yielding strains for producing value-added chemicals including fuels, building-block chemicals, pharmaceuticals, and derivatives. This work employed Escherichia coli, a well-studied microorganism that has been successfully engineered to produce various chemicals. E. coli has several advantages compared with other microorganisms, including robustness, and handling. To achieve efficient productivities of target compounds, an engineered E. coli should accumulate metabolic precursors of target compounds. Multiple researchers have reported the use of pathway engineering to generate strains capable of accumulating various metabolic precursors, including pyruvate, acetyl-CoA, malonyl-CoA, mevalonate and shikimate. The aim of this review provides a promising guideline for designing E. coli strains capable of producing a variety of useful chemicals. Herein, the present work reviews their common and unique strategies, treating metabolically engineered E. coli as a "microbial chassis". Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Application of Composite Structures in Bridge Engineering. Problems of Construction Process and Strength Analysis

    OpenAIRE

    Flaga Kazimierz; Furtak Kazimierz

    2015-01-01

    Steel-concrete composite structures have been used in bridge engineering from decades. This is due to rational utilisation of the strength properties of the two materials. At the same time, the reinforced concrete (or prestressed) deck slab is more favourable than the orthotropic steel plate used in steel bridges (higher mass, better vibration damping, longer life).

  8. Mechanical stretching for tissue engineering: two-dimensional and three-dimensional constructs.

    Science.gov (United States)

    Riehl, Brandon D; Park, Jae-Hong; Kwon, Il Keun; Lim, Jung Yul

    2012-08-01

    Mechanical cell stretching may be an attractive strategy for the tissue engineering of mechanically functional tissues. It has been demonstrated that cell growth and differentiation can be guided by cell stretch with minimal help from soluble factors and engineered tissues that are mechanically stretched in bioreactors may have superior organization, functionality, and strength compared with unstretched counterparts. This review explores recent studies on cell stretching in both two-dimensional (2D) and three-dimensional (3D) setups focusing on the applications of stretch stimulation as a tool for controlling cell orientation, growth, gene expression, lineage commitment, and differentiation and for achieving successful tissue engineering of mechanically functional tissues, including cardiac, muscle, vasculature, ligament, tendon, bone, and so on. Custom stretching devices and lab-specific mechanical bioreactors are described with a discussion on capabilities and limitations. While stretch mechanotransduction pathways have been examined using 2D stretch, studying such pathways in physiologically relevant 3D environments may be required to understand how cells direct tissue development under stretch. Cell stretch study using 3D milieus may also help to develop tissue-specific stretch regimens optimized with biochemical feedback, which once developed will provide optimal tissue engineering protocols.

  9. Mechanical Stretching for Tissue Engineering: Two-Dimensional and Three-Dimensional Constructs

    Science.gov (United States)

    Riehl, Brandon D.; Park, Jae-Hong; Kwon, Il Keun

    2012-01-01

    Mechanical cell stretching may be an attractive strategy for the tissue engineering of mechanically functional tissues. It has been demonstrated that cell growth and differentiation can be guided by cell stretch with minimal help from soluble factors and engineered tissues that are mechanically stretched in bioreactors may have superior organization, functionality, and strength compared with unstretched counterparts. This review explores recent studies on cell stretching in both two-dimensional (2D) and three-dimensional (3D) setups focusing on the applications of stretch stimulation as a tool for controlling cell orientation, growth, gene expression, lineage commitment, and differentiation and for achieving successful tissue engineering of mechanically functional tissues, including cardiac, muscle, vasculature, ligament, tendon, bone, and so on. Custom stretching devices and lab-specific mechanical bioreactors are described with a discussion on capabilities and limitations. While stretch mechanotransduction pathways have been examined using 2D stretch, studying such pathways in physiologically relevant 3D environments may be required to understand how cells direct tissue development under stretch. Cell stretch study using 3D milieus may also help to develop tissue-specific stretch regimens optimized with biochemical feedback, which once developed will provide optimal tissue engineering protocols. PMID:22335794

  10. Auto-Erecting Virtual Office Walls: Constructing a Virtual Office for Global Software Engineers

    NARCIS (Netherlands)

    Van Gameren, B.J.A.

    2014-01-01

    Due to the globalization of business and the rising popularity of working from home, global software engineering is becoming increasingly common. In such a distributed environment, team members no longer share a physical work environment and should be provided with information they need to

  11. The construction of an engineered bacterium to remove cadmium from wastewater.

    Science.gov (United States)

    Chang, S; Shu, H

    2014-01-01

    The removal of cadmium (Cd) from wastewater before it is released from factories is important for protecting human health. Although some researchers have developed engineered bacteria, the resistance of these engineered bacteria to Cd have not been improved. In this study, two key genes involved in glutathione synthesis (gshA and gshB), a serine acetyltransferase gene (cysE), a Thlaspi caerulescens phytochelatin synthase gene (TcPCS1), and a heavy metal ATPase gene (TcHMA3) were transformed into Escherichia coli BL21. The resistance of the engineered bacterium to Cd was significantly greater than that of the initial bacterium and the Cd accumulation in the engineered bacterium was much higher than in the initial bacterium. In addition, the Cd resistance of the bacteria harboring gshB, gshA, cysE, and TcPCS1 was higher than that of the bacteria harboring gshA, cysE, and TcPCS1. This finding demonstrated that gshB played an important role in glutathione synthesis and that the reaction catalyzed by glutathione synthase was the limiting step for producing phytochelatins. Furthermore, TcPCS1 had a greater specificity and a higher capacity for removing Cd than SpPCS1, and TcHMA3 not only played a role in T. caerulescens but also functioned in E. coli.

  12. Auto-Erecting Virtual Office Walls: Constructing a Virtual Office for Global Software Engineers

    NARCIS (Netherlands)

    Van Gameren, B.J.A.

    2014-01-01

    Due to the globalization of business and the rising popularity of working from home, global software engineering is becoming increasingly common. In such a distributed environment, team members no longer share a physical work environment and should be provided with information they need to collabora

  13. Engineering geological and geophysical investigations for road construction in the municipality of Sisimiut, West Greenland

    DEFF Research Database (Denmark)

    2007-01-01

    on engineering geological investigations in the Sisimiut area. Geophysical investigations show that presence of permafrost is widespread, and our results indicate that the vertical thickness of the permafrost may reach 20 m. Further climate warming in the near future will impose high demands on design...

  14. New Media, Old Images: Constructing Online Representations of Women and Men in Science, Engineering and Technology

    Science.gov (United States)

    Mendick, Heather; Moreau, Marie-Pierre

    2013-01-01

    This paper looks at online representations of women and men in science, engineering and technology. We show that these representations largely re/produce dominant gender discourses. We then focus on the question: How are gender cliched images re/produced online? Drawing on a discursive analysis of data from six interviews with web authors, we…

  15. The current state of engineered nanomaterials in consumer goods and waste streams: the need to develop nanoproperty-quantifiable sensors for monitoring engineered nanomaterials.

    Science.gov (United States)

    Wise, Kelsey; Brasuel, Murphy

    2011-07-01

    As nanomaterials are harnessed for medicine and other technological advances, an understanding of the toxicology of these new materials is required to inform our use. This toxicological knowledge will be required to establish the medical and environmental regulations required to protect consumers and those involved in nanomaterial manufacturing. Nanoparticles of titanium oxide, carbon nanotubes, semiconductor quantum dots, gold, and silver represent a high percentage of the nanotechnology currently available or currently poised to reach consumers. For these nanoparticles, this review aims to identify current applications, the current methods used for characterization and quantification, current environmental concentrations (if known), and an introduction to the toxicology research. Continued development of analytical tools for the characterization and quantification of nanomaterials in complex environmental and biological samples will be required for our understanding of the toxicology and environmental impact of nanomaterials. Nearly all materials exhibit toxicity at a high enough concentration. Robust, rapid, and cost effective analytical techniques will be required to determine current background levels of anthropogenic, accidental, and engineered nanoparticles in air, water, and soil. The impact of the growing number of engineered nanoparticles used in consumer goods and medical applications can then be estimated. This will allow toxicological profiles relevant to the demonstrated or predicted environmental concentrations to be determined.

  16. The current state of engineered nanomaterials in consumer goods and waste streams: the need to develop nanoproperty-quantifiable sensors for monitoring engineered nanomaterials

    Directory of Open Access Journals (Sweden)

    Wise K

    2011-07-01

    Full Text Available Kelsey Wise, Murphy BrasuelDepartment of Chemistry and Biochemistry, Colorado College, Colorado Springs, CO, USAAbstract: As nanomaterials are harnessed for medicine and other technological advances, an understanding of the toxicology of these new materials is required to inform our use. This toxicological knowledge will be required to establish the medical and environmental regulations required to protect consumers and those involved in nanomaterial manufacturing. Nanoparticles of titanium oxide, carbon nanotubes, semiconductor quantum dots, gold, and silver represent a high percentage of the nanotechnology currently available or currently poised to reach consumers. For these nanoparticles, this review aims to identify current applications, the current methods used for characterization and quantification, current environmental concentrations (if known, and an introduction to the toxicology research. Continued development of analytical tools for the characterization and quantification of nanomaterials in complex environmental and biological samples will be required for our understanding of the toxicology and environmental impact of nanomaterials. Nearly all materials exhibit toxicity at a high enough concentration. Robust, rapid, and cost effective analytical techniques will be required to determine current background levels of anthropogenic, accidental, and engineered nanoparticles in air, water, and soil. The impact of the growing number of engineered nanoparticles used in consumer goods and medical applications can then be estimated. This will allow toxicological profiles relevant to the demonstrated or predicted environmental concentrations to be determined.Keywords: titanium dioxide nanoparticles, carbon nanotubes, semiconductor quantum dots, gold nanoparticles, silver nanoparticles, nanoparticles environmental concentrations

  17. Evaluation of stray current corrosion resistance of concrete in metro construction

    Institute of Scientific and Technical Information of China (English)

    Shucai YANG; Xu YANG

    2008-01-01

    By simulation tests of concrete specimens in saturated Ca(OH)2 solution and seawater, and based on micro mechanism analysis, this paper evaluates the stray current corrosion resistance of concrete specimens of dif-ferent mixture ratios, and reaches a conclusion that the capability to resist stray current corrosion of optimally designed concrete mixed with good-quality fly ash and powdered slag is increased by over 5 times more than the reference concrete with the same water to binder ratio, and the service life of such kind of concrete meets the basic requirement of a metro project.

  18. YeastFab: the design and construction of standard biological parts for metabolic engineering in Saccharomyces cerevisiae.

    Science.gov (United States)

    Guo, Yakun; Dong, Junkai; Zhou, Tong; Auxillos, Jamie; Li, Tianyi; Zhang, Weimin; Wang, Lihui; Shen, Yue; Luo, Yisha; Zheng, Yijing; Lin, Jiwei; Chen, Guo-Qiang; Wu, Qingyu; Cai, Yizhi; Dai, Junbiao

    2015-07-27

    It is a routine task in metabolic engineering to introduce multicomponent pathways into a heterologous host for production of metabolites. However, this process sometimes may take weeks to months due to the lack of standardized genetic tools. Here, we present a method for the design and construction of biological parts based on the native genes and regulatory elements in Saccharomyces cerevisiae. We have developed highly efficient protocols (termed YeastFab Assembly) to synthesize these genetic elements as standardized biological parts, which can be used to assemble transcriptional units in a single-tube reaction. In addition, standardized characterization assays are developed using reporter constructs to calibrate the function of promoters. Furthermore, the assembled transcription units can be either assayed individually or applied to construct multi-gene metabolic pathways, which targets a genomic locus or a receiving plasmid effectively, through a simple in vitro reaction. Finally, using β-carotene biosynthesis pathway as an example, we demonstrate that our method allows us not only to construct and test a metabolic pathway in several days, but also to optimize the production through combinatorial assembly of a pathway using hundreds of regulatory biological parts.

  19. Engineering fibrin-based tissue constructs from myofibroblasts and application of constraints and strain to induce cell and collagen reorganization.

    Science.gov (United States)

    de Jonge, Nicky; Baaijens, Frank P T; Bouten, Carlijn V C

    2013-10-28

    Collagen content and organization in developing collagenous tissues can be influenced by local tissue strains and tissue constraint. Tissue engineers aim to use these principles to create tissues with predefined collagen architectures. A full understanding of the exact underlying processes of collagen remodeling to control the final tissue architecture, however, is lacking. In particular, little is known about the (re)orientation of collagen fibers in response to changes in tissue mechanical loading conditions. We developed an in vitro model system, consisting of biaxially-constrained myofibroblast-seeded fibrin constructs, to further elucidate collagen (re)orientation in response to i) reverting biaxial to uniaxial static loading conditions and ii) cyclic uniaxial loading of the biaxially-constrained constructs before and after a change in loading direction, with use of the Flexcell FX4000T loading device. Time-lapse confocal imaging is used to visualize collagen (re)orientation in a nondestructive manner. Cell and collagen organization in the constructs can be visualized in real-time, and an internal reference system allows us to relocate cells and collagen structures for time-lapse analysis. Various aspects of the model system can be adjusted, like cell source or use of healthy and diseased cells. Additives can be used to further elucidate mechanisms underlying collagen remodeling, by for example adding MMPs or blocking integrins. Shape and size of the construct can be easily adapted to specific needs, resulting in a highly tunable model system to study cell and collagen (re)organization.

  20. Design and construction of a Faraday cup for measurement of small electronic currents

    Science.gov (United States)

    Veyssiere, A.

    1985-01-01

    The design of a device to measure and integrate very small currents generated by the impact of a charged particle beam upon a Faraday cut is described. The main component is a graphite block capable of stopping practically all the incident changes. The associated electronic apparatus required to measure better than 10/13 ampere with a precision of 10/0 is described.

  1. Effects of Globalisation on Higher Engineering Education in Germany--Current and Future Demands

    Science.gov (United States)

    Morace, Christophe; May, Dominik; Terkowsky, Claudius; Reynet, Olivier

    2017-01-01

    Germany is well known around the world for the strength of its economy, its industry and for the "German model" for higher engineering education based on developing technological skills at a very high level. In this article, we firstly describe the former and present model of engineering education in Germany in a context of the…

  2. Automatic Construction of Lightweight Domain Ontologies for Chemical Engineering Risk Management

    CERN Document Server

    Wong, Wilson; Liaw, Saujoe; Balliu, Nicoletta; Wu, Hongwei; Tade, Moses

    2008-01-01

    The need for domain ontologies in mission critical applications such as risk management and hazard identification is becoming more and more pressing. Most research on ontology learning conducted in the academia remains unrealistic for real-world applications. One of the main problems is the dependence on non-incremental, rare knowledge and textual resources, and manually-crafted patterns and rules. This paper reports work in progress aiming to address such undesirable dependencies during ontology construction. Initial experiments using a working prototype of the system revealed promising potentials in automatically constructing high-quality domain ontologies using real-world texts.

  3. Role of Plants in a Constructed Wetland: Current and New Perspectives

    Directory of Open Access Journals (Sweden)

    Amit Gross

    2013-04-01

    Full Text Available The role of plants in the treatment of effluents by constructed wetland (CW systems is under debate. Here, we review ways in which plants can affect CW processes and suggest two novel functions for plants in CWs. The first is salt phytoremediation by halophytes. We have strong evidence that halophytic plants can reduce wastewater salinity by accumulating salts in their tissues. Our studies have shown that Bassia indica, a halophytic annual, is capable of salt phytoremediation, accumulating sodium to up to 10% of its dry weight. The second novel use of plants in CWs is as phytoindicators of water quality. We demonstrate that accumulation of H2O2, a marker for plant stress, is reduced in the in successive treatment stages, where water quality is improved. It is recommended that monitoring and management of CWs consider the potential of plants as phytoremediators and phytoindicators.

  4. A critical review of engineered nanomaterial release data: Are current data useful for material flow modeling?

    Science.gov (United States)

    Caballero-Guzman, Alejandro; Nowack, Bernd

    2016-06-01

    Material flow analysis (MFA) is a useful tool to predict the flows of engineered nanomaterials (ENM) to the environment. The quantification of release factors is a crucial part of MFA modeling. In the last years an increasing amount of literature on release of ENM from materials and products has been published. The purpose of this review is to analyze the strategies implemented by MFA models to include these release data, in particular to derive transfer coefficients (TC). Our scope was focused on those articles that analyzed the release from applications readily available in the market in settings that resemble average use conditions. Current MFA studies rely to a large extent on extrapolations, authors' assumptions, expert opinions and other informal sources of data to parameterize the models. We were able to qualitatively assess the following aspects of the release literature: (i) the initial characterization of ENM provided, (ii) quantitative information on the mass of ENM released and its characterization, (iii) description of transformation reactions and (iv) assessment of the factors determining release. Although the literature on ENM release is growing, coverage of exposure scenarios is still limited; only 20% of the ENMs used industrially and 36% of the product categories involved have been investigated in release studies and only few relevant release scenarios have been described. Furthermore, the information provided is rather incomplete concerning descriptions and characterizations of ENMs and the released materials. Our results show that both the development of methods to define the TCs and of protocols to enhance assessment of ENM release from nano-applications will contribute to increase the exploitability of the data provided for MFA models. The suggestions we provide in this article will likely contribute to an improved exposure modeling by providing ENM release estimates closer to reality.

  5. The 3D printing of gelatin methacrylamide cell-laden tissue-engineered constructs with high cell viability.

    Science.gov (United States)

    Billiet, Thomas; Gevaert, Elien; De Schryver, Thomas; Cornelissen, Maria; Dubruel, Peter

    2014-01-01

    In the present study, we report on the combined efforts of material chemistry, engineering and biology as a systemic approach for the fabrication of high viability 3D printed macroporous gelatin methacrylamide constructs. First, we propose the use and optimization of VA-086 as a photo-initiator with enhanced biocompatibility compared to the conventional Irgacure 2959. Second, a parametric study on the printing of gelatins was performed in order to characterize and compare construct architectures. Hereby, the influence of the hydrogel building block concentration, the printing temperature, the printing pressure, the printing speed, and the cell density were analyzed in depth. As a result, scaffolds could be designed having a 100% interconnected pore network in the gelatin concentration range of 10-20 w/v%. In the last part, the fabrication of cell-laden scaffolds was studied, whereby the application for tissue engineering was tested by encapsulation of the hepatocarcinoma cell line (HepG2). Printing pressure and needle shape was revealed to impact the overall cell viability. Mechanically stable cell-laden gelatin methacrylamide scaffolds with high cell viability (>97%) could be printed.

  6. Ex vivo non-invasive assessment of cell viability and proliferation in bio-engineered whole organ constructs.

    Science.gov (United States)

    Ren, Xi; Tapias, Luis F; Jank, Bernhard J; Mathisen, Douglas J; Lanuti, Michael; Ott, Harald C

    2015-06-01

    Decellularized organ scaffolds allow whole organ regeneration and study of cell behavior in three-dimensional culture conditions. Cell viability within the bio-engineered organ constructs is an essential parameter reflecting the performance of participating cells during long-term ex vivo culture, and is a prerequisite for further functional performance. Resazurin-based redox metabolic assays have been used to monitor cell viability in both two- and three-dimensional cell cultures. Here we developed a method for monitoring cell viability and proliferation in bio-engineered organ constructs using a resazurin perfusion assay. This method allows non-invasive, repetitive and rapid estimation of viable cell numbers during long-term ex vivo culture. As a proof-of-principle, we assessed the performance of two different endothelial sources and the impact of different perfusion programs on endothelial viability after re-endothelialization of decellularized lung scaffolds. The resazurin-based perfusion assay revealed changes in endothelial viability and proliferation during long-term ex vivo culture, which was consistent with histological assessment at different time points. Finally, we showed that this method could be used for assessment of proliferation and cytotoxicity after pharmacological treatment on a three-dimensional non-small cell lung cancer culture model.

  7. Engineering at SLAC: Designing and constructing experimental devices for the Stanford Synchrotron Radiation Lightsource - Final Paper

    Energy Technology Data Exchange (ETDEWEB)

    Djang, Austin [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-22

    Thanks to the versatility of the beam lines at SSRL, research there is varied and benefits multiple fields. Each experiment requires a particular set of experiment equipment, which in turns requires its own particular assembly. As such, new engineering challenges arise from each new experiment. My role as an engineering intern has been to help solve these challenges, by designing and assembling experimental devices. My first project was to design a heated sample holder, which will be used to investigate the effect of temperature on a sample's x-ray diffraction pattern. My second project was to help set up an imaging test, which involved designing a cooled grating holder and assembling multiple positioning stages. My third project was designing a 3D-printed pencil holder for the SSRL workstations.

  8. Constructing Employability Indicators for Enhancing the Effectiveness of Engineering Education for the Solar Industry

    Directory of Open Access Journals (Sweden)

    Chin-Guo Kuo

    2014-01-01

    Full Text Available The aim of this research is to establish a set of employability indicators that capture the competency requirements and performance expectations that solar energy enterprises have of their employees. In the qualitative component of the study, 12 administrators and 32 engineers in the industry were interviewed, and meetings with focus groups were conducted to formulate a questionnaire for a survey of Taiwanese solar energy companies for the confirmation and prioritisation of the employability indicators. On the basis of the results of the quantitative component, an interpretational model relating competence, job performance, working attitude, and employability for solar corporation recruitment and training purposes as well as for school curricular development was developed. The interpretation model formulated effectively interprets the relationship between solar enterprises’ expectations and students’ employability. The research contributes a framework for the selection and cultivation of talent, as well as providing a basis for fundamental development of the solar engineering curriculum.

  9. Heuristic approach for risk assessment modeling: EPCCM application (Engineer Procure Construct Contract Management

    Directory of Open Access Journals (Sweden)

    Ali F. Bakr

    2012-12-01

    Finally, EPCCM; modeling system is created to assist contract administrators, to diminish time, effort, wading back and forth between construction cases and developed projects. The result is a more efficient and proactive contract management environment by providing database for lessons learned in addition to tracking ongoing projects contractual risks, and consequently for issuing relevant decisions and activity plans.

  10. National Ignition Facility start-up/operations engineering and special equipment construction health and safety plan

    Energy Technology Data Exchange (ETDEWEB)

    Huddleston, P C

    1998-05-08

    This document sets forth the responsibilities, interfaces, guidelines, rules, policy, and regulations for all workers involved in the S/O and SE construction, installation, and acceptance testing. This document is enforced from the first day that S/O and SE workers set foot on the NIF construction site until the end of the Project at Critical Decision 4. This document is applicable only to site activities, which are defined as those that occur within the perimeter of the fenced-off NIF construction zone and the Target Chamber Assembly Area (Helipad). The associated Special Equipment laydown and construction support areas listed in Appendix B are not under this plan; their safety provisions are discussed in the Appendix. Prototype and other support activities, such as the Amplifier Laboratory and Frame Assembly Unit assembly area, are not included in this plan. After completion of the Operational Readiness Review, the Facility Safety Procedure, Operational Safety Requirements, and Operational Safety Procedures are the governing safety documents for the operating facility. The S/O and SE project elements are required to implement measures that create a universal awareness of and promote safe job practices at the site. This includes all Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory, Sandia National Laboratories, University of Rochester, supplement labor organization, and subcontractor employees; visitors; and guests serving the S/O and SE effort.

  11. National Ignition Facility start-up/operations engineering and special equipment construction health and safety plan

    Energy Technology Data Exchange (ETDEWEB)

    Huddleston, P C

    1998-05-08

    This document sets forth the responsibilities, interfaces, guidelines, rules, policy, and regulations for all workers involved in the S/O and SE construction, installation, and acceptance testing. This document is enforced from the first day that S/O and SE workers set foot on the NIF construction site until the end of the Project at Critical Decision 4. This document is applicable only to site activities, which are defined as those that occur within the perimeter of the fenced-off NIF construction zone and the Target Chamber Assembly Area (Helipad). The associated Special Equipment laydown and construction support areas listed in Appendix B are not under this plan; their safety provisions are discussed in the Appendix. Prototype and other support activities, such as the Amplifier Laboratory and Frame Assembly Unit assembly area, are not included in this plan. After completion of the Operational Readiness Review, the Facility Safety Procedure, Operational Safety Requirements, and Operational Safety Procedures are the governing safety documents for the operating facility. The S/O and SE project elements are required to implement measures that create a universal awareness of and promote safe job practices at the site. This includes all Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory, Sandia National Laboratories, University of Rochester, supplement labor organization, and subcontractor employees; visitors; and guests serving the S/O and SE effort.

  12. Principles of construction of ultrasonic tomographs for solution of problems of nondestructive testing in mechanical engineering

    Science.gov (United States)

    Bolotina, I.; Bulavinov, A.; Pinchuk, R.; Salchak, Y.

    2016-04-01

    The paper considers the problems of ultrasonic nondestructive testing of products intended for mechanical engineering. The functional and electronic circuits of an ultrasonic tomograph are presented. The function of signal radiation from the clocked multielement apparatus is described, the cross-functional flowchart of the prototype of a US tomograph is considered. The development trends of ultrasonic tomography for near-term outlook are demonstrated.

  13. On the Schedule Control of Large Metallurgical Construction Engineering Projects%大型冶金建设工程项目进度控制研究

    Institute of Scientific and Technical Information of China (English)

    孙忠林

    2015-01-01

    It has important practical significance for improving the metallurgical construction quality level and controlling construction investment to research the schedule control of large metallurgical construction engineering projects.%研究大型冶金建设工程项目进度控制对提高冶金建设质量水平、控制建设投资具有重要的现实意义。

  14. Engraftment of Prevascularized, Tissue Engineered Constructs in a Novel Rabbit Segmental Bone Defect Model

    Directory of Open Access Journals (Sweden)

    Alexandre Kaempfen

    2015-06-01

    Full Text Available The gold standard treatment of large segmental bone defects is autologous bone transfer, which suffers from low availability and additional morbidity. Tissue engineered bone able to engraft orthotopically and a suitable animal model for pre-clinical testing are direly needed. This study aimed to evaluate engraftment of tissue-engineered bone with different prevascularization strategies in a novel segmental defect model in the rabbit humerus. Decellularized bone matrix (Tutobone seeded with bone marrow mesenchymal stromal cells was used directly orthotopically or combined with a vessel and inserted immediately (1-step or only after six weeks of subcutaneous “incubation” (2-step. After 12 weeks, histological and radiological assessment was performed. Variable callus formation was observed. No bone formation or remodeling of the graft through TRAP positive osteoclasts could be detected. Instead, a variable amount of necrotic tissue formed. Although necrotic area correlated significantly with amount of vessels and the 2-step strategy had significantly more vessels than the 1-step strategy, no significant reduction of necrotic area was found. In conclusion, the animal model developed here represents a highly challenging situation, for which a suitable engineered bone graft with better prevascularization, better resorbability and higher osteogenicity has yet to be developed.

  15. Research on the Construction of Tissue Engineering Scaffolds by Alginate-hyaluronic Acid with Different Characteristics

    Institute of Scientific and Technical Information of China (English)

    LI Qin-hua; LIU Li; LIN Dong-qing

    2014-01-01

    This research uses alginate and hyaluronic acid as the main component to prepare support, then explores the possibilities as a tissue engineering scaffold. Firstly, prepare HA with various average molecular weight and alginate with different viscosity, mix them up at a certain proportion and make it into a AlgCa 2+-HA composite scaffold with a film-forming method. This article discusses the feasibility of this scaffold used in tissue engineering field according to the consequence of moisture content testing, mechanical analysis, and scanning electron microscopy analysis. The structure and properties of AlgCa2+-HA composite scaffold are closely related to some factors such as average molecular weight of hyaluronic acid, hyaluronic acid concentration, alginate viscosity, cross-linking agents and processing technology. The AlgCa 2+-HA composite material, which is at different proportions and adding different cross-linking agent,has some certain characteristics:moisture content ranging from 50%to 95%, tensile strength between 2.69 N/mm2 and 4.299 N/mm2, and elongation at break is about 58%to 160%. The prepared AlgCa2+-HA composite scaffolds can be used as tissue engineering scaffolds resulting from its high moisture content, good mechanical properties and ideal pore structure.

  16. HSE Management in Construction Engineering Projects%论施工项目中的HSE管理

    Institute of Scientific and Technical Information of China (English)

    顾国辉

    2015-01-01

    In the HSE management system,H stands for Health,S stands for Safety and E stands for Environment. At present,project management efforts in China attach more attention on quality during project implementation,project schedule,control of investment and contact,information management and relationship coordination among different par-ties but pay less attention on the management of environment,occupational health and safety for engineering projects. This paper gives an analysis of existing problems in daily safety management and occupational health management for engineer-ing projects and presents corresponding countermeasures.%HSE 管理体制是健康(Health)、安全(Safety)和环境(Environment)管理体系的简称。目前我国的项目管理工作主要停留在对项目实施阶段质量、进度、投资的控制和合同、信息管理及各方关系的协调等方面,对工程项目的环境、职业健康和安全管理重视不足。基于此,分析了工程项目中日常安全管理和职业健康管理存在的问题,并提出了对策建议。

  17. Analysis of the Electromechanical Installation Cooperate with the Civil Engineering Construction%机电安装与土建施工配合分析

    Institute of Scientific and Technical Information of China (English)

    肖庆丰

    2014-01-01

    In the process of management the construction eng-ineering project, people must pay at ention to the management and coordination of electromechanical engineering cooperates with civil engineering construction. In this article, the author combines with the project example of green land square in a city and briefly analyzes and discusses to the coordination ma-nagement of electromechanical instal ation and civil enginee-ring construction.%在管理建筑工程项目的过程中,必须重视机电工程和土建施工配合的管理以及协调。本文结合某市绿地广场工程实例,对建筑工程机电安装与土建施工的协调管理进行了浅要的分析与探讨。

  18. 建筑安装工程造价全过程控制%The Whole Process Control of Engineering Cost of Construction and Installation

    Institute of Scientific and Technical Information of China (English)

    王学广

    2014-01-01

    The construction and instalation engineering occu- pies an important position in the construction project, so its co- st control in engineering is the core work. Therefore, it has im- portant significance to study the cost control in whole process of construction and instalation engineering for controlling the cost of construction project.%建筑安装工程在建设项目工程中占据重要地位,建筑安装工程的全过程造价控制在工程中是比较核心的工作。因此,研究建筑安装工程全过程的造价控制对控制整个建筑工程的造价具有重要意义。

  19. 建筑工程施工进度的控制及管理%Building engineering construction schedule control and management

    Institute of Scientific and Technical Information of China (English)

    牛章红

    2016-01-01

    从施工人员、材料设备、施工环境等方面,分析了影响建筑工程施工进度的主要因素,并根据建筑工程施工进度的控制原理,阐述了实际工程进度的编制措施,从而确保项目的顺利完工。%Starting from aspects of construction staff,material equipment and construction environment,the paper analyzes major factors influen-cing building engineering construction schedule. According to building engineering construction schedule controlling principles,it describes actu-al engineering schedule compiling measures,so as to guarantee the smooth completion of the project.

  20. Explore the Effective Measures of the Construction Engineering Schedule Control%建筑工程进度控制的有效措施探究

    Institute of Scientific and Technical Information of China (English)

    雷霆

    2014-01-01

    施工进度是建筑工程工作的重要方面,本文以建筑工程施工进度的影响因素为切入点,对建筑工程进度控制的有效措施进行了探索和研究,以期为我国建筑事业的发展提供一些参考和借鉴。%The construction progress is an important part of construction engineering work. In this article, the author takes the influence factors of construction engineering schedule as the breakthrough point to explore and study the effective mea-sures of the construction engineering schedule control so as to provide some references for the development of Chinese bu-ilding industry.

  1. Control and Calibration of a Staubli RX130 Robotic Arm for Construction of Surface Current Coils

    Science.gov (United States)

    Vanmeter, Patrick; Crawford, Christopher; Guler, Emre; Fugal, Mario; Irvin, Bradley

    2013-10-01

    Precision low energy neutron experiments require extremely uniform magnetic fields for manipulating the neutron spin. Such fields can be generated with surface current coils-precision 3-dimensional printed circuits. We are developing a facility to etch out these circuits on copper-plated curved forms using a high-speed spindle attached to the end-effector of a Staubli RX130 six-axis robotic arm. We describe our mathematical model of the robotic links and the software system we designed to control the motion of the arm and to prevent collisions during actuations. We developed a calibration procedure to achieve accuracy of 30 microns in the position of drill.

  2. Engineered myocardial tissues constructed in vivo using cardiomyocyte-like cells derived from bone marrow mesenchymal stem cells in rats

    Directory of Open Access Journals (Sweden)

    Xing Yujie

    2012-01-01

    Full Text Available Abstract Background To explore the feasibility of constructing engineered myocardial tissues (EMTs in vivo, using polylactic acid -co-glycolic acid (PLGA for scaffold and cardiomyocyte-like cells derived from bone marrow mesenchymal stem cells (BMMSCs for seeded cells. Methods BMMSCs were isolated from femur and tibia of Sprague-Dawley (SD rats by density-gradient centrifugation. The third passage cells were treated with 10 μmol/L 5-azacytidine (5-aza and 0.1 μmol/L angiotensin II (Ang II for 24 h, followed by culturing in complete medium for 3 weeks to differentiated into cardiomyocyte-like cells. The cardiomyocyte-like cells were seeded into PLGA scaffolds to form the grafts. The grafts were cultured in the incubator for three days and then implanted into the peritoneal cavity of SD rats. Four weeks later, routine hematoxylin-eosin (HE staining, immunohistochemical staining for myocardium-specific cardiac troponin I (cTnI, scanning electron microscopy and transmission electron microscopy were used to analyze the morphology and microconstruction of the EMTs in host rats. Results HE staining showed that the cardiomyocyte-like cells distributed equally in the PLGA scaffold, and the nuclei arranged in the spindle shape. Immunohistochemical staining revealed that majority of engrafted cells in the PLGA -Cardiomyocyte-like cells group were positive for cTnI. Scanning electron microscopy showed that the inoculated cells well attached to PLGA and grew in 3 dimensions in construct. Transmission electron microscopy showed that the EMTs contained well arranged myofilaments paralleled to the longitudinal cell axis, the cells were rich in endoplasmic reticulum and mitochondria, while desmosomes, gap junction and Z line-like substances were also can be observed as well within the engrafted cells. Conclusion We have developed an in vivo method to construct engineered myocardial tissue. The in vivo microenvironment helped engrafted cells/tissue survive and

  3. Tissue Engineering and Regenerative Medicine in Iran: Current State of Research and Future Outlook.

    Science.gov (United States)

    Mobini, Sahba; Khanmohammadi, Manijeh; Heidari-Vala, Hamed; Samadikuchaksaraei, Ali; Moshiri, Ali; Kazemnejad, Somaieh

    2015-07-01

    During two decades ago, Iran has exhibited remarkable increase in scientific publication in different aspects including tissue engineering and regenerative medicine (TERM). The field of TERM in Iran dates comes back to the early part of the 1990 and the advent of stem cell researches. Nowadays, Iran is one of the privileged countries in stem cell therapy in the Middle East. The next major milestone in TERM was application and fabrication of scaffolds for tissue engineering in the early 2000s with a focus on engineering bone and cartilage tissue. A good amount of thoughtful works has also yielded prototypes of other tissue substitutes such as nerve conduits, liver, and even heart. However, forward movement to clinical application of these products is still far from offering clinically acceptable solutions. In this study, we have presented a comprehensive review on the efforts of Iranian scientists in different issues of tissue engineering and regenerative medicine field.

  4. Evolution of Inter-domain Traffic Engineering:Standards, Research and Current Applications

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper briefly describes how inter-domain traffic engineering (TE) is evolving and how it can be used for effective commercial networking as well as for high performance networking in Asia and around the globe.

  5. POSSIBILITIES OF THE USE OF GRP PIPING IN THE CONSTRUCTION AND RECONSTRUCTION OF ENGINEERING NETWORKS

    OpenAIRE

    ikitina Irina Nikolaevna; Eremeev Aleksandr Vladimirovich

    2015-01-01

    Today in modern construction new technologies and materials are used for the manufacture of pipelines for water supply and sanitation. They are supposed to operate for at least 50 years. Unlike plastic pipes, fiberglass ones may be made of larger sizes — up to 3700 mm in diameter. They are produced using the technology of optical fiber winding, which is carried out according to modern international standards of quality. The basic raw materials — fiberglass and resin — are produced in Russia, ...

  6. The Effects of Extracellular Matrix on Tissue Engineering Construction of Cartilage in Vitro

    Institute of Scientific and Technical Information of China (English)

    YU Li; LI Fa-tao; TANG Ming-qiao; YAN Wei-qun

    2006-01-01

    The effects of various cartilage extracellular matrix on the construction of rabbit growth plate cartilage tissue in vitro were studied. The results show that collagen, proteoglycan and hyaluronic acid can promote the growth of cultured chondrocytes but the effects of various cartilage extracellular matrix(ECM)on chondrocyte differentiation are different. Collagen can promote the hypertrophy of chondrocytes while proteoglycan and hyaluronic acid inhibit the transition of mature chondrocytes into hypertrophied chondrocytes.

  7. Matrix production and organization by endothelial colony forming cells in mechanically strained engineered tissue constructs.

    Directory of Open Access Journals (Sweden)

    Nicky de Jonge

    Full Text Available AIMS: Tissue engineering is an innovative method to restore cardiovascular tissue function by implanting either an in vitro cultured tissue or a degradable, mechanically functional scaffold that gradually transforms into a living neo-tissue by recruiting tissue forming cells at the site of implantation. Circulating endothelial colony forming cells (ECFCs are capable of differentiating into endothelial cells as well as a mesenchymal ECM-producing phenotype, undergoing Endothelial-to-Mesenchymal-transition (EndoMT. We investigated the potential of ECFCs to produce and organize ECM under the influence of static and cyclic mechanical strain, as well as stimulation with transforming growth factor β1 (TGFβ1. METHODS AND RESULTS: A fibrin-based 3D tissue model was used to simulate neo-tissue formation. Extracellular matrix organization was monitored using confocal laser-scanning microscopy. ECFCs produced collagen and also elastin, but did not form an organized matrix, except when cultured with TGFβ1 under static strain. Here, collagen was aligned more parallel to the strain direction, similar to Human Vena Saphena Cell-seeded controls. Priming ECFC with TGFβ1 before exposing them to strain led to more homogenous matrix production. CONCLUSIONS: Biochemical and mechanical cues can induce extracellular matrix formation by ECFCs in tissue models that mimic early tissue formation. Our findings suggest that priming with bioactives may be required to optimize neo-tissue development with ECFCs and has important consequences for the timing of stimuli applied to scaffold designs for both in vitro and in situ cardiovascular tissue engineering. The results obtained with ECFCs differ from those obtained with other cell sources, such as vena saphena-derived myofibroblasts, underlining the need for experimental models like ours to test novel cell sources for cardiovascular tissue engineering.

  8. Construction and Expression of β-galactosidase Genetically Engineered Lactococcus lactis

    Institute of Scientific and Technical Information of China (English)

    吕晓英; 张朝武; 裴晓方; 刘祥; 余倩; 刘衡川

    2004-01-01

    Our objective is to solve the lactose malabsorption and intolerance of human beings by combining mlcro-ecology path with genetic engineering technique. Plasmid pMG36e was used to clone and express a β-galactosidase gene from L.delbrueckii bulgaricus strain 1. 1480 in the Lactococcus lactis subsp, cremoris MG1363 and Lactococcus lactis subsp. lactis IL1403. The recombinant plasmid was preserved and proliferated in Escherichia coli ( E. coli) JM109, and transformed into MG1363 and 1L1403 by electroporation. The protein expression was studied. (1) The bifidobacterium culture medium (BBL) was suitable for the growth of the strain 1. 1480. (2) With 13 amino acids at the N-terminus from the vector, β-galactosidase fusion protein (which retained the enzyme activity) could be successfully expressed in E. coli JM109, MG1363 and IL1403, but the expression quantity was larger in the former than in the latter two. (3) The SD sequence designed could be successfully recognized by both the E. coli and the Lactococcus lactis, but the expression level of the non-fusion β-galac-tosidase protein was lower than that of the fusion protein in the same host. The β-galactosidase genetically engineered E.coli JM109 is a useful tool to produce this enzyme in vitro. The signal peptide of the usp45 protein from the Lactococcus lactis can be added before the promoter sequence to promote β-galactosidase secretion from Lactococcus lactis. The potential application of the β-galactosidase genetically engineered MG1363 and IL1403 to cure the lactose malabsorption and lactose intolerance in both health food and medicine is promising。

  9. Construction of lycopene-overproducing Saccharomyces cerevisiae by combining directed evolution and metabolic engineering.

    Science.gov (United States)

    Xie, Wenping; Lv, Xiaomei; Ye, Lidan; Zhou, Pingping; Yu, Hongwei

    2015-07-01

    Improved supply of farnesyl diphosphate (FPP) is often considered as a typical strategy for engineering Saccharomyces cerevisiae towards efficient terpenoid production. However, in the engineered strains with enhanced precursor supply, the production of the target metabolite is often impeded by insufficient capacity of the heterologous terpenoid pathways, which limits further conversion of FPP. Here, we tried to assemble an unimpeded biosynthesis pathway by combining directed evolution and metabolic engineering in S. cerevisiae for lycopene-overproduction. First, the catalytic ability of phytoene syntheses from different sources was investigated based on lycopene accumulation. Particularly, the lycopene cyclase function of the bifunctional enzyme CrtYB from Xanthophyllomyces dendrorhous was inactivated by deletion of functional domain and directed evolution to obtain mutants with solely phytoene synthase function. Coexpression of the resulting CrtYB11M mutant along with the CrtE and CrtI genes from X. dendrorhous, and the tHMG1 gene from S. cerevisiae led to production of 4.47 mg/g DCW (Dry cell weight) of lycopene and 25.66 mg/g DCW of the by-product squalene. To further increase the FPP competitiveness of the lycopene synthesis pathway, we tried to enhance the catalytic performance of CrtE by directed evolution and created a series of pathway variants by varying the copy number of Crt genes. Finally, fed-batch fermentation was conducted for the diploid strain YXWPD-14 resulting in accumulation of 1.61 g/L (24.41 mg/g DCW) of lycopene, meanwhile, the by-production of squalene was reduced to below 1 mg/g DCW.

  10. "Ain't no one here but us social forces": constructing the professional responsibility of engineers.

    Science.gov (United States)

    Davis, Michael

    2012-03-01

    There are many ways to avoid responsibility, for example, explaining what happens as the work of the gods, fate, society, or the system. For engineers, "technology" or "the organization" will serve this purpose quite well. We may distinguish at least nine (related) senses of "responsibility", the most important of which are: (a) responsibility-as-causation (the storm is responsible for flooding), (b) responsibility-as-liability (he is the person responsible and will have to pay), (c) responsibility-as-competency (he's a responsible person, that is, he's rational), (d) responsibility-as-office (he's the responsible person, that is, the person in charge), and (e) a responsibility-as-domain-of-tasks (these are her responsibilities, that is, the things she is supposed to do). For all but the causal sense of responsibility, responsibility may be taken (in a relatively straightforward sense)-and generally is. Why then would anyone want to claim that certain technologies make it impossible to attribute responsibility to engineers (or anyone else)? In this paper, I identify seven arguments for that claim and explain why each is fallacious. The most important are: (1) the argument from "many hands", (2) the argument from individual ignorance, and (3) the argument from blind forces. Each of these arguments makes the same fundamental mistake, the assumption that a certain factual situation, being fixed, settles responsibility, that is, that individuals, either individually or by some group decision, cannot take responsibility. I conclude by pointing out the sort of decisions (and consequences) engineers have explicitly taken responsibility for and why taking responsibility for them is rational, all things considered. There is no technological bar to such responsibility. © Springer Science+Business Media B.V. 2010

  11. DEVELOPMENT OF NANOTECHNOLOGIES IN CONSTRUCTION – A TASK WHICH IS OF GREAT IMPORTANCE FOR SCIENTISTS AND ENGINEERS

    Directory of Open Access Journals (Sweden)

    KARPOV Alexey Ivanovich

    2013-02-01

    Full Text Available Publications play a significant role by supporting the creation and application of nanotechnological products through information. Therefore the Russian Engineering Academy decided to establish the Internet-journal «Nanotechnologies in Construction» in 2009. According to the opinion of many specialists and experts, the concept to publish such journal proved to be very beneficial. The specialized information has strongly influenced the work of scientists in the area of construction nanotechnologies. At the authors’ and readers’ request, the editors launched a new section aimed at publishing the main results of Ph.D. and Doctorate theses, to popularize the subject of the nanoindustry in construction and to increase the consumers’ trust in the domestic goods produced by the nanoindustry. The published material is a good theoretical basis for post graduate students and persons working for a doctorate. In this issue we present the main results of the following Ph.D. theses: «Modification of anhydride compositions with ultra- and nanodispersed additives» by I.S. Maeva and «Nanostructured perlite binding and its application to foam concrete» by E.V. Miroshnikova.

  12. The Influence of Engineering-Geological Conditions on the Construction of the Radioactive Waste Dump

    Directory of Open Access Journals (Sweden)

    Jozef Kuzma

    2007-01-01

    Full Text Available A secure stability and reliable serviceability of the radioactive dump is a difficult engineering problem. Due to the difficult geological formations determined mainly by a high compressibility, the low shear strength of soils, and the high ground water level, or a high upward hydrostatic pressure these demands will increase. An influence of the required reliability and the lifespan on the structure of these specific objects is considerable. In this contribution, we are trying to contribute to the problem of solving these difficulties and complicated problems.

  13. Constructing a Mass-Current Radiation-Reaction Force For Numerical Simulations

    CERN Document Server

    Rezzolla, L; Asada, H; Baumgarte, T W; Shapiro, S L

    1999-01-01

    We present a new set of 3.5 Post-Newtonian equations in which Newtonian hydrodynamics is coupled to the nonconservative effects of gravitational radiation emission. Our formalism differs in two significant ways from a similar 3.5 Post-Newtonian approach proposed by Blanchet (1993, 1997). Firstly we concentrate only on the radiation-reaction effects produced by a time-varying mass-current quadrupole $S_{ij}$. Secondly, we adopt a gauge in which the radiation-reaction force densities depend on the fourth time derivative of $S_{ij}$, rather than on the fifth, as in Blanchet's approach. This difference makes our formalism particularly well-suited to numerical implementation and could prove useful in performing fully numerical simulations of the recently discovered $r$-mode instability for rotating neutron stars subject to axial perturbations.

  14. Current and future regenerative medicine - principles, concepts, and therapeutic use of stem cell therapy and tissue engineering in equine medicine

    DEFF Research Database (Denmark)

    Koch, Thomas Gadegaard; Berg, Lise Charlotte; Betts, Dean H.

    2009-01-01

    This paper provides a bird's-eye perspective of the general principles of stem-cell therapy and tissue engineering; it relates comparative knowledge in this area to the current and future status of equine regenerative medicine.The understanding of equine stem cell biology, biofactors, and scaffolds...... mesenchymal stromal cells, unless there is proof that they exhibit the fundamental in vivo characteristics of pluripotency and the ability to self-renew. That said, these cells from various tissues hold great promise for therapeutic use in horses. The 3 components of tissue engineering - cells, biological...... factors, and biomaterials - are increasingly being applied in equine medicine, fuelled by better scaffolds and increased understanding of individual biofactors and cell sources.The effectiveness of stem cell-based therapies and most tissue engineering concepts has not been demonstrated sufficiently...

  15. Construction Schedule Risk Factors Analysis and Judgment of Civil Engineering%土木工程施工进度风险因素分析与判断

    Institute of Scientific and Technical Information of China (English)

    赵春安; 赵剑

    2013-01-01

    随着我国经济的飞速发展,土木工程施工建设占有的位置越来越重要。其中土木工程施工进度风险是土木工程施工的重要影响因素。本文通过对土木工程施工进度风险影响因素的分析,提出一些关于控制土木工程施工进度风险因素的意见。%With the rapid development of our economy, civil engineering construction occupies the more and more impor-tant position. The civil engineering construction schedule risk is an important factor in the civil engineering construction. Th-is paper through the analysis of affecting risk factors on civil engineering construction schedule puts forward some factors to control the risk of civil engineering construction schedule.

  16. Constructal approach to bio-engineering: the ocular anterior chamber temperature

    Science.gov (United States)

    Lucia, Umberto; Grisolia, Giulia; Dolcino, Daniela; Astori, Maria Rosa; Massa, Eugenio; Ponzetto, Antonio

    2016-08-01

    The aim of this work was to analyse the pressure inside the eyes anterior chamber, namedintraocular pressure (IOP), in relation to the biomechanical properties of corneas. The approach used was based on the constructal law, recently introduced in vision analysis. Results were expressed as the relation between the temperature of the ocular anterior chamber and the biomechanical properties of the cornea. The IOP, the elastic properties of the cornea, and the related refractive properties of the eye were demonstrated to be dependent on the temperature of the ocular anterior chamber. These results could lead to new perspectives for experimental analysis of the IOP in relation to the properties of the cornea.

  17. Significance exaggerated of the activity of the construction in Spain; inflection and current decline? The difficult to their sostenibilitiy

    Directory of Open Access Journals (Sweden)

    José María Serrano

    2010-04-01

    Full Text Available For some time the activity of the construction, in its different sections, (housings, works with non residential ends, transport, public works… has had special significance inside the productive system in Spain. During the last decade it has reached an exaggerated weight, so much in their participation in the GDP like of people occupied in her. The some regions that proportion represents exaggerated ends. The current economic crisis has affected with intensity to the group of the sector of the construction, making more intense the consequences of the economic recession. Everything it, is not only as a consequence of a crisis of the situation. Rather she is due to structural reasons. It seems probable that, from now on, the group of the Spanish economic system, it should be articulated with a new organization, a new productive model, where the construction only means a more reduced part of the same one. That is easy to say, but very difficult of getting it. It represents a great challenge face to the future.

  18. Construction and characterization of a tissue-engineered oral mucosa equivalent based on a chitosan-fish scale collagen composite.

    Science.gov (United States)

    Terada, Michiko; Izumi, Kenji; Ohnuki, Hisashi; Saito, Taro; Kato, Hiroko; Yamamoto, Marie; Kawano, Yoshiro; Nozawa-Inoue, Kayoko; Kashiwazaki, Haruhiko; Ikoma, Toshiyuki; Tanaka, Junzo; Maeda, Takeyasu

    2012-10-01

    This study was designed to (1) assess the in vitro biocompatibility of a chitosan-collagen composite scaffold (C3) constructed by blending commercial chitosan and tilapia scale collagen with oral mucosa keratinocytes, (2) histologically and immunohistochemically characterize an ex vivo-produced oral mucosa equivalent constructed using the C3 (EVPOME-C), and (3) compare EVPOME-C with oral mucosa constructs utilizing AlloDerm® (EVPOME-A), BioMend® Extend™ (EVPOME-B), and native oral mucosa. C3 scaffold had a well-developed fibril network and a sufficiently small porosity to prevent keratinocytes from growing inside the scaffold after cell-seeding. The EVPOME oral mucosa constructs were fabricated in a chemically defined culture system. After culture at an air-liquid interface, EVPOME-C and EVPOME-B had multilayered epithelium with keratinization, while EVPOME-A had a more organized stratified epithelium. Ki-67 and p63 immunolabeled cells in the basal layer of all EVPOMEs suggested a regenerative ability. Compared with native oral mucosa, the keratin 15 and 10/13 expression patterns in all EVPOMEs showed a less-organized differentiation pattern. In contrast to the β1-integrin and laminin distribution in EVPOME-A and native oral mucosa, the subcellular deposition in EVPOME-C and EVPOME-B indicated that complete basement membrane formation failed. These findings demonstrated that C3 has a potential application for epithelial tissue engineering and provides a new potential therapeutic device for oral mucosa regenerative medicine.

  19. Investigation of the current requirements engineering practices among software developers at the Universiti Utara Malaysia Information Technology (UUMIT) centre

    Science.gov (United States)

    Hussain, Azham; Mkpojiogu, Emmanuel O. C.; Abdullah, Inam

    2016-08-01

    Requirements Engineering (RE) is a systemic and integrated process of eliciting, elaborating, negotiating, validating and managing of the requirements of a system in a software development project. UUM has been supported by various systems developed and maintained by the UUM Information Technology (UUMIT) Centre. The aim of this study was to assess the current requirements engineering practices at UUMIT. The main problem that prompted this research is the lack of studies that support software development activities at the UUMIT. The study is geared at helping UUMIT produce quality but time and cost saving software products by implementing cutting edge and state of the art requirements engineering practices. Also, the study contributes to UUM by identifying the activities needed for software development so that the management will be able to allocate budget to provide adequate and precise training for the software developers. Three variables were investigated: Requirement Description, Requirements Development (comprising: Requirements Elicitation, Requirements Analysis and Negotiation, Requirements Validation), and Requirement Management. The results from the study showed that the current practice of requirement engineering in UUMIT is encouraging, but still need further development and improvement because a few RE practices were seldom practiced.

  20. [Construction of hpaA gene-engineered attenuated Salmonella typhimurium vaccine strain].

    Science.gov (United States)

    Zhu, Senlin; Chen, Minhu; Chen, Jie; Hu, Pinjin; Li, Guoqing

    2002-02-01

    To express Helicobacter pylori hpaA gene in attenuated Salmonella typhimurium vaccine vehicle, and elucidate the potential value of attenuated Salmonella typhimurium as a vector expressing Helicobacter pylori antigens, by means of molecular biology, 783 bp hpaA gene was cloned into NcoI-SalI site of a procaryotic expression plasmid pTrc99A, and the recombinant plasmid was then used to transform an attenuated Salmonella typhimurium vaccine strain SL3261, and the positive clones were screened by PCR and restriction enzyme digestion. HpaA expression was analyzed by SDS-PAGE and Western blot. Two and 10 days after recombinant strain intragastric immunization, the C57BL/6 mice was sacrificed, and the spleen and terminal ileum was cultured for recombinant strain. The results showed that a recombinant procaryotic expression plasmid pTrc99A-hpaA was constructed, and the recombinant plasmid was then introduced into an attenuated Salmonella typhimurium vaccine strain SL3261 successfully. HpaA was expressed in the recombinant strains as a 30 kD protein, and also its immunogenicity was confirmed by Western blot. Recombinant strain was found in both spleen and terminal ileum of each mouse two and ten days after intragastric immunization. We concluded that a recombinant live attenuated Salmonella typhimurium vaccine strain expressing Helicobacter pylori hpaA gene was constructed and identified, and this work will help to develop oral recombinant live vaccine strains against Helicobacter pylori infection.

  1. Mechanical and biochemical mapping of human auricular cartilage for reliable assessment of tissue-engineered constructs.

    Science.gov (United States)

    Nimeskern, Luc; Pleumeekers, Mieke M; Pawson, Duncan J; Koevoet, Wendy L M; Lehtoviita, Iina; Soyka, Michael B; Röösli, Christof; Holzmann, David; van Osch, Gerjo J V M; Müller, Ralph; Stok, Kathryn S

    2015-07-16

    It is key for successful auricular (AUR) cartilage tissue-engineering (TE) to ensure that the engineered cartilage mimics the mechanics of the native tissue. This study provides a spatial map of the mechanical and biochemical properties of human auricular cartilage, thus establishing a benchmark for the evaluation of functional competency in AUR cartilage TE. Stress-relaxation indentation (instantaneous modulus, Ein; maximum stress, σmax; equilibrium modulus, Eeq; relaxation half-life time, t1/2; thickness, h) and biochemical parameters (content of DNA; sulfated-glycosaminoglycan, sGAG; hydroxyproline, HYP; elastin, ELN) of fresh human AUR cartilage were evaluated. Samples were categorized into age groups and according to their harvesting region in the human auricle (for AUR cartilage only). AUR cartilage displayed significantly lower Ein, σmax, Eeq, sGAG content; and significantly higher t1/2, and DNA content than NAS cartilage. Large amounts of ELN were measured in AUR cartilage (>15% ELN content per sample wet mass). No effect of gender was observed for either auricular or nasoseptal samples. For auricular samples, significant differences between age groups for h, sGAG and HYP, and significant regional variations for Ein, σmax, Eeq, t1/2, h, DNA and sGAG were measured. However, only low correlations between mechanical and biochemical parameters were seen (Rbiochemical map of human auricular cartilage. Regional variations in mechanical and biochemical properties were demonstrated in the auricle. This finding highlights the importance of focusing future research on efforts to produce cartilage grafts with spatially tunable mechanics. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Current and future delivery systems for engineered nucleases: ZFN, TALEN and RGEN.

    Science.gov (United States)

    Ul Ain, Qurrat; Chung, Jee Young; Kim, Yong-Hee

    2015-05-10

    Gene therapy by engineered nucleases is a genetic intervention being investigated for curing the hereditary disorders by targeting selected genes with specific nucleotides for establishment, suppression, abolishment of a function or correction of mutation. Here, we review the fast developing technology of targeted genome engineering using site specific programmable nucleases zinc finger nucleases (ZFNs), transcription activator like nucleases (TALENs) and cluster regulatory interspaced short palindromic repeat/CRISPR associated proteins (CRISPR/Cas) based RNA-guided DNA endonucleases (RGENs) and their different characteristics including pros and cons of genome modifications by these nucleases. We have further discussed different types of delivery methods to induce gene editing, novel development in genetic engineering other than nucleases and future prospects.

  3. The Small Helm Project: an academic activity addressing international corruption for undergraduate civil engineering and construction management students.

    Science.gov (United States)

    Benzley, Steven E

    2006-04-01

    This paper presents an academic project that addresses the issue of international corruption in the engineering and construction industry, in a manner that effectively incorporates several learning experiences. The major objectives of the project are to provide the students a learning activity that will 1) make a meaningful contribution within the disciplines being studied; 2) teach by experience a significant principle that can be valuable in numerous situations during an individual's career, and 3) engage the minds, experiences, and enthusiasm of the participants in a real ethical challenge that is prevalent in all of their chosen professional fields. The paper describes the full details of the project, the actual implementation of it during Winter Semester 2005, the experiences gained during the initial trial, and the modifications and improvements incorporated for future implementation.

  4. Construction and evaluation of an exopolysaccharide-producing engineered bacterial strain by protoplast fusion for microbial enhanced oil recovery.

    Science.gov (United States)

    Sun, Shanshan; Luo, Yijing; Cao, Siyuan; Li, Wenhong; Zhang, Zhongzhi; Jiang, Lingxi; Dong, Hanping; Yu, Li; Wu, Wei-Min

    2013-09-01

    Enterobacter cloacae strain JD, which produces water-insoluble biopolymers at optimal temperature of 30°C, and a thermophilic Geobacillus strain were used to construct an engineered strain for exopolysaccharide production at high temperatures by protoplast fusion. The obtained fusant strain ZR3 produced exopolysaccharides at up to 45°C with optimal growth temperature at 35°C. The fusant produced exopolysaccharides of approximately 7.5 g/L or more at pH between 7.0 and 9.0. The feasibility of the enhancement of crude oil recovery with the fusant was tested in a sand-packed column at 40°C. The results demonstrated that bioaugmentation of the fusant was promising approach for MEOR. Mass growth of the fusant was confirmed in fermentor tests. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. 3D Printing of Tissue Engineered Constructs for In Vitro Modeling of Disease Progression and Drug Screening.

    Science.gov (United States)

    Vanderburgh, Joseph; Sterling, Julie A; Guelcher, Scott A

    2017-01-01

    2D cell culture and preclinical animal models have traditionally been implemented for investigating the underlying cellular mechanisms of human disease progression. However, the increasing significance of 3D vs. 2D cell culture has initiated a new era in cell culture research in which 3D in vitro models are emerging as a bridge between traditional 2D cell culture and in vivo animal models. Additive manufacturing (AM, also known as 3D printing), defined as the layer-by-layer fabrication of parts directed by digital information from a 3D computer-aided design file, offers the advantages of simultaneous rapid prototyping and biofunctionalization as well as the precise placement of cells and extracellular matrix with high resolution. In this review, we highlight recent advances in 3D printing of tissue engineered constructs that recapitulate the physical and cellular properties of the tissue microenvironment for investigating mechanisms of disease progression and for screening drugs.

  6. EGATEC: A new high-resolution engineering model of the global atmospheric electric circuit—Currents in the lower atmosphere

    Science.gov (United States)

    Odzimek, A.; Lester, M.; Kubicki, M.

    2010-09-01

    We present a new high-resolution model of the Earth's global atmospheric electric circuit (GEC) represented by an equivalent electrical network. Contributions of clouds to the total resistance of the atmosphere and as current generators are treated more realistically than in previous GEC models. The model of cloud current generators is constructed on the basis of the ISCCP cloud data and the OTD/LIS lightning flash rates and TRMM rainfall data. The current generated and the electric resistance can be estimated with a spatial resolution of several degrees in latitude and longitude and 3 hour time resolution. The resistance of the atmosphere is calculated using an atmospheric conductivity model which is spatially dependent and sensitive to the level of solar activity. An equivalent circuit is constructed assuming the ionosphere and ground are ideal conductors. The circuit solution provides diurnal variations of the ionospheric potential and the GEC global current at the 3 hour time resolution as well as the global distributions and diurnal variations of the air-Earth current density and electric field. The model confirms that the global atmospheric electric activity peaks daily at ˜21 UT. The diurnal variation of the ionospheric potential and the global current have a maximum at 12 and 21-24 UT in July and at 9 and 21 UT in December, and a global minimum at 3-6 UT independent of season. About 80% of the current is generated by thunderstorm convective clouds and 20% by mid-level rain clouds.

  7. Topical issues of simulation construction development in Modern Electric Power Engineering

    Science.gov (United States)

    Magid, S. I.; Arkhipova, E. N.; Zagretdinov, I. Sh.

    2015-12-01

    Issues of the history of development of foreign and domestic simulation technology and its current state and effectiveness are discussed. A necessity for the normative evaluation of simulator effectiveness and quality has been identified. A determination has been given for the notion of didactic effectiveness.

  8. Environmental tasks of engineering geology in the construction of nuclear power installations

    Energy Technology Data Exchange (ETDEWEB)

    Hrasna, M. (Komenskeho Univ., Bratislava (Czechoslovakia). Prirodovedecka Fakulta)

    1984-01-01

    A nuclear power installation shoUld be sited in an area without large and intensive geodynamic phenomena such as seismicity, gravitation movement, subsidence, etc., an area with mineral and drinking water resources, deposits of mineral raw materials, quality farmland and protected areas. With regard to demands on the quality of foundation soil and the ground water level it will always be necessary to secure the safe foundation of buildings with possible radioactivity escape. Most such buildings are founded on a solid foundation slab. The definitive siting of the nuclear power facility should be decided upon during the project design preparation stage when most geological surveying is done. During the pre-project stage a quantitative determination is made of all characteristics of rocks on the site. Monitoring and surveillance is conducted during construction.

  9. POSSIBILITIES OF THE USE OF GRP PIPING IN THE CONSTRUCTION AND RECONSTRUCTION OF ENGINEERING NETWORKS

    Directory of Open Access Journals (Sweden)

    ikitina Irina Nikolaevna

    2015-12-01

    Full Text Available Today in modern construction new technologies and materials are used for the manufacture of pipelines for water supply and sanitation. They are supposed to operate for at least 50 years. Unlike plastic pipes, fiberglass ones may be made of larger sizes — up to 3700 mm in diameter. They are produced using the technology of optical fiber winding, which is carried out according to modern international standards of quality. The basic raw materials — fiberglass and resin — are produced in Russia, but their production is limited, so they are purchased abroad, which increases the cost of manufacture of this type of piping. However, due to the necessity of laying pipelines of large diameter, which cannot be made with plastic pipes, the manufacture of GRP pipes will increase. The experience of laying and constructing this type of pipelines, for example, in the areas of hot water supply allows concluding that they are able to withstand the temperatures of up to 150 °C, while their weight is four times less than the weight of steel pipes (they are easily installed with the help of small lifting equipment and by a team of six people. It should be noted that the use of fiberglass pipes helps to reduce the costs of system operation, because this type of piping is not subject to corrosion and encrustation of the inner surface, since it has a low level of roughness, which, for example, is 0.013 for a steel pipe, and 0.01 for fiberglass pipe. Thus, it is not necessary to put protective corrosion-resistant coatings and to provide an expensive protection against electrochemical corrosion. Piping made of fiberglass pipes can be designed as underground, above-ground with stacking or raised on poles. It is possible to combine these options.

  10. On the reasons of engineering cost control of construction and control measures%建筑工程造价失控的原因与控制措施

    Institute of Scientific and Technical Information of China (English)

    杨建红; 唐文娟

    2014-01-01

    建筑工程造价方面出现失控情况,不仅制约着行业发展,而且扰乱了经济发展现状,建筑行业未来发展也会有所制约。必须重视建筑工程中对于造价失控现状分析,能够采用控制措施加以调控,加强建筑行业造价方面控制,以带动建筑工程行业发展。%Industry characteristics of the construction industry, the construction cost out of control, not only restricts the development of the industry,but also disturbs the economic development will be restricted,the future development of the construction industry.So,must pay attention to the architectural engineering for analysis of the current situation of the cost control,to control the use of measures to control,strengthen the construction industry cost control,in order to promote the development of construction industry. Scientific regulation of construction project cost is the key to the development of construction industry.

  11. Metabolic engineering of Saccharomyces cerevisiae for production of carboxylic acids: current status and challenges.

    Science.gov (United States)

    Abbott, Derek A; Zelle, Rintze M; Pronk, Jack T; van Maris, Antonius J A

    2009-12-01

    To meet the demands of future generations for chemicals and energy and to reduce the environmental footprint of the chemical industry, alternatives for petrochemistry are required. Microbial conversion of renewable feedstocks has a huge potential for cleaner, sustainable industrial production of fuels and chemicals. Microbial production of organic acids is a promising approach for production of chemical building blocks that can replace their petrochemically derived equivalents. Although Saccharomyces cerevisiae does not naturally produce organic acids in large quantities, its robustness, pH tolerance, simple nutrient requirements and long history as an industrial workhorse make it an excellent candidate biocatalyst for such processes. Genetic engineering, along with evolution and selection, has been successfully used to divert carbon from ethanol, the natural endproduct of S. cerevisiae, to pyruvate. Further engineering, which included expression of heterologous enzymes and transporters, yielded strains capable of producing lactate and malate from pyruvate. Besides these metabolic engineering strategies, this review discusses the impact of transport and energetics as well as the tolerance towards these organic acids. In addition to recent progress in engineering S. cerevisiae for organic acid production, the key limitations and challenges are discussed in the context of sustainable industrial production of organic acids from renewable feedstocks.

  12. The Effects of Scaffold Remnants in Decellularized Tissue Engineered Cardiovascular Constructs on the Recruitment of Blood Cells.

    Science.gov (United States)

    Sanders, Bart; Driessen-Mol, Anita; Bouten, Carlijn; Baaijens, Frank

    2017-03-17

    Decellularized tissue engineered heart valves (DTEHVs) showed remarkable results in translational animal models, leading to recellularization within hours after implantation. This is crucial to enable tissue remodeling. To investigate if the presence of scaffold remnants prior to implantation is responsible for the fast recellularization of DTEHVs, an in vitro mesofluidic system was used. Human granulocyte and agranulocyte fractions were isolated, stained, brought back in suspension, and implemented in the system. Three different types of biomaterials were exposed to the circulating blood cells, consisting of decellularized tissue engineered constructs (DTEC) with or without scaffold remnants, or only bare scaffold. After 5 hours of testing, the granulocyte fraction was depleted faster from the circulation than the agranulocyte fraction. However, only the granulocytes infiltrated into the DTEC with scaffold, migrating towards the scaffold remnants. The agranulocyte population, on the other hand, was only observed on the outer surface. Active cell infiltration was associated with increased levels of MMP-1 secretion in the DTEC including scaffold remnants. Pro-inflammatory cytokines such as IL-1α, IL-6 and TNF-α were significantly upregulated in the DTEC without scaffold remnants. These results indicate that scaffold remnants can influence the immune response in DTEC, being responsible for rapid cell infiltration.

  13. Inter-organizational collaboration in the field of construction: the perspective of an engineering consultancy

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh

    2006-01-01

    In this work in progress we consider the challenges of inter-organizational collaboration in building projects to support higher quality and lower prices. The framework of Carlile (2004) is used to identify and categorize the current situation and needs of different knowledge processes: transfer,......-wide and more local steps to initiate it. Not at least due to fact that the internal management of knowledge in the organizations involved is confronted....

  14. Evaluation of the Growth Environment of a Hydrostatic Force Bioreactor for Preconditioning of Tissue-Engineered Constructs

    Science.gov (United States)

    Reinwald, Yvonne; Leonard, Katherine H.L.; Henstock, James R.; Whiteley, Jonathan P.; Osborne, James M.; Waters, Sarah L.; Levesque, Philippe

    2015-01-01

    Bioreactors have been widely acknowledged as valuable tools to provide a growth environment for engineering tissues and to investigate the effect of physical forces on cells and cell-scaffold constructs. However, evaluation of the bioreactor environment during culture is critical to defining outcomes. In this study, the performance of a hydrostatic force bioreactor was examined by experimental measurements of changes in dissolved oxygen (O2), carbon dioxide (CO2), and pH after mechanical stimulation and the determination of physical forces (pressure and stress) in the bioreactor through mathematical modeling and numerical simulation. To determine the effect of hydrostatic pressure on bone formation, chick femur skeletal cell-seeded hydrogels were subjected to cyclic hydrostatic pressure at 0–270 kPa and 1 Hz for 1 h daily (5 days per week) over a period of 14 days. At the start of mechanical stimulation, dissolved O2 and CO2 in the medium increased and the pH of the medium decreased, but remained within human physiological ranges. Changes in physiological parameters (O2, CO2, and pH) were reversible when medium samples were placed in a standard cell culture incubator. In addition, computational modeling showed that the distribution and magnitude of physical forces depends on the shape and position of the cell-hydrogel constructs in the tissue culture format. Finally, hydrostatic pressure was seen to enhance mineralization of chick femur skeletal cell-seeded hydrogels. PMID:24967717

  15. Development of a process maturity model for engineering, construction and maintenance projects in the oil and gas industry

    Energy Technology Data Exchange (ETDEWEB)

    Veldman, J.; Klingenberg, W. [Faculty of Management and Organization, University of Groningen, PO BOX 800, 9700 AV Groningen (Netherlands)

    2006-07-01

    Process improvement is a topic gaining considerable attention in literature. For the processes of Engineering, Procurement, Construction and Maintenance (i.e. EPCM) projects in the oil and gas industry, no frameworks exist that can guide these firms in the management of these processes. Using a detailed gap analysis we map the typical processes of EPCM-organisations onto the Capability Maturity Model Integrated (CMMI), a stepwise process improvement model that is widely used in the software industry. Our main contribution is the conclusion that CMMI can benefit the management of EPCM-processes to a large degree, since it gives direction to the improvement of a considerable set of processes within EPCM-projects. Additional insight is given into the scientifically neglected area of learning between projects and the relationship between an organisation's goals and targeted areas of process improvement. These issues are absent in CMMI so further research is needed to develop framework support for, amongst others, downstream processes (construction and maintenance), learning between projects and goal driven process improvement.

  16. An Investigation into The Application of Project Management Method in Construction Engineering%建筑工程中项目管理法的应用探析

    Institute of Scientific and Technical Information of China (English)

    邱文军

    2015-01-01

    With the rapid development of China's economy,the construction industry has made great progress,and gradually develops toward the modern enterprise.However,there are still a lot of construction engineering enterprises which have not established management concepts for construction engineering,which hinders the achievement of benefits and development goals.To apply project management method which is an important branch of management,to the management of construction engineering can effectively promote the improvement of construction management efficiency and economic benefits,the smooth realization of the strategic development objectives.This paper analyzed the application project management method in construction engineering,it was believed that it is of great practical significance to the effective management of construction engineering.%随着我国经济的迅速发展,建筑行业取得了飞速发展,并逐渐向现代化企业发展模式转变。然而,有很多建筑型企业尚未树立建筑工程管理理念,这阻碍了效益和发展目标的实现。项目管理法作为管理学的一个重要分支,应用于建筑工程管理时可以有效促进建筑工程管理效率的提高和经济效益的增长,实现战略发展目标的顺利完成。在建筑工程中探析项目管理法的应用,对于建筑工程的有效管理有着重要的现实意义。

  17. Construction of a genetically engineered chimeric apoprotein consisting of sequences derived from lidamycin and neocarzinostatin.

    Science.gov (United States)

    Jiang, Wenguo; Shang, Boyang; Li, Liang; Zhang, Shenghua; Zhen, Yongsu

    2016-01-01

    Neocarzinostatin (NCS) consists of an enediyne chromophore and an apoprotein (NCP). Lidamycin (LDM) is composed of another active enediyne chromophore (AE) and an acidic protein (LDP). Although the structures of NCP and LDP are very similar, LDM has been shown to have an increased tumor-suppressive activity than that of NCS. The aim of this study was to construct a chimeric protein (CMP) that consists of both the terminus residue of NCP and an LDP pocket-forming residue that can bind AE. This CMP will have a structure similar to NCS and an antitumor activity similar to LDM. The assembling efficiency of LDP, CMP, and NCP was 73.9, 1.5, and 1.1%, respectively. The cytotoxicity was consistent with their assembling efficiency of AE in proteins. When CMP-AE and NCP-AE were administered at equivalent AE doses of LDM, the inhibition rate of CMP-AE was the same as LDM and significantly higher than that of NCP-AE. Our study implied that the binding activity between LDP and AE was very specific. The terminus residue of LDP could affect the specifically binding activity. The pocket-forming residue could confer a protective function to the chromophore. Further investigation of its bioactivity might serve as a new drug design strategy and drug-delivery carrier in targeted cancer therapy.

  18. The main goal of engineering geology for designing and construction complex structures in urban areas

    Directory of Open Access Journals (Sweden)

    Drago Ocepek

    2007-12-01

    Full Text Available Work for designing complex structures in urban areas consists of geological-geotechnical investigations and analysis of the quality of rocks, soft rocks and hard soils in the construction area. Urban areas limited the space for designing cutting slopes in stable inclination without reinforcement. In this paper will be presented designing and excavation works with different reinforcement of two different areas in Slovenia built of heterogeneous mixed hard to soft rock masses (Triassic dolomite, limestone and Eocene flysch sediments.Before the start of excavations work and after establishing the retaining measures, the analysis results are checked by monitoring. This monitoring will continue in the phase of exploitation of the objects. Since the cost of these additional investigations and precise analysis with monitoring (SIST - EN 7 - 2004 and measurements is negligible – in comparison with the costs of the permanent reinforcement – if variable conditions are not to intensive, we were able to reduce effectively the investment value of the object.

  19. [Construction and evaluation of an engineered bacterial strain for producing lipopeptide under anoxic conditions].

    Science.gov (United States)

    Liang, Xiao-long; Zhao, Feng; Shi, Rong-jiu; Ban, Yun-he; Zhou, Ji-dong; Han, Si-qin; Zhang, Ying

    2015-08-01

    Biosurfactant-facilitated oil recovery is one of the most important aspects of microbial enhanced oil recovery (MEOR). However, the biosurfactant production by biosurfactant-producing microorganisms, most of which are aerobes, is severely suppressed due to the in-situ anoxic conditions within oil reservoirs. In this research, we successfully engineered a strain JD-3, which could grow rapidly and produce lipopeptide under anoxic conditions, by protoplast confusion using a Bacillus amyloliquefaciens strain BQ-2 which produces biosurfactant aerobically, and a facultative anaerobic Pseudomonas stutzeri strain DQ-1 as parent strains. The alignment of 16S rDNA sequence (99% similarity) and comparisons of cell colony morphology showed that fusant JD-3 was closer to the parental strain B. amyloliquefaciens BQ-2. The surface tension of culture broth of fusant JD-3, after 36-hour cultivation under anaerobic conditions, decreased from initially 63.0 to 32.5 mN · m(-1). The results of thin layer chromatography and infrared spectrum analysis demonstrated that the biosurfactant produced by JD-3 was lipopeptide. The surface-active lipopeptide had a low critical micelle concentration (CMC) of 90 mg · L(-1) and presented a good ability to emulsify various hydrocarbons such as crude oil, liquid paraffin, and kerosene. Strain JD-3 could utilize peptone as nitrogen source and sucrose, glucose, glycerin or other common organics as carbon sources for anaerobic lipopeptide synthesis. The subculture of fusant JD-3 showed a stable lipopeptide-producing ability even after ten serial passages. All these results indicated that fusant JD-3 holds a great potential to microbially enhance oil recovery under anoxic conditions.

  20. Prevention of significant deterioration application for approval to construct SP-100 Ground Engineering System Test Site

    Energy Technology Data Exchange (ETDEWEB)

    1990-04-01

    The following application is being submitted by the US Department of Energy, Richland Operations Office, P.O. Box 550, Richland, Washington 99352, pursuant to WAC 173-403-080, and in compliance with the Department of Ecology Guide to Processing a Prevention of Significant Deterioration (PSD) Permit'' for a new source of airborne radionuclide emissions at the Hanford Site in Washington State. The new source, the SP-100 Ground Engineering System (GES) Test Site, will be located in the 309 Building of the 300 Area. The US Department of Energy (DOE), the National Aeronautics and Space Administration (NASA), and the US Department of Defense (DOD) have entered into an agreement to jointly develop space nuclear reactor power system technology. The DOE has primary responsibility for developing and ground testing the nuclear subsystem. A ground test of a reactor is necessary to demonstrate technology readiness of this major subsystem before proceeding with the flight system development and demonstration. The SP-100 GES Test Site will provide a location for the operation and testing of a prototype space-based, liquid metal-cooled, fast flux nuclear reactor in an environment closely simulating the vacuum and temperature conditions of space operations. The purpose of the GES is to develop safe, compact, light-weight and durable space reactor power system technology. This technology will be used to provide electric power, in the range of tens to hundreds of kilowatts, for a variety of potential future civilian and military space missions requiring long-term, high-power level sources of energy. 20 refs., 8 figs., 7 tabs.

  1. BEST Engineered Hyporheic Zones: Enhanced Hyporheic Exchange and Resazurin and Nitrate Cycling in Constructed Stream Experiments

    Science.gov (United States)

    Herzog, S.; McCray, J. E.; Higgins, C. P.

    2016-12-01

    The hyporheic zone is a hotspot for biogeochemical processing that can attenuate a variety of nonpoint source contaminants in streamwater. However, hyporheic zones in urban and agricultural streams are often degraded and poorly connected with surface water. To increase hyporheic exchange and improve water quality, we introduced engineered streambeds as a stormwater and restoration best management practice. Modifications to streambed hydraulic conductivity and reactivity are termed Biohydrochemical Enhancements for Streamwater Treatment (BEST). BEST are subsurface modules that utilize low-permeability sediments to drive efficient hyporheic exchange, and reactive geomedia to increase reaction rates within the hyporheic zone. This research utilized two artificial stream flumes at the Colorado School of Mines in Golden, CO. Each lined stream flume was 15m long, 0.3m wide, had 0.3m sediment depth, and was continuously dosed with recycled water at 0.25 L/s. One flume served as an all-sand control condition, the other featured BEST modules at 1m spacing with a mixture of 70/30 sand/woodchips (v/v). NaCl breakthrough curves were monitored and analyzed using STAMMT-L, a mobile-immobile exchange model, which showed greater hyporheic exchange and residence times in the BEST stream relative to the control. This result is even more apparent when the calibrated models are used to simulate longer stream reaches. Water quality samples at the reach scale also revealed greater attenuation of nitrate and transformation of the indicator compound resazurin into resorufin. Together these compounds demonstrate that BEST can attenuate contaminants that degrade under anaerobic and aerobic conditions, respectively. These experimental results were also compared to previous numerical simulations to evaluate model accuracy, and show reasonable agreement. Altogether, these results show that BEST may be an effective novel best management practice for improving streamwater quality in urban and

  2. Simultaneous biodegradation of methyl parathion and carbofuran by a genetically engineered microorganism constructed by mini-Tn5 transposon.

    Science.gov (United States)

    Jiang, Jiandong; Zhang, Ruifu; Li, Rong; Gu, Ji-Dong; Li, Shunpeng

    2007-08-01

    A genetically engineered microorganism (GEM) capable of simultaneous degrading methyl parathion (MP) and carbofuran was successfully constructed by random insertion of a methyl parathion hydrolase gene (mpd) into the chromosome of a carbofuran degrading Sphingomonas sp. CDS-1 with the mini-transposon system. The GEM constructed was relatively stable and cell viability and original degrading characteristic was not affected compared with the original recipient CDS-1. The effects of temperature, initial pH value, inoculum size and alternative carbon source on the biodegradation of MP and carbofuran were investigated. GEM cells could degrade MP and carbofuran efficiently in a relatively broad range of temperatures from 20 to 30 degrees C, initial pH values from 6.0 to 9.0, and with all initial inoculation cell densities (10(5)-10(7) CFU ml(-1)), even if alternative glucose existed. The optimal temperature and initial pH value for GEM cells to simultaneously degrade MP and carbofuran was at 30 degrees C and at pH 7.0. The removal of MP and carbofuran by GEM cells in sterile and non-sterile soil were also studied. In both soil samples, 50 mg kg(-1) MP and 25 mg kg(-1) carbofuran could be degraded to an undetectable level within 25 days even if there were indigenous microbial competition and carbon sources effect. In sterile soil, the biodegradation rates of MP and carbofuran were faster, and the decline of the inoculated GEM cells was slower compared with that in non-sterile soil. The GEM constructed in this study was potential useful for pesticides bioremediation in natural environment.

  3. Analysis of software engineering requirement analysis and structure construction%浅析软件工程需求分析与结构建设

    Institute of Scientific and Technical Information of China (English)

    任延璞

    2016-01-01

    软件工程飞速发展,应用于多个不同领域有着各式各样的开发标准,在软件结构建设方面同样存在一定差异。文章通过阐述软件工程需求分析含义,分析软件工程中需求分析的重要性、软件工程需求分析存在的问题,对软件工程需求分析及结构建设展开探讨,旨在为促进软件工程需求分析与结构建设的有序开展提供一些思路。%Software engineering has got a rapid development, which is applied to a variety of different areas, there are some differences in the construction of software structure. By explaining the meaning of software engineering requirement analysis, this paper analyzes the importance of requirement analysis in software engineering, existing problems of software engineering requirement analysis, and discusses the software engineering requirement analysis and structure construction, aiming at providing some ideas for promoting the demand analysis and orderly carried out software engineering structure construction.

  4. Inter-organizational collaboration in the field of construction: the perspective of an engineering consultancy

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh

    2006-01-01

    In this work in progress we consider the challenges of inter-organizational collaboration in building projects to support higher quality and lower prices. The framework of Carlile (2004) is used to identify and categorize the current situation and needs of different knowledge processes: transfer...... in the building industry provides improved quality. However, new needs arise and development of new knowledge processes is required to exchange, understand and negotiate the knowledge needed in closer collaboration. Development of these knowledge processes is complicated and there is a need for both industry...

  5. Innovations in the supply chain and construction engineering of nuclear-based heat transfer components

    Energy Technology Data Exchange (ETDEWEB)

    Perales, A. [Equipos Nucleares, S.A. - Ensa, Jose Ortega y Gasset, 28006 Madrid (Spain); Woolf, G. [Tecnicas Reunidas - TR, Arapiles, 28014 Madrid (Spain)

    2010-07-01

    Equipos Nucleares S.A. (Ensa) and Tecnicas Reunidas S.A. (TR), both long-established Spanish companies, have brought together innovative approaches for the supply of heat transfer solution packages by combining their respective experiences in heat exchanger design (TR), manufacturing (Ensa), and nuclear materials procurement (Ensa and TR), thereby founding a new potent European component supplier for nuclear power plants with over 50 years of experience in the global nuclear market. The combined strategy of the Ensa-TR association which addresses the problems currently faced by nuclear component suppliers is described herein. (authors)

  6. 有效控制建筑工程电气安装造价%Effective Cost Control of Electrical Installation of Construction Engineering

    Institute of Scientific and Technical Information of China (English)

    由晨光

    2014-01-01

    Along with the accelerating of city construction, the city housing construction has also ushered in a new deve-lopment climax. Electrical engineering is an important comp-onent of the housing construction;and the instal ation process is relatively complex. This paper studied the cost of electrical instal ation the construction engineering and put forward some suggestions.%随着我国城市化建设进程的不断加快,城市房屋建筑也迎来了新的发展高潮。电气工程是房屋工程建设的重要组成,其安装过程相对复杂。文章就建筑工程中电气安装造价问题进行了研究,并提出了一些建议。

  7. Engineered barrier development for a nuclear waste repository in basalt: an integration of current knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M.J.

    1980-05-01

    This document represents a compilation of data and interpretive studies conducted as part of the engineered barriers program of the Basalt Waste Isolation Project. The overall objective of these studies is to provide information on barrier system designs, emplacement and isolation techniques, and chemical reactions expected in a nuclear waste repository located in the basalts underlying the Hanford Site within the state of Washington. Backfills, waste-basalt interactions, sorption, borehole plugging, etc., are among the topics discussed.

  8. A method for estimating tokamak poloidal field coil currents which incorporates engineering constraints

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, W.A.

    1990-05-01

    This thesis describes the development of a design tool for the poloidal field magnet system of a tokamak. Specifically, an existing program for determining the poloidal field coil currents has been modified to: support the general case of asymmetric equilibria and coil sets, determine the coil currents subject to constraints on the maximum values of those currents, and determine the coil currents subject to limits on the forces those coils may carry. The equations representing the current limits and coil force limits are derived and an algorithm based on Newton's method is developed to determine a set of coil currents which satisfies those limits. The resulting program allows the designer to quickly determine whether or not a given coil set is capable of supporting a given equilibrium. 25 refs.

  9. Some Problems in Garden Engineering Construction Project Bidding%园林工程建设项目招投标若干问题探讨

    Institute of Scientific and Technical Information of China (English)

    崔思成

    2014-01-01

    Construction project bidding system not only promotes the implementation of the preparatory work before construction, it also strengthens the construction management of engineering projects to a certain extent, and enhances the quality consciousness of construction unit which is of great significance in shortening construction period, standardizing the order of construction site and control ing material price, and so on.%招投标制度不仅推动了施工项目在开工前各项准备工作的落实,在一定程度上也加强了对工程项目的施工管理,增强了施工单位的质量意识,对缩短工程工期、规范施工现场秩序、控制材料价格等方面有非常重要的意义。

  10. Cell-Derived Extracellular Matrix: Basic Characteristics and Current Applications in Orthopedic Tissue Engineering.

    Science.gov (United States)

    Zhang, Weixiang; Zhu, Yun; Li, Jia; Guo, Quanyi; Peng, Jiang; Liu, Shichen; Yang, Jianhua; Wang, Yu

    2016-06-01

    The extracellular matrix (ECM) is a dynamic and intricate microenvironment with excellent biophysical, biomechanical, and biochemical properties, which can directly or indirectly regulate cell proliferation, adhesion, migration, and differentiation, as well as plays key roles in homeostasis and regeneration of tissues and organs. The ECM has attracted a great deal of attention with the rapid development of tissue engineering in the field of regenerative medicine. Tissue-derived ECM scaffolds (also referred to as decellularized tissues and whole organs) are considered a promising therapy for the repair of musculoskeletal defects, including those that are widely used in orthopedics, although there are a few shortcomings. Similar to tissue-derived ECM scaffolds, cell-derived ECM scaffolds also have highly advantageous biophysical and biochemical properties, in particular their ability to be produced in vitro from a number of different cell types. Furthermore, cell-derived ECM scaffolds more closely resemble native ECM microenvironments. The products of cell-derived ECM have a wide range of biomedical applications; these include reagents for cell culture substrates and biomaterials for scaffolds, hybrid scaffolds, and living cell sheet coculture systems. Although cell-derived ECM has only just begun to be investigated, it has great potential as a novel approach for cell-based tissue repair in orthopedic tissue engineering. This review summarizes and analyzes the various types of cell-derived ECM products applied in cartilage, bone, and nerve tissue engineering in vitro or in vivo and discusses future directions for investigation of cell-derived ECM.

  11. Current status of genetic engineering in cotton (Gossypium hirsutum L): an assessment.

    Science.gov (United States)

    Chakravarthy, Vajhala S K; Reddy, Tummala Papi; Reddy, Vudem Dashavantha; Rao, Khareedu Venkateswara

    2014-06-01

    Cotton is considered as the foremost commercially important fiber crop and is deemed as the backbone of the textile industry. The productivity of cotton crop, worldwide, is severely hampered by the occurrence of pests, weeds, pathogens apart from various environmental factors. Several beneficial agronomic traits, viz., early maturity, improved fiber quality, heat tolerance, etc. have been successfully incorporated into cotton varieties employing conventional hybridization and mutation breeding. Crop losses, due to biotic factors, are substantial and may be reduced through certain crop protection strategies. In recent years, pioneering success has been achieved through the adoption of modern biotechnological approaches. Genetically engineered cotton varieties, expressing Bacillus thuringiensis cry genes, proved to be highly successful in controlling the bollworm complex. Various other candidate genes responsible for resistance to insect pests and pathogens, tolerance to major abiotic stress factors such as temperature, drought and salinity, have been introduced into cotton via genetic engineering methods to enhance the agronomic performance of cotton cultivars. Furthermore, genes for improving the seed oil quality and fiber characteristics have been identified and introduced into cotton cultivars. This review provides a brief overview of the various advancements made in cotton through genetic engineering approaches.

  12. Young, southern women's perceptions of STEM careers: Examining science, technology, engineering & mathematics as a gendered construct

    Science.gov (United States)

    Quinton, Jessica Elizabeth

    Career interests develop over a lifetime and tend to solidify during late adolescence and early adulthood (Lent, Brown, and Hackett, 2002). The primary purpose of the present qualitative study, which is framed in Feminist Standpoint Theory (Haraway, 1988; Harding, 2007; Naples, 2007; Richardson, 2007), is to understand how eighth-grade, young women in a suburban, public, southern, middle school the South Carolina County School District (CCSD) (pseudonym) perceive their accessibility to Science, Technology, Engineering, and Mathematics (STEM) courses and careers. The secondary purpose is to understand these young women's "perceptions and unconscious beliefs about gender in science and mathematics" and how their "perceptions and unconscious beliefs about gender" in the STEM fields may impact the careers that these young women may choose in the future (American Association of University Women, 2010, 9). Within the present study, the perceptions of young women who identified as "Interested in Science," "Somewhat Interested in Science" and "Uninterested in Science" were identified. STEM courses and careers are a major emphasis in education today. Increasing the numbers of Americans who pursue STEM careers is a government priority, as these careers will strengthen the economy (AAUW 2010). The present study reveals how young women who are highly motivated, talented students perceive STEM courses and careers and how they are influenced by their experiences, gendered messages, and knowledge of STEM careers. To analyze the data, four of Saldana's (2010) dramaturgical codes were utilized including: 1. OBJectives, or motives; 2. CONflicts the participants faced; 3. TACtics to dealing with obstacles; and 4. ATTitudes toward the setting, others, and the conflict. The InVivo Codes allowed the participants stories to emerge through the set of dramaturgical codes that allowed for viewing the girls' experience sin different ways that added depth to their stories. The young women in

  13. Construction of a cellulase hyper-expression system in Trichoderma reesei by promoter and enzyme engineering

    Directory of Open Access Journals (Sweden)

    Zou Gen

    2012-02-01

    Full Text Available Abstract Background Trichoderma reesei is the preferred organism for producing industrial cellulases. However, a more efficient heterologous expression system for enzymes from different organism is needed to further improve its cellulase mixture. The strong cbh1 promoter of T. reesei is frequently used in heterologous expression, however, the carbon catabolite repressor CREI may reduce its strength by binding to the cbh1 promoter at several binding sites. Another crucial point to enhance the production of heterologous enzymes is the stability of recombinant mRNA and the prevention of protein degradation within the endoplasmic reticulum, especially for the bacteria originated enzymes. In this study, the CREI binding sites within the cbh1 promoter were replaced with the binding sites of transcription activator ACEII and the HAP2/3/5 complex to improve the promoter efficiency. To further improve heterologous expression efficiency of bacterial genes within T. reesei, a flexible polyglycine linker and a rigid α-helix linker were tested in the construction of fusion genes between cbh1 from T. reesei and e1, encoding an endoglucanase from Acidothermus cellulolyticus. Results The modified promoter resulted in an increased expression level of the green fluorescent protein reporter by 5.5-fold in inducing culture medium and 7.4-fold in repressing culture medium. The fusion genes of cbh1 and e1 were successfully expressed in T. reesei under the control of promoter pcbh1m2. The higher enzyme activities and thermostability of the fusion protein with rigid linker indicated that the rigid linker might be more suitable for the heterologous expression system in T. reesei. Compared to the parent strain RC30-8, the FPase and CMCase activities of the secreted enzyme mixture from the corresponding transformant R1 with the rigid linker increased by 39% and 30% at 60°C, respectively, and the reduced sugar concentration in the hydrolysate of pretreated corn stover

  14. [Application of wastewater land treatment technique to the construction of ecological engineering in sand land].

    Science.gov (United States)

    Li, Pei-jun; Wang, Zhi-jiang; Sun, Tie-heng; Tai, Pei-dong; Chang, Shi-jun; Xiong, Xian-zhe; Li, Ying-mei

    2005-05-01

    In this paper studies on the feasibility of harmlessness and resource of wastewater, which was discharged from a thermal power plant, by using slow rate filtration of land treatment technique for the fast recovery of vegetation in the Kubuqi sand land were carried out. The selected arbor, shrub and herbage in the land treatment system were poplar (Populus alba Var. Pyramidalis bunge), seabuckthorn (Hippophae rhamnoides) and sweet clover (Melilotus suaveolens) respectively. Three levels of wastewater hydraulic loading were designed in the field pilot experiment. They were high plot with 3000 mm/a irrigation (H), medium plot with 1500 mm/a irrigation (M) and low plot (L) with small volume of irrigation only used in the period of transplant seedlings. The performance indicate that the purification function of power plant wastewater by pre-treatment through combination of precipitation pool with storage ponds is effective and therefore the effluent after pretreatment can be used to irrigation vegetation. The experiment results show that the volume of tree crown for poplar in H plot and M plot was up to 1.07 and 2.21 times comparing with L plot respectively. The annual yield (dry weight) of sweet clover in H plot and M plot was up to 2.33 and 3.0 times comparing with L plot respectively. The height of seabuckthorn in H zone and M plot was up to 1.08 and 1.32 times comparing with L plot respectively. There is direct proportion between growth status of vegetation and hydraulic loading of irrigation. The contents of heavy metals for sweet clover (Cd 0.021 mg/kg, Pb<0.001 mg/kg, Cr <0.01 mg/kg, As 0.043 mg/kg) are much lower than the food standards of grain and vegetables, therefore the sweet clover for raising livestock is safe. Wastewater in this area is valuable source. Its reasonable utilization can contribute important benefits in economy and ecology in the ecological construction and developing effective agriculture and animal husbandry.

  15. In Vitro Mineralization of an Osteoid-Like Dense Collagen Construct for Bone Tissue Engineering

    Science.gov (United States)

    Marelli, Benedetto

    -seeded constructs. In conclusion, since the role of the collagen framework microstructure on its mineralization has been previously ignored, the present doctoral dissertation provides new insights into collagen mineralization. More significantly, since collagen matrices are difficult to mineralize in vivo, and need to be taken out of physiological boundaries to effect in vitro mineralization, it is predicted that this work will have a significant impact on the production of rapidly implantable and mineralizable constructs for bone regenerative therapy. (Abstract shortened by UMI.)

  16. Value Engineering and Value Management of Construction Project%建设项目的价值工程与价值管理

    Institute of Scientific and Technical Information of China (English)

    方翠兰

    2011-01-01

    "Value Engineering" and "Value Management" are two academic vocabularies emerging in modern times.Value Engineering was originally used in American military field and Value Management was originally used in construction project.Value Engineering and Value Management use relevant principles and methods of management to improve product value of the item.After entering into 21st century, Value Engineering and Value Management more and more are quoted in various industries of the construction project.In recent years, the development of China's construction projects is more and more fast, and construction industry has become the focus of public concern.Both in theory and practice, there is a wide gap of construction project between China and overseas.Engineering construction project is not a simple project.It is needed to optimally use Value Engineering to serve for value management of construction project.This paper introduces relevant content about Value Engineering and Value Management and their application in construction projects in our country.%"价值工程"和"价值管理"是两个在近代才刚刚出现学术性的词汇,价值工程最初被应用在美国的军事方面,价值管理最初被应用在建筑工程上.价值工程和价值管理采用管理学有关的原则和方法,提升产品价值的项目,进入21世纪以来,价值工程和价值管理越来越多的被引用在不同工业领域的建设项目之中.近年来中国的建设项目的发展越来越快,而且建设行业也成为了大众关注的焦点,中国的建设项目,无论在理论和实践上,与国外都有很大的差距,工程建设项目并不是一个简单的项目,我们需要做的是合理利用价值工程的建设项目价值管理服务.本文将介绍价值工程和价值管理的相关内容,以及其在我国建筑工程项目中的应用.

  17. 建筑工程造价预结算审核管理的有效举措%Analysis of the Effective Initiatives of Pre-settlement Audit Management in the Construction Engineering Cost

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      随着经济水平的快速发展,如何在保证建筑工程质量的基础上,对建筑工程的造价进行管理与控制,是当前建筑行业发展过程中所要解决的问题。本文就当前建筑工程造价预结算审核中所存在的问题,提出了有效措施。%With the rapid development of economic level, ho-w to management and control the construction engineering cost on the basis of making sure that the quality of construction is the problem that should be solved in the development pro-cess of the construction industry. In this article, the author puts forward some effective measures for the problems of pre-set-lement audit management in the current construction engine-eering cost.

  18. Current and future regenerative medicine - principles, concepts, and therapeutic use of stem cell therapy and tissue engineering in equine medicine

    DEFF Research Database (Denmark)

    Koch, Thomas Gadegaard; Berg, Lise Charlotte; Betts, Dean H.

    2009-01-01

    This paper provides a bird's-eye perspective of the general principles of stem-cell therapy and tissue engineering; it relates comparative knowledge in this area to the current and future status of equine regenerative medicine.The understanding of equine stem cell biology, biofactors, and scaffolds......, and their potential therapeutic use in horses are rudimentary at present. Mesenchymal stem cell isolation has been proclaimed from several equine tissues in the past few years. Based on the criteria of the International Society for Cellular Therapy, most of these cells are more correctly referred to as multipotent...... factors, and biomaterials - are increasingly being applied in equine medicine, fuelled by better scaffolds and increased understanding of individual biofactors and cell sources.The effectiveness of stem cell-based therapies and most tissue engineering concepts has not been demonstrated sufficiently...

  19. Lithium-ion battery materials and engineering current topics and problems from the manufacturing perspective

    CERN Document Server

    Gulbinska, Malgorzata K

    2014-01-01

    Gaining public attention due, in part,  to their potential application as energy storage devices in cars, Lithium-ion batteries have encountered widespread demand, however, the understanding of lithium-ion technology has often lagged behind production. This book defines the most commonly encountered challenges from the perspective of a high-end lithium-ion manufacturer with two decades of experience with lithium-ion batteries and over six decades of experience with batteries of other chemistries. Authors with years of experience in the applied science and engineering of lithium-ion batterie

  20. Ethanol production from xylose in engineered Saccharomyces cerevisiae strains. Current state and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Matsushika, Akinori; Inoue, Hiroyuki; Sawayama, Shigeki [National Inst. of Advanced Industrial Science and Technology (AIST), Hiroshima (JP). Biomass Technology Research Center (BTRC); Kodaki, Tsutomu [Kyoto Univ. (Japan). Inst. of Advanced Energy

    2009-08-15

    Bioethanol production from xylose is important for utilization of lignocellulosic biomass as raw materials. The research on yeast conversion of xylose to ethanol has been intensively studied especially for genetically engineered Saccharomyces cerevisiae during the last 20 years. S. cerevisiae, which is a very safe microorganism that plays a traditional and major role in industrial bioethanol production, has several advantages due to its high ethanol productivity, as well as its high ethanol and inhibitor tolerance. However, this yeast cannot ferment xylose, which is the dominant pentose sugar in hydrolysates of lignocellulosic biomass. A number of different strategies have been applied to engineer yeasts capable of efficiently producing ethanol from xylose, including the introduction of initial xylose metabolism and xylose transport, changing the intracellular redox balance, and overexpression of xylulokinase and pentose phosphate pathways. In this review, recent progress with regard to these studies is discussed, focusing particularly on xylose-fermenting strains of S. cerevisiae. Recent studies using several promising approaches such as host strain selection and adaptation to obtain further improved xylose-utilizing S. cerevisiae are also addressed. (orig.)

  1. Genetically engineered virus-resistant plants in developing countries: current status and future prospects.

    Science.gov (United States)

    Reddy, D V R; Sudarshana, M R; Fuchs, M; Rao, N C; Thottappilly, G

    2009-01-01

    Plant viruses cause severe crop losses worldwide. Conventional control strategies, such as cultural methods and biocide applications against arthropod, nematode, and plasmodiophorid vectors, have limited success at mitigating the impact of plant viruses. Planting resistant cultivars is the most effective and economical way to control plant virus diseases. Natural sources of resistance have been exploited extensively to develop virus-resistant plants by conventional breeding. Non-conventional methods have also been used successfully to confer virus resistance by transferring primarily virus-derived genes, including viral coat protein, replicase, movement protein, defective interfering RNA, non-coding RNA sequences, and protease, into susceptible plants. Non-viral genes (R genes, microRNAs, ribosome-inactivating proteins, protease inhibitors, dsRNAse, RNA modifying enzymes, and scFvs) have also been used successfully to engineer resistance to viruses in plants. Very few genetically engineered (GE) virus resistant (VR) crops have been released for cultivation and none is available yet in developing countries. However, a number of economically important GEVR crops, transformed with viral genes are of great interest in developing countries. The major issues confronting the production and deregulation of GEVR crops in developing countries are primarily socio-economic and related to intellectual property rights, biosafety regulatory frameworks, expenditure to generate GE crops and opposition by non-governmental activists. Suggestions for satisfactory resolution of these factors, presumably leading to field tests and deregulation of GEVR crops in developing countries, are given.

  2. High Dynamic Magnetic Beam Current Measurements by Means of Optimised Magneto-Resistance (MR) Sensor Engineering

    CERN Document Server

    Hape, M; Ricken, W

    2005-01-01

    The GSI-FAIR project (facility for antiprotons and ion research) will comprehend DC currents up to around 5 A in the SIS 100 synchrotron and after bunch compression down to 50 ns pulse length the peak currents will reach up to 100 A. To meet these higher demands of beam current measurements new sensor techniques are foreseen. The measurement device itself will be designed in form of a clip-on ampere-meter. The air gap of the flux concentrator is assumed to be around 5 mm and thus, the estimated maximum field therein is around 30 mT for a beam current of 100 A peak. The resolution of this device is aimed to be 1 mA in beam current, corresponding to a system dynamic of around 105. This high demands of beam current measurement require more sophisticated sensor types than just using a Hall probe. The characteristics of AMR (anisotropic magneto-resistance), GMR (giant magneto-resistance) and GMI (giant magneto-impedance) sensors like hysteresis, linearity and sensitivity have been measured within the magnetic fiel...

  3. Research on Application Strategy of EPC Model in Military Engineering Construction%EPC模式在军队工程建设中的应用策略研究

    Institute of Scientific and Technical Information of China (English)

    邓安仲; 王群; 李云涛

    2016-01-01

    基于目前军队工程建设的现状,对军队工程引入EPC模式的必要性以及应用EPC模式存在的问题进行分析,提出明确军队工程EPC模式应用范围、完善军队工程项目组织实施制度、建立健全风险管理体系等应对策略,为军队工程改革项目管理模式提供借鉴。%On basis of the current situation of the military engineering construction,this paper analyzes the necessity of introducing the EPC model into military engineering and the problems existing in the application of EPC model. Then,puts forward the coping strategies,including defining the application scope of the military engineering EPC model,improving the organization system of military engineering project,establishing and perfecting the risk management system,in order to provide reference for the military engineering reform project management model.

  4. Constructing an Evidence-Base for Future CALL Design with "Engineering Power": The Need for More Basic Research and Instrumental Replication

    Science.gov (United States)

    Handley, Zöe

    2014-01-01

    This paper argues that the goal of Computer-Assisted Language Learning (CALL) research should be to construct a reliable evidence-base with "engineering power" and generality upon which the design of future CALL software and activities can be based. In order to establish such an evidence base for future CALL design, it suggests that CALL…

  5. 浅析公路工程施工招标资格审查标准%Brief Analysis on Bidding Qualification Examination Standard of Highway Engineering Construction

    Institute of Scientific and Technical Information of China (English)

    高新

    2012-01-01

    通过招标实例,对公路工程施工资格审查标准中各评分因素进行详细分析解释。%Through the practical bidding cases,all evaluation factors in the qualification examination standard of highway engineering construction are analyzed and explained in detail.

  6. Constructively aligned teaching and learning in higher education in engineering: what do students perceive as contributing to the learning of interdisciplinary thinking?

    NARCIS (Netherlands)

    Spelt, E.J.H.; Luning, P.A.; Boekel, van M.A.J.S.; Mulder, M.

    2014-01-01

    Increased attention to the need for constructively aligned teaching and learning in interdisciplinary higher education in engineering is observed. By contrast, little research has been conducted on the implementation of the outcome-based pedagogical approach to interdisciplinary higher education in

  7. Construction of the Electronic Engineering Appling Training Center%电子工程应用训练中心的建设

    Institute of Scientific and Technical Information of China (English)

    李国辉; 葛海波

    2015-01-01

    This paper introdnces the experiences on constructing of the electronic engineering applying training cen-ter in the college of electronic engineering of Xi'an university of posts and telecommunications,the building project of the engineering training center with electronic information characteristics is described in detail. The project re-volves around the demand guide,engineering application and innovative practice educational philosophy and the engineering cognitive ability,engineering experimental ability,engineering designing ability,and engineering im-plementing ability mainstream. The building project has made remarkable achievements since it carried out three years ago.%本文介绍我院三年来电子工程应用训练中心建设的经验,详细阐述了具有电子信息特色的工程训练中心建设方案。该方案围绕需求引导、工程应用和创新实践的教育理念,以工程认知能力、工程实验能力、工程设计能力和工程实施能力为主线进行规划。建设方案实施三年来,效果显著。

  8. Current state of nuclear fuel cycles in nuclear engineering and trends in their development according to the environmental safety requirements

    Science.gov (United States)

    Vislov, I. S.; Pischulin, V. P.; Kladiev, S. N.; Slobodyan, S. M.

    2016-08-01

    The state and trends in the development of nuclear fuel cycles in nuclear engineering, taking into account the ecological aspects of using nuclear power plants, are considered. An analysis of advantages and disadvantages of nuclear engineering, compared with thermal engineering based on organic fuel types, was carried out. Spent nuclear fuel (SNF) reprocessing is an important task in the nuclear industry, since fuel unloaded from modern reactors of any type contains a large amount of radioactive elements that are harmful to the environment. On the other hand, the newly generated isotopes of uranium and plutonium should be reused to fabricate new nuclear fuel. The spent nuclear fuel also includes other types of fission products. Conditions for SNF handling are determined by ecological and economic factors. When choosing a certain handling method, one should assess these factors at all stages of its implementation. There are two main methods of SNF handling: open nuclear fuel cycle, with spent nuclear fuel assemblies (NFAs) that are held in storage facilities with their consequent disposal, and closed nuclear fuel cycle, with separation of uranium and plutonium, their purification from fission products, and use for producing new fuel batches. The development of effective closed fuel cycles using mixed uranium-plutonium fuel can provide a successful development of the nuclear industry only under the conditions of implementation of novel effective technological treatment processes that meet strict requirements of environmental safety and reliability of process equipment being applied. The diversity of technological processes is determined by different types of NFA devices and construction materials being used, as well as by the composition that depends on nuclear fuel components and operational conditions for assemblies in the nuclear power reactor. This work provides an overview of technological processes of SNF treatment and methods of handling of nuclear fuel

  9. Microbial Fuel Cell Cathodes With Poly(dimethylsiloxane) Diffusion Layers Constructed around Stainless Steel Mesh Current Collectors

    KAUST Repository

    Zhang, Fang

    2010-02-15

    A new and simplified approach for making cathodes for microbial fuel cells (MFCs) was developed by using metal meshcurrent collectorsandinexpensive polymer/carbon diffusion layers (DLs). Rather than adding a current collector to a cathode material such as carbon cloth, we constructed the cathode around the metal mesh itself, thereby avoiding the need for the carbon cloth or other supporting material. A base layer of poly(dimethylsiloxane) (PDMS) and carbon black was applied to the air-side of a stainless steel mesh, and Pt on carbon black with Nafion binder was applied to the solutionside as catalyst for oxygen reduction. The PDMS prevented water leakage and functioned as a DL by limiting oxygen transfer through the cathode and improving coulombic efficiency. PDMS is hydrophobic, stable, and less expensive than other DL materials, such as PTFE, that are commonly applied to air cathodes. Multiple PDMS/carbon layers were applied in order to optimize the performance of the cathode. Two PDMS/ carbon layers achieved the highest maximum power density of 1610 ± 56 mW/m 2 (normalized to cathode projected surface area; 47.0 ± 1.6 W/m3 based on liquid volume). This power output was comparable to the best result of 1635 ± 62 mW/m2 obtained using carbon cloth with three PDMS/carbon layers and a Pt catalyst. The coulombic efficiency of the mesh cathodes reached more than 80%, and was much higher than the maximum of 57% obtained with carbon cloth. These findings demonstrate that cathodes can be constructed around metal mesh materials such as stainless steel, and that an inexpensive coating of PDMS can prevent water leakage and lead to improved coulombic efficiencies. © 2010 American Chemical Society.

  10. Enhanced nutrient transport improves the depth-dependent properties of tri-layered engineered cartilage constructs with zonal co-culture of chondrocytes and MSCs.

    Science.gov (United States)

    Kim, Minwook; Farrell, Megan J; Steinberg, David R; Burdick, Jason A; Mauck, Robert L

    2017-08-01

    Biomimetic design in cartilage tissue engineering is a challenge given the complexity of the native tissue. While numerous studies have generated constructs with near-native bulk properties, recapitulating the depth-dependent features of native tissue remains a challenge. Furthermore, limitations in nutrient transport and matrix accumulation in engineered constructs hinders maturation within the central core of large constructs. To overcome these limitations, we fabricated tri-layered constructs that recapitulate the depth-dependent cellular organization and functional properties of native tissue using zonally derived chondrocytes co-cultured with MSCs. We also introduced porous hollow fibers (HFs) and HFs/cotton threads to enhance nutrient transport. Our results showed that tri-layered constructs with depth-dependent organization and properties could be fabricated. The addition of HFs or HFs/threads improved matrix accumulation in the central core region. With HF/threads, the local modulus in the deep region of tri-layered constructs nearly matched that of native tissue, though the properties in the central regions remained lower. These constructs reproduced the zonal organization and depth-dependent properties of native tissue, and demonstrate that a layer-by-layer fabrication scheme holds promise for the biomimetic repair of focal cartilage defects. Articular cartilage is a highly organized tissue driven by zonal heterogeneity of cells, extracellular matrix proteins and fibril orientations, resulting in depth-dependent mechanical properties. Therefore, the recapitulation of the functional properties of native cartilage in a tissue engineered construct requires such a biomimetic design of the morphological organization, and this has remained a challenge in cartilage tissue engineering. This study demonstrates that a layer-by-layer fabrication scheme, including co-cultures of zone-specific articular CHs and MSCs, can reproduce the depth-dependent characteristics

  11. Compulsory Checking of Nuclear Power Engineering Materials by Direct and Eddy Current

    Science.gov (United States)

    Larionov, V. V.; Lider, A. M.; Sednev, D. A.; Xu, Shupeng

    2016-08-01

    The testing technology of copper parts designed for dry storage of spent nuclear fuel with application of direct and eddy current has been developed. Measurements results of flaw quantity caused hydrogenation and oxidation processes are presented. Evolution of copper M 001 flaw structure during hydrogenation from gaseous medium is analyzed. It has been demonstrated that the dependence of copper p electrical resistance on number of flaws in its structure has dome shaped character and changes with eddy current frequency change. Number of flaws formed by hydrogen depends on direction (100) or (200) of the crystal structure of copper lattice.

  12. On management and control over construction progress in civil engineering programs%土建工程的施工进度管理和控制

    Institute of Scientific and Technical Information of China (English)

    刘斌

    2015-01-01

    The paper analyzes the factors influencing the construction progress management of civil engineering projects,and points out some sug-gestions for the preparation before the construction,compilation progress plan,and improvement of management regulations,so as to promote the construction progress management level of the civil engineering projects.%分析了影响土建工程施工进度管理的各项因素,针对施工进度管理中存在的问题,提出了做好开工前的准备工作、编制进度计划、完善项目管理法规体系等建议,以有效提高土建工程施工进度管理水平。

  13. Cost optimization of Modularization Construction in Offshore Engineering%论海洋工程模块化建造的成本优化

    Institute of Scientific and Technical Information of China (English)

    赫宝春

    2014-01-01

    海洋工程模块化建造比较于传统的海洋工程建造模式,在材料使用、设备投入、人工投入等方面均有明显的优势,使得建造效率更高、成本更低,势必将成为未来海洋工程建造的主流趋势。%Compared with traditional offshore engineering construction method, modularized construction makes efficiency higher and cost lower, because of having obvious advantages in materials, equipment, human labor and other aspects. Modularized construction will become the main trend in offshore engineering.

  14. Design and Construction of Artificial Extracellular Matrix (aECM) Proteins from Escherichia coli for Skin Tissue Engineering.

    Science.gov (United States)

    Low, Pearlie S J; Tjin, Monica S; Fong, Eileen

    2015-06-11

    Recombinant technology is a versatile platform to create novel artificial proteins with tunable properties. For the last decade, many artificial proteins that have incorporated functional domains derived from nature (or created de novo) have been reported. In particular, artificial extracellular matrix (aECM) proteins have been developed; these aECM proteins consist of biological domains taken from fibronectin, laminins and collagens and are combined with structural domains including elastin-like repeats, silk and collagen repeats. To date, aECM proteins have been widely investigated for applications in tissue engineering and wound repair. Recently, Tjin and coworkers developed integrin-specific aECM proteins designed for promoting human skin keratinocyte attachment and propagation. In their work, the aECM proteins incorporate cell binding domains taken from fibronectin, laminin-5 and collagen IV, as well as flanking elastin-like repeats. They demonstrated that the aECM proteins developed in their work were promising candidates for use as substrates in artificial skin. Here, we outline the design and construction of such aECM proteins as well as their purification process using the thermo-responsive characteristics of elastin.

  15. Design, construction and mechanical testing of digital 3D anatomical data-based PCL-HA bone tissue engineering scaffold.

    Science.gov (United States)

    Yao, Qingqiang; Wei, Bo; Guo, Yang; Jin, Chengzhe; Du, Xiaotao; Yan, Chao; Yan, Junwei; Hu, Wenhao; Xu, Yan; Zhou, Zhi; Wang, Yijin; Wang, Liming

    2015-01-01

    The study aims to investigate the techniques of design and construction of CT 3D reconstructional data-based polycaprolactone (PCL)-hydroxyapatite (HA) scaffold. Femoral and lumbar spinal specimens of eight male New Zealand white rabbits were performed CT and laser scanning data-based 3D printing scaffold processing using PCL-HA powder. Each group was performed eight scaffolds. The CAD-based 3D printed porous cylindrical stents were 16 piece × 3 groups, including the orthogonal scaffold, the Pozi-hole scaffold and the triangular hole scaffold. The gross forms, fiber scaffold diameters and porosities of the scaffolds were measured, and the mechanical testing was performed towards eight pieces of the three kinds of cylindrical scaffolds, respectively. The loading force, deformation, maximum-affordable pressure and deformation value were recorded. The pore-connection rate of each scaffold was 100 % within each group, there was no significant difference in the gross parameters and micro-structural parameters of each scaffold when compared with the design values (P > 0.05). There was no significant difference in the loading force, deformation and deformation value under the maximum-affordable pressure of the three different cylinder scaffolds when the load was above 320 N. The combination of CT and CAD reverse technology could accomplish the design and manufacturing of complex bone tissue engineering scaffolds, with no significant difference in the impacts of the microstructures towards the physical properties of different porous scaffolds under large load.

  16. Changes in soil hydraulic properties caused by construction of a simulated waste trench at the Idaho National Engineering Laboratory, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Shakofsky, S.

    1995-03-01

    In order to assess the effect of filled waste disposal trenches on transport-governing soil properties, comparisons were made between profiles of undisturbed soil and disturbed soil in a simulated waste trench. The changes in soil properties induced by the construction of a simulated waste trench were measured near the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory (INEL) in the semiarid southeast region of Idaho. The soil samples were collected, using a hydraulically-driven sampler to minimize sample disruption, from both a simulated waste trench and an undisturbed area nearby. Results show that the undisturbed profile has distinct layers whose properties differ significantly, whereas the soil profile in the simulated waste trench is, by comparison, homogeneous. Porosity was increased in the disturbed cores, and, correspondingly, saturated hydraulic conductivities were on average three times higher. With higher soil-moisture contents (greater than 0.32), unsaturated hydraulic conductivities for the undisturbed cores were typically greater than those for the disturbed cores. With lower moisture contents, most of the disturbed cores had greater hydraulic conductivities. The observed differences in hydraulic conductivities are interpreted and discussed as changes in the soil pore geometry.

  17. Proposal for the award of an industrial services contract for civil engineering superstructure and internal construction building work

    CERN Document Server

    2001-01-01

    This document concerns the award of an Industrial Services contract for civil engineering superstructure and internal construction building work. Following a market survey carried out among 112 firms in fifteen Member States, a call for tenders (IT-2546/ST/Rev.) was sent on 12 April 2001 to eleven consortia, four consisting of four firms, three consisting of three firms and four consisting of two firms, in seven Member States. By the closing date, CERN had received tenders from eight consortia in six Member States. The Finance Committee is invited to agree to the negotiation of a contract with the consortium SPIE CITRA SUD-EST(FR)-ANTIRUST TECHNOLOGY (GR), the lowest bidder, for an initial period of three years from 1 January 2002 for an amount not exceeding 15 375 000 Swiss francs, not subject to revision. The contract will include options for two one-year extensions beyond the initial three-year period. The consortium has indicated the following distribution by country of the contract value covered by this ...

  18. Risk Management on Railroad Engineering Project Construction%铁路工程项目施工风险分析

    Institute of Scientific and Technical Information of China (English)

    陈棉; 赵延龙; 莫俊文

    2013-01-01

      在我国铁路的不断发展过程中,需要对其施工风险进行研究。以临沂至临沭铁路项目为例,构建三层铁路项目风险指标体系进行风险的识别。用层次分析法对该项目进行风险分析,找出其中的主要风险,为项目风险决策提供依据,并指出本项目应重点防范的风险及具体应对措施。%With China's high-speed rail development, it is necessary to research on its construction risk. The article uses the fault tree to indentify the risk of LingXin to LingShu high-speed rail engineering, builds a three-tier risk index system of railway project risk identification. With the analytic hierarchy process, it finds out the main risk, for project risk decision provides the basis, and points out the key risks that should be concerned and the specific response.

  19. High Power Laser Science and Engineering Design and current progress of the Apollon 10 PW project

    OpenAIRE

    ZOU, J-P; Le Blanc, C; Dimitrios PAPADOPOULOS; Chériaux, G; Georges, Patrick; Mennerat, G.; Druon, Frédéric; Lecherbourg, L.; Pellegrina, A; Ramirez, Philippe; Giambruno, F; Fréneaux, A; Leconte, F; Badarau, D; Boudenne, J. M

    2015-01-01

    International audience; The objective of the Apollon project is the generation of 10 PW peak power pulses of 15 fs at 1 shot/minute. In this paper the Apollon facility design, the technological challenges and the current progress of the project will be presented.

  20. Theoretical Grounds of Economic Assessment of the Current Level of Innovation Receptivity of Engineering Enterprises

    Directory of Open Access Journals (Sweden)

    Yemelianov Oleksandr Yu.

    2014-03-01

    Full Text Available The article studies and generalises existing approaches to identification of criteria of assessment of innovation receptivity of subjects of economic activity and also marks out main groups of methods of this assessment. It provides a chain of competences of an enterprise in the sphere of management of its innovation activity, which meets its passive and active innovation receptivity, which lies in the foundation of formation of the multiplicative approach to assessment of the current level of innovation receptivity of an enterprise. The article offers complex qualitative and quantitative indicators of active and also passive innovation receptivity of an enterprise. Further studies of the issue of assessment of the current level of innovation receptivity of economic subjects require clarification of capabilities of a more complete consideration of influence of the obtained financial results from the enterprise innovation activity upon this level.

  1. English-Lithuanian-English Machine Translation lexicon and engine: current state and future work

    CERN Document Server

    Barisevičius, G

    2011-01-01

    This article overviews the current state of the English-Lithuanian-English machine translation system. The first part of the article describes the problems that system poses today and what actions will be taken to solve them in the future. The second part of the article tackles the main issue of the translation process. Article briefly overviews the word sense disambiguation for MT technique using Google.

  2. Integrated Computational Materials Engineering of Titanium: Current Capabilities Being Developed Under the Metals Affordability Initiative

    Science.gov (United States)

    Glavicic, M. G.; Venkatesh, V.

    2014-07-01

    A technical review of the titanium model development programs currently funded under the Metals Affordability Initiative is presented. Progress of the "Advanced Titanium Alloy Microstructure and Mechanical Property Modeling" and "ICME of Microtexture Evolution and its Effect on Cold Dwell/High/Low Cycle Fatigue Behavior of Dual Phase Titanium Alloys" will be reviewed followed by a discussion of the future modeling needs of the aerospace industry.

  3. Factors that Influence Female Folk to engage in Building and Civil Engineering Construction Site Work in Nigeria – a case Study of Isoko Women

    Directory of Open Access Journals (Sweden)

    O. Osubor (Fniqs, Rqs

    2016-11-01

    Full Text Available From early times, building and civil engineering construction has been a male dominated industry. But in today’s contemporary times, the women folk have broken this monotony of male domination. This is evident in the building and engineering industry. Isoko land in the south of Delta State, although women have broken from the stereotype of home keeping into construction, their level of engagement is at the lowest ebb as casual and unskilled workers. This study looks at the factors that encourage female to engage in construction especially at the lowest ebb and the implications for the woman, society, and construction industry. Oral interview methodology was adopted in this study. The response of five local contractors/employers and 60 women interviewed at construction site formed the data for this study. A simple percentage was used to analyze data generated. Findings reveal that poverty and unemployment, lack of education and skill, family responsibility and environmental factors top the reasons. Policies that encourage and make it mandatory for women to progress in education and skill acquisition, provide a future for women in construction and stop discrimination against women will be a step in the right direction. Such policies are recommended.

  4. The influence factors of construction engineering cost and the strategy to reduce engineering cost%建筑工程造价的影响要素及降低工程造价的策略

    Institute of Scientific and Technical Information of China (English)

    陈华荣

    2014-01-01

    This paper introduced in detail the construction engineering cost,and analyzed the human factors,policy factors,market factors,con-struction factors influence of engineering cost,and put forward specific strategies to reduce the engineering cost,to improve the economic benefits of whole engineering.%对建筑工程造价进行了详细的介绍,并对影响工程造价的人为要素、政策要素、市场要素、施工要素进行了分析,进而提出了降低工程造价的具体策略,以提升整个工程的经济效益。

  5. Constructive Ontology Engineering

    Science.gov (United States)

    Sousan, William L.

    2010-01-01

    The proliferation of the Semantic Web depends on ontologies for knowledge sharing, semantic annotation, data fusion, and descriptions of data for machine interpretation. However, ontologies are difficult to create and maintain. In addition, their structure and content may vary depending on the application and domain. Several methods described in…

  6. Constructive Ontology Engineering

    Science.gov (United States)

    Sousan, William L.

    2010-01-01

    The proliferation of the Semantic Web depends on ontologies for knowledge sharing, semantic annotation, data fusion, and descriptions of data for machine interpretation. However, ontologies are difficult to create and maintain. In addition, their structure and content may vary depending on the application and domain. Several methods described in…

  7. Construction project of Flamanville 3 NPP. The participation of Iberdrola engineering and Construction; El proyecto de construccion de la central nuclear de Flamanville 3. La participacion de Iberdrola Ingenieria y Construccion

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Prada, J. I.; Cubian, B.

    2014-10-01

    Iberdrola Engineering and Construction (IIC) leads several projects mini EPC for the EPR Flamanville 3 NPP for providing important for safety components and auxiliary systems in the pump house and in the turbine island. The realization of this new nuclear project has been a challenge from the technical and organizational perspective because the plant is the first of the new nuclear station (FDAKE) type EPR 1700 MWe series in a highly restrictive environment due to to the large number of particular requirements from the final customer and the meager degree of progress of the design to the date of commencement of construction. (Author)

  8. The healing of bony defects by cell-free collagen-based scaffolds compared to stem cell-seeded tissue engineered constructs.

    LENUS (Irish Health Repository)

    Lyons, Frank G

    2010-12-01

    One of the key challenges in tissue engineering is to understand the host response to scaffolds and engineered constructs. We present a study in which two collagen-based scaffolds developed for bone repair: a collagen-glycosaminoglycan (CG) and biomimetic collagen-calcium phosphate (CCP) scaffold, are evaluated in rat cranial defects, both cell-free and when cultured with MSCs prior to implantation. The results demonstrate that both cell-free scaffolds showed excellent healing relative to the empty defect controls and somewhat surprisingly, to the tissue engineered (MSC-seeded) constructs. Immunological analysis of the healing response showed higher M1 macrophage activity in the cell-seeded scaffolds. However, when the M2 macrophage response was analysed, both groups (MSC-seeded and non-seeded scaffolds) showed significant activity of these cells which are associated with an immunomodulatory and tissue remodelling response. Interestingly, the location of this response was confined to the construct periphery, where a capsule had formed, in the MSC-seeded groups as opposed to areas of new bone formation in the non-seeded groups. This suggests that matrix deposited by MSCs during in vitro culture may adversely affect healing by acting as a barrier to macrophage-led remodelling when implanted in vivo. This study thus improves our understanding of host response in bone tissue engineering.

  9. 建筑工程测量施工技术探究%Explore the Construction Technique of Building Engineering Survey

    Institute of Scientific and Technical Information of China (English)

    郑志华

    2014-01-01

    This article base on the construction engineering measurement technology, which include two aspects of engin-eering survey technology and influence factor, and then elabo-rates the theory technology and basic methods of measuring construction. The author explains the lofting laid method of a building pilar and high standard control technology in detail, and further discusses the computer application of construction engineering surveying in the end.%本文结合建筑工程测量技术,包括工程测量技术和影响因素两方面。概述了测量施工理论技术及基本方法,具体根据一建筑立柱的放样铺设方法和高标控制技术进行了详细说明。最后,对工程测量施工计算机技术应用做了进一步探讨。

  10. The potential of 3-dimensional construct engineered from poly(lactic-co-glycolic acid)/fibrin hybrid scaffold seeded with bone marrow mesenchymal stem cells for in vitro cartilage tissue engineering.

    Science.gov (United States)

    Abdul Rahman, Rozlin; Mohamad Sukri, Norhamiza; Md Nazir, Noorhidayah; Ahmad Radzi, Muhammad Aa'zamuddin; Zulkifly, Ahmad Hafiz; Che Ahmad, Aminudin; Hashi, Abdurezak Abdulahi; Abdul Rahman, Suzanah; Sha'ban, Munirah

    2015-08-01

    Articular cartilage is well known for its simple uniqueness of avascular and aneural structure that has limited capacity to heal itself when injured. The use of three dimensional construct in tissue engineering holds great potential in regenerating cartilage defects. This study evaluated the in vitro cartilaginous tissue formation using rabbit's bone marrow mesenchymal stem cells (BMSCs)-seeded onto poly(lactic-co-glycolic acid) PLGA/fibrin and PLGA scaffolds. The in vitro cartilaginous engineered constructs were evaluated by gross inspection, histology, cell proliferation, gene expression and sulphated glycosaminoglycan (sGAG) production at week 1, 2 and 3. After 3 weeks of culture, the PLGA/fibrin construct demonstrated gross features similar to the native tissue with smooth, firm and glistening appearance, superior histoarchitectural and better cartilaginous extracellular matrix compound in concert with the positive glycosaminoglycan accumulation on Alcian blue. Significantly higher cell proliferation in PLGA/fibrin construct was noted at day-7, day-14 and day-21 (p<0.05 respectively). Both constructs expressed the accumulation of collagen type II, collagen type IX, aggrecan and sox9, showed down-regulation of collagen type I as well as produced relative sGAG content with PLGA/fibrin construct exhibited better gene expression in all profiles and showed significantly higher relative sGAG content at each time point (p<0.05). This study suggested that with optimum in vitro manipulation, PLGA/fibrin when seeded with pluripotent non-committed BMSCs has the capability to differentiate into chondrogenic lineage and may serve as a prospective construct to be developed as functional tissue engineered cartilage.

  11. Simple engineering design for complex thermoelectric generators based on reduced current approach

    DEFF Research Database (Denmark)

    Wijesooriyage, Waruna Dissanayaka; Rezaniakolaei, Alireza; Rosendahl, Lasse

    2015-01-01

    Thermoelectric generators (TEGs) are niche candidate for the field of energy management as electrical generator devices. Generally, comprehensive and accurate design techniques for TEGs (thermoelectric generators), such as reduced current approach (RCA), are complex and time consuming processes....... This study develops a simple, comprehensive and accurate TEG designing technique based on RCA. The proposed method can predict the most efficient TEG architecture with more than 97% accuracy comparing to the RCA over wide range of possible temperature and zT for present TEG applications. Moreover...

  12. Maize provitamin A carotenoids, current resources and future metabolic engineering challenges.

    Directory of Open Access Journals (Sweden)

    Eleanore T Wurtzel

    2012-02-01

    Full Text Available Vitamin A deficiency is a serious global health problem that can be alleviated by improved nutrition. Development of cereal crops with increased provitamin A carotenoids can provide a sustainable solution to eliminating vitamin A deficiency worldwide. Maize is a model for cereals and a major staple carbohydrate source. Here, we discuss maize carotenogenesis with regard to pathway regulation, available resources, and current knowledge for improving carotenoid content and levels of provitamin A carotenoids in edible maize endosperm. This knowledge will be applied to improve the nutritional composition of related Poaceae crops. We discuss opportunities and challenges for optimizing provitamin A carotenoid biofortification of cereal food crops.

  13. 浅议BI M技术对建设工程质量的影响%The Inlfuence of BIM Technique on the Quality of Construction Engineering

    Institute of Scientific and Technical Information of China (English)

    于琳

    2014-01-01

    建筑信息模型(Building Information Modeling,简称BIM)是一种全新的建筑理念和技术,住房和城乡建设部明确将加快建筑信息模型在工程中的应用列入“十二五”建筑业信息化发展纲要的总体目标。本文结合有关文献,介绍了BIM在国内外的发展趋势及BIM在国内的应用现状,并结合案例,进一步分析BIM对建设工程质量带来的影响,最终得出BIM技术能促进工程质量精细化管理的结论。%Building information modeling(BIM)is a new technique of construction engineering. The ministry of housing and urban-rural development definitely says the overall goal of 12th five-year plan is to accelerate the construction engineering to use building information modeling. Combined with the literature, this paper introduces the trends of BIM technique at home and abroad and the status of BIM application in China. Also,combined with engineering cases,the paper analyze the influence of BIM technique on the quality of construction engineering. Finally,the paper concludes that BIM technique helps the delicacy management of the quality of construction engineering.

  14. 谈公路工程施工进度与施工质量的关系%Discussion on the relation between highway engineering construction schedule and construction quality

    Institute of Scientific and Technical Information of China (English)

    王建生

    2012-01-01

    从工程建设中施工质量和进度的重要性入手,分析了公路工程项目中施工进度和质量的关系,并针对如何处理好质量与进度的关系进行了探讨,为创造高质量、高速度、高效益的精品工程奠定了理论基础。%To begin with the significance of engineering construction quality and schedule,the paper analyzes the relation between highway engineering project constructions schedule and quality,and explores how to do with the relation between the quality and schedule,which has laid theoretical foundation for creating fine projects with high quality,high speed,and high efficiency.

  15. The Necessity to Strengthen the Construction Materials Management of Construction Engineering%加强建筑工程施工材料管理的必要性

    Institute of Scientific and Technical Information of China (English)

    杜军

    2014-01-01

    In recent years, with people’s increasing demand for construction, the construction industry has become a pilar industry of Chinese economy. No mater what kind of constr-uction projects, it requires the use of building materials for construction. Whether the construction materials management measures properly or not, it not only affects the overall con-struction quality, but also affects the project construction cost and time of the next phase ofwork.%近年来,随着人们对建筑的需求增多,建筑行业已经成为我国经济产业中支柱性产业。不论何种建筑工程,都需要使用建筑材料来进行施工,施工材料管理措施是否得当,不仅影响到整体施工质量,也会影响到工程施工成本及下一期工作的开展时间。

  16. Changes in permafrost ecosystem under the influences of human engineering activities and its enlightenment to railway construction

    Institute of Scientific and Technical Information of China (English)

    WANG Genxu; YAO Jinzhong; GUO Zhenggang; WU Qingbo; WANG Yibo

    2004-01-01

    Through the investigations of sample belt transects and sample quadrats, the variation characteristics of the disturbed ecosystem by highway engineering in the permafrost region along the Qinghai-Tibet highway line were studied from the ecological elements such as permafrost ecosystem, community type, biodiversity and biological productivity and biological habitat conditions including soil environmental conditions and permafrost environmental conditions. The results show that in the sense of biology the restoration of high-cold steppe ecosystem was much better than that of high-cold meadow ecosystem after nearly 25 a of natural reconversion. This is mainly manifested in several respects: The dominant plant species of the high-cold steppe have occurred or even held a predominant position; local zonal biodiversity and population abundance have reached or even exceeded the level of the undisturbed natural steppe system. Viewed from soil environment change, organic matter content in the disturbed high-cold steppe on an average decreased by 61.5% and total N content decreased by52.51%, but the nutrient regime of surface soil layer in most of the region corresponded to that of main grassland soil types in the arid region, which is favourable to the growth of cold-resistant species. The mean nutrient contents of the disturbed high-cold meadow soil (Gelic cambosols) were higher than those of natural cryic aridsols. The maintenance of the integrity of meadow soil structure is crucial to the restoration of high-cold meadow ecosystem. However, the distribution and maintenance of high-cold meadow ecosystem were closely related to the permafrost environment, the restoration degree of the disturbed high-cold steppe ecosystem did not show an obvious restrictive relation with permafrost environment. Once the permafrost environment was destroyed by the engineering activities, the high-cold meadow ecosystem was very difficult to rehabilitate. From the comparison of the variation

  17. 土木工程中混凝土施工技术分析%Analysis of the Concrete Construction Technology in Civil Engineering

    Institute of Scientific and Technical Information of China (English)

    王小平

    2013-01-01

    In the building construction process, the choice of materials is extremely strict. The material quality is good or bad is often directly determines the quality of construction wo-rk. The essay analyzes the construction technology of civil en-gineering concrete and summarizes some useful suggestions to improve the quality of construction.%  在建筑工程施工过程中,选用的材料是异常严格的。材料质量好坏往往直接决定了建筑工程的质量。本文对土木工程中混凝土施工技术进行分析,总结了一些提高建筑工程质量的有效建议。

  18. 煤仓滑模工程施工质量控制%Construction quality control of bunker slip form engineering

    Institute of Scientific and Technical Information of China (English)

    李维华

    2012-01-01

    结合马家岩煤矿煤仓项目工程筒壁及附壁的滑模施工实例,对钢筋、预埋件、支撑杆、混凝土、模板的滑升、混凝土的脱模与养护、滑模施工的精度控制等过程进行了质量控制,确保了煤仓滑模的施工质量。%Combining with the slip form construction example of cylinder and attached arm of Majiayan coal mine bunker project engineering, the thesis seriously controls the construction quality of steel, embed members, bearing pile, concrete and formwork slip, concrete demoulding and maintenance and slip form construction accuracy and so on. As a result, it ensures the construction quality of the bunker slip form.

  19. 园林工程项目施工进度管理研究%Study on Construction Schedule Management of Landscape Engineering Project

    Institute of Scientific and Technical Information of China (English)

    樊松丽; 李梅

    2013-01-01

    分析园林工程施工特点,总结施工进度影响因素,提出园林工程施工进度管理目标和内容,指出为保证施工进度管理目标顺利实现,必须做好事前计划、事中控制、事后补救,采取有效的进度管理方法。%This paper analysed the construction characteristics of landscape engineering ,construction progress influencing factors were summarized.Target and content of construction schedule management were proposed.In order to ensure the realization of construction schedule management goals , schedule plan must be made beforehand and controlled during the matter and help after the mat -ter.Relevant schedule management method should be taken.

  20. 绿色施工理论在装饰装修工程施工管理中的应用研究%Application of the Green Construction Theory in Decoration Engineering Construction Management

    Institute of Scientific and Technical Information of China (English)

    田勇

    2013-01-01

    随着我国经济的发展,可持续战略的实施,室内装修的绿色施工理论引起了越来越多的业主的注意。他们不但是追求房屋的装饰装修的美观、大方,而且更加注重装饰装修过程中的绿色环保。只有绿色的可持续的装饰装修施工,才能真正的打造健康、可持续的家居环境。本文主要围绕绿色施工的相关理论展开讨论,重点分析了目前我国在装饰装修工程施工管理中面临的问题,绿色施工理论在装饰装修施工工程中的实现途径及其在装饰装修工程施工管理中的具体应用。%With the development of our national economy, the implementation of sustainable strategy, green construction th-eory of interior decoration caused more and more at ention of the owners. They not only pursue the beautiful and generous of housing decoration, and pay more at ention to the green env-ironmental protection decoration process. Only the green and sustainable decoration construction can real y create a healthy, sustainable home furnishing environment. This paper focuses on the theory of green construction, focusing on problems in the construction management of decoration engineering, ways of green construction theory in the decoration construction pr-ojects and the implementation and practical application in con-struction management of decoration engineering.