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

Code of Federal Regulations, 2013 CFR

2013-10-01

... 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. The...

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

Code of Federal Regulations, 2014 CFR

2014-10-01

... 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. The...

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

Code of Federal Regulations, 2011 CFR

2011-10-01

... 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. The...

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

Code of Federal Regulations, 2012 CFR

2012-10-01

... 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. The...

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

Code of Federal Regulations, 2011 CFR

2011-10-01

... 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. No...

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

Code of Federal Regulations, 2010 CFR

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. The...

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

Code of Federal Regulations, 2013 CFR

2013-10-01

... 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. As required by FAR...

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

Code of Federal Regulations, 2010 CFR

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. No...

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

Code of Federal Regulations, 2012 CFR

2012-10-01

... 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. No...

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

Code of Federal Regulations, 2014 CFR

2014-10-01

... 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. No...

Mechanical preconditioning enables electrophysiologic coupling of skeletal myoblast cells to myocardium

PubMed Central

Treskes, Philipp; Cowan, Douglas B.; Stamm, Christof; Rubach, Martin; Adelmann, Roland; Wittwer, Thorsten; Wahlers, Thorsten

2015-01-01

Objective The effect of mechanical preconditioning on skeletal myoblasts in engineered tissue constructs was investigated to resolve issues associated with conduction block between skeletal myoblast cells and cardiomyocytes. Methods Murine skeletal myoblasts were used to generate engineered tissue constructs with or without application of mechanical strain. After in vitro myotube formation, engineered tissue constructs were co-cultured for 6 days with viable embryonic heart slices. With the use of sharp electrodes, electrical coupling between engineered tissue constructs and embryonic heart slices was assessed in the presence or absence of pharmacologic agents. Results The isolation and expansion procedure for skeletal myoblasts resulted in high yields of homogeneously desmin-positive (97.1% ± 0.1%) cells. Mechanical strain was exerted on myotubes within engineered tissue constructs during gelation of the matrix, generating preconditioned engineered tissue constructs. Electrical coupling between preconditioned engineered tissue constructs and embryonic heart slices was observed; however, no coupling was apparent when engineered tissue constructs were not subjected to mechanical strain. Coupling of cells from engineered tissue constructs to cells in embryonic heart slices showed slower conduction velocities than myocardial cells with the embryonic heart slices (preconditioned engineered tissue constructs vs embryonic heart slices: 0.04 ± 0.02 ms vs 0.10 ± 0.05 ms, P = .011), lower stimulation frequencies (preconditioned engineered tissue constructs vs maximum embryonic heart slices: 4.82 ± 1.42 Hz vs 10.58 ± 1.56 Hz; P = .0009), and higher sensitivities to the gap junction inhibitor (preconditioned engineered tissue constructs vs embryonic heart slices: 0.22 ± 0.07 mmol/L vs 0.93 ± 0.15 mmol/L; P = .0004). Conclusions We have generated skeletal myoblast–based transplantable grafts that electrically couple to myocardium. PMID:22980065

Civil engineering reference guide

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

Merritt, F.S.

1986-01-01

The civil engineering reference guide contains the following: Structural theory. Structural steel design. Concrete design and construction. Wood design and construction. Bridge engineering. Geotechnical engineering. Water engineering. Environmental engineering. Surveying.

22 CFR 228.17 - Special procurement rules for construction and engineering services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... engineering services. 228.17 Section 228.17 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT RULES FOR... construction and engineering services. Advanced developing countries, as defined in § 228.01, which USAID has... engineering services are not eligible to furnish USAID-financed construction and engineering services unless...

22 CFR 228.17 - Special procurement rules for construction and engineering services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... engineering services. 228.17 Section 228.17 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT RULES FOR... construction and engineering services. Advanced developing countries, as defined in § 228.01, which USAID has... engineering services are not eligible to furnish USAID-financed construction and engineering services unless...

22 CFR 228.17 - Special procurement rules for construction and engineering services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... engineering services. 228.17 Section 228.17 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT RULES FOR... construction and engineering services. Advanced developing countries, as defined in § 228.01, which USAID has... engineering services are not eligible to furnish USAID-financed construction and engineering services unless...

25 CFR 700.465 - Technical feasibility.

Code of Federal Regulations, 2010 CFR

2010-04-01

... construction, technology, or another engineering project, however, an application for a construction, technology or another engineering project shall: (a) Include sufficient information to determine the nature... construction, technology, or other engineering project prior to construction. The Commission shall review the...

25 CFR 700.465 - Technical feasibility.

Code of Federal Regulations, 2012 CFR

2012-04-01

... construction, technology, or another engineering project, however, an application for a construction, technology or another engineering project shall: (a) Include sufficient information to determine the nature... construction, technology, or other engineering project prior to construction. The Commission shall review the...

25 CFR 700.465 - Technical feasibility.

Code of Federal Regulations, 2014 CFR

2014-04-01

... construction, technology, or another engineering project, however, an application for a construction, technology or another engineering project shall: (a) Include sufficient information to determine the nature... construction, technology, or other engineering project prior to construction. The Commission shall review the...

25 CFR 700.465 - Technical feasibility.

Code of Federal Regulations, 2011 CFR

2011-04-01

... construction, technology, or another engineering project, however, an application for a construction, technology or another engineering project shall: (a) Include sufficient information to determine the nature... construction, technology, or other engineering project prior to construction. The Commission shall review the...

25 CFR 700.465 - Technical feasibility.

Code of Federal Regulations, 2013 CFR

2013-04-01

... construction, technology, or another engineering project, however, an application for a construction, technology or another engineering project shall: (a) Include sufficient information to determine the nature... construction, technology, or other engineering project prior to construction. The Commission shall review the...

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

Code of Federal Regulations, 2010 CFR

2010-10-01

...-engineer contracts. 31.201-7 Section 31.201-7 Federal Acquisition Regulations System FEDERAL ACQUISITION... 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 these...

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

Code of Federal Regulations, 2012 CFR

2012-10-01

...-engineer contracts. 31.201-7 Section 31.201-7 Federal Acquisition Regulations System FEDERAL ACQUISITION... 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 these...

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

Code of Federal Regulations, 2014 CFR

2014-10-01

...-engineer contracts. 31.201-7 Section 31.201-7 Federal Acquisition Regulations System FEDERAL ACQUISITION... 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 these...

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

Code of Federal Regulations, 2013 CFR

2013-10-01

...-engineer contracts. 31.201-7 Section 31.201-7 Federal Acquisition Regulations System FEDERAL ACQUISITION... 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 these...

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

Code of Federal Regulations, 2011 CFR

2011-10-01

...-engineer contracts. 31.201-7 Section 31.201-7 Federal Acquisition Regulations System FEDERAL ACQUISITION... 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 these...

30 CFR 36.23 - Engine intake system.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Engine intake system. 36.23 Section 36.23... EQUIPMENT Construction and Design Requirements § 36.23 Engine intake system. (a) Construction. The intake... operator's compartment, to shut off the air supply to the engine. This valve shall be constructed to permit...

30 CFR 36.23 - Engine intake system.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Engine intake system. 36.23 Section 36.23... EQUIPMENT Construction and Design Requirements § 36.23 Engine intake system. (a) Construction. The intake... operator's compartment, to shut off the air supply to the engine. This valve shall be constructed to permit...

Transplantation of Tissue-Engineered Cartilage in an Animal Model (Xenograft and Autograft): Construct Validation.

PubMed

Nemoto, Hitoshi; Watson, Deborah; Masuda, Koichi

2015-01-01

Tissue engineering holds great promise for cartilage repair with minimal donor-site morbidity. The in vivo maturation of a tissue-engineered construct can be tested in the subcutaneous tissues of the same species for autografts or of immunocompromised animals for allografts or xenografts. This section describes detailed protocols for the surgical transplantation of a tissue-engineered construct into an animal model to assess construct validity.

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

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 11 2010-01-01 2010-01-01 false Long-range engineering plans and construction work... AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.604 Long-range engineering plans and construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and...

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

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 11 2013-01-01 2013-01-01 false Long-range engineering plans and construction work... AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.604 Long-range engineering plans and construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and...

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

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 11 2014-01-01 2014-01-01 false Long-range engineering plans and construction work... AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.604 Long-range engineering plans and construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and...

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

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 11 2012-01-01 2012-01-01 false Long-range engineering plans and construction work... AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.604 Long-range engineering plans and construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and...

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

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 11 2011-01-01 2011-01-01 false Long-range engineering plans and construction work... AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.604 Long-range engineering plans and construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and...

48 CFR 952.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

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. ...

48 CFR 952.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Construction and architect-engineer contracts. 952.236 Section 952.236 Federal Acquisition Regulations System DEPARTMENT OF ENERGY... Construction and architect-engineer contracts. ...

48 CFR 952.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Construction and architect-engineer contracts. 952.236 Section 952.236 Federal Acquisition Regulations System DEPARTMENT OF ENERGY... Construction and architect-engineer contracts. ...

48 CFR 952.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Construction and architect-engineer contracts. 952.236 Section 952.236 Federal Acquisition Regulations System DEPARTMENT OF ENERGY... Construction and architect-engineer contracts. ...

48 CFR 952.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Construction and architect-engineer contracts. 952.236 Section 952.236 Federal Acquisition Regulations System DEPARTMENT OF ENERGY... Construction and architect-engineer contracts. ...

Evaluation of Hybrid Learning in a Construction Engineering Context: A Mixed-Method Approach

ERIC Educational Resources Information Center

Karabulut-Ilgu, Aliye; Jahren, Charles

2016-01-01

Engineering educators call for a widespread implementation of hybrid learning to respond to rapidly changing demands of the 21st century. In response to this call, a junior-level course in the Construction Engineering program entitled Construction Equipment and Heavy Construction Methods was converted into a hybrid learning model. The overarching…

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

PubMed

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.

78 FR 77334 - Small Business Size Standards: Construction

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-23

... Dredging and Surface Cleanup Activities, an ``exception'' under Other Heavy and Civil Engineering... ``exception'' under Other Heavy and Civil Engineering Construction (NAICS 238910), from $20 million to $30... exception under Other Heavy and Civil Engineering Construction (NAICS 238910) and retain the current size...

Economic Impact Forecast System (EIFS). Version 2.0. Users Manual. Supplement II. European Economic Impact Forecast System (EEIFS), Phase 1, (FRG/EIFS Pilot Model).

DTIC Science & Technology

1982-05-01

Chmpip. tL : Construction engineering Research Laboratory ; available from NTIS. 1982. 71 p. (Technical report / Construction Engineering Researsh ...AD-Al17 661 CONSTRUCTION ENGINEERING RESEARCH LAB (ARMY) CHAMPAIGN IL F/G 5/3 ECONOMIC IMPACT FORECAST SYSTEM (EIFS). VERSION 2.0. USERS MANU--ETC(u...CONSTRUCTION ENGINEERING RESEARCH LABORATORY 4A762720A896-C-004 P.O. BOX 4005, CHAMPAIGN, IL 61820 I. CONTROLLING OFFICE NAME AND ADDRESS It. REPORT

48 CFR 853.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 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 architect-engineer...

48 CFR 853.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 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 architect-engineer...

48 CFR 853.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

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 architect-engineer...

48 CFR 853.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 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 architect-engineer...

48 CFR 853.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 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 architect-engineer...

14 CFR 33.31 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.31 Applicability. This subpart prescribes additional design and construction requirements for reciprocating aircraft engines. ...

14 CFR 33.31 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-01-01

... STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.31 Applicability. This subpart prescribes additional design and construction requirements for reciprocating aircraft engines. ...

14 CFR 33.61 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-01-01

... STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.61 Applicability. This subpart prescribes additional design and construction requirements for turbine aircraft engines. ...

14 CFR 33.61 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-01-01

... STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.61 Applicability. This subpart prescribes additional design and construction requirements for turbine aircraft engines. ...

14 CFR 33.61 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-01-01

... STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.61 Applicability. This subpart prescribes additional design and construction requirements for turbine aircraft engines. ...

Morphological changes in paraurethral area after introduction of tissue engineering construct on the basis of adipose tissue stromal cells.

PubMed

Makarov, A V; Arutyunyan, I V; Bol'shakova, G B; Volkov, A V; Gol'dshtein, D V

2009-10-01

We studied morphological changes in the paraurethral area of Wistar rats after introduction of tissue engineering constructs on the basis of multipotent mesenchymal stem cells and gelatin sponge. The tissue engineering construct containing autologous culture of the stromal fraction of the adipose tissue was most effective. After introduction of this construct we observed more rapid degradation of the construct matrix and more intensive formation of collagen fibers.

Micrometer scale guidance of mesenchymal stem cells to form structurally oriented large-scale tissue engineered cartilage.

PubMed

Chou, Chih-Ling; Rivera, Alexander L; Williams, Valencia; Welter, Jean F; Mansour, Joseph M; Drazba, Judith A; Sakai, Takao; Baskaran, Harihara

2017-09-15

Current clinical methods to treat articular cartilage lesions provide temporary relief of the symptoms but fail to permanently restore the damaged tissue. Tissue engineering, using mesenchymal stem cells (MSCs) combined with scaffolds and bioactive factors, is viewed as a promising method for repairing cartilage injuries. However, current tissue engineered constructs display inferior mechanical properties compared to native articular cartilage, which could be attributed to the lack of structural organization of the extracellular matrix (ECM) of these engineered constructs in comparison to the highly oriented structure of articular cartilage ECM. We previously showed that we can guide MSCs undergoing chondrogenesis to align using microscale guidance channels on the surface of a two-dimensional (2-D) collagen scaffold, which resulted in the deposition of aligned ECM within the channels and enhanced mechanical properties of the constructs. In this study, we developed a technique to roll 2-D collagen scaffolds containing MSCs within guidance channels in order to produce a large-scale, three-dimensional (3-D) tissue engineered cartilage constructs with enhanced mechanical properties compared to current constructs. After rolling the MSC-scaffold constructs into a 3-D cylindrical structure, the constructs were cultured for 21days under chondrogenic culture conditions. The microstructure architecture and mechanical properties of the constructs were evaluated using imaging and compressive testing. Histology and immunohistochemistry of the constructs showed extensive glycosaminoglycan (GAG) and collagen type II deposition. Second harmonic generation imaging and Picrosirius red staining indicated alignment of neo-collagen fibers within the guidance channels of the constructs. Mechanical testing indicated that constructs containing the guidance channels displayed enhanced compressive properties compared to control constructs without these channels. In conclusion, using a novel roll-up method, we have developed large scale MSC based tissue-engineered cartilage that shows microscale structural organization and enhanced compressive properties compared to current tissue engineered constructs. Tissue engineered cartilage constructs made with human mesenchymal stem cells (hMSCs), scaffolds and bioactive factors are a promising solution to treat cartilage defects. A major disadvantage of these constructs is their inferior mechanical properties compared to the native tissue, which is likely due to the lack of structural organization of the extracellular matrix of the engineered constructs. In this study, we developed three-dimensional (3-D) cartilage constructs from rectangular scaffold sheets containing hMSCs in micro-guidance channels and characterized their mechanical properties and metabolic requirements. The work led to a novel roll-up method to embed 2-D microscale structures in 3-D constructs. Further, micro-guidance channels incorporated within the 3-D cartilage constructs led to the production of aligned cell-produced matrix and enhanced mechanical function. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

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

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-23

... Engineering, Architectural Services, Design Policies and Construction Standards AGENCY: Rural Utilities..., engineering services and architectural services for transactions above the established threshold dollar levels... Code of Federal Regulations as follows: PART 1724--ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND...

A puzzle assembly strategy for fabrication of large engineered cartilage tissue constructs.

PubMed

Nover, Adam B; Jones, Brian K; Yu, William T; Donovan, Daniel S; Podolnick, Jeremy D; Cook, James L; Ateshian, Gerard A; Hung, Clark T

2016-03-21

Engineering of large articular cartilage tissue constructs remains a challenge as tissue growth is limited by nutrient diffusion. Here, a novel strategy is investigated, generating large constructs through the assembly of individually cultured, interlocking, smaller puzzle-shaped subunits. These constructs can be engineered consistently with more desirable mechanical and biochemical properties than larger constructs (~4-fold greater Young׳s modulus). A failure testing technique was developed to evaluate the physiologic functionality of constructs, which were cultured as individual subunits for 28 days, then assembled and cultured for an additional 21-35 days. Assembled puzzle constructs withstood large deformations (40-50% compressive strain) prior to failure. Their ability to withstand physiologic loads may be enhanced by increases in subunit strength and assembled culture time. A nude mouse model was utilized to show biocompatibility and fusion of assembled puzzle pieces in vivo. Overall, the technique offers a novel, effective approach to scaling up engineered tissues and may be combined with other techniques and/or applied to the engineering of other tissues. Future studies will aim to optimize this system in an effort to engineer and integrate robust subunits to fill large defects. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Puzzle Assembly Strategy for Fabrication of Large Engineered Cartilage Tissue Constructs

PubMed Central

Nover, Adam B.; Jones, Brian K.; Yu, William T.; Donovan, Daniel S.; Podolnick, Jeremy D.; Cook, James L.; Ateshian, Gerard A.; Hung, Clark T.

2016-01-01

Engineering of large articular cartilage tissue constructs remains a challenge as tissue growth is limited by nutrient diffusion. Here, a novel strategy is investigated, generating large constructs through the assembly of individually cultured, interlocking, smaller puzzle-shaped subunits. These constructs can be engineered consistently with more desirable mechanical and biochemical properties than larger constructs (~4-fold greater Young's modulus). A failure testing technique was developed to evaluate the physiologic functionality of constructs, which were cultured as individual subunits for 28 days, then assembled and cultured for an additional 21-35 days. Assembled puzzle constructs withstood large deformations (40-50% compressive strain) prior to failure. Their ability to withstand physiologic loads may be enhanced by increases in subunit strength and assembled culture time. A nude mouse model was utilized to show biocompatibility and fusion of assembled puzzle pieces in vivo. Overall, the technique offers a novel, effective approach to scaling up engineered tissues and may be combined with other techniques and/or applied to the engineering of other tissues. Future studies will aim to optimize this system in an effort to engineer and integrate robust subunits to fill large defects. PMID:26895780

The 300 H.P. Benz Aircraft Engine

NASA Technical Reports Server (NTRS)

Heller, A

1921-01-01

A description is given of the Benz 12-cylinder aircraft engine. The 300 H.P. engine, with the cylinders placed at an angle of 60 degrees not only realizes a long-cherished conception, but has received refinement in detail. It may be described as a perfect example of modern German aircraft engine construction. Here, a detailed description is given of the construction of this engine. Emphasis is placed on the design and construction of the cylinders, pistons, and connecting rods. Also discussed are engine fitting, lubrication, oil pumps, bearings, the oil tank, fuel pump, carburetors, and cooling system.

Construction and engineering of large biochemical pathways via DNA assembler

PubMed Central

Shao, Zengyi; Zhao, Huimin

2015-01-01

Summary 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. PMID:23996442

An Evaluation of the Pavement Condition Index Prediction Model for Rigid Airfield Pavements

DTIC Science & Technology

1982-09-01

UNCLASSIFIED SECURITY CLASSIFICATION OF THIS PAGO(I*%A Data Entotoi) The United States Army Corps of Engineers, Construction Engineering Research Laboratory...Condition . . . 31 Pavement Design/ Construction ....... . 82 Aircraft Traffic ........ .............. 82 Climate Conditions ........ ............. 84...PATTERSON AFB . . . . . . . . . . . . . . . . . . . . . . . . . 155 C. DATA OBTAINED FROM THE CONSTRUCTION ENGINEERING RESEARCH LABORATORY. .. .. 168 D

48 CFR 1827.304-3 - Contracts for construction work or architect-engineer services. (NASA supplements paragraph (a))

Code of Federal Regulations, 2010 CFR

2010-10-01

... work or architect-engineer services. (NASA supplements paragraph (a)) 1827.304-3 Section 1827.304-3... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Patent Rights Under Government Contracts 1827.304-3 Contracts for construction work or architect-engineer services. (NASA supplements paragraph (a)) (a) For construction or...

48 CFR 936.7101 - Construction contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Construction contracts... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Inspection and Acceptance 936.7101 Construction contracts. (a) Inspection services may be performed by the architect-engineer responsible for the...

48 CFR 936.7101 - Construction contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Construction contracts... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Inspection and Acceptance 936.7101 Construction contracts. (a) Inspection services may be performed by the architect-engineer responsible for the...

48 CFR 936.7101 - Construction contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Construction contracts... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Inspection and Acceptance 936.7101 Construction contracts. (a) Inspection services may be performed by the architect-engineer responsible for the...

48 CFR 936.7101 - Construction contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Construction contracts... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Inspection and Acceptance 936.7101 Construction contracts. (a) Inspection services may be performed by the architect-engineer responsible for the...

48 CFR 936.7101 - Construction contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Construction contracts... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Inspection and Acceptance 936.7101 Construction contracts. (a) Inspection services may be performed by the architect-engineer responsible for the...

Study on evaluation of construction reliability for engineering project based on fuzzy language operator

NASA Astrophysics Data System (ADS)

Shi, Yu-Fang; Ma, Yi-Yi; Song, Ping-Ping

2018-03-01

System Reliability Theory is a research hotspot of management science and system engineering in recent years, and construction reliability is useful for quantitative evaluation of project management level. According to reliability theory and target system of engineering project management, the defination of construction reliability appears. Based on fuzzy mathematics theory and language operator, value space of construction reliability is divided into seven fuzzy subsets and correspondingly, seven membership function and fuzzy evaluation intervals are got with the operation of language operator, which provides the basis of corresponding method and parameter for the evaluation of construction reliability. This method is proved to be scientific and reasonable for construction condition and an useful attempt for theory and method research of engineering project system reliability.

48 CFR 31.105 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

...-engineer contracts. 31.105 Section 31.105 Federal Acquisition Regulations System FEDERAL ACQUISITION... Construction and architect-engineer contracts. (a) This category includes all contracts and contract..., bridges, roads, or other kinds of real property. It also includes architect-engineer contracts related to...

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

Code of Federal Regulations, 2012 CFR

2012-10-01

... 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...-engineer firms. (a) When the contracting officer considers it necessary or advantageous to award a contract...

48 CFR 31.105 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

...-engineer contracts. 31.105 Section 31.105 Federal Acquisition Regulations System FEDERAL ACQUISITION... Construction and architect-engineer contracts. (a) This category includes all contracts and contract..., bridges, roads, or other kinds of real property. It also includes architect-engineer contracts related to...

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

Code of Federal Regulations, 2011 CFR

2011-10-01

... 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...-engineer firms. (a) When the contracting officer considers it necessary or advantageous to award a contract...

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

Code of Federal Regulations, 2010 CFR

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...-engineer firms. (a) When the contracting officer considers it necessary or advantageous to award a contract...

48 CFR 31.105 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

...-engineer contracts. 31.105 Section 31.105 Federal Acquisition Regulations System FEDERAL ACQUISITION... Construction and architect-engineer contracts. (a) This category includes all contracts and contract..., bridges, roads, or other kinds of real property. It also includes architect-engineer contracts related to...

48 CFR 36.702 - Forms for use in contracting for architect-engineer services.

Code of Federal Regulations, 2010 CFR

2010-10-01

... contracting for architect-engineer services. 36.702 Section 36.702 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Standard and Optional Forms for Contracting for Construction, Architect-Engineer Services, and...

48 CFR 36.702 - Forms for use in contracting for architect-engineer services.

Code of Federal Regulations, 2011 CFR

2011-10-01

... contracting for architect-engineer services. 36.702 Section 36.702 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Standard and Optional Forms for Contracting for Construction, Architect-Engineer Services, and...

48 CFR 31.105 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

...-engineer contracts. 31.105 Section 31.105 Federal Acquisition Regulations System FEDERAL ACQUISITION... Construction and architect-engineer contracts. (a) This category includes all contracts and contract..., bridges, roads, or other kinds of real property. It also includes architect-engineer contracts related to...

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

Code of Federal Regulations, 2014 CFR

2014-10-01

... 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...-engineer firms. (a) When the contracting officer considers it necessary or advantageous to award a contract...

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

Code of Federal Regulations, 2013 CFR

2013-10-01

... 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...-engineer firms. (a) When the contracting officer considers it necessary or advantageous to award a contract...

48 CFR 36.702 - Forms for use in contracting for architect-engineer services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... contracting for architect-engineer services. 36.702 Section 36.702 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Standard and Optional Forms for Contracting for Construction, Architect-Engineer Services, and...

Solar power satellite system definition study. Part 2, volume 5: Space operations (construction and transportation)

NASA Technical Reports Server (NTRS)

Miller, K.; Davis, E. E.

1977-01-01

Construction and transportation systems and operations are described for the following combinations: (1) silicon photovoltaic CR=1 satellite constructed primarily in low earth orbit (LEO); (2) silicon photovoltaic CR=1 satellite constructed in geosynchronous earth orbit (GEO); (3) Rankine thermal engine satellite constructed primarily in LEO; and (4) Rankine thermal engine satellite constructed in GEO.

Making Work: Demonstrating Thermodynamic Concepts with Solar-Powered Wax and Rubber Heat Engines

ERIC Educational Resources Information Center

Appleyard, S. J.

2007-01-01

Construction details are provided for simple heat engines that use candle wax and elastomers as working substances. The engines are constructed using common household materials and can be easily constructed in a school classroom or at home. They work reliably and are useful tools for demonstrating the conversion of heat to mechanical work. They…

49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

Code of Federal Regulations, 2014 CFR

2014-10-01

... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

Code of Federal Regulations, 2010 CFR

2010-10-01

... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

Code of Federal Regulations, 2011 CFR

2011-10-01

... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

Code of Federal Regulations, 2012 CFR

2012-10-01

... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

Code of Federal Regulations, 2013 CFR

2013-10-01

... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

Construction Strategy and Progress of Whole Intervertebral Disc Tissue Engineering.

PubMed

Yang, Qiang; Xu, Hai-wei; Hurday, Sookesh; Xu, Bao-shan

2016-02-01

Degenerative disc disease (DDD) is the major cause of low back pain, which usually leads to work absenteeism, medical visits and hospitalization. Because the current conservative procedures and surgical approaches to treatment of DDD only aim to relieve the symptoms of disease but not to regenerate the diseased disc, their long-term efficiency is limited. With the rapid developments in medical science, tissue engineering techniques have progressed markedly in recent years, providing a novel regenerative strategy for managing intervertebral disc disease. However, there are as yet no ideal methods for constructing tissue-engineered intervertebral discs. This paper reviews published reports pertaining to intervertebral disc tissue engineering and summarizes data concerning the seed cells and scaffold materials for tissue-engineered intervertebral discs, construction of tissue-engineered whole intervertebral discs, relevant animal experiments and effects of mechanics on the construction of tissue-engineered intervertebral disc and outlines the existing problems and future directions. Although the perfect regenerative strategy for treating DDD has not yet been developed, great progress has been achieved in the construction of tissue-engineered intervertebral discs. It is believed that ongoing research on intervertebral disc tissue engineering will result in revolutionary progress in the treatment of DDD. © 2016 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

14 CFR 33.61 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.61 Applicability. This subpart prescribes additional design and construction requirements for turbine aircraft engines. ...

14 CFR 33.61 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.61 Applicability. This subpart prescribes additional design and construction requirements for turbine aircraft engines. ...

48 CFR 53.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 2 2011-10-01 2011-10-01 false Construction and architect-engineer contracts. 53.236 Section 53.236 Federal Acquisition Regulations System FEDERAL ACQUISITION...-engineer contracts. ...

48 CFR 53.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Construction and architect-engineer contracts. 53.236 Section 53.236 Federal Acquisition Regulations System FEDERAL ACQUISITION...-engineer contracts. ...

48 CFR 53.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Construction and architect-engineer contracts. 53.236 Section 53.236 Federal Acquisition Regulations System FEDERAL ACQUISITION...-engineer contracts. ...

48 CFR 53.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

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...-engineer contracts. ...

48 CFR 53.236 - Construction and architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 2 2013-10-01 2013-10-01 false Construction and architect-engineer contracts. 53.236 Section 53.236 Federal Acquisition Regulations System FEDERAL ACQUISITION...-engineer contracts. ...

Image-guided tissue engineering

PubMed Central

Ballyns, Jeffrey J; Bonassar, Lawrence J

2009-01-01

Replication of anatomic shape is a significant challenge in developing implants for regenerative medicine. This has lead to significant interest in using medical imaging techniques such as magnetic resonance imaging and computed tomography to design tissue engineered constructs. Implementation of medical imaging and computer aided design in combination with technologies for rapid prototyping of living implants enables the generation of highly reproducible constructs with spatial resolution up to 25 μm. In this paper, we review the medical imaging modalities available and a paradigm for choosing a particular imaging technique. We also present fabrication techniques and methodologies for producing cellular engineered constructs. Finally, we comment on future challenges involved with image guided tissue engineering and efforts to generate engineered constructs ready for implantation. PMID:19583811

22 CFR 228.39 - Special source rules for construction and engineering services.

Code of Federal Regulations, 2010 CFR

2010-04-01

... engineering services. 228.39 Section 228.39 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT RULES ON... engineering services. Advanced developing countries, eligible under Geographic Code 941, which have attained a competitive capability in international markets for construction services or engineering services are not...

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

Code of Federal Regulations, 2013 CFR

2013-01-01

... 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...

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

Code of Federal Regulations, 2012 CFR

2012-01-01

... 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...

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

Code of Federal Regulations, 2011 CFR

2011-01-01

... 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...

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

Code of Federal Regulations, 2014 CFR

2014-01-01

... 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...

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

Code of Federal Regulations, 2010 CFR

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...

22 CFR 228.39 - Special source rules for construction and engineering services.

Code of Federal Regulations, 2011 CFR

2011-04-01

... engineering services. 228.39 Section 228.39 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT RULES ON... engineering services. Advanced developing countries, eligible under Geographic Code 941, which have attained a competitive capability in international markets for construction services or engineering services are not...

Dollar Summary of Federal Supply Classification and Service Category by Company, FY83, Part 5 (N065-W059).

DTIC Science & Technology

1983-01-01

BLDGS 1,269 PHILLIPS SWAGER ASSOCIATES ILLINOIS ARMY A/E CONSTRUCTION /ADMIN 9 SVC BLDGS 174 QUINLIVIAN PIERIK KRAUSE ROBSON JV NEW YORK NAVY A/E...CONSTRUCTION /AIRFIELD & MSL FAC RANCORN WILDMAN & KRAUSE VIRGINIA NAVY A/E CONSTRUCTION /AIRFIELD & MSL FAC REED ALONZO B MASS ARMY A/E CONSTRUCTION...ARCHITECT/ENGINEER - GENERAL CONTRACTOR TOTAL OUADRA ENGINEERING INC ALASKA OCE ARCHITECT/ENGINEER - GENERAL QUINLIVAN PIERIK & KRAUSE MASS ARMY ARCHITECT

Engineer at Lehigh University Campaigns for More Construction Research.

ERIC Educational Resources Information Center

Wheeler, David L.

1987-01-01

A civil engineering professor would like to see civil engineers spend less time looking at broken structures and more time testing construction materials, and has founded a research center for that purpose. (MSE)

Popularizing Geological Education among Civil Engineering Students

ERIC Educational Resources Information Center

Chen, Xiang-jun; Zhou, Ying

2012-01-01

The sustainable development of an economy and a society cannot be realized without the help of modern geoscience. Engineering geology knowledge is necessary on a civil engineering construction site to ensure the construction work goes smoothly. This paper first discusses the importance of geoscience, especially the study of engineering geology.…

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

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-17

... CFR Parts 1724 and 1726 RIN 0572-AC20 Electric Engineering, Architectural Services, Design Policies... standard forms of contracts promulgated by RUS for construction, procurement, engineering services and... XVII of title 7 of the Code of Federal Regulations as follows: PART 1724--ELECTRIC ENGINEERING...

30 CFR 36.25 - Engine exhaust system.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Engine exhaust system. 36.25 Section 36.25... EQUIPMENT Construction and Design Requirements § 36.25 Engine exhaust system. (a) Construction. The exhaust system of the engine shall be designed to withstand an internal pressure equal to 4 times the maximum...

A Knowledge Engineering Approach to Analysis and Evaluation of Construction Schedules

DTIC Science & Technology

1990-02-01

software engineering discipline focusing on constructing KBSs. It is an incremental and cyclical process that requires the interaction of a domain expert(s...the U.S. Army Coips of Engineers ; and (3) the project management software developer, represented by Pinnell Engineering , Inc. Since the primary...the programming skills necessary to convert the raw knowledge intn a form a computer can understand. knowledge engineering : The software engineering

Relative Economy of Different Methods of Airplane Construction

NASA Technical Reports Server (NTRS)

Herrmann, H

1931-01-01

A comparison of the relative economy of airplane construction shows that monoplanes are cheaper than biplanes; that all-metal construction is much more expensive than mixed construction; that multi-engine airplanes are more expensive than single-engine types of the same carrying capacity and speed;that the cost of airplanes is materially reduced by increasing their size without increasing the number of engines. The greatest economy usually coincides with the best aerodynamic and static conditions and the cost is always increased by safety requirements.

Development of a construction engineering manpower system for Georgia DOT.

DOT National Transportation Integrated Search

1994-07-01

The objective of this special research study was to develop a construction engineering manpower management system based primarily on construction dollars and to determine if this type of system will be adequate for the GDOT.

Engineering a lunar photolithoautotroph to thrive on the moon - life or simulacrum?

NASA Astrophysics Data System (ADS)

Ellery, A. A.

2018-07-01

Recent work in developing self-replicating machines has approached the problem as an engineering problem, using engineering materials and methods to implement an engineering analogue of a hitherto uniquely biological function. The question is - can anything be learned that might be relevant to an astrobiological context in which the problem is to determine the general form of biology independent of the Earth. Compared with other non-terrestrial biology disciplines, engineered life is more demanding. Engineering a self-replicating machine tackles real environments unlike artificial life which avoids the problem of physical instantiation altogether by examining software models. Engineering a self-replicating machine is also more demanding than synthetic biology as no library of functional components exists. Everything must be constructed de novo. Biological systems already have the capacity to self-replicate but no engineered machine has yet been constructed with the same ability - this is our primary goal. On the basis of the von Neumann analysis of self-replication, self-replication is a by-product of universal construction capability - a universal constructor is a machine that can construct anything (in a functional sense) given the appropriate instructions (DNA/RNA), energy (ATP) and materials (food). In the biological cell, the universal construction mechanism is the ribosome. The ribosome is a biological assembly line for constructing proteins while DNA constitutes a design specification. For a photoautotroph, the energy source is ambient and the food is inorganic. We submit that engineering a self-replicating machine opens up new areas of astrobiology to be explored in the limits of life.

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

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

Not Available

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 projectsmore » 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.« less

Mountain Plains Learning Experience Guide: Automotive Repair. Course: Engine Repair.

ERIC Educational Resources Information Center

Schramm, C.; Osland, Walt

One of twelve individualized courses included in an automotive repair curriculum, this course covers theory and construction, inspection diagnoses, and service and overhaul of automotive engines. The course is comprised of five units: (1) Fundamentals of Four-Cycle Engines, (2) Engine Construction, (3) Valve Train, (4) Lubricating Systems, and (5)…

7 CFR 1753.15 - General.

Code of Federal Regulations, 2012 CFR

2012-01-01

... funds, postloan architectural or engineering services shall be obtained if (1) the construction cost... TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Engineering Services § 1753.15 General. (a)(1) The standard RUS loan documents contain provisions regarding engineering and architectural services performed...

7 CFR 1753.15 - General.

Code of Federal Regulations, 2011 CFR

2011-01-01

... funds, postloan architectural or engineering services shall be obtained if (1) the construction cost... TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Engineering Services § 1753.15 General. (a)(1) The standard RUS loan documents contain provisions regarding engineering and architectural services performed...

7 CFR 1753.15 - General.

Code of Federal Regulations, 2014 CFR

2014-01-01

... funds, postloan architectural or engineering services shall be obtained if (1) the construction cost... TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Engineering Services § 1753.15 General. (a)(1) The standard RUS loan documents contain provisions regarding engineering and architectural services performed...

7 CFR 1753.15 - General.

Code of Federal Regulations, 2010 CFR

2010-01-01

... funds, postloan architectural or engineering services shall be obtained if (1) the construction cost... TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Engineering Services § 1753.15 General. (a)(1) The standard RUS loan documents contain provisions regarding engineering and architectural services performed...

7 CFR 1753.15 - General.

Code of Federal Regulations, 2013 CFR

2013-01-01

... funds, postloan architectural or engineering services shall be obtained if (1) the construction cost... TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Engineering Services § 1753.15 General. (a)(1) The standard RUS loan documents contain provisions regarding engineering and architectural services performed...

Evaluating the Construct-Coverage of the e-rater[R] Scoring Engine. Research Report. ETS RR-09-01

ERIC Educational Resources Information Center

Quinlan, Thomas; Higgins, Derrick; Wolff, Susanne

2009-01-01

This report evaluates the construct coverage of the e-rater[R[ scoring engine. The matter of construct coverage depends on whether one defines writing skill, in terms of process or product. Originally, the e-rater engine consisted of a large set of components with a proven ability to predict human holistic scores. By organizing these capabilities…

Compendium of Administrators of Land Use and Related Programs. Revision

DTIC Science & Technology

1982-09-01

construction engineering research laboratory Army Nation Unitad Stoic«» Army ^ n * Technical Report N-40 (Revised) September 19 82...CONTRACT OR GRANT NUMBER’«) \\ 9. PERFORMING ORGANIZATION NAME AND ADDRESS U.S. ARMY CONSTRUCTION ENGINEERING RESEARCH LABORATORY...Chief of Engineers (OCE), under Project 4A762720A896, "Environmental Quality for Construction and Operation of Military Facilities" Task 04. "Land Use

Promoting Quality in NAVFAC (Naval Facilities Engineering Command) Construction.

DTIC Science & Technology

1986-01-01

experience. Inspector Checklists To assist their field construction engineers, Owens - Corning Fiberglas Corporation, in conjunction with Texas A&M...that developed by Owens - Corning Fiberglas A I Corporation to assist government inspectors to maintain high - quality standards in their construction...105, No. C03 (September 1979), 187-199. Information in a letter to the author from D.R. Eberts, Quality Assurance Engineer, Owens - Corning Fiberglas

48 CFR 836.602-4 - Selection authority.

Code of Federal Regulations, 2011 CFR

2011-10-01

... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602-4 Selection authority. The Director, Office of Construction and Facilities Management (for Central Office contracts), the Director, Office of Construction Management (for National Cemetery Administration contracts...

48 CFR 836.602-4 - Selection authority.

Code of Federal Regulations, 2012 CFR

2012-10-01

... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602-4 Selection authority. The Director, Office of Construction and Facilities Management (for Central Office contracts), the Director, Office of Construction Management (for National Cemetery Administration contracts...

48 CFR 836.602-4 - Selection authority.

Code of Federal Regulations, 2014 CFR

2014-10-01

... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602-4 Selection authority. The Director, Office of Construction and Facilities Management (for Central Office contracts), the Director, Office of Construction Management (for National Cemetery Administration contracts...

48 CFR 836.602-4 - Selection authority.

Code of Federal Regulations, 2013 CFR

2013-10-01

... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602-4 Selection authority. The Director, Office of Construction and Facilities Management (for Central Office contracts), the Director, Office of Construction Management (for National Cemetery Administration contracts...

25 CFR 900.122 - What does an Indian tribe or tribal organization do if it wants to secure a construction contract?

Code of Federal Regulations, 2010 CFR

2010-04-01

... UNDER THE INDIAN SELF-DETERMINATION AND EDUCATION ASSISTANCE ACT Construction § 900.122 What does an... information available about the construction project, including construction drawings, maps, engineering... tribal organization to review all plans, specifications, engineering reports, cost estimates, and other...

A Cost-Minimization Analysis of Tissue-Engineered Constructs for Corneal Endothelial Transplantation

PubMed Central

Tan, Tien-En; Peh, Gary S. L.; George, Benjamin L.; Cajucom-Uy, Howard Y.; Dong, Di; Finkelstein, Eric A.; Mehta, Jodhbir S.

2014-01-01

Corneal endothelial transplantation or endothelial keratoplasty has become the preferred choice of transplantation for patients with corneal blindness due to endothelial dysfunction. Currently, there is a worldwide shortage of transplantable tissue, and demand is expected to increase further with aging populations. Tissue-engineered alternatives are being developed, and are likely to be available soon. However, the cost of these constructs may impair their widespread use. A cost-minimization analysis comparing tissue-engineered constructs to donor tissue procured from eye banks for endothelial keratoplasty was performed. Both initial investment costs and recurring costs were considered in the analysis to arrive at a final tissue cost per transplant. The clinical outcomes of endothelial keratoplasty with tissue-engineered constructs and with donor tissue procured from eye banks were assumed to be equivalent. One-way and probabilistic sensitivity analyses were performed to simulate various possible scenarios, and to determine the robustness of the results. A tissue engineering strategy was cheaper in both investment cost and recurring cost. Tissue-engineered constructs for endothelial keratoplasty could be produced at a cost of US$880 per transplant. In contrast, utilizing donor tissue procured from eye banks for endothelial keratoplasty required US$3,710 per transplant. Sensitivity analyses performed further support the results of this cost-minimization analysis across a wide range of possible scenarios. The use of tissue-engineered constructs for endothelial keratoplasty could potentially increase the supply of transplantable tissue and bring the costs of corneal endothelial transplantation down, making this intervention accessible to a larger group of patients. Tissue-engineering strategies for corneal epithelial constructs or other tissue types, such as pancreatic islet cells, should also be subject to similar pharmacoeconomic analyses. PMID:24949869

A cost-minimization analysis of tissue-engineered constructs for corneal endothelial transplantation.

PubMed

Tan, Tien-En; Peh, Gary S L; George, Benjamin L; Cajucom-Uy, Howard Y; Dong, Di; Finkelstein, Eric A; Mehta, Jodhbir S

2014-01-01

Corneal endothelial transplantation or endothelial keratoplasty has become the preferred choice of transplantation for patients with corneal blindness due to endothelial dysfunction. Currently, there is a worldwide shortage of transplantable tissue, and demand is expected to increase further with aging populations. Tissue-engineered alternatives are being developed, and are likely to be available soon. However, the cost of these constructs may impair their widespread use. A cost-minimization analysis comparing tissue-engineered constructs to donor tissue procured from eye banks for endothelial keratoplasty was performed. Both initial investment costs and recurring costs were considered in the analysis to arrive at a final tissue cost per transplant. The clinical outcomes of endothelial keratoplasty with tissue-engineered constructs and with donor tissue procured from eye banks were assumed to be equivalent. One-way and probabilistic sensitivity analyses were performed to simulate various possible scenarios, and to determine the robustness of the results. A tissue engineering strategy was cheaper in both investment cost and recurring cost. Tissue-engineered constructs for endothelial keratoplasty could be produced at a cost of US$880 per transplant. In contrast, utilizing donor tissue procured from eye banks for endothelial keratoplasty required US$3,710 per transplant. Sensitivity analyses performed further support the results of this cost-minimization analysis across a wide range of possible scenarios. The use of tissue-engineered constructs for endothelial keratoplasty could potentially increase the supply of transplantable tissue and bring the costs of corneal endothelial transplantation down, making this intervention accessible to a larger group of patients. Tissue-engineering strategies for corneal epithelial constructs or other tissue types, such as pancreatic islet cells, should also be subject to similar pharmacoeconomic analyses.

23 CFR 661.3 - Who must comply with this regulation?

Code of Federal Regulations, 2013 CFR

2013-04-01

... authorities must comply to participate in the IRRBP by applying for preliminary engineering (PE), construction, and construction engineering (CE) activities for the replacement or rehabilitation of structurally....3 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC...

23 CFR 661.3 - Who must comply with this regulation?

Code of Federal Regulations, 2010 CFR

2010-04-01

... authorities must comply to participate in the IRRBP by applying for preliminary engineering (PE), construction, and construction engineering (CE) activities for the replacement or rehabilitation of structurally....3 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC...

23 CFR 661.3 - Who must comply with this regulation?

Code of Federal Regulations, 2012 CFR

2012-04-01

... authorities must comply to participate in the IRRBP by applying for preliminary engineering (PE), construction, and construction engineering (CE) activities for the replacement or rehabilitation of structurally....3 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC...

23 CFR 661.3 - Who must comply with this regulation?

Code of Federal Regulations, 2011 CFR

2011-04-01

... authorities must comply to participate in the IRRBP by applying for preliminary engineering (PE), construction, and construction engineering (CE) activities for the replacement or rehabilitation of structurally....3 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC...

23 CFR 661.3 - Who must comply with this regulation?

Code of Federal Regulations, 2014 CFR

2014-04-01

... authorities must comply to participate in the IRRBP by applying for preliminary engineering (PE), construction, and construction engineering (CE) activities for the replacement or rehabilitation of structurally....3 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC...

KSC-2012-6405

NASA Image and Video Library

2012-09-20

CAPE CANAVERAL, Fla. -- At NASA’s Kennedy Space Center in Florida, a groundbreaking was held to mark the start of construction on the Antenna Test Bed Array for the Ka-Band Objects Observation and Monitoring, or Ka-BOOM system. Using ceremonial shovels to mark the site, from left are Michael Le, lead design engineer and construction manager Sue Vingris, Cape Design Engineer Co. project manager Kannan Rengarajan, chief executive officer of Cape Design Engineer Co. Lutfi Mized, president of Cape Design Engineer Co. David Roelandt, construction site superintendent with Cape Design Engineer Co. Marc Seibert, NASA project manager Michael Miller, NASA project manager Peter Aragona, KSC’s Electromagnetic Lab manager Stacy Hopper, KSCs master planning supervisor Dr. Bary Geldzabler, NASA chief scientist and KSC’s Chief Technologist Karen Thompson. The construction site is near the former Vertical Processing Facility, which has been demolished. Workers will begin construction on the pile foundations for the 40-foot-diameter dish antenna arrays and their associated utilities, and prepare the site for the operations command center facility. Photo credit: NASA/Charisse Nahser

KSC-2012-6404

NASA Image and Video Library

2012-09-20

CAPE CANAVERAL, Fla. -- At NASA’s Kennedy Space Center in Florida, a groundbreaking was held to mark the start of construction on the Antenna Test Bed Array for the Ka-Band Objects Observation and Monitoring, or Ka-BOOM system. Holding ceremonial shovels, from left are Michael Le, lead design engineer and construction manager Sue Vingris, Cape Design Engineer Co. project manager Kannan Rengarajan, chief executive officer of Cape Design Engineer Co. Lutfi Mized, president of Cape Design Engineer Co. David Roelandt, construction site superintendent with Cape Design Engineer Co. Marc Seibert, NASA project manager Michael Miller, NASA project manager Peter Aragona, KSC’s Electromagnetic Lab manager Stacy Hopper, KSCs master planning supervisor Dr. Bary Geldzabler, NASA chief scientist and KSC’s Chief Technologist Karen Thompson. The construction site is near the former Vertical Processing Facility, which has been demolished. Workers will begin construction on the pile foundations for the 40-foot-diameter dish antenna arrays and their associated utilities, and prepare the site for the operations command center facility. Photo credit: NASA/Charisse Nahser

RESEARCH AND DESIGN ABOUT VERSATILE 3D-CAD ENGINE FOR CONSTRUCTION

NASA Astrophysics Data System (ADS)

Tanaka, Shigenori; Kubota, Satoshi; Kitagawa, Etsuji; Monobe, Kantaro; Nakamura, Kenji

In the construction field of Japan, it is an important subject to build the environment where 3D-CAD data is used for CALS/EC, information construction, and an improvement in productivity. However, in the construction field, 3D-CAD software does not exist under the present circumstances. Then, in order to support development of domestic 3D-CAD software, it is required to develop a 3D-CAD engine. In this research, in order to familiarize the 3D-CAD software at low cost and quickly and build the environment where the 3D-CAD software is utilizable, investigation for designing a 3D-CAD engine is proposed. The target for investigation are the use scene of 3D-CAD, the seeds which accompany 3D-CAD, a standardization trend, existing products, IT component engineering. Based on results of the investigation, the functional requirements for the 3D-CAD engine for the construction field were concluded.

Multimedia techniques for construction education and training : final report.

DOT National Transportation Integrated Search

2017-02-01

The current profession of civil engineering often focuses education and training on code compliance rather than constructability and construction techniques. Also, it is well accepted that it takes a decade or more for engineers to develop a high-lev...

Metabolic engineering of Escherichia coli for the production of phenylpyruvate derivatives.

PubMed

Liu, Shuang Ping; Zhang, Liang; Mao, Jian; Ding, Zhong Yang; Shi, Gui Yang

2015-11-01

Phenylpyruvate derivatives (PPD), such as phenylpropanoids, DL-phenylglycine, dl-phenylalanine, and styrene, are biosynthesized using phenylpyruvate as the precursor. They are widely used in human health and nutrition products. Recently, metabolic engineering provides effective strategies to develop PPD producers. Based on phenylpyruvate-producing chassis, genetically defined PPD producers have been successfully constructed. In this work, the most recent information on genetics and on the molecular mechanisms regulating phenylpyruvate synthesis pathways in Escherichia coli are summarized, and the engineering strategies to construct the PPD producers are also discussed. The enzymes and pathways are proposed for PPD-producer constructions, and potential difficulties in strain construction are also identified and discussed. With respect to recent advances in synthetic biology, future strategies to construct efficiently producers are discussed. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Engineering cartilage or endochondral bone: a comparison of different naturally derived hydrogels.

PubMed

Sheehy, Eamon J; Mesallati, Tariq; Vinardell, Tatiana; Kelly, Daniel J

2015-02-01

Cartilaginous tissues engineered using mesenchymal stem cells (MSCs) have been shown to generate bone in vivo by executing an endochondral programme. This may hinder the use of MSCs for articular cartilage regeneration, but opens the possibility of using engineered cartilaginous tissues for large bone defect repair. Hydrogels may be an attractive tool in the scaling-up of such tissue engineered grafts for endochondral bone regeneration. In this study, we compared the capacity of different naturally derived hydrogels (alginate, chitosan and fibrin) to support chondrogenesis and hypertrophy of MSCs in vitro and endochondral ossification in vivo. In vitro, alginate and chitosan constructs accumulated the highest levels of sulfated glycosaminoglycan (sGAG), with chitosan constructs synthesizing the highest levels of collagen. Alginate and fibrin constructs supported the greatest degree of calcium accumulation, though only fibrin constructs calcified homogeneously. In vivo, chitosan constructs facilitated neither vascularization nor endochondral ossification, and also retained the greatest amount of sGAG, suggesting it to be a more suitable material for the engineering of articular cartilage. Both alginate and fibrin constructs facilitated vascularization and endochondral bone formation as well as the development of a bone marrow environment. Alginate constructs accumulated significantly more mineral and supported greater bone formation in central regions of the engineered tissue. In conclusion, this study demonstrates the capacity of chitosan hydrogels to promote and better maintain a chondrogenic phenotype in MSCs and highlights the potential of utilizing alginate hydrogels for MSC-based endochondral bone tissue engineering applications. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Nuclear Engineering Technologists in the Nuclear Power Era

ERIC Educational Resources Information Center

Wang, C. H.; And Others

1974-01-01

Describes manpower needs in nuclear engineering in the areas of research and development, architectural engineering and construction supervision, power reactor operations, and regulatory tasks. Outlines a suitable curriculum to prepare students for the tasks related to construction and operation of power reactors. (GS)

Engineered phages for electronics.

PubMed

Cui, Yue

2016-11-15

Phages are traditionally widely studied in biology and chemistry. In recent years, engineered phages have attracted significant attentions for functionalization or construction of electronic devices, due to their specific binding, catalytic, nucleating or electronic properties. To apply the engineered phages in electronics, these are a number of interesting questions: how to engineer phages for electronics? How are the engineered phages characterized? How to assemble materials with engineered phages? How are the engineered phages micro or nanopatterned? What are the strategies to construct electronics devices with engineered phages? This review will highlight the early attempts to address these questions and explore the fundamental and practical aspects of engineered phages in electronics, including the approaches for selection or expression of specific peptides on phage coat proteins, characterization of engineered phages in electronics, assembly of electronic materials, patterning of engineered phages, and construction of electronic devices. It provides the methodologies and opens up ex-cit-ing op-por-tu-ni-ties for the development of a variety of new electronic materials and devices based on engineered phages for future applications. Copyright © 2016 Elsevier B.V. All rights reserved.

48 CFR 936.202-70 - Specifications charges.

Code of Federal Regulations, 2011 CFR

2011-10-01

... payments, the invitations for bids should so state, and the architect-engineer or construction management... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 936.202-70 Specifications charges. (a) To support all invitations for bids, plans and...

48 CFR 936.202-70 - Specifications charges.

Code of Federal Regulations, 2012 CFR

2012-10-01

... payments, the invitations for bids should so state, and the architect-engineer or construction management... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 936.202-70 Specifications charges. (a) To support all invitations for bids, plans and...

48 CFR 936.202-70 - Specifications charges.

Code of Federal Regulations, 2013 CFR

2013-10-01

... payments, the invitations for bids should so state, and the architect-engineer or construction management... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 936.202-70 Specifications charges. (a) To support all invitations for bids, plans and...

48 CFR 936.202-70 - Specifications charges.

Code of Federal Regulations, 2014 CFR

2014-10-01

... payments, the invitations for bids should so state, and the architect-engineer or construction management... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 936.202-70 Specifications charges. (a) To support all invitations for bids, plans and...

7 CFR 1726.404 - Non-site specific construction contract closeout.

Code of Federal Regulations, 2014 CFR

2014-01-01

... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Contract... equipment is supplied under a construction contract, the borrower (acting through its engineer, if... equipment. The borrower (acting through its engineer, if applicable) will schedule such inspection and...

7 CFR 1726.404 - Non-site specific construction contract closeout.

Code of Federal Regulations, 2010 CFR

2010-01-01

... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Contract... equipment is supplied under a construction contract, the borrower (acting through its engineer, if... equipment. The borrower (acting through its engineer, if applicable) will schedule such inspection and...

7 CFR 1726.404 - Non-site specific construction contract closeout.

Code of Federal Regulations, 2011 CFR

2011-01-01

... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Contract... equipment is supplied under a construction contract, the borrower (acting through its engineer, if... equipment. The borrower (acting through its engineer, if applicable) will schedule such inspection and...

7 CFR 1726.404 - Non-site specific construction contract closeout.

Code of Federal Regulations, 2012 CFR

2012-01-01

... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Contract... equipment is supplied under a construction contract, the borrower (acting through its engineer, if... equipment. The borrower (acting through its engineer, if applicable) will schedule such inspection and...

7 CFR 1726.404 - Non-site specific construction contract closeout.

Code of Federal Regulations, 2013 CFR

2013-01-01

... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Contract... equipment is supplied under a construction contract, the borrower (acting through its engineer, if... equipment. The borrower (acting through its engineer, if applicable) will schedule such inspection and...

48 CFR 936.202-70 - Specifications charges.

Code of Federal Regulations, 2010 CFR

2010-10-01

... payments, the invitations for bids should so state, and the architect-engineer or construction management... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 936.202-70 Specifications charges. (a) To support all invitations for bids, plans and...

Safety in Construction Using Virtual Reality (SAVR): A Model for Labor Safety. Working Paper Series WP-022.

ERIC Educational Resources Information Center

Hadipriono, Fabian C.; And Others

An interactive training model called SAVR (Safety in Construction Using Virtual Reality) was developed to train construction students, novice engineers, and construction workers to prevent falls from scaffolding. The model was implemented in a graphics supercomputer, the ONYX Reality Engine2. The SAVR model provides trainees with an immersive,…

14 CFR 33.11 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.11 Applicability. This subpart prescribes the general design and construction requirements for reciprocating and turbine aircraft engines. ...

14 CFR 33.11 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-01-01

... STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.11 Applicability. This subpart prescribes the general design and construction requirements for reciprocating and turbine aircraft engines. ...

SAE 2018-01-1412 Constructing Engine Maps - Presentation at the April 2018 World Congress

EPA Pesticide Factsheets

This presentation describes important factors and approach, along with the process for constructing complete engine maps using engine dynamometer and in-vehicle test data for use in ALPHA or any other full vehicle simulation which performs similar analyses

Cartilage constructs engineered from chondrocytes overexpressing IGF-I improve the repair of osteochondral defects in a rabbit model.

PubMed

Madry, H; Kaul, G; Zurakowski, D; Vunjak-Novakovic, G; Cucchiarini, M

2013-04-16

Tissue engineering combined with gene therapy is a promising approach for promoting articular cartilage repair. Here, we tested the hypothesis that engineered cartilage with chondrocytes overexpressing a human insulin-like growth factor I (IGF-I) gene can enhance the repair of osteochondral defects, in a manner dependent on the duration of cultivation. Genetically modified chondrocytes were cultured on biodegradable polyglycolic acid scaffolds in dynamic flow rotating bioreactors for either 10 or 28 d. The resulting cartilaginous constructs were implanted into osteochondral defects in rabbit knee joints. After 28 weeks of in vivo implantation, immunoreactivity to ß-gal was detectable in the repair tissue of defects that received lacZ constructs. Engineered cartilaginous constructs based on IGF-I-overexpressing chondrocytes markedly improved osteochondral repair compared with control (lacZ) constructs. Moreover, IGF-I constructs cultivated for 28 d in vitro significantly promoted osteochondral repair vis-à-vis similar constructs cultivated for 10 d, leading to significantly decreased osteoarthritic changes in the cartilage adjacent to the defects. Hence, the combination of spatially defined overexpression of human IGF-I within a tissue-engineered construct and prolonged bioreactor cultivation resulted in most enhanced articular cartilage repair and reduction of osteoarthritic changes in the cartilage adjacent to the defect. Such genetically enhanced tissue engineering provides a versatile tool to evaluate potential therapeutic genes in vivo and to improve our comprehension of the development of the repair tissue within articular cartilage defects. Insights gained with additional exploration using this model may lead to more effective treatment options for acute cartilage defects.

CARTILAGE CONSTRUCTS ENGINEERED FROM CHONDROCYTES OVEREXPRESSING IGF-I IMPROVE THE REPAIR OF OSTEOCHONDRAL DEFECTS IN A RABBIT MODEL

PubMed Central

Madry, Henning; Kaul, Gunter; Zurakowski, David; Vunjak-Novakovic, Gordana; Cucchiarini, Magali

2015-01-01

Tissue engineering combined with gene therapy is a promising approach for promoting articular cartilage repair. Here, we tested the hypothesis that engineered cartilage with chondrocytes over expressing a human insulin-like growth factor I (IGF-I) gene can enhance the repair of osteochondral defects, in a manner dependent on the duration of cultivation. Genetically modified chondrocytes were cultured on biodegradable polyglycolic acid scaffolds in dynamic flow rotating bioreactors for either 10 or 28 d. The resulting cartilaginous constructs were implanted into osteochondral defects in rabbit knee joints. After 28 weeks of in vivo implantation, immunoreactivity to ß-gal was detectable in the repair tissue of defects that received lacZ constructs. Engineered cartilaginous constructs based on IGF-I-over expressing chondrocytes markedly improved osteochondral repair compared with control (lacZ) constructs. Moreover, IGF-I constructs cultivated for 28 d in vitro significantly promoted osteochondral repair vis-à-vis similar constructs cultivated for 10 d, leading to significantly decreased osteoarthritic changes in the cartilage adjacent to the defects. Hence, the combination of spatially defined overexpression of human IGF-I within a tissue-engineered construct and prolonged bioreactor cultivation resulted in most enhanced articular cartilage repair and reduction of osteoarthritic changes in the cartilage adjacent to the defect. Such genetically enhanced tissue engineering provides a versatile tool to evaluate potential therapeutic genes in vivo and to improve our comprehension of the development of the repair tissue within articular cartilage defects. Insights gained with additional exploration using this model may lead to more effective treatment options for acute cartilage defects. PMID:23588785

48 CFR 52.248-3 - Value Engineering-Construction.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 2 2013-10-01 2013-10-01 false Value Engineering....248-3 Value Engineering—Construction. As prescribed in 48.202, insert the following clause: Value Engineering—Construction (OCT 2010) (a) General. The Contractor is encouraged to develop, prepare, and submit...

48 CFR 52.248-3 - Value Engineering-Construction.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Value Engineering....248-3 Value Engineering—Construction. As prescribed in 48.202, insert the following clause: Value Engineering—Construction (OCT 2010) (a) General. The Contractor is encouraged to develop, prepare, and submit...

48 CFR 52.248-3 - Value Engineering-Construction.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Value Engineering....248-3 Value Engineering—Construction. As prescribed in 48.202, insert the following clause: Value Engineering—Construction (OCT 2010) (a) General. The Contractor is encouraged to develop, prepare, and submit...

48 CFR 52.248-3 - Value Engineering-Construction.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 2 2011-10-01 2011-10-01 false Value Engineering....248-3 Value Engineering—Construction. As prescribed in 48.202, insert the following clause: Value Engineering—Construction (OCT 2010) (a) General. The Contractor is encouraged to develop, prepare, and submit...

48 CFR 52.248-3 - Value Engineering-Construction.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Value Engineering....248-3 Value Engineering—Construction. As prescribed in 48.202, insert the following clause: Value Engineering—Construction (OCT 2010) (a) General. The Contractor is encouraged to develop, prepare, and submit...

Monitoring sinew contraction during formation of tissue-engineered fibrin-based ligament constructs.

PubMed

Paxton, Jennifer Z; Wudebwe, Uchena N G; Wang, Anqi; Woods, Daniel; Grover, Liam M

2012-08-01

The ability to study the gross morphological changes occurring during tissue formation is vital to producing tissue-engineered structures of clinically relevant dimensions in vitro. Here, we have used nondestructive methods of digital imaging and optical coherence tomography to monitor the early-stage formation and subsequent maturation of fibrin-based tissue-engineered ligament constructs. In addition, the effect of supplementation with essential promoters of collagen synthesis, ascorbic acid (AA) and proline (P), has been assessed. Contraction of the cell-seeded fibrin gel occurs unevenly within the first 5 days of culture around two fixed anchor points before forming a longitudinal ligament-like construct. AA+P supplementation accelerates gel contraction in the maturation phase of development, producing ligament-like constructs with a higher collagen content and distinct morphology to that of unsupplemented constructs. These studies highlight the importance of being able to control the methods of tissue formation and maturation in vitro to enable the production of tissue-engineered constructs with suitable replacement tissue characteristics for repair of clinical soft-tissue injuries.

3D Printed Vascular Networks Enhance Viability in High-Volume Perfusion Bioreactor.

PubMed

Ball, Owen; Nguyen, Bao-Ngoc B; Placone, Jesse K; Fisher, John P

2016-12-01

There is a significant clinical need for engineered bone graft substitutes that can quickly, effectively, and safely repair large segmental bone defects. One emerging field of interest involves the growth of engineered bone tissue in vitro within bioreactors, the most promising of which are perfusion bioreactors. Using bioreactor systems, tissue engineered bone constructs can be fabricated in vitro. However, these engineered constructs lack inherent vasculature and once implanted, quickly develop a necrotic core, where no nutrient exchange occurs. Here, we utilized COMSOL modeling to predict oxygen diffusion gradients throughout aggregated alginate constructs, which allowed for the computer-aided design of printable vascular networks, compatible with any large tissue engineered construct cultured in a perfusion bioreactor. We investigated the effect of 3D printed macroscale vascular networks with various porosities on the viability of human mesenchymal stem cells in vitro, using both gas-permeable, and non-gas permeable bioreactor growth chamber walls. Through the use of 3D printed vascular structures in conjunction with a tubular perfusion system bioreactor, cell viability was found to increase by as much as 50% in the core of these constructs, with in silico modeling predicting construct viability at steady state.

3D Printed Vascular Networks Enhance Viability in High-Volume Perfusion Bioreactor

PubMed Central

Ball, Owen; Nguyen, Bao-Ngoc B.; Placone, Jesse K.; Fisher, John P.

2016-01-01

There is a significant clinical need for engineered bone graft substitutes that can quickly, effectively, and safely repair large segmental bone defects. One emerging field of interest involves the growth of engineered bone tissue in vitro within bioreactors, the most promising of which are perfusion bioreactors. Using bioreactor systems, tissue engineered bone constructs can be fabricated in vitro. However, these engineered constructs lack inherent vasculature and once implanted, quickly develop a necrotic core, where no nutrient exchange occurs. Here, we utilized COMSOL modeling to predict oxygen diffusion gradients throughout aggregated alginate constructs, which allowed for the computer-aided design of printable vascular networks, compatible with any large tissue engineered construct cultured in a perfusion bioreactor. We investigated the effect of 3D printed macroscale vascular networks with various porosities on the viability of human mesenchymal stem cells in vitro, using both gas-permeable, and non-gas permeable bioreactor growth chamber walls. Through the use of 3D printed vascular structures in conjunction with a tubular perfusion system bioreactor, cell viability was found to increase by as much as 50% in the core of these constructs, with in silico modeling predicting construct viability at steady state. PMID:27272210

Microvascular Guidance: A Challenge to Support the Development of Vascularised Tissue Engineering Construct

PubMed Central

Sukmana, Irza

2012-01-01

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. PMID:22623881

Space construction activities

NASA Technical Reports Server (NTRS)

1991-01-01

The Center for Space Construction at the University of Colorado at Boulder was established in 1988 as a University Space Engineering Research Center. The mission of the Center is to conduct interdisciplinary engineering research which is critical to the construction of future space structures and systems and to educate students who will have the vision and technical skills to successfully lead future space construction activities. The research activities are currently organized around two central projects: Orbital Construction and Lunar Construction. Summaries of the research projects are included.

Opportunities for Multidisciplinary Research in Partnership with Rock Engineers at the Deep Underground Science and Engineering Laboratory

NASA Astrophysics Data System (ADS)

Laughton, C.

2008-12-01

For the last half century the physics community has increasingly turned to the use of underground space to conduct basic research. The community is currently planning to conduct a new generation of underground experiments at the Deep Underground Science and Engineering Laboratory (DUSEL). DUSEL will be constructed within the footprint of the defunct Homestake Gold Mine, located in Lead, South Dakota. Physics proposals call for the construction of new caverns in which to conduct major new experiments. Some of the proposed laboratory facilities will be significantly larger and deeper than any previously constructed. The talk will highlight possible opportunities for integrating multi-disciplinary research in to the cavern construction program, and will stress the need to work closely with design and construction contractors to ensure that research goals can be achieve with minimal impact on project work. The constructors of large caverns should be particularly receptive to, and encouraging of geoscience research that could improve the engineering characterization of the rock mass. An improved understanding of the rock mass, as the host construction material, would result in a more reliable cavern design and construction process, and a reduced construction risk to the Project.

The trajectories of Prevention through Design in construction.

PubMed

Toole, T Michael; Gambatese, John

2008-01-01

Construction Hazards Prevention through Design (CHPtD) is a process in which engineers and architects explicitly consider the safety of construction workers during the design process. Although articles on CHPtD have appeared in top construction journals, the literature has not addressed technical principles underlying CHPtD to help designers better perform CHPtD, to facilitate the development of additional CHPtD tools, and to predict the future path of CHPtD. This theoretical paper uses the existing literature on CHPtD and current action research associated with several CHPtD workgroups to analyze how CHPtD will likely evolve over the coming decades. There are four trajectories along which CHPtD will progress. (a) Designs will increasingly facilitate prefabricated construction; (b) designers will increasingly choose materials and systems that are inherently safer than alternatives; (c) designers will increasingly perform construction engineering; and (d) designers will increasingly apply spatial considerations to reduce worker hazards. By understanding how CHPtD may be manifested in the engineering-procurement-construction (EPC) industry, practitioners can better prepare for adopting CHPtD within their organizations and construction and engineering educators can better prepare their graduates to perform CHPtD.

7 CFR 1724.32 - Inspection and certification of work order construction.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND... construction. The provisions of this section apply to all borrower electric system facilities regardless of the... performed within 6 months of the completion of construction, and are performed by a licensed engineer...

7 CFR 1724.32 - Inspection and certification of work order construction.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND... construction. The provisions of this section apply to all borrower electric system facilities regardless of the... performed within 6 months of the completion of construction, and are performed by a licensed engineer...

Final Environmental Assessment: Addressing Construction of a New Civil Engineering Workshop at Bellows Air Force Station, O’ahu, Hawaii

DTIC Science & Technology

2010-03-01

FINAL ENVIRONMENTAL ASSESSMENT ADDRESSING CONSTRUCTION OF A NEW CIVIL ENGINEERING WORKSHOP AT BELLOWS AIR FORCE STATION , O‘AHU, HAWAI‘I...Minimize impacts on other Bellows AFS functions and environmental resources This alternative would be located in an area located near Building 546 and...Preparation of An Environmental Assessment for the Proposed Construction of New Civil Engineering Workshop at Bellows Air !Force Station Thank you

Review on antibacterial characteristics of bridge engineering biomaterials.

PubMed

Zhao, Qing-Qing; Chen, Meng-Yao; He, Rui-Lin; Zhang, Zhong-Feng; Ashraf, Muhammad Aqeel

2016-01-01

This review summarizes the research on timber construction materials used in bridge construction. It focuses on the application of antiseptic treatments and the use of timber engineering materials in decks and bridges. This review also provides an overview on the future research and prospects of engineered timber materials.

30 CFR 36.23 - Engine intake system.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Engine intake system. 36.23 Section 36.23... EQUIPMENT Construction and Design Requirements § 36.23 Engine intake system. (a) Construction. The intake... intake system without permanent deformation and shall prevent the propagation of flame through the joint...

Space Transportation System Western Launch Site Construction Management Information System - A Case Study.

DTIC Science & Technology

1979-09-01

The Corps of Engineers Management Information System (COEMIS) is used by the Corps of Engineers in their role as Construction Agents on Air Force...California. The research concluded that the Corps of Engineers Management Information System can be an effective, efficient management tool which has the

A modular approach to creating large engineered cartilage surfaces.

PubMed

Ford, Audrey C; Chui, Wan Fung; Zeng, Anne Y; Nandy, Aditya; Liebenberg, Ellen; Carraro, Carlo; Kazakia, Galateia; Alliston, Tamara; O'Connell, Grace D

2018-01-23

Native articular cartilage has limited capacity to repair itself from focal defects or osteoarthritis. Tissue engineering has provided a promising biological treatment strategy that is currently being evaluated in clinical trials. However, current approaches in translating these techniques to developing large engineered tissues remains a significant challenge. In this study, we present a method for developing large-scale engineered cartilage surfaces through modular fabrication. Modular Engineered Tissue Surfaces (METS) uses the well-known, but largely under-utilized self-adhesion properties of de novo tissue to create large scaffolds with nutrient channels. Compressive mechanical properties were evaluated throughout METS specimens, and the tensile mechanical strength of the bonds between attached constructs was evaluated over time. Raman spectroscopy, biochemical assays, and histology were performed to investigate matrix distribution. Results showed that by Day 14, stable connections had formed between the constructs in the METS samples. By Day 21, bonds were robust enough to form a rigid sheet and continued to increase in size and strength over time. Compressive mechanical properties and glycosaminoglycan (GAG) content of METS and individual constructs increased significantly over time. The METS technique builds on established tissue engineering accomplishments of developing constructs with GAG composition and compressive properties approaching native cartilage. This study demonstrated that modular fabrication is a viable technique for creating large-scale engineered cartilage, which can be broadly applied to many tissue engineering applications and construct geometries. Copyright © 2017 Elsevier Ltd. All rights reserved.

Building information modelling review with potential applications in tunnel engineering of China.

PubMed

Zhou, Weihong; Qin, Haiyang; Qiu, Junling; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin

2017-08-01

Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance.

Building information modelling review with potential applications in tunnel engineering of China

PubMed Central

Zhou, Weihong; Qin, Haiyang; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin

2017-01-01

Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance. PMID:28878970

Building information modelling review with potential applications in tunnel engineering of China

NASA Astrophysics Data System (ADS)

Zhou, Weihong; Qin, Haiyang; Qiu, Junling; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin

2017-08-01

Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance.

Constructs and methods for genome editing and genetic engineering of fungi and protists

DOEpatents

Hittinger, Christopher Todd; Alexander, William Gerald

2018-01-30

Provided herein are constructs for genome editing or genetic engineering in fungi or protists, methods of using the constructs and media for use in selecting cells. The construct include a polynucleotide encoding a thymidine kinase operably connected to a promoter, suitably a constitutive promoter; a polynucleotide encoding an endonuclease operably connected to an inducible promoter; and a recognition site for the endonuclease. The constructs may also include selectable markers for use in selecting recombinations.

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

NASA Technical Reports Server (NTRS)

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 simulations.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 simulatns.

Tissue-engineered cartilaginous constructs for the treatment of caprine cartilage defects, including distribution of laminin and type IV collagen.

PubMed

Jeng, Lily; Hsu, Hu-Ping; Spector, Myron

2013-10-01

The purpose of this study was the immunohistochemical evaluation of (1) cartilage tissue-engineered constructs; and (2) the tissue filling cartilage defects in a goat model into which the constructs were implanted, particularly for the presence of the basement membrane molecules, laminin and type IV collagen. Basement membrane molecules are localized to the pericellular matrix in normal adult articular cartilage, but have not been examined in tissue-engineered constructs cultured in vitro or in tissue filling cartilage defects into which the constructs were implanted. Cartilaginous constructs were engineered in vitro using caprine chondrocyte-seeded type II collagen scaffolds. Autologous constructs were implanted into 4-mm-diameter defects created to the tidemark in the trochlear groove in the knee joints of skeletally mature goats. Eight weeks after implantation, the animals were sacrificed. Constructs underwent immunohistochemical and histomorphometric evaluation. Widespread staining for the two basement membrane molecules was observed throughout the extracellular matrix of in vitro and in vivo samples in a distribution unlike that previously reported for cartilage. At sacrifice, 70% of the defect site was filled with reparative tissue, which consisted largely of fibrous tissue and some fibrocartilage, with over 70% of the reparative tissue bonded to the adjacent host tissue. A novel finding of this study was the observation of laminin and type IV collagen in in vitro engineered cartilaginous constructs and in vivo cartilage repair samples from defects into which the constructs were implanted, as well as in normal caprine articular cartilage. Future work is needed to elucidate the role of basement membrane molecules during cartilage repair and regeneration.

Tissue-Engineered Cartilaginous Constructs for the Treatment of Caprine Cartilage Defects, Including Distribution of Laminin and Type IV Collagen

PubMed Central

Jeng, Lily; Hsu, Hu-Ping

2013-01-01

The purpose of this study was the immunohistochemical evaluation of (1) cartilage tissue-engineered constructs; and (2) the tissue filling cartilage defects in a goat model into which the constructs were implanted, particularly for the presence of the basement membrane molecules, laminin and type IV collagen. Basement membrane molecules are localized to the pericellular matrix in normal adult articular cartilage, but have not been examined in tissue-engineered constructs cultured in vitro or in tissue filling cartilage defects into which the constructs were implanted. Cartilaginous constructs were engineered in vitro using caprine chondrocyte-seeded type II collagen scaffolds. Autologous constructs were implanted into 4-mm-diameter defects created to the tidemark in the trochlear groove in the knee joints of skeletally mature goats. Eight weeks after implantation, the animals were sacrificed. Constructs underwent immunohistochemical and histomorphometric evaluation. Widespread staining for the two basement membrane molecules was observed throughout the extracellular matrix of in vitro and in vivo samples in a distribution unlike that previously reported for cartilage. At sacrifice, 70% of the defect site was filled with reparative tissue, which consisted largely of fibrous tissue and some fibrocartilage, with over 70% of the reparative tissue bonded to the adjacent host tissue. A novel finding of this study was the observation of laminin and type IV collagen in in vitro engineered cartilaginous constructs and in vivo cartilage repair samples from defects into which the constructs were implanted, as well as in normal caprine articular cartilage. Future work is needed to elucidate the role of basement membrane molecules during cartilage repair and regeneration. PMID:23672504

14 CFR 33.17 - Fire protection.

Code of Federal Regulations, 2011 CFR

2011-01-01

... STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.17 Fire protection. (a) The design and... addition, the design and construction of turbine engines must minimize the probability of the occurrence of...

14 CFR 33.35 - Fuel and induction system.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Fuel and induction system. 33.35 Section 33... AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.35 Fuel and induction system. (a) The fuel system of the engine must be designed and constructed to supply an...

14 CFR 33.35 - Fuel and induction system.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Fuel and induction system. 33.35 Section 33... AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.35 Fuel and induction system. (a) The fuel system of the engine must be designed and constructed to supply an...

14 CFR 33.35 - Fuel and induction system.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Fuel and induction system. 33.35 Section 33... AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.35 Fuel and induction system. (a) The fuel system of the engine must be designed and constructed to supply an...

14 CFR 33.35 - Fuel and induction system.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Fuel and induction system. 33.35 Section 33... AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.35 Fuel and induction system. (a) The fuel system of the engine must be designed and constructed to supply an...

14 CFR 33.39 - Lubrication system.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Lubrication system. 33.39 Section 33.39... system. (a) The lubrication system of the engine must be designed and constructed so that it will... supply is in the engine. (b) The lubrication system of the engine must be designed and constructed to...

Design Guide for Selection and Specification of Kevlar Rope for Ocean Engineering and Construction.

DTIC Science & Technology

1976-07-01

public rtoieco cnd sol . It i Idim .buttm Is ul"rnimi.. OCEAN ENGINEERING AND CONSTRUCTION PROJECT OFFICE CHESAPEAKE DIVISION NAVAL FACILITIES ENGINEERING...be to have no more than one layer. This is impractical for oceano - graphic purposes. Assuming a need to spooi many layers of rope under tension

Tendon and ligament as novel cell sources for engineering the knee meniscus.

PubMed

Hadidi, P; Paschos, N K; Huang, B J; Aryaei, A; Hu, J C; Athanasiou, K A

2016-12-01

The application of cell-based therapies in regenerative medicine is hindered by the difficulty of acquiring adequate numbers of competent cells. For the knee meniscus in particular, this may be solved by harvesting tissue from neighboring tendons and ligaments. In this study, we have investigated the potential of cells from tendon and ligament, as compared to meniscus cells, to engineer scaffold-free self-assembling fibrocartilage. Self-assembling meniscus-shaped constructs engineered from a co-culture of articular chondrocytes and either meniscus, tendon, or ligament cells were cultured for 4 weeks with TGF-β1 in serum-free media. After culture, constructs were assessed for their mechanical properties, histological staining, gross appearance, and biochemical composition including cross-link content. Correlations were performed to evaluate relationships between biochemical content and mechanical properties. In terms of mechanical properties as well as biochemical content, constructs engineered using tenocytes and ligament fibrocytes were found to be equivalent or superior to constructs engineered using meniscus cells. Furthermore, cross-link content was found to be correlated with engineered tissue tensile properties. Tenocytes and ligament fibrocytes represent viable cell sources for engineering meniscus fibrocartilage using the self-assembling process. Due to greater cross-link content, fibrocartilage engineered with tenocytes and ligament fibrocytes may maintain greater tensile properties than fibrocartilage engineered with meniscus cells. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Tendon and ligament as novel cell sources for engineering the knee meniscus

PubMed Central

Hadidi, Pasha; Paschos, Nikolaos K.; Huang, Brian J.; Aryaei, Ashkan; Hu, Jerry C.; Athanasiou, Kyriacos A.

2016-01-01

Objective The application of cell-based therapies in regenerative medicine is hindered by the difficulty of acquiring adequate numbers of competent cells. For the knee meniscus in particular, this may be solved by harvesting tissue from neighboring tendons and ligaments. In this study, we have investigated the potential of cells from tendon and ligament, as compared to meniscus cells, to engineer scaffold-free self-assembling fibrocartilage. Method Self-assembling meniscus-shaped constructs engineered from a co-culture of articular chondrocytes and either meniscus, tendon, or ligament cells were cultured for 4 weeks with TGF-β1 in serum-free media. After culture, constructs were assessed for their mechanical properties, histological staining, gross appearance, and biochemical composition including cross-link content. Correlations were performed to evaluate relationships between biochemical content and mechanical properties. Results In terms of mechanical properties as well as biochemical content, constructs engineered using tenocytes and ligament fibrocytes were found to be equivalent or superior to constructs engineered using meniscus cells. Furthermore, cross-link content was found to be correlated with engineered tissue tensile properties. Conclusion Tenocytes and ligament fibrocytes represent viable cell sources for engineering meniscus fibrocartilage using the self-assembling process. Due to greater cross-link content, fibrocartilage engineered with tenocytes and ligament fibrocytes may maintain greater tensile properties than fibrocartilage engineered with meniscus cells. PMID:27473559

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

ERIC Educational Resources Information Center

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…

Construction Site Environmental Impact in Civil Engineering Education

ERIC Educational Resources Information Center

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…

78 FR 23837 - Cranes and Derricks in Construction: Underground Construction and Demolition

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-23

... report here the results for the entire heavy-and-civil engineering sector and the entire site... in this final rule because employers included in the heavy-and-civil engineering sector, or the site... final rule. This final rule affects two construction sectors: NAICS 237990 (Other Heavy and Civil...

Study on energy consumption evaluation of mountainous highway based on LCA

NASA Astrophysics Data System (ADS)

Fei, Lunlin; Zhang, Qi; Xie, Yongqing

2017-06-01

For the system to understand the road construction energy consumption process, this paper selects a typical mountainous highway in the south, using the theory and method of Life Cycle Assessment (LCA) to quantitatively study the energy consumption of the whole process of highway raw materials production, construction and operation. The results show that the energy consumption in the raw material production stage is the highest, followed by the highway operation and construction stage. The energy consumption per unit of tunnel engineering, bridge engineering, roadbed engineering and pavement engineering in the construction phase are 2279.00 tce, 1718.07 tce, 542.19 tce and 34.02 tce, and in operational phase, 85.44% of electricity consumption comes from tunnel ventilation and lighting. Therefore, in the bridge and tunnel construction process, we should promote energy-saving innovation of the construction technology and mechanical equipment, and further strengthen the research and development of tunnel ventilation, lighting energy-saving equipment and intelligent control technology, which will help significantly reduce the energy consumption and greenhouse gas emissions of the life cycle of highway.

Enhancing Knowledge Sharing Management Using BIM Technology in Construction

PubMed Central

Ho, Shih-Ping; Tserng, Hui-Ping

2013-01-01

Construction knowledge can be communicated and reused among project managers and jobsite engineers to alleviate problems on a construction jobsite and reduce the time and cost of solving problems related to constructability. This paper proposes a new methodology for the sharing of construction knowledge by using Building Information Modeling (BIM) technology. The main characteristics of BIM include illustrating 3D CAD-based presentations and keeping information in a digital format and facilitation of easy updating and transfer of information in the BIM environment. Using the BIM technology, project managers and engineers can gain knowledge related to BIM and obtain feedback provided by jobsite engineers for future reference. This study addresses the application of knowledge sharing management using BIM technology and proposes a BIM-based Knowledge Sharing Management (BIMKSM) system for project managers and engineers. The BIMKSM system is then applied in a selected case study of a construction project in Taiwan to demonstrate the effectiveness of sharing knowledge in the BIM environment. The results demonstrate that the BIMKSM system can be used as a visual BIM-based knowledge sharing management platform by utilizing the BIM technology. PMID:24723790

Enhancing knowledge sharing management using BIM technology in construction.

PubMed

Ho, Shih-Ping; Tserng, Hui-Ping; Jan, Shu-Hui

2013-01-01

Construction knowledge can be communicated and reused among project managers and jobsite engineers to alleviate problems on a construction jobsite and reduce the time and cost of solving problems related to constructability. This paper proposes a new methodology for the sharing of construction knowledge by using Building Information Modeling (BIM) technology. The main characteristics of BIM include illustrating 3D CAD-based presentations and keeping information in a digital format and facilitation of easy updating and transfer of information in the BIM environment. Using the BIM technology, project managers and engineers can gain knowledge related to BIM and obtain feedback provided by jobsite engineers for future reference. This study addresses the application of knowledge sharing management using BIM technology and proposes a BIM-based Knowledge Sharing Management (BIMKSM) system for project managers and engineers. The BIMKSM system is then applied in a selected case study of a construction project in Taiwan to demonstrate the effectiveness of sharing knowledge in the BIM environment. The results demonstrate that the BIMKSM system can be used as a visual BIM-based knowledge sharing management platform by utilizing the BIM technology.

Inspection of Construction Works According to Polish Construction Law

NASA Astrophysics Data System (ADS)

Czemplik, A.

2015-11-01

Construction regulations are still different in many European countries, even though the European Union directives have unified many acts for construction works and construction products in the member countries. The scheme of the construction process presented in the paper could be valid for most countries, despite of detailed regulations of legal systems. The number of construction regulations to be followed in order to get the Construction Permit in Poland is rather big, so the time between the start of the investment process and the day when the Construction Permit is issued could be several months. Only licensed professional engineers can play the role of site managers, site inspectors and designers, registered for the given construction project. Duties and responsibilities (civil liability) of these engineers are strictly defined by regulations. The obligatory inspection of construction works should be executed by the licensed site inspectors. Moreover, the works can be incidentally inspected by Authority, banks, insurance companies or designers. Foreign designers and foreign site engineers in order to be allowed by respective Authority to play official roles on Polish construction sites should present documents proving that they can do the same jobs in their countries as per regulations obligatory there.

An Analysis of Cost Premiums and Losses Associated with USAF Military Construction (MILCON)

DTIC Science & Technology

2013-03-01

Corps of Engineers (USACE) or the Naval Facilities Engineering Command (NAVFAC) for design and construction of the annual military construction...AFCEC in lieu of AFCEE or AFCESA. The selection, and policies, of design and construction agents may cause cost premiums for Air Force MILCON...private industry best practices such as relational contracting, schedule performance, and design -build procurement methods. All of these research

Evaluation of Glass Fiber Reinforced Concrete Panels for Use in Military Construction.

DTIC Science & Technology

1984-06-01

AD-A158 134 UNCLASSIFIED EVALUATION OF GLASS FIBER REINFORCED CONCRETE PANELS FOR USE IN MILITARY. . (U) CONSTRUCTION ENGINEERING RESEARCH LAB...Construction Engineering Research Laboratory i=h-C=iU. TECHNICAL REPORT M-85/15 June 1985 AD-A158 134 0~- 8 Evaluation of Glass Fiber ...Reinforced Concrete Panels for Use in Military Construction by Gilbert R. Williamson Glass fiber reinforced concrete (GFRC) materials are investigated

Wood products used in constructing conservation and development projects by the Corps of Engineers in the United States, 1962 and 1978

Treesearch

W. H. Reid; D. B. McKeever

Estimates of the amounts of wood products used in constructing civil conservation and development projects by the Corps of Engineers in the United States are presented for the years 1962 and 1978. Amounts of lumber, laminated lumber, poles and piling, and plywood used in construction are stratified by five construction categories, and three types of uses. Estimates of...

[Development of computer aided forming techniques in manufacturing scaffolds for bone tissue engineering].

PubMed

Wei, Xuelei; Dong, Fuhui

2011-12-01

To review recent advance in the research and application of computer aided forming techniques for constructing bone tissue engineering scaffolds. The literature concerning computer aided forming techniques for constructing bone tissue engineering scaffolds in recent years was reviewed extensively and summarized. Several studies over last decade have focused on computer aided forming techniques for bone scaffold construction using various scaffold materials, which is based on computer aided design (CAD) and bone scaffold rapid prototyping (RP). CAD include medical CAD, STL, and reverse design. Reverse design can fully simulate normal bone tissue and could be very useful for the CAD. RP techniques include fused deposition modeling, three dimensional printing, selected laser sintering, three dimensional bioplotting, and low-temperature deposition manufacturing. These techniques provide a new way to construct bone tissue engineering scaffolds with complex internal structures. With rapid development of molding and forming techniques, computer aided forming techniques are expected to provide ideal bone tissue engineering scaffolds.

3D bioprinting for vascularized tissue fabrication

PubMed Central

Richards, Dylan; Jia, Jia; Yost, Michael; Markwald, Roger; Mei, Ying

2016-01-01

3D bioprinting holds remarkable promise for rapid fabrication of 3D tissue engineering constructs. Given its scalability, reproducibility, and precise multi-dimensional control that traditional fabrication methods do not provide, 3D bioprinting provides a powerful means to address one of the major challenges in tissue engineering: vascularization. Moderate success of current tissue engineering strategies have been attributed to the current inability to fabricate thick tissue engineering constructs that contain endogenous, engineered vasculature or nutrient channels that can integrate with the host tissue. Successful fabrication of a vascularized tissue construct requires synergy between high throughput, high-resolution bioprinting of larger perfusable channels and instructive bioink that promotes angiogenic sprouting and neovascularization. This review aims to cover the recent progress in the field of 3D bioprinting of vascularized tissues. It will cover the methods of bioprinting vascularized constructs, bioink for vascularization, and perspectives on recent innovations in 3D printing and biomaterials for the next generation of 3D bioprinting for vascularized tissue fabrication. PMID:27230253

Closed-loop recycling of construction and demolition waste in Germany in view of stricter environmental threshold values.

PubMed

Weil, Marcel; Jeske, Udo; Schebek, Liselotte

2006-06-01

Recycling of construction and demolition waste contributes decisively to the saving of natural mineral resources. In Germany, processed mineral construction and demolition waste from structural engineering is used nearly exclusively in civil engineering (earthwork and road construction sector) as open-loop recycling. Due to the planned stricter limit values for the protection of soil and water, however, this recycling path in civil engineering may no longer be applicable in the future. According to some new guidelines and standards adopted recently, recycled aggregates may also be used for concrete production in the structural engineering sector (closed-loop recycling). Wastes from the structural engineering sector can thus be kept in a closed cycle, and their disposal on a landfill can be avoided. The present report focuses on the determination of maximum waste volumes that may be handled by this new recycling option. Potential adverse effects on the saving of resources and climate protection have been analysed. For this purpose, materials flow analysis and ecobalancing methods have been used.

Technician Career Opportunities in Engineering Technology.

ERIC Educational Resources Information Center

Engineers' Council for Professional Development, New York, NY.

Career opportunities for engineering technicians are available in the technologies relating to air conditioning, heating, and refrigeration, aviation and aerospace, building construction, chemical engineering, civil engineering, electrical engineering, electronics, industrial engineering, instrumentation, internal combustion engines, mechanical…

Differential osteogenic activity of osteoprogenitor cells on HA and TCP/HA scaffold of tissue engineered bone.

PubMed

Ng, Angela M H; Tan, K K; Phang, M Y; Aziyati, O; Tan, G H; Isa, M R; Aminuddin, B S; Naseem, M; Fauziah, O; Ruszymah, B H I

2008-05-01

Biomaterial, an essential component of tissue engineering, serves as a scaffold for cell attachment, proliferation, and differentiation; provides the three dimensional (3D) structure and, in some applications, the mechanical strength required for the engineered tissue. Both synthetic and naturally occurring calcium phosphate based biomaterial have been used as bone fillers or bone extenders in orthopedic and reconstructive surgeries. This study aims to evaluate two popular calcium phosphate based biomaterial i.e., hydroxyapatite (HA) and tricalcium phosphate/hydroxyapatite (TCP/HA) granules as scaffold materials in bone tissue engineering. In our strategy for constructing tissue engineered bone, human osteoprogenitor cells derived from periosteum were incorporated with human plasma-derived fibrin and seeded onto HA or TCP/HA forming 3D tissue constructs and further maintained in osteogenic medium for 4 weeks to induce osteogenic differentiation. Constructs were subsequently implanted intramuscularly in nude mice for 8 weeks after which mice were euthanized and constructs harvested for evaluation. The differential cell response to the biomaterial (HA or TCP/HA) adopted as scaffold was illustrated by the histology of undecalcified constructs and evaluation using SEM and TEM. Both HA and TCP/HA constructs showed evidence of cell proliferation, calcium deposition, and collagen bundle formation albeit lesser in the former. Our findings demonstrated that TCP/HA is superior between the two in early bone formation and hence is the scaffold material of choice in bone tissue engineering. Copyright 2007 Wiley Periodicals, Inc.

In vitro engineering of fibrocartilage using CDMP1 induced dermal fibroblasts and polyglycolide.

PubMed

Zhao, Guiqing; Yin, Shuo; Liu, Guangpeng; Cen, Lian; Sun, Jian; Zhou, Heng; Liu, Wei; Cui, Lei; Cao, Yilin

2009-07-01

This study was designed to explore the feasibility of using cartilage-derived morphogenetic protein-1 (CDMP1) induced dermal fibroblasts (DFs) as seed cells and polyglycolide (PGA) as scaffold for fibrocartilage engineering. DFs isolated from canine were expanded and seeded on PGA scaffold to fabricate cell/scaffold constructs which were cultured with or without CDMP1. Proliferation and differentiation of DFs in different constructs were determined by DNA assay and glycosaminoglycan (GAG) production. Histological and immunohistochemical staining of the constructs after being in vitro cultured for 4 and 6 weeks were carried out to observe the fibrocartilage formation condition. The fibrocartilage-specific gene expression by cells in the constructs was analyzed by real-time PCR. It was shown that in the presence of CDMP1 the proliferation and GAG synthesis of DFs were significantly enhanced compared to those without CDMP1. Fibrocartilage-like tissue was formed in the CDMP1 induced construct after being cultured for 4 weeks, and it became more matured at 6 weeks as stronger staining for GAG and higher gene expression of collagen type II was observed. Since only weak staining for GAG and collagen type II was observed for the construct engineered without CDMP1, the induction effect on the fibrocartilage engineering can be ascertained when using DFs as seed cells. Furthermore, the potential of using DFs as seed cells to engineer fibrocartilage is substantiated and further study on using the engineered tissue to repair fibrocartilage defects is currently ongoing in our group.

Management and integration of engineering and construction activities: Lessons learned from the AP1000{sup R} nuclear power plant China project

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

McCullough, M. C.; Ebeling-Koning, D.; Evans, M. C.

2012-07-01

The lessons learned during the early phase of design engineering and construction activities for the AP1000 China Project can be applied to any project involving multiple disciplines and multiple organizations. Implementation of a first-of-a-kind design to directly support construction activities utilizing resources assigned to design development and design delivery creates challenges with prioritization of activities, successful closure of issues, and communication between site organizations and the home office. To ensure successful implementation, teams were assigned and developed to directly support construction activities including prioritization of activities, site communication and ensuring closure of site emergent issues. By developing these teams, themore » organization is better suited to meet the demands of the construction schedule while continuing with design evolution of a standard plant and engineering delivery for multiple projects. For a successful project, proper resource utilization and prioritization are key for overcoming obstacles and ensuring success of the engineering organization. (authors)« less

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

PubMed

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.

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

ERIC Educational Resources Information Center

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…

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

ERIC Educational Resources Information Center

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…

Knowledge, attitude and practices for design for safety: A study on civil & structural engineers.

PubMed

Goh, Yang Miang; Chua, Sijie

2016-08-01

Design for safety (DfS) (also known as prevention through design, safe design and Construction (Design and Management)) promotes early consideration of safety and health hazards during the design phase of a construction project. With early intervention, hazards can be more effectively eliminated or controlled leading to safer worksites and construction processes. DfS is practiced in many countries, including Australia, the UK, and Singapore. In Singapore, the Manpower Ministry enacted the DfS Regulations in July 2015, which will be enforced from August 2016 onwards. Due to the critical role of civil and structural (C&S) engineers during design and construction, the DfS knowledge, attitude and practices (KAP) of C&S engineers have significant impact on the successful implementation of DfS. Thus, this study aims to explore the DfS KAP of C&S engineers so as to guide further research in measuring and improving DfS KAP of designers. During the study, it was found that there is a lack of KAP studies in construction management. Therefore, this study also aims to provide useful lessons for future applications of the KAP framework in construction management research. A questionnaire was developed to assess the DfS KAP of C&S engineers. The responses provided by 43 C&S engineers were analyzed. In addition, interviews with experienced construction professionals were carried out to further understand perceptions of DfS and related issues. The results suggest that C&S engineers are supportive of DfS, but the level of DfS knowledge and practices need to be improved. More DfS guidelines and training should be made available to the engineers. To ensure that DfS can be implemented successfully, there is a need to study the contractual arrangements between clients and designers and the effectiveness of different implementation approaches for the DfS process. The questionnaire and findings in this study provided the foundation for a baseline survey with larger sample size, which is currently being planned. In contrast to earlier studies, the study showed that the responding C&S engineers were supportive of the DfS. The study showed that the key to improving the DfS KAP of C&S engineers is by improving clients' motivation for DfS. Copyright © 2015 Elsevier Ltd. All rights reserved.

48 CFR 36.601-4 - Implementation.

Code of Federal Regulations, 2010 CFR

2010-10-01

... engineering nature associated with design or construction of real property. (3) Other professional services of..., investigations, surveying and mapping, tests, evaluations, consultations, comprehensive planning, program management, conceptual designs, plans and specifications, value engineering, construction phase services...

48 CFR 36.601-4 - Implementation.

Code of Federal Regulations, 2014 CFR

2014-10-01

... engineering nature associated with design or construction of real property. (3) Other professional services of..., investigations, surveying and mapping, tests, evaluations, consultations, comprehensive planning, program management, conceptual designs, plans and specifications, value engineering, construction phase services...

48 CFR 36.601-4 - Implementation.

Code of Federal Regulations, 2011 CFR

2011-10-01

... engineering nature associated with design or construction of real property. (3) Other professional services of..., investigations, surveying and mapping, tests, evaluations, consultations, comprehensive planning, program management, conceptual designs, plans and specifications, value engineering, construction phase services...

48 CFR 36.601-4 - Implementation.

Code of Federal Regulations, 2013 CFR

2013-10-01

... engineering nature associated with design or construction of real property. (3) Other professional services of..., investigations, surveying and mapping, tests, evaluations, consultations, comprehensive planning, program management, conceptual designs, plans and specifications, value engineering, construction phase services...

48 CFR 36.601-4 - Implementation.

Code of Federal Regulations, 2012 CFR

2012-10-01

... engineering nature associated with design or construction of real property. (3) Other professional services of..., investigations, surveying and mapping, tests, evaluations, consultations, comprehensive planning, program management, conceptual designs, plans and specifications, value engineering, construction phase services...

Construction engineering inspection direct cost survey.

DOT National Transportation Integrated Search

2014-07-01

The objective of the study was to provide a rationale to Georgia Department of Transportation : (GDOT) for Direct Costs in terms of salary and wages charged by qualified independent : contractors performing Construction Engineering Inspection (CEI) s...

14 CFR 23.1193 - Cowling and nacelle.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) Each cowling must be constructed and supported so that it can resist any vibration, inertia, and air... engines must be designed and constructed so that with the landing gear retracted, a fire in the engine...

Purpose-driven biomaterials research in liver-tissue engineering.

PubMed

Ananthanarayanan, Abhishek; Narmada, Balakrishnan Chakrapani; Mo, Xuejun; McMillian, Michael; Yu, Hanry

2011-03-01

Bottom-up engineering of microscale tissue ("microtissue") constructs to recapitulate partially the complex structure-function relationships of liver parenchyma has been realized through the development of sophisticated biomaterial scaffolds, liver-cell sources, and in vitro culture techniques. With regard to in vivo applications, the long-lived stem/progenitor cell constructs can improve cell engraftment, whereas the short-lived, but highly functional hepatocyte constructs stimulate host liver regeneration. With regard to in vitro applications, microtissue constructs are being adapted or custom-engineered into cell-based assays for testing acute, chronic and idiosyncratic toxicities of drugs or pathogens. Systems-level methods and computational models that represent quantitative relationships between biomaterial scaffolds, cells and microtissue constructs will further enable their rational design for optimal integration into specific biomedical applications. Copyright © 2010 Elsevier Ltd. All rights reserved.

Towards organ printing: engineering an intra-organ branched vascular tree.

PubMed

Visconti, Richard P; Kasyanov, Vladimir; Gentile, Carmine; Zhang, Jing; Markwald, Roger R; Mironov, Vladimir

2010-03-01

Effective vascularization of thick three-dimensional engineered tissue constructs is a problem in tissue engineering. As in native organs, a tissue-engineered intra-organ vascular tree must be comprised of a network of hierarchically branched vascular segments. Despite this requirement, current tissue-engineering efforts are still focused predominantly on engineering either large-diameter macrovessels or microvascular networks. We present the emerging concept of organ printing or robotic additive biofabrication of an intra-organ branched vascular tree, based on the ability of vascular tissue spheroids to undergo self-assembly. The feasibility and challenges of this robotic biofabrication approach to intra-organ vascularization for tissue engineering based on organ-printing technology using self-assembling vascular tissue spheroids including clinically relevantly vascular cell sources are analyzed. It is not possible to engineer 3D thick tissue or organ constructs without effective vascularization. An effective intra-organ vascular system cannot be built by the simple connection of large-diameter vessels and microvessels. Successful engineering of functional human organs suitable for surgical implantation will require concomitant engineering of a 'built in' intra-organ branched vascular system. Organ printing enables biofabrication of human organ constructs with a 'built in' intra-organ branched vascular tree.

Mineralization Induction of Gingival Fibroblasts and Construction of a Sandwich Tissue-Engineered Complex for Repairing Periodontal Defects

PubMed Central

Wu, Mingxuan; Zhang, Yanning; Liu, Huijuan; Dong, Fusheng

2018-01-01

Background The ideal healing technique for periodontal tissue defects would involve the functional regeneration of the alveolar bone, cementum, and periodontal ligament, with new periodontal attachment formation. In this study, gingival fibroblasts were induced and a “sandwich” tissue-engineered complex (a tissue-engineered periodontal membrane between 2 tissue-engineered mineralized membranes) was constructed to repair periodontal defects. We evaluated the effects of gingival fibroblasts used as seed cells on the repair of periodontal defects and periodontal regeneration. Material/Methods Primitively cultured gingival fibroblasts were seeded bilaterally on Bio-Gide collagen membrane (a tissue-engineered periodontal membrane) or unilaterally on small intestinal submucosa segments, and their mineralization was induced. A tissue-engineered sandwich was constructed, comprising the tissue-engineered periodontal membrane flanked by 2 mineralized membranes. Periodontal defects in premolar regions of Beagles were repaired using the tissue-engineered sandwich or periodontal membranes. Periodontal reconstruction was compared to normal and trauma controls 10 or 20 days postoperatively. Results Periodontal defects were completely repaired by the sandwich tissue-engineered complex, with intact new alveolar bone and cementum, and a new periodontal ligament, 10 days postoperatively. Conclusions The sandwich tissue-engineered complex can achieve ideal periodontal reconstruction rapidly. PMID:29470454

An Exploratory Study of Students' Constructions of Gender in Science, Engineering and Technology

ERIC Educational Resources Information Center

Lynch, Ingrid; Nowosenetz, Tessa

2009-01-01

Despite an appreciation of the need to increase gender sensitivity and awareness among tertiary students in the field of science, engineering and technology (SET), there is a paucity of research that explores how students in this field construct gender. A greater understanding of such constructions can assist in transforming gender relations and…

Assessing Students' Sentiments towards the Use of a Building Information Modelling (BIM) Learning Platform in a Construction Project Management Course

ERIC Educational Resources Information Center

Suwal, Sunil; Singh, Vishal

2018-01-01

Building Information Modelling (BIM) tools and processes are increasingly adopted and implemented in the construction industry. Consequently, BIM education is considered increasingly important in Architecture, Engineering and Construction (AEC) education. While most of the research and literature on BIM education in engineering studies has focused…

An Analysis of Insulated Concrete Forms for use in Sustainable Military Construction

DTIC Science & Technology

2014-03-27

CONSTRUCTION THESIS Presented to the Faculty Department of Systems and Engineering Management Graduate School of Engineering and Management...which fit together and are filled with reinforced concrete to construct the exterior wall systems of a building. By design, this material provides a...Forms with Rebar .............................................................. 12 Figure 3. Cut outs of ICF wall systems

Identifying Indicators Related to Constructs for Engineering Design Outcome

ERIC Educational Resources Information Center

Wilhelmsen, Cheryl A.; Dixon, Raymond A.

2016-01-01

This study ranked constructs articulated by Childress and Rhodes (2008) and identified the key indicators for each construct as a starting point to explore what should be included on an instrument to measure the engineering design process and outcomes of students in high schools that use the PLTW and EbDTM curricula in Idaho. A case-study design…

REACTOR SERVICE BUILDING, TRA635, CONTEXTUAL VIEW DURING CONSTRUCTION. CAMERA IS ...

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

REACTOR SERVICE BUILDING, TRA-635, CONTEXTUAL VIEW DURING CONSTRUCTION. CAMERA IS ATOP MTR BUILDING AND LOOKING SOUTHERLY. FOUNDATION AND DRAINS ARE UNDER CONSTRUCTION. THE BUILDING WILL BUTT AGAINST CHARGING FACE OF PLUG STORAGE BUILDING. HOT CELL BUILDING, TRA-632, IS UNDER CONSTRUCTION AT TOP CENTER OF VIEW. INL NEGATIVE NO. 8518. Unknown Photographer, 8/25/1953 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Final Report on the Audit of Architect-Engineer Contracting at the Officer in Charge of Construction, Naval Facilities Engineering Command Contracts, Mediterranean, Madrid, Spain

DTIC Science & Technology

1990-11-30

This is our final report on the audit of Architect-Engineer Contracting for the Officer in Charge of Construction, Naval Facilities Engineering...Command Contracts, Mediterranean, for your information and use. This is the fourth in a series of reports issued as part of the audit of architect-engineer...A-E) contracting. The Contract Management Directorate made the audit from August 1989 through July 1990. When we expanded the audit scope to include

58. Photographic copy of original construction plan (St. Paul Engineer's ...

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

58. Photographic copy of original construction plan (St. Paul Engineer's Office, Wabasha St. Bridge, Plan of Masonry, February 1899); south abutment - Wabasha Street Bridge, Spanning Mississippi River at Wabasha Street, Saint Paul, Ramsey County, MN

Railway project design and construction (CEE 411) course updates.

DOT National Transportation Integrated Search

2017-01-20

Course CEE 411 "Railway Project Design and Construction" is a cornerstone of the railway : engineering education program developed by the Rail Transportation and Engineering Center : (RailTEC) at the University of Illinois at Urbana-Champaign (UIUC)....

Fibrin gels exhibit improved biological, structural, and mechanical properties compared with collagen gels in cell-based tendon tissue-engineered constructs.

PubMed

Breidenbach, Andrew P; Dyment, Nathaniel A; Lu, Yinhui; Rao, Marepalli; Shearn, Jason T; Rowe, David W; Kadler, Karl E; Butler, David L

2015-02-01

The prevalence of tendon and ligament injuries and inadequacies of current treatments is driving the need for alternative strategies such as tissue engineering. Fibrin and collagen biopolymers have been popular materials for creating tissue-engineered constructs (TECs), as they exhibit advantages of biocompatibility and flexibility in construct design. Unfortunately, a few studies have directly compared these materials for tendon and ligament applications. Therefore, this study aims at determining how collagen versus fibrin hydrogels affect the biological, structural, and mechanical properties of TECs during formation in vitro. Our findings show that tendon and ligament progenitor cells seeded in fibrin constructs exhibit improved tenogenic gene expression patterns compared with their collagen-based counterparts for approximately 14 days in culture. Fibrin-based constructs also exhibit improved cell-derived collagen alignment, increased linear modulus (2.2-fold greater) compared with collagen-based constructs. Cyclic tensile loading, which promotes the maturation of tendon constructs in a previous work, exhibits a material-dependent effect in this study. Fibrin constructs show trending reductions in mechanical, biological, and structural properties, whereas collagen constructs only show improved tenogenic expression in the presence of mechanical stimulation. These findings highlight that components of the mechanical stimulus (e.g., strain amplitude or time of initiation) need to be tailored to the material and cell type. Given the improvements in tenogenic expression, extracellular matrix organization, and material properties during static culture, in vitro findings presented here suggest that fibrin-based constructs may be a more suitable alternative to collagen-based constructs for tissue-engineered tendon/ligament repair.

Fibrin Gels Exhibit Improved Biological, Structural, and Mechanical Properties Compared with Collagen Gels in Cell-Based Tendon Tissue-Engineered Constructs

PubMed Central

Dyment, Nathaniel A.; Lu, Yinhui; Rao, Marepalli; Shearn, Jason T.; Rowe, David W.; Kadler, Karl E.; Butler, David L.

2015-01-01

The prevalence of tendon and ligament injuries and inadequacies of current treatments is driving the need for alternative strategies such as tissue engineering. Fibrin and collagen biopolymers have been popular materials for creating tissue-engineered constructs (TECs), as they exhibit advantages of biocompatibility and flexibility in construct design. Unfortunately, a few studies have directly compared these materials for tendon and ligament applications. Therefore, this study aims at determining how collagen versus fibrin hydrogels affect the biological, structural, and mechanical properties of TECs during formation in vitro. Our findings show that tendon and ligament progenitor cells seeded in fibrin constructs exhibit improved tenogenic gene expression patterns compared with their collagen-based counterparts for approximately 14 days in culture. Fibrin-based constructs also exhibit improved cell-derived collagen alignment, increased linear modulus (2.2-fold greater) compared with collagen-based constructs. Cyclic tensile loading, which promotes the maturation of tendon constructs in a previous work, exhibits a material-dependent effect in this study. Fibrin constructs show trending reductions in mechanical, biological, and structural properties, whereas collagen constructs only show improved tenogenic expression in the presence of mechanical stimulation. These findings highlight that components of the mechanical stimulus (e.g., strain amplitude or time of initiation) need to be tailored to the material and cell type. Given the improvements in tenogenic expression, extracellular matrix organization, and material properties during static culture, in vitro findings presented here suggest that fibrin-based constructs may be a more suitable alternative to collagen-based constructs for tissue-engineered tendon/ligament repair. PMID:25266738

Mechanics of oriented electrospun nanofibrous scaffolds for annulus fibrosus tissue engineering.

PubMed

Nerurkar, Nandan L; Elliott, Dawn M; Mauck, Robert L

2007-08-01

Engineering a functional replacement for the annulus fibrosus (AF) of the intervertebral disc is contingent upon recapitulation of AF structure, composition, and mechanical properties. In this study, we propose a new paradigm for AF tissue engineering that focuses on the reconstitution of anatomic fiber architecture and uses constitutive modeling to evaluate construct function. A modified electrospinning technique was utilized to generate aligned nanofibrous polymer scaffolds for engineering the basic functional unit of the AF, a single lamella. Scaffolds were tested in uniaxial tension at multiple fiber orientations, demonstrating a nonlinear dependence of modulus on fiber angle that mimicked the nonlinearity and anisotropy of native AF. A homogenization model previously applied to native AF successfully described scaffold mechanical response, and parametric studies demonstrated that nonfibrillar matrix, along with fiber connectivity, are key contributors to tensile mechanics for engineered AF. We demonstrated that AF cells orient themselves along the aligned scaffolds and deposit matrix that contributes to construct mechanics under loading conditions relevant to the in vivo environment. The homogenization model was applied to cell-seeded constructs and provided quantitative measures for the evolution of matrix and interfibrillar interactions. Finally, the model demonstrated that at fiber angles of the AF (28 degrees -44 degrees ), engineered material behaved much like native tissue, suggesting that engineered constructs replicate the physiologic behavior of the single AF lamella. Constitutive modeling provides a powerful tool for analysis of engineered AF neo-tissue and native AF tissue alike, highlighting key mechanical design criteria for functional AF tissue engineering.

Constructively Aligned Teaching and Learning in Higher Education in Engineering: What Do Students Perceive as Contributing to the Learning of Interdisciplinary Thinking?

ERIC Educational Resources Information Center

Spelt, E. J. H.; Luning, P. A.; van Boekel, M. A. J. S.; Mulder, M.

2015-01-01

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 engineering. Therefore, the present design-based…

The Expanding World of Tissue Engineering: The Building Blocks and New Applications of Tissue Engineered Constructs

PubMed Central

Zorlutuna, Pinar; Vrana, Nihal Engin; Khademhosseini, Ali

2013-01-01

The field of tissue engineering has been growing in the recent years as more products have made it to the market and as new uses for the engineered tissues have emerged, motivating many researchers to engage in this multidisciplinary field of research. Engineered tissues are now not only considered as end products for regenerative medicine, but also have emerged as enabling technologies for other fields of research ranging from drug discovery to biorobotics. This widespread use necessitates a variety of methodologies for production of tissue engineered constructs. In this review, these methods together with their non-clinical applications will be described. First, we will focus on novel materials used in tissue engineering scaffolds; such as recombinant proteins and synthetic, self assembling polypeptides. The recent advances in the modular tissue engineering area will be discussed. Then scaffold-free production methods, based on either cell sheets or cell aggregates will be described. Cell sources used in tissue engineering and new methods that provide improved control over cell behavior such as pathway engineering and biomimetic microenvironments for directing cell differentiation will be discussed. Finally, we will summarize the emerging uses of engineered constructs such as model tissues for drug discovery, cancer research and biorobotics applications. PMID:23268388

This photographic copy of an engineering drawing shows floor plans, ...

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

This photographic copy of an engineering drawing shows floor plans, sections and elevations of Building E-86, with details typical of the steel frame and "Transite" building construction at JPL Edwards Facility. California Institute of Technology, Jet Propulsion Laboratory, Facilities Engineering and Construction Office: "Casting & Curing, Building E-86, Floor Plan, Elevations & Section," drawing no. E86/6, 25 February 1977. California Institute of Technology, Jet Propulsion Laboratory, Plant Engineering: engineering drawings of structures at JPL Edwards Facility. Drawings on file at JPL Plant Engineering, Pasadena, California - Jet Propulsion Laboratory Edwards Facility, Casting & Curing Building, Edwards Air Force Base, Boron, Kern County, CA

10 CFR 609.12 - Project Costs.

Code of Federal Regulations, 2011 CFR

2011-01-01

... incurred in the design, engineering, financing, construction, startup, commissioning and shakedown of the... rental of real property, including engineering fees, surveys, title insurance, recording fees, and legal... transportation for facility design, construction, startup, commissioning and shakedown; (3) Costs of equipment...

10 CFR 609.12 - Project Costs.

Code of Federal Regulations, 2012 CFR

2012-01-01

... incurred in the design, engineering, financing, construction, startup, commissioning and shakedown of the... rental of real property, including engineering fees, surveys, title insurance, recording fees, and legal... transportation for facility design, construction, startup, commissioning and shakedown; (3) Costs of equipment...

10 CFR 609.12 - Project Costs.

Code of Federal Regulations, 2013 CFR

2013-01-01

... incurred in the design, engineering, financing, construction, startup, commissioning and shakedown of the... rental of real property, including engineering fees, surveys, title insurance, recording fees, and legal... transportation for facility design, construction, startup, commissioning and shakedown; (3) Costs of equipment...

10 CFR 609.12 - Project Costs.

Code of Federal Regulations, 2010 CFR

2010-01-01

... incurred in the design, engineering, financing, construction, startup, commissioning and shakedown of the... rental of real property, including engineering fees, surveys, title insurance, recording fees, and legal... transportation for facility design, construction, startup, commissioning and shakedown; (3) Costs of equipment...

10 CFR 609.12 - Project Costs.

Code of Federal Regulations, 2014 CFR

2014-01-01

... incurred in the design, engineering, financing, construction, startup, commissioning and shakedown of the... rental of real property, including engineering fees, surveys, title insurance, recording fees, and legal... transportation for facility design, construction, startup, commissioning and shakedown; (3) Costs of equipment...

The influence of construct scale on the composition and functional properties of cartilaginous tissues engineered using bone marrow-derived mesenchymal stem cells.

PubMed

Buckley, Conor T; Meyer, Eric G; Kelly, Daniel J

2012-02-01

Engineering cartilaginous tissue of a scale necessary to treat defects observed clinically is a well-documented challenge in the field of cartilage tissue engineering. The objective of this study was to determine how the composition and mechanical properties of cartilaginous tissues that are engineered by using bone marrow-derived mesenchymal stem cells (MSCs) depend on the scale of the construct. Porcine bone marrow-derived MSCs were encapsulated in agarose hydrogels, and constructs of different cylindrical geometries (Ø4×1.5 mm; Ø5×3 mm; Ø6×4.5 mm; Ø8×4.5 mm) were fabricated and maintained in a chemically defined serum-free medium supplemented with transforming growth factor-β3 for 42 days. Total sulfated glycosaminoglycan (sGAG) accumulation by day 42 increased from 0.14% w/w to 0.88% w/w as the construct geometry increased from Ø4×1.5 to Ø8×4.5 mm, with collagen accumulation increasing from 0.31% w/w to 1.62% w/w. This led to an increase in the dynamic modulus from 90.81 to 327.51 kPa as the engineered tissue increased in scale from Ø4×1.5 to Ø8×4.5 mm. By decreasing the external oxygen tension from 20% to 5%, it was possible to achieve these higher levels of mechanical functionality in the smaller engineered tissues. Constructs were then sectioned into smaller subregions to quantify the spatial accumulation of extracellular matrix components, and a model of oxygen diffusion and consumption was used to predict spatial gradients in oxygen concentration throughout the construct. sGAG accumulation was always highest in regions where oxygen concentration was predicted to be lowest. In addition, as the size of the engineered construct increased, different regions of the construct preferentially supported either sGAG or collagen accumulation, thus suggesting that gradients in regulatory factors other than oxygen were playing a role in determining levels of collagen synthesis. The identification of such factors and the means to control their spatial concentration within developing tissues represents a central challenge in engineering large cartilaginous grafts.

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.

PubMed

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Engineering tubular bone using mesenchymal stem cell sheets and coral particles

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

Geng, Wenxin; Ma, Dongyang; Yan, Xingrong

Highlights: • We developed a novel engineering strategy to solve the limitations of bone grafts. • We fabricated tubular constructs using cell sheets and coral particles. • The composite constructs showed high radiological density and compressive strength. • These characteristics were similar to those of native bone. -- Abstract: The development of bone tissue engineering has provided new solutions for bone defects. However, the cell-scaffold-based approaches currently in use have several limitations, including low cell seeding rates and poor bone formation capacity. In the present study, we developed a novel strategy to engineer bone grafts using mesenchymal stem cell sheetsmore » and coral particles. Rabbit bone marrow mesenchymal stem cells were continuously cultured to form a cell sheet with osteogenic potential and coral particles were integrated into the sheet. The composite sheet was then wrapped around a cylindrical mandrel to fabricate a tubular construct. The resultant tubular construct was cultured in a spinner-flask bioreactor and subsequently implanted into a subcutaneous pocket in a nude mouse for assessment of its histological characteristics, radiological density and mechanical property. A similar construct assembled from a cell sheet alone acted as a control. In vitro observations demonstrated that the composite construct maintained its tubular shape, and exhibited higher radiological density, compressive strength and greater extracellular matrix deposition than did the control construct. In vivo experiments further revealed that new bone formed ectopically on the composite constructs, so that the 8-week explants of the composite sheets displayed radiological density similar to that of native bone. These results indicate that the strategy of using a combination of a cell sheet and coral particles has great potential for bone tissue engineering and repairing bone defects.« less

Factors affecting the structure and maturation of human tissue engineered skeletal muscle.

PubMed

Martin, Neil R W; Passey, Samantha L; Player, Darren J; Khodabukus, Alastair; Ferguson, Richard A; Sharples, Adam P; Mudera, Vivek; Baar, Keith; Lewis, Mark P

2013-07-01

Tissue engineered skeletal muscle has great utility in experimental studies of physiology, clinical testing and its potential for transplantation to replace damaged tissue. Despite recent work in rodent tissue or cell lines, there is a paucity of literature concerned with the culture of human muscle derived cells (MDCs) in engineered constructs. Here we aimed to tissue engineer for the first time in the literature human skeletal muscle in self-assembling fibrin hydrogels and determine the effect of MDC seeding density and myogenic proportion on the structure and maturation of the constructs. Constructs seeded with 4 × 10(5) MDCs assembled to a greater extent than those at 1 × 10(5) or 2 × 10(5), and immunostaining revealed a higher fusion index and a higher density of myotubes within the constructs, showing greater structural semblance to in vivo tissue. These constructs primarily expressed perinatal and slow type I myosin heavy chain mRNA after 21 days in culture. In subsequent experiments MACS(®) technology was used to separate myogenic and non-myogenic cells from their heterogeneous parent population and these cells were seeded at varying myogenic (desmin +) proportions in fibrin based constructs. Only in the constructs seeded with 75% desmin + cells was there evidence of striations when immunostained for slow myosin heavy chain compared with constructs seeded with 10 or 50% desmin + cells. Overall, this work reveals the importance of cell number and myogenic proportions in tissue engineering human skeletal muscle with structural resemblance to in vivo tissue. Copyright © 2013 Elsevier Ltd. All rights reserved.

Anatomically shaped tissue-engineered cartilage with tunable and inducible anticytokine delivery for biological joint resurfacing

PubMed Central

Moutos, Franklin T.; Glass, Katherine A.; Compton, Sarah A.; Ross, Alison K.; Gersbach, Charles A.; Estes, Bradley T.

2016-01-01

Biological resurfacing of entire articular surfaces represents an important but challenging strategy for treatment of cartilage degeneration that occurs in osteoarthritis. Not only does this approach require anatomically sized and functional engineered cartilage, but the inflammatory environment within an arthritic joint may also inhibit chondrogenesis and induce degradation of native and engineered cartilage. The goal of this study was to use adult stem cells to engineer anatomically shaped, functional cartilage constructs capable of tunable and inducible expression of antiinflammatory molecules, specifically IL-1 receptor antagonist (IL-1Ra). Large (22-mm-diameter) hemispherical scaffolds were fabricated from 3D woven poly(ε-caprolactone) (PCL) fibers into two different configurations and seeded with human adipose-derived stem cells (ASCs). Doxycycline (dox)-inducible lentiviral vectors containing eGFP or IL-1Ra transgenes were immobilized to the PCL to transduce ASCs upon seeding, and constructs were cultured in chondrogenic conditions for 28 d. Constructs showed biomimetic cartilage properties and uniform tissue growth while maintaining their anatomic shape throughout culture. IL-1Ra–expressing constructs produced nearly 1 µg/mL of IL-1Ra upon controlled induction with dox. Treatment with IL-1 significantly increased matrix metalloprotease activity in the conditioned media of eGFP-expressing constructs but not in IL-1Ra–expressing constructs. Our findings show that advanced textile manufacturing combined with scaffold-mediated gene delivery can be used to tissue engineer large anatomically shaped cartilage constructs that possess controlled delivery of anticytokine therapy. Importantly, these cartilage constructs have the potential to provide mechanical functionality immediately upon implantation, as they will need to replace a majority, if not the entire joint surface to restore function. PMID:27432980

Raman fiberoptic probe for monitoring human tissue engineered oral mucosa constructs

NASA Astrophysics Data System (ADS)

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.

Center for Space Construction

NASA Technical Reports Server (NTRS)

Su, Renjeng

1998-01-01

The Center for Space Construction (CSC) at University of Colorado at Boulder is one of eight University Space Engineering Research Centers established by NASA in 1988. The mission of the Center is to conduct research into space technology and to directly contribute to space engineering education. The Center reports to the Department of Aerospace Engineering Sciences and resides in the College of Engineering and Applied Sciences. The College has a long and successful track record of cultivating multi-disciplinary research and education programs. The Center for Space Construction represents prominent evidence of this record. The basic concept on which the Center was founded is the in-space construction of large space systems, such as space stations, interplanetary space vehicles, and extraterrestrial space structures. Since 1993, the scope of CSC research has evolved to include the design and construction of all spacecraft, large and small. With the broadened scope our research projects seek to impact the technological basis for spacecraft such as remote sensing satellites, communication satellites and other special-purpose spacecraft, as well as large space platforms. A summary of accomplishments, including student participation and degrees awarded, during the contract period is presented.

Value engineering awareness study for sustainable construction in Malaysia

NASA Astrophysics Data System (ADS)

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.

Combined chemical and structural signals of biomaterials synergistically activate cell-cell communications for improving tissue regeneration.

PubMed

Xu, Yachen; Peng, Jinliang; Dong, Xin; Xu, Yuhong; Li, Haiyan; Chang, Jiang

2017-06-01

Biomaterials are only used as carriers of cells in the conventional tissue engineering. Considering the multi-cell environment and active cell-biomaterial interactions in tissue regeneration process, in this study, structural signals of aligned electrospun nanofibers and chemical signals of bioglass (BG) ionic products in cell culture medium are simultaneously applied to activate fibroblast-endothelial co-cultured cells in order to obtain an improved skin tissue engineering construct. Results demonstrate that the combined biomaterial signals synergistically activate fibroblast-endothelial co-culture skin tissue engineering constructs through promotion of paracrine effects and stimulation of gap junctional communication between cells, which results in enhanced vascularization and extracellular matrix protein synthesis in the constructs. Structural signals of aligned electrospun nanofibers play an important role in stimulating both of paracrine and gap junctional communication while chemical signals of BG ionic products mainly enhance paracrine effects. In vivo experiments reveal that the activated skin tissue engineering constructs significantly enhance wound healing as compared to control. This study indicates the advantages of synergistic effects between different bioactive signals of biomaterials can be taken to activate communication between different types of cells for obtaining tissue engineering constructs with improved functions. Tissue engineering can regenerate or replace tissue or organs through combining cells, biomaterials and growth factors. Normally, for repairing a specific tissue, only one type of cells, one kind of biomaterials, and specific growth factors are used to support cell growth. In this study, we proposed a novel tissue engineering approach by simply using co-cultured cells and combined biomaterial signals. Using a skin tissue engineering model, we successfully proved that the combined biomaterial signals such as surface nanostructures and bioactive ions could synergistically stimulate the cell-cell communication in co-culture system through paracrine effects and gap junction activation, and regulated expression of growth factors and extracellular matrix proteins, resulting in an activated tissue engineering constructs that significantly enhanced skin regeneration. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

48 CFR 36.102 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS General 36.102 Definitions. As used in this part— Contract is intended to refer to a contract for construction or a contract for architect-engineer services..., structural, electrical, mechanical, and fire protection), producing the technical specifications and drawings...

48 CFR 36.102 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS General 36.102 Definitions. As used in this part— Contract is intended to refer to a contract for construction or a contract for architect-engineer services..., structural, electrical, mechanical, and fire protection), producing the technical specifications and drawings...

48 CFR 36.102 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS General 36.102 Definitions. As used in this part— Contract is intended to refer to a contract for construction or a contract for architect-engineer services..., structural, electrical, mechanical, and fire protection), producing the technical specifications and drawings...

48 CFR 36.102 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS General 36.102 Definitions. As used in this part— Contract is intended to refer to a contract for construction or a contract for architect-engineer services..., structural, electrical, mechanical, and fire protection), producing the technical specifications and drawings...

48 CFR 36.102 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS General 36.102 Definitions. As used in this part— Contract is intended to refer to a contract for construction or a contract for architect-engineer services..., structural, electrical, mechanical, and fire protection), producing the technical specifications and drawings...

76 FR 35424 - Information Collection Requirements; Defense Federal Acquisition Regulation Supplement...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-17

... DEPARTMENT OF DEFENSE Defense Acquisition Regulations System Information Collection Requirements; Defense Federal Acquisition Regulation Supplement; Construction and Architect-Engineer Contracts AGENCY..., Construction and Architect-Engineer Contracts, and Related Clauses at DFARS 252.236; OMB Control Number 0704...

Imaging Strategies for Tissue Engineering Applications

PubMed Central

Nam, Seung Yun; Ricles, Laura M.; Suggs, Laura J.

2015-01-01

Tissue engineering has evolved with multifaceted research being conducted using advanced technologies, and it is progressing toward clinical applications. As tissue engineering technology significantly advances, it proceeds toward increasing sophistication, including nanoscale strategies for material construction and synergetic methods for combining with cells, growth factors, or other macromolecules. Therefore, to assess advanced tissue-engineered constructs, tissue engineers need versatile imaging methods capable of monitoring not only morphological but also functional and molecular information. However, there is no single imaging modality that is suitable for all tissue-engineered constructs. Each imaging method has its own range of applications and provides information based on the specific properties of the imaging technique. Therefore, according to the requirements of the tissue engineering studies, the most appropriate tool should be selected among a variety of imaging modalities. The goal of this review article is to describe available biomedical imaging methods to assess tissue engineering applications and to provide tissue engineers with criteria and insights for determining the best imaging strategies. Commonly used biomedical imaging modalities, including X-ray and computed tomography, positron emission tomography and single photon emission computed tomography, magnetic resonance imaging, ultrasound imaging, optical imaging, and emerging techniques and multimodal imaging, will be discussed, focusing on the latest trends of their applications in recent tissue engineering studies. PMID:25012069

Towards organ printing: engineering an intra-organ branched vascular tree

PubMed Central

Visconti, Richard P; Kasyanov, Vladimir; Gentile, Carmine; Zhang, Jing; Markwald, Roger R; Mironov, Vladimir

2013-01-01

Importance of the field Effective vascularization of thick three-dimensional engineered tissue constructs is a problem in tissue engineering. As in native organs, a tissue-engineered intra-organ vascular tree must be comprised of a network of hierarchically branched vascular segments. Despite this requirement, current tissue-engineering efforts are still focused predominantly on engineering either large-diameter macrovessels or microvascular networks. Areas covered in this review We present the emerging concept of organ printing or robotic additive biofabrication of an intra-organ branched vascular tree, based on the ability of vascular tissue spheroids to undergo self-assembly. What the reader will gain The feasibility and challenges of this robotic biofabrication approach to intra-organ vascularization for tissue engineering based on organ-printing technology using self-assembling vascular tissue spheroids including clinically relevantly vascular cell sources are analyzed. Take home message It is not possible to engineer 3D thick tissue or organ constructs without effective vascularization. An effective intra-organ vascular system cannot be built by the simple connection of large-diameter vessels and microvessels. Successful engineering of functional human organs suitable for surgical implantation will require concomitant engineering of a ‘built in’ intra-organ branched vascular system. Organ printing enables biofabrication of human organ constructs with a ‘built in’ intra-organ branched vascular tree. PMID:20132061

Airfield construction (3rd revised and enlarged edition)

NASA Astrophysics Data System (ADS)

Goretskii, Leonid I.; Boguslavskii, Adol'f. M.; Serebrenikov, Vadim A.; Barzdo, V. I.; Leshchitskaia, T. P.; Polosin-Nikitin, S. M.

The principal engineering aspects of airfield construction are discussed. In particular, attention is given to the fundamental principles and organizational aspects of airfield construction; excavation work and airfield layout; construction of drainage systems; foundations and pavements; and quality control and safety engineering. The discussion also covers the operation of various support plants, including concrete production and mixing, production of asphalt-concrete mixtures and organic binders, production of structural steel and reinforced concrete components, and operation of stone quarries and gravel pits.

A STUDY ON THE APPLICATION OF VALUE ENGINEERING TO THE CONSTRUCTION INDUSTRY

NASA Astrophysics Data System (ADS)

Kemmochi, Sampei; Koizumi, Atsushi

Value Engineering (VE), one of the effective management techniques to provide products and services, is focused as a measure to reduce the cost on public works, but its effectiveness as a management technique doesn't seem to be fully understood in the construction industry. This paper demonstrates aspects and issues of VE in construction industry by comparing with manufacturing industry, and to combat these, VE which is implemented in construction industry must be succinct and proposes methods to conduct it from the viewpoint of construction industry. At last, the place to go to for construction industry down the road regarding the VE adaptation is clarified.

The experimental study of genetic engineering human neural stem cells mediated by lentivirus to express multigene.

PubMed

Cai, Pei-qiang; Tang, Xun; Lin, Yue-qiu; Martin, Oudega; Sun, Guang-yun; Xu, Lin; Yang, Yun-kang; Zhou, Tian-hua

2006-02-01

To explore the feasibility to construct genetic engineering human neural stem cells (hNSCs) mediated by lentivirus to express multigene in order to provide a graft source for further studies of spinal cord injury (SCI). Human neural stem cells from the brain cortex of human abortus were isolated and cultured, then gene was modified by lentivirus to express both green fluorescence protein (GFP) and rat neurotrophin-3 (NT-3); the transgenic expression was detected by the methods of fluorescence microscope, dorsal root ganglion of fetal rats and slot blot. Genetic engineering hNSCs were successfully constructed. All of the genetic engineering hNSCs which expressed bright green fluorescence were observed under the fluorescence microscope. The conditioned medium of transgenic hNSCs could induce neurite flourishing outgrowth from dorsal root ganglion (DRG). The genetic engineering hNSCs expressed high level NT-3 which could be detected by using slot blot. Genetic engineering hNSCs mediated by lentivirus can be constructed to express multigene successfully.

Using Project Management Systems at the Construction Field Office

DTIC Science & Technology

1989-03-01

instrumentation 13550 transportation control instrumentation 13600 solor energy systems 13700 wind energy systems 13800 building automation systems ...Engineering Research Laboratory AD-A207 077 Using Project Management Systems at the Construction Field Office by E. William East Jeffrey G. Kirby Automated...automated systems available, engineers at the construction fieid office (or resident office) are faced with the over- whelming task of choosing which

Flood trends and river engineering on the Mississippi River system

USGS Publications Warehouse

Pinter, N.; Jemberie, A.A.; Remo, J.W.F.; Heine, R.A.; Ickes, B.S.

2008-01-01

Along >4000 km of the Mississippi River system, we document that climate, land-use change, and river engineering have contributed to statistically significant increases in flooding over the past 100-150 years. Trends were tested using a database of >8 million hydrological measurements. A geospatial database of historical engineering construction was used to quantify the response of flood levels to each unit of engineering infrastructure. Significant climate- and/or land use-driven increases in flow were detected, but the largest and most pervasive contributors to increased flooding on the Mississippi River system were wing dikes and related navigational structures, followed by progressive levee construction. In the area of the 2008 Upper Mississippi flood, for example, about 2 m of the flood crest is linked to navigational and flood-control engineering. Systemwide, large increases in flood levels were documented at locations and at times of wing-dike and levee construction. Copyright 2008 by the American Geophysical Union.

Fabrication of a Neotrachea Using Engineered Cartilage

PubMed Central

Weidenbecher, Mark; Tucker, Harvey M.; Awadallah, Amad; Dennis, James E.

2008-01-01

Objectives Surgical management of long-segment tracheal stenosis is an ongoing problem. Many types of tracheal prostheses have been tried but with limited success because of immune rejection, graft ischemia, or restenosis. Tissue engineered cartilage may offer a solution to this problem, although scaffolds, which are currently often used for support, can lead to biocompatibility problems. This study investigated the feasibility of scaffold-free cartilage to tissue engineer a vascularized neotrachea in rabbits. Study Design Animal study. Methods Autologous neotracheal constructs were implanted in the abdomen of six New Zealand white rabbits. Auricular chondrocytes were used to engineer scaffold-free cartilage sheets. A muscle flap raised from the external abdominal oblique muscle and the engineered cartilage were wrapped around a silicone stent to fabricate a vascularized neotrachea in vivo. In two of the six rabbits, a full thickness skin graft was used to create an epithelial lining. The constructs were harvested after either 6 or 10 weeks. Results All neotracheal constructs were healthy with well-vascularized and integrated layers. The implanted engineered cartilage underwent a remodeling process, forming a solid tracheal framework. Constructs harvested after 10 weeks proved to have significantly better mechanical properties than after 6 weeks and were comparable with the rabbit's native trachea. Conclusion Scaffold-free engineered cartilage can successfully fabricate a well-vascularized, autologous neotrachea with excellent mechanical properties. The results suggest that this approach can be used to reconstruct tracheal defects in rabbits. PMID:18197138

Reconstruction of structure and function in tissue engineering of solid organs: Toward simulation of natural development based on decellularization.

PubMed

Zheng, Chen-Xi; Sui, Bing-Dong; Hu, Cheng-Hu; Qiu, Xin-Yu; Zhao, Pan; Jin, Yan

2018-04-27

Failure of solid organs, such as the heart, liver, and kidney, remains a major cause of the world's mortality due to critical shortage of donor organs. Tissue engineering, which uses elements including cells, scaffolds, and growth factors to fabricate functional organs in vitro, is a promising strategy to mitigate the scarcity of transplantable organs. Within recent years, different construction strategies that guide the combination of tissue engineering elements have been applied in solid organ tissue engineering and have achieved much progress. Most attractively, construction strategy based on whole-organ decellularization has become a popular and promising approach, because the overall structure of extracellular matrix can be well preserved. However, despite the preservation of whole structure, the current constructs derived from decellularization-based strategy still perform partial functions of solid organs, due to several challenges, including preservation of functional extracellular matrix structure, implementation of functional recellularization, formation of functional vascular network, and realization of long-term functional integration. This review overviews the status quo of solid organ tissue engineering, including both advances and challenges. We have also put forward a few techniques with potential to solve the challenges, mainly focusing on decellularization-based construction strategy. We propose that the primary concept for constructing tissue-engineered solid organs is fabricating functional organs based on intact structure via simulating the natural development and regeneration processes. Copyright © 2018 John Wiley & Sons, Ltd.

Predicting on-site environmental impacts of municipal engineering works

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

Gangolells, Marta, E-mail: marta.gangolells@upc.edu; Casals, Miquel, E-mail: miquel.casals@upc.edu; Forcada, Núria, E-mail: nuria.forcada@upc.edu

2014-01-15

The research findings fill a gap in the body of knowledge by presenting an effective way to evaluate the significance of on-site environmental impacts of municipal engineering works prior to the construction stage. First, 42 on-site environmental impacts of municipal engineering works were identified by means of a process-oriented approach. Then, 46 indicators and their corresponding significance limits were determined on the basis of a statistical analysis of 25 new-build and remodelling municipal engineering projects. In order to ensure the objectivity of the assessment process, direct and indirect indicators were always based on quantitative data from the municipal engineering projectmore » documents. Finally, two case studies were analysed and found to illustrate the practical use of the proposed model. The model highlights the significant environmental impacts of a particular municipal engineering project prior to the construction stage. Consequently, preventive actions can be planned and implemented during on-site activities. The results of the model also allow a comparison of proposed municipal engineering projects and alternatives with respect to the overall on-site environmental impact and the absolute importance of a particular environmental aspect. These findings are useful within the framework of the environmental impact assessment process, as they help to improve the identification and evaluation of on-site environmental aspects of municipal engineering works. The findings may also be of use to construction companies that are willing to implement an environmental management system or simply wish to improve on-site environmental performance in municipal engineering projects. -- Highlights: • We present a model to predict the environmental impacts of municipal engineering works. • It highlights significant on-site environmental impacts prior to the construction stage. • Findings are useful within the environmental impact assessment process. • They also help contractors to implement environmental management systems.« less

Presentation on systems cluster research

NASA Technical Reports Server (NTRS)

Morgenthaler, George W.

1989-01-01

This viewgraph presentation presents an overview of systems cluster research performed by the Center for Space Construction. The goals of the research are to develop concepts, insights, and models for space construction and to develop systems engineering/analysis curricula for training future aerospace engineers. The following topics are covered: CSC systems analysis/systems engineering (SIMCON) model, CSC systems cluster schedule, system life-cycle, model optimization techniques, publications, cooperative efforts, and sponsored research.

Novel imaging analysis system to measure the spatial dimension of engineered tissue construct.

PubMed

Choi, Kyoung-Hwan; Yoo, Byung-Su; Park, So Ra; Choi, Byung Hyune; Min, Byoung-Hyun

2010-02-01

The measurement of the spatial dimensions of tissue-engineered constructs is very important for their clinical applications. In this study, a novel method to measure the volume of tissue-engineered constructs was developed using iterative mathematical computations. The method measures and analyzes three-dimensional (3D) parameters of a construct to estimate its actual volume using a sequence of software-based mathematical algorithms. The mathematical algorithm is composed of two stages: the shape extraction and the determination of volume. The shape extraction utilized 3D images of a construct: length, width, and thickness, captured by a high-quality camera with charge coupled device. The surface of the 3D images was then divided into fine sections. The area of each section was measured and combined to obtain the total surface area. The 3D volume of the target construct was then mathematically obtained using its total surface area and thickness. The accuracy of the measurement method was verified by comparing the results with those obtained from the hydrostatic weighing method (Korea Research Institute of Standards and Science [KRISS], Korea). The mean difference in volume between two methods was 0.0313 +/- 0.0003% (n = 5, P = 0.523) with no significant statistical difference. In conclusion, our image-based spatial measurement system is a reliable and easy method to obtain an accurate 3D volume of a tissue-engineered construct.

NEARING THE END OF CONSTRUCTION ON THE LOX TEST STAND AT MSFC.

NASA Image and Video Library

2015-01-08

AS THE END OF CONSTRUCTION ON TEST STAND 4697, THE LIQUID OXYGEN TANK TEST STAND AT MARSHALL SPACE FLIGHT CENTER, PROJECT ENGINEERS PHIL HENDRIX, FROM MSFC, AND CURTNEY WALTERS FROM THE U.S. CORP OF ENGINEERS, STUDY PLANS AND PROGRESS.

23 CFR 660.117 - Funding, records and accounting.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS... be required. (b) Funds for FHs may be used for: (1) Planning; (2) Federal Lands Highway research; (3) Preliminary and construction engineering; and (4) Construction. (c) Funds for FHs may be made available for...

Induction of functional tissue-engineered skeletal muscle constructs by defined electrical stimulation.

PubMed

Ito, Akira; Yamamoto, Yasunori; Sato, Masanori; Ikeda, Kazushi; Yamamoto, Masahiro; Fujita, Hideaki; Nagamori, Eiji; Kawabe, Yoshinori; Kamihira, Masamichi

2014-04-24

Electrical impulses are necessary for proper in vivo skeletal muscle development. To fabricate functional skeletal muscle tissues in vitro, recapitulation of the in vivo niche, including physical stimuli, is crucial. Here, we report a technique to engineer skeletal muscle tissues in vitro by electrical pulse stimulation (EPS). Electrically excitable tissue-engineered skeletal muscle constructs were stimulated with continuous electrical pulses of 0.3 V/mm amplitude, 4 ms width, and 1 Hz frequency, resulting in a 4.5-fold increase in force at day 14. In myogenic differentiation culture, the percentage of peak twitch force (%Pt) was determined as the load on the tissue constructs during the artificial exercise induced by continuous EPS. We optimized the stimulation protocol, wherein the tissues were first subjected to 24.5%Pt, which was increased to 50-60%Pt as the tissues developed. This technique may be a useful approach to fabricate tissue-engineered functional skeletal muscle constructs.

Plant nitrogen regulatory P-PII polypeptides

DOEpatents

Coruzzi, Gloria M.; Lam, Hon-Ming; Hsieh, Ming-Hsiun

2004-11-23

The present invention generally relates to plant nitrogen regulatory PII gene (hereinafter P-PII gene), a gene involved in regulating plant nitrogen metabolism. The invention provides P-PII nucleotide sequences, expression constructs comprising said nucleotide sequences, and host cells and plants having said constructs and, optionally expressing the P-PII gene from said constructs. The invention also provides substantially pure P-PII proteins. The P-PII nucleotide sequences and constructs of the invention may be used to engineer organisms to overexpress wild-type or mutant P-PII regulatory protein. Engineered plants that overexpress or underexpress P-PII regulatory protein may have increased nitrogen assimilation capacity. Engineered organisms may be used to produce P-PII proteins which, in turn, can be used for a variety of purposes including in vitro screening of herbicides. P-PII nucleotide sequences have additional uses as probes for isolating additional genomic clones having the promoters of P-PII gene. P-PII promoters are light- and/or sucrose-inducible and may be advantageously used in genetic engineering of plants.

48 CFR 1536.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 1536.602 Section 1536.602 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1536.602 Selection of firms for architect-engineer contracts. ...

48 CFR 636.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 636.602 Section 636.602 Federal Acquisition Regulations System DEPARTMENT OF STATE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 636.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1536.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 1536.602 Section 1536.602 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1536.602 Selection of firms for architect-engineer contracts. ...

48 CFR 2936.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 2936.602 Section 2936.602 Federal Acquisition Regulations System DEPARTMENT OF LABOR GENERAL CONTRACTING REQUIREMENTS CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 2936.602 Selection of firms for architect-engineer contracts. ...

48 CFR 436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 436.602 Section 436.602 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Service 436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1336.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 1336.602 Section 1336.602 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1336.602 Selection of firms for architect-engineer contracts. ...

48 CFR 636.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 636.602 Section 636.602 Federal Acquisition Regulations System DEPARTMENT OF STATE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 636.602 Selection of firms for architect-engineer contracts. ...

48 CFR 536.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 536.602 Section 536.602 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 536.602 Selection of firms for architect-engineer contracts. ...

48 CFR 36.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 36.602 Section 36.602 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.602 Selection of firms for architect-engineer contracts. ...

48 CFR 536.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 536.602 Section 536.602 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 536.602 Selection of firms for architect-engineer contracts. ...

48 CFR 636.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 636.602 Section 636.602 Federal Acquisition Regulations System DEPARTMENT OF STATE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 636.602 Selection of firms for architect-engineer contracts. ...

48 CFR 36.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 36.602 Section 36.602 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.602 Selection of firms for architect-engineer contracts. ...

48 CFR 2936.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 2936.602 Section 2936.602 Federal Acquisition Regulations System DEPARTMENT OF LABOR GENERAL CONTRACTING REQUIREMENTS CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 2936.602 Selection of firms for architect-engineer contracts. ...

48 CFR 36.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 36.602 Section 36.602 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.602 Selection of firms for architect-engineer contracts. ...

48 CFR 36.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 36.602 Section 36.602 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1536.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 1536.602 Section 1536.602 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1536.602 Selection of firms for architect-engineer contracts. ...

48 CFR 2936.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 2936.602 Section 2936.602 Federal Acquisition Regulations System DEPARTMENT OF LABOR GENERAL CONTRACTING REQUIREMENTS CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 2936.602 Selection of firms for architect-engineer contracts. ...

48 CFR 536.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 536.602 Section 536.602 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 536.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1336.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 1336.602 Section 1336.602 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1336.602 Selection of firms for architect-engineer contracts. ...

48 CFR 436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 436.602 Section 436.602 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Service 436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 536.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 536.602 Section 536.602 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 536.602 Selection of firms for architect-engineer contracts. ...

48 CFR 2936.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 2936.602 Section 2936.602 Federal Acquisition Regulations System DEPARTMENT OF LABOR GENERAL CONTRACTING REQUIREMENTS CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 2936.602 Selection of firms for architect-engineer contracts. ...

48 CFR 36.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 36.602 Section 36.602 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.602 Selection of firms for architect-engineer contracts. ...

48 CFR 436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 436.602 Section 436.602 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Service 436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1336.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 1336.602 Section 1336.602 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1336.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1536.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 1536.602 Section 1536.602 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1536.602 Selection of firms for architect-engineer contracts. ...

48 CFR 2936.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 2936.602 Section 2936.602 Federal Acquisition Regulations System DEPARTMENT OF LABOR GENERAL CONTRACTING REQUIREMENTS CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 2936.602 Selection of firms for architect-engineer contracts. ...

48 CFR 636.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 636.602 Section 636.602 Federal Acquisition Regulations System DEPARTMENT OF STATE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 636.602 Selection of firms for architect-engineer contracts. ...

48 CFR 436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 436.602 Section 436.602 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Service 436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1536.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 1536.602 Section 1536.602 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1536.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1336.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 1336.602 Section 1336.602 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1336.602 Selection of firms for architect-engineer contracts. ...

48 CFR 436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 436.602 Section 436.602 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Service 436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1336.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 1336.602 Section 1336.602 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1336.602 Selection of firms for architect-engineer contracts. ...

48 CFR 536.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 536.602 Section 536.602 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 536.602 Selection of firms for architect-engineer contracts. ...

48 CFR 636.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 636.602 Section 636.602 Federal Acquisition Regulations System DEPARTMENT OF STATE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 636.602 Selection of firms for architect-engineer contracts. ...

Engineering Microvascularized 3D Tissue Using Alginate-Chitosan Microcapsules.

PubMed

Zhang, Wujie; Choi, Jung K; He, Xiaoming

2017-02-01

Construction of vascularized tissues is one of the major challenges of tissue engineering. The goal of this study was to engineer 3D microvascular tissues by incorporating the HUVEC-CS cells with a collagen/alginate-chitosan (AC) microcapsule scaffold. In the presence of AC microcapsules, a 3D vascular-like network was clearly observable. The results indicated the importance of AC microcapsules in engineering microvascular tissues -- providing support and guiding alignment of HUVEC-CS cells. This approach provides an alternative and promising method for constructing vascularized tissues.

Details of the Construction and Production of Fuel Pumps and Fuel Nozzles for the Airplane Diesel Engine

NASA Technical Reports Server (NTRS)

Lubenetsky, W S

1936-01-01

This report presents investigations into the design and construction of fuel pumps for diesel engines. The results of the pump tests on the engines showed that, with a good cut-off, accurate injection, assured by the proper adjustment of the pump elements, there is a decrease in the consumption of fuel and hence an increase in the rated power of the engine. Some of the aspects investigated include: cam profile, coefficient of discharge, and characteristics of the injection system.

Hydrogel Bioprinted Microchannel Networks for Vascularization of Tissue Engineering Constructs

PubMed Central

Bertassoni, Luiz E.; Cecconi, Martina; Manoharan, Vijayan; Nikkhah, Mehdi; Hjortnaes, Jesper; Cristino, Ana Luiza; Barabaschi, Giada; Demarchi, Danilo; Dokmeci, Mehmet R.; Yang, Yunzhi; Khademhosseini, Ali

2014-01-01

Vascularization remains a critical challenge in tissue engineering. The development of vascular networks within densely populated and metabolically functional tissues facilitate transport of nutrients and removal of waste products, thus preserving cellular viability over a long period of time. Despite tremendous progress in fabricating complex tissue constructs in the past few years, approaches for controlled vascularization within hydrogel based engineered tissue constructs have remained limited. Here, we report a three dimensional (3D) micromolding technique utilizing bioprinted agarose template fibers to fabricate microchannel networks with various architectural features within photo cross linkable hydrogel constructs. Using the proposed approach, we were able to successfully embed functional and perfusable microchannels inside methacrylated gelatin (GelMA), star poly (ethylene glycol-co-lactide) acrylate (SPELA), poly (ethylene glycol) dimethacrylate (PEGDMA) and poly (ethylene glycol) diacrylate (PEGDA) hydrogels at different concentrations. In particular, GelMA hydrogels were used as a model to demonstrate the functionality of the fabricated vascular networks in improving mass transport, cellular viability and differentiation within the cell-laden tissue constructs. In addition, successful formation of endothelial monolayers within the fabricated channels was confirmed. Overall, our proposed strategy represents an effective technique for vascularization of hydrogel constructs with useful applications in tissue engineering and organs on a chip. PMID:24860845

APPLICATION OF THE 3D MODEL OF RAILWAY VIADUCTS TO COST ESTIMATION AND CONSTRUCTION

NASA Astrophysics Data System (ADS)

Fujisawa, Yasuo; Yabuki, Nobuyoshi; Igarashi, Zenichi; Yoshino, Hiroyuki

Three dimensional models of civil engineering structures are only partially used in either design or construction but not both. Research on integration of design, cost estimation and construction by 3Dmodels has not been heard in civil engineering domain yet. Using continuously a 3D product model of a structure from design to construction through estimation should improve the efficiency and decrease the occurrence of mistakes, hence enhancing the quality. In this research, we investigated the current practices of flow from design to construction, particularly focusing on cost estimation. Then, we identified advantages and issues on utilization of 3D design models to estimation and construction by applying 3D models to an actual railway construction project.

Industrial Education. "Small Engines".

ERIC Educational Resources Information Center

Parma City School District, OH.

Part of a series of curriculum guides dealing with industrial education in junior high schools, this guide provides the student with information and manipulative experiences on small gasoline engines. Included are sections on shop adjustment, safety, small engines, internal combustion, engine construction, four stroke engines, two stroke engines,…

Growth Factor Stimulation Improves the Structure and Properties of Scaffold-Free Engineered Auricular Cartilage Constructs

PubMed Central

Rosa, Renata G.; Joazeiro, Paulo P.; Bianco, Juares; Kunz, Manuela; Weber, Joanna F.; Waldman, Stephen D.

2014-01-01

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. PMID:25126941

Conceptional Considerations to Energy Balance and Global Warming Potential of Soil Bioengineering Structures

NASA Astrophysics Data System (ADS)

von der Thannen, Magdalena; Paratscha, Roman; Smutny, Roman; Lampalzer, Thomas; Strauss, Alfred; Rauch, Hans Peter

2016-04-01

Nowadays there is a high demand on engineering solutions considering not only technical aspects but also ecological and aesthetic values. In this context soil bioengineering techniques are often used as standalone solutions or in combination with conventional engineering structures. It is a construction technique that uses biological components for hydraulic and civil engineering solutions. In general it pursues the same objectives as conventional civil engineering structures. Currently the used assessment methods for soil bioengineering structures are referencing technically, ecologically and socio-economically. In a modern engineering approach additionally, environmental impacts and potential added values should be considered. The research project E-Protect aims at developing Environmental Life Cycle Assessment (LCA) models for this special field of alpine protective constructions. Both, the Cumulative Energy Demand (CED) and the Global Warming Potential (GWP) should be considered in an Environmental LCA over the whole life cycle of an engineering structure. The life cycle itself can be divided into three phases: the construction phase, the use phase and the end of life phase. The paper represents a concept to apply an Environmental LCA model for soil bioengineering structures. Beside the construction phase of these structures particular attention will be given to the use phase. It is not only important in terms of engineering effects but also plays an important role for positive carbon footprint due to the growing plants of soil bioengineering structures in contrast to conventional structures. Innovative Environmental LCA models will be applied to soil bioengineering structures which provide a new transparency for the responsible planners and stakeholders, by pointing out the total consumption of resources in all construction phases and components.

Possibility of reducing CO2 emissions from internal combustion engines

NASA Astrophysics Data System (ADS)

Drabik, Dawid; Mamala, Jarosław; Śmieja, Michał; Prażnowski, Krzysztof

2017-10-01

Article defines on the possibility of reduction CO2 of the internal combustion engine and presents the analysis based on originally conducted studies. The increase in overall engine efficiency is sought after by all engineers dealing with engine construction, one of the major ways to reduce CO2 emissions is to increase the compression ratio. The application of the compression ratio that has been increased constructional in the engine will, on one hand, bring about the increase in the theoretical efficiency, but, on the other hand, require a system for pressure control at a higher engine load in order to prevent engine knocking. For the purposes of the article there was carried out a number of studies and compiled results, and on their basis determined what have a major impact on the reducing CO2.

Design type air engine Di Pietro

NASA Astrophysics Data System (ADS)

Zwierzchowski, Jaroslaw

The article presents a pneumatic engine constructed by Angelo Di Pietro. 3D solid models of pneumatic engine components were presented therein. A directional valve is a key element of the control system. The valve functions as a camshaft distributing air to particular engine chambers. The construction designed by Angelo Di Pietro is modern and innovative. A pneumatic engine requires low pressure to start rotary movement. With the use of CFD software, the fields of velocity vectors' distribution were determined. Moreover, the author determined the distribution of pressure values in engine inlet and outlet channels. CFD model studies on engine operation were conducted for chosen stages of operating cycles. On the basis of simulation tests that were conducted, the values of flow rates for the engine were determined. The distribution of pressure values made it possible to evaluate the torque value on the rotating shaft.

On civil engineering disasters and their mitigation

NASA Astrophysics Data System (ADS)

Xie, Lili; Qu, Zhe

2018-01-01

Civil engineering works such as buildings and infrastructure are the carriers of human civilization. They are, however, also the origins of various types of disasters, which are referred to in this paper as civil engineering disasters. This paper presents the concept of civil engineering disasters, their characteristics, classification, causes, and mitigation technologies. Civil engineering disasters are caused primarily by civil engineering defects, which are usually attributed to improper selection of construction site, hazard assessment, design and construction, occupancy, and maintenance. From this viewpoint, many so-called natural disasters such as earthquakes, strong winds, floods, landslides, and debris flows are substantially due to civil engineering defects rather than the actual natural hazards. Civil engineering disasters occur frequently and globally and are the most closely related to human beings among all disasters. This paper emphasizes that such disasters can be mitigated mainly through civil engineering measures, and outlines the related objectives and scientific and technological challenges.

Practicing Engineering While Building with Blocks: Identifying Engineering Thinking

ERIC Educational Resources Information Center

Bagiati, Aikaterini; Evangelou, Demetra

2016-01-01

Children's free play naturally enhances skills of observation, communication, experimentation, as well as development of rationale and construction skills. These domains, while synthesised, can lead to the development of certain process models regarding the way constructions could be designed, built and improved. The Design Process model…

Try This: Construct a Water Catchment

ERIC Educational Resources Information Center

Teaching Science, 2017

2017-01-01

EngQuest, an initiative of Engineers Australia, provides an exciting, non-competitive way for students to participate in free, fun and educational engineering activities involving mathematics, science and technology. This article describes a project designed to teach middle school students how to construct a water catchment system. Water…

14 CFR 33.34 - Turbocharger rotors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turbocharger rotors. 33.34 Section 33.34... STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.34 Turbocharger rotors. Each turbocharger case must be designed and constructed to be able to contain fragments of a...

14 CFR 33.34 - Turbocharger rotors.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Turbocharger rotors. 33.34 Section 33.34... STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.34 Turbocharger rotors. Each turbocharger case must be designed and constructed to be able to contain fragments of a...

14 CFR 33.34 - Turbocharger rotors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Turbocharger rotors. 33.34 Section 33.34... STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.34 Turbocharger rotors. Each turbocharger case must be designed and constructed to be able to contain fragments of a...

14 CFR 33.34 - Turbocharger rotors.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Turbocharger rotors. 33.34 Section 33.34... STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.34 Turbocharger rotors. Each turbocharger case must be designed and constructed to be able to contain fragments of a...

14 CFR 33.34 - Turbocharger rotors.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Turbocharger rotors. 33.34 Section 33.34... STANDARDS: AIRCRAFT ENGINES Design and Construction; Reciprocating Aircraft Engines § 33.34 Turbocharger rotors. Each turbocharger case must be designed and constructed to be able to contain fragments of a...

29 CFR 1926.758 - Systems-engineered metal buildings.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.758... systems-engineered metal buildings except §§ 1926.755 (column anchorage) and 1926.757 (open web steel... hoisting equipment is released. (d) Construction loads shall not be placed on any structural steel...

29 CFR 1926.758 - Systems-engineered metal buildings.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.758... systems-engineered metal buildings except §§ 1926.755 (column anchorage) and 1926.757 (open web steel... hoisting equipment is released. (d) Construction loads shall not be placed on any structural steel...

29 CFR 1926.758 - Systems-engineered metal buildings.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.758... systems-engineered metal buildings except §§ 1926.755 (column anchorage) and 1926.757 (open web steel... hoisting equipment is released. (d) Construction loads shall not be placed on any structural steel...

48 CFR 1836.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 1836.602 Section 1836.602 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1836.602 Selection of firms for architect-engineer contracts. ...

48 CFR 836.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 836.602 Section 836.602 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1836.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 1836.602 Section 1836.602 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1836.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 1436.602 Section 1436.602 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 1436.602 Section 1436.602 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 836.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 836.602 Section 836.602 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 1436.602 Section 1436.602 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1836.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 1836.602 Section 1836.602 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1836.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1836.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 1836.602 Section 1836.602 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1836.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 1436.602 Section 1436.602 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1836.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 1836.602 Section 1836.602 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1836.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 1436.602 Section 1436.602 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 836.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 836.602 Section 836.602 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602 Selection of firms for architect-engineer contracts. ...

48 CFR 836.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 836.602 Section 836.602 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602 Selection of firms for architect-engineer contracts. ...

48 CFR 836.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 836.602 Section 836.602 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602 Selection of firms for architect-engineer contracts. ...

Biomimetic and synthetic esophageal tissue engineering.

PubMed

Jensen, Todd; Blanchette, Alex; Vadasz, Stephanie; Dave, Apeksha; Canfarotta, Michael; Sayej, Wael N; Finck, Christine

2015-07-01

A tissue-engineered esophagus offers an alternative for the treatment of pediatric patients suffering from severe esophageal malformations, caustic injury, and cancer. Additionally, adult patients suffering from carcinoma or trauma would benefit. Donor rat esophageal tissue was physically and enzymatically digested to isolate epithelial and smooth muscle cells, which were cultured in epithelial cell medium or smooth muscle cell medium and characterized by immunofluorescence. Isolated cells were also seeded onto electrospun synthetic PLGA and PCL/PLGA scaffolds in a physiologic hollow organ bioreactor. After 2 weeks of in vitro culture, tissue-engineered constructs were orthotopically transplanted. Isolated cells were shown to give rise to epithelial, smooth muscle, and glial cell types. After 14 days in culture, scaffolds supported epithelial, smooth muscle and glial cell phenotypes. Transplanted constructs integrated into the host's native tissue and recipients of the engineered tissue demonstrated normal feeding habits. Characterization after 14 days of implantation revealed that all three cellular phenotypes were present in varying degrees in seeded and unseeded scaffolds. We demonstrate that isolated cells from native esophagus can be cultured and seeded onto electrospun scaffolds to create esophageal constructs. These constructs have potential translatable application for tissue engineering of human esophageal tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biomaterial-mesenchymal stem cell constructs for immunomodulation in composite tissue engineering.

PubMed

Hanson, Summer; D'Souza, Rena N; Hematti, Peiman

2014-08-01

Cell-based treatments are being developed as a novel approach for the treatment of many diseases in an effort to repair injured tissues and regenerate lost tissues. Interest in the potential use of multipotent progenitor or stem cells has grown significantly in recent years, specifically the use of mesenchymal stem cells (MSCs), for tissue engineering in combination with extracellular matrix-based scaffolds. An area that warrants further attention is the local or systemic host responses toward the implanted cell-biomaterial constructs. Such immunological responses could play a major role in determining the clinical efficacy of the therapeutic device or biomaterials used. MSCs, due to their unique immunomodulatory properties, hold great promise in tissue engineering as they not only directly participate in tissue repair and regeneration but also modulate the host foreign body response toward the engineered constructs. The purpose of this review was to summarize the current state of knowledge and applications of MSC-biomaterial constructs as a potential immunoregulatory tool in tissue engineering. Better understanding of the interactions between biomaterials and cells could translate to the development of clinically relevant and novel cell-based therapeutics for tissue reconstruction and regenerative medicine.

An integrated theoretical-experimental approach to accelerate translational tissue engineering.

PubMed

Coy, Rachel H; Evans, Owen R; Phillips, James B; Shipley, Rebecca J

2018-01-01

Implantable devices utilizing bioengineered tissue are increasingly showing promise as viable clinical solutions. The design of bioengineered constructs is currently directed according to the results of experiments that are used to test a wide range of different combinations and spatial arrangements of biomaterials, cells and chemical factors. There is an outstanding need to accelerate the design process and reduce financial costs, whilst minimizing the required number of animal-based experiments. These aims could be achieved through the incorporation of mathematical modelling as a preliminary design tool. Here we focus on tissue-engineered constructs for peripheral nerve repair, which are designed to aid nerve and blood vessel growth and repair after peripheral nerve injury. We offer insight into the role that mathematical modelling can play within tissue engineering, and motivate the use of modelling as a tool capable of improving and accelerating the design of nerve repair constructs in particular. Specific case studies are presented in order to illustrate the potential of mathematical modelling to direct construct design. Copyright © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd. Copyright © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd.

Constructed Wetlands

EPA Pesticide Factsheets

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

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

PubMed

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.

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

PubMed

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.

The Crosstalk between Tissue Engineering and Pharmaceutical Biotechnology: Recent Advances and Future Directions.

PubMed

Pacheco, Daniela P; Reis, Rui L; Correlo, Vítor M; Marques, Alexandra P

2015-01-01

Tissue-engineered constructs made of biotechnology-derived materials have been preferred due to their chemical and physical composition, which offers both high versatility and a support to enclose/ incorporate relevant signaling molecules and/or genes known to therapeutically induce tissue repair. Herein, a critical overview of the impact of different biotechnology-derived materials, scaffolds, and recombinant signaling molecules over the behavior of cells, another element of tissue engineered constructs, as well its regulatory role in tissue regeneration and disease progression is given. Additionally, these tissue-engineered constructs evolved to three-dimensional (3D) tissue-like models that, as an advancement of two-dimensional standard culture methods, are expected to be a valuable tool in the field of drug discovery and pharmaceutical research. Despite the improved design and conception of current proposed 3D tissue-like models, advanced control systems to enable and accelerate streamlining and automation of the numerous labor-intensive steps intrinsic to the development of tissue-engineered constructs are still to be achieved. In this sense, this review intends to present the biotechnology- derived materials that are being explored in the field of tissue engineering to generate 3D tissue-analogues and briefly highlight their foremost breakthroughs in tissue regeneration and drug discovery. It also aims to reinforce that the crosstalk between tissue engineering and pharmaceutical biotechnology has been fostering the outcomes of tissue engineering approaches through the use of biotechnology-derived signaling molecules. Gene delivery/therapy is also discussed as a forefront area that represents another cross point between tissue engineering and pharmaceutical biotechnology, in which nucleic acids can be considered a "super pharmaceutical" to drive biological responses, including tissue regeneration.

Processes in construction of failure management expert systems from device design information

NASA Technical Reports Server (NTRS)

Malin, Jane T.; Lance, Nick

1987-01-01

This paper analyzes the tasks and problem solving methods used by an engineer in constructing a failure management expert system from design information about the device to te diagnosed. An expert test engineer developed a trouble-shooting expert system based on device design information and experience with similar devices, rather than on specific expert knowledge gained from operating the device or troubleshooting its failures. The construction of the expert system was intensively observed and analyzed. This paper characterizes the knowledge, tasks, methods, and design decisions involved in constructing this type of expert system, and makes recommendations concerning tools for aiding and automating construction of such systems.

48 CFR 227.7107 - Contracts for architect-engineer services.

Code of Federal Regulations, 2014 CFR

2014-10-01

...-engineer services. 227.7107 Section 227.7107 Federal Acquisition Regulations System DEFENSE ACQUISITION... Rights in Technical Data 227.7107 Contracts for architect-engineer services. This section sets forth... of construction and architect-engineer services. ...

48 CFR 227.7107 - Contracts for architect-engineer services.

Code of Federal Regulations, 2011 CFR

2011-10-01

...-engineer services. 227.7107 Section 227.7107 Federal Acquisition Regulations System DEFENSE ACQUISITION... Rights in Technical Data 227.7107 Contracts for architect-engineer services. This section sets forth... of construction and architect-engineer services. ...

48 CFR 227.7107 - Contracts for architect-engineer services.

Code of Federal Regulations, 2013 CFR

2013-10-01

...-engineer services. 227.7107 Section 227.7107 Federal Acquisition Regulations System DEFENSE ACQUISITION... Rights in Technical Data 227.7107 Contracts for architect-engineer services. This section sets forth... of construction and architect-engineer services. ...

48 CFR 227.7107 - Contracts for architect-engineer services.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-engineer services. 227.7107 Section 227.7107 Federal Acquisition Regulations System DEFENSE ACQUISITION... Rights in Technical Data 227.7107 Contracts for architect-engineer services. This section sets forth... of construction and architect-engineer services. ...

48 CFR 227.7107 - Contracts for architect-engineer services.

Code of Federal Regulations, 2012 CFR

2012-10-01

...-engineer services. 227.7107 Section 227.7107 Federal Acquisition Regulations System DEFENSE ACQUISITION... Rights in Technical Data 227.7107 Contracts for architect-engineer services. This section sets forth... of construction and architect-engineer services. ...

Students' Changing Images of Engineering and Engineers. Research Brief

ERIC Educational Resources Information Center

Jocuns, Andrew; Stevens, Reed; Garrison, Lari; Amos, Daniel

2008-01-01

This study analyzes the images of engineers and engineering that students construct over the course of their undergraduate engineering educations. Students in their first year of study to become engineers knew very little about the work they would be doing as an engineer and their expectations were more specific, hopeful, and high status than…

A Method for Search Engine Selection using Thesaurus for Selective Meta-Search Engine

NASA Astrophysics Data System (ADS)

Goto, Shoji; Ozono, Tadachika; Shintani, Toramatsu

In this paper, we propose a new method for selecting search engines on WWW for selective meta-search engine. In selective meta-search engine, a method is needed that would enable selecting appropriate search engines for users' queries. Most existing methods use statistical data such as document frequency. These methods may select inappropriate search engines if a query contains polysemous words. In this paper, we describe an search engine selection method based on thesaurus. In our method, a thesaurus is constructed from documents in a search engine and is used as a source description of the search engine. The form of a particular thesaurus depends on the documents used for its construction. Our method enables search engine selection by considering relationship between terms and overcomes the problems caused by polysemous words. Further, our method does not have a centralized broker maintaining data, such as document frequency for all search engines. As a result, it is easy to add a new search engine, and meta-search engines become more scalable with our method compared to other existing methods.

Recent Progress on Systems and Synthetic Biology Approaches to Engineer Fungi As Microbial Cell Factories.

PubMed

Amores, Gerardo Ruiz; Guazzaroni, María-Eugenia; Arruda, Letícia Magalhães; Silva-Rocha, Rafael

2016-04-01

Filamentous fungi are remarkable organisms naturally specialized in deconstructing plant biomass and this feature has a tremendous potential for biofuel production from renewable sources. The past decades have been marked by a remarkable progress in the genetic engineering of fungi to generate industry-compatible strains needed for some biotech applications. In this sense, progress in this field has been marked by the utilization of high-throughput techniques to gain deep understanding of the molecular machinery controlling the physiology of these organisms, starting thus the Systems Biology era of fungi. Additionally, genetic engineering has been extensively applied to modify wellcharacterized promoters in order to construct new expression systems with enhanced performance under the conditions of interest. In this review, we discuss some aspects related to significant progress in the understating and engineering of fungi for biotechnological applications, with special focus on the construction of synthetic promoters and circuits in organisms relevant for industry. Different engineering approaches are shown, and their potential and limitations for the construction of complex synthetic circuits in these organisms are examined. Finally, we discuss the impact of engineered promoter architecture in the single-cell behavior of the system, an often-neglected relationship with a tremendous impact in the final performance of the process of interest. We expect to provide here some new directions to drive future research directed to the construction of high-performance, engineered fungal strains working as microbial cell factories.

Roles of macrophage migration inhibitory factor in cartilage tissue engineering.

PubMed

Fujihara, Yuko; Hikita, Atsuhiko; Takato, Tsuyoshi; Hoshi, Kazuto

2018-02-01

To obtain stable outcomes in regenerative medicine, understanding and controlling immunological responses in transplanted tissues are of great importance. In our previous study, auricular chondrocytes in tissue-engineered cartilage transplanted in mice were shown to express immunological factors, including macrophage migration inhibitory factor (MIF). Since MIF exerts pleiotropic functions, in this study, we examined the roles of MIF in cartilage regenerative medicine. We made tissue-engineered cartilage consisting of auricular chondrocytes of C57BL/6J mouse, atellocollagen gel and a PLLA scaffold, and transplanted the construct subcutaneously in a syngeneic manner. Localization of MIF was prominent in cartilage areas of tissue-engineered cartilage at 2 weeks after transplantation, though it became less apparent by 8 weeks. Co-culture with RAW264 significantly increased the expression of MIF in chondrocytes, suggesting that the transplanted chondrocytes in tissue-engineered cartilage could enhance the expression of MIF by stimulation of surrounding macrophages. When MIF was added in the culture of chondrocytes, the expression of type II collagen was increased, indicating that MIF could promote the maturation of chondrocytes. Meanwhile, toluidine blue staining of constructs containing wild type (Mif+/+) chondrocytes showed increased metachromasia compared to MIF-knockout (Mif-/-) constructs at 2 weeks. However, this tendency was reversed by 8 weeks, suggesting that the initial increase in cartilage maturation in Mif+/+ constructs deteriorated by 8 weeks. Since the Mif+/+ constructs included more iNOS-positive inflammatory macrophages at 2 weeks, MIF might induce an M1 macrophage-polarized environment, which may eventually worsen the maturation of tissue-engineered cartilage in the long term. © 2017 Wiley Periodicals, Inc.

14 CFR 33.21 - Engine cooling.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine cooling. 33.21 Section 33.21 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.21 Engine cooling. Engine design and...

48 CFR 436.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2012 CFR

2012-10-01

... for architect-engineer work. 436.605 Section 436.605 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Service 436.605 Government cost estimate for architect-engineer work. The contracting...

48 CFR 2436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 2436.602 Section 2436.602 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 2436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 2436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 2436.602 Section 2436.602 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 2436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 436.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2013 CFR

2013-10-01

... for architect-engineer work. 436.605 Section 436.605 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Service 436.605 Government cost estimate for architect-engineer work. The contracting...

48 CFR 2436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 2436.602 Section 2436.602 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 2436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 2436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 2436.602 Section 2436.602 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 2436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 36.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2012 CFR

2012-10-01

... for architect-engineer work. 36.605 Section 36.605 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.605 Government cost estimate for architect-engineer work. (a) An independent...

48 CFR 1336.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2011 CFR

2011-10-01

... for architect-engineer work. 1336.605 Section 1336.605 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1336.605 Government cost estimate for architect-engineer work. After award, the...

48 CFR 1336.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2012 CFR

2012-10-01

... for architect-engineer work. 1336.605 Section 1336.605 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1336.605 Government cost estimate for architect-engineer work. After award, the...

48 CFR 2436.602 - Selection of firms for architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 2436.602 Section 2436.602 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 2436.602 Selection of firms for architect-engineer contracts. ...

48 CFR 1336.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2013 CFR

2013-10-01

... for architect-engineer work. 1336.605 Section 1336.605 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1336.605 Government cost estimate for architect-engineer work. After award, the...

48 CFR 36.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2014 CFR

2014-10-01

... for architect-engineer work. 36.605 Section 36.605 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.605 Government cost estimate for architect-engineer work. (a) An independent...

48 CFR 36.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2010 CFR

2010-10-01

... for architect-engineer work. 36.605 Section 36.605 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.605 Government cost estimate for architect-engineer work. (a) An independent...

48 CFR 436.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2011 CFR

2011-10-01

... for architect-engineer work. 436.605 Section 436.605 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Service 436.605 Government cost estimate for architect-engineer work. The contracting...

48 CFR 436.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2010 CFR

2010-10-01

... for architect-engineer work. 436.605 Section 436.605 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Service 436.605 Government cost estimate for architect-engineer work. The contracting...

48 CFR 1336.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2010 CFR

2010-10-01

... for architect-engineer work. 1336.605 Section 1336.605 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1336.605 Government cost estimate for architect-engineer work. After award, the...

48 CFR 36.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2013 CFR

2013-10-01

... for architect-engineer work. 36.605 Section 36.605 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.605 Government cost estimate for architect-engineer work. (a) An independent...

48 CFR 436.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2014 CFR

2014-10-01

... for architect-engineer work. 436.605 Section 436.605 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Service 436.605 Government cost estimate for architect-engineer work. The contracting...

48 CFR 36.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2011 CFR

2011-10-01

... for architect-engineer work. 36.605 Section 36.605 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.605 Government cost estimate for architect-engineer work. (a) An independent...

48 CFR 1336.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2014 CFR

2014-10-01

... for architect-engineer work. 1336.605 Section 1336.605 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 1336.605 Government cost estimate for architect-engineer work. After award, the...

14 CFR 33.21 - Engine cooling.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Engine cooling. 33.21 Section 33.21 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.21 Engine cooling. Engine design and...

14 CFR 33.21 - Engine cooling.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Engine cooling. 33.21 Section 33.21 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.21 Engine cooling. Engine design and...

14 CFR 33.21 - Engine cooling.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Engine cooling. 33.21 Section 33.21 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.21 Engine cooling. Engine design and...

14 CFR 33.21 - Engine cooling.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Engine cooling. 33.21 Section 33.21 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.21 Engine cooling. Engine design and...

A System-Science Approach towards Model Construction for Curriculum Development.

ERIC Educational Resources Information Center

Chang, Ren-Jung; Yang, Hui-Chin

A new morphological model based on modern system science and engineering is constructed and proposed for curriculum research and development. A curriculum system is recognized as an engineering system that constitutes three components: clients, resources, and knowledge. Unlike the objective models that are purely rational and neatly sequential in…

REACTIVITY MEASUREMENT FACILITY, UNDER CONSTRUCTION OVER MTR CANAL IN BASEMENT ...

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

REACTIVITY MEASUREMENT FACILITY, UNDER CONSTRUCTION OVER MTR CANAL IN BASEMENT OF MTR BUILDING, TRA-603. WOOD PLANKS REST ON CANAL WALL OBSERVABLE IN FOREGROUND. INL NEGATIVE NO. 11745. Unknown Photographer, 8/20/1954 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Corporate Consolidation: An Event Study of Historic Stock Prices in the Defense Aerospace Industry

DTIC Science & Technology

2009-12-01

1994 Raytheon Xyplex Inc 1/3/1995 Boeing Precision Gear 4/3/1995 Raytheon Raytheon E-Systems Inc 6/30/1995 Raytheon Litwin Engineers & Construction...Acquirer 6/30/1995 Litwin Engineers & Construction Raytheon Arithmetic Return Logarithmic Return Note: * is significant at the 5% level 90

Women and Girls on Engineering and Construction Courses in Further Education.

ERIC Educational Resources Information Center

Chiosso, Ros; Tizard, Jenny

1990-01-01

Interviews with 10 female students in construction and engineering courses at Keighley College (Great Britain) found that they experienced problems with harassment from male students, isolation, and lecturers' attitudes. Recommendations were to increase the numbers of women students, encourage them to support each other, improve the induction…

A study of competence in mathematics and mechanics in an engineering curriculum

NASA Astrophysics Data System (ADS)

Munns, Andrew

2017-11-01

Professional bodies expect engineers to show competence in both mathematics and engineering topics such as mechanics, using their abilities in both of these to solve problems. Yet within engineering programmes there is a phenomenon known as 'The Mathematics Problem', with students not demonstrating understanding of the subject. This paper will suggest that students are constructing different concept images in engineering and mathematics, based on their perception of either the use or exchange-value for the topics. Using a mixed methods approach, the paper compares 10 different types of concept image constructed by students, which suggests that familiar procedural images are preferred in mathematics. In contrast strategic and conceptual images develop for mechanics throughout the years of the programme, implying that different forms of competence are being constructed by students between the two subjects. The paper argues that this difference is attributed to the perceived use-value of mechanics in the career of the engineer, compared to the exchange-value associated with mathematics. Questions are raised about the relevance of current definitions of competence given that some routine mathematical operations previously performed by engineers are now being replaced by technology, in the new world of work.

Assessing and Controlling Blast Noise Emission: SARNAM Noise Impact Software

DTIC Science & Technology

2007-12-29

Engineers, Engineer Research and Development Center Jeffery Mifflin U.S. Army Corps of Engineers, Engineer Research and Development Center Kristy A...PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Army Engineer Research and Development Center (ERDC) Construction Engineering Research Laboratory...6 Figure 5. OneShot control page

Hydrogels for Engineering of Perfusable Vascular Networks

PubMed Central

Liu, Juan; Zheng, Huaiyuan; Poh, Patrina S. P.; Machens, Hans-Günther; Schilling, Arndt F.

2015-01-01

Hydrogels are commonly used biomaterials for tissue engineering. With their high-water content, good biocompatibility and biodegradability they resemble the natural extracellular environment and have been widely used as scaffolds for 3D cell culture and studies of cell biology. The possible size of such hydrogel constructs with embedded cells is limited by the cellular demand for oxygen and nutrients. For the fabrication of large and complex tissue constructs, vascular structures become necessary within the hydrogels to supply the encapsulated cells. In this review, we discuss the types of hydrogels that are currently used for the fabrication of constructs with embedded vascular networks, the key properties of hydrogels needed for this purpose and current techniques to engineer perfusable vascular structures into these hydrogels. We then discuss directions for future research aimed at engineering of vascularized tissue for implantation. PMID:26184185

7 CFR 1753.82 - Minor construction closeout.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 11 2011-01-01 2011-01-01 false Minor construction closeout. 1753.82 Section 1753.82... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Minor Construction § 1753.82 Minor construction closeout. (a) For minor construction inspected by the borrower's engineer, an original and two...

7 CFR 1753.82 - Minor construction closeout.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 11 2010-01-01 2010-01-01 false Minor construction closeout. 1753.82 Section 1753.82... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Minor Construction § 1753.82 Minor construction closeout. (a) For minor construction inspected by the borrower's engineer, an original and two...

Development of large engineered cartilage constructs from a small population of cells.

PubMed

Brenner, Jillian M; Kunz, Manuela; Tse, Man Yat; Winterborn, Andrew; Bardana, Davide D; Pang, Stephen C; Waldman, Stephen D

2013-01-01

Confronted with articular cartilage's limited capacity for self-repair, joint resurfacing techniques offer an attractive treatment for damaged or diseased tissue. Although tissue engineered cartilage constructs can be created, a substantial number of cells are required to generate sufficient quantities of tissue for the repair of large defects. As routine cell expansion methods tend to elicit negative effects on chondrocyte function, we have developed an approach to generate phenotypically stable, large-sized engineered constructs (≥3 cm(2) ) directly from a small amount of donor tissue or cells (as little as 20,000 cells to generate a 3 cm(2) tissue construct). Using rabbit donor tissue, the bioreactor-cultivated constructs were hyaline-like in appearance and possessed a biochemical composition similar to native articular cartilage. Longer bioreactor cultivation times resulted in increased matrix deposition and improved mechanical properties determined over a 4 week period. Additionally, as the anatomy of the joint will need to be taken in account to effectively resurface large affected areas, we have also explored the possibility of generating constructs matched to the shape and surface geometry of a defect site through the use of rapid-prototyped defect tissue culture molds. Similar hyaline-like tissue constructs were developed that also possessed a high degree of shape correlation to the original defect mold. Future studies will be aimed at determining the effectiveness of this approach to the repair of cartilage defects in an animal model and the creation of large-sized osteochondral constructs. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

Enhanced nutrient transport improves the depth-dependent properties of tri-layered engineered cartilage constructs with zonal co-culture of chondrocytes and MSCs.

PubMed

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 and mechanical properties of native cartilage while minimizing the need for large numbers of chondrocytes. In addition, introduction of a porous hollow fiber (combined with a cotton thread) enhanced nutrient transport and depth-dependent properties of the tri-layered construct. Such a tri-layered construct may provide critical advantages for focal cartilage repair. These constructs hold promise for restoring native tissue structure and function, and may be beneficial in terms of zone-to-zone integration with adjacent host tissue and providing more appropriate strain transfer after implantation. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Recent Efforts and Experiments in the Construction of Aviation Engines

NASA Technical Reports Server (NTRS)

SCHWAGER

1920-01-01

It became evident during World War I that ever-increasing demands were being placed on the mean power of aircraft engines as a result of the increased on board equipment and the demands of aerial combat. The need was for increased climbing efficiency and climbing speed. The response to these demands has been in terms of lightweight construction and the adaptation of the aircraft engine to the requirements of its use. Discussed here are specific efforts to increase flying efficiency, such as reduction of the number of revolutions of the propeller from 1400 to about 900 r.p.m. through the use of a reduction gear, increasing piston velocity, locating two crankshafts in one gear box, and using the two-cycle stroke. Also discussed are improvements in the transformation of fuel energy into engine power, the raising of compression ratios, the use of super-compression with carburetors constructed for high altitudes, the use of turbo-compressors, rotary engines, and the use of variable pitch propellers.

14 CFR 33.63 - Vibration.

Code of Federal Regulations, 2011 CFR

2011-01-01

... and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.63 Vibration. Each engine... range of rotational speeds and power/thrust, without inducing excessive stress in any engine part...

14 CFR 33.63 - Vibration.

Code of Federal Regulations, 2010 CFR

2010-01-01

... and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.63 Vibration. Each engine... range of rotational speeds and power/thrust, without inducing excessive stress in any engine part...

Science and Engineering

ERIC Educational Resources Information Center

Cowin, Roy; Reyes-Guerra, David

1977-01-01

Engineers may be involved in various functions such as research, development, planning, design (analysis and synthesis), construction, operation and management of engineering projects. This article discusses some branches of accredited engineering curricula, employment opportunities, the preparation for management, minimum education needed, women…

Cells for tissue engineering of cardiac valves.

PubMed

Jana, Soumen; Tranquillo, Robert T; Lerman, Amir

2016-10-01

Heart valve tissue engineering is a promising alternative to prostheses for the replacement of diseased or damaged heart valves, because tissue-engineered valves have the ability to remodel, regenerate and grow. To engineer heart valves, cells are harvested, seeded onto or into a three-dimensional (3D) matrix platform to generate a tissue-engineered construct in vitro, and then implanted into a patient's body. Successful engineering of heart valves requires a thorough understanding of the different types of cells that can be used to obtain the essential phenotypes that are expressed in native heart valves. This article reviews different cell types that have been used in heart valve engineering, cell sources for harvesting, phenotypic expression in constructs and suitability in heart valve tissue engineering. Natural and synthetic biomaterials that have been applied as scaffold systems or cell-delivery platforms are discussed with each cell type. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Army Corps of Engineers: Better Guidance Could Improve Corps’ Information on Water Resources Projects Undertaken by Nonfederal Sponsors

DTIC Science & Technology

2016-12-01

Nonfederal Sponsors Why GAO Did This Study Through its Civil Works program, the Corps designs , constructs, and maintains federal water resources...Public Works United States Senate Dear Mr. Chairman: The U.S. Army Corps of Engineers (Corps) is the world’s largest public engineering, design ...its Civil Works Program, in general, the Corps plans, designs , constructs, operates, and maintains a wide range of water resources projects. Congress

7 CFR 1753.17 - Engineering services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 11 2014-01-01 2014-01-01 false Engineering services. 1753.17 Section 1753.17... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Engineering Services § 1753.17 Engineering services. (a)(1) All engineering services required by a borrower to support its application for a...

7 CFR 1753.17 - Engineering services.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 11 2010-01-01 2010-01-01 false Engineering services. 1753.17 Section 1753.17... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Engineering Services § 1753.17 Engineering services. (a)(1) All engineering services required by a borrower to support its application for a...

7 CFR 1753.17 - Engineering services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 11 2011-01-01 2011-01-01 false Engineering services. 1753.17 Section 1753.17... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Engineering Services § 1753.17 Engineering services. (a)(1) All engineering services required by a borrower to support its application for a...

7 CFR 1753.17 - Engineering services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 11 2013-01-01 2013-01-01 false Engineering services. 1753.17 Section 1753.17... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Engineering Services § 1753.17 Engineering services. (a)(1) All engineering services required by a borrower to support its application for a...

7 CFR 1753.17 - Engineering services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 11 2012-01-01 2012-01-01 false Engineering services. 1753.17 Section 1753.17... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Engineering Services § 1753.17 Engineering services. (a)(1) All engineering services required by a borrower to support its application for a...

48 CFR 36.609-3 - Work oversight in architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 36.609-3 Section 36.609-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.609-3 Work oversight in architect-engineer contracts. The contracting officer...

48 CFR 836.606-71 - Architect-engineer's proposal.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Architect-engineer's... AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.606-71 Architect-engineer's proposal. (a) When the contract price is estimated to be $50,000...

48 CFR 836.606-71 - Architect-engineer's proposal.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Architect-engineer's... AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.606-71 Architect-engineer's proposal. (a) When the contract price is estimated to be $50,000...

48 CFR 836.606-71 - Architect-engineer's proposal.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Architect-engineer's... AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.606-71 Architect-engineer's proposal. (a) When the contract price is estimated to be $50,000...

48 CFR 36.609-3 - Work oversight in architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 36.609-3 Section 36.609-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.609-3 Work oversight in architect-engineer contracts. The contracting officer...

48 CFR 36.609-3 - Work oversight in architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 36.609-3 Section 36.609-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.609-3 Work oversight in architect-engineer contracts. The contracting officer...

48 CFR 36.609-3 - Work oversight in architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 36.609-3 Section 36.609-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.609-3 Work oversight in architect-engineer contracts. The contracting officer...

48 CFR 836.606-71 - Architect-engineer's proposal.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Architect-engineer's... AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.606-71 Architect-engineer's proposal. (a) When the contract price is estimated to be $50,000...

48 CFR 836.606-71 - Architect-engineer's proposal.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Architect-engineer's... AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.606-71 Architect-engineer's proposal. (a) When the contract price is estimated to be $50,000...

48 CFR 36.609-3 - Work oversight in architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 36.609-3 Section 36.609-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 36.609-3 Work oversight in architect-engineer contracts. The contracting officer...

Silk: a potential medium for tissue engineering.

PubMed

Sobajo, Cassandra; Behzad, Farhad; Yuan, Xue-Feng; Bayat, Ardeshir

2008-01-01

Human skin is a complex bilayered organ that serves as a protective barrier against the environment. The loss of integrity of skin by traumatic experiences such as burns and ulcers may result in considerable disability or ultimately death. Therefore, in skin injuries, adequate dermal substitutes are among primary care targets, aimed at replacing the structural and functional properties of native skin. To date, there are very few single application tissue-engineered dermal constructs fulfilling this criterion. Silk produced by the domestic silkworm, Bombyx mori, has a long history of use in medicine. It has recently been increasingly investigated as a promising biomaterial for dermal constructs. Silk contains 2 fibrous proteins, sericin and fibroin. Each one exhibits unique mechanical and biological properties. Comprehensive review of randomized-controlled trials investigating current dermal constructs and the structures and properties of silk-based constructs on wound healing. This review revealed that silk-fibroin is regarded as the most promising biomaterial, providing options for the construction of tissue-engineered skin. The research available indicates that silk fibroin is a suitable biomaterial scaffold for the provision of adequate dermal constructs.

Challenges in Construction Over Soft Soil - Case Studies in Malaysia

NASA Astrophysics Data System (ADS)

Mohamad, N. O.; Razali, C. E.; Hadi, A. A. A.; Som, P. P.; Eng, B. C.; Rusli, M. B.; Mohamad, F. R.

2016-07-01

Construction on soft ground area is a great challenge in the field of geotechnical engineering. Many engineering problems in the form of slope instability, bearing capacity failure or excessive settlement could occur either during or after the construction phase due to low shear strength and high compressibility of this soil. As main technical agencies responsible for implementation of development projects for Government of Malaysia, Public Works Department has vast experience in dealing with this problematic soil over the years. This paper discussed and elaborate on the engineering problems encountered in construction projects that have been carried out by PWD, namely Core Facilities Building of Polytechnic Kota Kinabalu in Sabah and Hospital Tengku Ampuan Rahimah Integration Quarters in Klang, Selangor. Instability of the ground during construction works had caused delay and cost overrun in completion of the project in Selangor, whereas occurrence of continuous post construction settlement had affected the integrity and serviceability of the building in Sabah. The causes of failure and proposed rehabilitation work for both projects also will be discussed in brief.

Time pressure in scenario-based online construction safety quizzes and its effect on students' performance

NASA Astrophysics Data System (ADS)

Jaeger, Martin; Adair, Desmond

2017-05-01

Online quizzes have been shown to be effective learning and assessment approaches. However, if scenario-based online construction safety quizzes do not include time pressure similar to real-world situations, they reflect situations too ideally. The purpose of this paper is to compare engineering students' performance when carrying out an online construction safety quiz with time pressure versus an online construction safety quiz without time pressure. Two versions of an online construction safety quiz are developed and administered to randomly assigned engineering students based on a quasi-experimental post-test design. The findings contribute to scenario-based learning and assessment of construction safety in four ways. First, the results confirm earlier findings that 'intrinsic stress' does not seem to impair students' performance. Second, students who carry out the online construction safety quiz with time pressure are less likely to 'learn by trial and error'. Third, students exposed to time pressure appreciate that they become better prepared for real life. Finally, preparing students to work under time pressure is an important industry requirement. The results of this study should encourage engineering educators to explore and implement ways to include time pressure in scenario-based online quizzes and learning.

8. Historic photo taken during construction of the Lost River ...

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

8. Historic photo taken during construction of the Lost River Diversion Dam and House. Labeled as follows, 'View showing walk construction North side. Group in foreground, left to right: - J.M. McLean, I.S. Voorhees, Asst Eng'r, A.B. Clevland, engineer... W.W. Patch, Project Engineer.' Negative # 95. Facing east. - Klamath Basin Project, Lost River Diversion Dam House, Lost River near intersection of State Highway 140 & Hill Road, Klamath Falls, Klamath County, OR

Application and Mechanics Analysis of Multi-Function Construction Platforms in Prefabricated-Concrete Construction

NASA Astrophysics Data System (ADS)

Wang, Meihua; Li, Rongshuai; Zhang, Wenze

2017-11-01

Multi-function construction platforms (MCPs) as an “old construction technology, new application” of the building facade construction equipment, its efforts to reduce labour intensity, improve labour productivity, ensure construction safety, shorten the duration of construction and other aspects of the effect are significant. In this study, the functional analysis of the multi-function construction platforms is carried out in the construction of the assembly building. Based on the general finite element software ANSYS, the static calculation and dynamic characteristics analysis of the MCPs structure are analysed, the simplified finite element model is constructed, and the selection of the unit, the processing and solution of boundary are under discussion and research. The maximum deformation value, the maximum stress value and the structural dynamic characteristic model are obtained. The dangerous parts of the platform structure are analysed, too. Multiple types of MCPs under engineering construction conditions are calculated, so as to put forward the rationalization suggestions for engineering application of the MCPs.

48 CFR 48.102 - Policies.

Code of Federal Regulations, 2010 CFR

2010-10-01

... VALUE ENGINEERING Policies and Procedures 48.102 Policies. (a) As required by Section 36 of the Office... cost-effective value engineering procedures and processes. Agencies shall provide contractors a... engineering provisions in appropriate supply, service, architect-engineer and construction contracts as...

48 CFR 836.606-73 - Application of 6 percent architect-engineer fee limitation.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer fee limitation. 836.606-73 Section 836.606-73 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.606-73 Application of 6 percent architect-engineer fee limitation...

48 CFR 836.606-73 - Application of 6 percent architect-engineer fee limitation.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer fee limitation. 836.606-73 Section 836.606-73 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.606-73 Application of 6 percent architect-engineer fee limitation...

48 CFR 836.606-73 - Application of 6 percent architect-engineer fee limitation.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer fee limitation. 836.606-73 Section 836.606-73 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.606-73 Application of 6 percent architect-engineer fee limitation...

48 CFR 836.606-73 - Application of 6 percent architect-engineer fee limitation.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer fee limitation. 836.606-73 Section 836.606-73 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.606-73 Application of 6 percent architect-engineer fee limitation...

14 CFR 33.70 - Engine life-limited parts.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine life-limited parts. 33.70 Section 33.70 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.70 Engine life...

14 CFR 33.70 - Engine life-limited parts.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Engine life-limited parts. 33.70 Section 33.70 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.70 Engine life...

48 CFR 736.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2013 CFR

2013-10-01

... for architect-engineer work. 736.605 Section 736.605 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 736.605 Government cost estimate for architect-engineer work. See 736.602-3(c)(5). ...

48 CFR 736.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2010 CFR

2010-10-01

... for architect-engineer work. 736.605 Section 736.605 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 736.605 Government cost estimate for architect-engineer work. See 736.602-3(c)(5). ...

48 CFR 736.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2014 CFR

2014-10-01

... for architect-engineer work. 736.605 Section 736.605 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 736.605 Government cost estimate for architect-engineer work. See 736.602-3(c)(5). ...

48 CFR 736.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2012 CFR

2012-10-01

... for architect-engineer work. 736.605 Section 736.605 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 736.605 Government cost estimate for architect-engineer work. See 736.602-3(c)(5). ...

48 CFR 736.605 - Government cost estimate for architect-engineer work.

Code of Federal Regulations, 2011 CFR

2011-10-01

... for architect-engineer work. 736.605 Section 736.605 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 736.605 Government cost estimate for architect-engineer work. See 736.602-3(c)(5). ...

Detonation Jet Engine. Part 2--Construction Features

ERIC Educational Resources Information Center

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…

A High School Level Course On Robot Design And Construction

NASA Astrophysics Data System (ADS)

Sadler, Paul M.; Crandall, Jack L.

1984-02-01

The Robotics Design and Construction Class at Sehome High School was developed to offer gifted and/or highly motivated students an in-depth introduction to a modern engineering topic. The course includes instruction in basic electronics, digital and radio electronics, construction skills, robotics literacy, construction of the HERO 1 Heathkit Robot, computer/ robot programming, and voice synthesis. A key element which leads to the success of the course is the involvement of various community assets including manpower and financial assistance. The instructors included a physics/electronics teacher, a computer science teacher, two retired engineers, and an electronics technician.

Preparedness Portfolios and Portfolio Studios: Supporting Self-Authoring Engineers

ERIC Educational Resources Information Center

Sattler, Brook; Turns, Jennifer

2015-01-01

In this work, we engaged engineering undergraduate students in constructing an ePortfolio. The purpose of the research presented here was to explore the question, "If and in what ways do students report experiencing the construction of a preparedness portfolio in a portfolio studio as an opportunity to develop into self-authoring…

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

PubMed

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.

Biomimetic approach to cardiac tissue engineering.

PubMed

Radisic, M; Park, H; Gerecht, S; Cannizzaro, C; Langer, R; Vunjak-Novakovic, G

2007-08-29

Here, we review an approach to tissue engineering of functional myocardium that is biomimetic in nature, as it involves the use of culture systems designed to recapitulate some aspects of the actual in vivo environment. To mimic the capillary network, subpopulations of neonatal rat heart cells were cultured on a highly porous elastomer scaffold with a parallel array of channels perfused with culture medium. To mimic oxygen supply by haemoglobin, the culture medium was supplemented with a perfluorocarbon (PFC) emulsion. Constructs cultivated in the presence of PFC contained higher amounts of DNA and cardiac markers and had significantly better contractile properties than control constructs cultured without PFC. To induce synchronous contractions of cultured constructs, electrical signals mimicking those in native heart were applied. Over only 8 days of cultivation, electrical stimulation induced cell alignment and coupling, markedly increased the amplitude of synchronous construct contractions and resulted in a remarkable level of ultrastructural organization. The biomimetic approach is discussed in the overall context of cardiac tissue engineering, and the possibility to engineer functional human cardiac grafts based on human stem cells.

Novel technique for online characterization of cartilaginous tissue properties.

PubMed

Yuan, Tai-Yi; Huang, Chun-Yuh; Yong Gu, Wei

2011-09-01

The goal of tissue engineering is to use substitutes to repair and restore organ function. Bioreactors are an indispensable tool for monitoring and controlling the unique environment for engineered constructs to grow. However, in order to determine the biochemical properties of engineered constructs, samples need to be destroyed. In this study, we developed a novel technique to nondestructively online-characterize the water content and fixed charge density of cartilaginous tissues. A new technique was developed to determine the tissue mechano-electrochemical properties nondestructively. Bovine knee articular cartilage and lumbar annulus fibrosus were used in this study to demonstrate that this technique could be used on different types of tissue. The results show that our newly developed method is capable of precisely predicting the water volume fraction (less than 3% disparity) and fixed charge density (less than 16.7% disparity) within cartilaginous tissues. This novel technique will help to design a new generation of bioreactors which are able to actively determine the essential properties of the engineered constructs, as well as regulate the local environment to achieve the optimal conditions for cultivating constructs.

The fusion of biology, computer science, and engineering: towards efficient and successful synthetic biology.

PubMed

Linshiz, Gregory; Goldberg, Alex; Konry, Tania; Hillson, Nathan J

2012-01-01

Synthetic biology is a nascent field that emerged in earnest only around the turn of the millennium. It aims to engineer new biological systems and impart new biological functionality, often through genetic modifications. The design and construction of new biological systems is a complex, multistep process, requiring multidisciplinary collaborative efforts from "fusion" scientists who have formal training in computer science or engineering, as well as hands-on biological expertise. The public has high expectations for synthetic biology and eagerly anticipates the development of solutions to the major challenges facing humanity. This article discusses laboratory practices and the conduct of research in synthetic biology. It argues that the fusion science approach, which integrates biology with computer science and engineering best practices, including standardization, process optimization, computer-aided design and laboratory automation, miniaturization, and systematic management, will increase the predictability and reproducibility of experiments and lead to breakthroughs in the construction of new biological systems. The article also discusses several successful fusion projects, including the development of software tools for DNA construction design automation, recursive DNA construction, and the development of integrated microfluidics systems.

48 CFR 236.275 - Construction of industrial resources.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Construction of industrial... SYSTEM, DEPARTMENT OF DEFENSE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 236.275 Construction of industrial resources. See...

48 CFR 236.275 - Construction of industrial resources.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Construction of industrial... SYSTEM, DEPARTMENT OF DEFENSE SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Special Aspects of Contracting for Construction 236.275 Construction of industrial resources. See...

Construction Sector (NAICS 23)

EPA Pesticide Factsheets

Find environmental regulatory information for the construction sector, including the construction of buildings or engineering projects. This includes RCRA information for hazardous waste, refrigeration compliance, asbestos, effluent guidelines & lead laws

Temporal development of near-native functional properties and correlations with qMRI in self-assembling fibrocartilage treated with exogenous lysyl oxidase homolog 2.

PubMed

Hadidi, Pasha; Cissell, Derek D; Hu, Jerry C; Athanasiou, Kyriacos A

2017-12-01

Advances in cartilage tissue engineering have led to constructs with mechanical integrity and biochemical composition increasingly resembling that of native tissues. In particular, collagen cross-linking with lysyl oxidase has been used to significantly enhance the mechanical properties of engineered neotissues. In this study, development of collagen cross-links over time, and correlations with tensile properties, were examined in self-assembling neotissues. Additionally, quantitative MRI metrics were examined in relation to construct mechanical properties as well as pyridinoline cross-link content and other engineered tissue components. Scaffold-free meniscus fibrocartilage was cultured in the presence of exogenous lysyl oxidase, and assessed at multiple time points over 8weeks starting from the first week of culture. Engineered constructs demonstrated a 9.9-fold increase in pyridinoline content, reaching 77% of native tissue values, after 8weeks of culture. Additionally, engineered tissues reached 66% of the Young's modulus in the radial direction of native tissues. Further, collagen cross-links were found to correlate with tensile properties, contributing 67% of the tensile strength of engineered neocartilages. Finally, examination of quantitative MRI metrics revealed several correlations with mechanical and biochemical properties of engineered constructs. This study displays the importance of culture duration for collagen cross-link formation, and demonstrates the potential of quantitative MRI in investigating properties of engineered cartilages. This is the first study to demonstrate near-native cross-link content in an engineered tissue, and the first study to quantify pyridinoline cross-link development over time in a self-assembling tissue. Additionally, this work shows the relative contributions of collagen and pyridinoline to the tensile properties of collagenous tissue for the first time. Furthermore, this is the first investigation to identify a relationship between qMRI metrics and the pyridinoline cross-link content of an engineered collagenous tissue. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Combined protein construct and synthetic gene engineering for heterologous protein expression and crystallization using Gene Composer

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

Raymond, Amy; Lovell, Scott; Lorimer, Don

2009-12-01

With the goal of improving yield and success rates of heterologous protein production for structural studies we have developed the database and algorithm software package Gene Composer. This freely available electronic tool facilitates the information-rich design of protein constructs and their engineered synthetic gene sequences, as detailed in the accompanying manuscript. In this report, we compare heterologous protein expression levels from native sequences to that of codon engineered synthetic gene constructs designed by Gene Composer. A test set of proteins including a human kinase (P38{alpha}), viral polymerase (HCV NS5B), and bacterial structural protein (FtsZ) were expressed in both E. colimore » and a cell-free wheat germ translation system. We also compare the protein expression levels in E. coli for a set of 11 different proteins with greatly varied G:C content and codon bias. The results consistently demonstrate that protein yields from codon engineered Gene Composer designs are as good as or better than those achieved from the synonymous native genes. Moreover, structure guided N- and C-terminal deletion constructs designed with the aid of Gene Composer can lead to greater success in gene to structure work as exemplified by the X-ray crystallographic structure determination of FtsZ from Bacillus subtilis. These results validate the Gene Composer algorithms, and suggest that using a combination of synthetic gene and protein construct engineering tools can improve the economics of gene to structure research.« less

A Visualization-Based Tutoring Tool for Engineering Education

NASA Astrophysics Data System (ADS)

Nguyen, Tang-Hung; Khoo, I.-Hung

2010-06-01

In engineering disciplines, students usually have hard time to visualize different aspects of engineering analysis and design, which inherently are too complex or abstract to fully understand without the aid of visual explanations or visualizations. As examples, when learning materials and sequences of construction process, students need to visualize how all components of a constructed facility are assembled? Such visualization can not be achieved in a textbook and a traditional lecturing environment. In this paper, the authors present the development of a computer tutoring software, in which different visualization tools including video clips, 3 dimensional models, drawings, pictures/photos together with complementary texts are used to assist students in deeply understanding and effectively mastering materials. The paper will also discuss the implementation and the effectiveness evaluation of the proposed tutoring software, which was used to teach a construction engineering management course offered at California State University, Long Beach.

Fiber-Based Tissue Engineering: Progress, Challenges, and Opportunities

PubMed Central

Tamayol, Ali; Akbari, Mohsen; Annabi, Nasim; Paul, Arghya; Khademhosseini, Ali; Juncker, David

2013-01-01

Tissue engineering aims to improve the function of diseased or damaged organs by creating biological substitutes. To fabricate a functional tissue, the engineered construct should mimic the physiological environment including its structural, topographical, and mechanical properties. Moreover, the construct should facilitate nutrients and oxygen diffusion as well as removal of metabolic waste during tissue regeneration. In the last decade, fiber-based techniques such as weaving, knitting, braiding, as well as electrospinning, and direct writing have emerged as promising platforms for making 3D tissue constructs that can address the above mentioned challenges. Here, we critically review the techniques used to form cell-free and cell-laden fibers and to assemble them into scaffolds. We compare their mechanical properties, morphological features and biological activity. We discuss current challenges and future opportunities of fiber-based tissue engineering (FBTE) for use in research and clinical practice. PMID:23195284

Functional assembly of engineered myocardium by electrical stimulation of cardiac myocytes cultured on scaffolds.

PubMed

Radisic, Milica; Park, Hyoungshin; Shing, Helen; Consi, Thomas; Schoen, Frederick J; Langer, Robert; Freed, Lisa E; Vunjak-Novakovic, Gordana

2004-12-28

The major challenge of tissue engineering is directing the cells to establish the physiological structure and function of the tissue being replaced across different hierarchical scales. To engineer myocardium, biophysical regulation of the cells needs to recapitulate multiple signals present in the native heart. We hypothesized that excitation-contraction coupling, critical for the development and function of a normal heart, determines the development and function of engineered myocardium. To induce synchronous contractions of cultured cardiac constructs, we applied electrical signals designed to mimic those in the native heart. Over only 8 days in vitro, electrical field stimulation induced cell alignment and coupling, increased the amplitude of synchronous construct contractions by a factor of 7, and resulted in a remarkable level of ultrastructural organization. Development of conductive and contractile properties of cardiac constructs was concurrent, with strong dependence on the initiation and duration of electrical stimulation.

A Center for Extraterrestrial Engineering and Construction (CETEC)

NASA Technical Reports Server (NTRS)

Leigh, Gerald G.

1992-01-01

A group of knowledgeable scientists and engineers in New Mexico has recognized the need for such a testing capability and has proposed a project to evelop an extraterrestrial surface simulation facility. A group of universities, national laboratories, and private industrial firms is proposing to establish a Center for Extraterrestrial Engineering and Construction (CETEC) and to develop large extraterrestrial surface simulation facilities in which this needed testing can be realistically performed. The CETEC is envisioned to be both a center of knowledge and data regarding engineering, construction, mining, and material process operations on extraterrestrial bodies and a set of extraterrestrial surface simulation facilities. The primary CETEC facility is proposed to be a large domed building made of steel reinforced concrete with more than one acre of test floor area covered with several feet of simulated lunar soil and dust. Various aspects of the project are presented in viewgraph form.

Distinction of Concept and Discussion on Construction Idea of Smart Water Grid Project

NASA Astrophysics Data System (ADS)

Ye, Y.; Yizi, S., Sr.; Lili, L., Sr.; Sang, X.; Zhai, J.

2016-12-01

Smart water grid project includes construction of water physical grid consisting of various flow regulating infrastructures, construction of water information grid in line with the trend of intelligent technology and construction of water management grid featured by system & mechanism construction and systemization of regulation decision-making. It is the integrated platform and comprehensive carrier for water conservancy practices. Currently, there still is dispute over engineering construction idea of smart water grid which, however, represents the future development trend of water management and is increasingly emphasized. The paper, based on distinction of concept of water grid and water grid engineering, explains the concept of water grid intelligentization, actively probes into construction idea of Smart water grid project in our country and presents scientific problems to be solved as well as core technologies to be mastered for smart water grid construction.

Potential of 3-D tissue constructs engineered from bovine chondrocytes / silk fibroin-chitosan for in vitro cartilage tissue engineering

PubMed Central

Bhardwaj, Nandana; Nguyen, Quynhhoa T; Chen, Albert C; Kaplan, David L.; Sah, Robert L; Kundu, Subhas C

2011-01-01

The use of cell-scaffold constructs is a promising tissue engineering approach to repair cartilage defects and to study cartilaginous tissue formation. In this study, silk fibroin/chitosan blended scaffolds were fabricated and studied for cartilage tissue engineering. Silk fibroin served as a substrate for cell adhesion and proliferation while chitosan has a structure similar to that of glycosaminoglycans, and shows promise for cartilage repair. We compared the formation of cartilaginous tissue in silk fibroin/chitosan blended scaffolds seeded with bovine chondrocytes and cultured in vitro for 2 weeks. The constructs were analyzed for cell viability, histology, extracellular matrix components glycosaminoglycan and collagen types I and II, and biomechanical properties. Silk fibroin/chitosan scaffolds supported cell attachment and growth, and chondrogenic phenotype as indicated by Alcian Blue histochemistry and relative expression of type II versus type I collagen. Glycosaminoglycan and collagen accumulated in all the scaffolds and was highest in the silk fibroin/chitosan (1:1) blended scaffolds. Static and dynamic stiffness at high frequencies was higher in cell-seeded constructs than non-seeded controls. The results suggest that silk/chitosan scaffolds may be a useful alternative to synthetic cell scaffolds for cartilage tissue engineering. PMID:21601277

The materials used in bone tissue engineering

NASA Astrophysics Data System (ADS)

Tereshchenko, V. P.; Kirilova, I. A.; Sadovoy, M. A.; Larionov, P. M.

2015-11-01

Bone tissue engineering looking for an alternative solution to the problem of skeletal injuries. The method is based on the creation of tissue engineered bone tissue equivalent with stem cells, osteogenic factors, and scaffolds - the carriers of these cells. For production of tissue engineered bone equivalent is advisable to create scaffolds similar in composition to natural extracellular matrix of the bone. This will provide optimal conditions for the cells, and produce favorable physico-mechanical properties of the final construction. This review article gives an analysis of the most promising materials for the manufacture of cell scaffolds. Biodegradable synthetic polymers are the basis for the scaffold, but it alone cannot provide adequate physical and mechanical properties of the construction, and favorable conditions for the cells. Addition of natural polymers improves the strength characteristics and bioactivity of constructions. Of the inorganic compounds, to create cell scaffolds the most widely used calcium phosphates, which give the structure adequate stiffness and significantly increase its osteoinductive capacity. Signaling molecules do not affect the physico-mechanical properties of the scaffold, but beneficial effect is on the processes of adhesion, proliferation and differentiation of cells. Biodegradation of the materials will help to fulfill the main task of bone tissue engineering - the ability to replace synthetic construct by natural tissues that will restore the original anatomical integrity of the bone.

Tissue Engineering Whole Bones Through Endochondral Ossification: Regenerating the Distal Phalanx.

PubMed

Sheehy, Eamon J; Mesallati, Tariq; Kelly, Lara; Vinardell, Tatiana; Buckley, Conor T; Kelly, Daniel J

2015-01-01

Novel strategies are urgently required to facilitate regeneration of entire bones lost due to trauma or disease. In this study, we present a novel framework for the regeneration of whole bones by tissue engineering anatomically shaped hypertrophic cartilaginous grafts in vitro that subsequently drive endochondral bone formation in vivo. To realize this, we first fabricated molds from digitized images to generate mesenchymal stem cell-laden alginate hydrogels in the shape of different bones (the temporomandibular joint [TMJ] condyle and the distal phalanx). These constructs could be stimulated in vitro to generate anatomically shaped hypertrophic cartilaginous tissues that had begun to calcify around their periphery. Constructs were then formed into the shape of the distal phalanx to create the hypertrophic precursor of the osseous component of an engineered long bone. A layer of cartilage engineered through self-assembly of chondrocytes served as the articular surface of these constructs. Following chondrogenic priming and subcutaneous implantation, the hypertrophic phase of the engineered phalanx underwent endochondral ossification, leading to the generation of a vascularized bone integrated with a covering layer of stable articular cartilage. Furthermore, spatial bone deposition within the construct could be modulated by altering the architecture of the osseous component before implantation. These findings open up new horizons to whole limb regeneration by recapitulating key aspects of normal bone development.

An Analog Computer for Electronic Engineering Education

ERIC Educational Resources Information Center

Fitch, A. L.; Iu, H. H. C.; Lu, D. D. C.

2011-01-01

This paper describes a compact analog computer and proposes its use in electronic engineering teaching laboratories to develop student understanding of applications in analog electronics, electronic components, engineering mathematics, control engineering, safe laboratory and workshop practices, circuit construction, testing, and maintenance. The…

23 CFR 627.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-04-01

... HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS VALUE ENGINEERING... construction. Value Engineering (VE) analysis. The systematic process of reviewing and assessing a project by a...; and (3) Reducing the time to develop and deliver the project. Value Engineering (VE) Job Plan. A...

23 CFR 627.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-04-01

... HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS VALUE ENGINEERING... construction. Value Engineering (VE) analysis. The systematic process of reviewing and assessing a project by a...; and (3) Reducing the time to develop and deliver the project. Value Engineering (VE) Job Plan. A...

Marine Engine-Exhaust Emissions Test Cell

DOT National Transportation Integrated Search

1974-11-01

A marine engine exhaust emissions test cell for boat-size diesel engines (approx. 200 hp) and outboard engines was constructed as part of a project sponsored by the United States Coast Guard for the monitoring and control of emissions from marine sou...

48 CFR 936.609-3 - Work oversight in architect-engineer contracts.

Code of Federal Regulations, 2012 CFR

2012-10-01

... architect-engineer contracts. 936.609-3 Section 936.609-3 Federal Acquisition Regulations System DEPARTMENT OF ENERGY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 936.609-3 Work oversight in architect-engineer contracts. In addition to the clause at 48...

48 CFR 936.609-3 - Work oversight in architect-engineer contracts.

Code of Federal Regulations, 2014 CFR

2014-10-01

... architect-engineer contracts. 936.609-3 Section 936.609-3 Federal Acquisition Regulations System DEPARTMENT OF ENERGY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 936.609-3 Work oversight in architect-engineer contracts. In addition to the clause at 48...

48 CFR 936.609-3 - Work oversight in architect-engineer contracts.

Code of Federal Regulations, 2013 CFR

2013-10-01

... architect-engineer contracts. 936.609-3 Section 936.609-3 Federal Acquisition Regulations System DEPARTMENT OF ENERGY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 936.609-3 Work oversight in architect-engineer contracts. In addition to the clause at 48...

48 CFR 936.609-3 - Work oversight in architect-engineer contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... architect-engineer contracts. 936.609-3 Section 936.609-3 Federal Acquisition Regulations System DEPARTMENT OF ENERGY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 936.609-3 Work oversight in architect-engineer contracts. In addition to the clause at 48...

48 CFR 936.609-3 - Work oversight in architect-engineer contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... architect-engineer contracts. 936.609-3 Section 936.609-3 Federal Acquisition Regulations System DEPARTMENT OF ENERGY SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 936.609-3 Work oversight in architect-engineer contracts. In addition to the clause at 48...

Forecasting Construction Cost Index based on visibility graph: A network approach

NASA Astrophysics Data System (ADS)

Zhang, Rong; Ashuri, Baabak; Shyr, Yu; Deng, Yong

2018-03-01

Engineering News-Record (ENR), a professional magazine in the field of global construction engineering, publishes Construction Cost Index (CCI) every month. Cost estimators and contractors assess projects, arrange budgets and prepare bids by forecasting CCI. However, fluctuations and uncertainties of CCI cause irrational estimations now and then. This paper aims at achieving more accurate predictions of CCI based on a network approach in which time series is firstly converted into a visibility graph and future values are forecasted relied on link prediction. According to the experimental results, the proposed method shows satisfactory performance since the error measures are acceptable. Compared with other methods, the proposed method is easier to implement and is able to forecast CCI with less errors. It is convinced that the proposed method is efficient to provide considerably accurate CCI predictions, which will make contributions to the construction engineering by assisting individuals and organizations in reducing costs and making project schedules.

Virtually Out of This World!

NASA Technical Reports Server (NTRS)

2002-01-01

Ames Research Center granted Reality Capture Technologies (RCT), Inc., a license to further develop NASA's Mars Map software platform. The company incorporated NASA#s innovation into software that uses the Virtual Plant Model (VPM)(TM) to structure, modify, and implement the construction sites of industrial facilities, as well as develop, validate, and train operators on procedures. The VPM orchestrates the exchange of information between engineering, production, and business transaction systems. This enables users to simulate, control, and optimize work processes while increasing the reliability of critical business decisions. Engineers can complete the construction process and test various aspects of it in virtual reality before building the actual structure. With virtual access to and simulation of the construction site, project personnel can manage, access control, and respond to changes on complex constructions more effectively. Engineers can also create operating procedures, training, and documentation. Virtual Plant Model(TM) is a trademark of Reality Capture Technologies, Inc.

Engineering of a complex bone tissue model with endothelialised channels and capillary-like networks.

PubMed

Klotz, B J; Lim, K S; Chang, Y X; Soliman, B G; Pennings, I; Melchels, F P W; Woodfield, T B F; Rosenberg, A J; Malda, J; Gawlitta, D

2018-05-30

In engineering of tissue analogues, upscaling to clinically-relevant sized constructs remains a significant challenge. The successful integration of a vascular network throughout the engineered tissue is anticipated to overcome the lack of nutrient and oxygen supply to residing cells. This work aimed at developing a multiscale bone-tissue-specific vascularisation strategy. Engineering pre-vascularised bone leads to biological and fabrication dilemmas. To fabricate channels endowed with an endothelium and suitable for osteogenesis, rather stiff materials are preferable, while capillarisation requires soft matrices. To overcome this challenge, gelatine-methacryloyl hydrogels were tailored by changing the degree of functionalisation to allow for cell spreading within the hydrogel, while still enabling endothelialisation on the hydrogel surface. An additional challenge was the combination of the multiple required cell-types within one biomaterial, sharing the same culture medium. Consequently, a new medium composition was investigated that simultaneously allowed for endothelialisation, capillarisation and osteogenesis. Integrated multipotent mesenchymal stromal cells, which give rise to pericyte-like and osteogenic cells, and endothelial-colony-forming cells (ECFCs) which form capillaries and endothelium, were used. Based on the aforementioned optimisation, a construct of 8 × 8 × 3 mm, with a central channel of 600 µm in diameter, was engineered. In this construct, ECFCs covered the channel with endothelium and osteogenic cells resided in the hydrogel, adjacent to self-assembled capillary-like networks. This study showed the promise of engineering complex tissue constructs by means of human primary cells, paving the way for scaling-up and finally overcoming the challenge of engineering vascularised tissues.

A systems-level approach for metabolic engineering of yeast cell factories.

PubMed

Kim, Il-Kwon; Roldão, António; Siewers, Verena; Nielsen, Jens

2012-03-01

The generation of novel yeast cell factories for production of high-value industrial biotechnological products relies on three metabolic engineering principles: design, construction, and analysis. In the last two decades, strong efforts have been put on developing faster and more efficient strategies and/or technologies for each one of these principles. For design and construction, three major strategies are described in this review: (1) rational metabolic engineering; (2) inverse metabolic engineering; and (3) evolutionary strategies. Independent of the selected strategy, the process of designing yeast strains involves five decision points: (1) choice of product, (2) choice of chassis, (3) identification of target genes, (4) regulating the expression level of target genes, and (5) network balancing of the target genes. At the construction level, several molecular biology tools have been developed through the concept of synthetic biology and applied for the generation of novel, engineered yeast strains. For comprehensive and quantitative analysis of constructed strains, systems biology tools are commonly used and using a multi-omics approach. Key information about the biological system can be revealed, for example, identification of genetic regulatory mechanisms and competitive pathways, thereby assisting the in silico design of metabolic engineering strategies for improving strain performance. Examples on how systems and synthetic biology brought yeast metabolic engineering closer to industrial biotechnology are described in this review, and these examples should demonstrate the potential of a systems-level approach for fast and efficient generation of yeast cell factories. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Proteomic differences between native and tissue‐engineered tendon and ligament

PubMed Central

Tew, Simon R.; Peffers, Mandy; Canty‐Laird, Elizabeth G.; Comerford, Eithne

2016-01-01

Tendons and ligaments (T/Ls) play key roles in the musculoskeletal system, but they are susceptible to traumatic or age‐related rupture, leading to severe morbidity as well as increased susceptibility to degenerative joint diseases such as osteoarthritis. Tissue engineering represents an attractive therapeutic approach to treating T/L injury but it is hampered by our poor understanding of the defining characteristics of the two tissues. The present study aimed to determine differences in the proteomic profile between native T/Ls and tissue engineered (TE) T/L constructs. The canine long digital extensor tendon and anterior cruciate ligament were analyzed along with 3D TE fibrin‐based constructs created from their cells. Native tendon and ligament differed in their content of key structural proteins, with the ligament being more abundant in fibrocartilaginous proteins. 3D T/L TE constructs contained less extracellular matrix (ECM) proteins and had a greater proportion of cellular‐associated proteins than native tissue, corresponding to their low collagen and high DNA content. Constructs were able to recapitulate native T/L tissue characteristics particularly with regard to ECM proteins. However, 3D T/L TE constructs had similar ECM and cellular protein compositions indicating that cell source may not be an important factor for T/L tissue engineering. PMID:27080496

Treatment of CHP in LEED® for Building Design and Construction: New Construction and Major Renovations

EPA Pesticide Factsheets

This factsheet introduces CHP and its benefits to architects and engineers, and summarizes how CHP is treated under the LEED® for Building Design and Construction: New Construction and Major Renovations (LEED BD+C: New Construction) rating system.

Computer-Aided Structural Engineering (CASE) Project: State of the Art on Expert Systems Applications in Design, Construction and Maintenance of Structures

DTIC Science & Technology

1989-09-01

OGT, F1EPQRTJTL4, W" - 3^ n"r-- n *ON EXPERT SYSTEMS IN DESIGN, CONSTRUCTION AND’, IWAJNTENANCE-OF STRUCTURES Arockiasamy, Sunghoon Lee Clepartrhent...based expert system applications in the areas of structural design, design standards, and construction planning. This study will aid in the development...of a comprehensive expert system for tvical hydraulic structures. Funding for this report was provided by the US Army Engineer Waterways Experiment

Environmental Assessment for Construction and Repair of Fuel Storage and Offloading Facilities at Kirtland Air Force Base

DTIC Science & Technology

2005-09-01

G Ot-T GOO) D. BRENT WILSON, P.E. Base Civil Engineer Kirtland Air Force Base Kirtland AFB Fuel Storage and Ofjloading Facilities Construction...September 2005 A-1 3 77 MSG/CEVQ DEPARTMENT OF THE AIR FORCE 3 77th Civil Engineer Division (AFMC) 2050 Wyoming Blvd SE, Suite 120 Kirtland AFB NM...FINAL FINDING OF NO SIGNIFICANT IMPACT FOR THE FOR CONSTRUCTION AND REP AIR OF FUEL STORAGE AND OFFLOADING FACILITIES AT KIRTLAND AIR FORCE

Building information modelling (BIM) after ten years: Malaysian construction players’ perception of BIM

NASA Astrophysics Data System (ADS)

Latiffi, A. Ahmad; Brahim, J.; Fathi, M. S.

2017-08-01

Building Information Modelling (BIM) concept has expanded widely in many countries for more than a decade with its role of improving current practices in construction projects. However, the understanding of BIM differs among construction players, depending on how construction players utilize the concept in their projects. Therefore, this paper aims to explore the understanding of BIM concept among construction players in the Malaysian construction industry. A literature review on BIM concept and semi-structured interviews with construction players in BIM such as client, civil and structural (C&S) engineer and mechanical and electrical (M&E) engineer, quantity surveyor (QS), contractor, facilities manager and BIM consultant have been conducted in order to achieve this study’s the aim. The results show that the understanding of BIM concept among the construction players is limited to BIM as a process and technology. It is important for the construction players to improve their understanding of BIM as it can be used to enhance performance and productivity of construction projects.

A Guide for Using Mechanical Stimulation to Enhance Tissue-Engineered Articular Cartilage Properties.

PubMed

Salinas, Evelia Y; Hu, Jerry C; Athanasiou, Kyriacos

2018-04-26

The use of tissue-engineered articular cartilage (TEAC) constructs has the potential to become a powerful treatment option for cartilage lesions resulting from trauma or early stages of pathology. Although fundamental tissue-engineering strategies based on the use of scaffolds, cells, and signals have been developed, techniques that lead to biomimetic AC constructs that can be translated to in vivo use are yet to be fully confirmed. Mechanical stimulation during tissue culture can be an effective strategy to enhance the mechanical, structural, and cellular properties of tissue-engineered constructs toward mimicking those of native AC. This review focuses on the use of mechanical stimulation to attain and enhance the properties of AC constructs needed to translate these implants to the clinic. In vivo, mechanical loading at maximal and supramaximal physiological levels has been shown to be detrimental to AC through the development of degenerative changes. In contrast, multiple studies have revealed that during culture, mechanical stimulation within narrow ranges of magnitude and duration can produce anisotropic, mechanically robust AC constructs with high cellular viability. Significant progress has been made in evaluating a variety of mechanical stimulation techniques on TEAC, either alone or in combination with other stimuli. These advancements include determining and optimizing efficacious loading parameters (e.g., duration and frequency) to yield improvements in construct design criteria, such as collagen II content, compressive stiffness, cell viability, and fiber organization. With the advancement of mechanical stimulation as a potent strategy in AC tissue engineering, a compendium detailing the results achievable by various stimulus regimens would be of great use for researchers in academia and industry. The objective is to list the qualitative and quantitative effects that can be attained when direct compression, hydrostatic pressure, shear, and tensile loading are used to tissue-engineer AC. Our goal is to provide a practical guide to their use and optimization of loading parameters. For each loading condition, we will also present and discuss benefits and limitations of bioreactor configurations that have been used. The intent is for this review to serve as a reference for including mechanical stimulation strategies as part of AC construct culture regimens.

Building information models for astronomy projects

NASA Astrophysics Data System (ADS)

Ariño, Javier; Murga, Gaizka; Campo, Ramón; Eletxigerra, Iñigo; Ampuero, Pedro

2012-09-01

A Building Information Model is a digital representation of physical and functional characteristics of a building. BIMs represent the geometrical characteristics of the Building, but also properties like bills of quantities, definition of COTS components, status of material in the different stages of the project, project economic data, etc. The BIM methodology, which is well established in the Architecture Engineering and Construction (AEC) domain for conventional buildings, has been brought one step forward in its application for Astronomical/Scientific facilities. In these facilities steel/concrete structures have high dynamic and seismic requirements, M&E installations are complex and there is a large amount of special equipment and mechanisms involved as a fundamental part of the facility. The detail design definition is typically implemented by different design teams in specialized design software packages. In order to allow the coordinated work of different engineering teams, the overall model, and its associated engineering database, is progressively integrated using a coordination and roaming software which can be used before starting construction phase for checking interferences, planning the construction sequence, studying maintenance operation, reporting to the project office, etc. This integrated design & construction approach will allow to efficiently plan construction sequence (4D). This is a powerful tool to study and analyze in detail alternative construction sequences and ideally coordinate the work of different construction teams. In addition engineering, construction and operational database can be linked to the virtual model (6D), what gives to the end users a invaluable tool for the lifecycle management, as all the facility information can be easily accessed, added or replaced. This paper presents the BIM methodology as implemented by IDOM with the E-ELT and ATST Enclosures as application examples.

48 CFR 836.603 - Collecting data on and appraising firms qualifications.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Construction and Facilities Management, for Central Office; the Director, Office of Construction Management... VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect...

48 CFR 836.603 - Collecting data on and appraising firms qualifications.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Construction and Facilities Management, for Central Office; the Director, Office of Construction Management... VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect...

48 CFR 836.603 - Collecting data on and appraising firms qualifications.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Construction and Facilities Management, for Central Office; the Director, Office of Construction Management... VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect...

48 CFR 836.603 - Collecting data on and appraising firms qualifications.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Construction and Facilities Management, for Central Office; the Director, Office of Construction Management... VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect...

48 CFR 836.603 - Collecting data on and appraising firms qualifications.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Construction and Facilities Management, for Central Office; the Director, Office of Construction Management... VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect...

Prefabrication of 3D Cartilage Contructs: Towards a Tissue Engineered Auricle – A Model Tested in Rabbits

PubMed Central

von Bomhard, Achim; Veit, Johannes; Bermueller, Christian; Rotter, Nicole; Staudenmaier, Rainer; Storck, Katharina; The, Hoang Nguyen

2013-01-01

The reconstruction of an auricle for congenital deformity or following trauma remains one of the greatest challenges in reconstructive surgery. Tissue-engineered (TE) three-dimensional (3D) cartilage constructs have proven to be a promising option, but problems remain with regard to cell vitality in large cell constructs. The supply of nutrients and oxygen is limited because cultured cartilage is not vascular integrated due to missing perichondrium. The consequence is necrosis and thus a loss of form stability. The micro-surgical implantation of an arteriovenous loop represents a reliable technology for neovascularization, and thus vascular integration, of three-dimensional (3D) cultivated cell constructs. Auricular cartilage biopsies were obtained from 15 rabbits and seeded in 3D scaffolds made from polycaprolactone-based polyurethane in the shape and size of a human auricle. These cartilage cell constructs were implanted subcutaneously into a skin flap (15×8 cm) and neovascularized by means of vascular loops implanted micro-surgically. They were then totally enhanced as 3D tissue and freely re-implanted in-situ through microsurgery. Neovascularization in the prefabricated flap and cultured cartilage construct was analyzed by microangiography. After explantation, the specimens were examined by histological and immunohistochemical methods. Cultivated 3D cartilage cell constructs with implanted vascular pedicle promoted the formation of engineered cartilaginous tissue within the scaffold in vivo. The auricles contained cartilage-specific extracellular matrix (ECM) components, such as GAGs and collagen even in the center oft the constructs. In contrast, in cultivated 3D cartilage cell constructs without vascular pedicle, ECM distribution was only detectable on the surface compared to constructs with vascular pedicle. We demonstrated, that the 3D flaps could be freely transplanted. On a microangiographic level it was evident that all the skin flaps and the implanted cultivated constructs were well neovascularized. The presented method is suggested as a promising alternative towards clinical application of engineered cartilaginous tissue for plastic and reconstructive surgery. PMID:23951215