bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generation of Foxo3‐targeted Mice by Injection of mRNAs Encoding Transcription Activator‐like Effector Nucleases (TALENs) into Zygotes
Authors: Zhu P , Liu Q , Liu S , Su X , Feng W , Lei X , Liu J , Cui K , Huang B , Shi D 
Published: March 2015

ContentsIn this study, for exploring the mechanism of forkhead box O3(Foxo3) participating in regulation of the activation of primordial oocytes, Foxo3‐targeted mice were generated by injection of mRNAs encoding transcription activator‐like effector nucleases (TALENs) into mouse zygotes. The TALEN sites were designed with high conservative homologous region among pig, bovine, buffalo and mouse by commercial bio‐companies. The TALENs mutagenic non‐homologous end‐joining (NHEJ) repair activity were determined to be 31.3% in human embryonic kidney 293T (HEK‐293T) cells by dual luciferase reporter assay system. Then, we firstly injected TALEN‐mRNAs into the cytoplasm of mouse zygotes by micromanipulation, and four of 48 mouse blastocysts were identified as mutation by sequencing. Subsequently, by the method of TALEN‐mRNAs injected into the zygotes with pronucleus micromanipulation technique, we obtained seven Foxo3 mutants of 20 FVB/NJ backgrounds mice which were Foxo3‐independent alleles with frameshift and deletion mutations. It was very interesting that all seven were heterozygous mutants (Foxo3−/+), and the gene mutagenesis rates of the mice reached 35%. The five Foxo3 mutant females were all infertile in the following 6 months after birth. The histological examination results showed that there were rare primordial follicles and primary follicles in the ovary of Foxo3 mutant compared to that of wide‐type female mice. Moreover, one of two mutant males was subfertile and another was fertile normally. Those results suggested that the mutant of Foxo3 severely affected the fertile ability of female and perhaps male in some degree; furthermore, an even more efficient TALENs‐based gene mutation method has been established to be poised to revolutionize the study of mouse and other species genetics.
Prediction of Arteriovenous Fistula Dysfunction: Can it be Taught?
Authors: Rosenberg Joel E. , Yevzlin Alexander S. , Chan Micah R. , Valliant Amanda M. , Astor Brad C. 
Published: March 2015

AbstractPhysical examination (PE) is an excellent means of predicting arteriovenous fistula (AVF) dysfunction. Although quick and inexpensive,PEis seldom used as a tool to assess stenosis by general nephrologists, dialysis nurses, and dialysis technicians. Previous studies have demonstrated thatPEcan be taught to interventional specialists, but the perception remains that it is too complex to be performed by other health care professionals. We hypothesized that the physical exam can be taught to a nonmedical professional, and that, with time, it would be comparable to the physical exam performed by a full‐time interventional specialist. An undergraduate student and an interventional specialist (MD) examinedAVFfor dysfunction in a tertiary care hospital over a 6‐month period.PEwas performed on patients who were suspected of having dialysis access dysfunction and were referred for angiography and intervention (n = 49). Physical exam findings were categorized blindly by each examiner into four categories of lesion location: inflow, outflow, both, or neither. Data were privately recorded and compared to the gold standard of angiographic results. Potential confounding variables, including age, gender, diabetic status, and location ofAVFwere recorded. Weighted Cohen's kappa value was used as a measurement of the level of agreement beyond chance between the diagnoses made by physical exam and angiography. The full‐time interventional specialist demonstrated correct prediction of lesion location of 89.8% (kappa = 0.850), while the undergraduate student had a correct prediction of 77.6% (kappa = 0.625). The student's performance, however, differed significantly over time. The student correctly predicted the location of the lesion in 6 (42.9%) of the first 14 patients (kappa = 0.082), compared to 32 (91.4%) of the last 35 patients (kappa = 0.855). We suggest that physical exam of AVF can be taught to a nonmedical professional in a short duration of time and the predictive value of the exam can be similar to that of an interventional specialist.
Optimizing the Performance of Compressed Air Energy Storage (CAES) Compressor and Turbine Trains
Authors: Marinacci Daniel J. , Bumgarner James M. , Bonk Joseph S. , Schainker Robert B. 
Published: March 2015

This paper is a result of work done by the Westinghouse Electric Corporation on a $1.8 million, 3 1/2 year study funded by DOE and EPRI.
The potential future market for Compressed Air Energy Storage (CAES) system is substantial. The savings realized by utilizing CAES power plants can be very attractive with the proper generation mix.
The thermodynamic parametric performance studies that were conducted to screen the various aquifer charging and discharging cycles are discussed. Equations are presented to directly calculate the optimum (minimum required total compressor work and air cooler heat rejection) intercooler(s) location for a compressor train utilizing one and two inter-coolers. An equation is also presented which directly determines the reheat combustor location required to maximize the turbine train output. A discussion is included why the performance of CAES power cycles must be optimized by considering the total power production energy costs not on a basis of maximum turbine output power or heat rate.
Hardware and economic considerations which lead to CAES LP turbomachinery component standardization are discussed. Such standardization allows a manufacturer to economically adapt its CAES turbomachinery to a range of different air storage pressures.
Mathematical Model of Transient Temperature Distribution and Thermal Stresses in Large Steam Turbine Rotors
Authors: Sasiadek J. , Kwok C. K. 
Published: March 2015

The most important problems encountered in power plants are related to cold start-up, hot start-up, daily and seasonal variation in load. These problems are specially critical for high power units above 525°C and 10.5 MN/m2. As a result of higher thermal capacity of the thicker components in larger power units, the temperature gradient and thermal stresses assumed much higher values. It is, therefore, particularly important during transient operation conditions to know the temperature distribution and thermal stresses of rotors. One of the most common concerns is how fast can a turbine be started without significant damage. If the turbine is loaded very rapidly, high temperature gradient and excessive thermal stresses can easily damage the machine.
A concept was developed whereby an on-line computer was used to control the start-up and load variation operations of the turbine. The feasibility of such concept depends upon the knowledge of the instantaneous temperature distribution and thermal stresses of the turbine rotors. This paper presents a 2-D mathematical model of the transient temperature distribution as well as thermal stresses of the rotor. The mathematical model was simulated in the computer and ADI method was used for the solution of the governing equations. Discussions will be made of the procedure of coupling this mathematical model with on-line computer for optimum control of start-up and load variation schedule.
Temperature and Dilution Effects in Soot Mass Concentration Measurements
Authors: Clark J. A. , Moser D. W. , Best W. D. , Thompson N. A. 
Published: March 2015

Measurements are made of soot mass concentration in a luminous, liquid fuel spray, diffusion flame at atmospheric pressure. Intrusive sampling probes are used to study the effects of sampling rate, cooling, nitrogen-dilution ratio, and tip geometry on the mass of soot particles deposited on filters. Probe diameters have been kept small to minimize disturbance to the flow-field.
Relative soot concentrations are observed to be lowest for uncooled probes, higher for water-cooled probes and still higher for probes with both water cooling and nitrogen injection. Furthermore, soot concentration steadily rises as the nitrogen/sample dilution ratio is increased from zero to as high as 1.5. Sampling rate has little effect on soot concentrations under most, but not all, sampling conditions.
Performance Testing in Oxygen of a High-Pressure, High-Volume Oxygen Compressor
Authors: Tessier M. J. , Granger R. A. 
Published: March 2015

In connection with the Coal Gasification Program of the U.S. Department of Energy, a need was identified for a high-pressure, high-volume oxygen compressor. At the time, the highest steady operating pressure available from commercial-sized turbocompressors was about 65 bar (950 psia), which was being used in the partial oxidation process for ammonia or methanol synthesis. For advanced coal conversion plants, compressors operating at 115 bar (1667 psia) would be needed.
The U.S. Department of Energy (DOE) entered into an agreement with the West German firm of Mannesmann Demag, AG, to develop a high-pressure oxygen compressor. Mannesmann Demag designed and fabricated a third casing centrifugal compressor (to be used in a train with available compressors) having a nominal inlet pressure of 65 bar (950 psia) and a nominal discharge pressure of 115 bar (1667 psia). In exchange, the U.S. DOE agreed to fund the modification and operation of a NASA-owned test facility for testing the compressor. The facility, CTL-V, was modified and operated by the Rocketdyne Division of Rockwell International. Test management and reporting was carried out by DOE’s Energy Technology Engineering Center (ETEC), operated by Rockwell International’s Energy Systems Group.
This paper presents a brief description of the compressor test article and test facility. The test program, test results, and analysis are presented in greater detail. The scope of the test program included low- and high-pressure nitrogen shakedown tests, oxygen performance and steady-state tests, and oxygen maximum suction pressure tests.
The facility is unique because it is the only one of its kind nationally that can provide the power to drive the compressor and that has liquid oxygen/liquid nitrogen capability (the facility is utilized for development and testing of rocket engine turbopumps). Also, testing and data acquisition, reduction, and analysis were performed in a facility that normally runs tests of few minutes duration (for rocket engine components) but that had to be converted to run endurance tests lasting several hundred hours.
A Variable-Geometry Combustor Used to Study Primary and Secondary Zone Stoichiometry
Authors: Briehl Daniel , Schultz Donald F. , Ehlers Robert C. 
Published: March 2015

A combustion program is underway to evaluate fuel quality effects on gas turbine combustors. A rich-lean variable geometry combustor design was chosen to evaluate fuel quality effects over a wide range of primary and secondary zone equivalence ratios at simulated engine operating conditions. The first task of this effort, was to evaluate the performance of the variable geometry combustor. The combustor incorporates three stations of variable geometry to control primary and secondary zone equivalence ratio and overall pressure loss. Geometry changes could be made while a test was in progress through the use of remote control actuators. The primary zone liner was water cooled to eliminate the concern of liner durability.
Emissions and performance data were obtained at simulated engine conditions of 80 percent and full power. Inlet air temperature varied from 611 to 665 K, inlet total pressure varied from 1.02 to 1.24 MPa, reference velocity was 18.0 m/sec and exhaust gas temperature was a constant 1400 K.
Pressurized Fluidized-Bed Combustion: A Status Report
Authors: Scott R. L. , Hoy H. R. , Roberts A. E. 
Published: March 2015

The first ever pressurized fluidized-bed combustor (PFBC) came into operation at the laboratories of the British Coal Utilization Research Laboratory at Leatherhead in 1969. This operated at pressures up to 6 atmospheres and ultimately had a thermal input of 4.5 MW. In the ensuing years, six other laboratory-scale combustors with thermal inputs ranging from 0.4 MW to about 2.4 MW and with working pressures up to 20 atmospheres came into operation. Scale up of the technology began in 1980.
Comprehensive data on combustion, hot gas cleanup and environmental aspects of the technology have been accumulated and design studies have shown that combined-cycle power plant based on PFBC have the potential to provide electric power at lower busbar costs than competing advanced power generating technologies.
This paper provides an overview on the development of the technology, the technical advances made, and those in the pipeline aimed at making the system even more attractive.
Cogeneration - Interactions of Gas Turbine, Boiler and Steam Turbine
Authors: Foster-Pegg R. W. 
Published: March 2015

A gas turbine cogeneration plant produces power and process steam. Under the PURPA law, surplus electric power can be sold to the local utility. Since process steam generally cannot be exported, it is better to have an excess of power than an excess of steam.
Because of low rates offered for surplus power, or for other possible reasons, an owner may not wish to sell power, so it may be necessary to operate at a power-to-steam ratio that does not match the outputs of a gas turbine with a simple heat recovery boiler. If more steam is needed, supplementary firing may be included in the heat recovery boiler.
If the need is for more power, a back pressure steam turbine can be included. This reduces the steam output by requiring higher steam pressure. Further power increase and steam reduction can be obtained with a condensing steam turbine. If neither the full steam output nor additional power is required, capital cost can be reduced by inclusion of a smaller, less-efficient heat recovery boiler.
This paper compares these means of adjusting the power and steam outputs of a gas turbine cogeneration system to obtain the most cost effective system.
Flow Instability in Low-Pressure Turbine Blade Passages
Authors: Whirlow D. K. , McCloskey T. H. , Davids J. , Chen S. , Kadambi J. R. , Farn C. L. S. 
Published: March 2015

The unsteady interaction among shocks, spontaneous condensation and boundary layers were measured in a cascade of tip section turbine blades with steam conditions similar to those that would be experienced by the blade under actual field conditions.
Test conditions covered the Mach number range of 1.0 to 1.4, based upon isentropic exit conditions. Inlet temperature conditions were such as to provide fully dry runs, runs with shock and condensation being approximately coincident, and runs with the condensation occurring upstream of the shock.
Unsteady pressure data were provided by six miniature pressure transducers embedded in the suction surface of one of the blades in the region of the impingement of the trailing edge shock from the adjacent blade.
Spatial integration of the individual transducer signals provided fluctuating forces over the region measured.
Unsteady forces were generally low but the nature and level of the fluctuating forces were different near a Mach number of 1.0, where several distinct spikes were present, and responses for some frequencies reached nearly one percent of the steady forces.
300 MW Combined-Cycle Plant With Integrated Coal Gasification
Authors: Kehlhofer Rolf H. 
Published: March 2015

In the past 15 years the combined-cycle (gas/steam turbine) power plant has come into its own in the power generation market. Today, approximately 30 000 MW of power are already installed or being built as combined-cycle units. Combined-cycle plants are therefore a proven technology, showing not only impressive thermal efficiency ratings of up to 50 percent in theory, but also proving them in practice and everyday operation (1) (2).
Combined-cycle installations can be used for many purposes. They range from power plants for power generation only, to cogeneration plants for district heating or combined cycles with maximum additional firing (3).
The main obstacle to further expansion of the combined cycle principle is its lack of fuel flexibility. To this day, gas turbines are still limited to gaseous or liquid fuels. This paper shows a viable way to add a cheap solid fuel, coal, to the list. The plant system in question is a 2 × 150 MW combined-cycle plant of BBC Brown Boveri with integrated coal gasification plant of British Gas/Lurgi. The main point of interest is that all the individual components of the power plant described in this paper have proven their worth commercially. It is therefore not a pilot plant but a viable commercial proposition.
A Gas Turbine Interactive Design System — TDSYS — for Advanced Gas Turbines
Authors: Sato T. , Aoki S. , Mori H. 
Published: March 2015

The characteristics and experiences of the gas turbine interactive design system, TDSYS, are described.
The design of high performance advanced gas turbines requires complex trade-off analyses for optimization and hence it is necessary to use a highly efficient and accurate computerised integrated design system to complete the laborious design jobs in a short time.
TDSYS is an interactive design system which makes extensive use of computer graphics and enables the designers to complete a gas turbine blade design systematically in a very short time.
TDSYS has been developed and continuously improved over a period of ten years. The system has been used for the complete and retrofit design of many gas turbines including Mitsubishi MW701 and AGTJ-100A which is a high efficiency reheat gas turbine now being developed under a Japanese national project.
In this paper, typical design samples of high temperature turbines are also presented.
Preliminary Engineering for a 50 MW Compressed Air Energy Storage Plant for Alabama Electric Cooperative, Inc.
Authors: Clausen B. R. , Nakhamkin M. , Swensen E. C. 
Published: March 2015

This paper presents preliminary engineering results for a 50 MW Compressed Air Energy Storage (CAES) plant for the Alabama Electric Cooperative, Inc. (AEC). The CAES plant would improve AEC’s power generation mix in two ways: (a) it would provide needed peaking/intermediate power (otherwise purchased) and (b) it would increase the load factor of economical baseload units.
The paper presents the following:
a. Comparative trade-off analysis of various conceptual arrangements with underground storage depths ranging between 1000 feet and 4000 feet. (The most economical concept is selected based on the consideration of economics of the overall plant including underground storage).
b. Engineering and cost data, performance data, construction schedule and environmental data for the selected CAES plant concept.
The results of this preliminary engineering effort prove that a CAES plant is a cost effective addition to AEC’s installed power generation plants.
Circulating Fluidized Bed Combustor Utilization With Compressed Air Energy Storage Plants
Authors: Nakhamkin Michael , Stange John R. , Duttenhoffer Richard , Pelini Robert , Schainker Robert B. 
Published: March 2015

This paper presents results of engineering of a Circulating Fluidized Bed Combustor (CFBC) for Compressed Air Energy Storage (CAES) application. This development allows eliminating the use of premium fuels thus resolving economic as well as institutional issues.
The paper summarizes the engineering, performance and cost data for a CFBC and presents comparative technical and economic analyses of a CAES plant with CFBC (burning coal) versus a conventional CAES plant (burning premium fuel).
Closed Circuit Steam Cooling in Gas Turbines
Authors: Alderson E. D. , Scheper G. W. , Cohn A. 
Published: March 2015

In the continuing effort to achieve better specific power and higher cycle efficiencies, gas turbine designers have through the years sought higher and higher firing temperatures. A large part of this gain in firing temperatures has been achieved through cooling the turbine nozzles and buckets. In almost all cases the coolant, usually air, is discharged into the gas path after performing its cooling function. This approach entails the double penalties of causing mixing losses and of producing a dilution of the hot gas stream by admixture of the lower temperature coolant.
This paper presents a new cooling concept, developed under a study contract for Electric Power Research Institute, wherein high pressure steam is used as the coolant in a closed circuit steam cooling (CCSC) system. This not only avoids the mixing and dilution losses in the gas turbine, but permits recovery of the heat picked up in the coolant by expansion in a steam turbine. With CCSC, Brayton-combined cycle thermal efficiencies of 54% are projected using current materials and technology. With development of specific technologies, an ultimate efficiency for the Brayton-combined cycle of 57% is foreseen. This paper also discusses the sensitivity of the cycle performance to the design parameters. Performance of this CCSC cycle is compared to that of an advanced air-cooled Brayton combined cycle.
An investigation into factors affecting the precision of CT radiation dose profile width measurements using radiochromic films
Authors: Li Baojun , Behrman Richard H. 
Published: March 2015

Purpose:To investigate the impact of x‐ray beam energy, exposure intensity, and flat‐bed scanner uniformity and spatial resolution on the precision of computed tomography (CT) beam width measurements using Gafchromic XR‐QA2 film and an off‐the‐shelf document scanner.Methods:Small strips of Gafchromic film were placed at isocenter in a CT scanner and exposed at various x‐ray beam energies (80–140 kVp), exposure levels (50–400 mA s), and nominal beam widths (1.25, 5, and 10 mm). The films were scanned in reflection mode on a Ricoh MP3501 flat‐bed document scanner using several spatial resolution settings (100 to 400 dpi) and at different locations on the scanner bed. Reflection measurements were captured in digital image files and radiation dose profiles generated by converting the image pixel values to air kerma through film calibration. Beam widths were characterized by full width at half maximum (FWHM) and full width at tenth maximum (FWTM) of dose profiles. Dependences of these parameters on the above factors were quantified in percentage change from the baselines.Results:The uncertainties in both FWHM and FWTM caused by varying beam energy, exposure level, and scanner uniformity were all within 4.5% and 7.6%, respectively. Increasing scanner spatial resolution significantly increased the uncertainty in both FWHM and FWTM, with FWTM affected by almost 8 times more than FWHM (48.7% vs 6.5%). When uncalibrated dose profiles were used, FWHM and FWTM were over‐estimated by 11.6% and 7.6%, respectively. Narrower beam width appeared more sensitive to the film calibration than the wider ones (R2 = 0.68 and 0.85 for FWHM and FWTM, respectively). The global and maximum local background variations of the document scanner were 1.2%. The intrinsic film nonuniformity for an unexposed film was 0.3%.Conclusions:Measurement of CT beam widths using Gafchromic XR‐QA2 films is robust against x‐ray energy, exposure level, and scanner uniformity. With proper film calibration and scanner resolution setting, it can provide adequate precision for meeting ACR and manufacturer's tolerances for the measurement of CT dose profiles.
Genome Sequence of Bivens Arm Virus, a Tibrovirus Belonging to the Species Tibrogargan virus (
Mononegavirales
:
Rhabdoviridae
)
Authors: Lauck Michael , Yú Shuǐqìng , Caì Yíngyún , Hensley Lisa E. , Chiu Charles Y. , O’Connor David H. , Kuhn Jens H. 
Published: March 2015

ABSTRACT

The new rhabdoviral genus
Tibrovirus
currently has two members, Coastal Plains virus and Tibrogargan virus. Here, we report the coding-complete genome sequence of a putative member of this genus, Bivens Arm virus. A genomic comparison reveals Bivens Arm virus to be closely related to, but distinct from, Tibrogargan virus.