WorldWideScience

Sample records for cell transit buses

  1. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2007-03-01

    This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

  2. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2010

    Science.gov (United States)

    2010-11-11

    This past year has been one of transition for the introduction of fuel cell transit buses. The existing generation of fuel cell buses from Van Hool and UTC Power has continued to operate in service at three transit agencies. At the same time, a new g...

  3. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2011

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.; Gikakis, C.

    2011-11-01

    This status report, fifth in a series of annual status reports from the U.S. Department of Energy's National Renewable Energy Laboratory (NREL), discusses the achievements and challenges of fuel cell propulsion for transit and summarizes the introduction of fuel cell transit buses in the United States. Progress this year includes an increase in the number of fuel cell electric buses (FCEBs), from 15 to 25, operating at eight transit agencies, as well as increased diversity of the fuel cell design options for transit buses. The report also provides an analysis of the combined results from fuel cell transit bus demonstrations evaluated by NREL with a focus on the most recent data through July 2011 including fuel cell power system reliability and durability; fuel economy; roadcall; and hydrogen fueling results. These evaluations cover 22 of the 25 FCEBs currently operating.

  4. Transit experience with hydrogen fueled hybrid electric buses

    International Nuclear Information System (INIS)

    Scott, P.B.; Mazaika, D.M.; Levin, J.; Edwards, T.

    2006-01-01

    Both AC Transit and SunLine Transit operate hybrid electric hydrogen fueled buses in their transit service. ACT presently operates three fuel cell buses in daily revenue service, and SunLine operates a fuel cell bus and a HHICE (Hybrid Hydrogen Internal Combustion Engine) bus. All these buses use similar electric drive train and electric accessories, although the detailed design differs notably between the fuel cell and the hybrid ICE buses. The fuel cell buses use a 120kW UTC fuel cell and a Van Hool Chassis, whereas the HHICE bus uses a turbocharged Ford engine which is capable of 140kW generator output in a New Flyer Chassis. The HHICE bus was the first in service, and has been subjected to both winter testing in Manitoba, Canada and summer testing in the Palm Springs, CA region. The winter testing included passenger sampling using questionnaires to ascertain passenger response. The fuel cell buses were introduced to service at the start of 2006. All five buses are in daily revenue service use. The paper will describe the buses and the experience of the transit properties in operating the buses. (author)

  5. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2010

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.; Gigakis, C.

    2010-11-01

    This status report, fourth in a series of annual status reports from the U.S. Department of Energy's National Renewable Energy Laboratory, summarizes progress and accomplishments from demonstrations of fuel cell transit buses in the United States. This year's assessment report provides the results from the fifth year of operation of five Van Hool, ISE, and UTC Power fuel cell buses operating at AC Transit, SunLine, and CTTRANSIT. The achievements and challenges of this bus design, implementation, and operating are presented, with a focus on the next steps for implementing larger numbers and new and different designs of fuel cell buses. The major positive result from nearly five years of operation is the dramatic increase in reliability experienced for the fuel cell power system.

  6. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2015

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gikakis, Christina [Federal Transit Administration, Washington, DC (United States)

    2015-12-11

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. Various stakeholders, including FCEB developers, transit agencies, and system integrators, have expressed the value of this annual status report, which provides a summary of results from evaluations performed by the National Renewable Energy Laboratory. The annual status report tracks the progress of the FCEB industry toward meeting technical targets, documents the lessons learned, and discusses the path forward for commercial viability of fuel cell technology for transit buses. The 2015 summary results primarily focus on the most recent year for each demonstration, from August 2014 through July 2015. The results for these buses account for more than 1,045,000 miles traveled and 83,000 hours of fuel cell power system operation. The primary results presented in the report are from two demonstrations of fuel-cell-dominant bus designs: the Zero Emission Bay Area Demonstration Group led by Alameda-Contra Costa Transit District (AC Transit) in California and the American Fuel Cell Bus Project at SunLine Transit Agency in California.

  7. To Evaluate Zero Emission Propulsion and Support Technology for Transit Buses

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Chandler; Leslie Eudy

    2006-11-01

    This report provides evaluation results for prototype fuel cell transit buses operating at Santa Clara Valley Transportation Authority (VTA) in San Jose, California, in partnership with the San Mateo County Transit District in San Carlos, California. VTA has been operating three fuel cell transit buses in extra revenue service since February 28, 2005. This report provides descriptions of the equipment used, early experiences, and evaluation results from the operation of the buses and the supporting hydrogen infrastructure from March 2005 through July 2006.

  8. Transit experience with hydrogen fueled hybrid electric buses

    Energy Technology Data Exchange (ETDEWEB)

    Scott, P.B.; Mazaika, D.M. [ISE Corp., Poway, CA (United States)

    2006-07-01

    Mass transit buses are ideal candidates for hydrogen implementation due to their capability of carrying 30 to 60 kg of hydrogen. ISE Corporation is a supplier of hydrogen fueled buses, including the first hybrid electric fuel cell bus which was commercialized in 2002, the hybrid electric fuel cell bus, and the hybrid hydrogen internal combustion engine (HHICE) bus which was commercialized in 2004. The configuration of a HHICE bus was illustrated with reference to its engine, control system, energy storage, generator, drive motor, inverter and accessories. Although these vehicles are expensive, the cost is amortized over a large base of hours used and passengers carried. The buses are operated primarily in urban areas where quiet and clean operation is needed the most. ISE has established a joint venture with Thor industries to develop a series of fuel cell buses equipped with a 60 kW PEM fuel cell. A schematic illustrating the energy flow in HHICE bus was also presented. It was shown that regenerative braking recovers the energy of motion. When using regenerative braking, most of the braking energy is saved in the battery. ISE drive systems convert 30 per cent or more of the bus energy to electrical energy to be used in later acceleration. Reduced fuel consumption also reduces the vehicle emissions. Testing of HHICE buses in both summer and winter operating conditions have shown that the range needs to be improved along with engine component reliability and durability. Fuel supply is also a major issue. A comparison with a fuel cell hybrid system was also presented. In the United States, more than 100,000 miles have been logged for the use of hydrogen hybrid buses, fuel cell buses and HHICE buses. The HHICE bus offers low capital cost, familiar technologies, but some NOx. CAT absorber technology offers the possibility of near zero emission capability. The fuel cell bus was found to be more fuel efficient, and can travel nearly twice as far per unit energy as

  9. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2016

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jeffers, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-11-01

    This report, published annually, summarizes the progress of fuel cell electric bus development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of results from evaluations performed by the National Renewable Energy Laboratory. Funding for this effort is provided by the U.S. Department of Energy's Fuel Cell Technologies Office within the Office of Energy Efficiency and Renewable Energy and by the U.S. Department of Transportation's Federal Transit Administration. The 2016 summary results primarily focus on the most recent year for each demonstration, from August 2015 through July 2016. The results for these buses account for more than 550,000 miles traveled and 59,500 hours of fuel cell power system operation. The primary results presented in the report are from three demonstrations of two different fuel-cell-dominant bus designs: Zero Emission Bay Area Demonstration Group led by Alameda-Contra Costa Transit District (AC Transit) in California; American Fuel Cell Bus Project at SunLine Transit Agency in California; and American Fuel Cell Bus Project at the University of California at Irvine.

  10. Massachusetts Fuel Cell Bus Project: Demonstrating a Total Transit Solution for Fuel Cell Electric Buses in Boston

    Energy Technology Data Exchange (ETDEWEB)

    2017-05-22

    The Federal Transit Administration's National Fuel Cell Bus Program focuses on developing commercially viable fuel cell bus technologies. Nuvera is leading the Massachusetts Fuel Cell Bus project to demonstrate a complete transit solution for fuel cell electric buses that includes one bus and an on-site hydrogen generation station for the Massachusetts Bay Transportation Authority (MBTA). A team consisting of ElDorado National, BAE Systems, and Ballard Power Systems built the fuel cell electric bus, and Nuvera is providing its PowerTap on-site hydrogen generator to provide fuel for the bus.

  11. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2017

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew B [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-11-21

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of results from evaluations performed by the National Renewable Energy Laboratory. This annual status report combines results from all FCEB demonstrations, tracks the progress of the FCEB industry toward meeting technical targets, documents the lessons learned, and discusses the path forward for commercial viability of fuel cell technology for transit buses. These data and analyses help provide needed information to guide future early-stage research and development. The 2017 summary results primarily focus on the most recent year for each demonstration, from August 2016 through July 2017. The primary results presented in the report are from five demonstrations of two different fuel-cell-dominant bus designs: Zero Emission Bay Area Demonstration Group led by Alameda-Contra Costa Transit District (AC Transit) in California; American Fuel Cell Bus (AFCB) Project at SunLine Transit Agency in California; AFCB Project at the University of California at Irvine; AFCB Project at Orange County Transportation Authority; and AFCB Project at Massachusetts Bay Transportation Authority.

  12. Safety issues in urban transit facilities for hydrogen-fueled buses

    International Nuclear Information System (INIS)

    Hay, R.H.; Ducharme, P.

    2004-01-01

    'Full text:' The Canadian Transportation Fuel Cell Alliance (CTFCA), created by the Canadian Government as part of its 2000 Climate Change Action Plan, has commissioned MARCON-DDM's Hydrogen Intervention Team (HIT) to provide a roadmap for urban transit systems that wish to move to hydrogen fuel cell-powered bus fleets. HIT is currently in the process of gathering information from hydrogen technology providers, bus manufacturers, fuelling system providers and urban transit systems in Canada, the US and Europe. In September, HIT will be in a position to provide a hands-on perspective of the introduction of fuel-cell buses in the Canadian environment. Part of the process of adding hydrogen-fueled busses to urban transit systems involves phasing in the new technology to minimize the economic cost. This involves substituting hydrogen buses into the normal bus procurement life cycle and maximizing the use of existing facilities for garaging, maintenance and fueling. Using a schematic outline of an urban transit system, this presentation will outline the safety issues specific to hydrogen in such systems, particularly for garaging, maintenance and fueling components. It will then outline how safety of these component is addressed in current and proposed codes, standards and recommended practices. Based on these requirements the impact of the introduction of hydrogen-fueled buses on each component of the transit system will be addressed in terms of the adaptations of current facilities and practices or the requirements for new facilities and practices. (author)

  13. Lifecycle cost assessment and carbon dioxide emissions of diesel, natural gas, hybrid electric, fuel cell hybrid and electric transit buses

    International Nuclear Information System (INIS)

    Lajunen, Antti; Lipman, Timothy

    2016-01-01

    This paper evaluates the lifecycle costs and carbon dioxide emissions of different types of city buses. The simulation models of the different powertrains were developed in the Autonomie vehicle simulation software. The carbon dioxide emissions were calculated both for the bus operation and for the fuel and energy pathways from well to tank. Two different operating environment case scenarios were used for the primary energy sources, which were Finland and California (USA). The fuel and energy pathways were selected appropriately in relation to the operating environment. The lifecycle costs take into account the purchase, operating, maintenance, and possible carbon emission costs. Based on the simulation results, the energy efficiency of city buses can be significantly improved by the alternative powertrain technologies. Hybrid buses have moderately lower carbon dioxide emissions during the service life than diesel buses whereas fully-electric buses have potential to significantly reduce carbon dioxide emissions, by up to 75%. The lifecycle cost analysis indicates that diesel hybrid buses are already competitive with diesel and natural gas buses. The high costs of fuel cell and battery systems are the major challenges for the fuel cell hybrid buses in order to reduce lifecycle costs to more competitive levels. - Highlights: • Alternative powertrains can significantly improve energy efficiency of transit buses. • Operating environment has an important impact on the lifecycle costs of buses. • Diesel hybrid buses are already cost effective solution for public transportation. • The cost of fuel cell technology is the major challenge for fuel cell hybrid buses. • Fully-electric buses have potential to significantly reduce carbon dioxide emissions.

  14. Environmental Technology Assessment of Introducing Fuel Cell City Buses. A Case Study of Fuel Cell Buses in Goeteborg

    Energy Technology Data Exchange (ETDEWEB)

    Karlstroem, Magnus

    2002-07-01

    Over the last several years, fuel cell systems have improved. These advancements have increased the expectations that fuel cells are a feasible option for several applications such as transportation and stationary use. There are several reasons why fuel cell buses in city centres appear to be the most beneficial market niche to begin introducing the technology in. The goal of the report is to compile information about fuel cell buses relevant for city administrators working with public transport and environmental issues. A literature review of the fuel cells in buses is included. This study also consists of an environmental assessment of using fuel cell buses with hydrogen produced in various ways for buses on bus route 60 in Goeteborg by 2006. The fuel cell buses are compared with other bus and fuel alternatives. There are two goals of the case study: 1. The first goal is to describe the technical system, the methodology, and the problem for the intended audience. In the future, this study could help frame future investment decisions. 2. The second goal is to present environmental performance results---emission, health, monetary---relative the alternative bus technologies. The model calculations showed that the social benefits were approximately SEK 910,000 each year if all buses were fuel cell buses compared with developed diesel buses. If the fuel cell buses were compared to natural gas buses, then the benefits were SEK 860,000 each year. The benefits were SEK 1.39/bus/km compared with diesel buses or SEK 1.30/bus/km compared with natural gas buses.

  15. National Fuel Cell Bus Program : Accelerated Testing Report, AC Transit

    Science.gov (United States)

    2009-01-01

    This is an evaluation of hydrogen fuel cell transit buses operating at AC Transit in revenue service since March 20, 2006 compared to similar diesel buses operating from the same depot. This evaluation report includes results from November 2007 throu...

  16. National Fuel Cell Bus Program: Accelerated Testing Evaluation Report and Appendices, Alameda-Contra Costa Transit District (AC Transit)

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2009-01-01

    This is an evaluation of hydrogen fuel cell transit buses operating at AC Transit in revenue service since March 20, 2006 compared to similar diesel buses operating from the same depot. This evaluation report includes results from November 2007 through October 2008. Evaluation results include implementation experience, fueling station operation, fuel cell bus operations at Golden Gate Transit, and evaluation results at AC Transit (bus usage, availability, fuel economy, maintenance costs, and roadcalls).

  17. In-vehicle measurement of ultrafine particles on compressed natural gas, conventional diesel, and oxidation-catalyst diesel heavy-duty transit buses.

    Science.gov (United States)

    Hammond, Davyda; Jones, Steven; Lalor, Melinda

    2007-02-01

    Many metropolitan transit authorities are considering upgrading transit bus fleets to decrease ambient criteria pollutant levels. Advancements in engine and fuel technology have lead to a generation of lower-emission buses in a variety of fuel types. Dynamometer tests show substantial reductions in particulate mass emissions for younger buses (vehicle particle number concentration measurements on conventional diesel, oxidation-catalyst diesel and compressed natural gas transit buses are compared to estimate relative in-vehicle particulate exposures. Two primary consistencies are observed from the data: the CNG buses have average particle count concentrations near the average concentrations for the oxidation-catalyst diesel buses, and the conventional diesel buses have average particle count concentrations approximately three to four times greater than the CNG buses. Particle number concentrations are also noticeably affected by bus idling behavior and ventilation options, such as, window position and air conditioning.

  18. BC Transit Fuel Cell Bus Project: Evaluation Results Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-02-01

    This report evaluates a fuel cell electric bus demonstration led by British Columbia Transit (BC Transit) in Whistler, Canada. BC Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's National Renewable Energy Laboratory to evaluate the buses in revenue service. This evaluation report covers two years of revenue service data on the buses from April 2011 through March 2013.

  19. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus Preliminary Evaluation Results

    Science.gov (United States)

    2008-10-16

    This report describes operations at Connecticut Transit (CTTRANSIT) in Hartford for one prototype fuel cell bus and three new diesel buses operating from the same location. The report discusses the planned fuel cell bus demonstration and equipment us...

  20. Real-time measurements of nitrogen oxide emissions from in-use New York City transit buses using a chase vehicle.

    Science.gov (United States)

    Shorter, Joanne H; Herndon, Scott; Zahniser, Mark S; Nelson, David D; Wormhoudt, Joda; Demerjian, Kenneth L; Kolb, Charles E

    2005-10-15

    New diesel engine technologies and alternative fuel engines are being introduced into fleets of mass transit buses to try to meet stricter emission regulations of nitrogen oxides and particulates: Real-time instruments including an Aerodyne Research tunable infrared laser differential absorption spectrometer (TILDAS) were deployed in a mobile laboratory to assess the impact of the implementation of the new technologies on nitrogen oxide emissions in real world driving conditions. Using a "chase" vehicle sampling strategy, the mobile laboratory followed target vehicles, repeatedly sampling their exhaust. Nitrogen oxides from approximately 170 in-use New York City mass transit buses were sampled during the field campaigns. Emissions from conventional diesel buses, diesel buses with continuously regenerating technology (CRT), diesel hybrid electric buses, and compressed natural gas (CNG) buses were compared. The chase vehicle sampling method yields real world emissions that can be included in more realistic emission inventories. The NO, emissions from the diesel and CNG buses were comparable. The hybrid electric buses had approximately one-half the NOx emissions. In CRT diesels, NO2 accounts for about one-third of the NOx emitted in the exhaust, while for non-CRT buses the NO2 fraction is less than 10%.

  1. Environmental, health, and safety issues of fuel cells in transportation. Volume 1: Phosphoric acid fuel-cell buses

    Energy Technology Data Exchange (ETDEWEB)

    Ring, S

    1994-12-01

    The U.S. Department of Energy (DOE) chartered the Phosphoric Acid Fuel-Cell (PAFC) Bus Program to demonstrate the feasibility of fuel cells in heavy-duty transportation systems. As part of this program, PAFC- powered buses are being built to meet transit industry design and performance standards. Test-bed bus-1 (TBB-1) was designed in 1993 and integrated in March 1994. TBB-2 and TBB-3 are under construction and should be integrated in early 1995. In 1987 Phase I of the program began with the development and testing of two conceptual system designs- liquid- and air-cooled systems. The liquid-cooled PAFC system was chosen to continue, through a competitive award, into Phase H, beginning in 1991. Three hybrid buses, which combine fuel-cell and battery technologies, were designed during Phase III. After completing Phase II, DOE plans a comprehensive performance testing program (Phase HI) to verify that the buses meet stringent transit industry requirements. The Phase III study will evaluate the PAFC bus and compare it to a conventional diesel bus. This NREL study assesses the environmental, health, and safety (EH&S) issues that may affect the commercialization of the PAFC bus. Because safety is a critical factor for consumer acceptance of new transportation-based technologies the study focuses on these issues. The study examines health and safety together because they are integrally related. In addition, this report briefly discusses two environmental issues that are of concern to the Environmental Protection Agency (EPA). The first issue involves a surge battery used by the PAFC bus that contains hazardous constituents. The second issue concerns the regulated air emissions produced during operation of the PAFC bus.

  2. An updated assessment of the prospects for fuel cell-powered buses. An information paper

    Energy Technology Data Exchange (ETDEWEB)

    Sanderson, T.K. [Future Energy Solutions, Harwell (United Kingdom)

    2005-07-01

    This report presents updated conclusions of the Department of Trade and Industry's research and development programme to assess the commercial prospects for advanced fuel cells in buses. The programme has focussed on low temperature solid polymer fuel cells (SPFCs) for transport and combined heat and power (CHP)/distributed power and high temperature solid oxide fuel cells (SOFCs) for CHP/distributed power. As well as assessing the prospects for SPFCs in buses, the report examines those for alkaline fuel cells (AFCs) and phosphoric acid fuel cells (PAFCs) in buses. The report provides an assessment of the status of technology development for different types of fuel cells in terms of applications to buses and offers estimates of market potential. Some fuel-cell powered buses are now available for demonstration purposes but the report concludes that truly commercial sales are unlikely to start before 2010 and widespread deployment is expected to take a further ten years after that. Buses have now slipped behind cars in terms of worldwide deployment. The issue of fuel choice is considered largely resolved with most fleet vehicle/bus manufacturers currently focussing on hydrogen as a fuel. A discussion of the prospects and barriers for fuel cell buses concludes that cost reduction is now the major barrier to the successful commercialisation of fuel cells in buses. More demonstration prototypes and field trials are required to provide information on energy, environmental and economic performance of fuel cell buses. Field trials could also provide information to assist the development of refuelling systems, fuel storage systems, stacks and other system components and to gain experience of building integrated fuel cell systems.

  3. Lagrangian Hotspots of In-Use NOX Emissions from Transit Buses.

    Science.gov (United States)

    Kotz, Andrew J; Kittelson, David B; Northrop, William F

    2016-06-07

    In-use, spatiotemporal NOX emissions were measured from a conventional powertrain transit bus and a series electric hybrid bus over gradients of route kinetic intensity and ambient temperature. This paper introduces a new method for identifying NOX emissions hotspots along a bus route using high fidelity Lagrangian vehicle data to explore spatial interactions that may influence emissions production. Our study shows that the studied transit buses emit higher than regulated emissions because on-route operation does not accurately represent the range of engine operation tested according to regulatory standards. Using the Lagrangian hotspot detection, we demonstrate that NOX hotspots occurred at bus stops, during cold starts, on inclines, and for accelerations. On the selected routes, bus stops resulted in 3.3 times the route averaged emissions factor in grams/km without significant dependence on bus type or climate. The buses also emitted 2.3 times the route averaged NOX emissions factor at the beginning of each route due to cold selective catalytic reduction aftertreatment temperature. The Lagrangian hotspot detection technique demonstrated here could be employed in future connected vehicles empowered by advances in computational power, data storage capability, and improved sensor technology to optimize emissions as a function of spatial location.

  4. BC Transit Fuel Cell Bus Project Evaluation Results: Second Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Post, M.

    2014-09-01

    Second report evaluating a fuel cell electric bus (FCEB) demonstration led by British Columbia Transit (BC Transit) in Whistler, Canada. BC Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's National Renewable Energy Laboratory to evaluate the buses in revenue service. NREL published its first report on the demonstration in February 2014. This report is an update to the previous report; it covers 3 full years of revenue service data on the buses from April 2011 through March 2014 and focuses on the final experiences and lessons learned.

  5. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2009-05-01

    This report describes operations at Connecticut Transit (CTTRANSIT) in Hartford for one prototype fuel cell bus and three new diesel buses operating from the same location. The evaluation period in this report (January 2008 through February 2009) has been chosen to coincide with a UTC Power propulsion system changeout that occurred on January 15, 2008.

  6. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third Evaluation Report and Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2010-01-01

    This report describes operations at Connecticut Transit (CTTRANSIT) in Hartford for one prototype fuel cell bus and three new diesel buses operating from the same location. The prototype fuel cell bus was manufactured by Van Hool and ISE Corp. and features an electric hybrid drive system with a UTC Power PureMotion 120 Fuel Cell Power System and ZEBRA batteries for energy storage. The fuel cell bus started operation in April 2007, and evaluation results through October 2009 are provided in this report.

  7. Comparative study of fuel cell, battery and hybrid buses for renewable energy constrained areas

    Science.gov (United States)

    Stempien, J. P.; Chan, S. H.

    2017-02-01

    Fuel cell- and battery-based public bus technologies are reviewed and compared for application in tropical urban areas. This paper scrutinizes the reported literature on fuel cell bus, fuel cell electric bus, battery electric bus, hybrid electric bus, internal combustion diesel bus and compressed natural gas bus. The comparison includes the capital and operating costs, fuel consumption and fuel cycle emissions. To the best of authors knowledge, this is the first study to holistically compare hydrogen and battery powered buses, which is the original contribution of this paper. Moreover, this is the first study to focus on supplying hydrogen and electricity from fossil resources, while including the associated emissions. The study shows that compressed natural gas and hybrid electric buses appear to be the cheapest options in terms of total cost of ownership, but they are unable to meet the EURO VI emissions' standard requirement. Only fuel cell based buses have the potential to achieve the emissions' standard when the fuel cycle based on fossil energy was considered. Fuel cell electric buses are identified as a technology allowing for the largest CO2 emission reduction, making ∼61% decrease in annual emissions possible.

  8. Microbial air quality in mass transport buses and work-related illness among bus drivers of Bangkok Mass Transit Authority.

    Science.gov (United States)

    Luksamijarulkul, Pipat; Sundhiyodhin, Viboonsri; Luksamijarulkul, Soavalug; Kaewboonchoo, Orawan

    2004-06-01

    The air quality in mass transport buses, especially air-conditioned buses may affect bus drivers who work full time. Bus numbers 16, 63, 67 and 166 of the Seventh Bus Zone of Bangkok Mass Transit Authority were randomly selected to investigate for microbial air quality. Nine air-conditioned buses and 2-4 open-air buses for each number of the bus (36 air-conditioned buses and 12 open-air buses) were included. Five points of in-bus air samples in each studied bus were collected by using the Millipore A ir Tester Totally, 180 and 60 air samples collected from air-conditioned buses and open-air buses were cultured for bacterial and fungal counts. The bus drivers who drove the studied buses were interviewed towards histories of work-related illness while working. The results revealed that the mean +/- SD of bacterial counts in the studied open-air buses ranged from 358.50 +/- 146.66 CFU/m3 to 506 +/- 137.62 CFU/m3; bus number 16 had the highest level. As well as the mean +/- SD of fungal counts which ranged from 93.33 +/- 44.83 CFU/m3 to 302 +/- 294.65 CFU/m3; bus number 166 had the highest level. Whereas, the mean +/- SD of bacterial counts in the studied air-conditioned buses ranged from 115.24 +/- 136.01 CFU/m3 to 244.69 +/- 234.85 CFU/m3; bus numbers 16 and 67 had the highest level. As well as the mean +/- SD of fungal counts which rangedfrom 18.84 +/- 39.42 CFU/m3 to 96.13 +/- 234.76 CFU/m3; bus number 166 had the highest level. When 180 and 60 studied air samples were analyzed in detail, it was found that 33.33% of the air samples from open-air buses and 6.11% of air samples from air-conditioned buses had a high level of bacterial counts (> 500 CFU/m3) while 6.67% of air samples from open-air buses and 2.78% of air samples from air-conditioned buses had a high level of fungal counts (> 500 CFU/m3). Data from the history of work-related illnesses among the studied bus drivers showed that 91.67% of open-air bus drivers and 57.28% of air-conditioned bus drivers had

  9. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2013

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gikakis, Christina [Federal Transit Administration, Washington, DC (United States)

    2013-12-01

    This report is the seventh in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. The report also provides a snapshot of current FCEB performance results from August 2012 through July 2013 for five FCEB demonstrations at four transit agencies.

  10. SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation Report (Report and Appendices)

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2009-01-01

    This report describes operations at SunLine Transit Agency for a prototype fuel cell bus and five new compressed natural gas (CNG) buses. This is the fourth evaluation report for this site, and it describes results and experiences from April 2008 through October 2008. These results are an addition to those provided in the previous three evaluation reports.

  11. SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation Report (Report and Appendices)

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.

    2009-08-01

    This report describes operations at SunLine Transit Agency for a prototype fuel cell bus and five compressed natural gas (CNG) buses. This is the fifth evaluation report for this site, and it describes results and experiences from October 2008 through June 2009. These results are an addition to those provided in the previous four evaluation reports.

  12. Fuel Cell Buses in U.S. Transit Fleets : Current Status 2014

    Science.gov (United States)

    2014-12-03

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. Various stakeholders, including d...

  13. Fuel Cell Buses in U.S. Transit Fleets : Current Status 2015

    Science.gov (United States)

    2015-12-01

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of ...

  14. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2017

    Science.gov (United States)

    2017-11-01

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of ...

  15. Fuel Cell Buses in U.S. Transit Fleets : Current Status 2013

    Science.gov (United States)

    2013-12-01

    This report is the seventh in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. This r...

  16. Fuel Cell Buses in U.S. Transit Fleets : Current Status 2012

    Science.gov (United States)

    2012-11-12

    This report is the sixth in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. The repo...

  17. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2011

    Science.gov (United States)

    2011-11-11

    his report is the fifth in a series of annual status reports that summarize the progress resulting from fuel cell transit bus demonstrations in the United States and provide a discussion of the achievements and challenges of fuel cell propulsion in t...

  18. NREL Evaluates Performance of Fast-Charge Electric Buses

    Energy Technology Data Exchange (ETDEWEB)

    2016-09-16

    This real-world performance evaluation is designed to enhance understanding of the overall usage and effectiveness of electric buses in transit operation and to provide unbiased technical information to other agencies interested in adding such vehicles to their fleets. Initial results indicate that the electric buses under study offer significant fuel and emissions savings. The final results will help Foothill Transit optimize the energy-saving potential of its transit fleet. NREL's performance evaluations help vehicle manufacturers fine-tune their designs and help fleet managers select fuel-efficient, low-emission vehicles that meet their bottom line and operational goals. help Foothill Transit optimize the energy-saving potential of its transit fleet. NREL's performance evaluations help vehicle manufacturers fine-tune their designs and help fleet managers select fuel-efficient, low-emission vehicles that meet their bottom line and operational goals.

  19. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Chandler, Kevin [Battelle, Columbus, OH (United States); Gikakis, Christina [Federal Transit Administration, Washington, DC (United States)

    2012-11-01

    This report is the sixth in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. The report also provides a snapshot of current FCEB performance results over the last year.

  20. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chander, K.; Gikakis, C.

    2012-11-01

    This report is the sixth in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. The report also provides a snapshot of current FCEB performance results over the last year. There are 25 active FCEBs in demonstrations this year at eight locations.

  1. Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration Results. Fourth Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-07-02

    This report presents results of a demonstration of fuel cell electric buses (FCEB) operating in Oakland, California. Alameda-Contra Costa Transit District (AC Transit) leads the Zero Emission Bay Area (ZEBA) demonstration, which includes 12 advanced-design fuel cell buses and two hydrogen fueling stations. The FCEBs in service at AC Transit are 40-foot, low-floor buses built by Van Hool with a hybrid electric propulsion system that includes a US Hybrid fuel cell power system and EnerDel lithium-based energy storage system. The buses began revenue service in May 2010.

  2. Towards sustainable urban transportation: Test, demonstration and development of fuel cell and hybrid-electric buses

    International Nuclear Information System (INIS)

    Folkesson, Anders

    2008-05-01

    Several aspects make today's transport system non-sustainable: - Production, transport and combustion of fossil fuels lead to global and local environmental problems. - Oil dependency in the transport sector may lead to economical and political instability. - Air pollution, noise, congestion and land-use may jeopardise public health and quality of life, especially in urban areas. In a sustainable urban transport system most trips are made with public transport because high convenience and comfort makes travelling with public transport attractive. In terms of emissions, including noise, the vehicles are environmentally sustainable, locally as well as globally. Vehicles are energy-efficient and the primary energy stems from renewable sources. Costs are reasonable for all involved, from passengers, bus operators and transport authorities to vehicle manufacturers. The system is thus commercially viable on its own merits. This thesis presents the results from three projects involving different concept buses, all with different powertrains. The first two projects included technical evaluations, including tests, of two different fuel cell buses. The third project focussed on development of a series hybrid-bus with internal combustion engine intended for production around 2010. The research on the fuel cell buses included evaluations of the energy efficiency improvement potential using energy mapping and vehicle simulations. Attitudes to hydrogen fuel cell buses among passengers, bus drivers and bus operators were investigated. Safety aspects of hydrogen as a vehicle fuel were analysed and the use of hydrogen compared to electrical energy storage were also investigated. One main conclusion is that a city bus should be considered as one energy system, because auxiliaries contribute largely to the energy use. Focussing only on the powertrain is not sufficient. The importance of mitigating losses far down an energy conversion chain is emphasised. The Scania hybrid fuel cell

  3. Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration Results: Fifth Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jeffers, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-06-01

    This report presents results of a demonstration of fuel cell electric buses (FCEB) operating in Oakland, California. Alameda-Contra Costa Transit District (AC Transit) leads the Zero Emission Bay Area (ZEBA) demonstration, which includes 13 advanced-design fuel cell buses and two hydrogen fueling stations. The ZEBA partners are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service. NREL has published four previous reports describing operation of these buses. This report presents new and updated results covering data from January 2015 through December 2015.

  4. Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration Results: Sixth Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Post, Matthew B. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jeffers, Matthew A. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-11

    This report presents results of a demonstration of fuel cell electric buses (FCEB) operating in Oakland, California. Alameda-Contra Costa Transit District (AC Transit) leads the Zero Emission Bay Area (ZEBA) demonstration, which includes 13 advanced-design fuel cell buses and two hydrogen fueling stations. The ZEBA partners are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service. NREL has published five previous reports describing operation of these buses. This report presents new and updated results covering data from January 2016 through December 2016.

  5. Simulations of the Fuel Economy and Emissions of Hybrid Transit Buses over Planned Local Routes

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Zhiming [ORNL; LaClair, Tim J [ORNL; Daw, C Stuart [ORNL; Smith, David E [ORNL; Franzese, Oscar [ORNL

    2014-01-01

    We present simulated fuel economy and emissions city transit buses powered by conventional diesel engines and diesel-hybrid electric powertrains of varying size. Six representative city drive cycles were included in the study. In addition, we included previously published aftertreatment device models for control of CO, HC, NOx, and particulate matter (PM) emissions. Our results reveal that bus hybridization can significantly enhance fuel economy by reducing engine idling time, reducing demands for accessory loads, exploiting regenerative braking, and shifting engine operation to speeds and loads with higher fuel efficiency. Increased hybridization also tends to monotonically reduce engine-out emissions, but trends in the tailpipe (post-aftertreatment) emissions involve more complex interactions that significantly depend on motor size and drive cycle details.

  6. Life Cycle Assessment of Diesel and Electric Public Transportation Buses

    Science.gov (United States)

    The Clean Air Act identifies diesel powered motor vehicles, including transit buses, as significant sources of several criteria pollutants which contribute to ground level ozone formation or smog. The effects of air pollution in urban areas are often more significant due to con...

  7. American Fuel Cell Bus Project Evaluation. Second Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-09-01

    This report presents results of the American Fuel Cell Bus (AFCB) Project, a demonstration of fuel cell electric buses operating in the Coachella Valley area of California. The prototype AFCB was developed as part of the Federal Transit Administration's (FTA's) National Fuel Cell Bus Program. Through the non-profit consortia CALSTART, a team led by SunLine Transit Agency and BAE Systems developed a new fuel cell electric bus for demonstration. SunLine added two more AFCBs to its fleet in 2014 and another in 2015. FTA and the AFCB project team are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory to evaluate the buses in revenue service. This report summarizes the performance results for the buses through June 2015.

  8. Development of CH{sub 3}OH fueled PEMFC power plants for hybrid transit buses

    Energy Technology Data Exchange (ETDEWEB)

    Baumert, R; Cooper, R; Feasey, G [DBB Fuel Cell Engines Corp., Poway, CA (United States)

    1999-12-31

    An overview of the methanol fuel cell power system was provided, identifying improved efficiency and reduced emissions as the principal advantages. Four critical tasks regarding on-board fuel processing were described: (1) efficient methanol conversion (steam reforming), (2) effective reformate purification (selective catalytic oxidation), (3) optimized heat integration, and (4) rapid response to transients. A description of a 100 kW PEM fuel cell bus engine package was also presented. As far as a development time table is concerned, the DBB Fuel Cell Engines Corp. of Poway California has completed two methanol fueled PEMFC power plants, fabrication of the initial 100 kW PEMFC engine is in progress and scheduled for delivery by 1998. The two methanol fueled commercial products which are in the planning stages are the 100 and 200 kW class FCPS for hybrid and non-hybrid buses and other applications. tabs., figs.

  9. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: First Results Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.

    2011-03-01

    This report describes operations at SunLine Transit Agency for their newest prototype fuel cell bus and five compressed natural gas (CNG) buses. In May 2010, SunLine began operating its sixth-generation hydrogen fueled bus, an Advanced Technology (AT) fuel cell bus that incorporates the latest design improvements to reduce weight and increase reliability and performance. The agency is collaborating with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to evaluate the bus in revenue service. This report provides the early data results and implementation experience of the AT fuel cell bus since it was placed in service.

  10. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Fourth Results Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.

    2013-01-01

    SunLine Transit Agency, which provides public transit services to the Coachella Valley area of California, has demonstrated hydrogen and fuel cell bus technologies for more than 10 years. In May 2010, SunLine began demonstrating the advanced technology (AT) fuel cell bus with a hybrid electric propulsion system, fuel cell power system, and lithium-based hybrid batteries. This report describes operations at SunLine for the AT fuel cell bus and five compressed natural gas buses. The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is working with SunLine to evaluate the bus in real-world service to document the results and help determine the progress toward technology readiness. NREL has previously published three reports documenting the operation of the fuel cell bus in service. This report provides a summary of the results with a focus on the bus operation from February 2012 through November 2012.

  11. In-use fuel economy of hybrid-electric school buses in Iowa.

    Science.gov (United States)

    Hallmark, Shauna; Sperry, Bob; Mudgal, Abhisek

    2011-05-01

    Although it is much safer and more fuel-efficient to transport children to school in buses than in private vehicles, school buses in the United States still consume 822 million gal of diesel fuel annually, and school transportation costs can account for a significant portion of resource-constrained school district budgets. Additionally, children in diesel-powered school buses may be exposed to higher levels of particulates and other pollutants than children in cars. One solution to emission and fuel concerns is use of hybrid-electric school buses, which have the potential to reduce emissions and overall lifecycle costs compared with conventional diesel buses. Hybrid-electric technologies are available in the passenger vehicle market as well as the transit bus market and have a track record indicating fuel economy and emissions benefits. This paper summarizes the results of an in-use fuel economy evaluation for two plug-in hybrid school buses deployed in two different school districts in Iowa. Each school district selected a control bus with a route similar to that of the hybrid bus. Odometer readings, fuel consumption, and maintenance needs were recorded for each bus. The buses were deployed in 2008 and data were collected through May 2010. Fuel consumption was calculated for each school district. In Nevada, IA, the overall average fuel economy was 8.23 mpg for the hybrid and 6.35 mpg for the control bus. In Sigourney, IA, the overall average fuel economy was 8.94 mpg for the hybrid and 6.42 mpg for the control bus. The fuel consumption data were compared for the hybrid and control buses using a Wilcoxon signed rank test. Results indicate that fuel economy for the Nevada hybrid bus was 29.6% better than for the Nevada control bus, and fuel economy for the Sigourney hybrid bus was 39.2% higher than for the Sigourney control bus. Both differences were statistically significant.

  12. Buse_Francisella and free-living amoebae data sets

    Data.gov (United States)

    U.S. Environmental Protection Agency — Co-infection data in the form of colony forming units and amoeba cell counts. This dataset is associated with the following publication: Buse , H., F. Schaefer, and...

  13. Electric buses - An energy efficient urban transportation means

    Energy Technology Data Exchange (ETDEWEB)

    Kuehne, Reinhart [German Aerospace Center (DLR), Transportation Studies, Rutherfordstr. 2, 12489 Berlin (Germany)

    2010-12-15

    Bus transit systems with electric traction are an important contribution to the post fossil fuel mobility. Most renewable energy sources provide energy in the form of electricity. Electric motors thus have promise in the development of the way ''beyond oil''. The reactivation of trolley bus systems - grid bounded but also catenary free for short distances - paves this way. The design of modern trolley bus operations overcomes the existing disadvantages of conventional buses using fossil fuel. Germany has an efficient industry in this field, that offers braking energy recovery and energy storage in modern supercapacitors as well as technical and organisational innovations for a local emission free and a low noise transit system. Gentle but powerful when starting and braking, the trolley bus is cost effective and easy to integrate into an existing infrastructure. Such an electric bus system is ecological, customer-friendly and suitable for cities. It has a high economic efficiency and it also expands the traffic planning field towards an ecological future technology. This paper shows examples at home and abroad how electric buses achieve an energy solving modern urban traffic. It gives insights into technical developments of electric vehicle equipment, cateneries with fast driving handling characteristics and the use of plain electric and hybrid powertrains. (author)

  14. Unregulated emissions from compressed natural gas (CNG) transit buses configured with and without oxidation catalyst.

    Science.gov (United States)

    Okamoto, Robert A; Kado, Norman Y; Kuzmicky, Paul A; Ayala, Alberto; Kobayashi, Reiko

    2006-01-01

    The unregulated emissions from two in-use heavy-duty transit buses fueled by compressed natural gas (CNG) and equipped with oxidation catalyst (OxiCat) control were evaluated. We tested emissions from a transit bus powered by a 2001 Cummins Westport C Gas Plus 8.3-L engine (CWest), which meets the California Air Resources Board's (CARB) 2002 optional NOx standard (2.0 g/bhp-hr). In California, this engine is certified only with an OxiCat, so our study did not include emissions testing without it. We also tested a 2000 New Flyer 40-passenger low-floor bus powered by a Detroit Diesel series 50G engine (DDCs50G) that is currently certified in California without an OxiCat. The original equipment manufacturer (OEM) offers a "low-emission" package for this bus that includes an OxiCat for transit bus applications, thus, this configuration was also tested in this study. Previously, we reported that formaldehyde and other volatile organic emissions detected in the exhaust of the DDCs50G bus equipped with an OxiCat were significantly reduced relative to the same DDCs50G bus without OxiCat. In this paper, we examine othertoxic unregulated emissions of significance. The specific mutagenic activity of emission sample extracts was examined using the microsuspension assay. The total mutagenic activity of emissions (activity per mile) from the OxiCat-equipped DDC bus was generally lower than that from the DDC bus without the OxiCat. The CWest bus emission samples had mutagenic activity that was comparable to that of the OxiCat-equipped DDC bus. In general, polycyclic aromatic hydrocarbon (PAH) emissions were lower forthe OxiCat-equipped buses, with greater reductions observed for the volatile and semivolatile PAH emissions. Elemental carbon (EC) was detected in the exhaust from the all three bus configurations, and we found that the total carbon (TC) composition of particulate matter (PM) emissions was primarily organic carbon (OC). The amount of carbon emissions far exceeded the

  15. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Third Results Reports

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.

    2012-05-01

    This report describes operations at SunLine Transit Agency for their newest prototype fuel cell bus and five compressed natural gas (CNG) buses. In May 2010, SunLine began operating its sixth-generation hydrogen fueled bus, an Advanced Technology (AT) fuel cell bus that incorporates the latest design improvements to reduce weight and increase reliability and performance. The agency is collaborating with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to evaluate the bus in revenue service. NREL has previously published two reports documenting the operation of the fuel cell bus in service. This report provides a summary of the results with a focus on the bus operation from July 2011 through January 2012.

  16. Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration: First Results Report

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2011-08-01

    This report documents the early implementation experience for the Zero Emission Bay Area (ZEBA) Demonstration, the largest fleet of fuel cell buses in the United States. The ZEBA Demonstration group includes five participating transit agencies: AC Transit (lead transit agency), Santa Clara Valley Transportation Authority (VTA), Golden Gate Transit (GGT), San Mateo County Transit District (SamTrans), and San Francisco Municipal Railway (Muni). The ZEBA partners are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service.

  17. Evaluating real-world CO2 and NOX emissions for public transit buses using a remote wireless on-board diagnostic (OBD) approach.

    Science.gov (United States)

    Yang, Liuhanzi; Zhang, Shaojun; Wu, Ye; Chen, Qizheng; Niu, Tianlin; Huang, Xu; Zhang, Shida; Zhang, Liangjun; Zhou, Yu; Hao, Jiming

    2016-11-01

    The challenge to mitigate real-world emissions from vehicles calls for powerful in-use compliance supervision. The remote on-board diagnostic (OBD) approach, with wireless data communications, is one of the promising next-generation monitoring methods. We collected second-by-second profiles of carbon dioxide (CO 2 ) and nitrogen oxides (NO X ) emissions, driving conditions and engine performance for three conventional diesel and three hybrid diesel buses participating in a remote OBD pilot program in Nanjing, China. Our results showed that the average CO 2 emissions for conventional diesel and hybrid diesel buses were 816 ± 83 g km -1 and 627 ± 54 g km -1 , respectively, under a typical driving pattern. An operating mode binning analysis indicated that CO 2 emissions reduction by series-parallel hybrid technology was largely because of the significant benefits of the technology under the modes of low speed and low power demand. However, significantly higher CO 2 emissions were observed for conventional diesel buses during rush hours, higher than 1200 g km -1 . The OBD data suggested no improvement in NO X emission reduction for hybrid buses compared with conventional buses; both were approximately 12 g km -1 because of poor performance of the selective catalyst reduction (SCR) systems in the real world. Speed-dependent functions for real-world CO 2 and NO X emissions were also constructed. The CO 2 emissions of hybrid buses were much less sensitive to the average speed than conventional buses. If the average speed decreased from 20 km h -1 to 10 km h -1 , the estimated CO 2 emission factor for conventional buses would be increased by 34%. Such a change in speed would increase NO X emissions for conventional and hybrid buses by 38% and 56%, respectively. This paper demonstrates the useful features of the remote OBD system and can inform policy makers how to take advantage of these features in monitoring in-use vehicles. Copyright © 2016 Elsevier

  18. Cost Effectiveness Analysis of Quasi-In-Motion Wireless Power Transfer for Plug-In Hybrid Electric Transit Buses from Fleet Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lijuan; Gonder, Jeff; Brooker, Aaron; Meintz, Andrew; Konan, Arnaud; Markel, Tony

    2016-05-16

    This study evaluated the costs and benefits associated with the use of stationary-wireless-power-transfer-enabled plug-in hybrid electric buses and determined the cost effectiveness relative to conventional buses and hybrid electric buses. A factorial design was performed over a number of different battery sizes, charging power levels, and f bus stop charging stations. The net present costs were calculated for each vehicle design and provided the basis for design evaluation. In all cases, given the assumed economic conditions, the conventional bus achieved the lowest net present cost while the optimal plug-in hybrid electric bus scenario beat out the hybrid electric comparison scenario. The parameter sensitivity was also investigated under favorable and unfavorable market penetration assumptions.

  19. Buses involved in fatal accidents factbook 2007

    Science.gov (United States)

    2010-03-01

    This document presents aggregate statistics on buses involved in traffic accidents in 2007. The : statistics are derived from the Buses Involved in Fatal Accidents (BIFA) file, compiled by the : University of Michigan Transportation Research Institut...

  20. Gas Phase Emission Ratios From In-Use Diesel and CNG Curbside Passenger Buses in New York City

    Science.gov (United States)

    Herndon, S. C.; Shorter, J.; Canagaratna, M.; Jayne, J.; Nelson, D. D.; Wormhoudt, J. C.; Williams, P.; Silva, P. J.; Shi, Q.; Ghertner, A.; Zahniser, M.; Worsnop, D.; Kolb, C.; Lanni, T.; Drewnick, F.; Demerjian, K. L.

    2002-12-01

    The Aerodyne Mobile Laboratory simultaneously measured gas phase and particulate emissions from in use vehicles during two campaigns in New York City. The campaigns took place during two weeks in October, 2000 and four weeks in July-August, 2001. Passenger curbside buses were the primary focus of the study, but school buses and several other heavy duty diesel vehicles were also characterized. This paper describes the methodologies used to measure individual in use vehicles and presents the results of the gas phase measurements. Emission ratios for NO, NO2, SO2, N2O, CO, CH4 and H2CO relative to CO2 have been determined across several classes of buses. The gas phase concentrations were measured each second, using Tunable Infrared Laser Direct Absorption Spectroscopy (TILDAS). Some of the categories of buses into which the data has been sorted are; diesel (both 6V92 and Series 50) with and without the Continuous Regenerative Technology (CRT) retrofit, compressed natural gas powered(CNG) and hybrid diesel-electric buses. The New York Metropolitan Transit Authority (MTA) cooperated with this work, providing details about each of their buses followed. In addition to MTA buses, other New York City passenger bus operators were also measured. In September 2000, MTA began to switch to 30 ppm sulfur diesel fuel while it is believed the non MTA operators did not. The measured emission ratios show that low sulfur fuel greatly reduces the amount of SO2 per CO2. Roughly one third of the MTA fleet of diesel buses have been equipped with the CRT retrofit. The gas phase results of interest in this category show increased direct emission of NO2 and companion work (also submitted to the 12th CRC) show the impact the CRT refit has on particulate emissions. CNG buses show increased H2CO and CH4 emission ratios relative to diesel powered motors.

  1. Buse_Francisella Medium

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset contains colony forming unit and qPCR data. This dataset is associated with the following publication: Morris, B., H. Buse, N. Adcock, and E. Rice. A...

  2. Buses involved in fatal accidents codebook 2008.

    Science.gov (United States)

    2011-03-01

    This report provides documentation for UMTRIs file of Buses Involved in Fatal Accidents (BIFA), 2008, : including distributions of the code values for each variable in the file. The 2008 BIFA file is a census of all : buses involved in a fatal acc...

  3. Buses involved in fatal accidents codebook 2007.

    Science.gov (United States)

    2009-12-01

    This report provides documentation for UMTRIs file of Buses Involved in Fatal Accidents (BIFA), 2007, : including distributions of the code values for each variable in the file. The 2007 BIFA file is a census of all : buses involved in a fatal acc...

  4. Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration Results: Sixth Report

    Science.gov (United States)

    2017-09-01

    This report presents results of a demonstration of fuel cell electric buses (FCEBs) operating in Oakland, California. Alameda-Contra Costa Transit District (AC Transit) leads the Zero Emission Bay Area (ZEBA) demonstration that includes 13 advanced-d...

  5. 49 CFR 393.89 - Buses, driveshaft protection.

    Science.gov (United States)

    2010-10-01

    ... ACCESSORIES NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.89 Buses, driveshaft protection. Any driveshaft extending lengthways under the floor of the passenger compartment of a bus shall... 49 Transportation 5 2010-10-01 2010-10-01 false Buses, driveshaft protection. 393.89 Section 393...

  6. Thermal Safety of the Current Buses in the Chimney of the D0 Solenoid

    International Nuclear Information System (INIS)

    Smith, R.P.

    1998-01-01

    The thermal and electrical behaviour of the current buses in the chimney of the D0 solenoid during upset conditions is modeled to guide the selection of trip levels for magnet protection circuits which discharge the magnet if abnormal conditions are detected. The current buses in the chimney are designed to operate safely without likelihood of loss of superconductivity as long as normal cooling conditions are maintained. Helium liquid level probes, helium flow instrumentation, and thermometry all are provided to certify that proper cooling conditions exist in the subcooler and chimney at all times. Rising temperatures in any portion of the system, excessive voltage drops on the vapor cooled leads, or decreasing liquid level in the subcooler or flow rate in the system, will each cause the fast discharge system to be triggered. Postulated failures of the helium flow system, somehow undetected by any and all of the aforementioned instrumentation, can in principal eventually lead to loss of superconductivity in the buses. Quenching in one bus will rapidly lead to quenching in the other. Potential taps on the buses and magnet coil halves connected to voltage-detection bridges external to the system provide at least dually redundant signals which will unambiguously trigger the magnet rapid discharge system. The conservative design of the bus system ensures that it will not be damaged during such incidents, however improbable they may be. The transition leads in the subcooler are equally conservatively designed, and would not be damaged if they were operated in a fully non-superconducting state for several minutes. The loss of liquid helium in the sub cooler required to cause this condition would imply that helium flow from the magnet had stopped, which in turn would imply that flow to the magnet had also stopped. The lack of flow into the sub cooler would result in insufficient flow to the vapor cooled leads. Any or all of these conditions would be detected, as would

  7. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Second Results Report and Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.

    2011-10-01

    This report describes operations at SunLine Transit Agency for their newest prototype fuel cell bus and five compressed natural gas (CNG) buses. In May 2010, SunLine began operating its sixth-generation hydrogen fueled bus, an Advanced Technology (AT) fuel cell bus that incorporates the latest design improvements to reduce weight and increase reliability and performance. The agency is collaborating with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to evaluate the bus in revenue service. This is the second results report for the AT fuel cell bus since it was placed in service, and it focuses on the newest data analysis and lessons learned since the previous report. The appendices, referenced in the main report, provide the full background for the evaluation. They will be updated as new information is collected but will contain the original background material from the first report.

  8. Air quality in inter-city buses : final report

    International Nuclear Information System (INIS)

    2005-01-01

    Various studies have suggested that air quality inside automobiles and school buses may be poorer than ambient or nearby air quality, and that concentrations of vehicle-related pollutants in city buses may be sufficiently elevated to pose concerns for vehicle occupants and operators. This paper presented the results of preliminary investigation of levels of some pollutants in inter-city buses to determine whether a fuller investigation is warranted. Another objective of the investigation was to develop methods for assessing air quality within road vehicles. Students carried monitoring equipment on 28 inter-city trips made by Greyhound Canada buses during July and August 2004. The equipment recorded average levels of carbon monoxide (CO) and nitrogen dioxide (NO 2 ), as well as concentrations of particulate matter. Bus routes were selected that allowed for an average of 10 hours of total sampling time in a day. Data was recorded on pumps, run times and routes taken. Results indicated that levels of CO in the buses were much lower than the national standard of acceptable levels for CO. Levels of NO 2 were on average lower, but 5 of the 19 recorded values exceeded acceptable levels. Average particulate levels recorded in the buses were considered acceptable, although some of the recorded levels were higher than desirable. It was concluded that further work on in-vehicle levels of NO 2 and particulate matter could be warranted. Although several procedural and equipment problems were encountered, the methods used in the investigation appeared to be valid, and were thought to be suitable for further work on in-vehicle concentrations of pollutants. 21 refs

  9. Alternative Fuels Data Center: Pennsylvania School Buses Run on Natural Gas

    Science.gov (United States)

    Pennsylvania School Buses Run on Natural Gas to someone by E-mail Share Alternative Fuels Data Center: Pennsylvania School Buses Run on Natural Gas on Facebook Tweet about Alternative Fuels Data Center: Pennsylvania School Buses Run on Natural Gas on Twitter Bookmark Alternative Fuels Data Center

  10. 46 CFR 111.30-19 - Buses and wiring.

    Science.gov (United States)

    2010-10-01

    ... control wiring must be— (1) Suitable for installation within in a switchboard enclosure and be rated at 90... 46 Shipping 4 2010-10-01 2010-10-01 false Buses and wiring. 111.30-19 Section 111.30-19 Shipping... REQUIREMENTS Switchboards § 111.30-19 Buses and wiring. (a) General. Each bus must meet the requirements of...

  11. Big Brother Is Watching: Video Surveillance on Buses

    Science.gov (United States)

    Sloggett, Joel

    2009-01-01

    Many school districts in North America have adopted policies to permit cameras on their properties and, when needed, on buses used to transport students. With regard to school buses, the camera is typically a tool for gathering information to monitor behavior or to help investigate a complaint about behavior. If a picture is worth a thousand…

  12. Is the public willing to pay for hydrogen buses? A comparative study of preferences in four cities

    International Nuclear Information System (INIS)

    O'Garra, Tanya; Mourato, Susana; Garrity, Lisa; Schmidt, Patrick; Beerenwinkel, Anne; Altmann, Matthias; Hart, David; Graesel, Cornelia; Whitehouse, Simon

    2007-01-01

    This paper presents results from the international AcceptH2 study (http://www.accepth2.com) of acceptability and preferences for hydrogen fuel cell (FC) buses. Using the contingent valuation method, this paper compares public willingness to pay (WTP) for the air pollution reductions associated with a scenario of large-scale introduction of hydrogen (H 2 ) FC buses in four cities: Berlin, London, Luxembourg and Perth. Results indicate that bus users in all cities have a positive WTP for H 2 buses, and that values (adjusted to the cost of living in each city) are very similar across geographical locations (ranging from WTP an extra Euro 0.29 to Euro 0.35 per single bus fare). Non-bus users were also interviewed in London and Perth, in order to capture values for the whole populations in these cities. Combined results for bus users and non-bus users confirm that overall residents in these cities are willing to pay extra (in taxes) to support the large-scale introduction of H 2 -buses

  13. 49 CFR 393.90 - Buses, standee line or bar.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Buses, standee line or bar. 393.90 Section 393.90 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.90 Buses, standee line or bar. Except...

  14. Particle and gaseous emissions from individual diesel and CNG buses

    Directory of Open Access Journals (Sweden)

    Å. M. Hallquist

    2013-05-01

    Full Text Available In this study size-resolved particle and gaseous emissions from 28 individual diesel-fuelled and 7 compressed natural gas (CNG-fuelled buses, selected from an in-use bus fleet, were characterised for real-world dilution scenarios. The method used was based on using CO2 as a tracer of exhaust gas dilution. The particles were sampled by using an extractive sampling method and analysed with high time resolution instrumentation EEPS (10 Hz and CO2 with a non-dispersive infrared gas analyser (LI-840, LI-COR Inc. 1 Hz. The gaseous constituents (CO, HC and NO were measured by using a remote sensing device (AccuScan RSD 3000, Environmental System Products Inc.. Nitrogen oxides, NOx, were estimated from NO by using default NO2/NOx ratios from the road vehicle emission model HBEFA3.1. The buses studied were diesel-fuelled Euro III–V and CNG-fuelled Enhanced Environmentally Friendly Vehicles (EEVs with different after-treatment, including selective catalytic reduction (SCR, exhaust gas recirculation (EGR and with and without diesel particulate filter (DPF. The primary driving mode applied in this study was accelerating mode. However, regarding the particle emissions also a constant speed mode was analysed. The investigated CNG buses emitted on average a higher number of particles but less mass compared to the diesel-fuelled buses. Emission factors for number of particles (EFPN were EFPN, DPF = 4.4 ± 3.5 × 1014, EFPN, no DPF = 2.1 ± 1.0 × 1015 and EFPN, CNG = 7.8 ± 5.7 ×1015 kg fuel−1. In the accelerating mode, size-resolved emission factors (EFs showed unimodal number size distributions with peak diameters of 70–90 nm and 10 nm for diesel and CNG buses, respectively. For the constant speed mode, bimodal average number size distributions were obtained for the diesel buses with peak modes of ~10 nm and ~60 nm. Emission factors for NOx expressed as NO2 equivalents for the diesel buses were on average 27 ± 7 g (kg fuel−1 and for the CNG buses 41

  15. 49 CFR 392.63 - Towing or pushing loaded buses.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Towing or pushing loaded buses. 392.63 Section 392... COMMERCIAL MOTOR VEHICLES Prohibited Practices § 392.63 Towing or pushing loaded buses. No disabled bus with... passengers aboard for the purpose of towing or pushing any disabled motor vehicle, except in such...

  16. Crashworthiness evaluation of mass transit buses.

    Science.gov (United States)

    2008-11-01

    Mass transit bus systems are an integral part of the national transportation network, serving more than 20.6 billion passenger-miles per year with a relatively low fatality rate. Bus occupant injuries are evenly distributed among crashes on all sides...

  17. 76 FR 53102 - Federal Motor Vehicle Safety Standards; Denial of Petition for Rulemaking; School Buses

    Science.gov (United States)

    2011-08-25

    ... small school buses to provide adequate crash protection for the occupants. For large school buses, FMVSS... and crash protection,'' requires lap/shoulder belts for all seating positions on small school buses... for adequate occupant crash protection. For large school buses, we have determined there is not a...

  18. Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration Results: Third Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Post, M.

    2014-05-01

    This report presents results of a demonstration of 12 fuel cell electric buses (FCEB) operating in Oakland, California. The 12 FCEBs operate as a part of the Zero Emission Bay Area (ZEBA) Demonstration, which also includes two new hydrogen fueling stations. This effort is the largest FCEB demonstration in the United States and involves five participating transit agencies. The ZEBA partners are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service. NREL has published two previous reports, in August 2011 and July 2012, describing operation of these buses. New results in this report provide an update covering eight months through October 2013.

  19. Transit's leading edge : innovations in service and technology : issue paper 7

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-11-01

    The Canadian Urban Transit Association is committed to raising awareness of the social, environmental and economic benefits of mass transit systems. Innovation is needed to address the challenges of attracting new riders, resolving fiscal imbalances, and meeting environmental concerns. This issue paper presents examples of how Canada's transit industry has used innovation to address the issue of climate change and fight smog. It includes a brief description of some of the ways that Canadian transit suppliers and transit systems are going green: Canada's bus builders are developing hybrid buses; Grand River Transit is improving air quality with clean diesel; Montreal's Transit Society is reducing emissions with biodiesel buses; Saskatoon Transit Service is using biodiesel buses; Laval's Transit Society is listening to customer complaints in an effort to reduce response times and improve customer service; Canadian Urban Transit Association is improving customer service; Transit Windsor is promoting a smog solution; Winnipeg Transit is working with employers to boost ridership; Trapeze Software Group is providing customers with quick and accurate trip itineraries; St. John's Transportation Commission has added solar-powered, light emitting diode illumination to bus stops; the City of Ottawa has an established transit priority measures; and, Infodev EDI Inc. has supplied automated high-technology solutions for passenger counting and vehicle location tracking to several Canadian transit systems. refs., figs.

  20. COORDINATION OF THE WORK OF BUSES IN CITY ROUTES

    Directory of Open Access Journals (Sweden)

    Fuad DASHDAMIROV

    2013-12-01

    Full Text Available The paper studied the work of bus routes passing through a street. Optimality criterion was chosen for the development of appropriate models of effective work of buses on the land. The paper proposes a new model costing time passengers at bus stops. A method of technique was developed to coordinate the buses running on the combined section of route.

  1. Natural gas drive for city buses in Skopje

    International Nuclear Information System (INIS)

    Dimitrovski, Mile; Veljanovski, Krsto; Dimitrovski, Dame

    2002-01-01

    Emission improvement in both city centers and conurbations is an important factor which developers of public-utility vehicles and buses must take into account. If natural gas is used as a fuel the emission is considerably lower than that from conventional diesel drive. Thus it is an important contribution to keep the air clean in the area where the vehicles are deployed. In this paper the project 'Ecological Natural gas drive for city buses in Skopje' is analysed. (Original)

  2. American Fuel Cell Bus Project Evaluation: Third Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jeffers, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-05-01

    This report presents results of the American Fuel Cell Bus (AFCB) Project, a demonstration of fuel cell electric buses operating in the Coachella Valley area of California. The prototype AFCB, which was developed as part of the Federal Transit Administration's (FTA) National Fuel Cell Bus Program, was delivered to SunLine in November 2011 and was put in revenue service in mid-December 2011. Two new AFCBs with an upgraded design were delivered in June/July of 2014 and a third new AFCB was delivered in February 2015. FTA and the AFCB project team are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory to evaluate the buses in revenue service. This report covers the performance of the AFCBs from July 2015 through December 2016.

  3. Alternative fuel buses currently in use in China: Life-cycle fossil energy use, GHG emissions and policy recommendations

    International Nuclear Information System (INIS)

    Ou Xunmin; Zhang Xiliang; Chang Shiyan

    2010-01-01

    The Chinese government has enacted policies to promote alternative vehicle fuels (AVFs) and alternative fuel vehicles (AFVs), including city bus fleets. The life cycle (LC), energy savings (ES) and GHG reduction (GR) profiles of AVFs/AFVs are critical to those policy decisions. The well-to-wheels module of the Tsinghua-CA3EM model is employed to investigate actual performance data. Compared with conventional buses, AFVs offer differences in performance in terms of both ES and GR. Only half of the AFVs analyzed demonstrate dual benefits. However, all non-oil/gas pathways can substitute oil/gas with coal. Current policies seek to promote technology improvements and market creation initiatives within the guiding framework of national-level diversification and district-level uniformity. Combined with their actual LC behavior and in keeping with near- and long-term strategies, integrated policies should seek to (1) apply hybrid electric technology to diesel buses; (2) encourage NG/LPG buses in gas-abundant cities; (3) promote commercialize electric buses or plug-in capable vehicles through battery technology innovation; (4) support fuel cell buses and hydrogen technology R and D for future potential applications; and (5) conduct further research on boosting vehicle fuel efficiency, applying low-carbon transportation technologies, and addressing all resultant implications of coal-based transportation solutions to human health and natural resources.

  4. Alternative fuel buses currently in use in China: Life-cycle fossil energy use, GHG emissions and policy recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Ou Xunmin, E-mail: oxm07@mails.tsinghua.edu.c [School of Public Policy and Management (SPPM), Tsinghua University, Beijing 100084 (China); China Automotive Energy Research Center (CAERC), Tsinghua University, Beijing 100084 (China); Institute of Energy, Environment and Economy (3E), Tsinghua University, Beijing 100084 (China); Zhang Xiliang, E-mail: zhang_xl@tsinghua.edu.c [China Automotive Energy Research Center (CAERC), Tsinghua University, Beijing 100084 (China); Institute of Energy, Environment and Economy (3E), Tsinghua University, Beijing 100084 (China); Chang Shiyan [China Automotive Energy Research Center (CAERC), Tsinghua University, Beijing 100084 (China); Institute of Energy, Environment and Economy (3E), Tsinghua University, Beijing 100084 (China)

    2010-01-15

    The Chinese government has enacted policies to promote alternative vehicle fuels (AVFs) and alternative fuel vehicles (AFVs), including city bus fleets. The life cycle (LC), energy savings (ES) and GHG reduction (GR) profiles of AVFs/AFVs are critical to those policy decisions. The well-to-wheels module of the Tsinghua-CA3EM model is employed to investigate actual performance data. Compared with conventional buses, AFVs offer differences in performance in terms of both ES and GR. Only half of the AFVs analyzed demonstrate dual benefits. However, all non-oil/gas pathways can substitute oil/gas with coal. Current policies seek to promote technology improvements and market creation initiatives within the guiding framework of national-level diversification and district-level uniformity. Combined with their actual LC behavior and in keeping with near- and long-term strategies, integrated policies should seek to (1) apply hybrid electric technology to diesel buses; (2) encourage NG/LPG buses in gas-abundant cities; (3) promote commercialize electric buses or plug-in capable vehicles through battery technology innovation; (4) support fuel cell buses and hydrogen technology R and D for future potential applications; and (5) conduct further research on boosting vehicle fuel efficiency, applying low-carbon transportation technologies, and addressing all resultant implications of coal-based transportation solutions to human health and natural resources.

  5. Alternative fuel buses currently in use in China. Life-cycle fossil energy use, GHG emissions and policy recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Ou, Xunmin [School of Public Policy and Management (SPPM), Tsinghua University, Beijing 100084 (China); China Automotive Energy Research Center (CAERC), Tsinghua University, Beijing 100084 (China); Institute of Energy, Environment and Economy (3E), Tsinghua University, Beijing 100084 (China); Zhang, Xiliang; Chang, Shiyan [China Automotive Energy Research Center (CAERC), Tsinghua University, Beijing 100084 (China); Institute of Energy, Environment and Economy (3E), Tsinghua University, Beijing 100084 (China)

    2010-01-15

    The Chinese government has enacted policies to promote alternative vehicle fuels (AVFs) and alternative fuel vehicles (AFVs), including city bus fleets. The life cycle (LC), energy savings (ES) and GHG reduction (GR) profiles of AVFs/AFVs are critical to those policy decisions. The well-to-wheels module of the Tsinghua-CA3EM model is employed to investigate actual performance data. Compared with conventional buses, AFVs offer differences in performance in terms of both ES and GR. Only half of the AFVs analyzed demonstrate dual benefits. However, all non-oil/gas pathways can substitute oil/gas with coal. Current policies seek to promote technology improvements and market creation initiatives within the guiding framework of national-level diversification and district-level uniformity. Combined with their actual LC behavior and in keeping with near- and long-term strategies, integrated policies should seek to (1) apply hybrid electric technology to diesel buses; (2) encourage NG/LPG buses in gas-abundant cities; (3) promote commercialize electric buses or plug-in capable vehicles through battery technology innovation; (4) support fuel cell buses and hydrogen technology R and D for future potential applications; and (5) conduct further research on boosting vehicle fuel efficiency, applying low-carbon transportation technologies, and addressing all resultant implications of coal-based transportation solutions to human health and natural resources. (author)

  6. Design Guidelines for Bus Transit Systems Using Liquefied Petroleum Gas (LPG) as an Alternative Fuel.

    Science.gov (United States)

    1996-09-01

    The use of alternative fuels to power transit buses is steadily increasing. Several fuels, including Liquefied Petroleum Gas (LPG), Compressed Natural Gas (CNG), and Methanol/Ethanol, are already being used in buses. At present, there do not exist co...

  7. Mass concentrations of BTEX inside air environment of buses in Changsha, China

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaokai; Zhang, Guoqiang; Zhang, Quan [College of Civil Engineering, Hunan University, Changsha 410082, Hunan (China); Chen, Hong [College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan (China)

    2011-02-15

    In order to estimate the mass concentrations of benzene (B), toluene (T), ethylbenzene (E) and xylenes (X) inside air environment of buses and to analyze the influencing factors of the BTEX pollution levels, 22 public buses were investigated in Changsha, China. The interior air was collected through activated charcoal adsorption tubes and then the air samples were analyzed with thermally desorbed gas chromatograph. The mass concentrations ranged from 21.3 to 106.4 {mu}g/m{sup 3} for benzene, from 53.5 to 266.0 {mu}g/m{sup 3} for toluene, from 19.6 to 95.9 {mu}g/m{sup 3} for ethylbenzene and from 46.9 to 234.8 {mu}g/m{sup 3} for xylenes. Their mean values were 68.7, 179.7, 62.5 and 151.8 {mu}g/m{sup 3}, respectively. The rates of buses tested where the interior concentrations exceeded the limit levels of Chinese Indoor Air Quality Standard were 45.5% for toluene and 13.6% for xylenes. The BTEX levels increased when in-car temperature or relative humidity rose, and decreased when car age or travel distance increased. The BTEX concentrations were higher in leather trims buses than in non-leather trims ones, in air-conditioned buses than in non-air-conditioned ones, and in high-grade buses than in low-grade ones. According to the analysis of multiple linear regression equation, car age and in-car temperature were two most important factors influencing the BTEX pollution levels in the cabins of public buses. (author)

  8. Foothill Transit Battery Electric Bus Demonstration Results

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Prohaska, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kelly, Kenneth [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-01-27

    Foothill Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL) to evaluate its fleet of Proterra battery electric buses (BEBs) in revenue service. The focus of this evaluation is to compare performance of the BEBs to that of conventional technology and to track progress over time toward meeting performance targets. This project has also provided an opportunity for DOE to conduct a detailed evaluation of the BEBs and charging infrastructure. This report provides data on the buses from April 2014 through July 2015. Data are provided on a selection of compressed natural gas buses as a baseline comparison.

  9. Hydrogen for buses in London: A scenario analysis of changes over time in refuelling infrastructure costs

    International Nuclear Information System (INIS)

    Shayegan, S.; Pearson, P.J.G.; Hart, D.

    2009-01-01

    The lack of a hydrogen refuelling infrastructure is one of the major obstacles to the introduction of the hydrogen vehicles to the road transport market. To help overcome this hurdle a likely transitional solution is to introduce hydrogen for niche applications such as buses or other types of fleet vehicles for which fuel demand is predictable and localised. This paper analyses the costs of different hydrogen production-delivery pathways, via a case study of buses in London. Scenario analysis over time (2007-2025) is used to investigate potential changes to the cost of hydrogen as a result of technology development, growing demand for hydrogen and changes in energy prices (gas and electricity). It is found that factors related to hydrogen demand have the greatest effect on the unit cost of hydrogen, while for the whole of the analysis period, on-site SMR (steam methane reforming) remains the least-cost production-delivery pathway. (author)

  10. Fuel Cell Electric Bus Evaluations | Hydrogen and Fuel Cells | NREL

    Science.gov (United States)

    Bus Evaluations Fuel Cell Electric Bus Evaluations NREL's technology validation team evaluates fuel cell electric buses (FCEBs) to provide comprehensive, unbiased evaluation results of fuel cell bus early transportation applications for fuel cell technology. Buses operate in congested areas where

  11. Reliability Evaluation Of The City Transport Buses Under Actual Conditions

    Directory of Open Access Journals (Sweden)

    Rymarz Joanna

    2015-12-01

    Full Text Available The purpose of this paper was to present a reliability comparison of two types of city transport buses. Case study on the example of the well-known brands of city buses: Solaris Urbino 12 and Mercedes-Benz 628 Conecto L used at Municipal Transport Company in Lublin was presented in details. A reliability index for the most failure parts and complex systems for the period of time failures was determined. The analysis covered damages of the following systems: engine, electrical system, pneumatic system, brake system, driving system, central heating and air-conditioning and doors. Reliability was analyzed based on Weibull model. It has been demonstrated, that during the operation significant reliability differences occur between the buses produced nowadays.

  12. Current Leads, Links and Buses

    CERN Document Server

    Ballarino, A

    2014-01-01

    Electrical transfer from a room temperature power source to a superconducting system is done via conventional or superconducting current leads and superconducting buses or links. The principles of optimization of these devices are presented, with emphasis on the cryogenic, electrical, and superconductor related aspects that drive choices for a system.

  13. Current Leads, Links and Buses

    Energy Technology Data Exchange (ETDEWEB)

    Ballarino, A [European Organization for Nuclear Research, Geneva (Switzerland)

    2014-07-01

    Electrical transfer from a room temperature power source to a superconducting system is done via conventional or superconducting current leads and superconducting buses or links. The principles of optimization of these devices are presented, with emphasis on the cryogenic, electrical, and superconductor related aspects that drive choices for a system.

  14. Progress in hydrogen fueled busses

    International Nuclear Information System (INIS)

    Scott, P.B.; Mazaika, D.M.; Tyler, T.

    2004-01-01

    'Full text:' The Thor/ISE fuel cell bus has been in demonstration and revenue service during 2002-2003 at sites including SunLine Transit, Chula Vista Transit, Los Angeles County Metropolitan Transit Authority, and AC Transit in Oakland. By taking advantage of ISE's advanced hybrid-electric drive technology, this 30-foot bus operates with a much smaller fuel cell than those used in other buses of this class. Further, stress on the fuel cell is diminished. Based on the exceptional performance of this prototype bus, the transit agencies listed above have concluded that hybrid electric hydrogen fueled buses are attractive. Two types of hydrogen fueled hybrid electric buses will be described: - fuel cell powered, and - HICE (Hydrogen Internal Combustion Engine) This progress report will include: 1. Experience with the Thor/ISE fuel cell bus, including results from revenue service at two transit locations, 2. Design and fabrication status of the advanced fuel cell buses being built for AC Transit and SunLine Transit, 3. Design and fabrication status of the prototype HHICE (Hybrid electric Hydrogen fueled Internal Combustion Engine) bus that uses a Ford hydrogen burning engine, mated to a generator, rather than a fuel cell. Other than the engine, the drive train in the HHICE bus is nearly identical to that of a fuel cell hybrid-electric bus. Canadian participation in the HHICE bus is extensive, it is a New Flyer platform and will be winter tested in Winnipeg. (author)

  15. Characterizing ultrafine particles and other air pollutants in and around school buses.

    Science.gov (United States)

    Zhu, Yifang; Zhang, Qunfang

    2014-03-01

    Increasing evidence has demonstrated toxic effects of ultrafine particles (UFP*, diameter emissions from idling school buses to air pollutant levels in and around school buses under different scenarios; 3. Retrofit tests to evaluate the performance of two retrofit systems, a diesel oxidation catalyst (DOC) muffler and a crankcase filtration system (CFS), on reducing tailpipe emissions and in-cabin air pollutant concentrations under idling and driving conditions; and 4. High efficiency particulate air (HEPA) filter air purifier tests to evaluate the effectiveness of in-cabin filtration. In total, 24 school buses were employed to cover a wide range of school buses commonly used in the United States. Real-time air quality measurements included particle number concentration (PNC), fine and UFP size distribution in the size range 7.6-289 nm, PM2.5 mass concentration, black carbon (BC) concentration, and carbon monoxide (CO) and carbon dioxide (CO2) concentrations. For in-cabin measurements, instruments were placed on a platform secured to the rear seats inside the school buses. For all other tests, a second set of instruments was deployed to simultaneously measure the ambient air pollutant levels. For tailpipe emission measurements, the exhaust was diluted and then measured by instruments identical to those used for the in-cabin measurements. The results show that when driving on roads, in-cabin PNC, fine and UFP size distribution, PM2.5, BC, and CO varied by engine age, window position, driving speed, driving route, and operating conditions. Emissions from idling school buses increased the PNC close to the tailpipe by a factor of up to 26.0. Under some circumstances, tailpipe emissions of idling school buses increased the in-cabin PNC by factors ranging from 1.2 to 5.8 in the 10-30 nm particle size range. Retrofit systems significantly reduced the tailpipe emissions of idling school buses. With both DOC and CFS installed, PNC in tailpipe emissions dropped by 20

  16. Measurements of ultrafine particles and other vehicular pollutants inside school buses in South Texas

    Science.gov (United States)

    Zhang, Qunfang; Zhu, Yifang

    2010-01-01

    Increasing evidence has demonstrated toxic effects of vehicular emitted ultrafine particles (UFPs, diameter pollutants, especially UFPs, was measured inside four diesel-powered school buses. Two 1990 and two 2006 model year diesel-powered school buses were selected to represent the age extremes of school buses in service. Each bus was driven on two routine bus runs to study school children's exposure under different transportation conditions in South Texas. The number concentration and size distribution of UFPs, total particle number concentration, PM 2.5, PM 10, black carbon (BC), CO, and CO 2 levels were monitored inside the buses. The average total particle number concentrations observed inside the school buses ranged from 7.3 × 10 3 to 3.4 × 10 4 particles cm -3, depending on engine age and window position. When the windows were closed, the in-cabin air pollutants were more likely due to the school buses' self-pollution. The 1990 model year school buses demonstrated much higher air pollutant concentrations than the 2006 model year ones. When the windows were open, the majority of in-cabin air pollutants came from the outside roadway environment with similar pollutant levels observed regardless of engine ages. The highest average UFP concentration was observed at a bus transfer station where approximately 27 idling school buses were queued to load or unload students. Starting-up and idling generated higher air pollutant levels than the driving state. Higher in-cabin air pollutant concentrations were observed when more students were on board.

  17. The Bus Stops Here: The Case for Biodiesel in School Buses.

    Science.gov (United States)

    Rao, Steven T.

    2002-01-01

    Suggests that diesel exhaust from most of the nation's school buses may be hazardous to children's health. Documents studies on the nature and potential magnitude of the risk to children and proposes replacing petroleum diesel with biodiesel as the fuel for school buses. Presents the merits and practicality of switching to biodiesel as a healthier…

  18. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2008

    Science.gov (United States)

    2008-12-01

    In September 2007, the U.S. Department of Energys (DOE) National Renewable Energy Laboratory (NREL) published a report that reviewed past and present fuel cell bus technology development and implementation in the United States. That report reviewe...

  19. Charging cost optimization for EV buses using neural network based energy predictor

    NARCIS (Netherlands)

    Nageshrao, S.P.; Jacob, J.; Wilkins, S.

    2017-01-01

    For conventional buses, based on the decades of their operational knowledge, public transport companies are able to optimize their cost of operation. However, with recent trend in the usage of electric buses, cost optimal operation can become challenging. In this paper an offline optimal charging

  20. Operational Assessment of Paralympics Transit Systems : Low-Floor Buses, Lift-Equipped Buses, and Signage

    Science.gov (United States)

    1997-02-01

    From August 15-25, Atlanta hosted the paralympics, a world-class athletic competition for athletes with disabilities. To support the Paralympics, a specialized transit service was planned and deployed to service the travel needs of athletes, trainers...

  1. On the issue of selecting technical and operational parameters for buses in urban passenger routes

    Directory of Open Access Journals (Sweden)

    Rudzinskyi V.V.

    2017-10-01

    Full Text Available Problems of a public transport bus service in urban areas were analyzed. The aim of the article is to determine actual operational parameters of buses during passenger transportation in Zhytomyr. Ways of determining technical and operational parameters of buses were developed using visual and tabular methods of city buses real-time speed and acceleration performance registration by GPS-monitoring system with the help of a communicational and informational intelligent transport system of the city. Experimental studies of city buses motion parameters were presented. A comprehensive survey of passenger traffic and conditions of public transport functioning in Zhytomyr was carried out. The values of technical and operational parameters of buses on city routes were obtained. Preliminarily conclusions and recommendations considering the criteria for selecting the optimal rolling stock for a bus network of the city were suggested.

  2. The New Energy Buses in China

    DEFF Research Database (Denmark)

    Wang, Jingyu; Liu, Yingqi; Kokko, Ari

    2013-01-01

    With the advent of “low carbon” economy, new energy vehicles are increasingly favored by the Chinese government and manufacturers. New energy buses have become an important channel for the promotion of new energy utilizations. Based on the summary of policies, this paper conducts a thorough...

  3. URBAN PUBLIC TRANSPORT WITH THE USE OF ELECTRIC BUSES – DEVELOPMENT TENDENCIES

    Directory of Open Access Journals (Sweden)

    Stanisław KRAWIEC

    2016-12-01

    Full Text Available The programing documents of the European Union determine the direction of transport systems development, including large cities and agglomerations. The context of these actions which aim to transform into ecologically clean and sustainable transport system is a significant reduction of greenhouse gas emissions. Assuming that public transport will significantly reduce the use of combustion-powered buses, studies on urban logistic enabling the use of electric buses for public transport are needed. The article presents the variants and scenarios for electric buses implementation in urban public transport, as well as the decision algorithm to support electric bus implementation based on technological, organisational, economic and ecological variables.

  4. Bacterial Quality of Drinking Water in Bushehr Intercity Buses in 2010

    Directory of Open Access Journals (Sweden)

    Dariush Ranjbar Vakilabadi

    2012-12-01

    Full Text Available Background and Objective: Road transportation and specifically bus travel accounts for the bulk of travel. Contaminated drinking water consumption is one of the issues that threaten health, and always there is pollution possibility in drinking water in buses. This study evaluated the microbial quality of consumed drinking water in buses and also compared it with available standards. Materials and Methods: This study is a cross-sectional study. By considering similar studies, 95% confidence interval and based on the samples size formula for tradition of proportion, 80 buses from 122 buses that entered Bushehr Passenger Depot from other cities or exited it were randomly selected. Over a three-month period, samples were taken from drinking water in these buses. Temperature, pH, residual chlorine, total coliform (TC, and fecal coliform (E. coli in each sample were measured in accordance with the standard method. Statistical analysis of the data was carried out with SPSS Version 16, and the t-test was performed for statistical difference. Results: The results showed that residual chlorine in 97.5% was zero and pH values of the samples were in the range of 6.8-8.7. TC and E. coli numbers in 12.5% and 8.8% of the samples were higher than those of standards, respectively. Conclusion: Use of ice, washing time of the drinking water tank (daily or weekly, and method of usage and storage of drinking water (with 20-liter tanks had significant effects on the bacterial loads of the drinking water in the tanks (p value <0.05. Some factors such as tank material, driver's education and age, type and model of the bus, filling time of the tank (daily or weekly, the method of filling and emptying the tank (complete clearing out of the tank or otherwise, and distance had no significant effect on the quality of the drinking water in the buses.

  5. Studies of self-pollution in diesel school buses: methodological issues.

    Science.gov (United States)

    Borak, Jonathan; Sirianni, Greg

    2007-09-01

    Considerable interest has focused on levels of exhaust emissions in the cabins of diesel-powered school buses and their possible adverse health effects. Significantly different policy and engineering issues would be raised if compelling evidence found that inc-cabin contamination was due to self-pollution from bus emissions, rather than ambient pollution, neighboring vehicles, and/or re-entrained road dust. We identified 19 reports from 11 studies that measured diesel exhaust particulate in the cabins of 58 school bus of various type. Studies were evaluated in light of their experimental design, their data quality, and their capacity to quantify self-pollution. Only one study had a true experimental design, comparing the same buses with and without emission controls, while four others used intentional tracers to quantify tail pipe and/or crankcase emissions. Although definitive data are still lacking, these studies suggest that currently available control technologies can nearly eliminate particulate self-pollution inside diesel school buses.

  6. A Framework for Assessing Feasibility of Transit-Oriented Development (TOD) Project Sites

    Science.gov (United States)

    2017-09-01

    After the Second World War, the United States saw a decline in ridership on transit systems, which eventually resulted in the dismantling and abandonment of many rail systems. The primary mode of public transportation shifted from transit to buses. I...

  7. Environmental benefits of natural gas for buses

    International Nuclear Information System (INIS)

    Rabl, A.

    2002-01-01

    This paper presents a life cycle assessment comparing diesel buses with buses fueled by natural gas. The data for the emission of pollutants are based on the MEET Project of the European Commission (EC), supplemented by data measured for diesel and gas buses in Paris. The benefits of the gas fueled bus are then quantified using the damage cost estimates of the ExternE Project of the EC. A diesel bus with emissions equal to Standard EURO2 of the EC is compared with the same bus equipped with a natural gas engine, for use in Paris and in Toulouse. The damage cost of a diesel bus is significant, in the range of 0.4-1.3 euro/km. Natural gas allows an appreciable reduction of the emissions, lowering the damage cost by a factor of about 2.5 (Toulouse) to 5.5 (Paris). An approximate rule is provided for transferring the results to other cities. A sensitivity analysis is carried out to evaluate the effect of the evolution of the emissions standard towards EURO3, 4 and 5, as well as the effect of uncertainties. Finally a comparison is presented between a EURO2 diesel bus with particle filter, and a gas fueled bus with the MPI engine of IVECO, a more advanced and cleaner technology. With this engine the damage costs of the gas fueled bus are about 3-5 times lower than those of the diesel with particle filter, even though the latter has already very low emissions.(author)

  8. Unit Monitors Manchester-Format Data Buses

    Science.gov (United States)

    Amador, Jose J.

    1994-01-01

    Circuit card converts data signals into convenient hexadecimal form for troubleshooting. Bus-monitoring unit converts data signals from Manchester II format used on data bus into hexadecimal format. Monitoring circuit causes hexadecimal words to display on video terminal, where test engineer compares them with hexadecimal records for troubleshooting. Circuit monitors one bus or two buses simultaneously.

  9. Cool Science: K-12 Climate Change Art Displayed on Buses

    Science.gov (United States)

    Chen, R. F.; Lustick, D. S.; Lohmeier, J.; Thompson, S. R.

    2015-12-01

    Cool science is an art contest where K12 students create placards (7" x 22") to educate the public about climate change. Students are prompted to create their artwork in response to questions such as: What is the evidence for climate change? How does climate change impact your local community? What can you do to reduce the impacts of climate change? In each of three years, 500-600 student entrees have been submitted from more than 12 school districts across Massachusetts. A panel of judges including scientists, artists, rapid transit representatives, and educators chooses elementary, middle, and high school winners. Winners (6), runners-up (6), and honorable mentions (12) and their families and teachers are invited to an annual Cool Science Award Ceremony to be recognized and view winning artwork. All winning artwork is posted on the Cool Science website. The winning artwork (2 per grade band) is converted into placards (11" x 28") and posters (2.5' x 12') that are placed on the inside (placards) and outside (posters) of buses. Posters are displayed for one month. So far, Cool Science was implemented in Lowell, MA where over 5000 public viewers see the posters daily on the sides of Lowell Rapid Transit Authority (LRTA) buses, making approximately 1,000,000 impressions per year. Cool Science acts to increase climate literacy in children as well as the public, and as such promotes intergenerational learning. Using art in conjunction with science learning about climate change appears to be effective at engaging not just traditionally high achieving science students, but also those interested in the creative arts. Hearing winners' stories about how they created their artwork and what this contest meant to them supports the idea that Cool Science attracts a wide diversity of students. Parents discuss climate change with their children. Multiple press releases announcing the winners further promotes the awareness of climate change throughout school districts and their

  10. Using Task Clarification, Goal Setting, and Feedback to Decrease Table Busing Times in a Franchise Pizza Restaurant

    Science.gov (United States)

    Amigo, Seth; Smith, Andrew; Ludwig, Timothy

    2008-01-01

    The current study investigated the effects of task-clarification, and manager verbal and graphic feedback on employee busing times at a pizza restaurant. Using an ABC design, task-clarification was provided in a memo, which described the process, priority, and goal time of busing. The busing time decreased slightly, from an average of 315 seconds…

  11. COMPARATIVE STUDY ON EXHAUST EMISSIONS FROM DIESEL- AND CNG-POWERED URBAN BUSES

    Energy Technology Data Exchange (ETDEWEB)

    COROLLER, P; PLASSAT, G

    2003-08-24

    Couple years ago, ADEME engaged programs dedicated to the urban buses exhaust emissions studies. The measures associated with the reduction of atmospheric and noise pollution has particular importance in the sector of urban buses. In many cases, they illustrate the city's environmental image and contribute to reinforcing the attractiveness of public transport. France's fleet in service, presently put at about 14,000 units, consumes about 2 per cent of the total energy of city transport. It causes about 2 per cent of the HC emissions and from 4 to 6 per cent of the NOx emissions and particles. These vehicles typically have a long life span (about 15 years) and are relatively expensive to buy, about 150.000 euros per unit. Several technical solutions were evaluated to quantify, on a real condition cycle for buses, on one hand pollutants emissions, fuel consumption and on the other hand reliability, cost in real existing fleet. This paper presents main preliminary results on urban buses exhaust emission on two different cases: - existing Diesel buses, with fuel modifications (Diesel with low sulphur content), Diesel with water emulsion and bio-Diesel (30% oil ester in standard Diesel fuel); renovating CNG powered Euro II buses fleet, over representative driving cycles, set up by ADEME and partners. On these cycles, pollutants (regulated and unregulated) were measured as well as fuel consumption, at the beginning of a program and one year after to quantify reliability and increase/decrease of pollutants emissions. At the same time, some after-treatment technologies were tested under real conditions and several vehicles. Information such as fuel consumption, lubricant analysis, problem on the technology were following during a one year program. On the overall level, it is the combination of various action, pollution-reduction and renewal that will make it possible to meet the technological challenge of reducing emissions and fuel consumption by urban bus

  12. Foothill Transit Battery Electric Bus Demonstration Results: Second Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jeffers, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-06-28

    This report summarizes results of a battery electric bus (BEB) evaluation at Foothill Transit, located in the San Gabriel and Pomona Valley region of Los Angeles County, California. Foothill Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory to evaluate its fleet of Proterra BEBs in revenue service. The focus of this evaluation is to compare performance of the BEBs to that of conventional technology and to track progress over time toward meeting performance targets. This project has also provided an opportunity for DOE to conduct a detailed evaluation of the BEBs and charging infrastructure. This is the second report summarizing the results of the BEB demonstration at Foothill Transit and it provides data on the buses from August 2015 through December 2016. Data are provided on a selection of compressed natural gas buses as a baseline comparison.

  13. Developing a discrete event simulation model for university student shuttle buses

    Science.gov (United States)

    Zulkepli, Jafri; Khalid, Ruzelan; Nawawi, Mohd Kamal Mohd; Hamid, Muhammad Hafizan

    2017-11-01

    Providing shuttle buses for university students to attend their classes is crucial, especially when their number is large and the distances between their classes and residential halls are far. These factors, in addition to the non-optimal current bus services, typically require the students to wait longer which eventually opens a space for them to complain. To considerably reduce the waiting time, providing the optimal number of buses to transport them from location to location and the effective route schedules to fulfil the students' demand at relevant time ranges are thus important. The optimal bus number and schedules are to be determined and tested using a flexible decision platform. This paper thus models the current services of student shuttle buses in a university using a Discrete Event Simulation approach. The model can flexibly simulate whatever changes configured to the current system and report its effects to the performance measures. How the model was conceptualized and formulated for future system configurations are the main interest of this paper.

  14. Concentrations of volatile organic compounds, carbon monoxide, carbon dioxide and particulate matter in buses on highways in Taiwan

    Science.gov (United States)

    Hsu, Der-Jen; Huang, Hsiao-Lin

    2009-12-01

    Although airborne pollutants in urban buses have been studied in many cities globally, long-distance buses running mainly on highways have not been addressed in this regard. This study investigates the levels of volatile organic compounds (VOCs), carbon monoxide (CO), carbon dioxide (CO 2) and particulate matter (PM) in the long-distance buses in Taiwan. Analytical results indicate that pollutants levels in long-distance buses are generally lower than those in urban buses. This finding is attributable to the driving speed and patterns of long-distance buses, as well as the meteorological and geographical features of the highway surroundings. The levels of benzene, toluene, ethylbenzene and xylene (BTEX) found in bus cabins exceed the proposed indoor VOC guidelines for aromatic compounds, and are likely attributable to the interior trim in the cabins. The overall average CO level is 2.3 ppm, with higher average level on local streets (2.9 ppm) than on highways (2.2 ppm). The average CO 2 level is 1493 ppm, which is higher than the guideline for non-industrial occupied settings. The average PM level in this study is lower than those in urban buses and IAQ guidelines set by Taiwan EPA. However, the average PM 10 and PM 2.5 is higher than the level set by WHO. Besides the probable causes mentioned above, fewer passenger movements and less particle re-suspension from bus floor might also cause the lower PM levels. Measurements of particle size distribution reveal that more than 75% of particles are in submicron and smaller sizes. These particles may come from the infiltration from the outdoor air. This study concludes that air exchange rates in long-distance buses should be increased in order to reduce CO 2 levels. Future research on long-distance buses should focus on the emission of VOCs from brand new buses, and the sources of submicron particles in bus cabins.

  15. Confusion errors and false manoeuvres at power buses

    International Nuclear Information System (INIS)

    Cernes, A.

    1985-09-01

    The incident at Bugey 5 on 14th April 1984, which is regarded as one of the most important in recent years has alas shown again that unless dealt with by the operators in good time, failure of a rectifier supplying one of the buses may soon lead to a very serious situation, in this particular instance voltage loss on the train A 48 volt supply from the two offsite electrical sources and train A diesel generator. Operating experience feedback of the past three years reveals that although the Bugey incident is undoubtedly the most serious, it is not the only where a major alarm was not taken into consideration until fairly late by the operators, and other types of error with far from negligible consequences have occurred during repair work on buses. After a brief reminder of the role and layout of buses, statistics of all incidents of this type in recent years are described and a few cases are presented in order to give some idea of the range of situations encountered. The main measures aimed at reducing the number of incidents of this type are then presented, bearing in mind that one cannot hope to remove the possibility of this type of failure entirely. It may also be noted that the large number of such errors during the night shift or at the very beginning of the morning shift is no doubt connected with the well-known fact that operators are less vigilant at such times

  16. Environmental impact assessment of bus rapid transit (BRT in the Metropolitan City of Tehran

    Directory of Open Access Journals (Sweden)

    F. Salehi

    2016-01-01

    Full Text Available Bus rapid transit is an innovative, high capacity, lower cost public transit solution in metropolitan cities. Idea is to dedicate lanes for quick and efficient transport of passengers to their destinations. In the present investigation the environmental impact assessment of bus rapid transit  in Tehran metropolitan city is brought out. For this purpose bus rapid transit Lane No. 10 is investigated. The bus rapid transit Lane No.10 is about 10 km in distance that moves up and down between Azadi and Simon Bolivar Squares. About 77500 passengers using 50 buses are transited per day in lane No. 10. These 50 buses cover a distance of 9600 km/day. The results of present study showed that about 6.5 million liters of fuel is saved annually. It should be pointed out that environmental costs are also reduced for about US$ 1.7 million/yr. The overall score of environmental impact assessment stands at +10 that is indicative of Lane No. 10 compatibility with the environmental considerations.

  17. Assessment of alternative fuel and powertrain transit bus options using real-world operations data: Life-cycle fuel and emissions modeling

    International Nuclear Information System (INIS)

    Xu, Yanzhi; Gbologah, Franklin E.; Lee, Dong-Yeon; Liu, Haobing; Rodgers, Michael O.; Guensler, Randall L.

    2015-01-01

    applies the FEC to second-by-second GPS position data collected from buses operating in metropolitan Atlanta, GA. These operations, from two different transit agencies, feature distinctly different transit service types: local transit bus operations and longer-distance express bus operations. The results illustrate that the decision as to which bus technology-fuel combination produces the least greenhouse gas emissions is a function of location and route characteristics. For the express bus operations monitored, the case study shows that CNG vehicles offer greater emissions reductions than Biodiesel (B20). For local bus services, battery electric buses show the greatest emissions savings in the fuel cycle, as long as range limitations can be met for the specific routes. The amount of these emissions savings is, however, highly dependent on the power generation mix. Among CNG, B20, parallel hybrid, series hybrid, and fuel cell buses, the least emitting option varies by location, due to complex interactions of factors such as duty cycle, meteorology, and terrain

  18. Multistage Mechanical Transmissions with Automatic Control for Advanced Trucks and Buses

    Directory of Open Access Journals (Sweden)

    Blokhin Aleksandr

    2017-12-01

    Full Text Available The study considers the basic trends of development of modern mechanical transmissions of trucks and buses. It provides the developed various series of multispeed transmissions with automatic control and a number of transmissions from 6 to 16 for trucks and buses. The paper shows the basic parameters of the standard series of new transmissions received on the basis of innovative technical solutions. It provides the results of experimental studies of 16-speed transmissions on a special test stand and on the road as part of a truck transmission. Theoretical and experimental data on the gear change time are compared.

  19. Feasibility study on the introduction of hybrid buses; Hybrid bus donyu kanosei chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The purpose of this research is to design pilot projects for introducing hybrid buses into the public transportation sector. This research also covers contents regarding hybrid buses with a trolley-collector motor and a diesel engine, to identify technical and economical problems and to analyze cost beneficiation using hybrid buses. The trolley parallel hybrid system has been employed for the feasibility study. This system has abundant operation results in Europe and the USA. Its battery is small or is not necessary, and the maintenance cost is also low. As a result of the feasibility study, reduction effects of CO2 emission were found out. When the CO2 generation at the power plant is not counted, the reduction effect was estimated to be 32% compared with the CO2 emission from diesel buses. When the CO2 generation at the power plant is considered, it was estimated to be 18%. The cost beneficiation was investigated for the cases of the transportations using trolley system surrounding a medium-scale terminal among large-scale housing development, tourist resort, and stations. The annual income is estimated to be larger than the annual payment in each case. It was found that the hybrid bus is economically established. 17 refs., 48 figs., 41 tabs.

  20. Carbon Dioxide Concentrations and Temperatures within Tour Buses under Real-Time Traffic Conditions

    Science.gov (United States)

    Chiu, Chun-Fu; Chen, Ming-Hung; Chang, Feng-Hsiang

    2015-01-01

    This study monitored the carbon dioxide (CO2) concentrations and temperatures of three 43-seat tour buses with high-passenger capacities in a course of a three-day, two-night school excursion. Results showed that both driver zones and passenger zones of the tour buses achieved maximum CO2 concentrations of more than 3000 ppm, and maximum daily average concentrations of 2510.6 and 2646.9 ppm, respectively. The findings confirmed that the CO2 concentrations detected in the tour buses exceeded the indoor air quality standard of Taiwan Environmental Protection Administration (8 hr-CO2: 1000 ppm) and the air quality guideline of Hong Kong Environmental Protection Department (1 hr-CO2: 2500 ppm for Level 1 for buses). Observations also showed that high-capacity tour bus cabins with air conditioning system operating in recirculation mode are severely lacking in air exchange rate, which may negatively impact transportation safety. Moreover, the passenger zones were able to maintain a temperature of between 20 and 25°C during travel, which effectively suppresses the dispersion of volatile organic compounds. Finally, the authors suggest that in the journey, increasing the ventilation frequency of tour bus cabin, which is very beneficial to maintain the travel safety and enhance the quality of travel. PMID:25923722

  1. Carbon Dioxide Concentrations and Temperatures within Tour Buses under Real-Time Traffic Conditions.

    Science.gov (United States)

    Chiu, Chun-Fu; Chen, Ming-Hung; Chang, Feng-Hsiang

    2015-01-01

    This study monitored the carbon dioxide (CO2) concentrations and temperatures of three 43-seat tour buses with high-passenger capacities in a course of a three-day, two-night school excursion. Results showed that both driver zones and passenger zones of the tour buses achieved maximum CO2 concentrations of more than 3000 ppm, and maximum daily average concentrations of 2510.6 and 2646.9 ppm, respectively. The findings confirmed that the CO2 concentrations detected in the tour buses exceeded the indoor air quality standard of Taiwan Environmental Protection Administration (8 hr-CO2: 1000 ppm) and the air quality guideline of Hong Kong Environmental Protection Department (1 hr-CO2: 2500 ppm for Level 1 for buses). Observations also showed that high-capacity tour bus cabins with air conditioning system operating in recirculation mode are severely lacking in air exchange rate, which may negatively impact transportation safety. Moreover, the passenger zones were able to maintain a temperature of between 20 and 25°C during travel, which effectively suppresses the dispersion of volatile organic compounds. Finally, the authors suggest that in the journey, increasing the ventilation frequency of tour bus cabin, which is very beneficial to maintain the travel safety and enhance the quality of travel.

  2. Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration: Second Results Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.

    2012-07-01

    This report presents results of a demonstration of 12 new fuel cell electric buses (FCEB) operating in Oakland, California. The 12 FCEBs operate as a part of the Zero Emission Bay Area (ZEBA) Demonstration, which also includes two new hydrogen fueling stations. This effort is the largest FCEB demonstration in the United States and involves five participating transit agencies. The ZEBA partners are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service. The first results report was published in August 2011, describing operation of these new FCEBs from September 2010 through May 2011. New results in this report provide an update through April 2012.

  3. Quantitative characterization of the reliability of simplex buses and stars to compare their benefits in fieldbuses

    International Nuclear Information System (INIS)

    Barranco, Manuel; Proenza, Julián; Almeida, Luís

    2015-01-01

    Fieldbuses targeted to highly dependable distributed embedded systems are shifting from bus to star topologies. Surprisingly, despite the efforts into this direction, engineers lack of analyses that quantitatively characterize the system reliability achievable by buses and stars. Thus, to guide engineers in developing adequate bus and star fieldbuses, this work models, quantifies and compares the system reliability provided by simplex buses and stars for the case of the Controller Area Network (CAN). It clarifies how relevant dependability-related aspects affect reliability, refuting some intuitive ideas, and revealing some previously unknown bus and star benefits. - Highlights: • SANs models that quantify the reliability of simplex buses/stars in fieldbuses. • Models cover system relevant dependability-related features abstracted in the literature. • Results refute intuitive ideas about buses and stars and show some unexpected effects. • Models and results can guide the design of reliable simplex bus/stars fieldbuses

  4. Evaluation of retrofit crankcase ventilation controls and diesel oxidation catalysts for reducing air pollution in school buses

    Science.gov (United States)

    Trenbath, Kim; Hannigan, Michael P.; Milford, Jana B.

    2009-12-01

    This study evaluates the effect of retrofit closed crankcase ventilation filters (CCFs) and diesel oxidation catalysts (DOCs) on the in-cabin air quality in transit-style diesel school buses. In-cabin pollution levels were measured on three buses from the Pueblo, CO District 70 fleet. Monitoring was conducted while buses were driven along their regular routes, with each bus tested three times before and three times after installation of control devices. Ultrafine number concentrations in the school bus cabins were 33-41% lower, on average, after the control devices were installed. Mean mass concentrations of particulate matter less than 2.5 μm in diameter (PM2.5) were 56% lower, organic carbon (OC) 41% lower, elemental carbon (EC) 85% lower, and formaldehyde 32% lower after control devices were installed. While carbon monoxide concentrations were low in all tests, mean concentrations were higher after control devices were installed than in pre-retrofit tests. Reductions in number, OC, and formaldehyde concentrations were statistically significant, but reductions in PM2.5 mass were not. Even with control devices installed, during some runs PM2.5 and OC concentrations in the bus cabins were elevated compared to ambient concentrations observed in the area. OC concentrations inside the bus cabins ranged from 22 to 58 μg m -3 before and 13 to 33 μg m -3 after control devices were installed. OC concentrations were correlated with particle-bound organic tracers for lubricating oil emissions (hopanes) and diesel fuel and tailpipe emissions (polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons). Mean concentrations of hopanes, PAH, and aliphatic hydrocarbons were lower by 37, 50, and 43%, respectively, after the control devices were installed, suggesting that both CCFs and DOCs were effective at reducing in-cabin OC concentrations.

  5. School buses, air pollution and children's health: follow-up report

    International Nuclear Information System (INIS)

    Perrotta, K.

    2010-10-01

    This document is designed to be a follow-up report to the Ontario Public Health Association (OPHA) school bus report published in 2005, and was produced through a collaboration between the Clean Air Partnership and the OPHA. The level of awareness of school bus emissions are evaluated in this report. The document also provides a review of projects handled by the federal government, programs developed by governments of other provinces and the policies followed by school boards in other provinces, to mitigate emissions and exposures related to school buses. Several recommendations were made, including the replacement of older school buses, adapt the routes considering the emissions generated and promote the use of biodiesel to reduce emissions of air pollutants and greenhouse gases. 36 refs, 8 tabs.

  6. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2008-10-01

    This report provides preliminary results from a National Renewable Energy Laboratory evaluation of a protoptye fuel cell transit bus operating at Connecticut Transit in Hartford. Included are descriptions of the planned fuel cell bus demonstration and equipment; early results and agency experience are also provided.

  7. Methicillin-resistant Staphylococcus aureus in public transportation vehicles (buses): another piece to the epidemiologic puzzle.

    Science.gov (United States)

    Lutz, Jonathan K; van Balen, Joany; Crawford, John Mac; Wilkins, John R; Lee, Jiyoung; Nava-Hoet, Rocio C; Hoet, Armando E

    2014-12-01

    Little is known about the occurrence and epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in public transportation in the United States. This research sought to determine the background prevalence and phenotypic and genotypic characteristics of MRSA strains circulating on buses from a large, metropolitan transportation agency. Electrostatic wipes were used to collect 237 surface samples from 40 buses randomly selected from July-October 2010. Six samples were collected from each bus immediately postservice and before any cleaning and disinfection. Positive isolates were analyzed for antibiotic resistance, staphylococcal cassette chromosome mec (SCCmec) type, and pulsed-field gel electrophoresis; and potential epidemiologic factors were examined. Of the buses, 68% (27/40) were contaminated with S aureus, and 63% (25/40) were contaminated with MRSA. Seats and seat rails were the surfaces most frequently contaminated, followed by the back door and stanchions. Most (62.9%) of the MRSA isolates were classified as community-associated MRSA clones (SCCmec type IV), and 22.9% were health care-associated MRSA clones (SCCmec type II). Of the MRSA strains, 65% (5/20) were multidrug resistant. MRSA was frequently isolated from commonly touched surfaces in buses serving both hospital and community routes. Phenotypic and genotypic analysis demonstrated that buses may be effective mixing vessels for MRSA strains of both community and health care-associated origin. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  8. The impact of transit signal priority: case study in Dubai, UAE

    Directory of Open Access Journals (Sweden)

    Al Khateeb Hadeel

    2017-01-01

    Full Text Available Abdulfatah & Alkhateeb proposes on this paper one of the Intelligent Transportation Systems- ITS, the Transit Signal Priority- TSP, which involves real time tracking. The United States is considered one of the lead countries in implementing this strategy since decades ago. Europe and Germany have also implemented TSP quite extensively to improve rider-ship and buses efficiency. TSP is a strategy that supports the transit system through easing the movement of the service. The operational technique used for TSP is controlling the signal system at the intersections. A detector system must be integrated in the implementation stage. It will detect the preference of public buses among the other vehicles in the traffic queue. Determining of optimal detector location for the TSP with queued lanes is the main feature. It must be studied and decided on before starting different signalization proposals for the intersection. Controlling traffic signal in favor of the public bus system will improve reliability and efficiency for buses. Meanwhile, the extreme impact of the TSP on general traffic as well as on public buses became the basis for many recent studies and thesis tested by many authors. The scope of the project as addressed in this paper is to report the delivered results of different scenarios tested, and then compare these proposed scenarios to select the best signal consideration, which has a potential impact on bus and traffic performance. After applying TSP, the results show that the impact of actuating traffic signals in Al Mussallah / Al Maktoum corridor after extending green time for bus approach (15 sec through minimum reduction on average travel time for busses by 7.04%and tremendous increase in travel time for cars by 38.68%. A reduction in cars Avg. Speed by 28.04% in comparison to 35.52% buses Avg. Speed. On the other hand, a reduction in buses delay received by 14.11% and a decrease in Avg. Stopped delay per bus of about 18.56%, while

  9. Concentrations and risk assessment of selected monoaromatic hydrocarbons in buses and bus stations of Hangzhou, China.

    Science.gov (United States)

    Li, Shuang; Chen, Shuguang; Zhu, Lizhong; Chen, Xiasheng; Yao, Chaoying; Shen, Xueyou

    2009-03-01

    Air pollution surveys of ten selected monoaromatic hydrocarbons (MAHCs) were conducted in buses and bus stations in Hangzhou, China. The mean concentrations of MAHCs in the air of buses and bus stations were 95.9 and 36.5 microg/m(3), respectively, of which toluene was the highest in all the sampling sites. Mean concentrations of all MAHCs in buses were statistically higher than those nearby bus stations (pbus drivers were 1.11x10(-5) and 4.00x10(-5), respectively, which were way above the limit set by USEPA. The health risk caused by MAHCs in bus microenvironment should be cautioned.

  10. Efficiency evaluation of gas fuelled and electric driven buses in the public transport sector

    Energy Technology Data Exchange (ETDEWEB)

    Aigner, Tobias Alexander

    2013-07-01

    The following report evaluates the efficiency of gas fuelled and electric driven buses in the public transport sector on a theoretical basis. The results indicate that the combination of CHP power plants and electric driven buses reach an overall efficiency of about 51% throughout the production chain (Well-to-Wheel), including heat distribution losses. The overall Well-to-Wheel efficiency for conventional gas turbines without heat recovery decreases to around 28%. For gas fuelled buses the Well-to-Wheel efficiency is about 30%. The Co2-emissions are evaluated based on the example of a #Left Double Quotation Mark#Volvo B10L CNG#Right Double Quotation Mark# gas bus and the electric driven #Left Double Quotation Mark#Eurabus 600#Right Double Quotation Mark#. The low energy consumption of the electric driven bus results in Co2-emissions of only 181.4 g Co2/km (Grid-to-Wheel). Depending on the utilised power plant technology the overall Co2-emissions (Well-to-Wheel) amount to 307.5 g Co2/km for a CHP power plant and 553.5 g Co2/km for a conventional gas turbine. On the other hand, gas fuelled buses emit about 1.25 kg Co2/km (Tank-to-Wheel), which is eightfold the emissions of an electrical bus. The Well-to-Tank emissions further increase to about 1.32 kg Co2/km. The emission calculation is based on real gas consumption data from a Norwegian public transport utility. The results indicate that the combination of CHP plants and electrical buses provide a much higher efficiency while reducing Co2-emissions. (author)

  11. NAA of an iridium tracer to determine soot exposure of students commuting on Baltimore`s buses

    Energy Technology Data Exchange (ETDEWEB)

    Ondov, J.M.; Wu, C.C.; Lin, Zhibo; Kidwell, C.B. [Univ. of Maryland, College Park, MD (United States)

    1997-12-01

    Epidemiologic studies suggest that short-term increases in indices of particulate air pollution are associated with increased mortality and morbidity from respiratory and cardiovascular diseases. An important component of urban aerosol, diesel soot, is a known respiratory irritant and contains mutagenic and carcinogenic organic compounds. In the United States, motor vehicles are thought to be the largest single source of atmospheric soot and account for {approximately}36% of the annual anthropogenic emission of toxic polynuclear aromatic hydrocarbons (PAH). Much of the motor-vehicle-derived PAH originates from diesel-powered vehicles because their PAH emissions are up to 50-fold greater than those from gasoline engines. In Baltimore, city high school students take public buses to school and, often, must stand at bus stops while many diesel buses pass or stop before their own buses arrive. To estimate student exposures to soot emitted from public diesel buses (MTA) during commutes to city high schools, the Baltimore municipal fuel supply was tagged with an iridium tracer, and exposure was monitored during commutes with personal aerosol monitors as a part of the Baltimore Environmental Justice Project.

  12. Detection of maximum loadability limits and weak buses using Chaotic PSO considering security constraints

    International Nuclear Information System (INIS)

    Acharjee, P.; Mallick, S.; Thakur, S.S.; Ghoshal, S.P.

    2011-01-01

    Highlights: → The unique cost function is derived considering practical Security Constraints. → New innovative formulae of PSO parameters are developed for better performance. → The inclusion and implementation of chaos in PSO technique is original and unique. → Weak buses are identified where FACTS devices can be implemented. → The CPSO technique gives the best performance for all the IEEE standard test systems. - Abstract: In the current research chaotic search is used with the optimization technique for solving non-linear complicated power system problems because Chaos can overcome the local optima problem of optimization technique. Power system problem, more specifically voltage stability, is one of the practical examples of non-linear, complex, convex problems. Smart grid, restructured energy system and socio-economic development fetch various uncertain events in power systems and the level of uncertainty increases to a great extent day by day. In this context, analysis of voltage stability is essential. The efficient method to assess the voltage stability is maximum loadability limit (MLL). MLL problem is formulated as a maximization problem considering practical security constraints (SCs). Detection of weak buses is also important for the analysis of power system stability. Both MLL and weak buses are identified by PSO methods and FACTS devices can be applied to the detected weak buses for the improvement of stability. Three particle swarm optimization (PSO) techniques namely General PSO (GPSO), Adaptive PSO (APSO) and Chaotic PSO (CPSO) are presented for the comparative study with obtaining MLL and weak buses under different SCs. In APSO method, PSO-parameters are made adaptive with the problem and chaos is incorporated in CPSO method to obtain reliable convergence and better performances. All three methods are applied on standard IEEE 14 bus, 30 bus, 57 bus and 118 bus test systems to show their comparative computing effectiveness and

  13. Transition to a hydrogen fuel cell transit bus fleet for Canadian urban transit system

    International Nuclear Information System (INIS)

    Ducharme, P.

    2004-01-01

    'Full text:' The Canadian Transportation Fuel Cell Alliance (CTFCA), created by the Canadian Government as part of its 2000 Climate Change Action Plan, has commissioned MARCON-DDM's Hydrogen Intervention Team (HIT) to provide a roadmap for urban transit systems that wish to move to hydrogen fuel cell-powered bus fleets. HIT is currently in the process of gathering information from hydrogen technology providers, bus manufacturers, fuelling system providers and urban transit systems in Canada, the US and Europe. In September, HIT will be in a position to provide a preview of its report to the CTFCA, due for October 2004. The planned table of contents includes: TOMORROW'S FUEL CELL (FC) URBAN TRANSIT BUS - Powertrain, on-board fuel technologies - FC engine system manufacturers - Bus technical specifications, performances, operating characteristics - FC bus manufacturers TOMORROW'S FC TRANSIT PROPERTY - Added maintenance, facilities and fuelling infrastructure requirements - Supply chain implications - Environmental and safety issues - Alternative operational concepts PATHWAYS TO THE FUTURE - Choosing the future operational concept - 'Gap' assessment - how long from here to there? - Facilities and fleet adjustments, including fuelling infrastructure - Risk mitigation, code compliance measures TRANSITIONAL CONSIDERATIONS - Cost implications - Transition schedule (author)

  14. Thermodynamic analysis of the two-phase ejector air-conditioning system for buses

    International Nuclear Information System (INIS)

    Ünal, Şaban; Yilmaz, Tuncay

    2015-01-01

    Air-conditioning compressors of the buses are usually operated with the power taken from the engine of the buses. Therefore, an improvement in the air-conditioning system will reduce the fuel consumption of the buses. The improvement in the coefficient of performance (COP) of the air-conditioning system can be provided by using the two-phase ejector as an expansion valve in the air-conditioning system. In this study, the thermodynamic analysis of bus air-conditioning system enhanced with a two-phase ejector and two evaporators is performed. Thermodynamic analysis is made assuming that the mixing process in ejector occurs at constant cross-sectional area and constant pressure. The increase rate in the COP with respect to conventional system is analyzed in terms of the subcooling, condenser and evaporator temperatures. The analysis shows that COP improvement of the system by using the two phase ejector as an expansion device is 15% depending on design parameters of the existing bus air-conditioning system. - Highlights: • Thermodynamic analysis of the two-phase ejector refrigeration system. • Analysis of the COP increase rate of bus air-conditioning system. • Analysis of the entrainment ratio of the two-phase ejector refrigeration system

  15. Predicting self-pollution inside school buses using a CFD and multi-zone coupled model

    Science.gov (United States)

    Li, Fei; Lee, Eon S.; Liu, Junjie; Zhu, Yifang

    2015-04-01

    The in-cabin environment of a school bus is important for children's health. The pollutants from a bus's own exhaust contribute to children's overall exposure to air pollutants inside the school bus cabin. In this study, we adapted a coupled model originally developed for indoor environment to determine the relative contribution of the bus own exhaust to the in-cabin pollutant concentrations. The coupled model uses CFD (computational fluent dynamics) model to simulate outside concentration and CONTAM (a multi-zone model) for inside the school bus. The model was validated with experimental data in the literature. Using the validated model, we analyzed the effects of vehicle speed and tailpipe location on self-pollution inside the bus cabin. We confirmed that the pollution released from the tailpipe can penetrate into the bus cabin through gaps in the back emergency door. We found the pollution concentration inside school buses was the highest when buses were driven at a medium speed. In addition, locating the tailpipe on the side, behind the rear axle resulted in less self-pollution since there is less time for the suction effect to take place. The developed theoretical framework can be generalized to study other types of buses. These findings can be used in developing policy recommendations for reducing human exposure to air pollution inside buses.

  16. The Aerodynamics of Heavy Vehicles III : Trucks, Buses and Trains

    CERN Document Server

    Orellano, Alexander

    2016-01-01

    This volume contains papers presented at the International conference “The Aerodynamics of Heavy Vehicles III: Trucks, Buses and Trains” held in Potsdam, Germany, September 12-17, 2010 by Engineering Conferences International (ECI). Leading scientists and engineers from industry, universities and research laboratories, including truck and high-speed train manufacturers and operators were brought together to discuss computer simulation and experimental techniques to be applied for the design of more efficient trucks, buses and high-speed trains in the future.   This conference was the third in the series after Monterey-Pacific Groove in 2002 and Lake Tahoe in 2007.  The presentations address different aspects of train aerodynamics (cross wind effects, underbody flow, tunnel aerodynamics and aeroacoustics, experimental techniques), truck aerodynamics (drag reduction, flow control, experimental and computational techniques) as well as computational fluid dynamics and bluff body, wake and jet flows.

  17. Optimization of transit bus fleet's life cycle assessment impacts with alternative fuel options

    International Nuclear Information System (INIS)

    Ercan, Tolga; Zhao, Yang; Tatari, Omer; Pazour, Jennifer A.

    2015-01-01

    Public transportation is one of the most promising transportation modes to reduce the environmental emissions of the transportation sector in the U.S. In order to mitigate the environmental impacts brought by the transit bus system, new energy buses are introduced into the vehicle market. The goal of this study is to find an optimal bus fleet combination for different driving conditions to minimize life cycle cost, greenhouse gas emissions, and conventional air pollutant emission impacts. For this purpose, a Multi-Objective Linear Programming approach is used to select the optimum bus fleet combinations. Given different weight scenarios, this method could effectively provide solutions for decision makers with various budget constraints or emission reduction requirements. The results indicate that in heavily congested driving cycles such as the Manhattan area, the battery electric bus is the dominant vehicle type, while the hybrid bus has more balanced performances in most scenarios because of its lower initial investment comparing to battery electric buses. Petroleum powered buses have seldom been selected by the model. The trade-off analysis shows that the overall greenhouse gas impact performance is sensitive to the life cycle cost after certain points, which could provide valuable information for the bus fleet combination planning. - Highlights: • Hybrid-Life Cycle Assessment analysis approach for transit bus operations. • Optimizing the economic and sustainability impacts of transit bus fleet operation. • CO 2 emissions and other air pollutants related health and environmental damage cost. • Trade-offs between CO 2 emissions and cost of transit bus fleet operation.

  18. Location Planning for Dynamic Wireless Charging Systems for Electric Airport Passenger Buses

    Directory of Open Access Journals (Sweden)

    Stefan Helber

    2018-01-01

    Full Text Available The majority of the ground vehicles operating on the airside parts of commercial airports are currently powered by diesel engines. These include vehicles such as apron buses, fuel trucks, and aircraft tractors. Hence, these vehicles contribute to the overall CO 2 emissions of the aviation transport system and thus negatively influence its environmental footprint. To reduce this damaging environmental impact, these vehicles could potentially be electrified with on-board batteries as their energy sources. However, the conductive charging of such vehicles via stationary cable connections is rather time-consuming. A dynamic wireless charging system to supply public transportation passenger buses with electric energy while in motion has recently been installed on the Korea Advanced Institute of Science and Technology (KAIST campus and in the Korean city of Gumi. In this paper, we study configuration problems related to the use of this technology to make airport operations more environmentally sustainable. We concentrate on the power supply for apron buses and analyze the location planning problems related to the distribution of the required power supply and the wireless charging units in the apron road system. To this end, we develop a formal optimization model and discuss the first numerical results.

  19. Bus transit operational efficiency resulting from passenger boardings at park-and-ride facilities.

    Science.gov (United States)

    2016-08-01

    In order to save time and money by not driving to an ultimate destination, some urban commuters drive themselves a few miles to specially designated parking lots built for transit customers and located where trains or buses stop. The focus of this pa...

  20. Final Report: Mass Production Cost Estimation of Direct H2 PEM Fuel Cell Systems for Transportation Applications (2012-2016)

    Energy Technology Data Exchange (ETDEWEB)

    James, Brian David [Strategic Analysis Inc., Arlington, VA (United States); Huya-Kouadio, Jennie Moton [Strategic Analysis Inc., Arlington, VA (United States); Houchins, Cassidy [Strategic Analysis Inc., Arlington, VA (United States); DeSantis, Daniel Allen [Strategic Analysis Inc., Arlington, VA (United States)

    2016-09-01

    This report summarizes project activities for Strategic Analysis, Inc. (SA) Contract Number DE-EE0005236 to the U.S. Department of Energy titled “Transportation Fuel Cell System Cost Assessment”. The project defined and projected the mass production costs of direct hydrogen Proton Exchange Membrane fuel cell power systems for light-duty vehicles (automobiles) and 40-foot transit buses. In each year of the five-year contract, the fuel cell power system designs and cost projections were updated to reflect technology advances. System schematics, design assumptions, manufacturing assumptions, and cost results are presented.

  1. Buses retrofitting with diesel particle filters: Real-world fuel economy and roadworthiness test considerations.

    Science.gov (United States)

    Fleischman, Rafael; Amiel, Ran; Czerwinski, Jan; Mayer, Andreas; Tartakovsky, Leonid

    2018-05-01

    Retrofitting older vehicles with diesel particulate filter (DPF) is a cost-effective measure to quickly and efficiently reduce particulate matter emissions. This study experimentally analyzes real-world performance of buses retrofitted with CRT DPFs. 18 in-use Euro III technology urban and intercity buses were investigated for a period of 12months. The influence of the DPF and of the vehicle natural aging on buses fuel economy are analyzed and discussed. While the effect of natural deterioration is about 1.2%-1.3%, DPF contribution to fuel economy penalty is found to be 0.6% to 1.8%, depending on the bus type. DPF filtration efficiency is analyzed throughout the study and found to be in average 96% in the size range of 23-560nm. Four different load and non-load engine operating modes are investigated on their appropriateness for roadworthiness tests. High idle is found to be the most suitable regime for PN diagnostics considering particle number filtration efficiency. Copyright © 2017. Published by Elsevier B.V.

  2. Developing a Natural Gas-Powered Bus Rapid Transit Service: A Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, G.

    2015-11-03

    The Roaring Fork Transit Authority (RFTA) and its VelociRFTA Bus Rapid Transit (BRT) program are unique in many ways. For example, VelociRFTA was the first rural BRT system in the United States and the operational environment of the VelociRFTA BRT is one of the most severe in the country, with extreme winter temperatures and altitudes close to 8,000 feet. RFTA viewed high altitude operation as the most challenging characteristic when it began considering the use of natural gas. RFTA is the second-largest public transit system in Colorado behind Denver's Regional Transportation District (RTD), and it is one of the largest rural public transit systems in the country. In 2013, RFTA accepted delivery of 22 new compressed natural gas (CNG) buses that went into service after completion of maintenance and refueling facilities earlier that year. This paper examines the lessons learned from RFTA's experience of investigating--and ultimately choosing--CNG for their new BRT program and focuses on the unique environment of RFTA's BRT application; the decision process to include CNG fueling in the project; unforeseen difficulties encountered in the operation of CNG buses; public perception; cost comparison to competing fuels; and considerations for indoor fueling facilities and project funding.

  3. Developing a Natural Gas-Powered Bus Rapid Transit Service. A Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, George [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-11-01

    The Roaring Fork Transit Authority (RFTA) and its VelociRFTA Bus Rapid Transit (BRT) program are unique in many ways. For example, VelociRFTA was the first rural BRT system in the United States and the operational environment of the VelociRFTA BRT is one of the most severe in the country, with extreme winter temperatures and altitudes close to 8,000 feet. RFTA viewed high altitude operation as the most challenging characteristic when it began considering the use of natural gas. RFTA is the second-largest public transit system in Colorado behind Denver's Regional Transportation District (RTD), and it is one of the largest rural public transit systems in the country. In 2013, RFTA accepted delivery of 22 new compressed natural gas (CNG) buses that went into service after completion of maintenance and refueling facilities earlier that year. This paper examines the lessons learned from RFTA's experience of investigating--and ultimately choosing--CNG for their new BRT program and focuses on the unique environment of RFTA's BRT application; the decision process to include CNG fueling in the project; unforeseen difficulties encountered in the operation of CNG buses; public perception; cost comparison to competing fuels; and considerations for indoor fueling facilities and project funding.

  4. School buses, air pollution and children's health: follow-up report

    Energy Technology Data Exchange (ETDEWEB)

    Perrotta, K. [Clean Air Partnership, Toronto, ON (Canada)], email: Kperrotta@cleanairpartnership.org

    2010-10-15

    This document is designed to be a follow-up report to the Ontario Public Health Association (OPHA) school bus report published in 2005, and was produced through a collaboration between the Clean Air Partnership and the OPHA. The level of awareness of school bus emissions are evaluated in this report. The document also provides a review of projects handled by the federal government, programs developed by governments of other provinces and the policies followed by school boards in other provinces, to mitigate emissions and exposures related to school buses. Several recommendations were made, including the replacement of older school buses, adapt the routes considering the emissions generated and promote the use of biodiesel to reduce emissions of air pollutants and greenhouse gases. 36 refs, 8 tabs.

  5. Ultrafine particle emissions by in-use diesel buses of various generations at low-load regimes

    Science.gov (United States)

    Tartakovsky, L.; Baibikov, V.; Comte, P.; Czerwinski, J.; Mayer, A.; Veinblat, M.; Zimmerli, Y.

    2015-04-01

    Ultrafine particles (UFP) are major contributors to air pollution due to their easy gas-like penetration into the human organism, causing adverse health effects. This study analyzes UFP emissions by buses of different technologies (from Euro II till Euro V EEV - Enhanced Environmentally-friendly Vehicle) at low-load regimes. Additionally, the emission-reduction potential of retrofitting with a diesel particle filter (DPF) is demonstrated. A comparison of the measured, engine-out, particle number concentrations (PNC) for buses of different technological generations shows that no substantial reduction of engine-out emissions at low-load operating modes is observed for newer bus generations. Retrofitting the in-use urban and interurban buses of Euro II till Euro IV technologies by the VERT-certified DPF confirmed its high efficiency in reduction of UFP emissions. Particle-count filtration efficiency values of the retrofit DPF were found to be extremely high - greater than 99.8%, similar to that of the OEM filter in the Euro V bus.

  6. From prototype to product. The development of low emission natural gas- and biogas buses

    Energy Technology Data Exchange (ETDEWEB)

    Ekelund, M. [Strateco Development AB, Haninge (Sweden)

    1998-01-01

    The objective of this report is to show the development of natural gas and bio gas buses and trucks since the termination of the `Co-Nordic GasBus Project`, to which KFB was a major contributor and one of the initiators. Sweden have some 325 heavy duty methane vehicles of which almost 100 are bio gas operated. Scania and Volvo have produced, or have orders for, 500 gas buses to 6 different countries since 1990. The Project objectives were obtained and the significantly reduced emission levels aimed for, were shown. The international bus manufacturing industry followed, and have since shown the same low levels of emissions from gas bus engines. Sweden has taken the lead in the use of bio gas, by operating nearly 100 buses and trucks. Bio gas is still an underestimated fuel when it comes to supply, as it can provide fuel for 50% of the domestic use of diesel oil. Future development need to include control systems for more stable emissions, lower weight cylinders, less costly compressors, cleaning equipment and storage cylinders as well as more fuel efficient engines that can reduce mainly the discharge of CO2, NOx and CH4 further. Societal costs, regardless of who pays, for methane operated buses is still somewhat higher compared with best use of diesel + CRT technology. As commercialization develops, it is expected that the price of the vehicle will be reduced and emissions improved. It is therefore expected that the stake holders costs will be lower then that of diesel technology in the future

  7. Luxurious Buses As Means Of Night Journey In Nigeria: Challenges ...

    African Journals Online (AJOL)

    transfer to discourage robbery cases on our roads. Passengers should also keep their traveling plans secret as much as possible as a way of fostering safety. Keywords: night journey, armed robbers, luxurious buses and police escorts. Ethiopian Journal of Environmental Studies and Management Vol. 1 (3) 2008: pp. 52-62.

  8. Fuel cells for vehicle applications in cars - bringing the future closer

    Science.gov (United States)

    Panik, Ferdinand

    Among all alternative drive systems, the fuel cell electric propulsion system has the highest potential to compete with the internal combustion engine. For this reason, Daimler-Benz AG has entered into a co-operative alliance with Ballard Power Systems, with the objectives of bringing fuel cell vehicles to the market. Apart from the fuel cell itself, fuel cell vehicles require comprehensive system technology to provide fuel and air supply, cooling, energy management, electric and electronic functions. The system technology determines to a large extent the cost, weight, efficiency, performance and overall customer benefit of fuel cell vehicles. Hence, Daimler-Benz and Ballard are pooling their expertise in fuel cell system technology in a joint company, with the aim of bringing their fuel cell vehicular systems to the stage of maturity required for market entry as early as possible. Hydrogen-fuelled zero-emission fuel cell transit `buses' will be the first market segment addressed, with an emphasis on the North American and European markets. The first buses are already scheduled for delivery to customers in late 1997. Since a liquid fuel like methanol is easier to handle in passenger cars, fuel reforming technologies are developed and will shortly be demonstrated in a prototype, as well. The presentation will cover concepts of fuel cell vehicles with an emphasis on system technology, the related testing procedures and results as well as an outline of market entry strategies.

  9. Development and Evaluation of an Economic-Driving Assistance Program for Transit Vehicles

    OpenAIRE

    Baoxin Han; Wanjing Ma; Hanzhou Xie

    2012-01-01

    This paper focuses on development and evaluation of an economic-driving assistance program for transit vehicles (EDTV) which can minimize energy consumption, air pollution emission of buses, and improve the level of service of transit system as well. Taking advantage of the latest advances in information and communication technologies, the EDTV system can provide bus drivers with optimal recommended bus holding times at near-side bus stops and dynamic bus speed to adapt to the real-time traff...

  10. Preliminary study on field buses for the control system of the high voltage of the ATLAS hadronic calorimeter

    International Nuclear Information System (INIS)

    Drevet, F.; Chadelas, R.; Montarou, G.

    1996-01-01

    We present here after a preliminary study on field buses for the control system of the high voltage of the photomultipliers of the TILECAL calorimeter. After some generalities, different commercial buses are reviewed (CAN, ARCET, WorldFIP, Profibus and LonWorks). The Profibus and LonWorks solution are more extensively studies as a possible solution for the high voltage system of the TILE hadronic calorimeter. (authors)

  11. Communication Buses and Protocols for Sensor Networks

    Directory of Open Access Journals (Sweden)

    Andrew Mason

    2002-07-01

    Full Text Available This paper overviews existing digital communication buses which are commonly used in sensor networks, discusses sensor network architectures, and introduces a new sensor bus for low power microsystem applications. The new intra-module multi-element microsystem (IM2 bus is nine-line interface with 8b serial data which implements several advanced features such as power management and plug-n-play while maintaining minimum hardware overhead at the sensor node. Finally, some issues in wireless sensor networking are discussed. The coverage of these issues provides a guideline for choosing the appropriate bus for different sensor network applications.

  12. Aerosol particles generated by diesel-powered school buses at urban schools as a source of children's exposure.

    Science.gov (United States)

    Hochstetler, Heather A; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H; Grinshpun, Sergey A

    2011-03-01

    Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 µg m -3 . The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors).

  13. Clean air program : design guidelines for bus transit systems using electric and hybrid electric propulsion as an alternative fuel

    Science.gov (United States)

    2003-03-01

    The use of alternative fuels to power transit buses is steadily increasing. Several fuels, including : Compressed Natural Gas (CNG), Liquefied Natural Gas (LNG), Liquefied Petroleum Gas (LPG), and : Methanol/Ethanol, are already being used. At presen...

  14. Quantification of self pollution from two diesel school buses using three independent methods

    Science.gov (United States)

    Sally Liu, L.-J.; Phuleria, Harish C.; Webber, Whitney; Davey, Mark; Lawson, Douglas R.; Ireson, Robert G.; Zielinska, Barbara; Ondov, John M.; Weaver, Christopher S.; Lapin, Charles A.; Easter, Michael; Hesterberg, Thomas W.; Larson, Timothy

    2010-09-01

    We monitored two Seattle school buses to quantify the buses' self pollution using the dual tracers (DT), lead vehicle (LV), and chemical mass balance (CMB) methods. Each bus drove along a residential route simulating stops, with windows closed or open. Particulate matter (PM) and its constituents were monitored in the bus and from a LV. We collected source samples from the tailpipe and crankcase emissions using an on-board dilution tunnel. Concentrations of PM 1, ultrafine particle counts, elemental and organic carbon (EC/OC) were higher on the bus than the LV. The DT method estimated that the tailpipe and the crankcase emissions contributed 1.1 and 6.8 μg m -3 of PM 2.5 inside the bus, respectively, with significantly higher crankcase self pollution (SP) when windows were closed. Approximately two-thirds of in-cabin PM 2.5 originated from background sources. Using the LV approach, SP estimates from the EC and the active personal DataRAM (pDR) measurements correlated well with the DT estimates for tailpipe and crankcase emissions, respectively, although both measurements need further calibration for accurate quantification. CMB results overestimated SP from the DT method but confirmed crankcase emissions as the major SP source. We confirmed buses' SP using three independent methods and quantified crankcase emissions as the dominant contributor.

  15. Battery Peak Power Shaving Strategy to Prolong Battery Life for Electric Buses

    NARCIS (Netherlands)

    Pham, T.H.; Rosea, B.; Wilkins, S.

    2016-01-01

    This paper presents a battery peak power shaving strategy for battery electric buses. The developed strategy restricts the battery charge/discharge power when the propulsion power demand is high to avoid high deterioration of the battery capacity during operation. Without reducing the propulsion

  16. A Feeder-Bus Dispatch Planning Model for Emergency Evacuation in Urban Rail Transit Corridors

    Science.gov (United States)

    Wang, Yun; Yan, Xuedong; Zhou, Yu; Zhang, Wenyi

    2016-01-01

    The mobility of modern metropolises strongly relies on urban rail transit (URT) systems, and such a heavy dependence causes that even minor service interruptions would make the URT systems unsustainable. This study aims at optimally dispatching the ground feeder-bus to coordinate with the urban rails’ operation for eliminating the effect of unexpected service interruptions in URT corridors. A feeder-bus dispatch planning model was proposed for the collaborative optimization of URT and feeder-bus cooperation under emergency situations and minimizing the total evacuation cost of the feeder-buses. To solve the model, a concept of dummy feeder-bus system is proposed to transform the non-linear model into traditional linear programming (ILP) model, i.e., traditional transportation problem. The case study of Line #2 of Nanjing URT in China was adopted to illustrate the model application and sensitivity analyses of the key variables. The modeling results show that as the evacuation time window increases, the total evacuation cost as well as the number of dispatched feeder-buses decrease, and the dispatched feeder-buses need operate for more times along the feeder-bus line. The number of dispatched feeder-buses does not show an obvious change with the increase of parking spot capacity and time window, indicating that simply increasing the parking spot capacity would cause huge waste for the emergent bus utilization. When the unbalanced evacuation demand exists between stations, the more feeder-buses are needed. The method of this study will contribute to improving transportation emergency management and resource allocation for URT systems. PMID:27676179

  17. Diesel vs. compressed natural gas for school buses: a cost-effectiveness evaluation of alternative fuels

    International Nuclear Information System (INIS)

    Cohen, J.T.

    2005-01-01

    Reducing emissions from school buses is a priority for both state and federal regulators. Two popular alternative technologies to conventional diesel (CD) are emission controlled diesel (ECD), defined here to be diesel buses equipped with continuously regenerating particle filters, and engines fueled by compressed natural gas (CNG). This paper uses a previously published model to quantify the impact of particulate matter (PM), oxides of nitrogen (NO x ), and sulfur dioxide (SO 2 ) emissions on population exposure to ozone and to primary and secondary PM, and to quantify the resulting health damages, expressed in terms of lost quality adjusted life years (QALYs). Resource costs include damages from greenhouse gas-induced climate change, vehicle procurement, infrastructure development, and operations. I find that ECD and CNG produce very similar reductions in health damages compared to CD, although CNG has a modest edge because it may have lower NO x emissions. However, ECD is far more cost effective ($400,000-900,000 cost per QALY saved) than CNG (around $4 million per QALY saved). The results are uncertain because the model used makes a series of simplifying assumptions and because emissions data and cost data for school buses are very limited

  18. Modeling of passengers' safety perception for buses on mountainous roads.

    Science.gov (United States)

    Khoo, Hooi Ling; Ahmed, Muaid

    2018-04-01

    This study had developed a passenger safety perception model specifically for buses taking into consideration the various factors, namely driver characteristics, environmental conditions, and bus characteristics using Bayesian Network. The behaviour of bus driver is observed through the bus motion profile, measured in longitudinal, lateral, and vertical accelerations. The road geometry is recorded using GPS and is computed with the aid of the Google map while the perceived bus safety is rated by the passengers in the bus in real time. A total of 13 variables were derived and used in the model development. The developed Bayesian Network model shows that the type of bus and the experience of the driver on the investigated route could have an influence on passenger's perception of their safety on buses. Road geometry is an indirect influencing factor through the driver's behavior. The findings of this model are useful for the authorities to structure an effective strategy to improve the level of perceived bus safety. A high level of bus safety will definitely boost passenger usage confidence which will subsequently increase ridership. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. School buses, air pollution and children's health : improving children's health and local air quality by reducing school bus emissions

    Energy Technology Data Exchange (ETDEWEB)

    Perrotta, K. [Ontario Public Health Association, Toronto, ON (Canada)

    2005-11-01

    The exhaust gases from school buses was examined and recommendations were presented for the establishment of a healthy school bus program in Ontario that is directed at improving children's health and local air quality. The Ontario Public Health Association is concerned with school bus emissions because they are heavy-duty vehicles that emit large quantities of diesel-related air pollutants such as fine particulate matter, nitrogen oxides and diesel particulates. In addition, school buses can be self-polluting vehicles that expose children on-board to high levels of fine particulates and diesel particulate matter. Both these pollutants have been associated with a range of acute and chronic health problems such as asthma, respiratory infections, allergies, and school absences. With nearly 800,000 Ontario children being transported on school buses annually, these exposures can represent a serious public health concern, as childhood exposures can also influence the health of exposed individuals later in life. Exposure studies have found that tailpipe and engine emissions contribute greatly to concentrations of air pollutants on-board school buses. The studies also showed that on-board concentrations were also influenced by local air quality in the communities studied, traffic density, wind direction, the configuration of windows, idling and queuing patterns. It was recommended that the use of ultra-low sulphur diesel fuel along with the installation of diesel particulate filters and closed crankcase filters can reduce the concentrations of air pollutants on-board school buses to almost ambient air levels, even under idling conditions. This report recommended the replacement of pre-1994 school buses, the retrofitting of 1994-2003 school buses with filters, and maintaining proper maintenance, idling and vehicle operation practices. refs., tabs., figs.

  20. 76 FR 77888 - Student Transportation of America, Inc.-Control-Dairyland Buses, Inc.

    Science.gov (United States)

    2011-12-14

    ... Wisconsin law, also holds a FMCSA license (MC-170747) and is owned by Coach USA, Inc., a Delaware..., 2011, from their current owner, Coach USA, Inc., into an independent voting trust established under 49... Transportation of America, Inc.--Control--Dairyland Buses, Inc. AGENCY: Surface Transportation Board. ACTION...

  1. Multi-criteria analysis of alternative-fuel buses for public transportation

    International Nuclear Information System (INIS)

    Tzeng, G.-H.; Lin, C.-W.; Opricovic, Serafim

    2005-01-01

    The technological development of buses with new alternative fuels is considered in this paper. Several types of fuels are considered as alternative-fuel modes, i.e., electricity, fuel cell (hydrogen), and methanol. Electric vehicles may be considered the alternative-fuel vehicles with the lowest air pollution. Hybrid electric vehicles provide an alternate mode, at least for the period of improving the technology of electric vehicles. A hybrid electric vehicle is defined as a vehicle with the conventional internal combustion engine and an electric motor as its major sources of power. Experts from different decision-making groups performed the multiple attribute evaluation of alternative vehicles. AHP is applied to determine the relative weights of evaluation criteria. TOPSIS and VIKOR are compared and applied to determine the best compromise alternative fuel mode. The result shows that the hybrid electric bus is the most suitable substitute bus for Taiwan urban areas in the short and median term. But, if the cruising distance of the electric bus extends to an acceptable range, the pure electric bus could be the best alternative

  2. Combustion Chemistry of Biodiesel for the Use in Urban Transport Buses: Experiment and Modeling

    Science.gov (United States)

    Omidvarborna, Hamid

    Biofuels, such as biodiesel, offer benefits as a possible alternative to conventional fuels due to their fuel source sustainability and their reduced environmental impact. Before they can be used, it is essential to understand their combustion chemistry and emission characterizations due to a number of issues associated with them (e.g., high emission of nitrogen oxides (NOx), lower heating value than diesel, etc.). During this study, emission characterizations of different biodiesel blends (B0, B20, B50, and B100) were measured on three different feedstocks (soybean methyl ester (SME), tallow oil (TO), and waste cooking oil (WCO)) with various characteristics, while an ultra-low sulfur diesel (ULSD) was used as base fuel at low-temperature combustion (LTC). A laboratory combustion chamber was used to analyze soot formation, NOx emissions, while real engine emissions were measured for further investigation on PM and NOx emissions. For further study, carbon emissions (CO, CO 2, and CH4) were also measured to understand their relations with feedstocks' type. The emissions were correlated with fuel's characteristics, especially unsaturation degree (number of double bonds in methyl esters) and chain length (oxygen-to-carbon ratio). The experimental results obtained from laboratory experiments were confirmed by field experiments (real engines) collected from Toledo area regional transit authority (TARTA) buses. Combustion analysis results showed that the neat biodiesel fuels had longer ignition delays and lower ignition temperatures compared to ULSD at the tested condition. The results showed that biodiesel containing more unsaturated fatty acids emitted higher levels of NOx compared to biodiesel with more saturated fatty acids. A paired t-test on fuels showed that neat biodiesel fuels had significant reduction in the formation of NOx compared with ULSD. In another part of this study, biodiesel fuel with a high degree of unsaturation and high portion of long chains of

  3. Demonstration of 3 buses fuelled with ethanol with ignition improver in the Netherlands

    NARCIS (Netherlands)

    Verweij, J.; Weide, J. van der; Nie, L.H. de; Bruin, A. de

    1996-01-01

    This three year demonstration programme was initiated by OBL, a subsidiary of two Dutch sugar companies, and GADO, a public transport company. The programme was financially supported by a regional governmental organisation (ISP). In this programme, three bio-ethanol fuelled buses accumulated more

  4. Hydrogen fuel cells for cars and buses

    NARCIS (Netherlands)

    Janssen, L.J.J.

    2007-01-01

    The use of hydrogen fuel cells for cars is strongly promoted by the governments of many countries and by international organizations like the European Community. The electrochem. behavior of the most promising fuel cell (polymer electrolyte membrane fuel cell, PEMFC) is critically discussed, based

  5. Challenges and Experiences with Electric Propulsion Transit Buses in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Gifford, M.

    2003-11-01

    Document provides background for transit agencies and fleets that are considering electric propulsion technologies. It tells them what to expect and plan for when implementing vehicles with electric propulsion systems.

  6. Emissions of toxic pollutants from compressed natural gas and low sulfur diesel-fueled heavy-duty transit buses tested over multiple driving cycles.

    Science.gov (United States)

    Kado, Norman Y; Okamoto, Robert A; Kuzmicky, Paul A; Kobayashi, Reiko; Ayala, Alberto; Gebel, Michael E; Rieger, Paul L; Maddox, Christine; Zafonte, Leo

    2005-10-01

    The number of heavy-duty vehicles using alternative fuels such as compressed natural gas (CNG) and new low-sulfur diesel fuel formulations and equipped with after-treatment devices are projected to increase. However, few peer-reviewed studies have characterized the emissions of particulate matter (PM) and other toxic compounds from these vehicles. In this study, chemical and biological analyses were used to characterize the identifiable toxic air pollutants emitted from both CNG and low-sulfur-diesel-fueled heavy-duty transit buses tested on a chassis dynamometer over three transient driving cycles and a steady-state cruise condition. The CNG bus had no after-treatment, and the diesel bus was tested first equipped with an oxidation catalyst (OC) and then with a catalyzed diesel particulate filter (DPF). Emissions were analyzed for PM, volatile organic compounds (VOCs; determined on-site), polycyclic aromatic hydrocarbons (PAHs), and mutagenic activity. The 2000 model year CNG-fueled vehicle had the highest emissions of 1,3-butadiene, benzene, and carbonyls (e.g., formaldehyde) of the three vehicle configurations tested in this study. The 1998 model year diesel bus equipped with an OC and fueled with low-sulfur diesel had the highest emission rates of PM and PAHs. The highest specific mutagenic activities (revertants/microg PM, or potency) and the highest mutagen emission rates (revertants/mi) were from the CNG bus in strain TA98 tested over the New York Bus (NYB) driving cycle. The 1998 model year diesel bus with DPF had the lowest VOCs, PAH, and mutagenic activity emission. In general, the NYB driving cycle had the highest emission rates (g/mi), and the Urban Dynamometer Driving Schedule (UDDS) had the lowest emission rates for all toxics tested over the three transient test cycles investigated. Also, transient emissions were, in general, higher than steady-state emissions. The emissions of toxic compounds from an in-use CNG transit bus (without an oxidation

  7. Aerosol particles generated by diesel-powered school buses at urban schools as a source of children’s exposure

    Science.gov (United States)

    Hochstetler, Heather A.; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H.; Grinshpun, Sergey A.

    2015-01-01

    Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 µg m−3. The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors). PMID:25904818

  8. New buses and links for data acquisition

    International Nuclear Information System (INIS)

    Mueller, H.; Bogaerts, A.; McLaren, R.; Parkman, C.; Linnhoefer, D.

    1992-01-01

    Bus standards for data acquisition have been vital for the construction and operation of medium and large HEP experiments. The recent industry bus standardisation effort will soon release the next generation of high performance buses and links for scalable systems. Prototype components, VLSI chips and board-level systems are already announced. Layers of the new bus specifications cover wide areas of applications and provide possibilities to define specific bus profiles by interest groups. New, innovative solutions which are needed for high rate experiments are becoming visible. These will provide novel architectural possibilities, very high bandwidth, fast silicon, industry support and new metric mechanical standards. Interconnected via standard bridges, different bus standards can be used to cover the varying requirements from the front ends to the computers. (orig.)

  9. Real-world emissions and fuel consumption of diesel buses and trucks in Macao: From on-road measurement to policy implications

    Science.gov (United States)

    Wu, Xiaomeng; Zhang, Shaojun; Wu, Ye; Li, Zhenhua; Zhou, Yu; Fu, Lixin; Hao, Jiming

    2015-11-01

    A total of 13 diesel buses and 12 diesel trucks in Macao were tested using portable emission measurement systems (PEMS) including a SEMTECH-DS for gaseous emissions and a SEMTECH-PPMD for PM2.5. The average emission rates of gaseous pollutants and CO2 are developed with the operating mode defined by the instantaneous vehicle specific power (VSP) and vehicle speed. Both distance-based and fuel mass-based emission factors for gaseous pollutants (e.g., CO, THC and NOX) are further estimated under typical driving conditions. The average distance-based NOX emission of heavy-duty buses (HDBs) is higher than 13 g km-1. Considering the unfavorable conditions for selective reductions catalyst (SCR) systems, such as low-speed driving conditions, more effective technology options (e.g., dedicated natural gas buses and electric buses) should be considered by policy makers in Macao. We identified strong effects of the vehicle size, engine displacement and driving conditions on real-world CO2 emission factors and fuel consumption for diesel vehicles. Therefore, detailed profiles regarding vehicle specifications can reduce the uncertainty in their fleet-average on-road fuel consumption. In addition, strong correlations between relative emission factors and driving conditions indicated by the average speed of generated micro-trips are identified based on a micro-trip method. For example, distance-based emission factors of HDBs will increase by 39% for CO, 29% for THC, 43% for NOX and 26% for CO2 when the average speed decreases from 30 km h-1 to 20 km h-1. The mitigation of on-road emissions from diesel buses and trucks by improving traffic conditions through effective traffic and economic management measures is therefore required. This study demonstrates the important role of PEMS in understanding vehicle emissions and mitigation strategies from science to policy perspectives.

  10. Transportation of Wheelchair Seated Students in School Buses: A Review of State Policy

    Science.gov (United States)

    Moore, Britta; Fuhrman, Susan; Karg, Patricia

    2010-01-01

    This study quantitatively reviews publicly available state policies as they relate to the transportation of wheelchair-seated students in school buses. Inclusion of best practices in specially equipped school bus and driver training policies was assessed. Key points of interest within state policies were identified based on site visits, common…

  11. Alternative Fuels for Washington's School Buses: A Report to the Washington State Legislature.

    Science.gov (United States)

    Lyons, John Kim; McCoy, Gilbert A.

    This document presents findings of a study that evaluated the use of both propane and compressed natural gas as alternative fuels for Washington State school buses. It discusses air quality improvement actions by state- and federal-level regulators and summarizes vehicle design, development, and commercialization activities by all major engine,…

  12. The Fuel Economy of Hybrid Buses: The Role of Ancillaries in Real Urban Driving

    Directory of Open Access Journals (Sweden)

    Francesco Bottiglione

    2014-07-01

    Full Text Available In the present context of the global economic crisis and environmental emergency, transport science is asked to find innovative solutions to turn traditional vehicles into fuel-saving and eco-friendly devices. In the last few years, hybrid vehicles have been shown to have potential benefits in this sense. In this paper, the fuel economy of series hybrid-electric and hybrid-mechanical buses is simulated in two real driving situations: cold and hot weather driving in the city of Taranto, in Southern Italy. The numerical analysis is carried out by an inverse dynamic approach, where the bus speed is given as a velocity pattern measured in the field tests performed on one of the city bus routes. The city of Taranto drive schedule is simulated in a typical tempered climate condition and with a hot temperature, when the air conditioning system must be switched on for passenger comfort. The fuel consumptions of hybrid-electric and hybrid-mechanical buses are compared to each other and with a traditional bus powered by a diesel engine. It is shown that the series hybrid-electric vehicle outperforms both the traditional and the mechanical hybrid vehicles in the cold weather driving simulation, reducing the fuel consumption by about 35% with respect to the traditional diesel bus. However, it is also shown that the performance of the hybrid-electric bus gets dramatically worse when the air-cooling system is continuously turned on. In this situation, the fuel consumption of the three different technologies for city buses under investigation is comparable.

  13. Surgical management for upper urinary tract transitional cell carcinoma.

    Science.gov (United States)

    Rai, Bhavan Prasad; Shelley, Mike; Coles, Bernadette; Biyani, Chandra S; El-Mokadem, Ismail; Nabi, Ghulam

    2011-04-13

    Upper tract transitional cell carcinomas (TCC) are uncommon and aggressive tumours. There are a number of surgical approaches to manage this condition including open radical nephroureterectomy and laparoscopic procedures. To determine the best surgical management option for upper tract transitional cell carcinoma. A sensitive search strategy was developed to identify relevant studies for inclusion in this review. The following databases were searched for randomised trials evaluating surgical approaches to the management of upper tract TCC: Medline EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL, British Nursing Index, AMED, LILACS, Web of Science®, Scopus, Biosis, TRIP, Biomed Central, Dissertation Abstracts, and ISI Proceedings. The following criteria that were considered for this review.Types of studies - All randomised or quasi-randomised controlled trials comparing the various surgical methods and approaches for the management of localised upper tract transitional cell carcinoma. Types of participants - All adult patients with localised transitional cell carcinoma. Localised disease was defined as limited to the kidney or ureter with no gross regional lymph nodal enlargement on imaging. Types of interventions - Any surgical method or approach for managing localised upper tract transitional cell carcinoma. Types of outcome measures - Overall and cancer-specific survival were primary outcomes. Surgery-related morbidity. Quality of life and health economics outcomes were secondary outcomes. Two review authors examined the search results independently to identify trials for inclusion. We identified one randomised controlled trial that met our inclusion criteria. The trial showed that the laparoscopic approach had superior peri-operative outcomes compared to open approach. Laparoscopic was superior and statistically significant for blood loss (104 mL (millilitres) versus 430 mL, P management of upper tract transitional cell carcinoma

  14. Visualizing cell state transition using Raman spectroscopy.

    Directory of Open Access Journals (Sweden)

    Taro Ichimura

    Full Text Available System level understanding of the cell requires detailed description of the cell state, which is often characterized by the expression levels of proteins. However, understanding the cell state requires comprehensive information of the cell, which is usually obtained from a large number of cells and their disruption. In this study, we used Raman spectroscopy, which can report changes in the cell state without introducing any label, as a non-invasive method with single cell capability. Significant differences in Raman spectra were observed at the levels of both the cytosol and nucleus in different cell-lines from mouse, indicating that Raman spectra reflect differences in the cell state. Difference in cell state was observed before and after the induction of differentiation in neuroblastoma and adipocytes, showing that Raman spectra can detect subtle changes in the cell state. Cell state transitions during embryonic stem cell (ESC differentiation were visualized when Raman spectroscopy was coupled with principal component analysis (PCA, which showed gradual transition in the cell states during differentiation. Detailed analysis showed that the diversity between cells are large in undifferentiated ESC and in mesenchymal stem cells compared with terminally differentiated cells, implying that the cell state in stem cells stochastically fluctuates during the self-renewal process. The present study strongly indicates that Raman spectral morphology, in combination with PCA, can be used to establish cells' fingerprints, which can be useful for distinguishing and identifying different cellular states.

  15. Transitional basal cells at the squamous-columnar junction generate Barrett’s oesophagus

    Science.gov (United States)

    Jiang, Ming; Li, Haiyan; Zhang, Yongchun; Yang, Ying; Lu, Rong; Liu, Kuancan; Lin, Sijie; Lan, Xiaopeng; Wang, Haikun; Wu, Han; Zhu, Jian; Zhou, Zhongren; Xu, Jianming; Lee, Dong-Kee; Zhang, Lanjing; Lee, Yuan-Cho; Yuan, Jingsong; Abrams, Julian A.; Wang, Timothy G.; Sepulveda, Antonia R.; Wu, Qi; Chen, Huaiyong; Sun, Xin; She, Junjun; Chen, Xiaoxin; Que, Jianwen

    2017-01-01

    In several organ systems the transitional zone between different types of epithelia is a hotspot for pre-neoplastic metaplasia and malignancy1–3. However, the cell-of-origin for the metaplastic epithelium and subsequent malignancy, remains obscure1–3. In the case of Barrett’s oesophagus (BE), intestinal metaplasia occurs at the gastro-oesophageal junction, where stratified squamous epithelium transitions into simple columnar cells4. Based on different experimental models, several alternative cell types have been proposed as the source of the metaplasia, but in all cases the evidence is inconclusive and no model completely mimics BE with the presence of intestinal goblet cells5–8. Here, we describe a novel transitional columnar epithelium with distinct basal progenitor cells (p63+ KRT5+ KRT7+) in the squamous-columnar junction (SCJ) in the upper gastrointestinal tract of the mouse. We use multiple models and lineage tracing strategies to show that this unique SCJ basal cell population serves as a source of progenitors for the transitional epithelium. Moreover, upon ectopic expression of CDX2 these transitional basal progenitors differentiate into intestinal-like epithelium including goblet cells, thus reproducing Barrett’s metaplasia. A similar transitional columnar epithelium is present at the transitional zones of other mouse tissues, including the anorectal junction, and, importantly, at the gastro-oesophageal junction in the human gut. Acid reflux-induced oesophagitis and the multilayered epithelium (MLE) believed to be a precursor of BE are both characterized by the expansion of the transitional basal progenitor cells. Taken together our findings reveal the presence of a previously unidentified transitional zone in the epithelium of the upper gastrointestinal tract and provide evidence that the p63+ KRT7+ basal cells in this zone are the cell-of-origin for MLE and BE. PMID:29019984

  16. Cell reprogramming modelled as transitions in a hierarchy of cell cycles

    International Nuclear Information System (INIS)

    Hannam, Ryan; Annibale, Alessia; Kühn, Reimer

    2017-01-01

    We construct a model of cell reprogramming (the conversion of fully differentiated cells to a state of pluripotency, known as induced pluripotent stem cells, or iPSCs) which builds on key elements of cell biology viz. cell cycles and cell lineages. Although reprogramming has been demonstrated experimentally, much of the underlying processes governing cell fate decisions remain unknown. This work aims to bridge this gap by modelling cell types as a set of hierarchically related dynamical attractors representing cell cycles. Stages of the cell cycle are characterised by the configuration of gene expression levels, and reprogramming corresponds to triggering transitions between such configurations. Two mechanisms were found for reprogramming in a two level hierarchy: cycle specific perturbations and a noise induced switching. The former corresponds to a directed perturbation that induces a transition into a cycle-state of a different cell type in the potency hierarchy (mainly a stem cell) whilst the latter is a priori undirected and could be induced, e.g. by a (stochastic) change in the cellular environment. These reprogramming protocols were found to be effective in large regimes of the parameter space and make specific predictions concerning reprogramming dynamics which are broadly in line with experimental findings. (paper)

  17. Development and demonstration of use of methane/hydrogen blends as fuel in existing methane-driven buses; Utveckling och demonstration av anvaendning av metan/vaetgasblandningar som braensle i befintliga metangasdrivna bussar

    Energy Technology Data Exchange (ETDEWEB)

    Joensson, Owe

    2006-10-15

    }-emissions than using pure hydrogen in e.g. fuel cell vehicles. NO{sub x}-emissions have proved to be extremely sensitive to the adjustment of the engine. The on-road emissions have proved to increase compared to natural gas operation when using 25% hydrogen addition. The cause for this is the control system of the engine (open loop control) and a slightly inaccurate reprogramming of the engine control system when going from natural gas to Hythane 25. Both of the hydrogen mixtures that have been used in the Malmoe project have been within the limits stated in the national specification for natural gas. This has facilitated the regulatory scope of the project since no special permits for operation of the buses had to be obtained. The two buses have covered more than 160,000 km in the project without any operational problems caused by the hydrogen addition. The drivability of the vehicles has been improved through the hydrogen addition and the drivers are thus very satisfied with the vehicles and the project. The activities in the project was finalised in December 2005 but the operation of the buses will continue using hydrogen/natural gas blends. Plans now exist to convert the major part of the CNG bus fleet in Malmoe to hydrogen/natural gas blends. This would make it the biggest bus fleet in the world using hydrogen addition.

  18. Increasing Capacity of Intersections with Transit Priority

    Directory of Open Access Journals (Sweden)

    Yanxi Hao

    2016-12-01

    Full Text Available Dedicated bus lane (DBL and transit signal priority (TSP are two effective and low-cost ways of improving the reliability of transits. However, these strategies reduce the capacity of general traffic. This paper presents an integrated optimization (IO model to improve the performance of intersections with dedicated bus lanes. The IO model integrated geometry layout, main-signal timing, pre-signal timing and transit priority. The optimization problem is formulated as a Mix-Integer-Non-Linear-Program (MINLP that can be transformed into a Mix-Integer-Linear-Program (MILP and then solved by the standard branch-and-bound technique. The applicability of the IO model is tested through numerical experiment under different intersection layouts and traffic demands. A VISSIM micro simulation model was developed and used to evaluate the performance of the proposed IO model. The test results indicate that the proposed model can increase the capacity and reduce the delay of general traffic when providing priority to buses.

  19. Local advanced transitional cell cancer and squamous cell cancer of ...

    African Journals Online (AJOL)

    Case report: A 51-year-old man presented with a locally advanced squamous cell cancer of the periurethral tissues as well as an underlying isolated transitional cell cancer of the urethra. Chemotherapy with Gemcitabin and Cisplatinum together with local radiation to the pelvis and the perineum was given. There was ...

  20. A new Zero-Voltage-Transition PWM switching cell

    Energy Technology Data Exchange (ETDEWEB)

    Grigore, V. [Electronics and Telecommunications Faculty `Politebuica` University Bucharest (Romania); Kyyrae, J. [Helsinki University of Technology, Otaniemi (Finland): Institute of Intelligent Power Electronics

    1997-12-31

    In this paper a new Zero-Voltage-Transition (ZVT) PWM switching cell is presented. The proposed switching cell is composed of the normal hard-switched PWM cell (consisting of one active switch and one passive switch), plus an auxiliary circuit (consisting of one active switch and some reactive components). The auxiliary circuit is inactive during the ON and OFF intervals of the switches in the normal PWM switch. However, the transitions between the two states are controlled by the auxiliary circuit. Prior to turn-on, the voltage across the active switch in the PWM cell is forced to zero, thus the turn-on losses of the active switch are practically eliminated. At turn-off the auxiliary circuit behaves like a non-dissipative passive snubber reducing the turn-off losses to a great extent. Zero-Voltage-Transition switching technique almost eliminates switching losses. The active switch operates under ZVT conditions, the passive switch (diode) has a controlled reverse recovery, and the switch in the auxiliary circuit operates under Zero-Current-Switching (ZCS) conditions. (orig.) 6 refs.

  1. Empirical membrane lifetime model for heavy duty fuel cell systems

    Science.gov (United States)

    Macauley, Natalia; Watson, Mark; Lauritzen, Michael; Knights, Shanna; Wang, G. Gary; Kjeang, Erik

    2016-12-01

    Heavy duty fuel cells used in transportation system applications such as transit buses expose the fuel cell membranes to conditions that can lead to lifetime-limiting membrane failure via combined chemical and mechanical degradation. Highly durable membranes and reliable predictive models are therefore needed in order to achieve the ultimate heavy duty fuel cell lifetime target of 25,000 h. In the present work, an empirical membrane lifetime model was developed based on laboratory data from a suite of accelerated membrane durability tests. The model considers the effects of cell voltage, temperature, oxygen concentration, humidity cycling, humidity level, and platinum in the membrane using inverse power law and exponential relationships within the framework of a general log-linear Weibull life-stress statistical distribution. The obtained model is capable of extrapolating the membrane lifetime from accelerated test conditions to use level conditions during field operation. Based on typical conditions for the Whistler, British Columbia fuel cell transit bus fleet, the model predicts a stack lifetime of 17,500 h and a membrane leak initiation time of 9200 h. Validation performed with the aid of a field operated stack confirmed the initial goal of the model to predict membrane lifetime within 20% of the actual operating time.

  2. Measurements of a vortex transitional ndro Josephson memory cell

    International Nuclear Information System (INIS)

    Tahara, S.; Ishida, I.; Hidaka, M.; Nagasawa, S.; Ajisawa, Y.; Wada, Y.

    1988-01-01

    A novel vortex transitional NDRO Jospehson memory cell has been successfully fabricated and tested. The memory cell consists of two superconducting loops and a two-junction interferometer gate as a sense gate. The superconducting loop contains one Josephson junction and inductances, and stores single flux quantum. The memory cell employs vortex transitions in the superconducting loops for writing and reading data. The memory cell chips have been fabricated using niobium planarization process. The +-21 percent address signal current margin and the +-33 percent sense gate current margin have been obtained experimentally. The memory operation of the cell driven by the two-junction interferometer gates has been accurately demonstrated

  3. Loss of prostasin (PRSS8) in human bladder transitional cell carcinoma cell lines is associated with epithelial-mesenchymal transition (EMT)

    International Nuclear Information System (INIS)

    Chen, Li-Mei; Verity, Nicole J; Chai, Karl X

    2009-01-01

    The glycosylphosphatidylinositol (GPI)-anchored epithelial extracellular membrane serine protease prostasin (PRSS8) is expressed abundantly in normal epithelia and essential for terminal epithelial differentiation, but down-regulated in human prostate, breast, and gastric cancers and invasive cancer cell lines. Prostasin is involved in the extracellular proteolytic modulation of the epidermal growth factor receptor (EGFR) and is an invasion suppressor. The aim of this study was to evaluate prostasin expression states in the transitional cell carcinomas (TCC) of the human bladder and in human TCC cell lines. Normal human bladder tissues and TCC on a bladder cancer tissue microarray (TMA) were evaluated for prostasin expression by means of immunohistochemistry. A panel of 16 urothelial and TCC cell lines were evaluated for prostasin and E-cadherin expression by western blot and quantitative PCR, and for prostasin gene promoter region CpG methylation by methylation-specific PCR (MSP). Prostasin is expressed in the normal human urothelium and in a normal human urothelial cell line, but is significantly down-regulated in high-grade TCC and lost in 9 (of 15) TCC cell lines. Loss of prostasin expression in the TCC cell lines correlated with loss of or reduced E-cadherin expression, loss of epithelial morphology, and promoter DNA hypermethylation. Prostasin expression could be reactivated by demethylation or inhibition of histone deacetylase. Re-expression of prostasin or a serine protease-inactive variant resulted in transcriptional up-regulation of E-cadherin. Loss of prostasin expression in bladder transitional cell carcinomas is associated with epithelial-mesenchymal transition (EMT), and may have functional implications in tumor invasion and resistance to chemotherapy

  4. High prevalence of EMRSA-15 in Portuguese public buses: a worrisome finding.

    Directory of Open Access Journals (Sweden)

    Roméo Rocha Simões

    Full Text Available BACKGROUND: The nosocomial prevalence of methicillin resistant Staphylococcus aureus (MRSA in Portugal remains one of the highest in Europe and is currently around 50%. Transmission of S. aureus, including MRSA, occurs principally by direct human-to-human skin contact. However, S. aureus can survive for long periods on inanimate objects, which may represent an important reservoir for dissemination as well. METHODOLOGY/PRINCIPAL FINDINGS: Between May 2009 and February 2010, handrails of 85 public urban buses circulating in Oporto, Portugal, were screened for the occurrence of MRSA. Twenty-two (26% buses showed MRSA contamination. The molecular characterization of a total of 55 MRSA, by pulsed-field gel electrophoresis (PFGE, staphylococcal cassette chromosome (SCC mec typing, spa typing, and multilocus sequence typing (MLST, clustered the isolates into three clonal types. However, the overwhelming majority (n = 50; 91% of the isolates belonged to a single clone (PFGE A, spa types t747, t032, t025 or t020, ST22, SCCmec type IVh that exhibits the characteristics of the pandemic EMRSA-15, currently the major lineage circulating in Portuguese hospitals, namely in the Oporto region. Two additional clones were found but in much lower numbers: (i PFGE B, ST5, spa type t002, SCCmec IVa (n = 3, and (ii PFGE C, spa type t008, ST8, SCCmec IVa (n = 2. None of the 55 isolates was PVL positive. CONCLUSIONS/SIGNIFICANCE: Public buses in Oporto seem to be an important reservoir of MRSA of nosocomial origin, providing evidence that the major hospital-associated MRSA clone in Portugal is escaping from the primary ecological niche of hospitals to the community environment. Infection control measures are urgently warranted to limit the spread of EMRSA-15 to the general population and future studies are required to assess the eventual increase of MRSA in the Portuguese community, which so far remains low.

  5. Orange County Transit/traffic Management Integration And Traveler Information Project: Evaluation Plan

    OpenAIRE

    Hall, R.; Hickman, M.

    1996-01-01

    This document focuses on a Field Operational Test (FOT) to develop an integrated information system for transit and traffic management and for traveler information that relies on Global Positioning System (GPS) equipped buses as probe vehicles. The document provides the evaluation plan for the FOT. The plan covers three principal elements: 1) Institutional, TMC Operator and Bus Operator, 2) Public Knowledge and Perceptions, and 3) System performance. The document provides an overall evaluatio...

  6. Adopting Clean Fuels and Technologies on School Buses. Pollution and Health Impacts in Children.

    Science.gov (United States)

    Adar, Sara D; D'Souza, Jennifer; Sheppard, Lianne; Kaufman, Joel D; Hallstrand, Teal S; Davey, Mark E; Sullivan, James R; Jahnke, Jordan; Koenig, Jane; Larson, Timothy V; Liu, L J Sally

    2015-06-15

    More than 25 million American children breathe polluted air on diesel school buses. Emission reduction policies exist, but the health impacts to individual children have not been evaluated. Using a natural experiment, we characterized the exposures and health of 275 school bus riders before, during, and after the adoption of clean technologies and fuels between 2005 and 2009. Air pollution was measured during 597 trips on 188 school buses. Repeated measures of exhaled nitric oxide (FeNO), lung function (FEV1, FVC), and absenteeism were also collected monthly (1,768 visits). Mixed-effects models longitudinally related the adoption of diesel oxidation catalysts (DOCs), closed crankcase ventilation systems (CCVs), ultralow-sulfur diesel (ULSD), or biodiesel with exposures and health. Fine and ultrafine particle concentrations were 10-50% lower on buses using ULSD, DOCs, and/or CCVs. ULSD adoption was also associated with reduced FeNO (-16% [95% confidence interval (CI), -21 to -10%]), greater changes in FVC and FEV1 (0.02 [95% CI, 0.003 to 0.05] and 0.01 [95% CI, -0.006 to 0.03] L/yr, respectively), and lower absenteeism (-8% [95% CI, -16.0 to -0.7%]), with stronger associations among patients with asthma. DOCs, and to a lesser extent CCVs, also were associated with improved FeNO, FVC growth, and absenteeism, but these findings were primarily restricted to patients with persistent asthma and were often sensitive to control for ULSD. No health benefits were noted for biodiesel. Extrapolating to the U.S. population, changed fuel/technologies likely reduced absenteeism by more than 14 million/yr. National and local diesel policies appear to have reduced children's exposures and improved health.

  7. Loss of prostasin (PRSS8 in human bladder transitional cell carcinoma cell lines is associated with epithelial-mesenchymal transition (EMT

    Directory of Open Access Journals (Sweden)

    Chai Karl X

    2009-10-01

    Full Text Available Abstract Background The glycosylphosphatidylinositol (GPI-anchored epithelial extracellular membrane serine protease prostasin (PRSS8 is expressed abundantly in normal epithelia and essential for terminal epithelial differentiation, but down-regulated in human prostate, breast, and gastric cancers and invasive cancer cell lines. Prostasin is involved in the extracellular proteolytic modulation of the epidermal growth factor receptor (EGFR and is an invasion suppressor. The aim of this study was to evaluate prostasin expression states in the transitional cell carcinomas (TCC of the human bladder and in human TCC cell lines. Methods Normal human bladder tissues and TCC on a bladder cancer tissue microarray (TMA were evaluated for prostasin expression by means of immunohistochemistry. A panel of 16 urothelial and TCC cell lines were evaluated for prostasin and E-cadherin expression by western blot and quantitative PCR, and for prostasin gene promoter region CpG methylation by methylation-specific PCR (MSP. Results Prostasin is expressed in the normal human urothelium and in a normal human urothelial cell line, but is significantly down-regulated in high-grade TCC and lost in 9 (of 15 TCC cell lines. Loss of prostasin expression in the TCC cell lines correlated with loss of or reduced E-cadherin expression, loss of epithelial morphology, and promoter DNA hypermethylation. Prostasin expression could be reactivated by demethylation or inhibition of histone deacetylase. Re-expression of prostasin or a serine protease-inactive variant resulted in transcriptional up-regulation of E-cadherin. Conclusion Loss of prostasin expression in bladder transitional cell carcinomas is associated with epithelial-mesenchymal transition (EMT, and may have functional implications in tumor invasion and resistance to chemotherapy.

  8. Alternative Fuel News, Volume 4, Number 3

    Energy Technology Data Exchange (ETDEWEB)

    Ficker, C.

    2000-11-14

    This issue of Alternative Fuel News focuses on transit buses and refuse haulers. Many transit agencies and waste management companies are investigating alternatives to traditional diesel buses and refuse haulers.

  9. Characterization and speciation of fine particulate matter inside the public transport buses running on bio-diesel.

    Science.gov (United States)

    2009-09-01

    Air pollution with respect to particulate matter was investigated in Toledo, Ohio, USA, a : city of approximately 300,000, in 2009. Two study buses were selected to reflect typical : exposure conditions of passengers while traveling in the bus. Monit...

  10. HYDROGEN COMMERCIALIZATION: TRANSPORTATION FUEL FOR THE 21ST CENTURY

    Energy Technology Data Exchange (ETDEWEB)

    APOLONIO DEL TORO

    2008-05-27

    Since 1999, SunLine Transit Agency has worked with the U.S. Department of Energy (DOE), U.S. Department of Defense (DOD), and the U.S. Department of Transportation (DOT) to develop and test hydrogen infrastructure, fuel cell buses, a heavy-duty fuel cell truck, a fuel cell neighborhood electric vehicle, fuel cell golf carts and internal combustion engine buses operating on a mixture of hydrogen and compressed natural gas (CNG). SunLine has cultivated a rich history of testing and demonstrating equipment for leading industry manufacturers in a pre-commercial environment. Visitors to SunLine's "Clean Fuels Mall" from around the world have included government delegations and agencies, international journalists and media, industry leaders and experts and environmental and educational groups.

  11. Adopting Clean Fuels and Technologies on School Buses. Pollution and Health Impacts in Children

    Science.gov (United States)

    D’Souza, Jennifer; Sheppard, Lianne; Kaufman, Joel D.; Hallstrand, Teal S.; Davey, Mark E.; Sullivan, James R.; Jahnke, Jordan; Koenig, Jane; Larson, Timothy V.; Liu, L. J. Sally

    2015-01-01

    Rationale: More than 25 million American children breathe polluted air on diesel school buses. Emission reduction policies exist, but the health impacts to individual children have not been evaluated. Methods: Using a natural experiment, we characterized the exposures and health of 275 school bus riders before, during, and after the adoption of clean technologies and fuels between 2005 and 2009. Air pollution was measured during 597 trips on 188 school buses. Repeated measures of exhaled nitric oxide (FeNO), lung function (FEV1, FVC), and absenteeism were also collected monthly (1,768 visits). Mixed-effects models longitudinally related the adoption of diesel oxidation catalysts (DOCs), closed crankcase ventilation systems (CCVs), ultralow-sulfur diesel (ULSD), or biodiesel with exposures and health. Measurements and Main Results: Fine and ultrafine particle concentrations were 10–50% lower on buses using ULSD, DOCs, and/or CCVs. ULSD adoption was also associated with reduced FeNO (−16% [95% confidence interval (CI), −21 to −10%]), greater changes in FVC and FEV1 (0.02 [95% CI, 0.003 to 0.05] and 0.01 [95% CI, −0.006 to 0.03] L/yr, respectively), and lower absenteeism (−8% [95% CI, −16.0 to −0.7%]), with stronger associations among patients with asthma. DOCs, and to a lesser extent CCVs, also were associated with improved FeNO, FVC growth, and absenteeism, but these findings were primarily restricted to patients with persistent asthma and were often sensitive to control for ULSD. No health benefits were noted for biodiesel. Extrapolating to the U.S. population, changed fuel/technologies likely reduced absenteeism by more than 14 million/yr. Conclusions: National and local diesel policies appear to have reduced children’s exposures and improved health. PMID:25867003

  12. The effects of urban driving conditions on the operating characteristics of conventional and hybrid electric city buses

    International Nuclear Information System (INIS)

    Soylu, Seref

    2014-01-01

    Highlights: • Operating characteristics of conventional and hybrid electric buses were examined. • Recovery of braking energy offers an excellent opportunity to improve fuel economy. • Speed and altitude profiles of routes have dramatic impacts on the energy recovery. • Capacity of the auxiliary power source has a dramatic impact on the energy recovery. • Round-trip efficiency of the regenerative braking system was calculated to be 27%. - Abstract: The basic operating characteristics of a conventional bus (CB) and a hybrid electric bus (HEB) were examined under urban driving conditions. To perform this examination, real-time operating data from the buses were collected on the Campus-Return route of the Sakarya Municipality. The main characteristics examined were the traction, braking, engine, engine generator unit (EGU), motor/generator (M/G), and ultracapacitor (Ucap) energies and efficiencies of the buses. The route elevation profile and the frequency of stop-and-go operations of the buses were found to have dramatic impacts on the braking and traction energies of the buses. The declining profile of the Campus-Return route provided an excellent opportunity for energy recovery by the regenerative braking system of the HEB. However, owing to the limits on the capacities and efficiencies of the hybrid drive train components and the Ucap, the bus braking energies were not recovered completely. Braking energies as high as 2.2 kW h per micro-trip were observed, but less than 1 kW h of braking energy per micro-trip was converted to electricity by the M/G; the rest of the braking energy was wasted in frictional braking. The maximum energy recovered and stored in the Ucap per micro-trip was 0.5 kW h, but the amount of energy recovered and stored per micro-trip was typically less than 0.2 kW h for the entire route. The cumulative braking energy recovered and stored in the Ucap for the Campus-Return route was 52% of the available brake energy, which was 13.02 kW h

  13. Bluetooth wireless monitoring, diagnosis and calibration interface for control system of fuel cell bus in Olympic demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Hua, Jianfeng; Lin, Xinfan; Xu, Liangfei; Li, Jianqiu; Ouyang, Minggao [Tsinghua University, State Key Laboratory of Automotive Safety and Energy, Beijing100084 (China)

    2009-01-15

    With the worldwide deterioration of the natural environment and the fossil fuel crisis, the possible commercialization of fuel cell vehicles has become a hot topic. In July 2008, Beijing started a clean public transportation plan for the 29th Olympic games. Three fuel cell city buses and 497 other low-emission vehicles are now serving the Olympic core area and Beijing urban areas. The fuel cell buses will operate along a fixed bus line for 1 year as a public demonstration of green energy vehicles. Due to the specialized nature of fuel cell engines and electrified power-train systems, measurement, monitoring and calibration devices are indispensable. Based on the latest Bluetooth wireless technology, a novel Bluetooth universal data interface was developed for the control system of the fuel cell city bus. On this platform, a series of wireless portable control auxiliary systems have been implemented, including wireless calibration, a monitoring system and an in-system programming platform, all of which are ensuring normal operation of the fuel cell buses used in the demonstration. (author)

  14. Hybrid Electric Transit Bus

    Science.gov (United States)

    Viterna, Larry A.

    1997-01-01

    A government, industry, and university cooperative is developing an advanced hybrid electric city transit bus. Goals of this effort include doubling the fuel economy compared to current buses and reducing emissions to one-tenth of current EPA standards. Unique aspects of the vehicle's power system include the use of ultra-capacitors as an energy storage system, and a planned natural gas fueled turbogenerator developed from a small jet engine. Power from both the generator and energy storage system is provided to a variable speed electric motor attached to the rear axle. At over 15000 kg gross weight, this is the largest vehicle of its kind ever built using ultra-capacitor energy storage. This paper describes the overall power system architecture, the evolution of the control strategy, and its performance over industry standard drive cycles.

  15. Hydrogen fuelled buses: Italian ENEA research program

    International Nuclear Information System (INIS)

    Ambrosini, G.; Ciancia, A.; Pede, G.

    1993-01-01

    Current hydrogen automotive fuels research studies being conducted by ENEA (Italian Agency for New Technology, Energy and the Environment) are being targeted towards the development of hydrogen fueled vans and buses for use in highly polluted urban environments where the innovative vehicles' air pollution abatement characteristics would justify their high operating costs as compared with those of conventional automotive alternatives. The demonstration vehicle being used in the experimental studies and performance tests is a two liter minibus with a spark ignition engine power rated at 55 kW with gasoline operation and 45 kW with hydrogen. Detailed design notes are given regarding the retrofitting of the minibus chassis to house the aluminium gas storage tanks and the adaptation of the engine to operate with compressed hydrogen. Attention is given to efforts being made to resolve combustion control and fueling problems. Focus is on the progress being made in the development of an efficient and safe electronically controlled fuel injection system

  16. A new Zero-Current-Transition PWM switching cell

    Energy Technology Data Exchange (ETDEWEB)

    Grigore, V. [Electronics and Telecommunications Faculty, `Politechnica` University Bucharest (Romania); Kyyrae, J. [Helsinki University of Technology, Otaniemi (Finland): Institute of Intelligent Power Electronics

    1997-12-31

    In this paper a new Zero-Current-Transition (ZCT) PWM switching cell is presented. The proposed switching cell is composed of the normal hard-switched PWM cell (consisting of one active switch and one passive switch), plus as auxiliary circuit. The auxiliary circuit is inactive during the ON ad OFF intervals of the switches in the normal PWM switch. The transitions between the two states are controlled by the auxiliary circuit. Prior to turn-off, the current through the active switch in the PWM cell is forced to zero, thus the turn-off losses of the active switch are practically eliminated. At turn-on the auxiliary circuit slows down the growing rate of the current through the main switch. Thus, turn-on losses are also very much reduced. The active switch operates under ZCT conditions, the passive switch (diode) has a controlled reverse recovery, while the switch in the auxiliary circuit operates under Zero-Current-Switching (ZCS) conditions. (orig.) 3 refs.

  17. Real-world operation conditions and on-road emissions of Beijing diesel buses measured by using portable emission measurement system and electric low-pressure impactor.

    Science.gov (United States)

    Liu, Zhihua; Ge, Yunshan; Johnson, Kent C; Shah, Asad Naeem; Tan, Jianwei; Wang, Chu; Yu, Linxiao

    2011-03-15

    On-road measurement is an effective method to investigate real-world emissions generated from vehicles and estimate the difference between engine certification cycles and real-world operating conditions. This study presents the results of on-road measurements collected from urban buses which propelled by diesel engine in Beijing city. Two widely used Euro III emission level buses and two Euro IV emission level buses were chosen to perform on-road emission measurements using portable emission measurement system (PEMS) for gaseous pollutant and Electric Low Pressure Impactor (ELPI) for particulate matter (PM) number emissions. The results indicate that considerable discrepancies of engine operating conditions between real-world driving cycles and engine certification cycles have been observed. Under real-world operating conditions, carbon monoxide (CO) and hydrocarbon (HC) emissions can easily meet their respective regulations limits, while brake specification nitrogen oxide (bsNO(x)) emissions present a significant deviation from its corresponding limit. Compared with standard limits, the real-world bsNO(x) emission of the two Euro III emission level buses approximately increased by 60% and 120% respectively, and bsNO(x) of two Euro IV buses nearly twice standard limits because Selective Catalytic Reduction (SCR) system not active under low exhaust temperature. Particle mass were estimated via particle size distribution with the assumption that particle density and diameter is liner. The results demonstrate that nanometer size particulate matter make significant contribution to total particle number but play a minor role to total particle mass. It is suggested that specific certified cycle should be developed to regulate bus engines emissions on the test bench or use PEMS to control the bus emissions under real-world operating conditions. Copyright © 2010 Elsevier B.V. All rights reserved.

  18. The California experience : lessons learned and prospects for the future

    Energy Technology Data Exchange (ETDEWEB)

    Levin, J. [AC Transit, Oakland, CA (United States)

    2007-07-01

    AC Transit operates 650 hydrogen-powered mass transit buses that serve 1.5 million people in 13 cities in California. This presentation discussed the impact of the buses on public health, quality of life and cost savings. Hydrogen has been touted as a diversified and renewable energy supply that can provide energy independence and reduction in global warming. Mass transit systems have proven to be well suited for testing the limits of hydrogen-powered vehicles primarily because of the centralized fueling and maintenance structure. AC Transit began ZEbus testing in November 1999 and became involved in the California Fuel Cell Partnership in 2000. The NeBus test was performed in 2000, followed by the ISE/UTC Thor Bus in 2003/2004. The governor's inauguration of the zero emission buses was in January 2007. The lessons learned from the California experience were: (1) motivation must be for the right reason, (2) a champion is required, (3) community and political support is required, (4) capital investment is required, (5) a strong management team is required, (6) partners must be chosen wisely, (7) the end user or customer must be allowed to drive the design, (8) inform the public about plans, (9) evaluation is essential to industry-wide application, (10) all resources must be considered for outreach and education, (11) optimism is required to surpass challenges, (12) the technology should be promoted for future generations. The presentation concluded with comments on market value of hydrogen and fuel cell vehicles, their fuel efficiency, reliability and durability. tabs., figs.

  19. Itinerant vending of medicines inside buses in Nigeria: vending strategies, dominant themes and medicine-related information provided.

    Science.gov (United States)

    Yusuff, Kazeem B; Wassi Sanni, Abd'

    2011-07-01

    To determine vending strategies and marketing themes employed by itinerant bus vendors, and assess the accuracy and completeness of information provided on medicines being sold in an urban setting in Nigeria. Cross-sectional study and content analysis of itinerant vending of medicines inside buses recorded with a mobile telephone on purposively selected routes in a mega city with an estimated 18 million residents in southwestern Nigeria over a 2-month period. Two coders independently assessed 192 vending episodes by 56 vendors for 147 OTC and prescription medicines. Inter-rater reliability (Gwet AC1 =0.924; p<0.0001). Fourteen thousands and four hundred potential consumers encountered 192 recorded episodes of vending of medicines inside 192 buses within the study periods. Forty-four (78•5%) of the 56 vendors were females in the 30-45 years age bracket, were mostly (75%) attired in the local 'Iro and Buba' Ankara fabric and showed laminated identity cards (97.5%) issued by the local association for 'marketers' of medicines inside buses, markets, and motor parks. Of the 14400 consumers encountered inside buses during the study period, between 6.7% and 48.3% purchased the medicines promoted. Prayers against death from road traffic accidents and diseases of physical and / or meta-physical origins were the most frequently used (76•8%) ice-breaking opening statement / strategy to gain consumers' attention. Hematinics, multi-vitamins, simple analgesic, NSAIDs and corticosteroids were the most frequently vended medicines. Consumers' enquiries were related to dosing for children (51.8%), elderly (28.6%), and pregnancy (52.7%); and contra-indications during pregnancy (8.9%). Factual medicines information such as dose, frequency, potential side effects and contra-indications were not provided in majority of vending episodes. Itinerant vending of medicines and the use of misleading and melodramatic themes to secure high consumer patronage appear considerable in Nigeria

  20. Pancreatic stellate cells promote epithelial-mesenchymal transition in pancreatic cancer cells

    International Nuclear Information System (INIS)

    Kikuta, Kazuhiro; Masamune, Atsushi; Watanabe, Takashi; Ariga, Hiroyuki; Itoh, Hiromichi; Hamada, Shin; Satoh, Kennichi; Egawa, Shinichi; Unno, Michiaki; Shimosegawa, Tooru

    2010-01-01

    Research highlights: → Recent studies have shown that pancreatic stellate cells (PSCs) promote the progression of pancreatic cancer. → Pancreatic cancer cells co-cultured with PSCs showed loose cell contacts and scattered, fibroblast-like appearance. → PSCs decreased the expression of epithelial markers but increased that of mesenchymal markers, along with increased migration. → This study suggests epithelial-mesenchymal transition as a novel mechanism by which PSCs contribute to the aggressive behavior of pancreatic cancer cells. -- Abstract: The interaction between pancreatic cancer cells and pancreatic stellate cells (PSCs), a major profibrogenic cell type in the pancreas, is receiving increasing attention. There is accumulating evidence that PSCs promote the progression of pancreatic cancer by increasing cancer cell proliferation and invasion as well as by protecting them from radiation- and gemcitabine-induced apoptosis. Because epithelial-mesenchymal transition (EMT) plays a critical role in the progression of pancreatic cancer, we hypothesized that PSCs promote EMT in pancreatic cancer cells. Panc-1 and SUIT-2 pancreatic cancer cells were indirectly co-cultured with human PSCs isolated from patients undergoing operation for pancreatic cancer. The expression of epithelial and mesenchymal markers was examined by real-time PCR and immunofluorescent staining. The migration of pancreatic cancer cells was examined by scratch and two-chamber assays. Pancreatic cancer cells co-cultured with PSCs showed loose cell contacts and a scattered, fibroblast-like appearance. The expression of E-cadherin, cytokeratin 19, and membrane-associated β-catenin was decreased, whereas vimentin and Snail (Snai-1) expression was increased more in cancer cells co-cultured with PSCs than in mono-cultured cells. The migration of pancreatic cancer cells was increased by co-culture with PSCs. The PSC-induced decrease of E-cadherin expression was not altered by treatment with anti

  1. Walking School Buses as a Form of Active Transportation for Children--A Review of the Evidence

    Science.gov (United States)

    Smith, Liz; Norgate, Sarah H.; Cherrett, Tom; Davies, Nigel; Winstanley, Christopher; Harding, Mike

    2015-01-01

    Background: Walking school buses (WSBs) offer a potentially healthier way for children to get to school while reducing traffic congestion. A number of pressing societal challenges make it timely to evaluate evidence of their value. Methods: Studies that focused solely on WSBs were identified through online and manual literature searches. Twelve…

  2. New Britain, Conn. School District will Benefit from $125,000 EPA Rebate for Clean Emission School Buses

    Science.gov (United States)

    The New Britain, Conn. school district will benefit from a $125,000 US EPA rebate that will pay for retrofitted engines on seven older school buses so they would emit fewer pollutants that are linked to health problems such as asthma and lung damage.

  3. IL-10-produced by human transitional B-cells down-regulates CD86 expression on B-cells leading to inhibition of CD4+T-cell responses.

    Science.gov (United States)

    Nova-Lamperti, Estefania; Fanelli, Giorgia; Becker, Pablo D; Chana, Prabhjoat; Elgueta, Raul; Dodd, Philippa C; Lord, Graham M; Lombardi, Giovanna; Hernandez-Fuentes, Maria P

    2016-01-22

    A novel subset of human regulatory B-cells has recently been described. They arise from within the transitional B-cell subpopulation and are characterised by the production of IL-10. They appear to be of significant importance in regulating T-cell immunity in vivo. Despite this important function, the molecular mechanisms by which they control T-cell activation are incompletely defined. Here we show that transitional B-cells produced more IL-10 and expressed higher levels of IL-10 receptor after CD40 engagement compared to other B-cell subsets. Furthermore, under this stimulatory condition, CD86 expressed by transitional B-cells was down regulated and T-cell proliferation was reduced. We provide evidence to demonstrate that the down-regulation of CD86 expression by transitional B-cells was due to the autocrine effect of IL-10, which in turn leads to decreased T-cell proliferation and TNF-α production. This analysis was further extended to peripheral B-cells in kidney transplant recipients. We observed that B-cells from patients tolerant to the graft maintained higher IL-10 production after CD40 ligation, which correlates with lower CD86 expression compared to patients with chronic rejection. Hence, the results obtained in this study shed light on a new alternative mechanism by which transitional B-cells inhibit T-cell proliferation and cytokine production.

  4. IL-10-produced by human transitional B-cells down-regulates CD86 expression on B-cells leading to inhibition of CD4+T-cell responses

    Science.gov (United States)

    Nova-Lamperti, Estefania; Fanelli, Giorgia; Becker, Pablo D.; Chana, Prabhjoat; Elgueta, Raul; Dodd, Philippa C.; Lord, Graham M.; Lombardi, Giovanna; Hernandez-Fuentes, Maria P.

    2016-01-01

    A novel subset of human regulatory B-cells has recently been described. They arise from within the transitional B-cell subpopulation and are characterised by the production of IL-10. They appear to be of significant importance in regulating T-cell immunity in vivo. Despite this important function, the molecular mechanisms by which they control T-cell activation are incompletely defined. Here we show that transitional B-cells produced more IL-10 and expressed higher levels of IL-10 receptor after CD40 engagement compared to other B-cell subsets. Furthermore, under this stimulatory condition, CD86 expressed by transitional B-cells was down regulated and T-cell proliferation was reduced. We provide evidence to demonstrate that the down-regulation of CD86 expression by transitional B-cells was due to the autocrine effect of IL-10, which in turn leads to decreased T-cell proliferation and TNF-α production. This analysis was further extended to peripheral B-cells in kidney transplant recipients. We observed that B-cells from patients tolerant to the graft maintained higher IL-10 production after CD40 ligation, which correlates with lower CD86 expression compared to patients with chronic rejection. Hence, the results obtained in this study shed light on a new alternative mechanism by which transitional B-cells inhibit T-cell proliferation and cytokine production. PMID:26795594

  5. Relationship between transit time and mechanical properties of a cell through a stenosed microchannel.

    Science.gov (United States)

    Ye, Ting; Shi, Huixin; Phan-Thien, Nhan; Lim, Chwee Teck; Li, Yu

    2018-01-24

    The changes in the mechanical properties of a cell are not only the cause of some diseases, but can also be a biomarker for some disease states. In recent times, microfluidic devices with built-in constrictions have been widely used to measure these changes. The transit time in such devices, defined as the time that a cell takes to pass through a constriction, has been found to be a crucial factor associated with the cell mechanical properties. Here, we use smoothed dissipative particle dynamics (SDPD), a particle-based numerical method, to explore the relationship between the transit time and mechanical properties of a cell. Three expressions of the transit time are developed from our simulation data, with respect to the stenosed size of constrictions, the shear modulus and bending modulus of cells, respectively. We show that a convergent constriction (the inlet is wider than the outlet), and a sharp-corner constriction (the constriction outlet is narrow) are better in identifying the differences in the transit time of cells. Moreover, the transit time increases and gradually approaches a constant as the shear modulus of cells increases, but increases first and then decreases as the bending modulus increases. These results suggest that the mechanical properties of cells can indeed be measured by analyzing their transit time, based on the recommended microfluidic device.

  6. Wnt is necessary for mesenchymal to epithelial transition in colorectal cancer cells.

    Science.gov (United States)

    Schwab, Renate H M; Amin, Nancy; Flanagan, Dustin J; Johanson, Timothy M; Phesse, Toby J; Vincan, Elizabeth

    2018-03-01

    Metastasis underlies most colorectal cancer mortality. Cancer cells spread through the body as single cells or small clusters of cells that have an invasive, mesenchymal, nonproliferative phenotype. At the secondary site, they revert to a proliferative "tumor constructing" epithelial phenotype to rebuild a tumor. We previously developed a unique in vitro three-dimensional model, called LIM1863-Mph, which faithfully recapitulates these reversible transitions that underpin colorectal cancer metastasis. Wnt signaling plays a key role in these transitions and is initiated by the coupling of extracellular Wnt to Frizzled (FZD). Using the LIM1863-Mph model system we demonstrated that the Wnt receptor FZD7 is necessary for mesenchymal to epithelial transition (MET). Here we investigate the role of Wnt in MET. Wnt secretion is dependent on palmitoylation by Porcupine (PORC). A PORC inhibitor (IWP2) that prevents Wnt secretion, blocked the epithelial transition of mesenchymal LIM1863-Mph cells. Wnt gene array analysis identified several Wnts that are upregulated in epithelial compared with mesenchymal LIM1863-Mph cells, suggesting these ligands in MET. Wnt2B was the most abundant differentially expressed Wnt gene. Indeed, recombinant Wnt2B could overcome the IWP2-mediated block in epithelial transition of mesenchymal LIM1863-Mph cells. Wnt2B co-operates with Frizzled7 to mediate MET in colorectal cancer. Developmental Dynamics 247:521-530, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  7. CT differentiation of renal tumor invading parenchyma and pelvis: renal cell carcinoma vs transitional cell carcinoma

    International Nuclear Information System (INIS)

    Lee, Chang Hee; Cho, Seong Beum; Park, Cheol Min; Cha, In Ho; Chung, Kyoo Byung

    1994-01-01

    The differentiation between renal cell carcinoma(RCC) and transitional cell carcinoma(TCC) is important due to the different methods of treatment and prognosis. But occasionally it is difficult to draw a distinction between the two diseases when renal parenchyma and renal collecting systems are invaded simultaneously. We reviewed CT scans of 37 cases of renal cell carcinoma and 12 cases of transitional cell carcinoma which showed involvement of renal parenchyma and renal sinus fat on CT. Retrospective analysis was performed by 3 abdominal radiologists. Check points were renal contour bulging or reinform shape, location of mass center, intact parenchyma overlying the tumor, cystic change, calcification, LN metastasis, vessel invasion, and perirenal extention. There were renal contour bulging due to the tumor mass in 33 out of 37 cases of renal cell carcinoma, where a and nine of 12 cases of transitional cell carcinoma maintained the reinform appearance. This is significant statiscal difference between the two(P<0.005). Center of all TCCs were located in the renal sinus, and 24 out of 35 cases of RCC were located in the cortex(P<0.005). Thirty-six out of 37 cases of RCC lost the overlying parenchyma, where as 4 out of 9 cases of well enhanced TCC had intact overlying parenchyma(P<0.005) RCC showed uptic change within the tumor mags in 31 cases which was significanity higher than the 4 cases in TCC(P<0.05). CT findings of renal cell carcinoma are contour bulging, peripheral location, obliteration of parenchyma, and cystic change. Findings of transitional cell carcinoma are reinform appearance, central location within the kidney, intact overlying parenchyma, and rare cystic change

  8. CNG/diesel buses for Texas school districts

    International Nuclear Information System (INIS)

    Armstrong, J.H.

    1993-01-01

    At the present time, the preponderance of trucks, buses and other heavy duty vehicles are powered by diesel engines. The reasons for the change from gasoline to diesel engines are all basically economic, due to the longer life and lower operating costs of diesel engines, as compared to gasoline engines. This provides a compelling reason to continue to use these engines, even if powered by fuel other than diesel. A major strategy within the industry has been the various attempts to adapt diesel engines to alternative fuels. These conversions have been largely to either methanol or natural gas, with propane joining the race just recently. This strategy takes advantage of the remaining life of existing vehicles by converting engines rather than purchasing a new engine (and/or vehicle) designed for and dedicated to an alternate fuel. Although diesel engines have been converted to run on natural gas, there are substantial challenges that must be met. The following describes some of the technical approaches being used for diesel engine conversions

  9. Comparable Measures of Accessibility to Public Transport Using the General Transit Feed Specification

    Directory of Open Access Journals (Sweden)

    Jinjoo Bok

    2016-03-01

    Full Text Available Public transport plays a critical role in the sustainability of urban settings. The mass mobility and quality of urban lives can be improved by establishing public transport networks that are accessible to pedestrians within a reasonable walking distance. Accessibility to public transport is characterized by the ease with which inhabitants can reach means of transportation such as buses or metros. By measuring the degree of accessibility to public transport networks using a common data format, a comparative study can be conducted between different cities or metropolitan areas with different public transit systems. The General Transit Feed Specification (GTFS by Google Developers allows this by offering a common format based on text files and sharing the data set voluntarily produced and contributed by the public transit agencies of many participating cities around the world. This paper suggests a method to assess and compare public transit accessibility in different urban areas using the GTFS feed and demographic data. To demonstrate the value of the new method, six examples of metropolitan areas and their public transit accessibility are presented and compared.

  10. Overview about the fuel cell bus demonstration programs CUTE, ECTOS and STEP

    International Nuclear Information System (INIS)

    Faltenbacher, M.; Fischer, M.; Eyerer, P.; Binder, M.; Schuckert, M.

    2004-01-01

    'Full text:' The paper will give an overview about the CUTE, ECTOS and STEP projects. The aim of the projects is to develop and demonstrate a emission-free and low-noise transport system, including the accompanying energy infrastructure, which has great potential for reducing the global greenhouse effect according to the Kyoto protocol, improving the quality of the atmosphere and life in densely populated areas and conserving fossil resources. For this purpose the application of the innovative hydrogen-based fuel cell technology is established by using fuel cell powered buses in an urban environment together with novel hydrogen production and support systems as part of a European Union wide demonstration scheme. The project demonstrates also to European Society the availability of the FC technology as a safe and reliable transportation technology. The major objectives are as follows: Demonstration of more than 20 fuel cell powered regular service buses over a period of two years in several European inner city areas to illustrate the different operating conditions to be found in Europe; Design, construction and operation of the necessary infrastructure for hydrogen production, including the required refuelling stations; Collection of findings concerning the construction and operating behaviour of hydrogen production for mobile use, and exchange of experiences including bus operation under differing conditions among the numerous participating companies; and, the research work of IKP and PE comprises the ecological analysis of the entire life cycle and comparison with conventional alternatives (diesel driven buses, CNG-buses). It also includes the economical analysis of the hydrogen infrastructure. First experiences from CUTE and ECTOS were presented. (author)

  11. Operational integrity using field buses; Integridade operacional utilizando barramentos de campo

    Energy Technology Data Exchange (ETDEWEB)

    Hennig, Carlos Henrique [Coester Automacao S.A., Sao Leopoldo, RS (Brazil)

    2004-07-01

    The device information is collected using standardized Filed Buses with high data transmission capacity, which allows the analysis of his operational status in real time. The quantity of information generated by the devices for the maintenance area is increasing and this data quantity transferred through the field bus should not interfere in the network performance to the point of degrade his control function. In this way, is presented a technique that can be used in different protocols, which allow sending of maintenance data using a small band of the communication channel. Operational integrity can be achieved using predictive maintenance techniques based on the collected data. (author)

  12. 49 CFR Appendix F to Part 222 - Diagnostic Team Considerations

    Science.gov (United States)

    2010-10-01

    ..., public safety or law enforcement, engineering personnel from the State agency responsible for grade... freight; 4. Accident history for each crossing under consideration; 5. School bus or transit bus use at... at any of the crossings? 14. If school buses or transit buses use crossings within the proposed quiet...

  13. Circumcaval ureter with synchronous ipsilateral transitional cell ...

    African Journals Online (AJOL)

    We report a case of concomitant transitional cell carcinoma (TCC) in a circumcaval ureter and invasive bladder cancer. The diagnosis was based on the findings of excretory urography (IVU) and contrast-enhanced computed tomography (CT). IVU showed a typical J-shaped deformity in the dilated right proximal ureteric ...

  14. Metastatic transitional cell carcinoma of the tibia radiologically mimicking osteosarcoma.

    LENUS (Irish Health Repository)

    Cunningham, Laurence Patrick

    2013-01-01

    We report a case of a 73-year-old lady with transitional cell carcinoma and no evidence of metastatic disease presenting with gradual weight loss, pretibial swelling and painful weightbearing. Investigations revealed a lesion of the right tibial diaphysis. The radiological and clinical appearance was that of primary osteosarcoma. Biopsy results revealed metastatic transitional cell carcinoma of the tibia. Intramedullary nailing was performed which relieved pain on weightbearing. The patient declined radiotherapy and was started on a palliative care regimen. This case illustrates the importance of histological diagnosis in the treatment of diaphyseal lesions.

  15. Report on FS survey for project of introduction of highly energy-efficient trolley buses into the Mexico Metropolitan Area in FY 1997; 1997 nendo chosa hokokusho (Mexico city eno sho energy gata trolley bus donyu project FS chosa)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Traffic jam and air pollution by automobiles are currently getting severe in the Mexico Metropolitan Area. Trolley buses were introduced for improving the environment more than ten years ago. Vehicles become too old for use, and their energy efficiency is low. In this project, 200 highly energy-efficient trolley buses are introduced to replace old inefficient trolley buses, which results in the improved traffic convenience in the City and enhanced energy efficiency. The new energy-efficient trolley buses are made of energy-efficient control VVVF inverters produced and exported by MELCO (Mitsubishi Electric Corporation), energy-efficient motors by MELMEX (Mitsubishi Electric Corporation, Mexico), and bodies by MASA which is a major manufacturer of bus bodies. The objective of this research is to analyze the background of introduction of new energy-efficient trolley buses and the effects of the present project. The results of analysis are going to be utilized for future promotion of the Joint Implementation and Clean Development Mechanism. 30 refs., 30 figs., 24 tabs.

  16. Natural Resource Canada`s fuel cell R and D program

    Energy Technology Data Exchange (ETDEWEB)

    Hammerli, M; Beck, N R [Natural Resources Canada, Ottawa, ON (Canada)

    1998-05-01

    The rationale for focusing fuel cell technology on the Ballard Proton exchange Membrane (PEM) system is provided. As well, research into other fuel cell types supported by Natural Resources Canada are discussed. Fuel cells are electrochemical devices that convert a fuel and an oxidant directly into electricity. Five fuel cell technologies use hydrogen as the fuel: (1) the alkaline fuel cell (AFC), (2) the proton exchange membrane fuel cell (PEMFC), (3) the phosphoric acid fuel cell (PAFC), (4) the molten carbonate fuel cell (MCFC), and (5) the solid oxide fuel cell (SOFC). The PEMFC is suitable for transportation applications because it does not contain a liquid electrolyte and it operates at about 80 degrees C. Trials on municipal bus systems are currently underway in Vancouver and Chicago. PEMFC stacks are supplied by Ballard Power Systems of Burnaby, BC, a recognized world leader in PEMFC technology. Daimler-Benz is demonstrating the methanol reformer on its NECAR-3, powered with a Ballard PEMFC. Ballard is also designing and producing two prototype fuel cell engines for the Ford Motor Company which will integrate them into its P2000 prototype vehicle platform. The Ballard technology is also suitable for distributed power generation up to about five MW, as well as for cogeneration, when fuelled with natural gas. Stuart Energy Systems (SES) has developed an advanced UNICELL-CLUSTER{sup T}M, which permits a direct coupling of the PV array to the electrolyser, a project which demonstrates the use of solar-electrolytic hydrogen production. SES is also designing a refuelling system for the BC Transit System in Vancouver for refuelling their three Zero Emission urban transit buses powered by Ballard fuel cell engines.

  17. Chicopee, Mass. School District will Benefit from $200,000 EPA Rebate to Clean Up Emissions from School Buses

    Science.gov (United States)

    A school district in Chicopee., Mass. will benefit from $200,000 from the US EPA that will pay for rebates to retrofit the engines on 10 older school buses so they would emit fewer pollutants that are linked to health problems such as asthma & lung damage.

  18. Next Generation Fuel Cell Technology for Passenger Cars and Buses

    OpenAIRE

    Mohrdieck, Dr.

    2009-01-01

    Daimler is presenting its latest fuel cell vehicle, the Mercedes-Benz B-Class F-CELL in 2009. Being one of the first series-produced fuel cell vehicles so far, the B-Class F-CELL will be a milestone on the road to commercialization of hydrogen-powered fuel cell vehicles. Equipped with advanced fuel cell technology it is suited for everyday operation and designed to fully meet customers´ expectations. From 2010 onwards, this zero emission vehicle is going to be operated by selected customers i...

  19. Transitional cell carcinoma express vitamin D receptors

    DEFF Research Database (Denmark)

    Hermann, G G; Andersen, C B

    1997-01-01

    Recently, vitamin D analogues have shown antineoplastic effect in several diseases. Vitamin D analogues exert its effect by interacting with the vitamin D receptor (VDR). Studies of VDR in transitional cell carcinoma (TCC) have not been reported. The purpose of the present study was therefore.......05). Similarly, also tumor grade appeared to be related to the number of cells expressing the receptor. Normal urothlium also expressed VDR but only with low intensity. Our study shows that TCC cells possess the VDR receptor which may make them capable to respond to stimulation with vitamin D, but functional...... studies of vitamin D's effect on TCC cells in vitro are necessary before the efficacy of treatment with vitamin D analogues in TCC can be evaluated in patients....

  20. Leukemoid reaction associated with transitional cell carcinoma: A ...

    African Journals Online (AJOL)

    Leukemoid reaction associated with transitional cell carcinoma: A case report ... Nigerian Journal of Clinical Practice ... At 3 months later, patient was admitted to our 21 22 hospital with the complaints of the left leg edema, diagnosed as pelvic

  1. Pilot testing of environment-friendly low-emission alternative drive components for city buses. Phase 1. Technical final report

    International Nuclear Information System (INIS)

    Doemeland, H.; Haase, G.; Sarnes, J.; Schultheis, S.; Schuenemann, M.; Strauss, A.; Voss, K.; Aepler, E.; Stachel, K.; Wolter, M.; Lenz, W.

    1993-05-01

    The report describes pilot tests of environment-friendly, low-emission city buses with alternative drive systems. The following problems are discussed: Natural gas as primary energy source, natural gas drives, safety requirements, measurement and testing technology for natural gas engines, environmental effects, operating concepts, operating cost. (HW) [de

  2. Load demand profile for a large charging station of a fleet of all-electric plug-in buses

    Directory of Open Access Journals (Sweden)

    Mario A. Rios

    2014-08-01

    Full Text Available This study proposes a general procedure to compute the load demand profile from a parking lot where a fleet of buses with electric propulsion mechanisms are charged. Such procedure is divided in three different stages, the first one models the daily energy utilisation of the batteries based on Monte Carlo simulations and route characteristics. The second one models the process in the charging station based on discrete event simulation of queues of buses served by a lot of available chargers. The third step computes the final demand profile in the parking lot because of the charging process based on the power consumption of batteries’ chargers and the utilisation of the available charges. The proposed procedure allows the computation of the number of required batteries’ chargers to be installed in a charging station placed at a parking lot in order to satisfy and ensure the operation of the fleet, the computation of the power demand profile and the peak load and the computation of the general characteristics of electrical infrastructure to supply the power to the station.

  3. Ways to improve the environmental conditions of their buses in operation on passenger routes of cities

    Directory of Open Access Journals (Sweden)

    Melnychuk S.V.

    2017-04-01

    Full Text Available The results of studies on operational and environmental parameters buses used on bus routes Zhitomir city. It uses statistical methods for determining the intensity of traffic, passenger traffic and ecology in traffic. To assess the environmental chosen stop with the greatest intensity of traffic, which is the probability of accumulation of pollution transport emissions that exceed permissible limits. Calculation of environmental pollution emission route for vehicles made stops street «Str. Hundreds of Heaven» «CUM», «vul. Hlibna» on the main trunk street Kievska. Results obtained environmental field experiments compared with the data defined calculation methods, based on the proposed use appropriate operational vehicles. The conclusions that indicate the seriousness of the problem and the urgency to address it. The system of environmental safety and road safety in Zhitomir requires significant improvements due to the increased quantities bus vehicles plying city routes. Recommendations to improve the ecological condition of intersections can be developed through the optimization of traffic using buses with environmentally improved operating parameters. Keywords: environmental and operational parameters; ecological safety; environmental assessment; intensity of traffic; passenger traffic; environmental conditions; operation; bus choice; stop.

  4. A human breast cell model of pre-invasive to invasive transition

    Energy Technology Data Exchange (ETDEWEB)

    Bissell, Mina J; Rizki, Aylin; Weaver, Valerie M.; Lee, Sun-Young; Rozenberg, Gabriela I.; Chin, Koei; Myers, Connie A.; Bascom, Jamie L.; Mott, Joni D.; Semeiks, Jeremy R.; Grate, Leslie R.; Mian, I. Saira; Borowsky, Alexander D.; Jensen, Roy A.; Idowu, Michael O.; Chen, Fanqing; Chen, David J.; Petersen, Ole W.; Gray, Joe W.; Bissell, Mina J.

    2008-03-10

    A crucial step in human breast cancer progression is the acquisition of invasiveness. There is a distinct lack of human cell culture models to study the transition from pre-invasive to invasive phenotype as it may occur 'spontaneously' in vivo. To delineate molecular alterations important for this transition, we isolated human breast epithelial cell lines that showed partial loss of tissue polarity in three-dimensional reconstituted-basement membrane cultures. These cells remained non-invasive; however, unlike their non-malignant counterparts, they exhibited a high propensity to acquire invasiveness through basement membrane in culture. The genomic aberrations and gene expression profiles of the cells in this model showed a high degree of similarity to primary breast tumor profiles. The xenograft tumors formed by the cell lines in three different microenvironments in nude mice displayed metaplastic phenotypes, including squamous and basal characteristics, with invasive cells exhibiting features of higher grade tumors. To find functionally significant changes in transition from pre-invasive to invasive phenotype, we performed attribute profile clustering analysis on the list of genes differentially expressed between pre-invasive and invasive cells. We found integral membrane proteins, transcription factors, kinases, transport molecules, and chemokines to be highly represented. In addition, expression of matrix metalloproteinases MMP-9,-13,-15,-17 was up regulated in the invasive cells. Using siRNA based approaches, we found these MMPs to be required for the invasive phenotype. This model provides a new tool for dissection of mechanisms by which pre-invasive breast cells could acquire invasiveness in a metaplastic context.

  5. Txatarra: vivienda transitoria con buses de transporte público

    Directory of Open Access Journals (Sweden)

    Juan Pablo Arenas Vargas

    2011-07-01

    Full Text Available El presente análisis del proyecto Casa Linda parte de una exploración conceptual en torno a un hábitat sostenible, mediante la generación de un tipo de vivienda transitoria que reutiliza buses de transporte público destinados a ser reducidos a chatarra. La necesidad de replantear la labor de configurar espacios con materiales y formas predeterminados llevó a los autores a comprender cómo resultan insuficientes los medios tradicionales de construcción, en los que se acostumbra emplear materias primas en presentaciones estandarizadas y con acabados predefinidos que se adaptan a los requerimientos y necesidades del proyecto. Enfrentar el proyecto a partir del reciclaje de materiales y objetos (chatarra, de diversas dimensiones y en variadas condiciones, generó un proceso cuya característica principal es la imposibilidad de anticipar con exactitud los procesos constructivos y los acabados finales.

  6. Cell Phenotype Transitions in Cardiovascular Calcification

    Directory of Open Access Journals (Sweden)

    Luis Hortells

    2018-03-01

    Full Text Available Cardiovascular calcification was originally considered a passive, degenerative process, however with the advance of cellular and molecular biology techniques it is now appreciated that ectopic calcification is an active biological process. Vascular calcification is the most common form of ectopic calcification, and aging as well as specific disease states such as atherosclerosis, diabetes, and genetic mutations, exhibit this pathology. In the vessels and valves, endothelial cells, smooth muscle cells, and fibroblast-like cells contribute to the formation of extracellular calcified nodules. Research suggests that these vascular cells undergo a phenotypic switch whereby they acquire osteoblast-like characteristics, however the mechanisms driving the early aspects of these cell transitions are not fully understood. Osteoblasts are true bone-forming cells and differentiate from their pluripotent precursor, the mesenchymal stem cell (MSC; vascular cells that acquire the ability to calcify share aspects of the transcriptional programs exhibited by MSCs differentiating into osteoblasts. What is unknown is whether a fully-differentiated vascular cell directly acquires the ability to calcify by the upregulation of osteogenic genes or, whether these vascular cells first de-differentiate into an MSC-like state before obtaining a “second hit” that induces them to re-differentiate down an osteogenic lineage. Addressing these questions will enable progress in preventative and regenerative medicine strategies to combat vascular calcification pathologies. In this review, we will summarize what is known about the phenotypic switching of vascular endothelial, smooth muscle, and valvular cells.

  7. Cell-State Transitions Regulated by SLUG Are Critical for Tissue Regeneration and Tumor Initiation

    Directory of Open Access Journals (Sweden)

    Sarah Phillips

    2014-05-01

    Full Text Available Perturbations in stem cell activity and differentiation can lead to developmental defects and cancer. We use an approach involving a quantitative model of cell-state transitions in vitro to gain insights into how SLUG/SNAI2, a key developmental transcription factor, modulates mammary epithelial stem cell activity and differentiation in vivo. In the absence of SLUG, stem cells fail to transition into basal progenitor cells, while existing basal progenitor cells undergo luminal differentiation; together, these changes result in abnormal mammary architecture and defects in tissue function. Furthermore, we show that in the absence of SLUG, mammary stem cell activity necessary for tissue regeneration and cancer initiation is lost. Mechanistically, SLUG regulates differentiation and cellular plasticity by recruiting the chromatin modifier lysine-specific demethylase 1 (LSD1 to promoters of lineage-specific genes to repress transcription. Together, these results demonstrate that SLUG plays a dual role in repressing luminal epithelial differentiation while unlocking stem cell transitions necessary for tumorigenesis.

  8. Design of durability test protocol for vehicular fuel cell systems operated in power-follow mode based on statistical results of on-road data

    Science.gov (United States)

    Xu, Liangfei; Reimer, Uwe; Li, Jianqiu; Huang, Haiyan; Hu, Zunyan; Jiang, Hongliang; Janßen, Holger; Ouyang, Minggao; Lehnert, Werner

    2018-02-01

    City buses using polymer electrolyte membrane (PEM) fuel cells are considered to be the most likely fuel cell vehicles to be commercialized in China. The technical specifications of the fuel cell systems (FCSs) these buses are equipped with will differ based on the powertrain configurations and vehicle control strategies, but can generally be classified into the power-follow and soft-run modes. Each mode imposes different levels of electrochemical stress on the fuel cells. Evaluating the aging behavior of fuel cell stacks under the conditions encountered in fuel cell buses requires new durability test protocols based on statistical results obtained during actual driving tests. In this study, we propose a systematic design method for fuel cell durability test protocols that correspond to the power-follow mode based on three parameters for different fuel cell load ranges. The powertrain configurations and control strategy are described herein, followed by a presentation of the statistical data for the duty cycles of FCSs in one city bus in the demonstration project. Assessment protocols are presented based on the statistical results using mathematical optimization methods, and are compared to existing protocols with respect to common factors, such as time at open circuit voltage and root-mean-square power.

  9. Laparoscopic-assisted nephroureterectomy after radical cystectomy for transitional cell carcinoma

    Directory of Open Access Journals (Sweden)

    Frederico R. Romero

    2006-12-01

    Full Text Available OBJECTIVE: To report our experience with laparoscopic-assisted nephroureterectomy for upper tract transitional cell carcinomas after radical cystectomy and urinary diversion. MATERIALS AND METHODS: Seven patients (53-72 years-old underwent laparoscopic-assisted nephroureterectomy 10 to 53 months after radical cystectomy for transitional cell carcinoma at our institution. Surgical technique, operative results, tumor features, and outcomes of all patients were retrospectively reviewed. RESULTS: Mean operative time was 305 minutes with a significant amount of time spent on the excision of the ureter from the urinary diversion. Estimate blood loss and length of hospital stay averaged 180 mL and 10.8 days, respectively. Intraoperative and postoperative complications occurred in two patients each. There was one conversion to open surgery. Pathology confirmed upper-tract transitional cell carcinoma in all cases. Metastatic disease occurred in two patients after a mean follow-up of 14.6 months. CONCLUSIONS: Nephrouretectomy following cystectomy is a complex procedure due to the altered anatomy and the presence of many adhesions. A laparoscopic-assisted approach can be performed safely in properly selected cases but does not yield the usual benefits seen with other laparoscopic renal procedures.

  10. General Information about Transitional Cell Cancer of the Renal Pelvis and Ureter

    Science.gov (United States)

    ... These cells can change shape and stretch without breaking apart. Transitional cell cancer starts in these cells. ... away. Extreme tiredness. Weight loss with no known reason. Painful or frequent urination. Tests that examine the ...

  11. Crash problem definition and safety benefits methodology for stability control for single-unit medium and heavy trucks and large-platform buses

    Science.gov (United States)

    2009-10-01

    This report presents the findings of a comprehensive engineering analysis of electronic stability control (ESC) and roll stability control (RSC) systems for single-unit medium and heavy trucks and large-platform buses. This report details the applica...

  12. Intermediate transport in Southeast Asia. [Carts, cycles, mini-buses

    Energy Technology Data Exchange (ETDEWEB)

    Meier, A.K.

    1977-06-01

    Traffic flows through the streets of Southeast Asian countries even though they are used for almost all aspects of human and animal existence. The carts, bicycles, tricycles, and motorcycles, motorized three-wheelers, mini-buses are the so-called intermediate-transport vehicles. It is upon this group of vehicles that a culture--constrained by its own unique economic, environmental, and technological factors--exerts its influence most directly toward the solution of the transport problem. Transportation fills more service roles in Southeast Asian cities than in Western cities. Communication facilities such as telephones and postal services are notoriously unreliable. The personal encounter is all important in social and business interactions in Southeast Asia. Each of the transport modes is examined in view of design and use in a number of specific cultural settings for the countries in Southeast Asia. Present use of intermediate transport in developed countries is discussed briefly, and its further development predicted--pointing out the health and conservation advantages. (MCW)

  13. Overexpression of microRNA-194 suppresses the epithelial-mesenchymal transition in targeting stem cell transcription factor Sox3 in endometrial carcinoma stem cells.

    Science.gov (United States)

    Gong, Baolan; Yue, Yan; Wang, Renxiao; Zhang, Yi; Jin, Quanfang; Zhou, Xi

    2017-06-01

    The epithelial-mesenchymal transition is the key process driving cancer metastasis. MicroRNA-194 inhibits epithelial-mesenchymal transition in several cancers and its downregulation indicates a poor prognosis in human endometrial carcinoma. Self-renewal factor Sox3 induces epithelial-mesenchymal transition at gastrulation and is also involved epithelial-mesenchymal transition in several cancers. We intended to determine the roles of Sox3 in inducing epithelial-mesenchymal transition in endometrial cancer stem cells and the possible role of microRNA-194 in controlling Sox3 expression. Firstly, we found that Sox3 and microRNA-194 expressions were associated with the status of endometrial cancer stem cells in a panel of endometrial carcinoma tissue, the CD133+ cell was higher in tumorsphere than in differentiated cells, and overexpression of microRNA-194 would decrease CD133+ cell expression. Silencing of Sox3 in endometrial cancer stem cell upregulated the epithelial marker E-cadherin, downregulated the mesenchymal marker vimentin, and significantly reduced cell invasion in vitro; overexpression of Sox3 reversed these phenotypes. Furthermore, we discovered that the expression of Sox3 was suppressed by microRNA-194 through direct binding to the Sox3 3'-untranslated region. Ectopic expression of microRNA-194 in endometrial cancer stem cells induced a mesenchymal-epithelial transition by restoring E-cadherin expression, decreasing vimentin expression, and inhibiting cell invasion in vitro. Moreover, overexpression of microRNA-194 inhibited endometrial cancer stem cell invasion or metastasis in vivo by injection of adenovirus microRNA-194. These findings demonstrate the novel mechanism by which Sox3 contributes to endometrial cancer stem cell invasion and suggest that repression of Sox3 by microRNA-194 may have therapeutic potential to suppress endometrial carcinoma metastasis. The cancer stem cell marker, CD133, might be the surface marker of endometrial cancer stem

  14. Technical evaluation report on the 120 Vac vital instrument buses and inverter Technical Specifications Issue B71

    International Nuclear Information System (INIS)

    St Leger-Barter, G.; White, R.L.

    1982-01-01

    The operation of a Pressurized Water Reactor (PWR) with one of its 120 Vac vital buses energized in an off-normal mode was analyzed. A Probabilistic Risk Assessment was made to determine the increment of risk by energizing a vital bus from an off-site source directly vs energizing it from its normal, uninterruptible source (i.e., a battery/inverter arrangement). The calculations were made based on uninterruptible source energized vital buses as the normal mode. The analysis indicated that a reduction in the incremental risk increase (caused by plant operation with a vital bus being energized in an off-normal mode) can be accomplished by limiting the time permitted in that condition. Currently, the time that a vital bus can be energized in the off-normal mode is not universally time-limited by plant Technical Specifications. Several alternatives for the reduction in incremental risk were examined and their value/impacts were derived. These data indicate that a recommendation be made for a Technical Specification time limitation of 72 hours per year for off-normal energizing a vital bus during operation of a PWR

  15. Intratumoral bidirectional transitions between epithelial and mesenchymal cells in triple-negative breast cancer.

    Science.gov (United States)

    Yamamoto, Mizuki; Sakane, Kota; Tominaga, Kana; Gotoh, Noriko; Niwa, Takayoshi; Kikuchi, Yasuko; Tada, Keiichiro; Goshima, Naoki; Semba, Kentaro; Inoue, Jun-Ichiro

    2017-06-01

    Epithelial-mesenchymal transition (EMT) and its reverse process, mesenchymal-epithelial transition MET, are crucial in several stages of cancer metastasis. Epithelial-mesenchymal transition allows cancer cells to move to proximal blood vessels for intravasation. However, because EMT and MET processes are dynamic, mesenchymal cancer cells are likely to undergo MET transiently and subsequently re-undergo EMT to restart the metastatic process. Therefore, spatiotemporally coordinated mutual regulation between EMT and MET could occur during metastasis. To elucidate such regulation, we chose HCC38, a human triple-negative breast cancer cell line, because HCC38 is composed of epithelial and mesenchymal populations at a fixed ratio even though mesenchymal cells proliferate significantly more slowly than epithelial cells. We purified epithelial and mesenchymal cells from Venus-labeled and unlabeled HCC38 cells and mixed them at various ratios to follow EMT and MET. Using this system, we found that the efficiency of EMT is approximately an order of magnitude higher than that of MET and that the two populations significantly enhance the transition of cells from the other population to their own. In addition, knockdown of Zinc finger E-box-binding homeobox 1 (ZEB1) or Zinc finger protein SNAI2 (SLUG) significantly suppressed EMT but promoted partial MET, indicating that ZEB1 and SLUG are crucial to EMT and MET. We also show that primary breast cancer cells underwent EMT that correlated with changes in expression profiles of genes determining EMT status and breast cancer subtype. These changes were very similar to those observed in EMT in HCC38 cells. Consequently, we propose HCC38 as a suitable model to analyze EMT-MET dynamics that could affect the development of triple-negative breast cancer. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  16. Rapid Fatal Outcome from Pulmonary Arteries Compression in Transitional Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Ioannis A. Voutsadakis

    2009-01-01

    Full Text Available Transitional cell carcinoma of the urinary bladder is a malignancy that metastasizes frequently to lymph nodes including the mediastinal lymph nodes. This occurrence may produce symptoms due to compression of adjacent structures such as the superior vena cava syndrome or dysphagia from esophageal compression. We report the case of a 59-year-old man with metastatic transitional cell carcinoma for whom mediastinal lymphadenopathy led to pulmonary artery compression and a rapidly fatal outcome. This rare occurrence has to be distinguished from pulmonary embolism, a much more frequent event in cancer patients, in order that proper and prompt treatment be initiated.

  17. Cell complexes of transition metals in biochemistry and medicine

    International Nuclear Information System (INIS)

    Voloshin, Ya.Z.; Varzatskij, O.A.; Bubnov, Yu.N.

    2007-01-01

    Basic directions and prospects of use of cell complexes of transition metals in medicine and biochemistry are considered: incapsulation of radioactive metal ions for radiotherapy and diagnostics; preparation of contrast compounds for magnetic resonance tomography, antidotes and pharmaceutical preparation of prolonged effect, preparations for boron-neutron-capture therapy of neoplasms, antioxidants; membrane transport of metal ions; study of interaction of cell metal complexes with nucleic acids; possibility of use of self-assembly of cell complexes for imitation of ligases and use of clathrochelates as linkers; design of inhibitors of viruses for AIDS therapy [ru

  18. Transition zone cells reach G2 phase before initiating elongation in maize root apex

    Directory of Open Access Journals (Sweden)

    M. Victoria Alarcón

    2017-06-01

    Full Text Available Root elongation requires cell divisions in the meristematic zone and cell elongation in the elongation zone. The boundary between dividing and elongating cells is called the transition zone. In the meristem zone, initial cells are continuously dividing, but on the basal side of the meristem cells exit the meristem through the transition zone and enter in the elongation zone, where they stop division and rapidly elongate. Throughout this journey cells are accompanied by changes in cell cycle progression. Flow cytometry analysis showed that meristematic cells are in cycle, but exit when they enter the elongation zone. In addition, the percentage of cells in G2 phase (4C strongly increased from the meristem to the elongation zone. However, we did not observe remarkable changes in the percentage of cells in cell cycle phases along the entire elongation zone. These results suggest that meristematic cells in maize root apex stop the cell cycle in G2 phase after leaving the meristem.

  19. Staghorn calculi and xanthogranulomatous pyelonephritis associated with transitional cell carcinoma

    Directory of Open Access Journals (Sweden)

    Chao-Wei Tseng

    2015-03-01

    Full Text Available Untreated staghorn calculi can cause xanthogranulomatous pyelonephritis (XGP, diminished renal function, and renal malignancy. Squamous cell carcinoma (SCC of the upper urinary tract is associated with kidney stones and chronic infection, but their association with transitional cell carcinoma (TCC has not been proven and has rarely been reported in literature. We present a rare case of staghorn calculi and XGP associated with TCC.

  20. COMPARISON OF PARALLEL AND SERIES HYBRID POWERTRAINS FOR TRANSIT BUS APPLICATION

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Zhiming [ORNL; Daw, C Stuart [ORNL; Smith, David E [ORNL; Jones, Perry T [ORNL; LaClair, Tim J [ORNL; Parks, II, James E [ORNL

    2016-01-01

    The fuel economy and emissions of both conventional and hybrid buses equipped with emissions aftertreatment were evaluated via computational simulation for six representative city bus drive cycles. Both series and parallel configurations for the hybrid case were studied. The simulation results indicate that series hybrid buses have the greatest overall advantage in fuel economy. The series and parallel hybrid buses were predicted to produce similar CO and HC tailpipe emissions but were also predicted to have reduced NOx tailpipe emissions compared to the conventional bus in higher speed cycles. For the New York bus cycle (NYBC), which has the lowest average speed among the cycles evaluated, the series bus tailpipe emissions were somewhat higher than they were for the conventional bus, while the parallel hybrid bus had significantly lower tailpipe emissions. All three bus powertrains were found to require periodic active DPF regeneration to maintain PM control. Plug-in operation of series hybrid buses appears to offer significant fuel economy benefits and is easily employed due to the relatively large battery capacity that is typical of the series hybrid configuration.

  1. Induced adult stem (iAS) cells and induced transit amplifying progenitor (iTAP) cells-a possible alternative to induced pluripotent stem (iPS) cells?

    Science.gov (United States)

    Heng, Boon Chin; Richards, Mark; Ge, Zigang; Shu, Yimin

    2010-02-01

    The successful derivation of iPSC lines effectively demonstrates that it is possible to reset the 'developmental clock' of somatic cells all the way back to the initial embryonic state. Hence, it is plausible that this clock may instead be turned back half-way to a less immature developmental stage that is more directly applicable to clinical therapeutic applications or for in vitro pharmacology/toxicology screening assays. Such a suitable developmental state is postulated to be either the putative transit amplifying progenitor stage or adult stem cell stage. It is hypothetically possible to reprogram mature and terminally differentiated somatic cells back to the adult stem cell or transit amplifying progenitor stage, in a manner similar to the derivation of iPSC. It is proposed that the terminology 'Induced Adult Stem Cells' (iASC) or 'Induced Transit Amplifying Progenitor Cells' (iTAPC) be used to described such reprogrammed somatic cells. Of particular interest, is the possibility of resetting the developmental clock of mature differentiated somatic cells of the mesenchymal lineage, explanted from adipose tissue, bone marrow and cartilage. The putative adult stem cell sub-population from which these cells are derived, commonly referred to as 'mesenchymal stem cells', are highly versatile and hold much therapeutic promise in regenerative medicine, as attested to by numerous human clinical trials and animal studies. Perhaps it may be appropriate to term such reprogrammed cells as 'Induced Mesenchymal Stem Cells' (iMSC) or as 'Induced Mesenchumal Progenitor Cells' (iMPC). Given that cells from the same organ/tissue will share some commonalities in gene expression, we hypothesize that the generation of iASC or iTAPC would be more efficient as compared to iPSC generation, since a common epigenetic program must exist between the reprogrammed cells, adult stem cell or progenitor cell types and terminally differentiated cell types from the same organ/tissue.

  2. Live cell plasma membranes do not exhibit a miscibility phase transition over a wide range of temperatures.

    Science.gov (United States)

    Lee, Il-Hyung; Saha, Suvrajit; Polley, Anirban; Huang, Hector; Mayor, Satyajit; Rao, Madan; Groves, Jay T

    2015-03-26

    Lipid/cholesterol mixtures derived from cell membranes as well as their synthetic reconstitutions exhibit well-defined miscibility phase transitions and critical phenomena near physiological temperatures. This suggests that lipid/cholesterol-mediated phase separation plays a role in the organization of live cell membranes. However, macroscopic lipid-phase separation is not generally observed in cell membranes, and the degree to which properties of isolated lipid mixtures are preserved in the cell membrane remain unknown. A fundamental property of phase transitions is that the variation of tagged particle diffusion with temperature exhibits an abrupt change as the system passes through the transition, even when the two phases are distributed in a nanometer-scale emulsion. We support this using a variety of Monte Carlo and atomistic simulations on model lipid membrane systems. However, temperature-dependent fluorescence correlation spectroscopy of labeled lipids and membrane-anchored proteins in live cell membranes shows a consistently smooth increase in the diffusion coefficient as a function of temperature. We find no evidence of a discrete miscibility phase transition throughout a wide range of temperatures: 14-37 °C. This contrasts the behavior of giant plasma membrane vesicles (GPMVs) blebbed from the same cells, which do exhibit phase transitions and macroscopic phase separation. Fluorescence lifetime analysis of a DiI probe in both cases reveals a significant environmental difference between the live cell and the GPMV. Taken together, these data suggest the live cell membrane may avoid the miscibility phase transition inherent to its lipid constituents by actively regulating physical parameters, such as tension, in the membrane.

  3. Emergency and Disaster Preparedness of School Transportation Staff and School Buses in the United States: Compliance With Recommendations for School Transportation Safety.

    Science.gov (United States)

    Olympia, Robert P; Weber, Christopher; Brady, Jodi; Ho, Susana

    2017-11-01

    The aim of the study was to determine the compliance of school transportation staff and school buses with recommendations for the safe transportation of children to and from school and school-related activities. An electronic questionnaire was distributed to school transportation staff represented by the International Brotherhood of Teamsters during the 2013-2014 academic year. Analysis was performed on 558 completed questionnaires (13% usable response rate). Responders had previous training in first aid (89%), basic life support (28%), and cardiopulmonary resuscitation (52%). Seventy-eight percent of school buses in our sample had restraint devices and 87% had seat belt cutters. Responders reported the immediate availability of the following on their bus: communication devices (81%), first aid kits (97%), fire extinguishers (89%), automated external defibrillators (1%), and epinephrine autoinjectors (2%). Thirty percent of responders have had no previous training in the management of emergencies such as trouble breathing, severe allergic reaction, seizures, cardiac arrest or unresponsiveness, and head, neck, or extremity trauma. Thirteen percent of responders are unfamiliar with or have had no previous training on protocols regarding emergency shelters and community evacuation plans in the event of a disaster. Variability exists in the compliance of school transportation staff and school buses with recommendations for the safe transportation of children. Areas for improvement were identified, such as educating school transportation staff in the recognition and initial management of pediatric emergencies, ensuring the presence of restraint devices, increasing the immediate availability of certain emergency medications and equipment, and familiarizing school transportation staff with designated emergency shelters and community evacuation plans.

  4. Considerations for the transition from fuel cell R ampersand D to manufacturing

    International Nuclear Information System (INIS)

    Cobb, M.A.

    1992-01-01

    There are a growing number of contractors within the present fuel cell community who have the potential of becoming high volume manufacturers of fuel cell power plants or components. Many are transitioning from basic research operations to manufacturing for the first time. Moving a product from the R ampersand D stage to a viable commercial product depends upon many factors. Some companies are more successful at it than others. We believe there is an underlying transition process from invention to market that is much the same for large, well established firms, as it is for start-ups. How well the process is understood and executed often determines the winners and losers in product commercialization. This paper presents a viewpoint on considerations for transitioning a new technology into commercial production and discusses some affects on organizational development

  5. Comparison of Life Cycle energy consumption and GHG emissions of natural gas, biodiesel and diesel buses of the Madrid transportation system

    International Nuclear Information System (INIS)

    García Sánchez, Juan Antonio; López Martínez, José María; Lumbreras Martín, Julio; Flores Holgado, Maria Nuria

    2012-01-01

    This paper presents a comparative study on the use of three after-treatment technologies: i) EGR + DPF, ii) SCR + Urea and iii) 3-way catalyst when implemented in urban buses, to determinate the energy requirements, greenhouse gas emissions (GHG), direct Land Use Change (dLUC), abiotic depletion of fossil energy by means of a Life Cycle Assessment (LCA). The process of production, conditioning and transporting of the fuels used by the buses (diesel, biodiesel (B100), a blended biodiesel at 20% (B20) and natural gas) were also analyzed (Well-to-Tank analysis) along with the environmental impact due to its combustion in the bus (Tank-to-Wheel analysis). The environmental impact of the manufacturing, maintenance and recycling process of the urban buses and exhaust after-treatment systems has also been evaluated. Main results shows that Life Cycle of SCR + Urea technology reduces environmental impact to a greater extent than its global Life Cycle increases it when gasoil is used resulting in a final balance more efficient than the other options, the same behavior is observed with the use of B20 and B100 but only when 0%dLUC is assumed since if the percentage of dLUC increases the effectiveness of the SCR + Urea technology in the reduction of environmental impact tend to decrease. -- Highlights: ► We examine the environmental impact caused by the Life Cycle of each technology, fossil fuel, biofuel and vehicle. ► Biodiesel environmental impact depends largely on land transformed for grow crops. ► Using SCR + Urea technology and gasoil as a fuel in the bus further reduces the environmental impact.

  6. Optimizing Performance of at-grade Intersection with Bus Rapid Transit Corridor and Heterogeneous Traffic

    Directory of Open Access Journals (Sweden)

    Hemant Kumar Sharma

    2012-06-01

    Full Text Available Bus Rapid Transit (BRT has emerged as a preferred mode of public transport in various countries all over the world for its cost effectiveness in construction as well as in operation and maintenance. The rapid transit feature of BRT is seen as a solution to many traffic problems in these countries. However, in developing countries like India, the right -of-way for most of the roads is restricted and traffic is heterogeneous in nature. Provision of BRT in existing right -of-way reduces the capacity available for other motorized traffic. As the buses travel with a certain frequency on dedicated bus- ways, the dedicated corridor remains unused for most of the period when other traffic on motorized vehicle (MV lanes suffers from congestion. The problem gets severe at intersections. However, if buses are operated in mixed traffic it is no more rapid transit. Hence, a solution is required to address this problem and optimize the performance of traffic as a whole. This paper presents the effect if dedicated bus-ways end at a reasonable distance before the stop line at a busy signalized at-grade intersection, and bus lanes (beyond that are made available to all the motorized vehicular traffic (heterogeneous traffic at intersection. The performance evaluation is done in terms of average queue length, maximum queue length, average delay time per vehicle, vehicle throughput, average speed in network and emission of Carbon monoxide CO, mono-nitrogen oxides NOx and Volatile organic compounds (VOC. It is observed that availability of bus lanes to other motorized traffic for a reasonable distance before intersection considerably reduces the average queue length, maximum queue length, average delay time per vehicle and emission per vehicle, while there is an increase in vehicle throughput and average speed of all the vehicles in the network. Thus it results in reduction of congestion and performance enhancement of at-grade intersections and network. Results of

  7. Road Safety Data, Collection, Transfer and Analysis DaCoTa. Factsheet Traffic safety basic facts 2010 : heavy goods vehicles and buses.

    NARCIS (Netherlands)

    Pace, J.-F. López de Cozar, E. Pérez-Fuster, P. Sanmartín, J. Kirk, A. Yannis, G. Evgenikos, P. Argyropoulou, E. Papantoniou, P. Broughton, J. Knowles, J. Brandstaetter, C. Candappa, N. Christoph, M. Vis, M. Haddak, M. & Moutengou, E.

    2012-01-01

    Heavy Goods Vehicles (HGVs) are defined as goods vehicles of over 3,5 tons maximum permissible gross vehicle weight. Road traffic accidents involving HGVs tend to be more severe than other accidents because of the great size and mass of these vehicles. Buses and coaches are included in this Basic

  8. Development and Evaluation of an Economic-Driving Assistance Program for Transit Vehicles

    Directory of Open Access Journals (Sweden)

    Baoxin Han

    2012-02-01

    Full Text Available This paper focuses on development and evaluation of an economic-driving assistance program for transit vehicles (EDTV which can minimize energy consumption, air pollution emission of buses, and improve the level of service of transit system as well. Taking advantage of the latest advances in information and communication technologies, the EDTV system can provide bus drivers with optimal recommended bus holding times at near-side bus stops and dynamic bus speed to adapt to the real-time traffic control plan at downstream intersections. In order to address the impacts of the stochastic variation of bus dwell time, the total link between adjacent intersections is divided into three parts: upstream of bus stop part; bus stop part; and downstream of bus stop part. The methods for calculating recommended parameters, including bus holding time and bus speed in each of the three parts are proposed based on real-time bus status and signal status at downstream intersections. A VISSIM-based simulation platform was designed and used for simulating and evaluating the proposed EDTV system. Extensive experimental analyses have shown that the proposed EDTV system can improve the performance of a transit system in terms of reducing fuel consumption, air pollution emissions and level of service of the transit system.

  9. Business Case for Fuel Cells 2016

    Energy Technology Data Exchange (ETDEWEB)

    Curtin, Sandra [Fuel Cell and Hydrogen Energy Association, Washington, DC (United States); Gangi, Jennifer [Fuel Cell and Hydrogen Energy Association, Washington, DC (United States); Benjamin, Thomas G. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-12-01

    The report provides an overview of recent private sector fuel cell installations at U.S. businesses as of December 31, 2016. This list is by no means exhaustive. Over the past few decades, hundreds of thousands of fuel cells have been installed around the world, for primary or backup power, as well as in various other applications including portable and emergency backup power. Fuel cells have also been deployed in other applications such as heat and electricity for homes and apartments, material handling, passenger vehicles, buses, and remote, off-grid sites.

  10. Analysis, operation and maintenance of a fuel cell/battery series-hybrid bus for urban transit applications

    Science.gov (United States)

    Bubna, Piyush; Brunner, Doug; Gangloff, John J.; Advani, Suresh G.; Prasad, Ajay K.

    The fuel cell hybrid bus (FCHB) program was initiated at the University of Delaware in 2005 to demonstrate the viability of fuel cell vehicles for transit applications and to conduct research and development to facilitate the path towards their eventual commercialization. Unlike other fuel cell bus programs, the University of Delaware's FCHB design features a battery-heavy hybrid which offers multiple advantages in terms of cost, performance and durability. The current fuel cell hybrid bus is driven on a regular transit route at the University of Delaware. The paper describes the baseline specifications of the bus with a focus on the fuel cell and the balance of plant. The fuel cell/battery series-hybrid design is well suited for urban transit routes and provides key operational advantages such as hydrogen fuel economy, efficient use of the fuel cell for battery recharging, and regenerative braking. The bus is equipped with a variety of sensors including a custom-designed cell voltage monitoring system which provide a good understanding of bus performance under normal operation. Real-time data collection and analysis have yielded key insights for fuel cell bus design optimization. Results presented here illustrate the complex flow of energy within the various subsystems of the fuel cell hybrid bus. A description of maintenance events has been included to highlight the issues that arise during general operation. The paper also describes several modifications that will facilitate design improvements in future versions of the bus. Overall, the fuel cell hybrid bus demonstrates the viability of fuel cells for urban transit applications in real world conditions.

  11. Recurrence of isolated transitional cell carcinoma in an orthotopic ...

    African Journals Online (AJOL)

    A.M. Moeen

    2015-11-10

    Nov 10, 2015 ... rare with less than 10 cases reported to date [2,3]. We present the case of a female patient with isolated recurrent transitional cell carcinoma (TCC) in an ileal neobladder, diagnosed 18 months after radical cystectomy and modified Hautmann ileal bladder substitution. E-mail address: moeen3@yahoo.com.

  12. A Low-Carbon-Based Bilevel Optimization Model for Public Transit Network

    Directory of Open Access Journals (Sweden)

    Xu Sun

    2013-01-01

    Full Text Available To satisfy the demand of low-carbon transportation, this paper studies the optimization of public transit network based on the concept of low carbon. Taking travel time, operation cost, energy consumption, pollutant emission, and traffic efficiency as the optimization objectives, a bilevel model is proposed in order to maximize the benefits of both travelers and operators and minimize the environmental cost. Then the model is solved with the differential evolution (DE algorithm and applied to a real network of Baoji city. The results show that the model can not only ensure the benefits of travelers and operators, but can also reduce pollutant emission and energy consumption caused by the operations of buses, which reflects the concept of low carbon.

  13. 26 CFR 48.4221-8 - Tax-free sales of tires, tubes, and tread rubber used on intercity, local, and school buses.

    Science.gov (United States)

    2010-04-01

    ... if the bus has a passenger seating capacity of at least 20 adults and the transportation is available... of a school. Incidental use (deadheading) of the school bus without passengers to or from a point to... used on intercity, local, and school buses. 48.4221-8 Section 48.4221-8 Internal Revenue INTERNAL...

  14. Staphylococcus aureus Lpl Lipoproteins Delay G2/M Phase Transition in HeLa Cells.

    Science.gov (United States)

    Nguyen, Minh-Thu; Deplanche, Martine; Nega, Mulugeta; Le Loir, Yves; Peisl, Loulou; Götz, Friedrich; Berkova, Nadia

    2016-01-01

    The cell cycle is an ordered set of events, leading to cell growth and division into two daughter cells. The eukaryotic cell cycle consists of interphase (G 1 , S, and G 2 phases), followed by the mitotic phase and G 0 phase. Many bacterial pathogens secrete cyclomodulins that interfere with the host cell cycle. In Staphylococcus aureus four cyclomodulins have been described so far that all represent toxins and are secreted into the culture supernatant. Here we show that the membrane-anchored lipoprotein-like proteins (Lpl), encoded on a genomic island called νSaα, interact with the cell cycle of HeLa cells. By comparing wild type and lpl deletion mutant it turned out that the lpl cluster is causative for the G2/M phase transition delay and also contributes to increased invasion frequency. The lipoprotein Lpl1, a representative of the lpl cluster, also caused G2/M phase transition delay. Interestingly, the lipid modification, which is essential for TLR2 signaling and activation of the immune system, is not necessary for cyclomodulin activity. Unlike the other staphylococcal cyclomodulins Lpl1 shows no cytotoxicity even at high concentrations. As all Lpl proteins are highly conserved there might be a common function that is accentuated by their multiplicity in a tandem gene cluster. The cell surface localized Lpls' suggests a correlation between G2/M phase transition delay and host cell invasion.

  15. Effect of Topology Structures on Synchronization Transition in Coupled Neuron Cells System

    International Nuclear Information System (INIS)

    Liang Li-Si; Zhang Ji-Qian; Xu Gui-Xia; Liu Le-Zhu; Huang Shou-Fang

    2013-01-01

    In this paper, by the help of evolutionary algorithm and using Hindmarsh—Rose (HR) neuron model, we investigate the effect of topology structures on synchronization transition between different states in coupled neuron cells system. First, we build different coupling structure with N cells, and found the effect of synchronized transition contact not only closely with the topology of the system, but also with whether there exist the ring structures in the system. In particular, both the size and the number of rings have greater effects on such transition behavior. Secondly, we introduce synchronization error to qualitative analyze the effect of the topology structure. Furthermore, by fitting the simulation results, we find that with the increment of the neurons number, there always exist the optimization structures which have the minimum number of connecting edges in the coupling systems. Above results show that the topology structures have a very crucial role on synchronization transition in coupled neuron system. Biological system may gradually acquire such efficient topology structures through the long-term evolution, thus the systems' information process may be optimized by this scheme. (interdisciplinary physics and related areas of science and technology)

  16. Thiol Redox Transitions in Cell Signaling: a Lesson from N-Acetylcysteine

    Directory of Open Access Journals (Sweden)

    Tiziana Parasassi

    2010-01-01

    Full Text Available The functional status of cells is under the control of external stimuli affecting the function of critical proteins and eventually gene expression. Signal sensing and transduction by messengers to specific effectors operate by post-translational modification of proteins, among which thiol redox switches play a fundamental role that is just beginning to be understood. The maintenance of the redox status is, indeed, crucial for cellular homeostasis and its dysregulation towards a more oxidized intracellular environment is associated with aberrant proliferation, ultimately related to diseases such as cancer, cardiovascular disease, and diabetes. Redox transitions occur in sensitive cysteine residues of regulatory proteins relevant to signaling, their evolution to metastable disulfides accounting for the functional redox switch. N-acetylcysteine (NAC is a thiol-containing compound that is able to interfere with redox transitions of thiols and, thus, in principle, able to modulate redox signaling. We here review the redox chemistry of NAC, then screen possible mechanisms to explain the effects observed in NAC-treated normal and cancer cells; such effects involve a modification of global gene expression, thus of functions and morphology, with a leitmotif of a switch from proliferation to terminal differentiation. The regulation of thiol redox transitions in cell signaling is, therefore, proposed as a new tool, holding promise not only for a deeper explanation of mechanisms, but indeed for innovative pharmacological interventions.

  17. Effects of calcitriol, seocalcitol, and medium-chain triglyceride on a canine transitional cell carcinoma cell line

    DEFF Research Database (Denmark)

    Kaewsakhorn, T.; Kisseberth, W.C.; Capen, C.C.

    2005-01-01

    Background: Transitional cell carcinoma (TCC) in dogs is associated with high morbidity and mortality. Calcitriol and its analog seocalcitol, combined with medium-chain triglyceride (MCT), have potential for the treatment of this disease. Materials and Methods: TCC cells were treated with calcitr...... inhibited TCC cell growth via induction of cell cycle arrest and MCT enhanced this effect. Therefore, calcitriol and seocalcitol with MCT may have therapeutic potential for canine bladder cancer....... with calcitriol or seocalcitol, alone or combined with MCT. Cell growth, cell cycle kinetics, vitamin D receptor (VDR) localization and expression, and Bcl-2 expression were measured. Results: Canine TCC expresses high levels of nuclear VDR. Furthermore, calcitriol and seocalcitol significantly inhibited cell...

  18. Hyperplasia of epithelium adjacent to transitional cell carcinoma can be induced by growth factors through paracrine pathways

    NARCIS (Netherlands)

    W.I. de Boer (Pim); J.M.J. Rebel (Annemarie); C.D.E.M. Thijssen (C. D E M); M. Vermey; Th.H. van der Kwast (Theo); A.J.M. van den Eijnden-van Raaij (Janny)

    1994-01-01

    textabstractHyperplasia of transitional cell epithelium adjacent to human transitional cell carcinomas (TCC) is a common finding in pathology. This hyperplasia may be a precancerous aberration. Alternatively, it has been suggested that the hyperplasia is due to paracrine action of tumour-derived

  19. Analysis, operation and maintenance of a fuel cell/battery series-hybrid bus for urban transit applications

    Energy Technology Data Exchange (ETDEWEB)

    Bubna, Piyush; Brunner, Doug; Gangloff, John J. Jr.; Advani, Suresh G.; Prasad, Ajay K. (Center for Fuel Cell Research, Department of Mechanical Engineering, University of Delaware, Newark, DE 19716 United States)

    2010-06-15

    The fuel cell hybrid bus (FCHB) program was initiated at the University of Delaware in 2005 to demonstrate the viability of fuel cell vehicles for transit applications and to conduct research and development to facilitate the path towards their eventual commercialization. Unlike other fuel cell bus programs, the University of Delaware's FCHB design features a battery-heavy hybrid which offers multiple advantages in terms of cost, performance and durability. The current fuel cell hybrid bus is driven on a regular transit route at the University of Delaware. The paper describes the baseline specifications of the bus with a focus on the fuel cell and the balance of plant. The fuel cell/battery series-hybrid design is well suited for urban transit routes and provides key operational advantages such as hydrogen fuel economy, efficient use of the fuel cell for battery recharging, and regenerative braking. The bus is equipped with a variety of sensors including a custom-designed cell voltage monitoring system which provide a good understanding of bus performance under normal operation. Real-time data collection and analysis have yielded key insights for fuel cell bus design optimization. Results presented here illustrate the complex flow of energy within the various subsystems of the fuel cell hybrid bus. A description of maintenance events has been included to highlight the issues that arise during general operation. The paper also describes several modifications that will facilitate design improvements in future versions of the bus. Overall, the fuel cell hybrid bus demonstrates the viability of fuel cells for urban transit applications in real world conditions. (author)

  20. A novel retinoic acid chalcone reverses epithelial‑mesenchymal transition in prostate cancer cells

    Directory of Open Access Journals (Sweden)

    Jian Zhong

    2015-06-01

    Full Text Available The present study was performed to investigate the effect of retinoic acid fluoro chalcone (RAFC on lipopolysaccharide (LPS induced epithelial-mesenchymal transition (EMT in PC3 and CWR22rv1 prostate cell lines. Lipo-polysaccharide (LPS was used to induce epithelial-mesenchymal transition in prostate carcinoma cell lines. The results revealed that treatment of PC3 and CWR22rv1 cells with LPS resulted in significant changes in the morphological features of the EMT. The mesenchymal marker, vimentin expression was significantly increased whereas the expression level of E‑cadherin was markedly decreased after the treatment. We also observed increased cell motility and higher level of transcription factor glioma‑associated oncogene homolog 1 (Gli1 expression on LPS treatment. Treatment of prostate cells with RAFC reversed the morphological changes induced by LPS in prostate cells. RAFC also reduced the expression of EMT markers induced by LPS and suppressed the Gli1 expression. The resultant effect of these changes was the suppression of motility and invasiveness of the prostrate cells. Thus, RAFC exhibited anti‑invasive effect on prostrate cells by inhibition of the EMT process via Hedgehog signaling pathway.

  1. King County Metro Battery Electric Bus Demonstration: Preliminary Project Results

    Energy Technology Data Exchange (ETDEWEB)

    2017-05-22

    The U.S. Federal Transit Administration (FTA) funds a variety of research projects that support the commercialization of zero-emission bus technology. To evaluate projects funded through these programs, FTA has enlisted the help of the National Renewable Energy Laboratory (NREL) to conduct third-party evaluations of the technologies deployed under the FTA programs. NREL works with the selected agencies to evaluate the performance of the zero-emission buses compared to baseline conventional buses in similar service. The evaluation effort will advance the knowledge base of zero-emission technologies in transit bus applications and provide 'lessons learned' to aid other fleets in incrementally introducing next generation zero-emission buses into their operations. This report provides preliminary performance evaluation results from a demonstration of three zero-emission battery electric buses at King County Metro in King County, Washington. NREL developed this preliminary results report to quickly disseminate evaluation results to stakeholders. Detailed evaluation results will be published in future reports.

  2. Dual-axis vapor cell for simultaneous laser frequency stabilization on disparate optical transitions

    Science.gov (United States)

    Jayakumar, Anupriya; Plotkin-Swing, Benjamin; Jamison, Alan O.; Gupta, Subhadeep

    2015-07-01

    We have developed a dual-axis ytterbium (Yb) vapor cell and used it to simultaneously address the two laser cooling transitions in Yb at wavelengths 399 nm and 556 nm, featuring the disparate linewidths of 2π × 29 MHz and 2π × 182 KHz, respectively. By utilizing different optical paths for the two wavelengths, we simultaneously obtain comparable optical densities suitable for saturated absorption spectroscopy for both the transitions and keep both the lasers frequency stabilized over several hours. We demonstrate that by appropriate control of the cell temperature profile, two atomic transitions differing in relative strength across a large range of over three orders of magnitude can be simultaneously addressed, making the device adaptable to a variety of spectroscopic needs. We also show that our observations can be understood with a simple theoretical model of the Yb vapor.

  3. Dual-axis vapor cell for simultaneous laser frequency stabilization on disparate optical transitions

    Energy Technology Data Exchange (ETDEWEB)

    Jayakumar, Anupriya, E-mail: anupriya@uw.edu; Plotkin-Swing, Benjamin; Jamison, Alan O.; Gupta, Subhadeep [Department of Physics, University of Washington, P.O. Box 351560, Seattle, Washington 98195-1560 (United States)

    2015-07-15

    We have developed a dual-axis ytterbium (Yb) vapor cell and used it to simultaneously address the two laser cooling transitions in Yb at wavelengths 399 nm and 556 nm, featuring the disparate linewidths of 2π × 29 MHz and 2π × 182 KHz, respectively. By utilizing different optical paths for the two wavelengths, we simultaneously obtain comparable optical densities suitable for saturated absorption spectroscopy for both the transitions and keep both the lasers frequency stabilized over several hours. We demonstrate that by appropriate control of the cell temperature profile, two atomic transitions differing in relative strength across a large range of over three orders of magnitude can be simultaneously addressed, making the device adaptable to a variety of spectroscopic needs. We also show that our observations can be understood with a simple theoretical model of the Yb vapor.

  4. Subcutaneous Transitional Cell Cancer After Percutaneous Nephrolithotomy: A Case Report

    Directory of Open Access Journals (Sweden)

    Lokman Ižrkilata

    2013-10-01

    Full Text Available Transitional cell carcinomas of the upper urinary tract are rare but, highly predisposing to tumoral seeding. Percutaneous lithotripsy (PNL recently has expanded the therapeutic choices for patients with kidney stones and gained popularity by urologic surgeons. Although unusual, renal collecting system tumours may be encountered during PNL. We present and discuss the clinical course of a 48 years old male patient who underwent PNL surgery for kidney stone in whom transitional cell carcinoma in the renal collecting system obscured by stone left undiagnosed. Three months later following PNL he admitted with a bulge on lumbar region. Excisional biopsy revealed carcinoma and therefore, he was directed to chemoradiotherapy and died 21 months later. Renal collecting system tumors undiagnosed during surgery may progress and demonstrate local invasion in a short period of time. Therefore, we recommend to take more caution during any percutaneous access and to exclude the possible existence of tumor.

  5. Analyzing the Relationship Between Bus Pollution Policies and Morbidity Using a Quasi-Experiment

    OpenAIRE

    Ngo, Nicole S.

    2015-01-01

    Abstract Transit buses are used by millions of commuters every day, but they emit toxic diesel fumes. In 1988, the U.S. Environmental Protection Agency implemented emission standards for transit buses, which have been continually updated. Yet there is no quantitative evidence of the health benefits from these bus pollution policies due to data constraints and confounding variables. In this study, a quasi-experiment is used to exploit the geographic and temporal variation in emission standards...

  6. Evaluation of city buses installed diesel particulate filter systems on fleet test; Diesel particulate filter system wo tosaishita rosen bus no soko chosa

    Energy Technology Data Exchange (ETDEWEB)

    Sudo, H [Japan Automobile Research Institute Inc., Tsukuba (Japan)

    1997-10-01

    An environmental air quality of suspended particulate matter is insufficient in the big city area. To reduce the particulate matter, improvement of engine and development of the Diesel Particulate Filter (DPF) system are carrying. The purpose of this report is to investigate a possibility of practical use of the city buses installed DPF systems. From March 1995, investigation for practical use of these DPF systems on a route buses was carried in regular service operation of the Tokyo and Yokohama Transportation Bureau. The investigation items are service situation, smoke density and preparation inspection. From the result for 2 years service operation, each DPF systems needed some failure correspondence. but these were not fatal problem on using the DPF system. Then the subject of relative to durability and reliability became clear, and the performance of a low particulate emission DPF system obtained the high value evaluation for users. 9 refs., 4 figs., 2 tabs.

  7. Fuel consumption reduction in urban buses by using power split transmissions

    International Nuclear Information System (INIS)

    Macor, Alarico; Rossetti, Antonio

    2013-01-01

    Highlights: • Fuel consumption is highly influenced by transmission layout and control. • Continuous Variable Transmission allows control of the working point of the engine. • Hydromechanical CVT was numerically tested and compared with usual mechanical solutions. • CVT solution proved to reduce fuel consumption, improving the I.C.E. mean efficiency. • Results obtained from standard emission test cycles: New York and Manhattan Buses. - Abstract: The reduction of fuel consumption of urban vehicles is one of the challenges of the society today. Many promising technologies such as hybrid electric vehicles and fuel cells are the focus of a lot of research and investments, but high costs prevent their development on a large scale, especially in heavy duty vehicles. Simpler solutions, such as continuously variable transmissions, are then interesting alternatives: they preserve some of the advantages of hybrid solutions significantly reducing the overall cost of the system. Since these technologies allow the decoupling of the engine’s velocity from that of the wheels, optimised management of the engine becomes feasible, leading to lower fuel consumption than that of traditional solutions. This work compares the hydromechanical transmission with a traditional power shift in an application where efficiency and comfort are required: a city bus. The performance of a vehicle with a dual stage hydromechanical transmission has been investigated by means of a model implemented in the AMESim environment. A second model of a vehicle with a power shift transmission has been taken as reference solution. During the simulation of two standard test cycles, the first vehicle showed the lower fuel consumption, due to its better engine management, and to the operation of the torque converter during starts, which lowers the efficiency of the reference vehicle

  8. Preliminary study on field buses for the control system of the high voltage of the ATLAS hadronic calorimeter; Etude preliminaire d`un reseau de terrain pour le systeme de controle des hautes tensions du calorimetre hadronique d`Atlas

    Energy Technology Data Exchange (ETDEWEB)

    Drevet, F.; Chadelas, R.; Montarou, G.

    1996-12-31

    We present here after a preliminary study on field buses for the control system of the high voltage of the photomultipliers of the TILECAL calorimeter. After some generalities, different commercial buses are reviewed (CAN, ARCET, WorldFIP, Profibus and LonWorks). The Profibus and LonWorks solution are more extensively studies as a possible solution for the high voltage system of the TILE hadronic calorimeter. (authors).

  9. Hydrogen fueling stations in Japan hydrogen and fuel cell demonstration project

    International Nuclear Information System (INIS)

    Koseki, K.; Tomuro, J.; Sato, H.; Maruyama, S.

    2004-01-01

    A new national demonstration project of fuel cell vehicles, which is called Japan Hydrogen and Fuel Cell Demonstration Project (JHFC Project), has started in FY2002 on a four-year plan. In this new project, ten hydrogen fueling stations have been constructed in Tokyo and Kanagawa area in FY2002-2003. The ten stations adopt the following different types of fuel and fueling methods: LPG reforming, methanol reforming, naphtha reforming, desulfurized-gasoline reforming, kerosene reforming, natural gas reforming, water electrolysis, liquid hydrogen, by-product hydrogen, and commercially available cylinder hydrogen. Approximately fifty fuel cell passenger cars and a fuel cell bus are running on public roads using these stations. In addition, two hydrogen stations will be constructed in FY2004 in Aichi prefecture where The 2005 World Exposition (EXPO 2005) will be held. The stations will service eight fuel cell buses used as pick-up buses for visitors. We, Engineering Advancement Association of Japan (ENAA), are commissioned to construct and operate a total of twelve stations by Ministry of Economy Trade and Industry (METI). We are executing to demonstrate or identify the energy-saving effect, reduction of the environmental footprint, and issues for facilitating the acceptance of hydrogen stations on the basis of the data obtained from the operation of the stations. (author)

  10. Why People Are Not Willing to Let Their Children Ride in Driverless School Buses: A Gender and Nationality Comparison

    Directory of Open Access Journals (Sweden)

    Emily C. Anania

    2018-02-01

    Full Text Available As driverless vehicles proliferate, it is possible that this technology will be applied in mass transport vehicles. School buses may be suited for autonomous operations as they follow set routes and schedules. However, a research gap exists in whether or not parents would be willing to have their children ride in autonomously operated school buses. The purpose of this study was to examine parents’ willingness to allow their child to ride in an autonomous school bus. Participant gender and nationality were also two independent variables, along with affect measures as a possible mediating variable. The research used a two-study approach. In study one, it was found that participants were less willing to have their child ride in a driverless school bus than a traditional human-operated vehicle. In study two, findings suggest a significant interaction between the type of driver, participant gender, and nationality. In general, American females were less willing than Indian females and overall, Americans were less willing than Indians in the driverless conditions. Affect was found to be a mediating variable, which suggests that emotions were playing a role in the responses of participants. The paper concludes with theoretical contributions, practical applications, and suggestions for future research.

  11. Kaempferol modulates the metastasis of human non-small cell lung cancer cells by inhibiting epithelial-mesenchymal transition

    Directory of Open Access Journals (Sweden)

    Meng Hang

    2015-06-01

    Full Text Available The present study was done to determine whether kaempferol, a natural polyphenol of the flavonoid family, affects Epithelial-Mesenchymal Transition (EMT in non-small cell lung cancer cells. Kaempferol not only inhibited cancer cell proliferation and migration in a dose-dependent manner but also modulated the expression of EMT-related proteins E-cadherin and vimentin which are indispensible to cellular motility, invasiveness and metastasis. These results indicate that kaempferol suppresses non-small cell lung cancer migration by modulating the expression of EMT proteins. Therefore, kaempferol may be useful as a potential anticancer agent for non-small cell lung cancer.

  12. 75 FR 53521 - Procedures for the Handling of Retaliation Complaints Under the National Transit Systems Security...

    Science.gov (United States)

    2010-08-31

    ... discrimination, demotion, discharge, suspension, threats, harassment, reprimand, retaliation, or any other manner... include school buses, charter, or intercity bus transportation or intercity passenger rail transportation... regular and continuous general or special transportation to the public, but does not include school buses...

  13. Evaluation of the use of bioethanol fuelled buses based on ambient air pollution screening and on-road measurements.

    Science.gov (United States)

    López-Aparicio, S; Hak, C

    2013-05-01

    Mitigation measures to reduce greenhouse gas emissions may have adverse effects on urban air quality and human exposure to harmful pollutants. The use of bioethanol fuelled vehicles is increasing worldwide and may create new undesired pollution effects. Different measurement campaigns were performed in a pilot study to contribute to the understanding of the consequences associated with the use of bioethanol blended fuel (E95) on a series of pollutants. Ambient screening measurements of NO2, O3, acetic acid, formaldehyde and acetaldehyde were performed at different urban locations, exposed and not exposed to the circulation of bioethanol buses. In addition, volatile organic compounds were measured at the exhaust pipe of a bioethanol fuelled bus, both under idling conditions (carbonyls; DNPH cartridge) and under on-road driving conditions applying online monitoring (PTR-TOF). Higher ambient acetaldehyde values were measured at locations exposed to bioethanol fuelled buses than at locations not exposed, and very high acetaldehyde and acetic acid values were measured from the exhaust pipe during driving conditions (acetaldehyde>150 ppm; acetic acid ≈ 20-30 ppm) and modelled at close distance to the bioethanol bus. Human exposure to high concentration of acetaldehyde is expected, and it may involve a significantly increased chance in developing cancer. The high concentration of acetic acid will involve odour annoyance and significant material degradation or corrosion. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Speeding the transition: Designing a fuel-cell hypercar

    Energy Technology Data Exchange (ETDEWEB)

    Williams, B.D.; Moore, T.C.; Lovins, A.B. [Rocky Mountain Inst., Snowmass, CO (United States). Hypercar Center

    1997-12-31

    A rapid transformation now underway in automotive technology could accelerate the transition to transportation powered by fuel cells. Ultralight, advanced-composite, low-drag, hybrid-electric hypercars--using combustion engines--could be three- to fourfold more efficient and one or two orders of magnitude cleaner than today`s cars, yet equally safe, sporty, desirable, and (probably) affordable. Further, important manufacturing advantages--including low tooling and equipment costs, greater mechanical simplicity, autobody parts consolidation, shorter product cycles, and reduced assembly effort and space--permit a free-market commercialization strategy. This paper discusses a conceptual hypercar powered by a proton-exchange-membrane fuel cell (PEMFC). It outlines the implications of platform physics and component selection for the vehicle`s mass budget and performance. The high fuel-to-traction conversion efficiency of the hypercar platform could help automakers overcome the Achilles` heel of hydrogen-powered vehicles: onboard storage. Moreover, because hypercars would require significantly less tractive power, and even less fuel-cell power, they could adopt fuel cells earlier, before fuel cells` specific cost, mass, and volume have fully matured. In the meantime, commercialization in buildings can help prepare fuel cells for hypercars. The promising performance of hydrogen-fueled PEMFC hypercars suggests important opportunities in infrastructure development for direct-hydrogen vehicles.

  15. Cyclin D1 affects epithelial–mesenchymal transition in epithelial ovarian cancer stem cell-like cells

    Directory of Open Access Journals (Sweden)

    Jiao J

    2013-06-01

    Full Text Available Jie Jiao,1,4 Lu Huang,1 Feng Ye,1 MinFeng Shi,2 XiaoDong Cheng,3 XinYu Wang,3 DongXiao Hu,3 Xing Xie,3 WeiGuo Lu31Women's Reproductive Health Laboratory of Zhejiang Province, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, 2Department of Gynaecology and Obstetrics, Changhai Hospital, the Second Military Medical University, Shanghai, 3Women's Reproductive Health Laboratory of Zhejiang Province, Department of Gynecologic Oncology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, 4Department of Gynaecology and Obstetrics, Hangzhou First People's Hospital, Hangzhou, People's Republic of ChinaBackground: The association of cancer stem cells with epithelial–mesenchymal transition (EMT is receiving attention. We found in our previous study that EMT existed from CD24- phenotype cells to their differentiated cells. It was shown that cyclin D1 functioned in sustaining self-renewal independent of CDK4/CDK6 activation, but its effect on the EMT mechanism in ovarian cancer stem cells is unclear.Methods: The anchorage-independent spheroids from ovarian adenocarcinoma cell line 3AO were formed in a serum-free medium. CD24- and CD24+ cells were isolated by fluorescence-activated cell sorting. Cell morphology, viability, apoptosis, and migratory ability were observed. Stem-related molecule Bmi-1, Oct-4 and EMT-related marker E-cadherin, and vimentin expressions were analyzed. Cyclin D1 expression in CD24- phenotype enriched spheroids was knocked down with small interfering RNA, and its effects on cell proliferation, apoptosis, migration ability, and EMT-related phenotype after transfection were observed. Results: In our study, CD24- cells presented stronger proliferative, anti-apoptosis capacity, and migratory ability, than CD24+ cells or parental cells. CD24- cells grew with a scattered spindle-shape within 3 days of culture and transformed into a cobblestone-like shape, identical to CD24+ cells or parental cells at 7

  16. Hypermethylation Is A Key Feature of the Transition of Multiple Myeloma to Plasma Cell Leukemia

    DEFF Research Database (Denmark)

    Walker, Brian A.; Wardell, Christopher P.; Boyd, Kevin D.

    2010-01-01

    in the transition of MM to PCL can be classified as either tumor suppressor genes, genes involved in cell-cell signaling, or as cell adhesion molecules. The further analysis of these genes will allow us to identify genes which are down-regulated through methylation and mediate the progression of MM to PCL allowing...... to malignant plasma cells and little is known about the genetic mechanisms mediating the final stages of this pathway. The methylation status of genes in myeloma can change as the malignancy progresses and as such identifying genes deregulated by methylation that mediate the progression of MM to PCL may offer...... the various cytogenetic subgroups of MM and in mediating the transition to PCL. Hypermethylation affects genes and pathways important in retaining plasma cells in the bone marrow as well as in their growth factor independent growth in the absence of stromal cell support. DisclosuresNo relevant conflicts...

  17. Increasing the solar cell power output by coating with transition metal-oxide nanorods

    International Nuclear Information System (INIS)

    Kuznetsov, I.A.; Greenfield, M.J.; Mehta, Y.U.; Merchan-Merchan, W.; Salkar, G.; Saveliev, A.V.

    2011-01-01

    Highlights: → Nanoparticles enhance solar cell efficiency. → Solar cell power increase by nanorod coating. → Metal-oxide nanorods are prepared in flames. → Molybdenum oxide nanorods effectively scatter light on solar cell surface. → Scattering efficiency depends on coating density. -- Abstract: Photovoltaic cells produce electric current through interactions among photons from an ambient light source and electrons in the semiconductor layer of the cell. However, much of the light incident on the panel is reflected or absorbed without inducing the photovoltaic effect. Transition metal-oxide nanoparticles, an inexpensive product of a process called flame synthesis, can cause scattering of light. Scattering can redirect photon flux, increasing the fraction of light absorbed in the thin active layer of silicon solar cells. This research aims to demonstrate that the application of transition metal-oxide nanorods to the surface of silicon solar panels can enhance the power output of the panels. Several solar panels were coated with a nanoparticle-methanol suspension, and the power outputs of the panels before and after the treatment were compared. The results demonstrate an increase in power output of up to 5% after the treatment. The presence of metal-oxide nanorods on the surface of the coated solar cells is confirmed by electron microscopy.

  18. Uncertainty in particle number modal analysis during transient operation of compressed natural gas, diesel, and trap-equipped diesel transit buses.

    Science.gov (United States)

    Holmén, Britt A; Qu, Yingge

    2004-04-15

    The relationships between transient vehicle operation and ultrafine particle emissions are not well-known, especially for low-emission alternative bus technologies such as compressed natural gas (CNG) and diesel buses equipped with particulate filters/traps (TRAP). In this study, real-time particle number concentrations measured on a nominal 5 s average basis using an electrical low pressure impactor (ELPI) for these two bus technologies are compared to that of a baseline catalyst-equipped diesel bus operated on ultralow sulfur fuel (BASE) using dynamometer testing. Particle emissions were consistently 2 orders of magnitude lower for the CNG and TRAP compared to BASE on all driving cycles. Time-resolved total particle numbers were examined in terms of sampling factors identified as affecting the ability of ELPI to quantify the particulate matter number emissions for low-emitting vehicles such as CNG and TRAP as a function of vehicle driving mode. Key factors were instrument sensitivity and dilution ratio, alignment of particle and vehicle operating data, sampling train background particles, and cycle-to-cycle variability due to vehicle, engine, after-treatment, or driver behavior. In-cycle variability on the central business district (CBD) cycle was highest for the TRAP configuration, but this could not be attributed to the ELPI sensitivity issues observed for TRAP-IDLE measurements. Elevated TRAP emissions coincided with low exhaust temperature, suggesting on-road real-world particulate filter performance can be evaluated by monitoring exhaust temperature. Nonunique particle emission maps indicate that measures other than vehicle speed and acceleration are necessary to model disaggregated real-time particle emissions. Further testing on a wide variety of test cycles is needed to evaluate the relative importance of the time history of vehicle operation and the hysteresis of the sampling train/dilution tunnel on ultrafine particle emissions. Future studies should

  19. Pediatric to Adult Care Transition: Perspectives of Young Adults With Sickle Cell Disease.

    Science.gov (United States)

    Porter, Jerlym S; Wesley, Kimberly M; Zhao, Mimi S; Rupff, Rebecca J; Hankins, Jane S

    2017-10-01

    The aim of this study was to explore perspectives of transition and transition readiness of young adult patients (YAs) with sickle cell disease (SCD) who have transitioned to adult health care. In all, 19 YAs with SCD (ages 18-30 years) participated in one of three focus groups and completed a brief questionnaire about transition topics. Transcripts were coded and emergent themes were examined using the social-ecological model of adolescent and young adult readiness for transition (SMART). Themes were consistent with most SMART components. Adult provider relationships and negative medical experiences emerged as salient factors. YAs ranked choosing an adult provider, seeking emergency care, understanding medications/medication adherence, knowing SCD complications, and being aware of the impact of health behaviors as the most important topics to include in transition programming. The unique perspectives of YAs can inform the development and evaluation of SCD transition programming by incorporating the identified themes. © The Author 2017. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  20. Final report : Calgary Transit customer satisfaction survey 2005

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-02-15

    This survey was conducted to measure the customer satisfaction of Calgary Transit users and gather information for further service improvements. The survey was conducted by telephone with a total of 500 current customers, and results were compared with previous surveys. The average number of trips per week among regular customers was 7.6, the lowest over the past 6 years. Twenty-six per cent of customers used the service more frequently due to higher gas prices, lack of a vehicle and the higher frequency of services. While most customers used buses, there was an increase in train usage in 2005, which was attributed to an increase in service frequency. Customers typically reported travelling during rush hour periods. Transit customers assigned a global score of 8.2 for service quality satisfaction and loyalty, which was consistent with previous scores. Seventy-two per cent of customers rated service quality as excellent or good. Approximately 1 in 5 customers perceived Calgary Transit to have improved over the previous year. Nearly half of the customers identified themselves as committed users of the service compared to other transportation methods, and most customers stated that having more service during peak hours and in new communities should be priorities. Sixty-four per cent of respondents supported fare increases to fund service additions. It was concluded that there was a significant increase in overall transit use in 2005, which may have been due to its perceived convenience and the influence of economic factors. It was noted that the increase has not affected customers' perceptions of service performance. 8 tabs., 9 figs.

  1. Stable knockdown of Kif5b in MDCK cells leads to epithelial–mesenchymal transition

    International Nuclear Information System (INIS)

    Cui, Ju; Jin, Guoxiang; Yu, Bin; Wang, Zai; Lin, Raozhou; Huang, Jian-Dong

    2015-01-01

    Polarization of epithelial cells requires vectorial sorting and transport of polarity proteins to apical or basolateral domains. Kif5b is the mouse homologue of the human ubiquitous Kinesin Heavy Chain (uKHC). To investigate the function of Kif5b in epithelial cells, we examined the phenotypes of Kif5b-deficient MDCK cells. Stable knockdown of Kif5b in MDCK cells resulted in reduced cell proliferation rate, profound changes in cell morphology, loss of epithelial cell marker, and gain of mesenchymal marker, as well as increased cell migration, invasion, and tumorigenesis abilities. E-cadherin and NMMIIA could interact with Kif5b in polarized MDCK cells, and their expression levels were decreased in Kif5b-deficient MDCK cells. Overexpression of E-cadherin and NMMIIA in Kif5b depleted MDCK cells could decrease mesenchymal marker expression and cell migration ability. These results indicate that stable knockdown of Kif5b in MDCK cells can lead to epithelial–mesenchymal transition, which is mediated by defective E-cadherin and NMMIIA expression. - Highlights: • Knockdown of Kif5b in MDCK cells resulted in reduced cell proliferation rate. • Kif5b deficient MDCK cells underwent epithelial–mesenchymal transition. • E-cadherin and NMMIIA could interact with Kif5b in polarized MDCK cells. • Decreased E-cadherin and NMMIIA levels mediate EMT in Kif5b deficient MDCK cells. • Overexpression of E-cadherin and NMMIIA reverse the effects of Kif5b knockdown

  2. Stable knockdown of Kif5b in MDCK cells leads to epithelial–mesenchymal transition

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Ju, E-mail: juzi.cui@gmail.com [The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, Beijing (China); Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR (China); Jin, Guoxiang; Yu, Bin [Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR (China); Wang, Zai [Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR (China); Institute of Clinical Medical Sciences, China-Japan Friendship Hospital, Beijing (China); Lin, Raozhou [Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR (China); Huang, Jian-Dong, E-mail: jdhuang@hku.hk [Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR (China); The Centre for Synthetic Biology Engineering Research, Shenzhen Institutes of Advanced Technology, Shenzhen (China)

    2015-07-17

    Polarization of epithelial cells requires vectorial sorting and transport of polarity proteins to apical or basolateral domains. Kif5b is the mouse homologue of the human ubiquitous Kinesin Heavy Chain (uKHC). To investigate the function of Kif5b in epithelial cells, we examined the phenotypes of Kif5b-deficient MDCK cells. Stable knockdown of Kif5b in MDCK cells resulted in reduced cell proliferation rate, profound changes in cell morphology, loss of epithelial cell marker, and gain of mesenchymal marker, as well as increased cell migration, invasion, and tumorigenesis abilities. E-cadherin and NMMIIA could interact with Kif5b in polarized MDCK cells, and their expression levels were decreased in Kif5b-deficient MDCK cells. Overexpression of E-cadherin and NMMIIA in Kif5b depleted MDCK cells could decrease mesenchymal marker expression and cell migration ability. These results indicate that stable knockdown of Kif5b in MDCK cells can lead to epithelial–mesenchymal transition, which is mediated by defective E-cadherin and NMMIIA expression. - Highlights: • Knockdown of Kif5b in MDCK cells resulted in reduced cell proliferation rate. • Kif5b deficient MDCK cells underwent epithelial–mesenchymal transition. • E-cadherin and NMMIIA could interact with Kif5b in polarized MDCK cells. • Decreased E-cadherin and NMMIIA levels mediate EMT in Kif5b deficient MDCK cells. • Overexpression of E-cadherin and NMMIIA reverse the effects of Kif5b knockdown.

  3. Ramp-related incidents involving wheeled mobility device users during transit bus boarding/alighting.

    Science.gov (United States)

    Frost, Karen L; Bertocci, Gina; Smalley, Craig

    2015-05-01

    To estimate the prevalence of wheeled mobility device (WhMD) ramp-related incidents while boarding/alighting a public transit bus and to determine whether the frequency of incidents is less when the ramp slope meets the proposed Americans with Disabilities Act (ADA) maximum allowable limit of ≤9.5°. Observational study. Community public transportation. WhMD users (N=414) accessing a public transit bus equipped with an instrumented ramp. Not applicable. Prevalence of boarding/alighting incidents involving WhMD users and associated ramp slopes; factors affecting incidents. A total of 4.6% (n=35) of WhMD users experienced an incident while boarding/alighting a transit bus. Significantly more incidents occurred during boarding (6.3%, n=26) than during alighting (2.2%, n=9) (Pboard/alight when the ramp slope exceeded the proposed ADA maximum allowable ramp slope was 5.1 (95% confidence interval, 2.9-9.0; P9.5° and ramps deployed to street level are associated with a higher frequency of incidents and provision of assistance. Transit agencies should increase awareness among bus operators of the effect kneeling and deployment location (street/sidewalk) have on the ramp slope. In addition, ramp components and the built environment may contribute to incidents. When prescribing WhMDs, skills training must include ascending/descending ramps at slopes encountered during boarding/alighting to ensure safe and independent access to public transit buses. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  4. Mesenchymal Stem Cells Induce Epithelial to Mesenchymal Transition in Colon Cancer Cells through Direct Cell-to-Cell Contact

    Directory of Open Access Journals (Sweden)

    Hidehiko Takigawa

    2017-05-01

    Full Text Available We previously reported that in an orthotopic nude mouse model of human colon cancer, bone marrow–derived mesenchymal stem cells (MSCs migrated to the tumor stroma and promoted tumor growth and metastasis. Here, we evaluated the proliferation and migration ability of cancer cells cocultured with MSCs to elucidate the mechanism of interaction between cancer cells and MSCs. Proliferation and migration of cancer cells increased following direct coculture with MSCs but not following indirect coculture. Thus, we hypothesized that direct contact between cancer cells and MSCs was important. We performed a microarray analysis of gene expression in KM12SM colon cancer cells directly cocultured with MSCs. Expression of epithelial-mesenchymal transition (EMT–related genes such as fibronectin (FN, SPARC, and galectin 1 was increased by direct coculture with MSCs. We also confirmed the upregulation of these genes with real-time polymerase chain reaction. Gene expression was not elevated in cancer cells indirectly cocultured with MSCs. Among the EMT-related genes upregulated by direct coculture with MSCs, we examined the immune localization of FN, a well-known EMT marker. In coculture assay in chamber slides, expression of FN was seen only at the edges of cancer clusters where cancer cells directly contacted MSCs. FN expression in cancer cells increased at the tumor periphery and invasive edge in orthotopic nude mouse tumors and human colon cancer tissues. These results suggest that MSCs induce EMT in colon cancer cells via direct cell-to-cell contact and may play an important role in colon cancer metastasis.

  5. A cost-benefit analysis of alternatively fueled buses with special considerations for V2G technology

    International Nuclear Information System (INIS)

    Shirazi, Yosef; Carr, Edward; Knapp, Lauren

    2015-01-01

    Motivated by climate, health and economic considerations, alternatively-fueled bus fleets have emerged worldwide. Two popular alternatives are compressed natural gas (CNG) and electric vehicles. The latter provides the opportunity to generate revenue through vehicle-to-grid (V2G) services if properly equipped. This analysis conducts a robust accounting of the costs of diesel, CNG and battery-electric powertrains for school buses. Both marginal and fleet-wide scenarios are explored. Results indicate that the marginal addition of neither a small CNG nor a small V2G-enabled electric bus is cost effective at current prices. Contrary to previous findings, a small V2G-enabled electric bus increases net present costs by $7,200/seat relative to diesel for a Philadelphia, PA school district. A small CNG bus increases costs by $1,200/seat relative to diesel. This analysis is the first to quantify and include the economic implications of cold temperature extremes on electric vehicle battery operations, and the lower V2G revenues that result. Additional costs and limitations imposed by electric vehicles performing V2G are frequently overlooked in the literature and are explored here. If a variety of technical, legal, and economic challenges are overcome, a future eBus may be economical. - Highlights: • We present a robust cost-benefit analysis of various bus technologies. • Diesel is a low-cost technology at current prices. • CNG represents slightly higher costs on a marginal bus basis. • V2G-enabled electric buses are not cost-effective at current prices. • We identify frequently overlooked costs and challenges to V2G implementation.

  6. Tumor budding cells, cancer stem cells and epithelial-mesenchymal transition-type cells in pancreatic cancer

    International Nuclear Information System (INIS)

    Karamitopoulou, Eva

    2013-01-01

    Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers with a 5-year survival rate of less than 5%. Moreover, PDAC escapes early detection and resists treatment. Multiple combinations of genetic alterations are known to occur in PDAC including mutational activation of KRAS, inactivation of p16/CDKN2A and SMAD4 (DPC4) and dysregulation of PTEN/PI3K/AKT signaling. Through their interaction with Wingless-INT pathway, the downstream molecules of these pathways have been implicated in the promotion of epithelial–mesenchymal transition (EMT). Emerging evidence has demonstrated that cancer stem cells (CSCs), small populations of which have been identified in PDAC, and EMT-type cells play critical roles in drug resistance, invasion, and metastasis in pancreatic cancer. EMT may be histologically represented by the presence of tumor budding which is described as the occurrence of single tumor cells or small clusters (<5) of dedifferentiated cells at the invasive front of gastrointestinal (including colorectal, oesophageal, gastric, and ampullary) carcinomas and is linked to poor prognosis. Tumor budding has recently been shown to occur frequently in PDAC and to be associated with adverse clinicopathological features and decreased disease-free and overall survival. The aim of this review is to present a short overview on the morphological and molecular aspects that underline the relationship between tumor budding cells, CSCs, and EMT-type cells in PDAC.

  7. Tumor budding cells, cancer stem cells and epithelial-mesenchymal transition-type cells in pancreatic cancer.

    Science.gov (United States)

    Karamitopoulou, Eva

    2012-01-01

    Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers with a 5-year survival rate of less than 5%. Moreover, PDAC escapes early detection and resists treatment. Multiple combinations of genetic alterations are known to occur in PDAC including mutational activation of KRAS, inactivation of p16/CDKN2A and SMAD4 (DPC4) and dysregulation of PTEN/PI3K/AKT signaling. Through their interaction with Wingless-INT pathway, the downstream molecules of these pathways have been implicated in the promotion of epithelial-mesenchymal transition (EMT). Emerging evidence has demonstrated that cancer stem cells (CSCs), small populations of which have been identified in PDAC, and EMT-type cells play critical roles in drug resistance, invasion, and metastasis in pancreatic cancer. EMT may be histologically represented by the presence of tumor budding which is described as the occurrence of single tumor cells or small clusters (<5) of dedifferentiated cells at the invasive front of gastrointestinal (including colorectal, oesophageal, gastric, and ampullary) carcinomas and is linked to poor prognosis. Tumor budding has recently been shown to occur frequently in PDAC and to be associated with adverse clinicopathological features and decreased disease-free and overall survival. The aim of this review is to present a short overview on the morphological and molecular aspects that underline the relationship between tumor budding cells, CSCs, and EMT-type cells in PDAC.

  8. Tumor Budding Cells, Cancer Stem Cells and Epithelial-Mesenchymal Transition-type Cells in Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Eva eKaramitopoulou

    2013-01-01

    Full Text Available Pancreatic ductal adenocarcinoma (PDAC is one of the most lethal cancers with a 5-year survival rate of less than 5%. Moreover, PDAC escapes early detection and resists treatment. Multiple combinations of genetic alterations are known to occur in PDAC including mutational activation of KRAS, inactivation of p16/CDKN2A and SMAD4 (DPC4 and dysregulation of PTEN/PI3K/AKT signaling. Through their interaction with WNT pathway, the downstream molecules of these pathways have been implicated in the promotion of epithelial-mesenchymal transition (EMT. Emerging evidence has demonstrated that cancer stem cells (CSCs, small populations of which have been identified in PDAC, and EMT-type cells play critical roles in drug resistance, invasion and metastasis in pancreatic cancer. EMT may be histologically represented by the presence of tumor budding which is described as the occurrence of single tumor cells or small clusters (<5 of dedifferentiated cells at the invasive front of gastrointestinal (including colorectal, oesophageal, gastric and ampullary carcinomas and is linked to poor prognosis. Tumor budding has recently been shown to occur frequently in PDAC and to be associated with adverse clinicopathological features and decreased disease-free and overall survival. The aim of this review is to present a short overview on the morphological and molecular aspects that underline the relationship between tumor budding cells, CSCs and EMT-type cells in PDAC.

  9. The increase of microRNA-21 during lung fibrosis and its contribution to epithelial-mesenchymal transition in pulmonary epithelial cells.

    Science.gov (United States)

    Yamada, Mitsuhiro; Kubo, Hiroshi; Ota, Chiharu; Takahashi, Toru; Tando, Yukiko; Suzuki, Takaya; Fujino, Naoya; Makiguchi, Tomonori; Takagi, Kiyoshi; Suzuki, Takashi; Ichinose, Masakazu

    2013-09-24

    The excess and persistent accumulation of fibroblasts due to aberrant tissue repair results in fibrotic diseases such as idiopathic pulmonary fibrosis. Recent reports have revealed significant changes in microRNAs during idiopathic pulmonary fibrosis and evidence in support of a role for microRNAs in myofibroblast differentiation and the epithelial-mesenchymal transition in the context of fibrosis. It has been reported that microRNA-21 is up-regulated in myofibroblasts during fibrosis and promotes transforming growth factor-beta signaling by inhibiting Smad7. However, expression changes in microRNA-21 and the role of microRNA-21 in epithelial-mesenchymal transition during lung fibrosis have not yet been defined. Lungs from saline- or bleomycin-treated C57BL/6 J mice and lung specimens from patients with idiopathic pulmonary fibrosis were analyzed. Enzymatic digestions were performed to isolate single lung cells. Lung epithelial cells were isolated by flow cytometric cell sorting. The expression of microRNA-21 was analyzed using both quantitative PCR and in situ hybridization. To induce epithelial-mesenchymal transition in culture, isolated mouse lung alveolar type II cells were cultured on fibronectin-coated chamber slides in the presence of transforming growth factor-β, thus generating conditions that enhance epithelial-mesenchymal transition. To investigate the role of microRNA-21 in epithelial-mesenchymal transition, we transfected cells with a microRNA-21 inhibitor. Total RNA was isolated from the freshly isolated and cultured cells. MicroRNA-21, as well as mRNAs of genes that are markers of alveolar epithelial or mesenchymal cell differentiation, were quantified using quantitative PCR. The lung epithelial cells isolated from the bleomycin-induced lung fibrosis model system had decreased expression of epithelial marker genes, whereas the expression of mesenchymal marker genes was increased. MicroRNA-21 was significantly upregulated in isolated lung epithelial

  10. An Analysis of Challenges Faced by Students Learning in Virtual and Open Distance Learning System: A Case of Bindura University of Science Education (BUSE)

    Science.gov (United States)

    Dodo, Obediah; Makwerere, David; Parwada, Matavire; Parwada, Cosmas

    2013-01-01

    After realizing that the traditional modes of tuition in Zimbabwe's andragogy had either gone obsolete or over-crowded, BUSE ventured into a "virtualised" model of open and distance learning as a way of out-doing other competing universities. However, as the programme was rolled out, there came a myriad of challenges affecting the…

  11. Cysteine cathepsins B and X promote epithelial-mesenchymal transition of tumor cells.

    Science.gov (United States)

    Mitrović, Ana; Pečar Fonović, Urša; Kos, Janko

    2017-09-01

    Cathepsins B and X are lysosomal cysteine carboxypeptidases suggested as having a redundant role in cancer. They are involved in a number of processes leading to tumor progression but their role in the epithelial-mesenchymal transition (EMT) remains unknown. We have investigated the contribution of both cathepsins B and X in EMT using tumor cell lines differing in their expression of epithelial and mesenchymal markers and cell morphology. Higher levels of both cathepsins are shown to promote EMT and are associated with the mesenchymal-like cell phenotype. Moreover, simultaneous knockdown of the two peptidases triggers a reverse, mesenchymal to epithelial transition. Of the two cathepsins, cathepsin B appears to be the stronger promotor of EMT. Furthermore, we evaluated the involvement of cathepsin B and X in the transforming growth factor-β1 (TGF-β1) signaling pathway, one of the key signaling mechanisms triggering EMT in cancer. In MCF-7 cells the expression of cathepsin B was shown to depend on their activation with TGF-β1 while, for cathepsin X, a TGF-β1 independent mechanism of induction during EMT is indicated. EMT is thus shown to be another mechanism linking cathepsins B and X with tumor progression. With silencing of their expression or inhibition of enzymatic activity, the tumor cells could be reverted to less aggressive epithelial-like phenotype. Copyright © 2017 Elsevier GmbH. All rights reserved.

  12. The Business Case for Fuel Cells: Delivering Sustainable Value

    Energy Technology Data Exchange (ETDEWEB)

    Curtin, Sandra [Fuel Cell and Hydrogen Energy Association (FCHEA), Washington, DC (United States); Gangi, Jennifer [Fuel Cell and Hydrogen Energy Association (FCHEA), Washington, DC (United States)

    2017-09-11

    This report, written and compiled by Argonne National Laboratory and the Fuel Cell and Hydrogen Energy Association with support from the Fuel Cell Technologies Office, provides an overview of private sector fuel cell installations at U.S. businesses as of December 31, 2016. Over the past few decades, hundreds of thousands of fuel cells have been installed around the world, for primary or backup power, as well as in various other applications including portable and emergency backup power. Fuel cells have also been deployed in other applications such as heat and electricity for homes and apartments, material handling, passenger vehicles, buses, and remote, off-grid sites.

  13. The nature and dynamic of phase transitions during cooling - warming of garlic cell sap

    Directory of Open Access Journals (Sweden)

    А. Т. Ходько

    2015-04-01

    Full Text Available To identify the type of phase transition during cooling-warming in the garlic cell sap by cryomicroscopy of samples in transmitted light phenomenon of critical opalescence was recorded. Critical state is peculiar only for phase transitions between the isotropic mediums. This fact gives grounds to include phase transition in the investigated system to liquid-liquid type, which proceeds according to spinodal mechanism and nucleus growth mechanism. During rapid cooling cracking of the samples due to high internal stresses (in contrast to the slow cooling was observed. After the phase transition during cooling rouglydispersed system – highly concentrated emulsion-gel was formed. Signs of crystallization in the system under the studied conditions were not found.

  14. Real life testing of a Hybrid PEM Fuel Cell Bus

    Science.gov (United States)

    Folkesson, Anders; Andersson, Christian; Alvfors, Per; Alaküla, Mats; Overgaard, Lars

    Fuel cells produce low quantities of local emissions, if any, and are therefore one of the most promising alternatives to internal combustion engines as the main power source in future vehicles. It is likely that urban buses will be among the first commercial applications for fuel cells in vehicles. This is due to the fact that urban buses are highly visible for the public, they contribute significantly to air pollution in urban areas, they have small limitations in weight and volume and fuelling is handled via a centralised infrastructure. Results and experiences from real life measurements of energy flows in a Scania Hybrid PEM Fuel Cell Concept Bus are presented in this paper. The tests consist of measurements during several standard duty cycles. The efficiency of the fuel cell system and of the complete vehicle are presented and discussed. The net efficiency of the fuel cell system was approximately 40% and the fuel consumption of the concept bus is between 42 and 48% lower compared to a standard Scania bus. Energy recovery by regenerative braking saves up 28% energy. Bus subsystems such as the pneumatic system for door opening, suspension and brakes, the hydraulic power steering, the 24 V grid, the water pump and the cooling fans consume approximately 7% of the energy in the fuel input or 17% of the net power output from the fuel cell system. The bus was built by a number of companies in a project partly financed by the European Commission's Joule programme. The comprehensive testing is partly financed by the Swedish programme "Den Gröna Bilen" (The Green Car). A 50 kW el fuel cell system is the power source and a high voltage battery pack works as an energy buffer and power booster. The fuel, compressed hydrogen, is stored in two high-pressure stainless steel vessels mounted on the roof of the bus. The bus has a series hybrid electric driveline with wheel hub motors with a maximum power of 100 kW. Hybrid Fuel Cell Buses have a big potential, but there are

  15. Transitional-2 B cells acquire regulatory function during tolerance induction and contribute to allograft survival.

    Science.gov (United States)

    Moreau, Aurélie; Blair, Paul A; Chai, Jian-Guo; Ratnasothy, Kulachelvy; Stolarczyk, Emilie; Alhabbab, Rowa; Rackham, Chloe L; Jones, Peter M; Smyth, Lesley; Elgueta, Raul; Howard, Jane K; Lechler, Robert I; Lombardi, Giovanna

    2015-03-01

    In humans, tolerance to renal transplants has been associated with alterations in B-cell gene transcription and maintenance of the numbers of circulating transitional B cells. Here, we use a mouse model of transplantation tolerance to investigate the contribution of B cells to allograft survival. We demonstrate that transfer of B cells from mice rendered tolerant to MHC class I mismatched skin grafts can prolong graft survival in a dose-dependent and antigen-specific manner to a degree similar to that afforded by graft-specific regulatory T (Treg) cells. Tolerance in this model was associated with an increase in transitional-2 (T2) B cells. Only T2 B cells from tolerized mice, not naïve T2 nor alloantigen experienced T2, were capable of prolonging skin allograft survival, and suppressing T-cell activation. Tolerized T2 B cells expressed lower levels of CD86, increased TIM-1, and demonstrated a preferential survival in vivo. Furthermore, we demonstrate a synergistic effect between tolerized B cells and graft-specific Treg cells. IL-10 production by T2 B cells did not contribute to tolerance, as shown by transfer of B cells from IL-10(-/-) mice. These results suggest that T2 B cells in tolerant patients may include a population of regulatory B cells that directly inhibit graft rejection. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Improved Accelerated Stress Tests Based on Fuel Cell Vehicle Data

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, Timothy [Research Engineer; Motupally, Sathya [Research Engineer

    2012-06-01

    UTC will led a top-tier team of industry and national laboratory participants to update and improve DOE’s Accelerated Stress Tests (AST’s) for hydrogen fuel cells. This in-depth investigation will focused on critical fuel cell components (e.g. membrane electrode assemblies - MEA) whose durability represented barriers for widespread commercialization of hydrogen fuel cell technology. UTC had access to MEA materials that had accrued significant load time under real-world conditions in PureMotion® 120 power plant used in transit buses. These materials are referred to as end-of-life (EOL) components in the rest of this document. Advanced characterization techniques were used to evaluate degradation mode progress using these critical cell components extracted from both bus power plants and corresponding materials tested using the DOE AST’s. These techniques were applied to samples at beginning-of-life (BOL) to serve as a baseline. These comparisons advised the progress of the various failure modes that these critical components were subjected to, such as membrane degradation, catalyst support corrosion, platinum group metal dissolution, and others. Gaps in the existing ASTs predicted the degradation observed in the field in terms of these modes were outlined. Using the gaps, new AST’s were recommended and tested to better reflect the degradation modes seen in field operation. Also, BOL components were degraded in a test vehicle at UTC designed to accelerate the bus field operation.

  17. Effects of Photovoltaic and Fuel Cell Hybrid System on Distribution Network Considering the Voltage Limits

    Directory of Open Access Journals (Sweden)

    ABYANEH, H. A.

    2010-11-01

    Full Text Available Development of distribution network and power consumption growth, increase voltage drop on the line impedance and therefore voltage drop in system buses. In some cases consumption is so high that voltage in some buses exceed from standard. In this paper, effect of the fuel cell and photovoltaic hybrid system on distribution network for solving expressed problem is studied. For determining the capacity of each distributed generation source, voltage limitation on the bus voltages under different conditions is considered. Simulation is done by using DIgSILENT software on the part of the 20 kV real life Sirjan distribution system. In this article, optimum location with regard to system and environmental conditions are studied in two different viewpoints.

  18. Zeatin is indispensable for the G2-M transition in tobacco BY-2 cells.

    Science.gov (United States)

    Laureys, F; Dewitte, W; Witters, E; Van Montagu, M; Inzé, D; Van Onckelen, H

    1998-04-10

    The importance of N6-isoprenoid cytokinins in the G2-M transition of Nicotiana tabacum BY-2 cells was investigated. Both cytokinin biosynthesis and entry in mitosis were partially blocked by application at early or late G2 of lovastatin (10 microM), an inhibitor of mevalonic acid synthesis. LC-MS/MS quantification of endogenous cytokinins proved that lovastatin affects cytokinin biosynthesis by inhibiting HMG-CoA reductase. Out of eight different aminopurines and a synthetic auxin tested for their ability to override lovastatin inhibition of mitosis, only zeatin was active. Our data point to a key role for a well-defined cytokinin (here, zeatin) in the G2-M transition of tobacco BY-2 cells.

  19. Estimation of transition doses for human glioblastoma, neuroblastoma and prostate cell lines using the linear-quadratic formalism

    Directory of Open Access Journals (Sweden)

    John Akudugu

    2015-09-01

    Full Text Available Purpose: The introduction of stereotactic radiotherapy has raised concerns regarding the use of the linear-quadratic (LQ model for predicting radiation response for large fractional doses. To partly address this issue, a transition dose D* below which the LQ model retains its predictive strength has been proposed. Estimates of D* which depends on the a, β, and D0 parameters are much lower than fractional doses typically encountered in stereotactic radiotherapy. D0, often referred to as the final slope of the cell survival curve, is thought to be constant. In vitro cell survival curves generally extend over the first few logs of cell killing, where D0-values derived from the multi-target formalism may be overestimated and can lead to low transition doses. Methods:  D0-values were calculated from first principles for each decade of cell killing, using experimentally-determined a and β parameters for 17 human glioblastoma, neuroblastoma, and prostate cell lines, and corresponding transition doses were derived.Results: D0 was found to decrease exponentially with cell killing. Using D0-values at cell surviving fractions of the order of 10-10 yielded transition doses ~3-fold higher than those obtained from D0-values obtained from conventional approaches. D* was found to increase from 7.84 ± 0.56, 8.91 ± 1.20, and 6.55 ± 0.91 Gy to 26.84 ± 2.83, 23.95 ± 2.03, and 22.49 ± 2.31 Gy for the glioblastoma, neuroblastoma, and prostate cell lines, respectively. Conclusion: These findings suggest that the linear-quadratic formalism might be valid for estimating the effect of stereotactic radiotherapy with fractional doses in excess of 20 Gy.

  20. Phase Transition Control for High-Performance Blade-Coated Perovskite Solar Cells

    KAUST Repository

    Li, Jianbo

    2018-05-07

    Summary Here, we have identified that the key issue for rational transitioning from spin-coating to blade-coating processes of perovskite films arises from whether intermediate phases participate in the phase transition. In situ characterizations were carried out to provide a comprehensive picture of structural evolution and crystal growth mechanisms. These findings present opportunities for designing an effective process for blade-coating perovskite film: a large-grained dense perovskite film with high crystal quality and photophysical properties can be obtained only via direct crystallization for both spin-coating and blade-coating processes. As a result, the blade-coated MAPbI3 films deliver excellent charge-collection efficiency at both short circuit and open circuit, and photovoltaic properties with efficiencies of 18.74% (0.09 cm2) and 17.06% (1 cm2) in planar solar cells. The significant advances in understanding how the phase transition links spin-coating and blade-coating processes should provide a path toward high-performance printed perovskite devices.

  1. Paeoniflorin prevents hypoxia-induced epithelial–mesenchymal transition in human breast cancer cells

    Directory of Open Access Journals (Sweden)

    Zhou Z

    2016-04-01

    Full Text Available Zhenyu Zhou,1,* Shunchang Wang,1,* Caijuan Song,2 Zhuang Hu11Department of Thyroid and Breast, Huaihe Hospital, Henan University, Kaifeng, 2Department of Immunization Program, Zhengzhou Center for Disease Control and Prevention, Zhengzhou, People’s Republic of China*These authors contributed equally to this workAbstract: Paeoniflorin (PF is a monoterpene glycoside extracted from the root of Paeonia lactiflora Pall. Previous studies have demonstrated that PF inhibits the growth, invasion, and metastasis of tumors in vivo and in vitro. However, the effect of PF on hypoxia-induced epithelial–mesenchymal transition (EMT in breast cancer cells remains unknown. Therefore, the objective of this study was to investigate the effect of PF on hypoxia-induced EMT in breast cancer cells, as well as characterize the underlying mechanism. The results presented in this study demonstrate that PF blocks the migration and invasion of breast cancer cells by repressing EMT under hypoxic conditions. PF also significantly attenuated the hypoxia-induced increase in HIF-1α level. Furthermore, PF prevented hypoxia-induced expression of phosphorylated PI3K and Akt in MDA-MB-231 cells. In conclusion, PF prevented hypoxia-induced EMT in breast cancer cells by inhibiting HIF-1α expression via modulation of PI3K/Akt signaling pathway. This finding provides evidence that PF can serve as a therapeutic agent for the treatment of breast cancer.Keywords: paeoniflorin, breast cancer, hypoxia, epithelial–mesenchymal transition, PI3K/Akt signaling pathway

  2. Luteolin inhibits the colon cancer HT-29 cell proliferation, migration and epithelial-mesenchymal transition: an experimental study

    Directory of Open Access Journals (Sweden)

    Xin Meng

    2017-11-01

    Full Text Available Objective: To study the regulating effect of luteolin on colon cancer HT-29 cell proliferation, migration and epithelial-mesenchymal transition. Methods: Colon cancer HT-29 cells were cultured and randomly divided into two groups, control group were treated with serum-free medium without drugs and LUT group were treated with serum-free medium containing luteolin. After 24 h of treatment, cells were collected to extract RNA, and then fluorescent quantitative PCR method was used to determine the mRNA expression of proliferation genes, migration genes and epithelial-mesenchymal transition genes. Results: After 24 h of luteolin treatment, Lrig1, TSPYL5, Bim, SOX15 and DLC1 mRNA expression in LUT group were significantly higher than those in control group while RPS15a, Bad, TRPV5, TRPV6, PLD2, IBP, SphK1, FAK, Vimentin and N-cadherin mRNA expression were significantly lower than those in control group. Conclusion: Luteolin has inhibiting effect on colon cancer HT-29 cell proliferation, migration and epithelial-mesenchymal transition.

  3. Cancer Stem Cells and Epithelial-to-Mesenchymal Transition (EMT)-Phenotypic Cells: Are They Cousins or Twins?

    International Nuclear Information System (INIS)

    Kong, Dejuan; Li, Yiwei; Wang, Zhiwei; Sarkar, Fazlul H.

    2011-01-01

    Cancer stem cells (CSCs) are cells within a tumor that possess the capacity to self-renew and maintain tumor-initiating capacity through differentiation into the heterogeneous lineages of cancer cells that comprise the whole tumor. These tumor-initiating cells could provide a resource for cells that cause tumor recurrence after therapy. Although the cell origin of CSCs remains to be fully elucidated, mounting evidence has demonstrated that Epithelial-to-Mesenchymal Transition (EMT), induced by different factors, is associated with tumor aggressiveness and metastasis and these cells share molecular characteristics with CSCs, and thus are often called cancer stem-like cells or tumor-initiating cells. The acquisition of an EMT phenotype is a critical process for switching early stage carcinomas into invasive malignancies, which is often associated with the loss of epithelial differentiation and gain of mesenchymal phenotype. Recent studies have demonstrated that EMT plays a critical role not only in tumor metastasis but also in tumor recurrence and that it is tightly linked with the biology of cancer stem-like cells or cancer-initiating cells. Here we will succinctly summarize the state-of-our-knowledge regarding the molecular similarities between cancer stem-like cells or CSCs and EMT-phenotypic cells that are associated with tumor aggressiveness focusing on solid tumors

  4. Cancer Stem Cells and Epithelial-to-Mesenchymal Transition (EMT-Phenotypic Cells: Are They Cousins or Twins?

    Directory of Open Access Journals (Sweden)

    Fazlul H. Sarkar

    2011-02-01

    Full Text Available Cancer stem cells (CSCs are cells within a tumor that possess the capacity to self-renew and maintain tumor-initiating capacity through differentiation into the heterogeneous lineages of cancer cells that comprise the whole tumor. These tumor-initiating cells could provide a resource for cells that cause tumor recurrence after therapy. Although the cell origin of CSCs remains to be fully elucidated, mounting evidence has demonstrated that Epithelial-to-Mesenchymal Transition (EMT, induced by different factors, is associated with tumor aggressiveness and metastasis and these cells share molecular characteristics with CSCs, and thus are often called cancer stem-like cells or tumor-initiating cells. The acquisition of an EMT phenotype is a critical process for switching early stage carcinomas into invasive malignancies, which is often associated with the loss of epithelial differentiation and gain of mesenchymal phenotype. Recent studies have demonstrated that EMT plays a critical role not only in tumor metastasis but also in tumor recurrence and that it is tightly linked with the biology of cancer stem-like cells or cancer-initiating cells. Here we will succinctly summarize the state-of-our-knowledge regarding the molecular similarities between cancer stem-like cells or CSCs and EMT-phenotypic cells that are associated with tumor aggressiveness focusing on solid tumors.

  5. CD4 T Cell Epitope Specificity and Cytokine Potential Are Preserved as Cells Transition from the Lung Vasculature to Lung Tissue following Influenza Virus Infection.

    Science.gov (United States)

    DiPiazza, Anthony; Laniewski, Nathan; Rattan, Ajitanuj; Topham, David J; Miller, Jim; Sant, Andrea J

    2018-07-01

    Pulmonary CD4 T cells are critical in respiratory virus control, both by delivering direct effector function and through coordinating responses of other immune cells. Recent studies have shown that following influenza virus infection, virus-specific CD4 T cells are partitioned between pulmonary vasculature and lung tissue. However, very little is known about the peptide specificity or functional differences of CD4 T cells within these two compartments. Using a mouse model of influenza virus infection in conjunction with intravascular labeling in vivo , the cell surface phenotype, epitope specificity, and functional potential of the endogenous polyclonal CD4 T cell response was examined by tracking nine independent CD4 T cell epitope specificities. These studies revealed that tissue-localized CD4 cells were globally distinct from vascular cells in expression of markers associated with transendothelial migration, residency, and micropositioning. Despite these differences, there was little evidence for remodeling of the viral epitope specificity or cytokine potential as cells transition from vasculature to the highly inflamed lung tissue. Our studies also distinguished cells in the pulmonary vasculature from peripheral circulating CD4 T cells, providing support for the concept that the pulmonary vasculature does not simply reflect circulating cells that are trapped within the narrow confines of capillary vessels but rather is enriched in transitional cells primed in the draining lymph node that have specialized potential to enter the lung tissue. IMPORTANCE CD4 T cells convey a multitude of functions in immunity to influenza, including those delivered in the lymph node and others conveyed by CD4 T cells that leave the lymph node, enter the blood, and extravasate into the lung tissue. Here, we show that the transition of recently primed CD4 cells detected in the lung vasculature undergo profound changes in expression of markers associated with tissue localization as

  6. Transitional cell carcinoma involving the ductus deferens in a dog.

    Science.gov (United States)

    Guerin, Vincent J; 't Hooft, Krista W Visser; L'Eplattenier, Henry F; Petite, Audrey F

    2012-02-15

    A 12-year-old neutered male Springer Spaniel was referred with a 1-year history of recurring urinary tract infections. Repeated treatment with appropriate antimicrobials selected on the basis of bacterial culture and antimicrobial susceptibility results would result in clinical improvement, but recurrence of clinical signs was observed within days after discontinuation of treatment. Ultrasound examination revealed a tubular, fluid-filled structure dorsal to the bladder that extended from the midlevel of the bladder to the cranial pole of the prostate. Mineralized foci within a heterogeneous prostatic parenchyma were also noted. Dilation of the right ductus deferens (DD) was observed during exploratory laparotomy. Both DD were surgically removed, and the prostate was biopsied. The histopathological diagnosis was transitional cell carcinoma involving the right DD and the prostate. The dog was treated with meloxicam (0.1 mg/kg [0.05 mg/lb], p.o., q 24 h) for 9 months after diagnosis before being euthanized. Because the normal DD is rarely visualized during abdominal ultrasonography in dogs, identification of a tubular, fluid-filled structure dorsal to the bladder may indicate an abnormal DD. Transitional cell carcinoma of the DD should be included in the differential diagnoses of affected patients examined for clinical signs involving the urinary tract.

  7. Regulation of mitosis-meiosis transition by the ubiquitin ligase β-TrCP in male germ cells.

    Science.gov (United States)

    Nakagawa, Tadashi; Zhang, Teng; Kushi, Ryo; Nakano, Seiji; Endo, Takahiro; Nakagawa, Makiko; Yanagihara, Noriko; Zarkower, David; Nakayama, Keiko

    2017-11-15

    The mitosis-meiosis transition is essential for spermatogenesis. Specific and timely downregulation of the transcription factor DMRT1, and consequent induction of Stra8 expression, is required for this process in mammals, but the molecular mechanism has remained unclear. Here, we show that β-TrCP, the substrate recognition component of an E3 ubiquitin ligase complex, targets DMRT1 for degradation and thereby controls the mitosis-meiosis transition in mouse male germ cells. Conditional inactivation of β-TrCP2 in male germ cells of β-TrCP1 knockout mice resulted in sterility due to a lack of mature sperm. The β-TrCP-deficient male germ cells did not enter meiosis, but instead underwent apoptosis. The induction of Stra8 expression was also attenuated in association with the accumulation of DMRT1 at the Stra8 promoter in β-TrCP-deficient testes. DMRT1 contains a consensus β-TrCP degron sequence that was found to bind β-TrCP. Overexpression of β-TrCP induced the ubiquitylation and degradation of DMRT1. Heterozygous deletion of Dmrt1 in β-TrCP-deficient spermatogonia increased meiotic cells with a concomitant reduction of apoptosis. Collectively, our data indicate that β-TrCP regulates the transition from mitosis to meiosis in male germ cells by targeting DMRT1 for degradation. © 2017. Published by The Company of Biologists Ltd.

  8. Effect of Twist, Snail and YB-1 gene expression in cervical cancer tissue on cell invasion and epithelial-mesenchymal transition

    Directory of Open Access Journals (Sweden)

    Xin-Qin Kang1

    2017-05-01

    Full Text Available Objective: To study the effect of Twist, Snail and YB-1 gene expression in cervical cancer tissue on cell invasion and epithelial-mesenchymal transition. Methods: Cervical cancer tissue samples and tissue samples adjacent to carcinoma were collected from 138 patients with radical operation for cervical cancer, fluorescence quantitative PCR method was used to detect the mRNA expression of Twist, Snail and YB-1 genes, cell invasion-related genes and epithelial-mesenchymal transition marker genes, the Pearson test was used to analyze the correlation of Twist, Snail and YB-1 gene mRNA expression in cervical cancer tissue with cell invasion and epithelial-mesenchymal transition. Results: Twist, Snail and YB-1 gene mRNA expression in cervical cancer tissue were higher than those in tissue adjacent to carcinoma, the invasion genes STAT3, YAP1, TUG1, FoxM1 and Rab11 mRNA expression were higher than those in tissue adjacent to carcinoma, and the epithelial-mesenchymal transition markers E-cadherin and β-catenin gene mRNA expression were lower than those in tissue adjacent to carcinoma while vimentin gene mRNA expression was higher than that in tissue adjacent to carcinoma. Pearson test showed that Twist, Snail and YB-1 gene mRNA expression in cervical cancer tissue were directly correlated with cell invasion and epithelial-mesenchymal transition. Conclusion: Twist, Snail and YB-1 genes are highly expressed in cervical cancer tissue, and their abnormal expression directly leads to the increased tumor cell invasion activity and the aggravated epithelial-mesenchymal transition.

  9. OSU TOMF Program Site Selection and Preliminary Concept Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Spadling, Steve [Oklahoma State Univ., Stillwater, OK (United States)

    2012-05-10

    The purpose of this report is to confirm the programmatic requirements for the new facilities, identify the most appropriate project site, and develop preliminary site and building concepts that successfully address the overall project goals and site issues. These new facilities will be designed to accommodate the staff, drivers and maintenance requirements for the future mixed fleet of passenger vehicles, Transit Style Buses and School Buses.

  10. Investigation of microwave transitions and nonlinear magneto-optical rotation in anti-relaxation-coated cells

    International Nuclear Information System (INIS)

    Budker, D.; Hollberg, L.; Kimball, D.F.; Kitching, J.; Pustclny, S.; Robinson, H.G.; Yashchuk, V.V.

    2004-01-01

    Using laser optical pumping, widths and frequency shifts are determined for microwave transitions between the components of the ground-state hyperfine structure for 85 Rb and 87 Rb atoms contained in vapor cells with alkane anti-relaxation coatings. The results are compared with data on Zeeman relaxation obtained in nonlinear magneto-optical rotation (NMOR) experiments, a comparison important for quantitative understanding of spin-relaxation mechanisms in coated cells. By comparing cells manufactured over a forty-year period we demonstrate the long-term stability of coated cells, which may be useful for atomic clocks and magnetometers

  11. Investigation of microwave transitions and nonlinear magneto-optical rotation in anti-relaxation-coated cells

    International Nuclear Information System (INIS)

    Budker, Dmitry; Hollberg, Leo; Kimball, Derek F.; Kitching, J.; Pustelny, Szymon; Yashchuk, Valeriy V.

    2004-01-01

    Using laser optical pumping, widths and frequency shifts are determined for microwave transitions between ground-state hyperfine components of 85 Rb and 87 Rb atoms contained in vapor cells with alkane anti-relaxation coatings. The results are compared with data on Zeeman relaxation obtained in nonlinear magneto-optical rotation (NMOR) experiments, a comparison important for quantitative understanding of spin-relaxation mechanisms in coated cells. By comparing cells manufactured over a forty-year period we demonstrate the long-term stability of coated cells, an important property for atomic clocks and magnetometers

  12. Electric bus fleet size and mix problem with optimization of charging infrastructure

    DEFF Research Database (Denmark)

    Rogge, Matthias; van der Hurk, Evelien; Larsen, Allan

    2018-01-01

    Battery electric buses are seen as a well-suited technology for the electrification of road-based public transport. However, the transition process from conventional diesel to electric buses faces major hurdles caused by range limitations and required charging times of battery buses. This work...... addresses these constraints and provides a methodology for the cost-optimized planning of depot charging battery bus fleets and their corresponding charging infrastructure. The defined problem covers the scheduling of battery buses, the fleet composition, and the optimization of charging infrastructure...... in a joint process. Vehicle schedule adjustments are monetized and evaluated together with the investment and operational costs of the bus system. The resulting total cost of ownership enables a comparison of technical alternatives on a system level, which makes this approach especially promising...

  13. Proteinase-activated receptor 4 stimulation-induced epithelial-mesenchymal transition in alveolar epithelial cells

    Directory of Open Access Journals (Sweden)

    Araki Hiromasa

    2007-04-01

    Full Text Available Abstract Background Proteinase-activated receptors (PARs; PAR1–4 that can be activated by serine proteinases such as thrombin and neutrophil catepsin G are known to contribute to the pathogenesis of various pulmonary diseases including fibrosis. Among these PARs, especially PAR4, a newly identified subtype, is highly expressed in the lung. Here, we examined whether PAR4 stimulation plays a role in the formation of fibrotic response in the lung, through alveolar epithelial-mesenchymal transition (EMT which contributes to the increase in myofibroblast population. Methods EMT was assessed by measuring the changes in each specific cell markers, E-cadherin for epithelial cell, α-smooth muscle actin (α-SMA for myofibroblast, using primary cultured mouse alveolar epithelial cells and human lung carcinoma-derived alveolar epithelial cell line (A549 cells. Results Stimulation of PAR with thrombin (1 U/ml or a synthetic PAR4 agonist peptide (AYPGKF-NH2, 100 μM for 72 h induced morphological changes from cobblestone-like structure to elongated shape in primary cultured alveolar epithelial cells and A549 cells. In immunocytochemical analyses of these cells, such PAR4 stimulation decreased E-cadherin-like immunoreactivity and increased α-SMA-like immunoreactivity, as observed with a typical EMT-inducer, tumor growth factor-β (TGF-β. Western blot analyses of PAR4-stimulated A549 cells also showed similar changes in expression of these EMT-related marker proteins. Such PAR4-mediated changes were attenuated by inhibitors of epidermal growth factor receptor (EGFR kinase and Src. PAR4-mediated morphological changes in primary cultured alveolar epithelial cells were reduced in the presence of these inhibitors. PAR4 stimulation increased tyrosine phosphorylated EGFR or tyrosine phosphorylated Src level in A549 cells, and the former response being inhibited by Src inhibitor. Conclusion PAR4 stimulation of alveolar epithelial cells induced epithelial

  14. Reliability improvement of potential transformer and secondary circuit of 6 kV 1E-class buses in Qinshan nuclear power plant

    International Nuclear Information System (INIS)

    Qian Houjun

    2014-01-01

    There are design defects in potential transformer (PT) and secondary circuit of 6 kV 1E-class buses in Qinshan Nuclear Power Plant Nuclear Island. During the operating period, there happened several serious operational events (loss of power) caused by PT resonance. The essay analyses the defects of original design, and put forward corresponding modification measures, which have been carried out by two steps between 2009 and 2010, and after the modification the same problems have not happened again. (author)

  15. HGFA Is an Injury-Regulated Systemic Factor that Induces the Transition of Stem Cells into GAlert

    Directory of Open Access Journals (Sweden)

    Joseph T. Rodgers

    2017-04-01

    Full Text Available Summary: The activation of quiescent stem cells into the cell cycle is a key step in initiating the process of tissue repair. We recently reported that quiescent stem cells can transition into GAlert, a cellular state in which they have an increased functional ability to activate and participate in tissue repair. However, the precise molecular signals that induce GAlert in stem cells have remained elusive. Here, we show that the injury-induced regulation of hepatocyte growth factor (HGF proteolytic processing via the systemic protease, hepatocyte growth factor activator (HGFA, stimulates GAlert in skeletal muscle stem cells (MuSCs and fibro-adipogenic progenitors (FAPs. We demonstrate that administering active HGFA to animals is sufficient to induce GAlert in stem cells throughout the body and to significantly accelerate the processes of stem cell activation and tissue repair. Our data suggest that factors that induce GAlert will have broad therapeutic applications for regenerative medicine and wound healing. : Rodgers et al. show that HGFA is a systemic protease that is activated by tissue injury and relays a signal to stem cells in non-injured tissues that induces their transition into a primed, “GAlert” state in which they possess an enhanced potential to activate and repair tissue damage. Keywords: satellite cells, muscle stem cells, fibro-adipogenic progenitors, HGFA, HGF, mTORC1, cMet, stem cell quiescence, stem cell activation, GAlert

  16. Characterization of Transition Metal Oxide/Silicon Heterojunctions for Solar Cell Applications

    Directory of Open Access Journals (Sweden)

    Luis G. Gerling

    2015-10-01

    Full Text Available During the last decade, transition metal oxides have been actively investigated as hole- and electron-selective materials in organic electronics due to their low-cost processing. In this study, four transition metal oxides (V2O5, MoO3, WO3, and ReO3 with high work functions (>5 eV were thermally evaporated as front p-type contacts in planar n-type crystalline silicon heterojunction solar cells. The concentration of oxygen vacancies in MoO3−x was found to be dependent on film thickness and redox conditions, as determined by X-ray Photoelectron Spectroscopy. Transfer length method measurements of oxide films deposited on glass yielded high sheet resistances (~109 Ω/sq, although lower values (~104 Ω/sq were measured for oxides deposited on silicon, indicating the presence of an inversion (hole rich layer. Of the four oxide/silicon solar cells, ReO3 was found to be unstable upon air exposure, while V2O5 achieved the highest open-circuit voltage (593 mV and conversion efficiency (12.7%, followed by MoO3 (581 mV, 12.6% and WO3 (570 mV, 11.8%. A short-circuit current gain of ~0.5 mA/cm2 was obtained when compared to a reference amorphous silicon contact, as expected from a wider energy bandgap. Overall, these results support the viability of a simplified solar cell design, processed at low temperature and without dopants.

  17. Change in cell shape is required for matrix metalloproteinase-induced epithelial-mesenchymal transition of mammary epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Celeste M.; Khauv, Davitte; Bissell, Mina J.; Radisky, Derek C.

    2008-06-26

    Cell morphology dictates response to a wide variety of stimuli, controlling cell metabolism, differentiation, proliferation, and death. Epithelial-mesenchymal transition (EMT) is a developmental process in which epithelial cells acquire migratory characteristics, and in the process convert from a 'cuboidal' epithelial structure into an elongated mesenchymal shape. We had shown previously that matrix metalloproteinase-3 (MMP3) can stimulate EMT of cultured mouse mammary epithelial cells through a process that involves increased expression of Rac1b, a protein that stimulates alterations in cytoskeletal structure. We show here that cells treated with MMP-3 or induced to express Rac1b spread to cover a larger surface, and that this induction of cell spreading is a requirement of MMP-3/Rac1b-induced EMT. We find that limiting cell spreading, either by increasing cell density or by culturing cells on precisely defined micropatterned substrata, blocks expression of characteristic markers of EMT in cells treated with MMP-3. These effects are not caused by general disruptions in cell signaling pathways, as TGF-{beta}-induced EMT is not affected by similar limitations on cell spreading. Our data reveal a previously unanticipated cell shape-dependent mechanism that controls this key phenotypic alteration and provide insight into the distinct mechanisms activated by different EMT-inducing agents.

  18. Modeling transit bus fuel consumption on the basis of cycle properties.

    Science.gov (United States)

    Delgado, Oscar F; Clark, Nigel N; Thompson, Gregory J

    2011-04-01

    A method exists to predict heavy-duty vehicle fuel economy and emissions over an "unseen" cycle or during unseen on-road activity on the basis of fuel consumption and emissions data from measured chassis dynamometer test cycles and properties (statistical parameters) of those cycles. No regression is required for the method, which relies solely on the linear association of vehicle performance with cycle properties. This method has been advanced and examined using previously published heavy-duty truck data gathered using the West Virginia University heavy-duty chassis dynamometer with the trucks exercised over limited test cycles. In this study, data were available from a Washington Metropolitan Area Transit Authority emission testing program conducted in 2006. Chassis dynamometer data from two conventional diesel buses, two compressed natural gas buses, and one hybrid diesel bus were evaluated using an expanded driving cycle set of 16 or 17 different driving cycles. Cycle properties and vehicle fuel consumption measurements from three baseline cycles were selected to generate a linear model and then to predict unseen fuel consumption over the remaining 13 or 14 cycles. Average velocity, average positive acceleration, and number of stops per distance were found to be the desired cycle properties for use in the model. The methodology allowed for the prediction of fuel consumption with an average error of 8.5% from vehicles operating on a diverse set of chassis dynamometer cycles on the basis of relatively few experimental measurements. It was found that the data used for prediction should be acquired from a set that must include an idle cycle along with a relatively slow transient cycle and a relatively high speed cycle. The method was also applied to oxides of nitrogen prediction and was found to have less predictive capability than for fuel consumption with an average error of 20.4%.

  19. Isolated Meningeal Recurrence of Transitional Cell Carcinoma of the Bladder

    Directory of Open Access Journals (Sweden)

    Catherine Butchart

    2010-06-01

    Full Text Available Meningeal carcinomatosis occurs in 1–18% of patients with solid tumours, most commonly carcinomas of the breast and lung or melanomas. There are relatively few reports of meningeal carcinomatosis in transitional cell carcinoma of the bladder. Isolated meningeal recurrence is particularly uncommon, and we present an unusual case of this in a 58-year-old man. The case was further complicated by the somewhat atypical presentation with a confirmed ischaemic stroke. The patient died one month after presentation.

  20. Epithelial-Mesenchymal Transitions and the Expression of Twist in MCF-7/ADR,Human Multidrug-Resistant Breast Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    Fei Zhang; Yurong Shi; Lin Zhang; Bin Zhang; Xiyin Wei; Yi Yang; RUi Wang; Ruifang Niu

    2007-01-01

    OBJECTIVE To study the expression levels of Twist and epithelialmesenchymal transitions in multidrug-resistant MCF-7/ADR breast cancer cells,and to study the relationship between multidrug resistance (MDR) and metastatic potential of the cells.METHODS RT-PCR,immunohislochemical and Western blotting methods were used to examine the changes of expression levels of the transcription factor Twist.E-cadherin and N-cadherin in the MCF-7 breast cancer cell line and its multidrug-resistant variant.MCF-7/ADR.RESULTS In MCF-7 cells,the expression of E-cadherin can be detected,but there is no expression of Twisl or N-cadherin.In MCF-7/ADR cells,E-cadherin expression is lost.bul the expression of two other genes was significantly positive.CONCLUSION Epithelial-mesenchymal transitions induced by Twist,may have a relationship with enhanced invasion and metastatic potential during the development of multidrug-resistant MCF-7/ADR breast cancer cells.

  1. Quantitative cell polarity imaging defines leader-to-follower transitions during collective migration and the key role of microtubule-dependent adherens junction formation.

    Science.gov (United States)

    Revenu, Céline; Streichan, Sebastian; Donà, Erika; Lecaudey, Virginie; Hufnagel, Lars; Gilmour, Darren

    2014-03-01

    The directed migration of cell collectives drives the formation of complex organ systems. A characteristic feature of many migrating collectives is a 'tissue-scale' polarity, whereby 'leader' cells at the edge of the tissue guide trailing 'followers' that become assembled into polarised epithelial tissues en route. Here, we combine quantitative imaging and perturbation approaches to investigate epithelial cell state transitions during collective migration and organogenesis, using the zebrafish lateral line primordium as an in vivo model. A readout of three-dimensional cell polarity, based on centrosomal-nucleus axes, allows the transition from migrating leaders to assembled followers to be quantitatively resolved for the first time in vivo. Using live reporters and a novel fluorescent protein timer approach, we investigate changes in cell-cell adhesion underlying this transition by monitoring cadherin receptor localisation and stability. This reveals that while cadherin 2 is expressed across the entire tissue, functional apical junctions are first assembled in the transition zone and become progressively more stable across the leader-follower axis of the tissue. Perturbation experiments demonstrate that the formation of these apical adherens junctions requires dynamic microtubules. However, once stabilised, adherens junction maintenance is microtubule independent. Combined, these data identify a mechanism for regulating leader-to-follower transitions within migrating collectives, based on the relocation and stabilisation of cadherins, and reveal a key role for dynamic microtubules in this process.

  2. Fatigue-related crashes involving express buses in Malaysia: will the proposed policy of banning the early-hour operation reduce fatigue-related crashes and benefit overall road safety?

    Science.gov (United States)

    Mohamed, Norlen; Mohd-Yusoff, Mohammad-Fadhli; Othman, Ilhamah; Zulkipli, Zarir-Hafiz; Osman, Mohd Rasid; Voon, Wong Shaw

    2012-03-01

    Fatigue-related crashes have long been the topic of discussion and study worldwide. The relationship between fatigue-related crashes and time of day is well documented. In Malaysia, the possibility of banning express buses from operating during the early-hours of the morning has emerged as an important consideration for passenger safety. This paper highlights the findings of an impact assessment study. The study was conducted to determine all possible impacts prior to the government making any decision on the proposed banning. This study is an example of a simple and inexpensive approach that may influence future policy-making process. The impact assessment comprised two major steps. The first step involved profiling existing operation scenarios, gathering information on crashes involving public express buses and stakeholders' views. The second step involved a qualitative impact assessment analysis using all information gathered during the profiling stage to describe the possible impacts. Based on the assessment, the move to ban early-hour operations could possibly result in further negative impacts on the overall road safety agenda. These negative impacts may occur if the fundamental issues, such as driving and working hours, and the need for rest and sleep facilities for drivers, are not addressed. In addition, a safer and more accessible public transportation system as an alternative for those who choose to travel at night would be required. The proposed banning of early-hour operations is also not a feasible solution for sustainability of express bus operations in Malaysia, especially for those operating long journeys. The paper concludes by highlighting the need to design a more holistic approach for preventing fatigue-related crashes involving express buses in Malaysia. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Evaluation of Alternative Field Buses for Lighting ControlApplications

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Ed; Rubinstein, Francis

    2005-03-21

    The Subcontract Statement of Work consists of two major tasks. This report is the Final Report in fulfillment of the contract deliverable for Task 1. The purpose of Task 1 was to evaluate existing and emerging protocols and standards for interfacing sensors and controllers for communicating with integrated lighting control systems in commercial buildings. The detailed task description follows: Task 1. Evaluate alternative sensor/field buses. The objective of this task is to evaluate existing and emerging standards for interfacing sensors and controllers for communicating with integrated lighting control systems in commercial buildings. The protocols to be evaluated will include at least: (1) 1-Wire Net, (2) DALI, (3) MODBUS (or appropriate substitute such as EIB) and (4) ZigBee. The evaluation will include a comparative matrix for comparing the technical performance features of the different alternative systems. The performance features to be considered include: (1) directionality and network speed, (2) error control, (3) latency times, (4) allowable cable voltage drop, (5) topology, and (6) polarization. Specifically, Subcontractor will: (1) Analyze the proposed network architecture and identify potential problems that may require further research and specification. (2) Help identify and specify additional software and hardware components that may be required for the communications network to operate properly. (3) Identify areas of the architecture that can benefit from existing standards and technology and enumerate those standards and technologies. (4) Identify existing companies that may have relevant technology that can be applied to this research. (5) Help determine if new standards or technologies need to be developed.

  4. Analysis of production models and hydrogen supply for urban collective transportation buses: a case study at Foz do Iguacu; Analise de modelos de producao e abastecimento de hidrogenio para onibus de transporte coletivo urbano: estudo de caso em Foz do Iguacu

    Energy Technology Data Exchange (ETDEWEB)

    Riveros-Godoy, Gustavo [Universidade Nacional de Assuncao (Paraguay). Faculdade de Ciencias Quimicas]. E-mail: riveros@qui.una.py; Cavaliero, Carla; Peres, Ennio [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica

    2008-07-01

    Even though technical-economical barriers still exist for the development of an economy based in the hydrogen, these difficulties are opportunities for the appearance of new business of goods and services, energetic matrix diversification, focusing of researches activities, development and support to provide sustainability to the new economy. This study presents the technical-economical comparison of hydrogen production and supply models, using the so-called Spilled Turbinable Energy of the Itaipu Hydroelectric Power Plant and available for the transport sector. The substitution of the urban collective diesel bus fleet with fuel cell buses in Foz do Iguacu city was used as a case study in this work. (author)

  5. The TCP4 transcription factor of Arabidopsis blocks cell division in yeast at G1 → S transition

    International Nuclear Information System (INIS)

    Aggarwal, Pooja; Padmanabhan, Bhavna; Bhat, Abhay; Sarvepalli, Kavitha; Sadhale, Parag P.; Nath, Utpal

    2011-01-01

    Highlights: → TCP4 is a class II TCP transcription factor, that represses cell division in Arabidopsis. → TCP4 expression in yeast retards cell division by blocking G1 → S transition. → Genome-wide expression studies and Western analysis reveals stabilization of cell cycle inhibitor Sic1, as possible mechanism. -- Abstract: The TCP transcription factors control important aspects of plant development. Members of class I TCP proteins promote cell cycle by regulating genes directly involved in cell proliferation. In contrast, members of class II TCP proteins repress cell division. While it has been postulated that class II proteins induce differentiation signal, their exact role on cell cycle has not been studied. Here, we report that TCP4, a class II TCP protein from Arabidopsis that repress cell proliferation in developing leaves, inhibits cell division by blocking G1 → S transition in budding yeast. Cells expressing TCP4 protein with increased transcriptional activity fail to progress beyond G1 phase. By analyzing global transcriptional status of these cells, we show that expression of a number of cell cycle genes is altered. The possible mechanism of G1 → S arrest is discussed.

  6. Driving cycle characterization and generation, for design and control of fuel cell buses

    NARCIS (Netherlands)

    Tazelaar, E.; Bruinsma, J.; Veenhuizen, P.A.; Bosch, van den P.P.J.

    2009-01-01

    Optimization routines for battery, supercap and fuel cell stack in a fuel cell based propulsion system face two problems: the tendency to cycle beating and the necessity to maintain identical amounts of stored energy in battery and supercap at the start and end of the driving cycle used in the

  7. Mesenchymal stem cells promote cell invasion and migration and autophagy-induced epithelial-mesenchymal transition in A549 lung adenocarcinoma cells.

    Science.gov (United States)

    Luo, Dan; Hu, Shiyuan; Tang, Chunlan; Liu, Guoxiang

    2018-03-01

    Mesenchymal stem cells (MSCs) are recruited into the tumour microenvironment and promote tumour growth and metastasis. Tumour microenvironment-induced autophagy is considered to suppress primary tumour formation by impairing migration and invasion. Whether these recruited MSCs regulate tumour autophagy and whether autophagy affects tumour growth are controversial. Our data showed that MSCs promote autophagy activation, reactive oxygen species production, and epithelial-mesenchymal transition (EMT) as well as increased migration and invasion in A549 cells. Decreased expression of E-cadherin and increased expression of vimentin and Snail were observed in A549 cells cocultured with MSCs. Conversely, MSC coculture-mediated autophagy positively promoted tumour EMT. Autophagy inhibition suppressed MSC coculture-mediated EMT and reduced A549 cell migration and invasion slightly. Furthermore, the migratory and invasive abilities of A549 cells were additional increased when autophagy was further enhanced by rapamycin treatment. Taken together, this work suggests that microenvironments containing MSCs can promote autophagy activation for enhancing EMT; MSCs also increase the migratory and invasive abilities of A549 lung adenocarcinoma cells. Mesenchymal stem cell-containing microenvironments and MSC-induced autophagy signalling may be potential targets for blocking lung cancer cell migration and invasion. Copyright © 2018 John Wiley & Sons, Ltd.

  8. Retrospective evaluation of doxorubicin-piroxicam combination for the treatment of transitional cell carcinoma in dogs.

    Science.gov (United States)

    Robat, C; Burton, J; Thamm, D; Vail, D

    2013-02-01

    To determine whether doxorubicin-piroxicam combination is safe and has activity against transitional cell carcinoma in dogs. Data was collected retrospectively from 34 dogs from two institutions over a 6-year period. Signalment, clinical presentation, treatment specifics, adverse events, response, progression-free survival and overall survival time were evaluated. Dogs received doxorubicin every 3 weeks and daily piroxicam; 17 dogs (50%) had surgery. Clinical presentations were those typically reported for transitional cell carcinoma. Mean number of doses administered was 3·5. Of the 23 dogs with measurable disease, 14 (60·5%) had stable disease, 7 (30·5%) had progressive disease and 2 (9%) a partial response. Adverse events were generally manageable, and gastrointestinal in origin; one dog died of treatment-related complications. Overall median progression-free survival and overall survival were 103 and 168 days, respectively. Cytoreductive surgery did not result in prolongation of progression-free survival, but significantly prolonged overall survival. All dogs but one died as a result of disease progression. Doxorubicin-piroxicam combination therapy is well-tolerated in dogs with transitional cell carcinoma although progression-free survival, overall survival and biological response rates appear modest. Combination with surgery appears to offer a survival advantage; however, this may reflect tumour location and volume. Prospective studies are necessary to compare activity of combination doxorubicin-piroxicam to currently applied therapies. © 2013 British Small Animal Veterinary Association.

  9. Evaluation of the use of bioethanol fuelled buses based on ambient air pollution screening and on-road measurements

    Energy Technology Data Exchange (ETDEWEB)

    López-Aparicio, S., E-mail: sla@nilu.no; Hak, C.

    2013-05-01

    Mitigation measures to reduce greenhouse gas emissions may have adverse effects on urban air quality and human exposure to harmful pollutants. The use of bioethanol fuelled vehicles is increasing worldwide and may create new undesired pollution effects. Different measurement campaigns were performed in a pilot study to contribute to the understanding of the consequences associated with the use of bioethanol blended fuel (E95) on a series of pollutants. Ambient screening measurements of NO{sub 2}, O{sub 3}, acetic acid, formaldehyde and acetaldehyde were performed at different urban locations, exposed and not exposed to the circulation of bioethanol buses. In addition, volatile organic compounds were measured at the exhaust pipe of a bioethanol fuelled bus, both under idling conditions (carbonyls; DNPH cartridge) and under on-road driving conditions applying online monitoring (PTR-TOF). Higher ambient acetaldehyde values were measured at locations exposed to bioethanol fuelled buses than at locations not exposed, and very high acetaldehyde and acetic acid values were measured from the exhaust pipe during driving conditions (acetaldehyde > 150 ppm; acetic acid ≈ 20–30 ppm) and modelled at close distance to the bioethanol bus. Human exposure to high concentration of acetaldehyde is expected, and it may involve a significantly increased chance in developing cancer. The high concentration of acetic acid will involve odour annoyance and significant material degradation or corrosion. - Highlights: ► Acetaldehyde levels above 150 ppm were measured from the bioethanol bus. ► High acetic acid levels (20–30 ppm) were measured from the bioethanol bus. ► Demonstrated usefulness of PTR-MS to evaluate non-criteria pollutants ► High levels of acetaldehyde and acetic acid are estimated in the dispersion plume. ► Climate mitigation measures may have adverse impact on air quality.

  10. Evaluation of the use of bioethanol fuelled buses based on ambient air pollution screening and on-road measurements

    International Nuclear Information System (INIS)

    López-Aparicio, S.; Hak, C.

    2013-01-01

    Mitigation measures to reduce greenhouse gas emissions may have adverse effects on urban air quality and human exposure to harmful pollutants. The use of bioethanol fuelled vehicles is increasing worldwide and may create new undesired pollution effects. Different measurement campaigns were performed in a pilot study to contribute to the understanding of the consequences associated with the use of bioethanol blended fuel (E95) on a series of pollutants. Ambient screening measurements of NO 2 , O 3 , acetic acid, formaldehyde and acetaldehyde were performed at different urban locations, exposed and not exposed to the circulation of bioethanol buses. In addition, volatile organic compounds were measured at the exhaust pipe of a bioethanol fuelled bus, both under idling conditions (carbonyls; DNPH cartridge) and under on-road driving conditions applying online monitoring (PTR-TOF). Higher ambient acetaldehyde values were measured at locations exposed to bioethanol fuelled buses than at locations not exposed, and very high acetaldehyde and acetic acid values were measured from the exhaust pipe during driving conditions (acetaldehyde > 150 ppm; acetic acid ≈ 20–30 ppm) and modelled at close distance to the bioethanol bus. Human exposure to high concentration of acetaldehyde is expected, and it may involve a significantly increased chance in developing cancer. The high concentration of acetic acid will involve odour annoyance and significant material degradation or corrosion. - Highlights: ► Acetaldehyde levels above 150 ppm were measured from the bioethanol bus. ► High acetic acid levels (20–30 ppm) were measured from the bioethanol bus. ► Demonstrated usefulness of PTR-MS to evaluate non-criteria pollutants ► High levels of acetaldehyde and acetic acid are estimated in the dispersion plume. ► Climate mitigation measures may have adverse impact on air quality

  11. Cell kinetics of irradiated experimental tumors: cell transition from the non-proliferating to the proliferating pool

    International Nuclear Information System (INIS)

    Potmesil, M.; Goldfeder, A.

    1980-01-01

    In murine mammary carcinomas, parenchymal tumor cells with dense nucleoli traverse the cell cycle and divide, thus constituting the proliferating pool. Cells with trabeculate or ring-shaped nucleoli either proceed slowly through G 1 phase or are arrested in it. The role of these non-proliferating, G 1 phase-confined cells in tumor regeneration was studied in vivo after a subcurative dose of X-irradiation in two transplantable tumor lines. Tumor-bearing mice were continuously injected with methyl[ 3 H]thymidine before and after irradiation. Finally, the labeling was discontinued, mice injected with vincristine sulfate and cells arrested in metaphase were accumulated over 10-hrs. Two clearly delineated groups of vincristine-arrested mitoses emerged in autoradiograms prepared from tumor tissue at the time of starting tumor regrowth: one group with the silver-grain counts corresponding to the background level, the other with heavily labeled mitoses. As the only source of unlabeled mitoses was unlabeled G 1 phase-confined cells persisting in the tumor, this indicated cell transition from the non-proliferating to the proliferating pool, which took place in the initial phase of the tumor regrowth. Unlabeled progenitors have apparently remained in G 1 phase for at least 5-12 days after irradiation. (author)

  12. Low-floor bus design preferences of walking aid users during simulated boarding and alighting.

    Science.gov (United States)

    D'souza, Clive; Paquet, Victor; Lenker, James; Steinfeld, Edward; Bareria, Piyush

    2012-01-01

    Low-floor buses represent a significant improvement in accessible public transit for passengers with limited mobility. However, there is still a need for research on the inclusive design of transit buses to identify specific low-floor bus design conditions that are either particularly accommodating or challenging for passengers with functional and mobility impairments. These include doorway locations, seating configuration and the large front wheel-well covers that collectively impact boarding, alighting and interior movement of passengers. Findings from a laboratory study using a static full-scale simulation of a lowfloor bus to evaluate the impact of seating configuration and crowding on interior movement and accessibility for individuals with and without walking aids are presented (n=41). Simulated bus journeys that included boarding, fare payment, seating, and alighting were performed. Results from video observations and subjective assessments showed differences in boarding and alighting performance and users' perceptions of task difficulty. The need for assistive design features (e.g. handholds, stanchions), legroom and stowage space for walking aids was evident. These results demonstrate that specific design conditions in low-floor buses can significantly impact design preference among those who use walking aids. Consideration of ergonomics and inclusive design can therefore be used to improve the design of low-floor buses.

  13. Preprocessing with Photoshop Software on Microscopic Images of A549 Cells in Epithelial-Mesenchymal Transition.

    Science.gov (United States)

    Ren, Zhou-Xin; Yu, Hai-Bin; Shen, Jun-Ling; Li, Ya; Li, Jian-Sheng

    2015-06-01

    To establish a preprocessing method for cell morphometry in microscopic images of A549 cells in epithelial-mesenchymal transition (EMT). Adobe Photoshop CS2 (Adobe Systems, Inc.) was used for preprocessing the images. First, all images were processed for size uniformity and high distinguishability between the cell and background area. Then, a blank image with the same size and grids was established and cross points of the grids were added into a distinct color. The blank image was merged into a processed image. In the merged images, the cells with 1 or more cross points were chosen, and then the cell areas were enclosed and were replaced in a distinct color. Except for chosen cellular areas, all areas were changed into a unique hue. Three observers quantified roundness of cells in images with the image preprocess (IPP) or without the method (Controls), respectively. Furthermore, 1 observer measured the roundness 3 times with the 2 methods, respectively. The results between IPPs and Controls were compared for repeatability and reproducibility. As compared with the Control method, among 3 observers, use of the IPP method resulted in a higher number and a higher percentage of same-chosen cells in an image. The relative average deviation values of roundness, either for 3 observers or 1 observer, were significantly higher in Controls than in IPPs (p Photoshop, a chosen cell from an image was more objective, regular, and accurate, creating an increase of reproducibility and repeatability on morphometry of A549 cells in epithelial to mesenchymal transition.

  14. Human equilibrative nucleoside transporter-1 knockdown tunes cellular mechanics through epithelial-mesenchymal transition in pancreatic cancer cells.

    Directory of Open Access Journals (Sweden)

    Yeonju Lee

    Full Text Available We report cell mechanical changes in response to alteration of expression of the human equilibrative nucleoside transporter-1 (hENT1, a most abundant and widely distributed plasma membrane nucleoside transporter in human cells and/or tissues. Modulation of hENT1 expression level altered the stiffness of pancreatic cancer Capan-1 and Panc 03.27 cells, which was analyzed by atomic force microscopy (AFM and correlated to microfluidic platform. The hENT1 knockdown induced reduction of cellular stiffness in both of cells up to 70%. In addition, cellular phenotypic changes such as cell morphology, migration, and expression level of epithelial-mesenchymal transition (EMT markers were observed after hENT1 knockdown. Cells with suppressed hENT1 became elongated, migrated faster, and had reduced E-cadherin and elevated N-cadherin compared to parental cells which are consistent with epithelial-mesenchymal transition (EMT. Those cellular phenotypic changes closely correlated with changes in cellular stiffness. This study suggests that hENT1 expression level affects cellular phenotype and cell elastic behavior can be a physical biomarker for quantify hENT1 expression and detect phenotypic shift. Furthermore, cell mechanics can be a critical tool in detecting disease progression and response to therapy.

  15. Transitional cell carcinoma of the bladder in childhood: radiological findings and differential diagnosis

    International Nuclear Information System (INIS)

    Casado, L.; Mansilla, F.; Mansilla, M.D.; Marin, A.

    1998-01-01

    We present a case of transitional cell carcinoma of the bladder in an 11-year-old boy. The rarity of these tumors during childhood is pointed out. The radiological and ultrasonographic findings are described and the differential diagnosis is discussed with respect to other bladder tumors occurring in childhood. (Author) 11 refs

  16. The Effects of Bus Ridership on Airborne Particulate Matter (PM10) Concentrations

    OpenAIRE

    Jaeseok Her; Sungjin Park; Jae Seung Lee

    2016-01-01

    Air pollution caused by rapid urbanization and the increased use of private vehicles seriously affects citizens’ health. In order to alleviate air pollution, many cities have replaced diesel buses with compressed natural gas (CNG) buses that emit less exhaust gas. Urban planning strategies such as transit-oriented development (TOD) posit that reducing private vehicle use and increasing public transportation use would reduce air pollution levels. The present study examined the effects of bus r...

  17. Human cancer cells express Slug-based epithelial-mesenchymal transition gene expression signature obtained in vivo

    International Nuclear Information System (INIS)

    Anastassiou, Dimitris; Rumjantseva, Viktoria; Cheng, Weiyi; Huang, Jianzhong; Canoll, Peter D; Yamashiro, Darrell J; Kandel, Jessica J

    2011-01-01

    The biological mechanisms underlying cancer cell motility and invasiveness remain unclear, although it has been hypothesized that they involve some type of epithelial-mesenchymal transition (EMT). We used xenograft models of human cancer cells in immunocompromised mice, profiling the harvested tumors separately with species-specific probes and computationally analyzing the results. Here we show that human cancer cells express in vivo a precise multi-cancer invasion-associated gene expression signature that prominently includes many EMT markers, among them the transcription factor Slug, fibronectin, and α-SMA. We found that human, but not mouse, cells express the signature and Slug is the only upregulated EMT-inducing transcription factor. The signature is also present in samples from many publicly available cancer gene expression datasets, suggesting that it is produced by the cancer cells themselves in multiple cancer types, including nonepithelial cancers such as neuroblastoma. Furthermore, we found that the presence of the signature in human xenografted cells was associated with a downregulation of adipocyte markers in the mouse tissue adjacent to the invasive tumor, suggesting that the signature is triggered by contextual microenvironmental interactions when the cancer cells encounter adipocytes, as previously reported. The known, precise and consistent gene composition of this cancer mesenchymal transition signature, particularly when combined with simultaneous analysis of the adjacent microenvironment, provides unique opportunities for shedding light on the underlying mechanisms of cancer invasiveness as well as identifying potential diagnostic markers and targets for metastasis-inhibiting therapeutics

  18. Regulation of Pituitary Stem Cells by Epithelial to Mesenchymal Transition Events and Signaling Pathways

    Science.gov (United States)

    Cheung, Leonard Y. M.; Davis, Shannon W.; Brinkmeier, Michelle L.; Camper, Sally A.; Pérez-Millán, María Inés

    2017-01-01

    The anterior pituitary gland is comprised of specialized cell-types that produce and secrete polypeptide hormones in response to hypothalamic input and feedback from target organs. These specialized cells arise from stem cells that express SOX2 and the pituitary transcription factor PROP1, which is necessary to establish the stem cell pool and promote an epithelial to mesenchymal-like transition, releasing progenitors from the niche. The adult anterior pituitary responds to physiological challenge by mobilizing the SOX2-expressing progenitor pool and producing additional hormone-producing cells. Knowledge of the role of signaling pathways and extracellular matrix components in these processes may lead to improvements in the efficiency of differentiation of embryonic stem cells or induced pluripotent stem cells into hormone producing cells in vitro. Advances in our basic understanding of pituitary stem cell regulation and differentiation may lead to improved diagnosis and treatment for patients with hypopituitarism. PMID:27650955

  19. Рassenger survey on public transport in Zhitomir and evaluation of the main technical and operational parameters for the choice of city buses

    Directory of Open Access Journals (Sweden)

    Rudzynskyi V.V.

    2016-08-01

    Full Text Available The parameters of the passenger movements in the direction of public transport in Zhitomir are defined and conformity assessment of technical and operational parameters of urban shuttle buses is folded. Firstly, the amount of passenger traffic affects the optimal choice of passenger vehicles and secondly, the intensity of road traffic on the streets of areas where passengers pass routes. It should also be kept in mind that passenger traffic can fluctuate significantly depending on the time of day and days of the week. But virtually all carriers can be replaced within days with rolling at a large passenger capacity, and vice versa. Therefore, the choice of one type of rolling stock, the capacity of which is set taking into account the data on hourly passenger capacity on the most loaded part of the route up to an hour "peak", or its capacity per day on the route as a whole. Thus the research work on inspection of passenger-route passenger transport, and public electric transport in Zhitomir is conducted. Primary data was estimated to select the main criteria for urban passenger bus. It was found that the buses in the "peak" hours move on passenger congestion. Preliminary conclusions and recommendations on the criteria of optimal rolling of choice for the city bus route network are provided.

  20. Hypoxia inducible factor-1α-dependent epithelial to mesenchymal transition under hypoxic conditions in prostate cancer cells.

    Science.gov (United States)

    Li, Mingchuan; Wang, Yong Xing; Luo, Yong; Zhao, Jiahui; Li, Qing; Zhang, Jiao; Jiang, Yongguang

    2016-07-01

    Prostate cancer is the most commonly diagnosed cancer in men and the second leading cause of cancer death. Hypoxia is an environmental stimulus that plays an important role in the development and cancer progression especially for solid tumors. The key regulator under hypoxic conditions is stabilized hypoxia-inducible factor (HIF)-1α. In the present study, immune-fluorescent staining, siRNAs, qRT-PC, immunoblotting, cell migration and invasion assays were carried out to test typical epithelial to mesenchymal transition under hypoxia and the key regulators of this process in PC3, a human prostate cancer cell line. Our data demonstrated that hypoxia induces diverse molecular, phenotypic and functional changes in prostate cancer cells that are consistent with EMT. We also showed that a cell signal factor such as HIF-1α, which might be stabilized under hypoxic environment, is involved in EMT and cancer cell invasive potency. The induced hypoxia could be blocked by HIF-1α gene silencing and reoxygenation of EMT in prostate cancer cells, hypoxia partially reversed accompanied by a process of mesenchymal-epithelial reverting transition (MErT). EMT might be induced by activation of HIF-1α-dependent cell signaling in hypoxic prostate cancer cells.

  1. Mitochondrial permeability transition and cell death: the role of cyclophilin D

    Directory of Open Access Journals (Sweden)

    Sabzali eJavadov

    2013-04-01

    Full Text Available Mitochondria serve as a powerhouse which provides near 90% of ATP necessary for cell life. However, recent studies provide strong evidence that mitochondria also play a central role in cell death. Irreversible mitochondrial permeability transition (mPT at high conductance in response to oxidative or other cellular stresses is accompanied by formation of pathological and non-specific mPT pores (mPTP in the inner membrane of mitochondria. Mitochondrial PTP can serve as a target to prevent cell death under pathological conditions such as cardiac and brain ischemia/reperfusion injury and diabetes. On the other hand, mPTP can be used as an executioner to specifically induce cell death thus blocking tumorigenesis in cancer diseases. Despite many studies, the molecular identity of the mPTP remains unclear. At present, cyclophilin D (CyP-D represents the only mPTP protein which plays an essential role in pore formation. This review will discuss direct and indirect mechanisms underlying CyP-D interaction with a target protein of the mPTP complex. Understanding of the mechanisms of mPTP formation will be helpful to further develop new pharmacological agents targeting mitochondria-mediated cell death.

  2. Robust Clamping Force Control of an Electro-Mechanical Brake System for Application to Commercial City Buses

    Directory of Open Access Journals (Sweden)

    Sangjune Eum

    2017-02-01

    Full Text Available This paper proposes a sensor-less robust force control method for improving the control performance of an electro-mechanical brake (EMB which is applicable to commercial city buses. The EMB generates the accurate clamping force commanded by a driver through an independent motor control at each wheel instead of using existing mechanical components. In general, an EMB undergoes parameter variation and a backdrivability problem. For this reason, the cascade control strategy (e.g., force-position cascade control structure is proposed and the disturbance observer is employed to enhance control robustness against model variations. Additionally, this paper proposed the clamping force estimation method for a sensor-less control, i.e., the clamping force observer (CFO. Finally, in order to confirm the performance and effectiveness of a proposed robust control method, several experiments are performed and analyzed.

  3. Alternative Fuel Vehicle Publications | Transportation Research | NREL

    Science.gov (United States)

    vehicle evaluations. Biodiesel Regional Transit District Effect of B20 and Low Aromatic Diesel on Transit Buses Operated on Biodiesel Blends. Kenneth Proc, Robb Barnitt, Robert Hayes, Matthew Ratcliff, and Robert McCormick. (2006) Operating Experience and Teardown Analysis for Engines Operated on Biodiesel

  4. Safety evaluation of a hydrogen fueled transit bus

    Energy Technology Data Exchange (ETDEWEB)

    Coutts, D.A.; Thomas, J.K.; Hovis, G.L.; Wu, T.T. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1997-12-31

    Hydrogen fueled vehicle demonstration projects must satisfy management and regulator safety expectations. This is often accomplished using hazard and safety analyses. Such an analysis has been completed to evaluate the safety of the H2Fuel bus to be operated in Augusta, Georgia. The evaluation methods and criteria used reflect the Department of Energy`s graded approach for qualifying and documenting nuclear and chemical facility safety. The work focused on the storage and distribution of hydrogen as the bus motor fuel with emphases on the technical and operational aspects of using metal hydride beds to store hydrogen. The safety evaluation demonstrated that the operation of the H2Fuel bus represents a moderate risk. This is the same risk level determined for operation of conventionally powered transit buses in the United States. By the same criteria, private passenger automobile travel in the United States is considered a high risk. The evaluation also identified several design and operational modifications that resulted in improved safety, operability, and reliability. The hazard assessment methodology used in this project has widespread applicability to other innovative operations and systems, and the techniques can serve as a template for other similar projects.

  5. Research and Development of Zinc Air Fuel Cell To Achieve Commercialization Final Report CRADA No. TC-1544-98

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, J. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Haley, H. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-28

    The specific goal of this project was to advance the development of the zinc air fuel cell (ZAFC) towards commercial readiness in different mobile applications, including motor bikes, passenger cars, vans, buses and off-road vehicles (golf carts, factory equipment), and different stationary applications including generator sets, uninterruptible power systems and electric utility loading leveling and distributive power.

  6. Renal transitional cell carcinoma: a sonographic and radiological correlation

    International Nuclear Information System (INIS)

    Prando, A.; Marins, J.L.C.; Prando, D.; Pereira, R.M.

    1984-01-01

    A sonographic study was performed on nine patients with renal transitional cell carcinoma and the findings correlated with those of excretory urography, retrograde and/or antegrade pyelography. In six patients the correct diagnosis was considered mainly by the radiological features. In the remaining three patients, due to its unusual manifestations, this diagnosis was accomplished only by sonography. A small echogenic mass at the peryphery of a chronic hydronephrotic kidney, a huge complex mass due to a multiple arborescent papilary tumor and a demonstration of a mass in a presumptive renal pelvic inflammatory disease, respectively, represented these uncommon aspects. The spectrum of features of this entity and the related differential diagnosis are also presented. (Author) [pt

  7. Distribution of Neuroendocrine Cells in the Transition Zone of the Prostate

    Directory of Open Access Journals (Sweden)

    Yuki Kyoda

    2017-01-01

    Full Text Available Objectives. To evaluate the distribution of neuroendocrine (NE cells which may influence the development of benign prostatic hyperplasia (BPH in the transition zone (TZ. Methods. We reviewed specimens from 80 patients who underwent radical prostatectomy in our institution and evaluated the density of NE cells in the TZ. They were histologically classified into 3 groups: those with no adenomatous nodule in the TZ (group A, those with small nodules with normal epithelium and stroma around them in the TZ (group B, and those with large nodules occupying the TZ (group C. In the patients of group B, intra-adenoma (adenomatous nodules and extra-adenoma (normal tissue NE cells in the TZ were separately counted. Results. There were 22, 23, and 35 patients in groups A, B, and C, respectively. The median density of NE cells in the TZ of group B patients, 2.80/mm2, was significantly higher than that of NE cells in group A, 1.43/mm2, and group C, 0.61/mm2 (p<0.001. In group B, the median density of extra-adenoma NE cells was significantly higher than that of intra-adenoma. Conclusions. Many NE cells exist around small adenoma in the TZ. NE cells may influence the initial growth of BPH in a paracrine fashion. Trial Registration. This study approved by our institutional review board was retrospectively registered (#272-14.

  8. Overexpression of catalase delays G0/G1- to S-phase transition during cell cycle progression in mouse aortic endothelial cells.

    Science.gov (United States)

    Onumah, Ogbeyalu E; Jules, George E; Zhao, Yanfeng; Zhou, LiChun; Yang, Hong; Guo, ZhongMao

    2009-06-15

    Although it is understood that hydrogen peroxide (H(2)O(2)) promotes cellular proliferation, little is known about its role in endothelial cell cycle progression. To assess the regulatory role of endogenously produced H(2)O(2) in cell cycle progression, we studied the cell cycle progression in mouse aortic endothelial cells (MAECs) obtained from mice overexpressing a human catalase transgene (hCatTg), which destroys H(2)O(2). The hCatTg MAECs displayed a prolonged doubling time compared to wild-type controls (44.0 +/- 4.7 h versus 28.6 +/- 0.8 h, pcatalase inhibitor, prevented the observed diminished growth rate in hCatTg MAECs. Inhibition of catalase activity with aminotriazole abrogated catalase overexpression-induced antiproliferative action. Flow cytometry analysis indicated that the prolonged doubling time was principally due to an extended G(0)/G(1) phase in hCatTg MAECs compared to the wild-type cells (25.0 +/- 0.9 h versus 15.9 +/- 1.4 h, pinhibitors, p21 and p27, which inhibit the Cdk activity required for the G(0)/G(1)- to S-phase transition. Knockdown of p21 and/or p27 attenuated the antiproliferative effect of catalase overexpression in MAECs. These results, together with the fact that catalase is an H(2)O(2) scavenger, suggest that endogenously produced H(2)O(2) mediates MAEC proliferation by fostering the transition from G(0)/G(1) to S phase.

  9. GSK3β attenuates TGF-β1 induced epithelial–mesenchymal transition and metabolic alterations in ARPE-19 cells

    International Nuclear Information System (INIS)

    Huang, Li; Zhang, Cheng; Su, Li; Song, Zhengyu

    2017-01-01

    While TGF-β1 is known to induce epithelial–mesenchymal transition (EMT), a major factor in the pathogenesis of proliferative vitreoretinopathy (PVR), in ARPE-19 cells. The molecular pathways involved in EMT formation have not yet to be fully characterized. In this study, we have found that TGF-β1-mediated induction of EMT in ARPE-19 cells varied in a dose- and time-dependent manner. Specifically, TGF-β1 inhibited GSK-3β by accelerating phosphorylation at ser9. GSK-3β inhibitor or knockdown of GSK-3β resulted in enhanced TGF-β1-mediated EMT, migration and collagen contraction in ARPE-19 cells, which were then abrogated by GSK-3β overexpression and PI3K/AKT inhibitor. Importantly, GSK-3β also mediated metabolic reprogramming in TGF-β1-treated cells. Our results indicate that GSK-3β plays a pivotal role in TGF-β1-mediated EMT in ARPE-19 cells. - Highlights: • GSK-3β mediates epithelial-mesenchymal transition in TGF-β1 treated ARPE-19 cells. • GSK-3β regulates cell migration and collagen contraction of ARPE-19 cells. • TGF-β1 induces extracellular metabolomic changes of ARPE-19 cells via a GSK-3β-dependent mechanism.

  10. TGF-β1 induced epithelial to mesenchymal transition (EMT in human bronchial epithelial cells is enhanced by IL-1β but not abrogated by corticosteroids

    Directory of Open Access Journals (Sweden)

    Zuraw Bruce L

    2009-10-01

    Full Text Available Abstract Background Chronic persistent asthma is characterized by ongoing airway inflammation and airway remodeling. The processes leading to airway remodeling are poorly understood, and there is increasing evidence that even aggressive anti-inflammatory therapy does not completely prevent this process. We sought to investigate whether TGFβ1 stimulates bronchial epithelial cells to undergo transition to a mesenchymal phenotype, and whether this transition can be abrogated by corticosteroid treatment or enhanced by the pro-inflammatory cytokine IL-1β. Methods BEAS-2B and primary normal human bronchial epithelial cells were stimulated with TGFβ1 and expression of epithelial and mesenchymal markers assessed by quantitative real-time PCR, immunoblotting, immunofluorescence microscopy and zymography. In some cases the epithelial cells were also incubated with corticosteroids or IL-1β. Results were analyzed using non-parametric statistical tests. Results Treatment of BEAS-2B or primary human bronchial epithelial cells with TGFβ1 significantly reduced the expression level of the epithelial adherence junction protein E-cadherin. TGFβ1 then markedly induced mesenchymal marker proteins such as collagen I, tenascin C, fibronectin and α-smooth muscle actin mRNA in a dose dependant manner. The process of mesenchymal transition was accompanied by a morphological change towards a more spindle shaped fibroblast cell type with a more motile and invasive phenotype. Corticosteroid pre-treatment did not significantly alter the TGFβ1 induced transition but IL-1β enhanced the transition. Conclusion Our results indicate, that TGFβ1 can induce mesenchymal transition in the bronchial epithelial cell line and primary cells. Since asthma has been strongly associated with increased expression of TGFβ1 in the airway, epithelial to mesenchymal transition may contribute to the contractile and fibrotic remodeling process that accompanies chronic asthma.

  11. Epigenetic modulation of the miR-200 family is associated with transition to a breast cancer stem-cell-like state.

    Science.gov (United States)

    Lim, Yat-Yuen; Wright, Josephine A; Attema, Joanne L; Gregory, Philip A; Bert, Andrew G; Smith, Eric; Thomas, Daniel; Lopez, Angel F; Drew, Paul A; Khew-Goodall, Yeesim; Goodall, Gregory J

    2013-05-15

    The miR-200 family is a key regulator of the epithelial-mesenchymal transition, however, its role in controlling the transition between cancer stem-cell-like and non-stem-cell-like phenotypes is not well understood. We utilized immortalized human mammary epithelial (HMLE) cells to investigate the regulation of the miR-200 family during their conversion to a stem-like phenotype. HMLE cells were found to be capable of spontaneous conversion from a non-stem to a stem-like phenotype and this conversion was accompanied by the loss of miR-200 expression. Stem-like cell fractions isolated from metastatic breast cancers also displayed loss of miR-200 indicating similar molecular changes may occur during breast cancer progression. The phenotypic change observed in HMLE cells was directly controlled by miR-200 because restoration of its expression decreased stem-like properties while promoting a transition to an epithelial phenotype. Investigation of the mechanisms controlling miR-200 expression revealed both DNA methylation and histone modifications were significantly altered in the stem-like and non-stem phenotypes. In particular, in the stem-like phenotype, the miR-200b-200a-429 cluster was silenced primarily through polycomb group-mediated histone modifications whereas the miR-200c-141 cluster was repressed by DNA methylation. These results indicate that the miR-200 family plays a crucial role in the transition between stem-like and non-stem phenotypes and that distinct epigenetic-based mechanisms regulate each miR-200 gene in this process. Therapy targeted against miR-200 family members and epigenetic modifications might therefore be applicable to breast cancer.

  12. Epithelial-mesenchymal transition: a hallmark in metastasis formation linking circulating tumor cells and cancer stem cells.

    Science.gov (United States)

    Książkiewicz, Magdalena; Markiewicz, Aleksandra; Zaczek, Anna J

    2012-01-01

    The occurrence of either regional or distant metastases is an indicator of poor prognosis for cancer patients. The mechanism of their formation has not yet been fully uncovered, which limits the possibility of developing new therapeutic strategies. Nevertheless, the discovery of circulating tumor cells (CTCs), which are responsible for tumor dissemination, and cancer stem cells (CSCs), required for tumor growth maintenance, shed light on the metastatic cascade. It seems that CTCs and CSCs are not necessarily separate populations of cancer cells, as CTCs generated in the process of epithelial-mesenchymal transition (EMT) can bear features characteristic of CSCs. This article describes the mechanisms of CTC and CSC formation and characterizes their molecular hallmarks. Moreover, we present different types of EMT occurring in physiological and pathological conditions, and we demonstrate its crucial role in providing CTCs with a CSC phenotype. The article delineates molecular changes acquired by cancer cells undergoing EMT that facilitate metastasis formation. Deeper understanding of those processes is of fundamental importance for the development of new strategies of early cancer detection and effective cancer treatment approaches that will be translated into clinical practice. Copyright © 2012 S. Karger AG, Basel.

  13. Interlinked bistable mechanisms generate robust mitotic transitions.

    Science.gov (United States)

    Hutter, Lukas H; Rata, Scott; Hochegger, Helfrid; Novák, Béla

    2017-10-18

    The transitions between phases of the cell cycle have evolved to be robust and switch-like, which ensures temporal separation of DNA replication, sister chromatid separation, and cell division. Mathematical models describing the biochemical interaction networks of cell cycle regulators attribute these properties to underlying bistable switches, which inherently generate robust, switch-like, and irreversible transitions between states. We have recently presented new mathematical models for two control systems that regulate crucial transitions in the cell cycle: mitotic entry and exit, 1 and the mitotic checkpoint. 2 Each of the two control systems is characterized by two interlinked bistable switches. In the case of mitotic checkpoint control, these switches are mutually activating, whereas in the case of the mitotic entry/exit network, the switches are mutually inhibiting. In this Perspective we describe the qualitative features of these regulatory motifs and show that having two interlinked bistable mechanisms further enhances robustness and irreversibility. We speculate that these network motifs also underlie other cell cycle transitions and cellular transitions between distinct biochemical states.

  14. Pregnancy alters the circulating B cell compartment in atopic asthmatic women, and transitional B cells are positively associated with the development of allergy manifestations in their progeny.

    Science.gov (United States)

    Martins, Catarina; Lima, Jorge; Nunes, Glória; Borrego, Luís Miguel

    2016-12-01

    Maternal atopy is a risk factor for allergy. B cells are poorly studied in reproduction and atopy. We aimed to assess how pregnancy affects B cells in atopic women and whether B cells relate to allergic manifestations in offspring. Women with and without atopic asthma, pregnant and non-pregnant were enrolled for the study, and circulating B cells were evaluated by flow cytometry, using CD19, CD27, CD38, IgD, and IgM. Compared to healthy non-pregnant, atopic asthmatic non-pregnant (ANP) women presented increased B cell counts, enlarged memory subsets, less transitional cells, and plasmablasts. Atopic asthmatic pregnant (AP) and healthy pregnant (HP) women showed similarities: reduced B cell counts and percentages, fewer memory cells, especially switched, and higher plasmablast percentages. Transitional B cell percentages were increased in AP women with allergic manifestations in their progeny. Atopic asthmatic non-pregnant women have a distinctive B cell compartment. B cells change in pregnancy, similarly in AP and HP women. The recognition that AP women with allergy in their progeny have a typical immune profile may help, in the future, the adoption of preventive measures to avoid the manifestation of allergic diseases in their newborns. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Activation of a cGMP-sensitive calcium-dependent chloride channel may cause transition from calcium waves to whole-cell oscillations in smooth muscle cells

    DEFF Research Database (Denmark)

    Jacobsen, Jens Christian; Aalkjær, Christian; Nilsson, Holger

    2007-01-01

    waves sweeping through the cytoplasm when the SR is stimulated to release calcium. A rise in cyclic guanosine monophosphate (cGMP) leads to the experimentally observed transition from waves to whole-cell calcium oscillations. At the same time membrane potential starts to oscillate and the frequency...... approximately doubles. In this transition, the simulated results point to a key role for a recently discovered cGMP-sensitive calcium-dependent chloride channel. This channel depolarizes the membrane in response to calcium released from the SR. In turn, depolarization causes uniform opening of L-type calcium...... onset of oscillations in membrane potential within the individual cell may underlie sudden intercellular synchronization and the appearance of vasomotion. Key words: Vasomotion, Chloride channel, cGMP, Mathematical model, Calcium waves....

  16. Phenotypic plasticity and epithelial-to-mesenchymal transition in the behaviour and therapeutic response of oral squamous cell carcinoma.

    Science.gov (United States)

    Vig, Navin; Mackenzie, Ian C; Biddle, Adrian

    2015-10-01

    It is increasingly recognised that phenotypic plasticity, apparently driven by epigenetic mechanisms, plays a key role in tumour behaviour and markedly influences the important processes of therapeutic survival and metastasis. An important source of plasticity in malignancy is epithelial-to-mesenchymal transition (EMT), a common epigenetically controlled event that results in transition of malignant cells between different phenotypic states that confer motility and enhance survival. In this review, we discuss the importance of phenotypic plasticity and its contribution to cellular heterogeneity in oral squamous cell carcinoma with emphasis on aspects of drug resistance and EMT. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Impact of Spanish electricity mix, over the period 2008–2030, on the Life Cycle energy consumption and GHG emissions of Electric, Hybrid Diesel-Electric, Fuel Cell Hybrid and Diesel Bus of the Madrid Transportation System

    International Nuclear Information System (INIS)

    García Sánchez, Juan Antonio; López Martínez, José María; Lumbreras Martín, Julio; Flores Holgado, María Nuria; Aguilar Morales, Hansel

    2013-01-01

    Highlights: • We assess the performance of 4 buses that run on different alternative fuel types and technologies. • The buses assessed are Fuel Cell-Hybrid Bus, Hybrid Diesel-Electric Bus, Battery Electric Bus, and a Diesel Bus. • We examine the environmental impact caused by the Life Cycle of each vehicle technology, fossil fuel and energy carrier. • Life Cycle of Battery Electric Bus shows that it has a big potential of improvement in terms of environmental impact. - Abstract: In spite of the advanced research in automotive technology, and the improvement of fuels, the road transport sector continues to be an environmental concern, since the increase in transport demand is offsetting the effects of these technological improvements. Therefore, this poses the following question: what combination of technology and fuel is more efficient in terms of energy consumption and green house gas (GHG) emissions? To fully address this question it is necessary to carry out a Life Cycle Assessment (LCA). This paper presents a global LCA of 4 buses that run on the following fuel types and technologies: (1) Fuel Cell- Hybrid Bus, (2) Hybrid Diesel-Electric Bus (series configuration), (3) Battery Electric Bus and (4) Combustion Ignition Engine Bus. The impact categories assessed are: primary energy consumption, fossil energy and GHG emissions. Among the principal results, we can conclude that the Global LCA of buses (3) and (1) (which are the more sensitive pathways to the electricity mix variation) have for the 2008–2030 period a room for improvement of 25.62% and 28.16% in terms of efficiency of fossil energy consumption and a potential GHG emission reduction of 28.70% and 30.88% respectively

  18. Donor-derived stem-cells and epithelial mesenchymal transition in squamous cell carcinoma in transplant recipients.

    Science.gov (United States)

    Verneuil, Laurence; Leboeuf, Christophe; Bousquet, Guilhem; Brugiere, Charlotte; Elbouchtaoui, Morad; Plassa, Louis-François; Peraldi, Marie-Noelle; Lebbé, Celeste; Ratajczak, Philippe; Janin, Anne

    2015-12-08

    Skin squamous-cell-carcinoma (SCC), is the main complication in long-term kidney-transplant recipients, and it can include donor-derived cells. Preclinical models demonstrated the involvement of epithelial mesenchymal transition (EMT) in the progression of skin SCC, and the role of Snail, an EMT transcription factor, in cancer stem-cell survival and expansion.Here, we studied stem-cells and EMT expression in SCCs and concomitant actinic keratoses (AK) in kidney-transplant recipients. In SCC and AK in 3 female recipients of male kidney-transplants, donor-derived Y chromosome in epidermal stem cells was assessed using combined XY-FISH/CD133 immunostaining, and digital-droplet-PCR on laser-microdissected CD133 expressing epidermal cells.For EMT study, double immunostainings of CD133 with vimentin or snail and slug, electron microscopy and immunostainings of keratinocytes junctions were performed. Digital droplet PCR was used to check CDH1 (E-cadherin) expression level in laser-microdissected cells co-expressing CD133 and vimentin or snail and slug.The numbers of Y-chromosome were assessed using digital droplet PCR in laser-microdissected cells co-expressing CD133 and vimentin, or snail and slug, and in CD133 positive cells not expressing any EMT maker. We identified donor-derived stem-cells in basal layers and invasive areas in all skin SCCs and in concomitant AKs, but not in surrounding normal skin.The donor-derived stem-cells expressed the EMT markers, vimentin, snail and slug in SCCs but not in AKs. The expression of the EMT transcription factor, SNAI1, was higher in stem-cells when they expressed vimentin. They were located in invasive areas of SCCs. In these areas, the expressions of claudin-1 and desmoglein 1 were reduced or absent, and within the basal layer there were features of basal membrane disappearance.Donor-derived stem cells were in larger numbers in stem cells co-expressing vimentin or snail and slug than in stem cells not expressing any EMT marker

  19. Research of TGF-beta1 Inducing Lung Adencarcinoma PC9 Cells to Mesenchymal Cells Transition

    Directory of Open Access Journals (Sweden)

    Xiaofeng CHEN

    2010-01-01

    Full Text Available Background and objective It has been proven that epithelial-mesenchymal transition (EMT not only correlated with embryonic development but also could promote tumor invasion and metastasis. Transforming growth factor beta-1 (TGF-β1 has been identified as the main inducer of tumor EMT. The aim of this study was to investigate the effects of TGF-β1 on EMT and PI3K/AKT signaling pathway in lung adencarcinoma PC9 cells. Methods Cultured PC9 cells were treated with different concentrations of TGF-β1 for 48 h. The morphological changes were observed under phase-contrast microscopy; EMT relative marker protein changes were assessed by Western blot and immunoflurescence staining. In addition, the expression of AKT and P-AKT were also measured by Western blot. Results The data showed that TGF-β1 could induce PC9 morphological alteration from epithelial to mesenchymal and upregulate the expression of mesenchymal maker protein Fibronectin. Obviously, the expression of P-AKT was downregulated by TGF-β1 treatment for 48 h. Conclusion TGF-β1 might induce EMT of PC9 cells , accompanied by the changes of PI3K/AKT signaling pathway.

  20. 27-hydroxycholesterol induces the transition of MCF7 cells into a mesenchymal phenotype.

    Science.gov (United States)

    Torres, Cristian G; Ramírez, María E; Cruz, Pamela; Epuñan, María J; Valladares, Luis E; Sierralta, Walter D

    2011-08-01

    A decrease in the expression of E-cadherin and β-catenin, paralleling the loss of adherens junction complex, was observed in MCF7 cells exposed for longer than 48 h to 2 µM 27-hydroxycholesterol (27OHC), indicating an epithelial-mesenchymal transition (EMT). Upon removal of 27OHC from the culture medium, the cells released by the exposure of 72 h to the oxysterol grew as loosely packed cell groups. In these cells, accumulation of E-cadherin and β-catenin in the cytoplasm and the prolonged expression of epidermal growth factor receptor 2 (EGFR2/neu) in the plasma membrane were observed, suggesting that the acquired phenotype was related to the expression of this tyrosine kinase-growth factor receptor. The results presented here are discussed on the basis of the claimed relationship between 27OHC, hypercholesterolemia, macrophage infiltration and therapy-resistant ERα+ breast cancer incidence.

  1. NFBD1/MDC1 participates in the regulation of G2/M transition in mammalian cells

    International Nuclear Information System (INIS)

    Bu, Youquan; Suenaga, Yusuke; Okoshi, Rintaro; Sang, Meixiang; Kubo, Natsumi; Song, Fangzhou; Nakagawara, Akira; Ozaki, Toshinori

    2010-01-01

    NFBD1/MDC1 is a large nuclear protein involved in the early cellular response to DNA damage. Upon DNA damage, NFBD1 has an ability to facilitate the efficient DNA repair. In the present study, we have found that, in addition to DNA damage response, NFBD1 plays a critical role in the regulation of G2/M transition. Expression study using synchronized HeLa cells demonstrated that, like the mitotic kinase Plk1, NFBD1 expression level is maximal in G2/M-phase of the cell cycle. siRNA-mediated knockdown of NFBD1 resulted in G2/M arrest as well as simultaneous apoptosis in association with a significant increase in the amounts of γH2AX and pro-apoptotic p73. Since a remarkable down-regulation of mitotic phospho-histone H3 was detectable in NFBD1-knocked down cells, it is likely that knocking down of NFBD1 inhibits G2/M transition. Taken together, our present findings suggest that NFBD1 has a pivotal role in the regulation of proper mitotic entry.

  2. A Model for the Stop Planning and Timetables of Customized Buses.

    Directory of Open Access Journals (Sweden)

    Jihui Ma

    Full Text Available Customized buses (CBs are a new mode of public transportation and an important part of diversified public transportation, providing advanced, attractive and user-led service. The operational activity of a CB is planned by aggregating space-time demand and similar passenger travel demands. Based on an analysis of domestic and international research and the current development of CBs in China and considering passenger travel data, this paper studies the problems associated with the operation of CBs, such as stop selection, line planning and timetables, and establishes a model for the stop planning and timetables of CBs. The improved immune genetic algorithm (IIGA is used to solve the model with regard to the following: 1 multiple population design and transport operator design, 2 memory library design, 3 mutation probability design and crossover probability design, and 4 the fitness calculation of the gene segment. Finally, a real-world example in Beijing is calculated, and the model and solution results are verified and analyzed. The results illustrate that the IIGA solves the model and is superior to the basic genetic algorithm in terms of the number of passengers, travel time, average passenger travel time, average passenger arrival time ahead of schedule and total line revenue. This study covers the key issues involving operational systems of CBs, combines theoretical research and empirical analysis, and provides a theoretical foundation for the planning and operation of CBs.

  3. Simulation on the consumption-oriented evaluation of ventilation concepts for buses; Simulation zur verbrauchsorientierten Bewertung von Omnibus-Klimatisierungskonzepten

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Christian; Foersterling, Sven; Strupp, Christian; Lemke, Nicholas [TLK Thermo GmbH, Braunschweig (Germany); Sonnekalb, Michael [Konvekta AG, Schwalmstadt (Germany); Koehler, Juergen [Technische Univ. Braunschweig (Germany)

    2012-11-01

    This paper presents different air conditioning system and climate control concepts for buses. These concepts are investigated based on a complete vehicle simulation in order to perform a close-to-reality assessment. The effects of various control strategies are examined in a comparative approach using boundary conditions which are based on on-the-road-relevant test cycles and climatic conditions. The focus of this study is the evaluation of the total energy consumption. Moreover, an analysis of air conditioning systems with conventional and natural refrigerants is presented (R-134a and R-744). Based on simulation results, a high fuel-saving concept is developed and tested in a virtual test drive, in order to present a specific method of control strategy evaluation with transient boundary and environmental conditions. (orig.)

  4. Hydrogen Village : creating hydrogen and fuel cell communities

    International Nuclear Information System (INIS)

    Smith, G.R.

    2009-01-01

    The Hydrogen Village (H2V) is a collaborative public-private partnership administered through Hydrogen and Fuel Cells Canada and funded by the Governments of Canada and Ontario. This end user-driven, market development program accelerates the commercialization of hydrogen and fuel cell (FC) technologies throughout the Greater Toronto Area (GTA). The program targets 3 specific aspects of market development, notably deployment of near market technologies in community based stationary and mobile applications; development of a coordinated hydrogen delivery and equipment service infrastructure; and societal factors involving corporate policy and public education. This presentation focused on lessons learned through outreach programs and the deployment of solid oxide fuel cell (SOFC) heat and power generation; indoor and outdoor fuel cell back up power systems; fuel cell-powered forklifts, delivery vehicles, and utility vehicles; hydrogen internal combustion engine powered shuttle buses, sedans, parade float; hydrogen production/refueling stations in the downtown core; and temporary fuel cell power systems

  5. Evidence for epithelial-mesenchymal transition in cancer stem-like cells derived from carcinoma cell lines of the cervix uteri.

    Science.gov (United States)

    Lin, Jiaying; Liu, Xishi; Ding, Ding

    2015-01-01

    The cancer stem cell (CSC) paradigm is one possible way to understand the genesis of cancer, and cervical cancer in particular. We quantified and enriched ALDH1(+) cells within cervical cancer cell lines and subsequently characterized their phenotypical and functional properties like invasion capacity and epithelial-mesenchymal transition (EMT). ALDH1 expression in spheroid-derived cells (SDC) and the parental monolayer-derived cell (MDC) line was compared by flow-cytometry. Invasion capability was evaluated by Matrigel assay and expression of EMT-related genes Twist 1, Twist 2, Snail 1, Snail 2, Vimentin and E-cadherin by real-time PCR. ALDH1 expression was significantly higher in SDC. ALDH1(+) cells showed increased colony-formation. SDC expressed lower levels of E-cadherin and elevated levels of Twist 1, Twist 2, Snail 1, Snail 2 and Vimentin compared to MDC. Cervical cancer cell lines harbor potential CSC, characterized by ALDH1 expression as well as properties like invasiveness, colony-forming ability, and EMT. CSC can be enriched by anchorage-independent culture techniques, which may be important for the investigation of their contribution to therapy resistance, tumor recurrence and metastasis.

  6. Claudin-1 promotes TNF-α-induced epithelial-mesenchymal transition and migration in colorectal adenocarcinoma cells

    International Nuclear Information System (INIS)

    Bhat, Ajaz A.; Ahmad, Rizwan; Uppada, SrijayaPrakash B.; Singh, Amar B.; Dhawan, Punita

    2016-01-01

    Epithelial-mesenchymal transition (EMT) is an important mechanism in cancer progression and malignancy including colorectal cancer (CRC). Importantly, inflammatory mediators are critical constituents of the local tumor environment and an intimate link between CRC progression and inflammation is now validated. We and others have reported key role of the deregulated claudin-1 expression in colon carcinogenesis including colitis-associated colon cancer (CAC). However, the causal association between claudin-1 expression and inflammation-induced colon cancer progression remains unclear. Here we demonstrate, TNF-α, a pro-inflammatory cytokine, regulates claudin-1 to modulate epithelial to mesenchymal transition (EMT) and migration in colon adenocarcinoma cells. Importantly, colon cancer cells cultured in the presence of TNF-α (10 ng/ml), demonstrated a sharp decrease in E-cadherin expression and an increase in vimentin expression (versus control cells). Interestingly, TNF-α treatment also upregulated (and delocalized) claudin-1 expression in a time-dependent manner accompanied by increase in proliferation and wound healing. Furthermore, similar to our previous observation that claudin-1 overexpression in CRC cells induces ERK1/2 and Src- activation, signaling associated with colon cancer cell survival and transformation, TNF-α-treatment induced upregulation of phospho-ERK1/2 and -Src expression. The shRNA-mediated inhibition of claudin-1 expression largely abrogated the TNF-α-induced changes in EMT, proliferation, migration, p-Erk and p-Src expression. Taken together, our data demonstrate TNF-α mediated regulation of claudin-1 and tumorigenic abilities of colon cancer cells and highlights a key role of deregulated claudin-1 expression in inflammation-induced colorectal cancer growth and progression, through the regulation of the ERK and Src-signaling.

  7. Claudin-1 promotes TNF-α-induced epithelial-mesenchymal transition and migration in colorectal adenocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, Ajaz A. [Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Ahmad, Rizwan; Uppada, SrijayaPrakash B. [Departments of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Singh, Amar B. [From the Department of Veterans Affairs, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Departments of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Dhawan, Punita, E-mail: punita.dhawan@unmc.edu [From the Department of Veterans Affairs, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Departments of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68022 (United States); Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68022 (United States)

    2016-11-15

    Epithelial-mesenchymal transition (EMT) is an important mechanism in cancer progression and malignancy including colorectal cancer (CRC). Importantly, inflammatory mediators are critical constituents of the local tumor environment and an intimate link between CRC progression and inflammation is now validated. We and others have reported key role of the deregulated claudin-1 expression in colon carcinogenesis including colitis-associated colon cancer (CAC). However, the causal association between claudin-1 expression and inflammation-induced colon cancer progression remains unclear. Here we demonstrate, TNF-α, a pro-inflammatory cytokine, regulates claudin-1 to modulate epithelial to mesenchymal transition (EMT) and migration in colon adenocarcinoma cells. Importantly, colon cancer cells cultured in the presence of TNF-α (10 ng/ml), demonstrated a sharp decrease in E-cadherin expression and an increase in vimentin expression (versus control cells). Interestingly, TNF-α treatment also upregulated (and delocalized) claudin-1 expression in a time-dependent manner accompanied by increase in proliferation and wound healing. Furthermore, similar to our previous observation that claudin-1 overexpression in CRC cells induces ERK1/2 and Src- activation, signaling associated with colon cancer cell survival and transformation, TNF-α-treatment induced upregulation of phospho-ERK1/2 and -Src expression. The shRNA-mediated inhibition of claudin-1 expression largely abrogated the TNF-α-induced changes in EMT, proliferation, migration, p-Erk and p-Src expression. Taken together, our data demonstrate TNF-α mediated regulation of claudin-1 and tumorigenic abilities of colon cancer cells and highlights a key role of deregulated claudin-1 expression in inflammation-induced colorectal cancer growth and progression, through the regulation of the ERK and Src-signaling.

  8. Epithelial-to-mesenchymal transition (EMT) induced by inflammatory priming elicits mesenchymal stromal cell-like immune-modulatory properties in cancer cells.

    Science.gov (United States)

    Ricciardi, M; Zanotto, M; Malpeli, G; Bassi, G; Perbellini, O; Chilosi, M; Bifari, F; Krampera, M

    2015-03-17

    Epithelial-to-mesenchymal transition (EMT) has a central role in cancer progression and metastatic dissemination and may be induced by local inflammation. We asked whether the inflammation-induced acquisition of mesenchymal phenotype by neoplastic epithelial cells is associated with the onset of mesenchymal stromal cell-like immune-regulatory properties that may enhance tumour immune escape. Cell lines of lung adenocarcinoma (A549), breast cancer (MCF7) and hepatocellular carcinoma (HepG2) were co-cultured with T, B and NK cells before and after EMT induction by either the supernatant of mixed-lymphocyte reactions or inflammatory cytokines. EMT occurrence following inflammatory priming elicited multiple immune-regulatory effects in cancer cells resulting in NK and T-cell apoptosis, inhibition of lymphocyte proliferation and stimulation of regulatory T and B cells. Indoleamine 2,3-dioxygenase, but not Fas ligand pathway, was involved at least in part in these effects, as shown by the use of specific inhibitors. EMT induced by inflammatory stimuli confers to cancer cells some mesenchymal stromal cell-like immune-modulatory properties, which could be a cue for cancer progression and metastatic dissemination by favouring immune escape.

  9. Detecting viability transitions of umbilical cord mesenchymal stem cells by Raman micro-spectroscopy

    International Nuclear Information System (INIS)

    Bai, H; Chen, P; Fang, H; Lin, L; Tang, G Q; Mu, G G; Gong, W; Liu, Z P; Wu, H; Zhao, H; Han, Z C

    2011-01-01

    Recent research suggests that human umbilical cord derived mesenchymal stem cells (hUC-MSCs) can be promising candidates for cell-based therapy. Since large population and high viability are generally required, detecting viability transitions of these cells is crucial for their population expansion and quality control. Here, as a non-invasive method, Raman micro-spectroscopy is applied to examine hUC-MSCs with different viability. Using peak fitting and statistic t-test, the Raman peaks with obvious differences between the cells with high viability (> 90%) and low viability ( -1 , symmetric stretching of C–C in lipids at 877 cm -1 and CH deformation in proteins at 1342 cm -1 show the most significant changes (p < 0.001). When the cell viability decreases, the intensities of the former two peaks are both about doubled while that of the latter peak reduces by about 30%. Based on these results, we propose that the viability of hUC-MSCs can be characterized by these three peaks. And their intensity changes can be understood from the model of excessive reactive oxygen species interacting with the bio-macromolecules

  10. Performance of the MFTF magnet cryogenic power leads

    International Nuclear Information System (INIS)

    VanSant, J.H.

    1983-01-01

    The cryogenic power lead system for the MFTF superconducting magnets has been acceptance tested and operated with the magnets. This system, which includes 5-m-long superconducting buses, 1.5-m-long vapor-cooled transition leads, external warm buses, and a cryostack, can conduct up to 6000 A (dc) and operate adiabatically for long periods. We present both design details and performance data; our MFTF version is an example of a reliable lead system for large superconducting magnets contained in a much larger vacuum vessel

  11. Cell surface glycan alterations in epithelial mesenchymal transition process of Huh7 hepatocellular carcinoma cell.

    Directory of Open Access Journals (Sweden)

    Shan Li

    Full Text Available BACKGROUND AND OBJECTIVE: Due to recurrence and metastasis, the mortality of Hepatocellular carcinoma (HCC is high. It is well known that the epithelial mesenchymal transition (EMT and glycan of cell surface glycoproteins play pivotal roles in tumor metastasis. The goal of this study was to identify HCC metastasis related differential glycan pattern and their enzymatic basis using a HGF induced EMT model. METHODOLOGY: HGF was used to induce HCC EMT model. Lectin microarray was used to detect the expression of cell surface glycan and the difference was validated by lectin blot and fluorescence cell lectin-immunochemistry. The mRNA expression levels of glycotransferases were determined by qRT-PCR. RESULTS: After HGF treatment, the Huh7 cell lost epithelial characteristics and obtained mesenchymal markers. These changes demonstrated that HGF could induce a typical cell model of EMT. Lectin microarray analysis identified a decreased affinity in seven lectins ACL, BPL, JAC, MPL, PHA-E, SNA, and SBA to the glycan of cell surface glycoproteins. This implied that glycan containing T/Tn-antigen, NA2 and bisecting GlcNAc, Siaα2-6Gal/GalNAc, terminal α or βGalNAc structures were reduced. The binding ability of thirteen lectins, AAL, LCA, LTL, ConA, NML, NPL, DBA, HAL, PTL II, WFL, ECL, GSL II and PHA-L to glycan were elevated, and a definite indication that glycan containing terminal αFuc and ± Sia-Le, core fucose, α-man, gal-β(α GalNAc, β1,6 GlcNAc branching and tetraantennary complex oligosaccharides structures were increased. These results were further validated by lectin blot and fluorescence cell lectin-immunochemistry. Furthermore, the mRNA expression level of Mgat3 decreased while that of Mgat5, FucT8 and β3GalT5 increased. Therefore, cell surface glycan alterations in the EMT process may coincide with the expression of glycosyltransferase. CONCLUSIONS: The findings of this study systematically clarify the alterations of cell surface

  12. Mitigation potential of greenhouse gas emission and implications on fuel consumption due to clean energy vehicles as public passenger transport in Kathmandu Valley of Nepal: A case study of trolley buses in Ring Road

    International Nuclear Information System (INIS)

    Pradhan, Shreekar; Ale, Bhakta Bahadur; Amatya, Vishwa Bhusan

    2006-01-01

    This paper estimates the consequences in fuel consumption and greenhouse gas emission due to the possible intervention of the electric run trolley buses in the existing public transport system in a particular road up to the year 2025 in Kathmandu Valley. It projects the scenarios on the basis that the passenger travel demand is the function of population and income. Basically, it uses the Long Range Energy Alternatives Planning System software to develop Business as Usual scenario and the five alternative scenarios. The alternative scenarios are 100% replacement of vehicles catering to mass-transit in the concerned routes, 50% replacement, 25% replacement, stopping future growth of other vehicles catering to mass-transit in the concerned routes and 25% replacement in the first year, and combination scenarios. The results estimate that the passenger travel demand will increase by three folds from the year 2003 to the year 2025. It projects the three-fold increase of the existing vehicle activity by the year 2025 in Business as Usual scenario. The fuel consumption will increase by 2.4 times compared to the year 2003. It estimates the total greenhouse gas (GHG) emission as 8.5 thousands tons in year 2003 which will increase by more than 3 times in year 2025. It estimates that 174.3 thousands t CO 2 e can be avoided in combination scenario. The paper concludes that the intervention of clean energy transport in the existing public transport can have a significant positive impact on the GHG emission and current fuel consumption

  13. 76 FR 68819 - State of Good Repair Bus and Bus Facilities Discretionary Program Funds

    Science.gov (United States)

    2011-11-07

    ... Availability on June 24, 2011. The SGR Initiative makes funds available to public transit providers to finance capital projects to replace, rehabilitate, and purchase buses and related equipment and to construct bus...

  14. PEM fuel cells thermal and water management fundamentals

    CERN Document Server

    Wang, Yun; Cho, Sung Chan

    2014-01-01

    Polymer Electrolyte Membrane (PEM) fuel cells convert chemical energy in hydrogen into electrical energy with water as the only by-product. Thus, PEM fuel cells hold great promise to reduce both pollutant emissions and dependency on fossil fuels, especially for transportation-passenger cars, utility vehicles, and buses-and small-scale stationary and portable power generators. But one of the greatest challenges to realizing the high efficiency and zero emissions potential of PEM fuel cells technology is heat and water management. This book provides an introduction to the essential concepts for effective thermal and water management in PEM fuel cells and an assessment on the current status of fundamental research in this field. The book offers you: An overview of current energy and environmental challenges and their imperatives for the development of renewable energy resources, including discussion of the role of PEM fuel cells in addressing these issues; Reviews of basic principles pertaining to PEM fuel cel...

  15. Detection of Thyroid Metastasis pf Renal Transitional Cell Carcinoma Using FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Il; Kim, Yu Kyeong; Kim, Sang Eun [Seoul National Univ. Bundang Hospital, Seoul (Korea, Republic of); Lee, Jong Jin [Univ. of Ulsan College of Medicine, Seoul (Korea, Republic of); Paik, Jin Ho [Seoul National Univ. Bundang Hospital, Seoul (Korea, Republic of)

    2011-06-15

    A 69 year old man who was diagnosed with renal transitional cell carcinoma (TCC) underwent F 18 fluorodeoxyglucose (FDG) positron emission tomography with computed tomography (PET/CT) for detecting recurrence after chemotherapy. FDG PET/CT revealed multiple new hypermetabolic lesions in many places, including the right thyroid gland. Biopsy of the thyroid lesion was performed,and a diagnosis of metastatic TCC was made. We could detect thyroid metastasis of renal TCC by FDG PET/CT.

  16. Florida DOT Orlando ITS World Congress Vehicle Awareness Device

    Data.gov (United States)

    Department of Transportation — Florida DOT (FDOT) installed Vehicle Awareness Devices (VADs) on a set of Lynx transit buses as part of a demonstration for the ITS World Congress held in Orlando in...

  17. FRK inhibits breast cancer cell migration and invasion by suppressing epithelial-mesenchymal transition.

    Science.gov (United States)

    Ogunbolude, Yetunde; Dai, Chenlu; Bagu, Edward T; Goel, Raghuveera Kumar; Miah, Sayem; MacAusland-Berg, Joshua; Ng, Chi Ying; Chibbar, Rajni; Napper, Scott; Raptis, Leda; Vizeacoumar, Frederick; Vizeacoumar, Franco; Bonham, Keith; Lukong, Kiven Erique

    2017-12-22

    The human fyn-related kinase (FRK) is a non-receptor tyrosine kinase known to have tumor suppressor activity in breast cancer cells. However, its mechanism of action has not been fully characterized. We generated FRK-stable MDA-MB-231 breast cancer cell lines and analyzed the effect on cell proliferation, migration, and invasiveness. We also used kinome analysis to identify potential FRK-regulated signaling pathways. We employed both immunoblotting and RT-PCR to identify/validate FRK-regulated targets (proteins and genes) in these cells. Finally, we interrogated the TCGA and GENT gene expression databases to determine the correlation between the expression of FRK and epithelial/mesenchymal markers. We observed that FRK overexpression suppressed cell proliferation, migration, and invasiveness, inhibited various JAK/STAT, MAPK and Akt signaling pathways, and suppressed the expression of some STAT3 target genes. Also, FRK overexpression increased the expression of epithelial markers including E-cadherin mRNA and down-regulated the transcript levels of vimentin, fibronectin, and slug. Finally, we observed an inverse correlation between FRK expression and mesenchymal markers in a large cohort of breast cancer cells. Our data, therefore, suggests that FRK represses cell proliferation, migration and invasiveness by suppressing epithelial to mesenchymal transition.

  18. Staphylococcus aureus-induced G2/M phase transition delay in host epithelial cells increases bacterial infective efficiency.

    Directory of Open Access Journals (Sweden)

    Ludmila Alekseeva

    Full Text Available Staphylococcus aureus is a highly versatile, opportunistic pathogen and the etiological agent of a wide range of infections in humans and warm-blooded animals. The epithelial surface is its principal site of colonization and infection. In this work, we investigated the cytopathic effect of S. aureus strains from human and animal origins and their ability to affect the host cell cycle in human HeLa and bovine MAC-T epithelial cell lines. S. aureus invasion slowed down cell proliferation and induced a cytopathic effect, resulting in the enlargement of host cells. A dramatic decrease in the number of mitotic cells was observed in the infected cultures. Flow cytometry analysis revealed an S. aureus-induced delay in the G2/M phase transition in synchronous HeLa cells. This delay required the presence of live S. aureus since the addition of the heat-killed bacteria did not alter the cell cycle. The results of Western blot experiments showed that the G2/M transition delay was associated with the accumulation of inactive cyclin-dependent kinase Cdk1, a key inducer of mitosis entry, and with the accumulation of unphosphorylated histone H3, which was correlated with a reduction of the mitotic cell number. Analysis of S. aureus proliferation in asynchronous, G1- and G2-phase-enriched HeLa cells showed that the G2 phase was preferential for bacterial infective efficiency, suggesting that the G2 phase delay may be used by S. aureus for propagation within the host. Taken together, our results divulge the potential of S. aureus in the subversion of key cellular processes such as cell cycle progression, and shed light on the biological significance of S. aureus-induced host cell cycle alteration.

  19. The nested variant of bladder transitional cell carcinoma: Review of 12 cases and review of the literature.

    Science.gov (United States)

    Carrion-Ballardo, C J; Gala-Solana, L; Portillo-Martin, J A; Azueta-Etxebarria, A; Truan-Cacho, D; Campos-Juanatey, F

    2015-01-01

    The nested variant of bladder transitional cell carcinoma is extremely rare and has a different biological behavior to other bladder tumors. The aim of this study is to analize if their behavior is as aggressive as has been described in the literature. Review of 12 diagnosed cases with nested variant of bladder transitional cell carcinoma and analysis of demographic characteristics, clinical presentation, tumor characteristics, treatment options, analysis of recurrence and cancer-specific survival between January 1997 and December 2010 in our hospital. 50% of the cases had a pathologic stage ≥T2, with grade of differentiation G2 (50%) or G3 (50%). After the pathological result of the TUR (transurethral resection) Bladder, 5 cases underwent radical cystoprostatectomy, 3 a second TUR bladder and 4 cases with treatment chemotherapy and/or radiotherapy (RT). Five out of 12 cases (41.7%) died due to bladder cancer and 3 died (25%) of other causes (urinary sepsis, respiratory failure, renal failure). With a median follow up of 40 months, the overall survival was 50% and cancer-specific survival of 65.6%. The nested variant of bladder transitional cell carcinoma is a disease with an advanced-stage presentation, with high recurrence and mortality rates despite the use of different treatments. So far there is not a clinical practice guideline for this variety of urothelial tumor. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Fuzheng Huayu Recipe Ameliorates Liver Fibrosis by Restoring Balance between Epithelial-to-Mesenchymal Transition and Mesenchymal-to-Epithelial Transition in Hepatic Stellate Cells

    Directory of Open Access Journals (Sweden)

    Qin Pan

    2015-01-01

    Full Text Available Activation of hepatic stellate cells (HSCs depending on epithelial-to-mesenchymal transition (EMT reflects the key event of liver fibrosis. Contrastively, mesenchymal-to-epithelial transition (MET of HSCs facilitates the fibrosis resolution. Here we investigated the effect of Fuzheng Huayu (FZHY recipe, a Chinese herbal decoction made of Radix Salviae Miltiorrhizae, Semen Persicae, Cordyceps sinensis, Pollen Pini, and Gynostemma pentaphyllum, on liver fibrosis concerning the balance of EMT and MET in HSCs. In contrast to the increased TGF-β1/BMP-7 ratio in activated HSCs, FZHY administration induced significant upregulation of BMP-7 and downregulation of TGF-β1 at both transcription and translation levels. Restoration of TGF-β1/BMP-7 ratio inhibited the expression of p38 MAPK and phosphorylated p38 MAPK, resulting in the reversal of epithelial-to-mesenchymal transition (EMT to mesenchymal-to-epithelial transition (MET as characterized by the abolishment of EMT markers (α-SMA and desmin and reoccurrence of MET marker (E-cadherin. In vivo treatment of FZHY recipe also demonstrated the statistical reduction of activated HSCs with EMT phenotype, which attenuated the carbon tetrachloride- (CCl4- induced liver fibrosis in a dose-dependent manner. These findings may highlight a novel antifibrotic role of FZHY recipe on the basis of rebalancing EMT and MET in HSCs.

  1. Factors related to recurrence of bladder transitional cell carcinoma after transurethral resection of bladder tumor (TUR-BT)

    International Nuclear Information System (INIS)

    Nam, Ki Dong; Koo, Bong Sik; Yoon, Seong Kuk; Park, Byung Ho; Nam, Kyung Jin; Choi, Jong Cheol; Lee, Ki Nam; Lee, Young Il; Chung, Duck Hwan

    1998-01-01

    The purpose of this study is to evaluate factors related to the recurrence of TCC (transitional cell carcinoma) in the urinary bladder after transurethal resection of bladder tumor (TUR-BT). We retrospectively reviewed 54 patients in whom TCC (transitional cell carcinoma) after TUR-BT had been confirmed. Recurrence was evaluated by US, CT, cystoscopy and urine smear during the follow-up period of 6 months. The multiplicity, shape, size, and calcification of TCC, as revealed by radiologic studies, were evaluated retrospectively before TUR-BT. After TUR-BT, the histologic grade and pathologic stage of TCC were evaluated. Radiologically, multiple and/or sessile type TCC had a higher recurrence rate than the single and/or pedunculated type. Pathologically, when the grade and stage of bladder tumor were higher, recurrent rates were higher. (author). 17 refs., 3 tabs., 3 figs

  2. Loss of γ-cytoplasmic actin triggers myofibroblast transition of human epithelial cells.

    Science.gov (United States)

    Lechuga, Susana; Baranwal, Somesh; Li, Chao; Naydenov, Nayden G; Kuemmerle, John F; Dugina, Vera; Chaponnier, Christine; Ivanov, Andrei I

    2014-10-15

    Transdifferentiation of epithelial cells into mesenchymal cells and myofibroblasts plays an important role in tumor progression and tissue fibrosis. Such epithelial plasticity is accompanied by dramatic reorganizations of the actin cytoskeleton, although mechanisms underlying cytoskeletal effects on epithelial transdifferentiation remain poorly understood. In the present study, we observed that selective siRNA-mediated knockdown of γ-cytoplasmic actin (γ-CYA), but not β-cytoplasmic actin, induced epithelial-to-myofibroblast transition (EMyT) of different epithelial cells. The EMyT manifested by increased expression of α-smooth muscle actin and other contractile proteins, along with inhibition of genes responsible for cell proliferation. Induction of EMyT in γ-CYA-depleted cells depended on activation of serum response factor and its cofactors, myocardial-related transcriptional factors A and B. Loss of γ-CYA stimulated formin-mediated actin polymerization and activation of Rho GTPase, which appear to be essential for EMyT induction. Our findings demonstrate a previously unanticipated, unique role of γ-CYA in regulating epithelial phenotype and suppression of EMyT that may be essential for cell differentiation and tissue fibrosis. © 2014 Lechuga, Baranwal, et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  3. Normal endometrial stromal cells regulate 17β-estradiol-induced epithelial-mesenchymal transition via slug and E-cadherin in endometrial adenocarcinoma cells in vitro.

    Science.gov (United States)

    Zhang, Hui; Li, Hongyan; Qi, Shasha; Liu, Zhao; Fu, Yibing; Li, Mingjiang; Zhao, Xingbo

    2017-01-01

    Stroma-tumor communication participates in the pathogenesis of endometrial carcinomas. In previous studies, we found that normal stromal cells inhibited the growth of endometrial carcinoma cells. Here, we investigated the role of normal stromal cells in the epithelial-mesenchymal transition (EMT) of endometrial carcinoma cells and explored the possible mechanism implied. We found that conditioned medium (CM) by normal endometrial stromal cells (NSC) reduced cell growth and induced cell apoptosis in Ishikawa cells. CM by NSC inhibited 17β-estradiol-induced cell growth and apoptosis decrease in Ishikawa cells. Moreover, CM by NSC inhibited the migration and invasion, and 17β-estradiol-induced migration and invasion in Ishikawa cells. Meanwhile, CM by NSC decreased Slug expression and 17β-estradiol-induced Slug expression, increased E-cadherin expression and abolished 17β-estradiol-induced E-cadherin reduction in Ishikawa cells. In conclusion, normal stromal factors can inhibit 17β-estradiol-induced cell proliferation and apoptosis inhibition, and abolished 17β-estradiol-induced EMT in endometrial cancer cell via regulating E-cadherin and Slug expression.

  4. Interaction of Wnt Signaling with BMP/Smad Signaling during the Transition from Cell Proliferation to Myogenic Differentiation in Mouse Myoblast-Derived Cells

    Directory of Open Access Journals (Sweden)

    Kumiko Terada

    2013-01-01

    Full Text Available Background. Wnt signaling is involved in muscle formation through β-catenin-dependent or -independent pathways, but interactions with other signaling pathways including transforming growth factor β/Smad have not been precisely elucidated. Results. As Wnt4 stimulates myogenic differentiation by antagonizing myostatin (GDF8 activity, we examined the role of Wnt4 signaling during muscle differentiation in the C2C12 myoblast cell line. Among several extrinsic signaling molecules examined in a microarray analysis of C2C12 cells during the transition from cell proliferation to differentiation after mitogen deprivation, bone morphogenetic protein 4 (BMP4 expression was prominently increased. Wnt4 overexpression had similar effects on BMP4 expression. BMP4 was able to inhibit muscle differentiation when added to the culture medium. BMP4 and noggin had no effects on the cellular localization of β-catenin induced by Wnt3a; however, the BMP4-induced phosphorylation of Smad1/5/8 was enhanced by Wnt4, but not by Wnt3a. The BMP antagonist noggin effectively stimulated muscle differentiation through binding to endogenous BMPs, and the effect of noggin was enhanced by the presence of Wnt3a and Wnt4. Conclusion. These results suggest that BMP/Smad pathways are modified through Wnt signaling during the transition from progenitor cell proliferation to myogenic differentiation, although Wnt/β-catenin signaling is not modified with BMP/Smad signaling.

  5. MicroRNA Cluster miR-17-92 Regulates Neural Stem Cell Expansion and Transition to Intermediate Progenitors in the Developing Mouse Neocortex

    Directory of Open Access Journals (Sweden)

    Shan Bian

    2013-05-01

    Full Text Available During development of the embryonic neocortex, tightly regulated expansion of neural stem cells (NSCs and their transition to intermediate progenitors (IPs are critical for normal cortical formation and function. Molecular mechanisms that regulate NSC expansion and transition remain unclear. Here, we demonstrate that the microRNA (miRNA miR-17-92 cluster is required for maintaining proper populations of cortical radial glial cells (RGCs and IPs through repression of Pten and Tbr2 protein. Knockout of miR-17-92 and its paralogs specifically in the developing neocortex restricts NSC proliferation, suppresses RGC expansion, and promotes transition of RGCs to IPs. Moreover, Pten and Tbr2 protectors specifically block silencing activities of endogenous miR-17-92 and control proper numbers of RGCs and IPs in vivo. Our results demonstrate a critical role for miRNAs in promoting NSC proliferation and modulating the cell-fate decision of generating distinct neural progenitors in the developing neocortex.

  6. Motility-driven glass and jamming transitions in biological tissues

    Science.gov (United States)

    Bi, Dapeng; Yang, Xingbo; Marchetti, M. Cristina; Manning, M. Lisa

    2017-01-01

    Cell motion inside dense tissues governs many biological processes, including embryonic development and cancer metastasis, and recent experiments suggest that these tissues exhibit collective glassy behavior. To make quantitative predictions about glass transitions in tissues, we study a self-propelled Voronoi (SPV) model that simultaneously captures polarized cell motility and multi-body cell-cell interactions in a confluent tissue, where there are no gaps between cells. We demonstrate that the model exhibits a jamming transition from a solid-like state to a fluid-like state that is controlled by three parameters: the single-cell motile speed, the persistence time of single-cell tracks, and a target shape index that characterizes the competition between cell-cell adhesion and cortical tension. In contrast to traditional particulate glasses, we are able to identify an experimentally accessible structural order parameter that specifies the entire jamming surface as a function of model parameters. We demonstrate that a continuum Soft Glassy Rheology model precisely captures this transition in the limit of small persistence times, and explain how it fails in the limit of large persistence times. These results provide a framework for understanding the collective solid-to-liquid transitions that have been observed in embryonic development and cancer progression, which may be associated with Epithelial-to-Mesenchymal transition in these tissues. PMID:28966874

  7. Epithelial-to-Mesenchymal Transition in Pancreatic Ductal Adenocarcinoma and Pancreatic Tumor Cell Lines: The Role of Neutrophils and Neutrophil-Derived Elastase

    Directory of Open Access Journals (Sweden)

    Thomas Große-Steffen

    2012-01-01

    Full Text Available Pancreatic ductal adenocarcinoma (PDAC is frequently associated with fibrosis and a prominent inflammatory infiltrate in the desmoplastic stroma. Moreover, in PDAC, an epithelial-to-mesenchymal transition (EMT is observed. To explore a possible connection between the infiltrating cells, particularly the polymorphonuclear neutrophils (PMN and the tumor cell transition, biopsies of patients with PDAC (n=115 were analysed with regard to PMN infiltration and nuclear expression of β-catenin and of ZEB1, well-established indicators of EMT. In biopsies with a dense PMN infiltrate, a nuclear accumulation of β-catenin and of ZEB1 was observed. To address the question whether PMN could induce EMT, they were isolated from healthy donors and were cocultivated with pancreatic tumor cells grown as monolayers. Rapid dyshesion of the tumor cells was seen, most likely due to an elastase-mediated degradation of E-cadherin. In parallel, the transcription factor TWIST was upregulated, β-catenin translocated into the nucleus, ZEB1 appeared in the nucleus, and keratins were downregulated. EMT was also induced when the tumor cells were grown under conditions preventing attachment to the culture plates. Here, also in the absence of elastase, E-cadherin was downmodulated. PMN as well as prevention of adhesion induced EMT also in liver cancer cell line. In conclusion, PMN via elastase induce EMT in vitro, most likely due to the loss of cell-to-cell contact. Because in pancreatic cancers the transition to a mesenchymal phenotype coincides with the PMN infiltrate, a contribution of the inflammatory response to the induction of EMT and—by implication—to tumor progression is possible.

  8. EST! best practices

    Science.gov (United States)

    2000-10-05

    This booklet presents the eighteen winners in a competition for projects that promote environmentally sustainable transportation (EST). These range from car sharing to hydrogen fueled buses to public transit promotion campaign. Each project is presen...

  9. Fuel cell bus operation, system investigation H2 bus

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The WP covers two tasks: - Prepartion of Technical Catalogue: In cooperation with ICIL, AR have compiled a technical catalogue, providing the impartial descriptions, both of existing technology and regulations, and the likely future developments of these, as to remedy the first problem faced by a potential hydrogen bus fleet operator viz the absence of an impartial description of the available vehicle and fuels systems together with the absence of a description of regulatory and safety factors which need consideration. - Fuel Cell Bus Operation - System Investigation H 2 Bus: The application of fuel cell electric generation systems to hybrid electrical buses or electrical busses without any storage system on board is considered. The task will cover safety and environmental aspects, a cost estimate and a market evaluation. (orig.)

  10. A core invasiveness gene signature reflects epithelial-to-mesenchymal transition but not metastatic potential in breast cancer cell lines and tissue samples.

    Directory of Open Access Journals (Sweden)

    Melike Marsan

    Full Text Available INTRODUCTION: Metastases remain the primary cause of cancer-related death. The acquisition of invasive tumour cell behaviour is thought to be a cornerstone of the metastatic cascade. Therefore, gene signatures related to invasiveness could aid in stratifying patients according to their prognostic profile. In the present study we aimed at identifying an invasiveness gene signature and investigated its biological relevance in breast cancer. METHODS & RESULTS: We collected a set of published gene signatures related to cell motility and invasion. Using this collection, we identified 16 genes that were represented at a higher frequency than observed by coincidence, hereafter named the core invasiveness gene signature. Principal component analysis showed that these overrepresented genes were able to segregate invasive and non-invasive breast cancer cell lines, outperforming sets of 16 randomly selected genes (all P<0.001. When applied onto additional data sets, the expression of the core invasiveness gene signature was significantly elevated in cell lines forced to undergo epithelial-mesenchymal transition. The link between core invasiveness gene expression and epithelial-mesenchymal transition was also confirmed in a dataset consisting of 2420 human breast cancer samples. Univariate and multivariate Cox regression analysis demonstrated that CIG expression is not associated with a shorter distant metastasis free survival interval (HR = 0.956, 95%C.I. = 0.896-1.019, P = 0.186. DISCUSSION: These data demonstrate that we have identified a set of core invasiveness genes, the expression of which is associated with epithelial-mesenchymal transition in breast cancer cell lines and in human tissue samples. Despite the connection between epithelial-mesenchymal transition and invasive tumour cell behaviour, we were unable to demonstrate a link between the core invasiveness gene signature and enhanced metastatic potential.

  11. Selective arterial embolization for control of haematuria secondary to advanced or recurrent transitional cell carcinoma of the bladder.

    LENUS (Irish Health Repository)

    Halpenny, D

    2014-05-02

    Haematuria is a common symptom in patients with advanced transitional cell carcinoma of the bladder. We report our experience of selective pelvic embolization using gelfoam as an embolic agent to treat intractable haematuria in these patients.

  12. A small population of liver endothelial cells undergoes endothelial-to-mesenchymal transition in response to chronic liver injury.

    Science.gov (United States)

    Ribera, Jordi; Pauta, Montse; Melgar-Lesmes, Pedro; Córdoba, Bernat; Bosch, Anna; Calvo, Maria; Rodrigo-Torres, Daniel; Sancho-Bru, Pau; Mira, Aurea; Jiménez, Wladimiro; Morales-Ruiz, Manuel

    2017-11-01

    Rising evidence points to endothelial-to-mesenchymal transition (EndMT) as a significant source of the mesenchymal cell population in fibrotic diseases. In this context, we hypothesized that liver endothelial cells undergo EndMT during fibrosis progression. Cirrhosis in mice was induced by CCl 4 A transgenic mouse expressing a red fluorescent protein reporter under the control of Tie2 promoter (Tie2-tdTomato) was used to trace the acquisition of EndMT. Sinusoidal vascular connectivity was evaluated by intravital microscopy and high-resolution three-dimensional confocal microscopy. A modest but significant fraction of liver endothelial cells from both cirrhotic patients and CCl 4 -treated Tie2-tdTomato mice acquired an EndMT phenotype characterized by the coexpression of CD31 and α-smooth muscle actin, compared with noncirrhotic livers. Bone morphogenetic protein-7 (BMP-7) inhibited the acquisition of EndMT induced by transforming growth factor-β1 (TGF-β1) treatment in cultured primary mouse liver endothelial cells from control mice. EndMT was also reduced significantly in vivo in cirrhotic Tie2-tdTomato mice treated intraperitoneally with BMP-7 compared with untreated mice (1.9 ± 0.2 vs. 3.8 ± 0.3%, respectively; P livers correlated with a significant decrease in liver fibrosis ( P livers in both animal models and patients. BMP-7 treatment decreases the occurrence of the EndMT phenotype and has a positive impact on the severity of disease by reducing fibrosis and sinusoidal vascular disorganization. NEW & NOTEWORTHY A subpopulation of liver endothelial cells from cirrhotic patients and mice with liver fibrosis undergoes endothelial-to-mesenchymal transition. Liver endothelial cells from healthy mice could transition into a mesenchymal phenotype in culture in response to TGF-β1 treatment. Fibrotic livers treated chronically with BMP-7 showed lower EndMT acquisition, reduced fibrosis, and improved vascular organization. Copyright © 2017 the American

  13. Cytological diagnosis of a rare case of cutaneous metastasis from transitional cell carcinoma, renal pelvis

    Directory of Open Access Journals (Sweden)

    Pragya Singh

    2017-12-01

    Full Text Available Transitional cell carcinoma (TCC arising from renal pelvis rarely gives rise to cutaneous metastasis. Due to the insufficient literature, the exact incidence is not known till date. Moreover, the diagnosis is confirmed on histopathological examination with the aid of immunohistochemistry wherever needed. We are presenting a case of a 70-year-old female with metastatic TCC from the renal pelvis to the abdominal skin, which was diagnosed on cytology alone along with the cell block preparation. We also highlight the important cytomorphological and immunohistochemical features noted, which need to be known to avoid any diagnostic delay.

  14. Salinomycin induces cell death and differentiation in head and neck squamous cell carcinoma stem cells despite activation of epithelial-mesenchymal transition and Akt

    International Nuclear Information System (INIS)

    Kuo, Selena Z; Blair, Katherine J; Rahimy, Elham; Kiang, Alan; Abhold, Eric; Fan, Jian-Bing; Wang-Rodriguez, Jessica; Altuna, Xabier; Ongkeko, Weg M

    2012-01-01

    Cancer stem cells (CSC) are believed to play a crucial role in cancer recurrence due to their resistance to conventional chemotherapy and capacity for self-renewal. Recent studies have reported that salinomycin, a livestock antibiotic, selectively targets breast cancer stem cells 100-fold more effectively than paclitaxel. In our study we sought to determine the effects of salinomycin on head and neck squamous cell carcinoma (HNSCC) stem cells. MTS and TUNEL assays were used to study cell proliferation and apoptosis as a function of salinomycin exposure in JLO-1, a putative HNSCC stem cell culture. MTS and trypan blue dye exclusion assays were performed to investigate potential drug interactions between salinomycin and cisplatin or paclitaxel. Stem cell-like phenotype was measured by mRNA expression of stem cell markers, sphere-forming capacity, and matrigel invasion assays. Immunoblotting was also used to determine expression of epithelial-mesenchymal transition (EMT) markers and Akt phosphorylation. Arrays by Illumina, Inc. were used to profile microRNA expression as a function of salinomycin dose. In putative HNSCC stem cells, salinomycin was found to significantly inhibit cell viability, induce a 71.5% increase in levels of apoptosis, elevate the Bax/Bcl-2 ratio, and work synergistically with cisplatin and paclitaxel in inducing cell death. It was observed that salinomycin significantly inhibited sphere forming-capability and repressed the expression of CD44 and BMI-1 by 3.2-fold and 6.2-fold, respectively. Furthermore, salinomycin reduced invasion of HNSCC stem cells by 2.1 fold. Contrary to expectations, salinomycin induced the expression of EMT markers Snail, vimentin, and Zeb-1, decreased expression of E-cadherin, and also induced phosphorylation of Akt and its downstream targets GSK3-β and mTOR. These results demonstrate that in HNSCC cancer stem cells, salinomycin can cause cell death and decrease stem cell properties despite activation of both EMT and

  15. Flocking Transition in Confluent Tissues

    Science.gov (United States)

    Paoluzzi, Matteo; Giavazzi, Fabio; Macchi, Marta; Scita, Giorgio; Cerbino, Roberto; Manning, Lisa; Marchetti, Cristina

    The emerging of collective migration in biological tissues plays a pivotal role in embryonic morphogenesis, wound healing and cancer invasion. While many aspects of single cell movements are well established, the mechanisms leading to coherent displacements of cohesive cell groups are still poorly understood. Some of us recently proposed a Self-Propelled Voronoi (SPV) model of dense tissues that combines self-propelled particle models and vertex models of confluent cell layers and exhibits a liquid-solid transition as a function of cell shape and cell motility. We now examine the role of cell polarization on collective cell dynamics by introducing an orientation mechanism that aligns cell polarization with local cell motility. The model predicts a density-independent flocking transition tuned by the strength of the aligning interaction, with both solid and liquid flocking states existing in different regions of parameter space. MP and MCM were supported by the Simons Foundation Targeted Grant in the Mathematical Modeling of Living Systems Number: 342354 and by the Syracuse Soft Matter Program.

  16. Connective tissue growth factor activates pluripotency genes and mesenchymal-epithelial transition in head and neck cancer cells.

    Science.gov (United States)

    Chang, Cheng-Chi; Hsu, Wen-Hao; Wang, Chen-Chien; Chou, Chun-Hung; Kuo, Mark Yen-Ping; Lin, Been-Ren; Chen, Szu-Ta; Tai, Shyh-Kuan; Kuo, Min-Liang; Yang, Muh-Hwa

    2013-07-01

    The epithelial-mesenchymal transition (EMT) is a key mechanism in both embryonic development and cancer metastasis. The EMT introduces stem-like properties to cancer cells. However, during somatic cell reprogramming, mesenchymal-epithelial transition (MET), the reverse process of EMT, is a crucial step toward pluripotency. Connective tissue growth factor (CTGF) is a multifunctional secreted protein that acts as either an oncoprotein or a tumor suppressor among different cancers. Here, we show that in head and neck squamous cell carcinoma (HNSCC), CTGF promotes the MET and reduces invasiveness. Moreover, we found that CTGF enhances the stem-like properties of HNSCC cells and increases the expression of multiple pluripotency genes. Mechanistic studies showed that CTGF induces c-Jun expression through αvβ3 integrin and that c-Jun directly activates the transcription of the pluripotency genes NANOG, SOX2, and POU5F1. Knockdown of CTGF in TW2.6 cells was shown to reduce tumor formation and attenuate E-cadherin expression in xenotransplanted tumors. In HNSCC patient samples, CTGF expression was positively correlated with the levels of CDH1, NANOG, SOX2, and POU5F1. Coexpression of CTGF and the pluripotency genes was found to be associated with a worse prognosis. These findings are valuable in elucidating the interplay between epithelial plasticity and stem-like properties during cancer progression and provide useful information for developing a novel classification system and therapeutic strategies for HNSCC. ©2013 AACR.

  17. Texas Hydrogen Highway Fuel Cell Hybrid Bus and Fueling Infrastructure Technology Showcase - Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Hitchcock, David

    2012-06-29

    , and regenerative braking for battery charging. It uses a 19.3 kW Ballard PEM fuel cell, will store 12.6 kg of hydrogen at 350 Bar, and includes a 60 kWh battery storage system. The objectives of the project included the following: (a) To advance commercialization of hydrogen-powered transit buses and supporting infrastructure; (b) To provide public outreach and education by showcasing the operation of a 22-foot fuel cell hybrid shuttle bus and Texas first hydrogen fueling infrastructure; and (c) To showcase operation of zero-emissions vehicle for potential transit applications. As mentioned above, the project successfully demonstrated an early vehicle technology, the Ebus plug-in hybrid fuel cell bus, and that success has led to the acquisition of a more advanced vehicle that can take advantage of the same fueling infrastructure. Needed hydrogen station improvements have been identified that will enhance the capabilities of the fueling infrastructure to serve the new bus and to meet the transit agency needs. Over the course of this project, public officials, local government staff, and transit operators were engaged in outreach and education activities that acquainted them with the real world operation of a fuel cell bus and fueling infrastructure. Transit staff members in the Dallas/Ft. Worth region were invited to a workshop in Arlington, Texas at the North Central Texas Council of Governments to participate in a workshop on hydrogen and fuel cells, and to see the fuel cell bus in operation. The bus was trucked to the meeting for this purpose so that participants could see and ride the bus. Austin area transit staff members visited the fueling site in Austin to be briefed on the bus and to participate in a fueling demonstration. This led to further meetings to determine how a fuel cell bus and fueling station could be deployed at Capital Metro Transit. Target urban regions that expressed additional interest during the project in response to the outreach meetings and

  18. Transition to turbulence

    International Nuclear Information System (INIS)

    Pomeau, Y.

    1981-07-01

    In this work it is reviewed a few known types of transition to turbulence, as the cascade of period doubling and the intermittent transition. This happens in dynamical systems with a few degrees of freedom, as modelled by the iteration of non linear maps. Then it is presented specific transitions for systems with many degrees of freedom. It is condidered first the occurence of a low frequency broadband noise in large cells at the onset of Rayleigh-Benard convection; then the transition by intermittent bursts in parallel flows. In this last case, one is concerned with localized and finite amplitude perturbations. Simple geometric arguments show that these fluctuations, when they are isolated and with a well definite relative speed, exist for a single value of the Reynolds number only [fr

  19. CXCL9 Regulates TGF-β1-Induced Epithelial to Mesenchymal Transition in Human Alveolar Epithelial Cells.

    Science.gov (United States)

    O'Beirne, Sarah L; Walsh, Sinead M; Fabre, Aurélie; Reviriego, Carlota; Worrell, Julie C; Counihan, Ian P; Lumsden, Robert V; Cramton-Barnes, Jennifer; Belperio, John A; Donnelly, Seamas C; Boylan, Denise; Marchal-Sommé, Joëlle; Kane, Rosemary; Keane, Michael P

    2015-09-15

    Epithelial to mesenchymal cell transition (EMT), whereby fully differentiated epithelial cells transition to a mesenchymal phenotype, has been implicated in the pathogenesis of idiopathic pulmonary fibrosis (IPF). CXCR3 and its ligands are recognized to play a protective role in pulmonary fibrosis. In this study, we investigated the presence and extent of EMT and CXCR3 expression in human IPF surgical lung biopsies and assessed whether CXCR3 and its ligand CXCL9 modulate EMT in alveolar epithelial cells. Coexpression of the epithelial marker thyroid transcription factor-1 and the mesenchymal marker α-smooth muscle actin and CXCR3 expression was examined by immunohistochemical staining of IPF surgical lung biopsies. Epithelial and mesenchymal marker expression was examined by quantitative real-time PCR, Western blotting, and immunofluorescence in human alveolar epithelial (A549) cells treated with TGF-β1 and CXCL9, with Smad2, Smad3, and Smad7 expression and cellular localization examined by Western blotting. We found that significantly more cells were undergoing EMT in fibrotic versus normal areas of lung in IPF surgical lung biopsy samples. CXCR3 was expressed by type II pneumocytes and fibroblasts in fibrotic areas in close proximity to cells undergoing EMT. In vitro, CXCL9 abrogated TGF-β1-induced EMT. A decrease in TGF-β1-induced phosphorylation of Smad2 and Smad3 occurred with CXCL9 treatment. This was associated with increased shuttling of Smad7 from the nucleus to the cytoplasm where it inhibits Smad phosphorylation. This suggests a role for EMT in the pathogenesis of IPF and provides a novel mechanism for the inhibitory effects of CXCL9 on TGF-β1-induced EMT. Copyright © 2015 by The American Association of Immunologists, Inc.

  20. Overcrowding drives the unjamming transition of gap-free monolayers

    Science.gov (United States)

    Lan, Ganhui; Su, Tao

    Collective cell motility plays central roles in various biological phenomena such as wound healing, cancer metastasis and embryogenesis. These are demonstrations of the unjamming transition in biology. However, contradictory to the typical density-driven jamming in particulate assemblies, cellular systems often get unjammed in highly packed, sometimes overcrowding environments. Here, we investigate monolayers' collective behaviors when cell number changes under the gap-free constraint. We report that overcrowding can unjam gap-free monolayers through increasing isotropic compression. We show that the transition boundary is determined by the isotropic compression and the cell-cell adhesion. Furthermore, we construct the free energy landscape for the T1 topological transition during monolayer rearrangement, and discover that the landscape evolves from single-barrier W shape to double-barrier M shape during the unjamming process. We also discover a distributed-to-disordered morphological transition of cells' geometry, coinciding with the unjamming transition. Our analyses reveal that the overcrowding and adhesion induced unjamming reflects the mechanical yielding of the highly deformable monolayer, suggesting an alternative mechanism that cells may robustly gain collective mobility through proliferation in confined environments, which differs from those caused by loosing up a packed particulate assembly. This work is supported by the GWU College Facilitating Funds.

  1. A novel derivative of doxorubicin, AD198, inhibits canine transitional cell carcinoma and osteosarcoma cells in vitro.

    Science.gov (United States)

    Rathore, Kusum; Cekanova, Maria

    2015-01-01

    Doxorubicin (DOX) is one of the most commonly used chemotherapeutic treatments for a wide range of cancers. N-benzyladriamycin-14-valerate (AD198) is a lipophilic anthracycline that has been shown to target conventional and novel isoforms of protein kinase C (PKC) in cytoplasm of cells. Because of the adverse effects of DOX, including hair loss, nausea, vomiting, liver dysfunction, and cardiotoxicity, novel derivatives of DOX have been synthesized and validated. In this study, we evaluated the effects of DOX and its derivative, AD198, on cell viability of three canine transitional cell carcinoma (K9TCC) (K9TCC#1-Lillie, K9TCC#2-Dakota, K9TCC#4-Molly) and three canine osteosarcoma (K9OSA) (K9OSA#1-Zoe, K9OSA#2-Nashville, K9OSA#3-JJ) primary cancer cell lines. DOX and AD198 significantly inhibited cell proliferation in all tested K9TCC and K9OSA cell lines in a dose-dependent manner. AD198 inhibited cell viability of tested K9TCC and K9OSA cell lines more efficiently as compared to DOX at the same concentration using MTS (3-(4,5-dimethyl-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2h-tetrazolium) assay. AD198 had lower IC50 values as compared to DOX for all tested K9TCC and K9OSA cell lines. In addition, AD198 increased apoptosis in all tested K9TCC and K9OSA cell lines. AD198 increased the caspase activity in tested K9TCC and K9OSA cell lines, which was confirmed by caspase-3/7 assay, and cleavage of poly (ADP-ribose) polymerase (PARP) was confirmed by Western blotting analysis. In addition, AD198 cleaved PKC-δ, which subsequently activated the p38 signaling pathway, resulting in the apoptosis of tested K9TCC and K9OSA cell lines. Inhibition of the p38 signaling pathway by SB203580 rescued DOX- and AD198-induced apoptosis in tested K9TCC and K9OSA cell lines. Our in vitro results suggest that AD198 might be considered as a new treatment option for K9TCC and K9OSA cell lines cancers in vivo.

  2. The mechanism of abrupt transition between theta and hyper-excitable spiking activity in medial entorhinal cortex layer II stellate cells.

    Directory of Open Access Journals (Sweden)

    Tilman Kispersky

    2010-11-01

    Full Text Available Recent studies have shown that stellate cells (SCs of the medial entorhinal cortex become hyper-excitable in animal models of temporal lobe epilepsy. These studies have also demonstrated the existence of recurrent connections among SCs, reduced levels of recurrent inhibition in epileptic networks as compared to control ones, and comparable levels of recurrent excitation among SCs in both network types. In this work, we investigate the biophysical and dynamic mechanism of generation of the fast time scale corresponding to hyper-excitable firing and the transition between theta and fast firing frequency activity in SCs. We show that recurrently connected minimal networks of SCs exhibit abrupt, threshold-like transition between theta and hyper-excitable firing frequencies as the result of small changes in the maximal synaptic (AMPAergic conductance. The threshold required for this transition is modulated by synaptic inhibition. Similar abrupt transition between firing frequency regimes can be observed in single, self-coupled SCs, which represent a network of recurrently coupled neurons synchronized in phase, but not in synaptically isolated SCs as the result of changes in the levels of the tonic drive. Using dynamical systems tools (phase-space analysis, we explain the dynamic mechanism underlying the genesis of the fast time scale and the abrupt transition between firing frequency regimes, their dependence on the intrinsic SC's currents and synaptic excitation. This abrupt transition is mechanistically different from others observed in similar networks with different cell types. Most notably, there is no bistability involved. 'In vitro' experiments using single SCs self-coupled with dynamic clamp show the abrupt transition between firing frequency regimes, and demonstrate that our theoretical predictions are not an artifact of the model. In addition, these experiments show that high-frequency firing is burst-like with a duration modulated by an M-current.

  3. CUX1/Wnt signaling regulates Epithelial Mesenchymal Transition in EBV infected epithelial cells

    International Nuclear Information System (INIS)

    Malizia, Andrea P.; Lacey, Noreen; Walls, Dermot; Egan, Jim J.; Doran, Peter P.

    2009-01-01

    Idiopathic pulmonary fibrosis (IPF) is a refractory and lethal interstitial lung disease characterized by alveolar epithelial cells apoptosis, fibroblast proliferation and extra-cellular matrix protein deposition. EBV, localised to alveolar epithelial cells of pulmonary fibrosis patients is associated with a poor prognosis. A strategy based on microarray-differential gene expression analysis to identify molecular drivers of EBV-associated lung fibrosis was utilized. Alveolar epithelial cells were infected with EBV to identify genes whose expression was altered following TGFβ1-mediated lytic phase. EBV lytic reactivation by TGFβ1 drives a selective alteration in CUX1 variant (a) (NCBI accession number NM 1 81552) expression, inducing activation of non-canonical Wnt pathway mediators, implicating it in Epithelial Mesenchymal Transition (EMT), the molecular event underpinning scar production in tissue fibrosis. The role of EBV in EMT can be attenuated by antiviral strategies and inhibition of Wnt signaling by using All-Trans Retinoic Acids (ATRA). Activation of non-canonical Wnt signaling pathway by EBV in epithelial cells suggests a novel mechanism of EMT via CUX1 signaling. These data present a framework for further description of the link between infectious agents and fibrosis, a significant disease burden.

  4. CUX1/Wnt signaling regulates Epithelial Mesenchymal Transition in EBV infected epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Malizia, Andrea P.; Lacey, Noreen [Clinical Research Centre, School of Medicine and Medical Science, University College Dublin. 21, Nelson Street. Dublin, 7. Ireland (Ireland); Walls, Dermot [School of Biotechnology, Dublin City University. Dublin, 9. Ireland (Ireland); Egan, Jim J. [Advanced Lung Disease and Lung Transplant Program, Mater Misericordiae University Hospital. 44, Eccles Street. Dublin, 7. Ireland (Ireland); Doran, Peter P., E-mail: peter.doran@ucd.ie [Clinical Research Centre, School of Medicine and Medical Science, University College Dublin. 21, Nelson Street. Dublin, 7. Ireland (Ireland)

    2009-07-01

    Idiopathic pulmonary fibrosis (IPF) is a refractory and lethal interstitial lung disease characterized by alveolar epithelial cells apoptosis, fibroblast proliferation and extra-cellular matrix protein deposition. EBV, localised to alveolar epithelial cells of pulmonary fibrosis patients is associated with a poor prognosis. A strategy based on microarray-differential gene expression analysis to identify molecular drivers of EBV-associated lung fibrosis was utilized. Alveolar epithelial cells were infected with EBV to identify genes whose expression was altered following TGF{beta}1-mediated lytic phase. EBV lytic reactivation by TGF{beta}1 drives a selective alteration in CUX1 variant (a) (NCBI accession number NM{sub 1}81552) expression, inducing activation of non-canonical Wnt pathway mediators, implicating it in Epithelial Mesenchymal Transition (EMT), the molecular event underpinning scar production in tissue fibrosis. The role of EBV in EMT can be attenuated by antiviral strategies and inhibition of Wnt signaling by using All-Trans Retinoic Acids (ATRA). Activation of non-canonical Wnt signaling pathway by EBV in epithelial cells suggests a novel mechanism of EMT via CUX1 signaling. These data present a framework for further description of the link between infectious agents and fibrosis, a significant disease burden.

  5. Circulating tumour cells escape from EpCAM-based detection due to epithelial-to-mesenchymal transition

    International Nuclear Information System (INIS)

    Gorges, Tobias M; Tinhofer, Ingeborg; Drosch, Michael; Röse, Lars; Zollner, Thomas M; Krahn, Thomas

    2012-01-01

    Circulating tumour cells (CTCs) have shown prognostic relevance in metastatic breast, prostate, colon and pancreatic cancer. For further development of CTCs as a biomarker, we compared the performance of different protocols for CTC detection in murine breast cancer xenograft models (MDA-MB-231, MDA-MB-468 and KPL-4). Blood samples were taken from tumour bearing animals (20 to 200 mm 2 ) and analysed for CTCs using 1. an epithelial marker based enrichment method (AdnaTest), 2. an antibody independent technique, targeting human gene transcripts (qualitative PCR), and 3. an antibody-independent approach, targeting human DNA-sequences (quantitative PCR). Further, gene expression changes associated with epithelial-to-mesenchymal transition (EMT) were determined with an EMT-specific PCR assay. We used the commercially available Adna Test, RT-PCR on human housekeeping genes and a PCR on AluJ sequences to detect CTCs in xenografts models. Phenotypic changes in CTCs were tested with the commercially available “Human Epithelial to Mesenchymal Transition RT-Profiler PCR Array”. Although the AdnaTest detects as few as 1 tumour cell in 1 ml of mouse blood spiking experiments, no CTCs were detectable with this approach in vivo despite visible metastasis formation. The presence of CTCs could, however, be demonstrated by PCR targeting human transcripts or DNA-sequences - without epithelial pre-enrichment. The failure of CTC detection by the AdnaTest resulted from downregulation of EpCAM, whereas mesenchymal markers like Twist and EGFR were upregulated on CTCs. Such a change in the expression profile during metastatic spread of tumour cells has already been reported and was linked to a biological program termed epithelial-mesenchymal transition (EMT). The use of EpCAM-based enrichment techniques leads to the failure to detect CTC populations that have undergone EMT. Our findings may explain clinical results where low CTC numbers have been reported even in patients with late

  6. Laparoscopic bilateral nephroureterectomy and bladder cuff excision for native renal pelvic and ureteral transitional cell carcinoma after renal transplantation.

    Directory of Open Access Journals (Sweden)

    Chen C

    2003-01-01

    Full Text Available A 37-years-old female who was suffering from end-stage renal disease for about 6 years received allograft renal transplantation 4 years ago. She has been receiving 50mg of Cyclosporin A orally daily for immuno-suppression since then. Gross haematuria was noted and computerised tomography showed native left renal pelvic and ureteral multi-focal transitional cell carcinoma with severe hydronephrosis. Laparoscopic bilateral nephroureterectomy and bladder cuff excision were performed. In the past, history of previous operation was considered a relative contraindication for laparoscopic surgery. To our knowledge, we present the first case of laparoscopic treatment for native renal pelvic and ureteral transitional cell carcinoma after renal allograft transplantation without a hand-assisted device. This case shows the feasibility of laparoscopic bilateral nephroureterectomy in patients with transplanted kidneys.

  7. GGPP-Mediated Protein Geranylgeranylation in Oocyte Is Essential for the Establishment of Oocyte-Granulosa Cell Communication and Primary-Secondary Follicle Transition in Mouse Ovary.

    Directory of Open Access Journals (Sweden)

    Chen Jiang

    2017-01-01

    Full Text Available Folliculogenesis is a progressive and highly regulated process, which is essential to provide ova for later reproductive life, requires the bidirectional communication between the oocyte and granulosa cells. This physical connection-mediated communication conveys not only the signals from the oocyte to granulosa cells that regulate their proliferation but also metabolites from the granulosa cells to the oocyte for biosynthesis. However, the underlying mechanism of establishing this communication is largely unknown. Here, we report that oocyte geranylgeranyl diphosphate (GGPP, a metabolic intermediate involved in protein geranylgeranylation, is required to establish the oocyte-granulosa cell communication. GGPP and geranylgeranyl diphosphate synthase (Ggpps levels in oocytes increased during early follicular development. The selective depletion of GGPP in mouse oocytes impaired the proliferation of granulosa cells, primary-secondary follicle transition and female fertility. Mechanistically, GGPP depletion inhibited Rho GTPase geranylgeranylation and its GTPase activity, which was responsible for the accumulation of cell junction proteins in the oocyte cytoplasm and the failure to maintain physical connection between oocyte and granulosa cells. GGPP ablation also blocked Rab27a geranylgeranylation, which might account for the impaired secretion of oocyte materials such as Gdf9. Moreover, GGPP administration restored the defects in oocyte-granulosa cell contact, granulosa cell proliferation and primary-secondary follicle transition in Ggpps depletion mice. Our study provides the evidence that GGPP-mediated protein geranylgeranylation contributes to the establishment of oocyte-granulosa cell communication and then regulates the primary-secondary follicle transition, a key phase of folliculogenesis essential for female reproductive function.

  8. Hedgehog Signaling Regulates Epithelial-Mesenchymal Transition in Pancreatic Cancer Stem-Like Cells

    Science.gov (United States)

    Wang, Feng; Ma, Ling; Zhang, Zhengkui; Liu, Xiaoran; Gao, Hongqiao; Zhuang, Yan; Yang, Pei; Kornmann, Marko; Tian, Xiaodong; Yang, Yinmo

    2016-01-01

    Hedgehog (Hh) signaling is crucially involved in tumorigenesis. This study aimed to assess the role of Hh signaling in the regulation of epithelial-mesenchymal transition (EMT), stemness properties and chemoresistance of human pancreatic Panc-1 cancer stem cells (CSCs). Panc-1 cells were transfected with recombinant lentiviral vectors to silence SMO and serum-free floating-culture system was used to isolate Panc-1 tumorspheres. The expression of CSC and EMT markers was detected by flow cytometry, real-time RT-PCR and Western blot analysis. Malignant behaviors of Panc-1 CSC were evaluated by tumorigenicity assays and nude mouse lung metastasis model. We found that tumorspheres derived from pancreatic cancer cell line Panc-1 possessed self-renewal, differentiation and stemness properties. Hh pathway and EMT were active in Panc-1 tumorspheres. Inhibition of Hh signaling by SMO knockdown inhibited self-renewal, EMT, invasion, chemoresistance, pulmonary metastasis, tumorigenesis of pancreatic CSCs. In conclusion, Hh signaling contributes to the maintenance of stem-like properties and chemoresistance of pancreatic CSC and promotes the tumorigenesis and metastasis of pancreatic cancer. Hh pathway is a potential molecular target for the development of therapeutic strategies for pancreatic CSCs. PMID:26918054

  9. Transitional cell carcinomas in four fishing cats (Prionailurus viverrinus).

    Science.gov (United States)

    Sutherland-Smith, Meg; Harvey, Catherine; Campbell, Mark; McAloose, Denise; Rideout, Bruce; Morris, Patrick

    2004-09-01

    Transitional cell carcinomas (TCC) of the urinary bladder were diagnosed in four related fishing cats (Prionailurus viverrinus). The major clinical sign in each case was persistent hematuria unresponsive to medical therapy. Cystotomy and biopsy provided an antemortem diagnosis in three of the fishing cats before euthanasia because of progression of clinical signs. The diagnosis was made in the fourth cat after euthanasia because of renal failure. Hematuria improved temporarily in one of the cats diagnosed antemortem and treated with piroxicam and carboplatin. Attempts to isolate a herpesvirus in two of the cats failed. Histopathologic appearance of the TCC was similar to that described for other species. TCC metastasis to the lungs was noted at necropsy in one cat; metastatic disease was not noted in the other fishing cats on gross or histopathologic examination. TCC of the urinary bladder appears to be more prevalent in fishing cats than in other species of domestic or nondomestic felids.

  10. Effect of proton and gamma irradiation on human lung carcinoma cells: Gene expression, cell cycle, cell death, epithelial–mesenchymal transition and cancer-stem cell trait as biological end points

    Energy Technology Data Exchange (ETDEWEB)

    Narang, Himanshi, E-mail: narangh@barc.gov.in [Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kumar, Amit [Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Bhat, Nagesh [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Pandey, Badri N.; Ghosh, Anu [Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2015-10-15

    Highlights: • Biological effectiveness of proton and gamma irradiation is compared in A549 cells. • Proton irradiation is two times more cytotoxic than gamma irradiation. • It alters ten times more number of early genes, as observed by microarray study. • It does not enhance cell migration, invasion and adhesion, unlike gamma irradiation. • It was more effective in reducing the percentage of cancer stem cell like cells. - Abstract: Proton beam therapy is a cutting edge modality over conventional gamma radiotherapy because of its physical dose deposition advantage. However, not much is known about its biological effects vis-a-vis gamma irradiation. Here we investigated the effect of proton- and gamma- irradiation on cell cycle, death, epithelial-mesenchymal transition (EMT) and “stemness” in human non-small cell lung carcinoma cells (A549). Proton beam (3 MeV) was two times more cytotoxic than gamma radiation and induced higher and longer cell cycle arrest. At equivalent doses, numbers of genes responsive to proton irradiation were ten times higher than those responsive to gamma irradiation. At equitoxic doses, the proton-irradiated cells had reduced cell adhesion and migration ability as compared to the gamma-irradiated cells. It was also more effective in reducing population of Cancer Stem Cell (CSC) like cells as revealed by aldehyde dehydrogenase activity and surface phenotyping by CD44{sup +}, a CSC marker. These results can have significant implications for proton therapy in the context of suppression of molecular and cellular processes that are fundamental to tumor expansion.

  11. Tracking costs of alternatively fueled buses in Florida.

    Science.gov (United States)

    2011-11-04

    The goal of the current project is to establish a recording and reporting mechanism for collecting field data on the performance and costs of alternatively fueled public transit vehicles operating in Florida in order to assist policy makers with thei...

  12. Ongoing evaluation of alternatively fueled buses : final report.

    Science.gov (United States)

    2016-05-01

    The goal of this project is to continue collecting and reporting data on the performance and costs of alternatively fueled public transit vehicles in Florida in a consistent manner. Over the course of this project, researchers sent repeated data requ...

  13. Surgical management of bladder transitional cell carcinoma in a vesicular diverticulum: case report.

    LENUS (Irish Health Repository)

    Raheem, Omer A

    2011-08-01

    We report a case of primary transitional cell carcinoma (TCC) of a bladder diverticum along with a literature review. A 55-year-old male presented with painless gross hematuria. A histological diagnosis of TCC within a bladder diverticulum was made following cystoscopical examination. Initially transurethral resection of bladder tumour with subsequent intravesical chemotherapy followed. As a result of recurrence and in view of bladder-sparing therapy, a distal partial cystectomy was performed. This report demonstrates that conservative bladder-sparing treatment can be achieved and subsequently followed by vigilant cystoscopy.

  14. Surgical management of bladder transitional cell carcinoma in a vesicular diverticulum: case report.

    LENUS (Irish Health Repository)

    Raheem, Omer A

    2012-02-01

    We report a case of primary transitional cell carcinoma (TCC) of a bladder diverticum along with a literature review. A 55-year-old male presented with painless gross hematuria. A histological diagnosis of TCC within a bladder diverticulum was made following cystoscopical examination. Initially transurethral resection of bladder tumour with subsequent intravesical chemotherapy followed. As a result of recurrence and in view of bladder-sparing therapy, a distal partial cystectomy was performed. This report demonstrates that conservative bladder-sparing treatment can be achieved and subsequently followed by vigilant cystoscopy.

  15. Frequent mutations of chromatin remodeling genes in transitional cell carcinoma of the bladder

    DEFF Research Database (Denmark)

    Gui, Yaoting; Guo, Guangwu; Huang, Yi

    2011-01-01

    frequently in tumors of low stages and grades, highlighting its potential role in the classification and diagnosis of bladder cancer. Our results provide an overview of the genetic basis of TCC and suggest that aberration of chromatin regulation might be a hallmark of bladder cancer.......Transitional cell carcinoma (TCC) is the most common type of bladder cancer. Here we sequenced the exomes of nine individuals with TCC and screened all the somatically mutated genes in a prevalence set of 88 additional individuals with TCC with different tumor stages and grades. In our study, we...

  16. Oxidative stress, mitochondrial permeability transition, and cell death in Cu-exposed trout hepatocytes

    International Nuclear Information System (INIS)

    Krumschnabel, Gerhard; Manzl, Claudia; Berger, Christian; Hofer, Bettina

    2005-01-01

    We have previously shown that, in trout hepatocytes, exposure to a high dose of copper (Cu) leads to disruption of Ca 2+ homeostasis and elevated formation of reactive oxygen species (ROS), with the latter ultimately causing cell death. In the present study, we aimed at identifying, using a lower Cu concentration, the role of mitochondria in this scenario, the potential involvement of the mitochondrial permeability transition (MPT), and the mode of cell death induced by the metal. Incubation with 10 μM Cu resulted in a strong stimulation of ROS formation, and after 2 h of exposure a significant increase of both apoptotic and necrotic cells was seen. Co-incubation of Cu-treated hepatocytes with the iron-chelator deferoxamine significantly inhibited ROS production and completely prevented cell death. The origin of the radicals generated was at least partly mitochondrial, as visualized by confocal laser scanning microscopy. Furthermore, ROS production was diminished by inhibition of mitochondrial respiration, but since this also aggravated the elevation of intracellular Ca 2+ induced by Cu, it did not preserve cell viability. In a sub-population of cells, Cu induced a decrease of mitochondrial membrane potential and occurrence of the MPT. Cyclosporin A, which did not inhibit ROS formation, prevented the onset of the MPT and inhibited apoptotic, but not necrotic, cell death. Cu-induced apoptosis therefore appears to be dependent on induction of the MPT, but the prominent contribution of mitochondria to ROS generation also suggests an important role of mitochondria in necrotic cell death

  17. Suppressor of fused (Sufu) promotes epithelial-mesenchymal transition (EMT) in cervical squamous cell carcinoma

    Science.gov (United States)

    Zhang, Ziyu; Zou, Yang; Liang, Meirong; Chen, Yuanting; Luo, Yong; Yang, Bicheng; Liu, Faying; Qin, Yunna; He, Deming; Wang, Feng; Huang, Ouping

    2017-01-01

    Suppressor of fused is essential for the maximal activation of Sonic Hedgehog signaling in development and tumorigenesis. However, the role of Sufu in cervical carcinoma remains unknown. Here, we report new findings of Sufu in regulating the epithelial-to-mesenchymal transition through the FoxM1 transcriptional modulation by 14-3-3ζ protein in cervical carcinoma. Sufu is overexpressed in cervical squamous cell carcinoma and its level in clinical tumor tissues is positively correlated with 14-3-3ζ. Functionanlly, siSufu remarkably prevents the cancer cell migration and invasion. We further demonstrate that the transcriptional activity of Sufu is increased by FoxM1, of which stability is promoted by 14-3-3ζ. Knockdown FoxM1 decreases the invasion of SiHa cells and reconstitution of Sufu rescues the invasion of these cells.Finally, overexpression of Sufu is significantly associated with differentiation grade, FIGO stage, Depth of stromal invasion and vascular cancer embolus. Our findings highlight a novel role for Sufu in cervical carcinogenesis. PMID:29371981

  18. Effects of transit bus interior configuration on performance of wheeled mobility users during simulated boarding and disembarking.

    Science.gov (United States)

    D'Souza, Clive; Paquet, Victor; Lenker, James A; Steinfeld, Edward

    2017-07-01

    The emergence of low-floor bus designs and related regulatory standards in the U.S. have resulted in substantial improvements in public transit accessibility. However, passengers using wheeled mobility devices still experience safety concerns and inefficiencies in boarding, disembarking, and interior circulation on low-floor buses. This study investigates effects of low-floor bus interior configuration and passenger crowding on boarding and disembarking efficiency and safety. Users of manual wheelchairs (n = 18), powered wheelchairs (n = 21) and electric scooters (n = 9) simulated boarding and disembarking in three interior layout configurations at low and high passenger crowding conditions on a full-scale laboratory mock-up of a low-floor bus. Dependent measures comprised task times and critical incidents during access ramp use, fare payment, and movement to and from the doorway and wheeled mobility securement area. Individual times for unassisted boarding ranged from 15.2 to 245.3 s and for disembarking ranged from 9.1 to 164.6 s across layout and passenger crowding conditions. Nonparametric analysis of variance showed significant differences and interactions across vehicle design conditions, passenger load and mobility device type on user performance. The configuration having electronic on-board fare payment, rear-bus entrance doorways and adjacent device securement areas demonstrated greatest efficiency and safety. High passenger load adversely impacted efficiency and frequency of critical incidents during on-board circulation across all three layouts. Findings have broader implications for improving transit system efficiency and quality of service across the spectrum of transit users. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Conditioned Medium from Adipose-Derived Stem Cells (ADSCs) Promotes Epithelial-to-Mesenchymal-Like Transition (EMT-Like) in Glioma Cells In vitro.

    Science.gov (United States)

    Iser, Isabele C; Ceschini, Stefanie M; Onzi, Giovana R; Bertoni, Ana Paula S; Lenz, Guido; Wink, Márcia R

    2016-12-01

    Mesenchymal stem cells (MSCs) have recently been described to home to brain tumors and to integrate into the tumor-associated stroma. Understanding the communication between cancer cells and MSCs has become fundamental to determine whether MSC-tumor interactions should be exploited as a vehicle for therapeutic agents or considered a target for intervention. Therefore, we investigated whether conditioned medium from adipose-derived stem cells (ADSCs-CM) modulate glioma tumor cells by analyzing several cell biology processes in vitro. C6 rat glioma cells were treated with ADSCs-CM, and cell proliferation, cell cycle, cell viability, cell morphology, adhesion, migration, and expression of epithelial-mesenchymal transition (EMT)-related surface markers were analyzed. ADSCs-CM did not alter cell viability, cell cycle, and growth rate of C6 glioma cells but increased their migratory capacity. Moreover, C6 cells treated with ADSC-CM showed reduced adhesion and underwent changes in cell morphology. Up-regulation of EMT-associated markers (vimentin, MMP2, and NRAS) was also observed following treatment with ADSC-CM. Our findings demonstrate that the paracrine factors released by ADSCs are able to modulate glioma cell biology. Therefore, ADSC-tumor cell interactions in a tumor microenvironment must be considered in the design of clinical application of stem cell therapy. Graphical Abstract Factors released by adipose-derived stem cells (ADSCs) may modulate the biology of C6 glioma cells. When C6 cells are exposed to a conditioned medium from adipose-derived stem cells (ADSCs-CM), some of these cells can undergo an EMT-like process and trans-differentiate into cells with a more mesenchymal phenotype, characterized by enhanced expression of EMT-related surface markers, reduced cell adhesion capacity, increased migratory capacity, as well as changes in cell and nuclei morphology.

  20. Mesenchymal Stromal Cell-Derived Interleukin-6 Promotes Epithelial-Mesenchymal Transition and Acquisition of Epithelial Stem-Like Cell Properties in Ameloblastoma Epithelial Cells.

    Science.gov (United States)

    Jiang, Chunmiao; Zhang, Qunzhou; Shanti, Rabie M; Shi, Shihong; Chang, Ting-Han; Carrasco, Lee; Alawi, Faizan; Le, Anh D

    2017-09-01

    Epithelial-mesenchymal transition (EMT), a biological process associated with cancer stem-like or cancer-initiating cell formation, contributes to the invasiveness, metastasis, drug resistance, and recurrence of the malignant tumors; it remains to be determined whether similar processes contribute to the pathogenesis and progression of ameloblastoma (AM), a benign but locally invasive odontogenic neoplasm. Here, we demonstrated that EMT- and stem cell-related genes were expressed in the epithelial islands of the most common histologic variant subtype, the follicular AM. Our results revealed elevated interleukin (IL)-6 signals that were differentially expressed in the stromal compartment of the follicular AM. To explore the stromal effect on tumor pathogenesis, we isolated and characterized both mesenchymal stromal cells (AM-MSCs) and epithelial cells (AM-EpiCs) from follicular AM and demonstrated that, in in vitro culture, AM-MSCs secreted a significantly higher level of IL-6 as compared to the counterpart AM-EpiCs. Furthermore, both in vitro and in vivo studies revealed that exogenous and AM-MSC-derived IL-6 induced the expression of EMT- and stem cell-related genes in AM-EpiCs, whereas such effects were significantly abrogated either by a specific inhibitor of STAT3 or ERK1/2, or by knockdown of Slug gene expression. These findings suggest that AM-MSC-derived IL-6 promotes tumor-stem like cell formation by inducing EMT process in AM-EpiCs through STAT3 and ERK1/2-mediated signaling pathways, implying a role in the etiology and progression of the benign but locally invasive neoplasm. Stem Cells 2017;35:2083-2094. © 2017 AlphaMed Press.

  1. A fuel cell city bus with three drivetrain configurations

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Junping [Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Xi' an Jiaotong University, Xi' an 710049 (China); Chen, Yong [School of Automobile and Transporting Engineering, Liaoning Institute of Technology, Jinzhou, Liaoning 121001 (China); Chen, Quanshi [State Key Laboratory of Automobile Safety and Energy Conservation, Tsinghua University, Beijing 100084 (China)

    2006-09-22

    Three fuel cell city buses of the energy hybrid- and power hybrid-type were re-engineered with three types of drivetrain configuration to optimize the structure and improve the performance. The energy distribution, hydrogen consumption, state of charge (SOC) and the power variation rate were analyzed when different drivetrain configurations and parameters were used. When powered only by a fuel cell, the bus cannot recover the energy through regenerative braking. The variation of the fuel cell power is large and frequent, which is not good for the fuel cell. When the fuel cell is linked to a battery pack in parallel, the bus can recover the energy through regenerative braking. The energy distribution is determined by the parameters of the fuel cell and the battery pack in the design stage to reduce the power variation rate of the fuel cell. When the fuel cell and DC/DC converter connected in series links the battery pack in parallel, energy can be recovered and the energy distribution can be adjusted online. The power variation rate of both the fuel cell and the battery pack are reduced. (author)

  2. A summary of design, policies and operational characteristics for shared bicycle/bus lanes.

    Science.gov (United States)

    2012-07-01

    This report contains the results of an investigation of the design and operation of shared bicycle/bus lanes in municipalities in the United States and other countries. These lanes are designated for use by public transit buses, bicycles, and usually...

  3. lncRNA H19 predicts poor prognosis in patients with melanoma and regulates cell growth, invasion, migration and epithelial–mesenchymal transition in melanoma cells

    Directory of Open Access Journals (Sweden)

    Shi G

    2018-06-01

    Full Text Available Gaofeng Shi,1,2 Hu Li,2 Fengshan Gao,2 Qian Tan1 1Drum Tower Clinical Medical College of Nanjing Medical University, Nanjing, People’s Republic of China; 2Department of Plastic Surgery, the Affiliated Wuxi No 4 People’s Hospital of Jiangnan University, Wuxi, People’s Republic of China Introduction: Melanoma is a deadly malignancy and the poor prognosis of patients with advanced disease is relatively poor. Recent studies indicate that long non-coding RNAs are involved in the pathogenesis of malignant melanoma. This study aims to investigate the role of the long non-coding RNA H19 in melanoma and to explore the underlying molecular mechanisms. Materials and methods: The expression levels of H19 in clinical samples and melanoma cells were determined by quantitative real-time PCR. The cell growth and cell metastasis were assessed by Cell Counting Kit 8, cell invasion and wound healing assays. Cell apoptosis and cell cycle were determined by flow cytometry. Protein levels were determined by Western blotting assay. Results: H19 was highly expressed in melanoma tissues compared to normal adjacent skin tissues, and the tissue expression level of H19 from melanoma patients with metastasis was significantly higher than that from patients without distant metastasis. In addition, the high expression of H19 in melanoma tissues was associated with advanced tumor invasion and TNM stage, distal metastasis, lymph node metastasis and shorter overall survival in patients with melanoma. The in vitro functional assays showed that knockdown of H19 inhibited cell growth, invasion and migration and also induced cell apoptosis as well as G0/G1 arrest in melanoma cells. Further quantitative real-time PCR and Western blot experiments showed that knockdown of H19 differentially regulated the epithelial–mesenchymal transition (EMT-related gene expressions and reversed EMT in melanoma cell lines. Knockdown of H19 suppressed in vivo tumor growth and modulated the

  4. Fisetin inhibits human melanoma cell invasion through promotion of mesenchymal to epithelial transition and by targeting MAPK and NFκB signaling pathways.

    Directory of Open Access Journals (Sweden)

    Harish Chandra Pal

    Full Text Available Malignant melanoma is responsible for approximately 75% of skin cancer-related deaths. BRAF plays an important role in regulating the mitogen-activated protein kinase (MAPK signaling cascade in melanoma with activating mutations in the serine/threonine kinase BRAF occurring in 60-70% of malignant melanomas. The BRAF-MEK-ERK (MAPK pathway is a key regulator of melanoma cell invasion. In addition, activation of NFκB via the MAPK pathway is regulated through MEK-induced activation of IKK. These pathways are potential targets for prevention and treatment of melanoma. In this study, we investigated the effect of fisetin, a phytochemical present in fruits and vegetables, on melanoma cell invasion and epithelial-mesenchymal transition, and delineated the underlying molecular mechanism. Treatment of multiple human malignant melanoma cell lines with fisetin (5-20 µM resulted in inhibition of cell invasion. BRAF mutated melanoma cells were more sensitive to fisetin treatment, and this was associated with a decrease in the phosphorylation of MEK1/2 and ERK1/2. In addition, fisetin inhibited the activation of IKK leading to a reduction in the activation of the NFκB signaling pathway. Treatment of cells with an inhibitor of MEK1/2 (PD98059 or of NFκB (caffeic acid phenethyl ester also reduced melanoma cell invasion. Furthermore, treatment of fisetin promoted mesenchymal to epithelial transition in melanoma cells, which was associated with a decrease in mesenchymal markers (N-cadherin, vimentin, snail and fibronectin and an increase in epithelial markers (E-cadherin and desmoglein. Employing three dimensional skin equivalents consisting of A375 cells admixed with normal human keratinocytes embedded onto a collagen-constricted fibroblast matrix, we found that treatment of fisetin reduced the invasive potential of melanoma cells into the dermis and increased the expression of E-cadherin with a concomitant decrease in vimentin. These results indicate that

  5. Fisetin Inhibits Human Melanoma Cell Invasion through Promotion of Mesenchymal to Epithelial Transition and by Targeting MAPK and NFκB Signaling Pathways

    Science.gov (United States)

    Pal, Harish Chandra; Sharma, Samriti; Strickland, Leah Ray; Katiyar, Santosh K.; Ballestas, Mary E.; Athar, Mohammad; Elmets, Craig A.; Afaq, Farrukh

    2014-01-01

    Malignant melanoma is responsible for approximately 75% of skin cancer-related deaths. BRAF plays an important role in regulating the mitogen-activated protein kinase (MAPK) signaling cascade in melanoma with activating mutations in the serine/threonine kinase BRAF occurring in 60–70% of malignant melanomas. The BRAF-MEK-ERK (MAPK) pathway is a key regulator of melanoma cell invasion. In addition, activation of NFκB via the MAPK pathway is regulated through MEK-induced activation of IKK. These pathways are potential targets for prevention and treatment of melanoma. In this study, we investigated the effect of fisetin, a phytochemical present in fruits and vegetables, on melanoma cell invasion and epithelial-mesenchymal transition, and delineated the underlying molecular mechanism. Treatment of multiple human malignant melanoma cell lines with fisetin (5–20 µM) resulted in inhibition of cell invasion. BRAF mutated melanoma cells were more sensitive to fisetin treatment, and this was associated with a decrease in the phosphorylation of MEK1/2 and ERK1/2. In addition, fisetin inhibited the activation of IKK leading to a reduction in the activation of the NFκB signaling pathway. Treatment of cells with an inhibitor of MEK1/2 (PD98059) or of NFκB (caffeic acid phenethyl ester) also reduced melanoma cell invasion. Furthermore, treatment of fisetin promoted mesenchymal to epithelial transition in melanoma cells, which was associated with a decrease in mesenchymal markers (N-cadherin, vimentin, snail and fibronectin) and an increase in epithelial markers (E-cadherin and desmoglein). Employing three dimensional skin equivalents consisting of A375 cells admixed with normal human keratinocytes embedded onto a collagen-constricted fibroblast matrix, we found that treatment of fisetin reduced the invasive potential of melanoma cells into the dermis and increased the expression of E-cadherin with a concomitant decrease in vimentin. These results indicate that fisetin

  6. Flocking transitions in confluent tissues.

    Science.gov (United States)

    Giavazzi, Fabio; Paoluzzi, Matteo; Macchi, Marta; Bi, Dapeng; Scita, Giorgio; Manning, M Lisa; Cerbino, Roberto; Marchetti, M Cristina

    2018-04-25

    Collective cell migration in dense tissues underlies important biological processes, such as embryonic development, wound healing and cancer invasion. While many aspects of single cell movements are now well established, the mechanisms leading to displacements of cohesive cell groups are still poorly understood. To elucidate the emergence of collective migration in mechanosensitive cells, we examine a self-propelled Voronoi (SPV) model of confluent tissues with an orientational feedback that aligns a cell's polarization with its local migration velocity. While shape and motility are known to regulate a density-independent liquid-solid transition in tissues, we find that aligning interactions facilitate collective motion and promote solidification, with transitions that can be predicted by extending statistical physics tools such as effective temperature to this far-from-equilibrium system. In addition to accounting for recent experimental observations obtained with epithelial monolayers, our model predicts structural and dynamical signatures of flocking, which may serve as gateway to a more quantitative characterization of collective motility.

  7. Research and development of a phosphoric acid fuel cell/battery power source integrated in a test-bed bus. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-30

    This project, the research and development of a phosphoric acid fuel cell/battery power source integrated into test-bed buses, began as a multi-phase U.S. Department of Energy (DOE) project in 1989. Phase I had a goal of developing two competing half-scale (25 kW) brassboard phosphoric acid fuel cell systems. An air-cooled and a liquid-cooled fuel cell system were developed and tested to verify the concept of using a fuel cell and a battery in a hybrid configuration wherein the fuel cell supplies the average power required for operating the vehicle and a battery supplies the `surge` or excess power required for acceleration and hill-climbing. Work done in Phase I determined that the liquid-cooled system offered higher efficiency.

  8. Kidins220/ARMS depletion is associated with the neural-to Schwann-like transition in a human neuroblastoma cell line model.

    Science.gov (United States)

    Rogers, Danny A; Schor, Nina F

    2013-03-10

    Peripheral neuroblastic tumors exist as a heterogeneous mixture of neuroblastic (N-type) cells and Schwannian stromal (S-type) cells. These stromal cells not only represent a differentiated and less aggressive fraction of the tumor, but also have properties that can influence the further differentiation of nearby malignant cells. In vitro neuroblastoma cultures exhibit similar heterogeneity with N-type and S-type cells representing the neuroblastic and stromal portions of the tumor, respectively, in behavior, morphology, and molecular expression patterns. In this study, we deplete kinase D-interacting substrate of 220kD (Kidins220) with an shRNA construct and thereby cause morphologic transition of the human SH-SY5Y neuroblastoma cell line from N-type to S-type. The resulting cells have similar morphology and expression profile to SH-EP1 cells, a native S-type cell line from the same parent cell line, and to SH-SY5Y cells treated with BrdU, a treatment that induces S-type morphology. Specifically, both Kidins220-deficient SH-SY5Y cells and native SH-EP1 cells demonstrate down-regulation of the genes DCX and STMN2, markers for the neuronal lineage. We further show that Kidins220, DCX and STMN2 are co-down-regulated in cells of S-type morphology generated by methods other than Kidins220 depletion. Finally, we report that the association of low Kidins220 expression with S-type morphology and low DCX and STMN2 expression is demonstrated in spontaneously occurring human peripheral neuroblastic tumors. We propose that Kidins220 is critical in N- to S-type transition of neural crest tumor cells. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Reprogramming of cell junction modules during stepwise epithelial to mesenchymal transition and accumulation of malignant features in vitro in a prostate cell model

    International Nuclear Information System (INIS)

    Ke, Xi-song; Li, Wen-cheng; Hovland, Randi; Qu, Yi; Liu, Run-hui; McCormack, Emmet; Thorsen, Frits; Olsen, Jan Roger; Molven, Anders; Kogan-Sakin, Ira; Rotter, Varda; Akslen, Lars A.; Oyan, Anne Margrete; Kalland, Karl-Henning

    2011-01-01

    Epithelial to mesenchymal transition (EMT) is pivotal in tumor metastasis. Our previous work reported an EMT model based on primary prostate epithelial cells (EP156T) which gave rise to cells with mesenchymal phenotype (EPT1) without malignant transformation. To promote prostate cell transformation, cells were maintained in saturation density cultures to select for cells overriding quiescence. Foci formed repeatedly following around 8 weeks in confluent EPT1 monolayers. Only later passage EPT1, but not EP156T cells of any passage, could form foci. Cells isolated from the foci were named EPT2 and formed robust colonies in soft agar, a malignant feature present neither in EP156T nor in EPT1 cells. EPT2 cells showed additional malignant traits in vitro, including higher ability to proliferate following confluence, higher resistance to apoptosis and lower dependence on exogenous growth factors than EP156T and EPT1 cells. Microarray profiling identified gene sets, many of which belong to cell junction modules, that changed expression from EP156T to EPT1 cells and continued to change from EPT1 to EPT2 cells. Our findings provide a novel stepwise cell culture model in which EMT emerges independently of transformation and is associated with subsequent accumulation of malignant features in prostate cells. Reprogramming of cell junction modules is involved in both steps.

  10. High Energy Batteries for Hybrid Buses

    Energy Technology Data Exchange (ETDEWEB)

    Bruce Lu

    2010-12-31

    EnerDel batteries have already been employed successfully for electric vehicle (EV) applications. Compared to EV applications, hybrid electric vehicle (HEV) bus applications may be less stressful, but are still quite demanding, especially compared to battery applications for consumer products. This program evaluated EnerDel cell and pack system technologies with three different chemistries using real world HEV-Bus drive cycles recorded in three markets covering cold, hot, and mild climates. Cells were designed, developed, and fabricated using each of the following three chemistries: (1) Lithium nickel manganese cobalt oxide (NMC) - hard carbon (HC); (2) Lithium manganese oxide (LMO) - HC; and (3) LMO - lithium titanium oxide (LTO) cells. For each cell chemistry, battery pack systems integrated with an EnerDel battery management system (BMS) were successfully constructed with the following features: real time current monitoring, cell and pack voltage monitoring, cell and pack temperature monitoring, pack state of charge (SOC) reporting, cell balancing, and over voltage protection. These features are all necessary functions for real-world HEV-Bus applications. Drive cycle test data was collected for each of the three cell chemistries using real world drive profiles under hot, mild, and cold climate conditions representing cities like Houston, Seattle, and Minneapolis, respectively. We successfully tested the battery packs using real-world HEV-Bus drive profiles under these various climate conditions. The NMC-HC and LMO-HC based packs successfully completed the drive cycles, while the LMO-LTO based pack did not finish the preliminary testing for the drive cycles. It was concluded that the LMO-HC chemistry is optimal for the hot or mild climates, while the NMC-HC chemistry is optimal for the cold climate. In summary, the objectives were successfully accomplished at the conclusion of the project. This program provided technical data to DOE and the public for assessing

  11. Human CD40 ligand-expressing type 3 innate lymphoid cells induce IL-10-producing immature transitional regulatory B cells.

    Science.gov (United States)

    Komlósi, Zsolt I; Kovács, Nóra; van de Veen, Willem; Kirsch, Anna Isabella; Fahrner, Heinz Benedikt; Wawrzyniak, Marcin; Rebane, Ana; Stanic, Barbara; Palomares, Oscar; Rückert, Beate; Menz, Günter; Akdis, Mübeccel; Losonczy, György; Akdis, Cezmi A

    2017-09-20

    Type 3 innate lymphoid cells (ILC3s) are involved in maintenance of mucosal homeostasis; however, their role in immunoregulation has been unknown. Immature transitional regulatory B (itBreg) cells are innate-like B cells with immunosuppressive properties, and the in vivo mechanisms by which they are induced have not been fully clarified. We aimed to investigate the ILC3-B-cell interaction that probably takes place in human tonsils. ILC3s were isolated from peripheral blood and palatine tonsils, expanded, and cocultured with naive B cells. Tonsillar ILC3s and regulatory B cells were visualized with immunofluorescence histology. ILC3 frequencies were measured in tonsil tissue of allergic and nonallergic patients and in peripheral blood of allergic asthmatic patients and healthy control subjects. A mutually beneficial relationship was revealed between ILC3s and B cells: ILC3s induced IL-15 production in B cells through B cell-activating factor receptor, whereas IL-15, a potent growth factor for ILC3s, induced CD40 ligand (CD40L) expression on circulating and tonsillar ILC3s. IL-15-activated CD40L + ILC3s helped B-cell survival, proliferation, and differentiation of IL-10-secreting, PD-L1-expressing functional itBreg cells in a CD40L- and B cell-activating factor receptor-dependent manner. ILC3s and regulatory B cells were in close connection with each other in palatine tonsils. ILC3 frequency was reduced in tonsil tissue of allergic patients and in peripheral blood of allergic asthmatic patients. Human CD40L + ILC3s provide innate B-cell help and are involved in an innate immunoregulatory mechanism through induction of itBreg cell differentiation, which takes place in palatine tonsils in vivo. This mechanism, which can contribute to maintenance of immune tolerance, becomes insufficient in allergic diseases. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  12. Walking school buses as a form of active transportation for children-a review of the evidence.

    Science.gov (United States)

    Smith, Liz; Norgate, Sarah H; Cherrett, Tom; Davies, Nigel; Winstanley, Christopher; Harding, Mike

    2015-03-01

    Walking school buses (WSBs) offer a potentially healthier way for children to get to school while reducing traffic congestion. A number of pressing societal challenges make it timely to evaluate evidence of their value. Studies that focused solely on WSBs were identified through online and manual literature searches. Twelve WSB studies involving a total of 9169 children were reviewed. Study aims, designs, methods, outcomes, and barriers and facilitators were examined. WSBs were found to be associated with increased prevalence of walking to school and general activity levels although not always significantly. Time constraints emerged as barriers to WSBs, impacting on recruitment of volunteers and children to the WSBs. Facilitators of WSBs included children enjoying socializing and interacting with the environment. Preliminary evidence of the health value of WSBs was demonstrated, along with recommendations for the design of future studies. By tackling barriers of time constraints, volunteer recruitment, and parents' safety concerns while at the same time, increasing convenience and time savings for families, future WSBs are likely to be more sustainable and taken up by more schools. Implications for future innovation in school health were identified. © 2015, American School Health Association.

  13. “Bus Lane Within The Area Of Intersection” Method For Buses Priority On The Intersections

    Directory of Open Access Journals (Sweden)

    Vikovych Ihor

    2015-12-01

    Full Text Available The primary objective of this article is to formalize the “special bus lanes within the area of intersection” method that allows providing buses with space-time priority at signalized intersections (mostly of the isolated type, including those with no more than two traffic lanes in each direction at the approaches to the intersection. The article establishes the limits for efficient application of this method, and describes the results of a simulation experiment conducted in the VISSIM environment to investigate the functioning of the method on an actual intersection. The most critical phase of implementation of this method is to determine the optimum length of the special bus lane at the approach to the intersection. The optimum length of special bus lanes at the approaches to isolated or coordinated intersections is determined based on the maximum length of queued vehicles which is computed using the simulation models developed in the Objective-C language. The article covers the basic characteristics of those models, their structure and building principles, and also provides the model validation results. Simulation models can be used both for determination of the optimum length of special bus lanes at the approaches to signalized intersections and for analysis of intersection performance based on the maximum length of queued vehicles.

  14. Sperm associated antigen 9 plays an important role in bladder transitional cell carcinoma.

    Directory of Open Access Journals (Sweden)

    Deepika Kanojia

    Full Text Available BACKGROUND: Majority of bladder cancer deaths are caused due to transitional cell carcinoma (TCC which is the most prevalent and chemoresistant malignancy of urinary bladder. Therefore, we analyzed the role of Sperm associated antigen 9 (SPAG9 in bladder TCC. METHODOLOGY AND FINDINGS: We examined SPAG9 expression and humoral response in 125 bladder TCC patients. Four bladder cancer cell lines were assessed for SPAG9 expression. In addition, we investigated the effect of SPAG9 ablation on cellular proliferation, cell cycle, migration and invasion in UM-UC-3 bladder cancer cells by employing gene silencing approach. Our SPAG9 gene and protein expression analysis revealed SPAG9 expression in 81% of bladder TCC tissue specimens. High SPAG9 expression (>60% SPAG9 positive cells was found to be significantly associated with superficial non-muscle invasive stage (P = 0.042 and low grade tumors (P = 0.002 suggesting SPAG9 putative role in early spread and tumorigenesis. Humoral response against SPAG9 was observed in 95% of patients found positive for SPAG9 expression. All four bladder cancer cell lines revealed SPAG9 expression. In addition, SPAG9 gene silencing in UM-UC-3 cells resulted in induction of G0-G1 arrest characterized by up-regulation of p16 and p21 and consequent down-regulation of cyclin E, cyclin D and cyclin B, CDK4 and CDK1. Further, SPAG9 gene silencing also resulted in reduction in cellular growth, and migration and invasion ability of cancer cells in vitro. CONCLUSIONS: Collectively, our data in clinical specimens indicated that SPAG9 is potential biomarker and therapeutic target for bladder TCC.

  15. In wound repair vimentin mediates the transition of mesenchymal leader cells to a myofibroblast phenotype.

    Science.gov (United States)

    Walker, J L; Bleaken, B M; Romisher, A R; Alnwibit, A A; Menko, A S

    2018-05-02

    Following injury, mesenchymal repair cells are activated to function as leader cells that modulate wound healing. These cells have the potential to differentiate to myofibroblasts, resulting in fibrosis and scarring. The signals underlying these differing pathways are complex and incompletely understood. The ex vivo mock cataract surgery cultures are an attractive model with which to address this question. With this model we study, concurrently, the mechanisms that control mesenchymal leader cell function in injury repair within their native microenvironment, and the signals that induce this same cell population to acquire a myofibroblast phenotype when these cells encounter the environment of the adjacent tissue culture platform. Here, we show that upon injury, the cytoskeletal protein vimentin is released into the extracellular space, binds to the cell surface of the mesenchymal leader cells located at the wound edge in the native matrix environment, and supports wound closure. In pro-fibrotic environments, the extracellular vimentin pool also links specifically to the mesenchymal leader cells, and has an essential role in signaling their fate change to a myofibroblast. These findings suggest a novel role for extracellular, cell-surface-associated vimentin in mediating repair-cell function in wound repair and in transitioning these cells to a myofibroblast phenotype. Movie S1 Movie S1 Collective movement of mesenchymal leader and epithelial follower cells across the tissue culture substrate (ECZ) in response to injury was followed by time-lapse imaging from D0-D3. The mesenchymal cells at the leading edge were easily distinguished morphologically from the lens epithelial follower cells.

  16. Transcriptional networks in epithelial-mesenchymal transition.

    Directory of Open Access Journals (Sweden)

    Christo Venkov

    Full Text Available Epithelial-mesenchymal transition (EMT changes polarized epithelial cells into migratory phenotypes associated with loss of cell-cell adhesion molecules and cytoskeletal rearrangements. This form of plasticity is seen in mesodermal development, fibroblast formation, and cancer metastasis.Here we identify prominent transcriptional networks active during three time points of this transitional process, as epithelial cells become fibroblasts. DNA microarray in cultured epithelia undergoing EMT, validated in vivo, were used to detect various patterns of gene expression. In particular, the promoter sequences of differentially expressed genes and their transcription factors were analyzed to identify potential binding sites and partners. The four most frequent cis-regulatory elements (CREs in up-regulated genes were SRY, FTS-1, Evi-1, and GC-Box, and RNA inhibition of the four transcription factors, Atf2, Klf10, Sox11, and SP1, most frequently binding these CREs, establish their importance in the initiation and propagation of EMT. Oligonucleotides that block the most frequent CREs restrain EMT at early and intermediate stages through apoptosis of the cells.Our results identify new transcriptional interactions with high frequency CREs that modulate the stability of cellular plasticity, and may serve as targets for modulating these transitional states in fibroblasts.

  17. Martin Luther King, Jr. East Busway in Pittsburgh, PA

    Science.gov (United States)

    1987-10-01

    The Port Authority of Allegheny County (PAT), the primary public transit operator in Pittsburgh, PA, built an exclusive roadway for buses which opened for service in February 1983. The two-lane, 6.8-mile facility serves the eastern suburbs via a righ...

  18. Salinomycin repressed the epithelial–mesenchymal transition of epithelial ovarian cancer cells via downregulating Wnt/β-catenin pathway

    Directory of Open Access Journals (Sweden)

    Li R

    2017-02-01

    Full Text Available Rui Li,* Taotao Dong,* Chen Hu, Jingjing Lu, Jun Dai, Peishu Liu Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University, Jinan, Shandong, People’s Republic of China *These authors contributed equally to this work Abstract: Epithelial ovarian cancer (EOC is the leading cause of death among all gynecological malignancies. Most patients are diagnosed in the advanced stage and have distant metastasis ultimately. Salinomycin has been demonstrated to reduce invasive capacity of multiple tumor cells. The objective of this study was to investigate the effects of salinomycin on EOC cells. The cell counting kit 8 (CCK-8 and Boyden chamber assays showed that salinomycin could effectively reduce the abilities of proliferation, migration and invasion in EOC cells. The western blot assay showed that salinomycin could increase the expression of epithelial markers (E-cadherin and Keratin while decrease the expression of mesenchymal markers (N-cadherin and vimentin in a dose-dependent manner. These results were ascertained by reverse transcription polymerase chain reaction (RT-PCR. Besides, salinomycin could downregulate the expression of proteins associated with the Wnt/β-catenin pathway and repress the nuclear translocation of β-catenin. It was also shown that salinomycin could reverse the aberrant activation of the canonical Wnt pathway induced by GSK-3β inhibitor (SB216763. Our results revealed that salinomycin could inhibit the proliferation, migration and invasion in EOC cells. In addition, the inhibitive effect of salinomycin on the invasive ability was mediated by repressing the epithelial–mesenchymal transition (EMT program, which may be achieved through its inhibition of the Wnt/β-catenin pathway. Keywords: salinomycin, epithelial–mesenchymal transition, epithelial ovarian cancer, Wnt/β-catenin pathway

  19. Solitary Laryngeal Metastasis from Transitional Cell Carcinoma of the Kidney: Clinical Case and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Tarek Assi

    2015-01-01

    Full Text Available The urogenital tract is a rare origin of laryngeal metastasis; transitional cell carcinoma with laryngeal metastases had never been reported previously. In this paper, we describe the clinical and pathological characteristics, evolution, and treatment of the first reported case of a laryngeal metastasis of a TCC followed by a brief review of the literature.

  20. Suitable parameter choice on quantitative morphology of A549 cell in epithelial–mesenchymal transition

    Science.gov (United States)

    Ren, Zhou-Xin; Yu, Hai-Bin; Li, Jian-Sheng; Shen, Jun-Ling; Du, Wen-Sen

    2015-01-01

    Evaluation of morphological changes in cells is an integral part of study on epithelial to mesenchymal transition (EMT), however, only a few papers reported the changes in quantitative parameters and no article compared different parameters for demanding better parameters. In the study, the purpose was to investigate suitable parameters for quantitative evaluation of EMT morphological changes. A549 human lung adenocarcinoma cell line was selected for the study. Some cells were stimulated by transforming growth factor-β1 (TGF-β1) for EMT, and other cells were as control without TGF-β1 stimulation. Subsequently, cells were placed in phase contrast microscope and three arbitrary fields were captured and saved with a personal computer. Using the tools of Photoshop software, some cells in an image were selected, segmented out and exchanged into unique hue, and other part in the image was shifted into another unique hue. The cells were calculated with 29 morphological parameters by Image Pro Plus software. A parameter between cells with or without TGF-β1 stimulation was compared statistically and nine parameters were significantly different between them. Receiver operating characteristic curve (ROC curve) of a parameter was described with SPSS software and F-test was used to compare two areas under the curves (AUCs) in Excel. Among them, roundness and radius ratio were the most AUCs and were significant higher than the other parameters. The results provided a new method with quantitative assessment of cell morphology during EMT, and found out two parameters, roundness and radius ratio, as suitable for quantification. PMID:26182364

  1. Interleukin‑6 induces an epithelial‑mesenchymal transition phenotype in human adamantinomatous craniopharyngioma cells and promotes tumor cell migration.

    Science.gov (United States)

    Zhou, Jie; Zhang, Chao; Pan, Jun; Chen, Ligang; Qi, Song-Tao

    2017-06-01

    Total resection of adamantinomatous craniopharyngioma (ACP) is complex and often leads to postoperative recurrence. This is due to the tendency of the tumor to invade the surrounding brain tissue and the generation of a local inflammatory state between the tumor cells and parenchyma. While there is evidence to suggest that interleukin‑6 (IL‑6) induces craniopharyngioma (CP)‑associated inflammation, particularly in ACP, the role of IL‑6 in the progression of ACP remains unclear. The results of the present study demonstrated that CP inflammation was associated with pathological classification, extent of surgery, degree of calcification and postoperative hypothalamic status scale. Cytokine antibody arrays were conducted to measure the expression of IL‑6 and other inflammatory factors in tumor tissues in response to various levels of inflammatory exposure. IL‑6, IL‑6 receptor (IL‑6R) and glycoprotein 130 expression was detected by immunohistochemistry. In addition, an ELISA was performed to quantify the levels of soluble IL‑6R (sIL‑6R) in the cystic fluid and supernatants of ACP cells and tumor‑associated fibroblasts. These measurements demonstrated that ACP cells produce IL‑6 and its associated proteins. In addition, the results revealed that while the viability of ACP cells was not affected, the migration of ACP cells was promoted by IL‑6 treatment in a concentration‑dependent manner. Conversely, treatment with an IL‑6‑blocking monoclonal antibody significantly decreased the migration of ACP cells. In addition, IL‑6 treatment increased the expression of vimentin and decreased the expression of E‑cadherin in a dose‑dependent manner. The findings of the present study demonstrate that IL‑6 may promote migration in vitro via the classic‑ and trans‑signaling pathways by inducing epithelial‑mesenchymal transition in ACP cell cultures.

  2. Interleukin-6 induces an epithelial-mesenchymal transition phenotype in human adamantinomatous craniopharyngioma cells and promotes tumor cell migration

    Science.gov (United States)

    Zhou, Jie; Zhang, Chao; Pan, Jun; Chen, Ligang; Qi, Song-Tao

    2017-01-01

    Total resection of adamantinomatous craniopharyngioma (ACP) is complex and often leads to postoperative recurrence. This is due to the tendency of the tumor to invade the surrounding brain tissue and the generation of a local inflammatory state between the tumor cells and parenchyma. While there is evidence to suggest that interleukin-6 (IL-6) induces craniopharyngioma (CP)-associated inflammation, particularly in ACP, the role of IL-6 in the progression of ACP remains unclear. The results of the present study demonstrated that CP inflammation was associated with pathological classification, extent of surgery, degree of calcification and postoperative hypothalamic status scale. Cytokine antibody arrays were conducted to measure the expression of IL-6 and other inflammatory factors in tumor tissues in response to various levels of inflammatory exposure. IL-6, IL-6 receptor (IL-6R) and glycoprotein 130 expression was detected by immunohistochemistry. In addition, an ELISA was performed to quantify the levels of soluble IL-6R (sIL-6R) in the cystic fluid and supernatants of ACP cells and tumor-associated fibroblasts. These measurements demonstrated that ACP cells produce IL-6 and its associated proteins. In addition, the results revealed that while the viability of ACP cells was not affected, the migration of ACP cells was promoted by IL-6 treatment in a concentration-dependent manner. Conversely, treatment with an IL-6-blocking monoclonal antibody significantly decreased the migration of ACP cells. In addition, IL-6 treatment increased the expression of vimentin and decreased the expression of E-cadherin in a dose-dependent manner. The findings of the present study demonstrate that IL-6 may promote migration in vitro via the classic- and trans-signaling pathways by inducing epithelial-mesenchymal transition in ACP cell cultures. PMID:28487953

  3. Circulating tumour cells escape from EpCAM-based detection due to epithelial-to-mesenchymal transition

    Directory of Open Access Journals (Sweden)

    Gorges Tobias M

    2012-05-01

    Full Text Available Abstract Background Circulating tumour cells (CTCs have shown prognostic relevance in metastatic breast, prostate, colon and pancreatic cancer. For further development of CTCs as a biomarker, we compared the performance of different protocols for CTC detection in murine breast cancer xenograft models (MDA-MB-231, MDA-MB-468 and KPL-4. Blood samples were taken from tumour bearing animals (20 to 200 mm2 and analysed for CTCs using 1. an epithelial marker based enrichment method (AdnaTest, 2. an antibody independent technique, targeting human gene transcripts (qualitative PCR, and 3. an antibody-independent approach, targeting human DNA-sequences (quantitative PCR. Further, gene expression changes associated with epithelial-to-mesenchymal transition (EMT were determined with an EMT-specific PCR assay. Methods We used the commercially available Adna Test, RT-PCR on human housekeeping genes and a PCR on AluJ sequences to detect CTCs in xenografts models. Phenotypic changes in CTCs were tested with the commercially available “Human Epithelial to Mesenchymal Transition RT-Profiler PCR Array”. Results Although the AdnaTest detects as few as 1 tumour cell in 1 ml of mouse blood spiking experiments, no CTCs were detectable with this approach in vivo despite visible metastasis formation. The presence of CTCs could, however, be demonstrated by PCR targeting human transcripts or DNA-sequences - without epithelial pre-enrichment. The failure of CTC detection by the AdnaTest resulted from downregulation of EpCAM, whereas mesenchymal markers like Twist and EGFR were upregulated on CTCs. Such a change in the expression profile during metastatic spread of tumour cells has already been reported and was linked to a biological program termed epithelial-mesenchymal transition (EMT. Conclusions The use of EpCAM-based enrichment techniques leads to the failure to detect CTC populations that have undergone EMT. Our findings may explain clinical results where low

  4. Activation of a cGMP-sensitive calcium-dependent chloride channel may cause transition from calcium waves to whole-cell oscillations in smooth muscle cells

    DEFF Research Database (Denmark)

    Jacobsen, Jens Christian; Aalkjær, Christian; Nilsson, Holger

    2007-01-01

    approximately doubles. In this transition, the simulated results point to a key role for a recently discovered cGMP-sensitive calcium-dependent chloride channel. This channel depolarizes the membrane in response to calcium released from the SR. In turn, depolarization causes uniform opening of L-type calcium...... channels on the cell surface stimulating synchronized release of SR-calcium and inducing the shift from waves to whole-cell oscillations. The effect of the channel is therefore to couple the processes of the SR with those of the membrane. We hypothesize that the shift in oscillatory mode and the associated...

  5. Stereotactic Body Radiotherapy for Localized Ureter Transitional Cell Carcinoma: Three Case Reports

    Directory of Open Access Journals (Sweden)

    Yoshiyasu Maehata

    2015-01-01

    Full Text Available The gold standard management for ureter transitional cell carcinoma (UTCC is radical nephroureterectomy with excision of the bladder cuff. However, some patients cannot undergo this procedure for several reasons. In the case reports described herein, we performed stereotactic body radiotherapy (SBRT on three patients with inoperable or surgery-rejected localized UTCC. Two out of the three patients did not develop local recurrence or distant metastasis during the observation period. However, recurrence was detected in the bladder of one patient 22 months after the treatment. No acute or late adverse events occurred in any of the three patients. SBRT may become one of the treatment options for inoperable or surgery-rejected UTCC patients.

  6. Evaluating the influential priority of the factors on insurance loss of public transit

    Science.gov (United States)

    Su, Yongmin; Chen, Xinqiang

    2018-01-01

    Understanding correlation between influential factors and insurance losses is beneficial for insurers to accurately price and modify the bonus-malus system. Although there have been a certain number of achievements in insurance losses and claims modeling, limited efforts focus on exploring the relative role of accidents characteristics in insurance losses. The primary objective of this study is to evaluate the influential priority of transit accidents attributes, such as the time, location and type of accidents. Based on the dataset from Washington State Transit Insurance Pool (WSTIP) in USA, we implement several key algorithms to achieve the objectives. First, K-means algorithm contributes to cluster the insurance loss data into 6 intervals; second, Grey Relational Analysis (GCA) model is applied to calculate grey relational grades of the influential factors in each interval; in addition, we implement Naive Bayes model to compute the posterior probability of factors values falling in each interval. The results show that the time, location and type of accidents significantly influence the insurance loss in the first five intervals, but their grey relational grades show no significantly difference. In the last interval which represents the highest insurance loss, the grey relational grade of the time is significant higher than that of the location and type of accidents. For each value of the time and location, the insurance loss most likely falls in the first and second intervals which refers to the lower loss. However, for accidents between buses and non-motorized road users, the probability of insurance loss falling in the interval 6 tends to be highest. PMID:29298337

  7. Experience of combined cisplatin and radiation therapy for advanced urinary tract transitional cell carcinoma

    International Nuclear Information System (INIS)

    Yoshioka, Toshiaki; Utsunomiya, Masato; Itoh, Hiroshi; Itatani, Hiroaki; Namiki, Mikio.

    1987-01-01

    Since March, 1981, 13 patients with locally advanced transitional cell carcinoma were treated by combined cisdiamminedichloroplatinum (cisplatin) and full dose radiotherapy. They were 10 men and 3 women. The patient ages ranged from 42 to 79 years, with a median of 59.5 years. The primary sites of transitional cell carcinoma were bladder in 5, ureter in 6, renal pelvis in 1 and prostate in 1. Radiotherapy consisted of a mean tumor dose of 48.7 gray, with a range of 40 to 66.4 gray, was administered with cobalt 60. Cisplatin was infused 5 days a week with a daily dose of 20 to 30 mg. 4 patients recieved 2 courses of cisplatin infusion and others 1 or less. Of the 4 evaluable patients 3 (75 %) achieved a complete response. Toxicity was evaluated for the 13 patients. Mainly gastrointestinal toxicity was noted: appetite loss in 9 (69.2 %), nausea and/or vomiting in 5 (38.5 %) and diarrhea in 5 (38.5 %). Leukocytopenia was noted in 7 patients (53.9 %), but in no one leukocyte count was less than 2000/mm 3 . Mild thrombocytopenia was noted only in 3 patients (23.1 %). All of these toxicities were mild, and the patients recovered soon after the therapy. Herein it is discussed about future problems such as solution of interaction mechanism, detection of practical dose and administering method of cisplatin and radiation. (author)

  8. Epithelial-Mesenchymal Transition in Kidney Tubular Epithelial Cells Induced by Globotriaosylsphingosine and Globotriaosylceramide.

    Directory of Open Access Journals (Sweden)

    Yeo Jin Jeon

    Full Text Available Fabry disease is a lysosomal storage disorder caused by deficiency of alpha-galactosidase A (α-gal A, which results in the deposition of globotriaosylceramide (Gb3 in the vascular endothelium. Globotriaosylsphingosine (lyso-Gb3, a deacylated Gb3, is also increased in the plasma of patients with Fabry disease. Renal fibrosis is a key feature of advanced Fabry disease patients. Therefore, we evaluated the association of Gb3 and lyso-Gb3 accumulation and the epithelial-mesenchymal transition (EMT on tubular epithelial cells of the kidney. In HK2 cells, exogenous treatments of Gb3 and lyso-Gb3 increased the expression of TGF-β, EMT markers (N-cadherin and α-SMA, and phosphorylation of PI3K/AKT, and decreased the expression of E-cadherin. Lyso-Gb3, rather than Gb3, strongly induced EMT in HK2 cells. In the mouse renal mesangial cell line, SV40 MES 13 cells, Gb3 strongly induced phenotype changes. The EMT induced by Gb3 was inhibited by enzyme α-gal A treatment, but EMT induced by lyso-Gb3 was not abrogated by enzyme treatment. However, TGF-β receptor inhibitor (TRI, SB525334 inhibited the activation of TGF-β and EMT markers in HK2 cells with Gb3 and lyso-Gb3 treatments. This study suggested that increased plasma lyso-Gb3 has a crucial role in the development of renal fibrosis through the cell-specific induction of the EMT in Fabry disease, and that TRI treatment, alongside enzyme replacement therapy, could be a potential therapeutic option for patients with Fabry disease.

  9. Snail1 induces epithelial-to-mesenchymal transition and tumor initiating stem cell characteristics

    International Nuclear Information System (INIS)

    Dang, Hien; Ding, Wei; Emerson, Dow; Rountree, C Bart

    2011-01-01

    Tumor initiating stem-like cells (TISCs) are a subset of neoplastic cells that possess distinct survival mechanisms and self-renewal characteristics crucial for tumor maintenance and propagation. The induction of epithelial-mesenchymal-transition (EMT) by TGFβ has been recently linked to the acquisition of TISC characteristics in breast cancer. In HCC, a TISC and EMT phenotype correlates with a worse prognosis. In this work, our aim is to elucidate the underlying mechanism by which cells acquire tumor initiating characteristics after EMT. Gene and protein expression assays and Nanog-promoter luciferase reporter were utilized in epithelial and mesenchymal phenotype liver cancer cell lines. EMT was analyzed with migration/invasion assays. TISC characteristics were analyzed with tumor-sphere self-renewal and chemotherapy resistance assays. In vivo tumor assay was performed to investigate the role of Snail1 in tumor initiation. TGFβ induced EMT in epithelial cells through the up-regulation of Snail1 in Smad-dependent signaling. Mesenchymal liver cancer post-EMT demonstrates TISC characteristics such as tumor-sphere formation but are not resistant to cytotoxic therapy. The inhibition of Snail1 in mesenchymal cells results in decreased Nanog promoter luciferase activity and loss of self-renewal characteristics in vitro. These changes confirm the direct role of Snail1 in some TISC traits. In vivo, the down-regulation of Snail1 reduced tumor growth but was not sufficient to eliminate tumor initiation. In summary, TGFβ induces EMT and TISC characteristics through Snail1 and Nanog up-regulation. In mesenchymal cells post-EMT, Snail1 directly regulates Nanog expression, and loss of Snail1 regulates tumor growth without affecting tumor initiation

  10. Down-regulation of Transducin-Like Enhancer of Split protein 4 in hepatocellular carcinoma promotes cell proliferation and epithelial-Mesenchymal-Transition

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Xiao-cai; Xiao, Cui-cui; Li, Hua [Department of Hepatic Surgery, 3rd Affiliated Hospital of Sun Yat-sen University, Guangzhou (China); Guangdong Provincial Key Laboratory of Liver Disease Research, Guangzhou (China); Tai, Yan; Zhang, Qi [Guangdong Provincial Key Laboratory of Liver Disease Research, Guangzhou (China); Yang, Yang, E-mail: yysysu2@163.com [Department of Hepatic Surgery, 3rd Affiliated Hospital of Sun Yat-sen University, Guangzhou (China)

    2016-08-19

    Background: Transducin-Like Enhancer of Split protein 4 (TLE4) has been reported to be involved in some subsets of acute myeloid leukemia and colorectal cancer. In the present study, we aimed to explore the role of TLE4 in tumorigenesis and cancer progression in hepatocellular carcinoma (HCC). Methods: The expression pattern of TLE4 in HCC was determined by Western-blot and qRT-PCR, gain-of-function and loss-of-function was used to explore the biological role of TLE4 in HCC cells. A xenograft model was established to confirm its effects on proliferation. Results: The protein expression levels of TLE4 were significantly down-regulated in HCC tissues compared to matched adjacent normal liver tissues. In vitro, down-regulation of TLE4 in Huh7 or SMMC-7721 promoted cell proliferation and ectopical expression of TLE4 in Hep3B or Bel-7404 suppressed cell proliferation. In addition, the cell colony formation ability was enhanced after down-regulation of TLE4 expression in Huh-7 but suppressed after over-expression in Hep3B. Furthermore, down-regulation of TLE4 increased the cell invasion ability, as well as increased the expression level of Vimentin and decreased that of E-cadherin, indicating a phenotype of epithelial-mesenchymal transition (EMT) in HCC cells. On the contrary, ectopical expression of TLE4 in HCC cells decreased the cell invasion ability and inhibited EMT. In vivo, compared to control group, xenograft tumor volumes were significantly decreased in TLE4 overexpression group. Conclusions: These results demonstrated that TLE4 might play important regulatory roles in cellular proliferation and EMT process in HCC. - Highlights: • TLE4 is significantly down-regulated in HCC samples. • Down regulated of TLE4 in HCC cells promotes cell proliferation. • Down regulated of TLE4 in HCC cells promotes epithelial-to-mesenchymal transition.

  11. CCAAT/enhancer binding protein beta (C/EBPβ) isoform balance as a regulator of epithelial-mesenchymal transition in mouse mammary epithelial cells

    International Nuclear Information System (INIS)

    Miura, Yuka; Hagiwara, Natsumi; Radisky, Derek C.; Hirai, Yohei

    2014-01-01

    Activation of the epithelial-mesenchymal transition (EMT) program promotes cell invasion and metastasis, and is reversed through mesenchymal-epithelial transition (MET) after formation of distant metastases. Here, we show that an imbalance of gene products encoded by the transcriptional factor C/EBPβ, LAP (liver-enriched activating protein) and LIP (liver-enriched inhibitory protein), can regulate both EMT- and MET-like phenotypic changes in mouse mammary epithelial cells. By using tetracycline repressive LIP expression constructs, we found that SCp2 cells, a clonal epithelial line of COMMA1-D cells, expressed EMT markers, lost the ability to undergo alveolar-like morphogenesis in 3D Matrigel, and acquired properties of benign adenoma cells. Conversely, we found that inducible expression of LAP in SCg6 cells, a clonal fibroblastic line of COMMA1-D cells, began to express epithelial keratins with suppression of proliferation. The overexpression of the C/EBPβ gene products in these COMMA1-D derivatives was suppressed by long-term cultivation on tissue culture plastic, but gene expression was maintained in cells grown on Matrigel or exposed to proteasome inhibitors. Thus, imbalances of C/EBPβ gene products in mouse mammary epithelial cells, which are affected by contact with basement membrane, are defined as a potential regulator of metastatic potential. - Highlights: • We created a temporal imbalance of C/EBPβ gene products in the mammary model cells. • The temporal up-regulation of LIP protein induced EMT-like cell behaviors. • The temporal up-regulation of LAP protein induced MET-like cell behaviors. • Excess amount of C/EBPβ gene products were eliminated by proteasomal-degradation. • Basement membrane components attenuated proteasome-triggered protein elimination

  12. Fuel economy and range estimates for fuel cell powered automobiles

    Energy Technology Data Exchange (ETDEWEB)

    Steinbugler, M.; Ogden, J. [Princeton Univ., NJ (United States)

    1996-12-31

    While a number of automotive fuel cell applications have been demonstrated, including a golf cart, buses, and a van, these systems and others that have been proposed have utilized differing configurations ranging from direct hydrogen fuel cell-only power plants to fuel cell/battery hybrids operating on reformed methanol. To date there is no clear consensus on which configuration, from among the possible combinations of fuel cell, peaking device, and fuel type, is the most likely to be successfully commercialized. System simplicity favors direct hydrogen fuel cell vehicles, but infrastructure is lacking. Infrastructure favors a system using a liquid fuel with a fuel processor, but system integration and performance issues remain. A number of studies have analyzed particular configurations on either a system or vehicle scale. The objective of this work is to estimate, within a consistent framework, fuel economies and ranges for a variety of configurations using flexible models with the goal of identifying the most promising configurations and the most important areas for further research and development.

  13. A novel derivative of doxorubicin, AD198, inhibits canine transitional cell carcinoma and osteosarcoma cells in vitro

    Directory of Open Access Journals (Sweden)

    Rathore K

    2015-09-01

    Full Text Available Kusum Rathore, Maria Cekanova Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN, USA Abstract: Doxorubicin (DOX is one of the most commonly used chemotherapeutic treatments for a wide range of cancers. N-benzyladriamycin-14-valerate (AD198 is a lipophilic anthracycline that has been shown to target conventional and novel isoforms of protein kinase C (PKC in cytoplasm of cells. Because of the adverse effects of DOX, including hair loss, nausea, vomiting, liver dysfunction, and cardiotoxicity, novel derivatives of DOX have been synthesized and validated. In this study, we evaluated the effects of DOX and its derivative, AD198, on cell viability of three canine transitional cell carcinoma (K9TCC (K9TCC#1-Lillie, K9TCC#2-Dakota, K9TCC#4-Molly and three canine osteosarcoma (K9OSA (K9OSA#1-Zoe, K9OSA#2-Nashville, K9OSA#3-JJ primary cancer cell lines. DOX and AD198 significantly inhibited cell proliferation in all tested K9TCC and K9OSA cell lines in a dose-dependent manner. AD198 inhibited cell viability of tested K9TCC and K9OSA cell lines more efficiently as compared to DOX at the same concentration using MTS (3-(4,5-dimethyl-2-yl-5-(3-carboxymethoxyphenyl-2-(4-sulfophenyl-2h-tetrazolium assay. AD198 had lower IC50 values as compared to DOX for all tested K9TCC and K9OSA cell lines. In addition, AD198 increased apoptosis in all tested K9TCC and K9OSA cell lines. AD198 increased the caspase activity in tested K9TCC and K9OSA cell lines, which was confirmed by caspase-3/7 assay, and cleavage of poly (ADP-ribose polymerase (PARP was confirmed by Western blotting analysis. In addition, AD198 cleaved PKC-δ, which subsequently activated the p38 signaling pathway, resulting in the apoptosis of tested K9TCC and K9OSA cell lines. Inhibition of the p38 signaling pathway by SB203580 rescued DOX- and AD198-induced apoptosis in tested K9TCC and K9OSA cell lines. Our in vitro results suggest

  14. 76 FR 46892 - Agency Information Collection Activity Under OMB Review

    Science.gov (United States)

    2011-08-03

    ... intention to request the Office of Management and Budget's (OMB) approval for the following new information... development and deployment of clean fuel and advanced propulsion technologies for transit buses. To meet program oversight responsibilities, FTA needs information on the operation and performance of clean fuel...

  15. Tracking costs of alternatively fueled buses in Florida : [summary].

    Science.gov (United States)

    2011-01-01

    In an effort to address rising fuel costs and environmental concerns, many transit agencies across Florida have introduced alternative fuel technologies to their traditional diesel-powered fleets. Fuel types include biodiesel, compressed natural gas,...

  16. MiR-200c suppresses the migration of retinoblastoma cells by reversing epithelial mesenchymal transition

    Directory of Open Access Journals (Sweden)

    Xiao-Lei Shao

    2017-08-01

    Full Text Available AIM: To analyze the relationship between clinical features and epithelial mesenchymal transition (EMT in retinoblastoma (RB, further to investigate whether miR-200c regulates the EMT and migration of RB cells. METHODS: Expression of EMT-related markers and tumor-related factors were detected by immuno-histochemistry analysis in RB tissue from 29 cases. Correlations between their expression and clinical characteristics were analyzed. The regulation effects of miR-200c on EMT-related markers, tumor-related factors were observed in mRNA level and protein level by real-time polymerase chain reaction (PCR and Western blot, respectively, in Y79 and Weri-rb1 cells. Its effects on migration force of these RB cell lines were also detected with Transwell test. RESULTS: Lower expression of E-cadherin was present in the cases with malignant prognosis. MiR-200c promoted the expression of E-cadherin and decreased the expression of Vimentin and N-cadherin in Y79 and Weri-rb1 cells. Migration force of RB cells could be inhibited by miR-200c. CONCLUSION: EMT might be associated with bad prognosis in RB. MiR-200c suppresses the migration of retinoblastomatous cells by reverse EMT.

  17. Lentiviral Vector Mediated Claudin1 Silencing Inhibits Epithelial to Mesenchymal Transition in Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Xianqi Zhao

    2015-06-01

    Full Text Available Breast cancer has a high incidence and mortality rate worldwide. Several viral vectors including lentiviral, adenoviral and adeno-associated viral vectors have been used in gene therapy for various forms of human cancer, and have shown promising effects in controlling tumor development. Claudin1 (CLDN1 is a member of the tetraspan transmembrane protein family that plays a major role in tight junctions and is associated with tumor metastasis. However, the role of CLDN1 in breast cancer is largely unexplored. In this study, we tested the therapeutic potential of silencing CLDN1 expression in two breast cancer (MDA-MB-231 and MCF7 cell lines using lentiviral vector mediated RNA interference. We found that a CLDN1 short hairpin (shRNA construct efficiently silenced CLDN1 expression in both breast cancer cell lines, and CLDN1 knockdown resulted in reduced cell proliferation, survival, migration and invasion. Furthermore, silencing CLDN1 inhibited epithelial to mesenchymal transition (EMT by upregulating the epithelial cell marker, E-cadherin, and downregulating mesenchymal markers, smooth muscle cell alpha-actin (SMA and Snai2. Our data demonstrated that lentiviral vector mediated CLDN1 RNA interference has great potential in breast cancer gene therapy by inhibiting EMT and controlling tumor cell growth.

  18. New portal axle for low-floor electric-powered city buses; Neue Portalachse fuer Niederflur-Stadtbusse mit E-Antrieb

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Axel Michael [ZF Friedrichshafen AG, Friedrichshafen (Germany); Solka, Ulrich [ZF Passau GmbH, Passau (Germany)

    2010-07-01

    Serial hybrid systems do have due to the very distinctive intra-urban driving cycles and the low average speeds in city bus applications very good technical characteristics regarding reduction of emissions and fuel consumption. Hence, in comparison to passenger car applications this technical solution has found a wide spreading in the field of city busses. This contribution describes the essential characteristics of the new-developed, electrically driven low floor portal axle AVE 130 for city buses from ZF. Beside the main features of the mechanical constructive assembly, the qualities of the electric drive with the features of the specifically developed asynchronous electrical machines are shown. Another main focus forms the description of the system characteristics of a city bus, which is equipped with a serial hybrid system and the new electrical portal axle. On this occasion, traction performances, aggregate arrangement, weight balances and the interaction of the components in the electrical driveline are discussed. Finally the results of simulation calculations regarding the fuel saving potential in such systems round the paper out. (orig.)

  19. Method for Backplane Data Communication with the VME Rear Transition Modules Developed for the ATLAS FTK Project

    CERN Document Server

    Bogdan, M; The ATLAS collaboration; Piendibene, M; Shochet, M; Tompkins, L

    2013-01-01

    This paper presents a method to achieve backplane data transfer capabilities to and from a VME Rear Transition Module (RTM), while being in full compliance with the VME64/VIPA Specification. The VMEbus is specified for data transfers only with boards plugged on the front side of the subrack. The RTMs receive power from the crate, but are not part of the actual data transfer bus. They do not plug into the J1 connector, and have no access to backplane interface logic. In this implementation, the RTM uses the feed-through pins located in the J2 connector to communicate with the corresponding front module. The front module's internal data, address, and control buses are extended to the rear. This allows the front module's interface block to control data transfers for logic devices on both sides of the same slot. All usual VME protocols to logic devices on the RTM become possible without any software adaptation. This method was implemented on several prototype modules developed for the ATLAS FTK Project. The full ...

  20. Plumbagin induces cell cycle arrest and autophagy and suppresses epithelial to mesenchymal transition involving PI3K/Akt/mTOR-mediated pathway in human pancreatic cancer cells

    Science.gov (United States)

    Wang, Feng; Wang, Qi; Zhou, Zhi-Wei; Yu, Song-Ning; Pan, Shu-Ting; He, Zhi-Xu; Zhang, Xueji; Wang, Dong; Yang, Yin-Xue; Yang, Tianxing; Sun, Tao; Li, Min; Qiu, Jia-Xuan; Zhou, Shu-Feng

    2015-01-01

    Plumbagin (PLB), an active naphthoquinone compound, has shown potent anticancer effects in preclinical studies; however, the effect and underlying mechanism of PLB for the treatment of pancreatic cancer is unclear. This study aimed to examine the pancreatic cancer cell killing effect of PLB and investigate the underlying mechanism in human pancreatic cancer PANC-1 and BxPC-3 cells. The results showed that PLB exhibited potent inducing effects on cell cycle arrest in PANC-1 and BxPC-3 cells via the modulation of cell cycle regulators including CDK1/CDC2, cyclin B1, cyclin D1, p21 Waf1/Cip1, p27 Kip1, and p53. PLB treatment concentration- and time-dependently increased the percentage of autophagic cells and significantly increased the expression level of phosphatase and tensin homolog, beclin 1, and the ratio of LC3-II over LC3-I in both PANC-1 and BxPC-3 cells. PLB induced inhibition of phosphatidylinositol 3-kinase (PI3K)/protein kinase B/mammalian target of rapamycin and p38 mitogen-activated protein kinase (p38 MAPK) pathways and activation of 5′-AMP-dependent kinase as indicated by their altered phosphorylation, contributing to the proautophagic activities of PLB in both cell lines. Furthermore, SB202190, a selective inhibitor of p38 MAPK, and wortmannin, a potent, irreversible, and selective PI3K inhibitor, remarkably enhanced PLB-induced autophagy in PANC-1 and BxPC-3 cells, indicating the roles of PI3K and p38 MAPK mediated signaling pathways in PLB-induced autophagic cell death in both cell lines. In addition, PLB significantly inhibited epithelial to mesenchymal transition phenotype in both cell lines with an increase in the expression level of E-cadherin and a decrease in N-cadherin. Moreover, PLB treatment significantly suppressed the expression of Sirt1 in both cell lines. These findings show that PLB promotes cell cycle arrest and autophagy but inhibits epithelial to mesenchymal transition phenotype in pancreatic cancer cells with the involvement of

  1. Design of a microbial fuel cell and its transition to microbial electrolytic cell for hydrogen production by electrohydrogenesis.

    Science.gov (United States)

    Gupta, Pratima; Parkhey, Piyush; Joshi, Komal; Mahilkar, Anjali

    2013-10-01

    Anaerobic bacteria were isolated from industrial wastewater and soil samples and tested for exoelectrogenic activity by current production in double chambered microbial fuel cell (MFC), which was further transitioned into a single chambered microbial electrolytic cell to test hydrogen production by electrohydrogenesis. Of all the cultures, the isolate from industrial water sample showed the maximum values for current = 0.161 mA, current density = 108.57 mA/m2 and power density = 48.85 mW/m2 with graphite electrode. Maximum voltage across the cell, however, was reported by the isolate from sewage water sample (506 mv) with copper as electrode. Tap water with KMnO4 was the best cathodic electrolyte as the highest values for all the measured MFC parameters were reported with it. Once the exoelectrogenic activity of the isolates was confirmed by current production, these were tested for hydrogen production in a single chambered microbial electrolytic cell (MEC) modified from the MFC. Hydrogen production was reported positive from co-culture of isolates of both the water samples and co-culture of one soil and one water sample. The maximum rate and yield of hydrogen production was 0.18 m3H2/m3/d and 3.2 mol H2/mol glucose respectively with total hydrogen production of 42.4 mL and energy recovery of 57.4%. Cumulative hydrogen production for a five day cycle of MEC operation was 0.16 m3H2/m3/d.

  2. Inhibiting glycogen synthase kinase-3 and transforming growth factor-β signaling to promote epithelial transition of human adipose mesenchymal stem cells.

    Science.gov (United States)

    Setiawan, Melina; Tan, Xiao-Wei; Goh, Tze-Wei; Hin-Fai Yam, Gary; Mehta, Jodhbir S

    2017-09-02

    This study was aimed to investigate the epithelial differentiation of human adipose-derived mesenchymal stem cells (ADSCs) by inhibiting glycogen synthase kinase-3 (GSK3) and transforming growth factor β (TGFβ) signaling. STEMPRO human ADSCs at passage 2 were treated with CHIR99021 (GSK3 inhibitor), E-616452 (TGFβ1 receptor kinase inhibitor), A-83-01 (TGFβ type 1 receptor inhibitor), valproic acid (histone deacetylase inhibitor), tranylcypromine (monoamine oxidase inhibitor) and all-trans retinoic acid for 72 h. The mesenchymal-epithelial transition was shown by down-regulation of mesenchymal genes (Slug, Zinc Finger E-box Binding Homeobox 1 ZEB1, integrin α5 ITGA5 and vimentin VIM) and up-regulation of epithelial genes (E-cadherin, Epithelial Cell Adhesion Molecule EpCAM, Zonula Occludens-1 ZO-1, occludin, deltaN p63 δNp63, Transcription Factor 4 TCF4 and Twist Family bHLH Transcription Factor TWIST), compared to untreated ADSCs. Cell morphology and stress fiber pattern were examined and the treated cells became less migratory in scratch wound closure assay. The formation of cell junction complexes was observed under transmission electron microscopy. Global gene expression using GeneChip ® Human Genome U133 Array (Affymetrix) showed that the treatment up-regulated 540 genes (containing genes for cell cycle, cytoskeleton reorganization, chemotaxis, epithelium development and regulation of cell migration) and down-regulated 483 genes. Human ADSCs were transited to epithelial lineage by inhibiting GSK3 and TGFβ signaling. It can be an adult stem cell source for epithelial cell-based therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. An in situ cell to study phase transitions in individual aerosol particles on a substrate using scanning transmission x-ray microspectroscopy

    International Nuclear Information System (INIS)

    Huthwelker, T.; Zelenay, V.; Birrer, M.; Krepelova, A.; Raabe, J.; Ammann, M.; Tzvetkov, G.; Vernooij, M. G. C.

    2010-01-01

    A new in situ cell to study phase transitions and chemical processes on individual aerosol particles in the x-ray transmission microscope at the PolLux beamline of the Swiss light source has been built. The cell is machined from stainless steel and aluminum components and is designed to be used in the standard mount of the microscope without need of complicated rearrangements of the microscope. The cell consists of two parts, a back part which contains connections for the gas supply, heating, cooling devices, and temperature measurement. The second part is a removable clip, which hosts the sample. This clip can be easily exchanged and brought into a sampling unit for aerosol particles. Currently, the cell can be operated at temperatures ranging from -40 to +50 deg. C. The function of the cell is demonstrated using two systems of submicron size: inorganic sodium bromide aerosols and soot originating from a diesel passenger car. For the sodium bromide we demonstrate how phase transitions can be studied in these systems and that O1s spectra from aqueous sodium bromide solution can be taken from submicron sized particles. For the case of soot, we demonstrate that the uptake of water onto individual soot particles can be studied.

  4. Radiological and cytological detection of renal pelvic transitional-cell carcinoma

    International Nuclear Information System (INIS)

    Paeivaensalo, M.; Merikanto, J.; Myllylae, V.; Hellstroem, P.; Kallionen, M.; Jalovaara, P.; Oulu Univ.; Oulu Univ.

    1990-01-01

    We evaluated US, CT, intraveneous urography, arteriography, retrograde pyelography and urine cytology results in a series of 23 patients with renal pelvic transitional-cell carcinomas, 14 of whom underwent US, 17 i.v. urography, 8 CT, 15 arteriography, 9 retrograde pyelography, and 17 patients urine cytology. A tumour was identified in 5 patients (36%) at US, in 11 patients (61%) at urography, in 7 (88%) at CT, in 10 patients (67%) at arteriography, and in 8 (89%) at retrograde pyelography. Urine cytology was assessed as showing changes consistent with Papanicolaou class III-V in 15 (88%) of 17 patients. When renal pelvic cancer is suspected, intravenous urography should be performed as the initial radiological examination and followed by CT, which may also identify tumour spread. Arteriography and retrograde pyelography are sometimes complementary investigations. Repeated urinary cytology is mandatory. Our results show that US alone is unreliable in detecting renal pelvic cancer. (orig.) [de

  5. Epithelial–mesenchymal transition during oncogenic transformation induced by hexavalent chromium involves reactive oxygen species-dependent mechanism in lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Song-Ze, E-mail: dingsongze@hotmail.com [Department of Internal Medicine, Henan Provincial People’s Hospital, Zhengzhou University, Wei-Wu Road, Zhengzhou, Henan 450000 (China); Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Yang, Yu-Xiu; Li, Xiu-Ling [Department of Internal Medicine, Henan Provincial People’s Hospital, Zhengzhou University, Wei-Wu Road, Zhengzhou, Henan 450000 (China); Michelli-Rivera, Audrey [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Han, Shuang-Yin [Department of Internal Medicine, Henan Provincial People’s Hospital, Zhengzhou University, Wei-Wu Road, Zhengzhou, Henan 450000 (China); Wang, Lei; Pratheeshkumar, Poyil; Wang, Xin; Lu, Jian; Yin, Yuan-Qin; Budhraja, Amit; Hitron, Andrew J. [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States)

    2013-05-15

    Hexavalent chromium [Cr(VI)] is an important human carcinogen associated with pulmonary diseases and lung cancer. Exposure to Cr(VI) induces DNA damage, cell morphological change and malignant transformation in human lung epithelial cells. Despite extensive studies, the molecular mechanisms remain elusive, it is also not known if Cr(VI)-induced transformation might accompany with invasive properties to facilitate metastasis. We aimed to study Cr(VI)-induced epithelial–mesenchymal transition (EMT) and invasion during oncogenic transformation in lung epithelial cells. The results showed that Cr(VI) at low doses represses E-cadherin mRNA and protein expression, enhances mesenchymal marker vimentin expression and transforms the epithelial cell into fibroblastoid morphology. Cr(VI) also increases cell invasion and promotes colony formation. Further studies indicated that Cr(VI) uses multiple mechanisms to repress E-cadherin expression, including activation of E-cadherin repressors such as Slug, ZEB1, KLF8 and enhancement the binding of HDAC1 in E-cadherin gene promoter, but DNA methylation is not responsible for the loss of E-cadherin. Catalase reduces Cr(VI)-induced E-cadherin and vimentin protein expression, attenuates cell invasion in matrigel and colony formation on soft agar. These results demonstrate that exposure to a common human carcinogen, Cr(VI), induces EMT and invasion during oncogenic transformation in lung epithelial cells and implicate in cancer metastasis and prevention. - Graphical abstract: Epithelial–mesenchymal transition during oncogenic transformation induced by hexavalent chromium involves reactive oxygen species-dependent mechanisms in lung epithelial cells. - Highlights: • We study if Cr(VI) might induce EMT and invasion in epithelial cells. • Cr(VI) induces EMT by altering E-cadherin and vimentin expression. • It also increases cell invasion and promotes oncogenic transformation. • Catalase reduces Cr(VI)-induced EMT, invasion and

  6. Upregulation of CD147 promotes cell invasion, epithelial-to-mesenchymal transition and activates MAPK/ERK signaling pathway in colorectal cancer

    OpenAIRE

    Xu, Tao; Zhou, Mingliang; Peng, Lipan; Kong, Shuai; Miao, Ruizheng; Shi, Yulong; Sheng, Hongguang; Li, Leping

    2014-01-01

    Colorectal cancer (CRC) is one of the most common cancers in the world. CD147, a transmembrane protein, has been reported to be correlated with various cancers. In this study, we aimed to investigate the mechanism of CD147 in regulating drug resistance, cell invasion and epithelial-to-mesenchymal transition (EMT) in CRC cells. qRT-PCR and western blotting were used to evaluated the expression of CD147 in 40 CRC cases and 4 cell lines. Increased expression of CD147 at both mRNA and protein lev...

  7. In vitro investigation of a tissue-engineered cell-tendon complex mimicking the transitional architecture at the ligament-bone interface.

    Science.gov (United States)

    Wang, Zhibing; Zhang, Yuan; Zhu, Jie; Dong, Shiwu; Jiang, Tao; Zhou, Yue; Zhang, Xia

    2015-03-01

    Restoration of the transitional ligament-bone interface is critical for graft-bone integration. We postulated that an allogenic scaffold mimicking the fibrogenic, chondrogenic, and osteogenic transition gradients could physiologically promote ligament-bone incorporation. The aim of this study was to construct and characterize a composite tendon scaffold with a continuous and heterogeneous transition region mimicking a native ligament insertion site. Genetically modified heterogeneous cell populations were seeded within specific regions of decellularized rabbit Achilles tendons to fabricate a stratified scaffold containing three biofunctional regions supporting fibrogenesis, chondrogenesis, and osteogenesis. The observed morphology, architecture, cytocompatibility, and biomechanics of the scaffolds demonstrated their improved bio-physico-chemical properties. The formation of the transitional regions was augmented via enhanced delivery of two transcription factors, sex determining region Y-box 9 and runt-related transcription factor 2, which also triggered early up-regulated expression of cartilage- and bone-relevant markers, according to quantitative PCR and immunoblot analyses. Gradient tissue-specific matrix formation was also confirmed within the predesignated regions via histological staining and immunofluorescence assays. These results suggest that a transitional interface could be replicated on an engineered tendon through stratified tissue integration. The scaffold offers the advantages of a multitissue transition involving controlled cellular interactions and matrix heterogeneity, which can be applied for the regeneration of the ligament-bone interface. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  8. Epithelial-mesenchymal transition is associated with increased ...

    African Journals Online (AJOL)

    Yomi

    2011-12-16

    Dec 16, 2011 ... Key words: SMMC-7721, cancer stem cells, side population cells, invasion, epithelial-mesenchymal transition. INTRODUCTION. Invasion and metastasis are the most important biological ..... the metastatic phenotype of pancreatic cancer cells with- ... occludens-1 (ZO-1), and gain mesenchymal molecular.

  9. Heterostructures of phosphorene and transition metal dichalcogenides for excitonic solar cells: A first-principles study

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Vellayappan Dheivanayagam; Shen, Lei, E-mail: shenlei@nus.edu.sg [Engineering Science Programme, National University of Singapore, 9 Engineering Drive 1, Singapore 117575 (Singapore); Linghu, Jiajun; Zhang, Chun; Feng, Yuan Ping [Department of Physics, National University of Singapore, Singapore 117542 (Singapore)

    2016-03-21

    Using the many-body perturbation GW theory, we study the quasiparticle conduction-band offsets of phosphorene, a two-dimensional atomic layer of black phosphorus, and transition-metal dichalcogenides (TMDs). The calculated large exciton binding energies of phosphorene and TMDs indicate that their type-II heterostructures are suitable for excitonic thin-film solar cell applications. Our results show that these heterojunctions have a potential maximum power conversion efficiency of up to 12%, which can be further enhanced up to 20% by strain engineering.

  10. Heterostructures of phosphorene and transition metal dichalcogenides for excitonic solar cells: A first-principles study

    International Nuclear Information System (INIS)

    Ganesan, Vellayappan Dheivanayagam; Shen, Lei; Linghu, Jiajun; Zhang, Chun; Feng, Yuan Ping

    2016-01-01

    Using the many-body perturbation GW theory, we study the quasiparticle conduction-band offsets of phosphorene, a two-dimensional atomic layer of black phosphorus, and transition-metal dichalcogenides (TMDs). The calculated large exciton binding energies of phosphorene and TMDs indicate that their type-II heterostructures are suitable for excitonic thin-film solar cell applications. Our results show that these heterojunctions have a potential maximum power conversion efficiency of up to 12%, which can be further enhanced up to 20% by strain engineering.

  11. Metformin inhibits 17?-estradiol-induced epithelial-to-mesenchymal transition via ?Klotho-related ERK1/2 signaling and AMPK? signaling in endometrial adenocarcinoma cells

    OpenAIRE

    Liu, Zhao; Qi, Shasha; Zhao, Xingbo; Li, Mingjiang; Ding, Sentai; Lu, Jiaju; Zhang, Hui

    2016-01-01

    The potential role of metformin in treating endometrial cancer remains to be explored. The current study investigated the role of metformin in 17?-estradiol-induced epithelial-mesenchymal transition (EMT) in endometrial adenocarcinoma cells. We found that 17?-estradiol promoted proliferation and migration, attenuated apoptosis in both estrogen receptor (ER) positive and ER negative endometrial adenocarcinoma cells (Ishikawa and KLE cells, respectively). Metformin abolished 17?-estradiol-induc...

  12. Technological capability assessment of suppliers to support product development: case study on a buses and coaches manufacturer

    Directory of Open Access Journals (Sweden)

    Lucas Comerlato

    2013-05-01

    Full Text Available Supply chain management has become a critical issue in the global collaboration scenario. Suppliers are not expected to provide just commodities or pre-defined components, but also collaborative engineering design solutions within the product development cycle. Thus, the selection criteria for defining supply partner go beyond the production and logistic capabilities, but must also include technical and engineering competence. This, in some sense, can be considered a common scenario of big companies, but is still challenging when dealing with SME´s. This work discusses how SME´s can be included in a supply chains taking in consideration a set of parameters to assess their technical competence related to product development collaboration. A set of eight parameters has been proposed to assess the engineering team competence, physical and technological structure and further legal responsibility. For each parameter values and weights were defined also. The assessment was applied to three companies that are suppliers of a buses and coaches manufacturer from Rio Grande do Sul, Brazil. The results show that even when dealing with objective parameters, the suppliers and costumer can have different perceptions about same issues.

  13. 25 CFR 170.152 - What transit facilities and activities are eligible for IRR Program funding?

    Science.gov (United States)

    2010-04-01

    ... development, such as bus shelters in shopping centers, parking lots, pedestrian improvements, and support facilities that incorporate other community services; (h) Passenger shelters, bus stop signs, and similar..., buildings, facilities, buses, vans, water craft, and other vehicles for use in mass transportation; (b...

  14. 77 FR 60170 - Americans With Disabilities Act: Proposed Circular Chapter, Vehicle Acquisition

    Science.gov (United States)

    2012-10-02

    ... specifications in Part 38 by vehicle type. The section begins by emphasizing that an accessible bus or rail car... With Disabilities Act: Proposed Circular Chapter, Vehicle Acquisition AGENCY: Federal Transit... buses and rail cars they acquire meet the requirements of the U.S. Department of Transportation's (DOT...

  15. MicroRNA-29b regulates TGF-β1-mediated epithelial–mesenchymal transition of retinal pigment epithelial cells by targeting AKT2

    Energy Technology Data Exchange (ETDEWEB)

    Li, Min; Li, Hui; Liu, Xiaoqiang; Xu, Ding; Wang, Fang, E-mail: milwang_122@msn.com

    2016-07-15

    The role of microRNA (miRNA) in proliferative vitreoretinopathy (PVR) progression has not been studied extensively, especially in retinal pigment epithelial–mesenchymal transition (EMT) which is the main reason for formation of PVR. In this study, we first investigated the miRNA expression profile in transforming growth factor beta 1 (TGF-β1) mediated EMT of ARPE-19 cells. Among the five changed miRNAs, miR-29b showed the most significant downregulation. Enhanced expression of miR-29b could reverse TGF-β1 induced EMT through targeting Akt2. Akt2 downregulation could inhibit TGF-β1-induced EMT. Furthermore, inhibition of miR-29b in ARPE-19 cells directly triggered EMT process, which characterized by the phenotypic transition and the upregulation of α-smooth muscle actin (α-SMA) and downregulation of E-cadherin and zona occludin-1 (ZO-1) with increased cell migration. Akt2-shRNA also inhibited miR-29 inhibitor-induced EMT process. These data indicate that miR-29b plays an important role in TGF-β1-mediated EMT in ARPE-19 cells by targeting Akt2. - Highlights: • MiR-29b expression is decreased in TGF-β1-induced EMT of ARPE-19 cells. • MiR-29b inhibits TGF-β1-induced EMT in ARPE-19 cells. • MiR-29b inhibitor induces EMT in ARPE-19 cells. • Akt2 is the target for miR-29b. • Downregulation of Akt2 prevents TGF-β1-induced EMT of ARPE-19 cells.

  16. Complete en bloc urinary exenteration for synchronous multicentric transitional cell carcinoma with sarcomatoid features in a hemodialysis patient

    Directory of Open Access Journals (Sweden)

    Tiberio M. Siqueira Jr

    2006-10-01

    Full Text Available The incidence of transitional cell carcinoma (TCC in patients submitted to hemodialysis is low. The presence of TCC with sarcomatoid features in this cohort is even scarcer. Herein, we describe a very rare case of synchronous multicentric muscle invasive bladder carcinoma with prostate invasion in a hemodialysis patient, submitted to complete en bloc urinary exenteration.

  17. Transcriptional Reprogramming during Effector-to-Memory Transition Renders CD4+ T Cells Permissive for Latent HIV-1 Infection.

    Science.gov (United States)

    Shan, Liang; Deng, Kai; Gao, Hongbo; Xing, Sifei; Capoferri, Adam A; Durand, Christine M; Rabi, S Alireza; Laird, Gregory M; Kim, Michelle; Hosmane, Nina N; Yang, Hung-Chih; Zhang, Hao; Margolick, Joseph B; Li, Linghua; Cai, Weiping; Ke, Ruian; Flavell, Richard A; Siliciano, Janet D; Siliciano, Robert F

    2017-10-17

    The latent reservoir for HIV-1 in resting memory CD4 + T cells is the major barrier to curing HIV-1 infection. Studies of HIV-1 latency have focused on regulation of viral gene expression in cells in which latent infection is established. However, it remains unclear how infection initially becomes latent. Here we described a unique set of properties of CD4 + T cells undergoing effector-to-memory transition including temporary upregulation of CCR5 expression and rapid downregulation of cellular gene transcription. These cells allowed completion of steps in the HIV-1 life cycle through integration but suppressed HIV-1 gene transcription, thus allowing the establishment of latency. CD4 + T cells in this stage were substantially more permissive for HIV-1 latent infection than other CD4 + T cells. Establishment of latent HIV-1 infection in CD4 + T could be inhibited by viral-specific CD8 + T cells, a result with implications for elimination of latent HIV-1 infection by T cell-based vaccines. Copyright © 2017. Published by Elsevier Inc.

  18. Epithelial–mesenchymal-transition induced by EGFR activation interferes with cell migration and response to irradiation and cetuximab in head and neck cancer cells

    International Nuclear Information System (INIS)

    Holz, Carmen; Niehr, Franziska; Boyko, Mariya; Hristozova, Tsvetana; Distel, Luitpold; Budach, Volker; Tinhofer, Ingeborg

    2011-01-01

    Background and purpose: The role of epithelial–mesenchymal transition (EMT) in the poor outcome of EGFR-overexpressing SCCHN was evaluated. Material and methods: SCCHN cell lines were characterized for their cell morphology and expression of EGFR and the EMT-associated factors E-cadherin, vimentin and Snail1. The migratory potential of cells was assessed in motility assays. Response to irradiation and cetuximab was determined using clonogenic survival assays. Results: High basal expression of E-cadherin but low to absent vimentin expression could be observed in all SCCHN cell lines. Although E-cadherin expression levels did not change after treatment with EGF we observed a significant change in cell morphology resembling EMT. SCCHN cells with high basal levels of Snail1 resulting from constitutive EGFR activation were characterized by mesenchymal-like morphology, elevated migratory potential, reduced sensitivity to irradiation and cetuximab but increased sensitivity to the combined treatment. Conclusions: Autocrine activation of EGFR leading to EMT is associated with a metastatic phenotype and reduced sensitivity of SCCHN cells to single-modality treatment with cetuximab or irradiation. The potential of Snail1 as biomarker for selection of patients who will mostly benefit from a combination of cetuximab and radiotherapy has to be evaluated in future clinical studies.

  19. Alternative fuel news: Official publication of the clean cities network and the alternative fuels data center, Vol. 4, No. 1

    Energy Technology Data Exchange (ETDEWEB)

    NREL

    2000-03-27

    This issue of Alternative Fuel News contains information on the upcoming Clean Cities Conference to be held May 7--10, 2000 in San Diego, California. Highlighted in this issue is the success of the Clean Cities Program in creating clean corridors that permit fleets that serve multiple cities to purchase AFVs with confidence, knowing that fueling convenience and supply will not be a problem. Also look for articles on electric vehicles, transit buses; state and fuel provider enforcement; the Salt Lake and Greater Long Island Clean Cities coalitions, HEVs and fuel cells are a big hit at auto shows; DOE awards alternative fuel grants to 33 National Parks; and the Energy Policy Act (EPAct) Section 506 report.

  20. Analyzing the Relationship Between Bus Pollution Policies and Morbidity Using a Quasi-Experiment.

    Science.gov (United States)

    Ngo, Nicole S

    2015-09-01

    Transit buses are used by millions of commuters every day, but they emit toxic diesel fumes. In 1988, the U.S. Environmental Protection Agency implemented emission standards for transit buses, which have been continually updated. Yet there is no quantitative evidence of the health benefits from these bus pollution policies due to data constraints and confounding variables. In this study, a quasi-experiment is used to exploit the geographic and temporal variation in emission standards by using bus vintage as a proxy for bus emissions. This is accomplished using a unique, rich panel data set, which includes daily information on bus vintage and route for the New York City Transit bus fleet between 2006 and 2009. This information is merged with daily data on emergency department (ED) visits for respiratory illnesses, which include patients' residences at the census block level and exact admission date. Economic benefits resulting from these bus pollution policies are then estimated. Results show that stricter transit bus emission standards by the U.S. Environmental Protection Agency for particulate matter are associated with reduced ED visits for respiratory diseases for patients living within a few hundred feet of a bus route. These findings demonstrate that bus pollution policies have made critical improvements to public health.

  1. Adipocytes Promote B16BL6 Melanoma Cell Invasion and the Epithelial-to-Mesenchymal Transition

    OpenAIRE

    Kushiro, Kyoko; Chu, Randy A.; Verma, Akanksha; Núñez, Nomelí P.

    2011-01-01

    Metastatic melanoma is one of the most deadly and evasive types of cancer. On average, cancer patients with metastatic melanoma survive only 6–9 months after diagnosis. Epidemiological and animal studies suggest that obesity increases the metastatic ability of malignant melanoma, though the mechanism is not known. In the present studies, we assessed the ability of 3T3L1 adipocytes to modulate B16BL6 melanoma cell invasion and the Epithelial-to-Mesenchymal Transition (EMT). For this purpose, w...

  2. How do generalized jamming transitions affect collective migration in confluent tissues?

    Science.gov (United States)

    Manning, M. Lisa

    Recent experiments have demonstrated that tissues involved in embryonic development, lung function, wound healing, and cancer progression are close to fluid-to-solid, or ``jamming'' transitions. Theoretical models for confluent 2D tissues have also been shown to exhibit continuous rigidity transitions. However, in vivobiological systems can differ in significant ways from the simple 2D models. For example, many tissues are three-dimensional, mechanically heterogeneous, and/or composed of mechanosensitive cells interspersed with extracellular matrix. We have extended existing models for confluent tissues to capture these features, and we find interesting predictions for collective cell motion that are ultimately related to an underlying generalized jamming transition. For example, in 2D, we find that heterogeneous mixtures of cells spontaneously self-organize into rigid regions of stiffer cells interspersed with string-like groups of soft cells, reminiscent of cellular streaming seen in cancer. We also find that alignment interactions (of the sort often explored in self-propelled particle models) alter the transition and generate interesting flocked liquid and flocked solid collective migration patterns. Our model predicts that 3D tissues also exhibit a jamming transition governed by cell shape, as well as history-dependent aging, and we are currently exploring whether ECM-like interactions in 3D models might help explain compressional stiffening seen in experiments on human tissue.

  3. Use of deep neural network ensembles to identify embryonic-fetal transition markers: repression of COX7A1 in embryonic and cancer cells.

    Science.gov (United States)

    West, Michael D; Labat, Ivan; Sternberg, Hal; Larocca, Dana; Nasonkin, Igor; Chapman, Karen B; Singh, Ratnesh; Makarev, Eugene; Aliper, Alex; Kazennov, Andrey; Alekseenko, Andrey; Shuvalov, Nikolai; Cheskidova, Evgenia; Alekseev, Aleksandr; Artemov, Artem; Putin, Evgeny; Mamoshina, Polina; Pryanichnikov, Nikita; Larocca, Jacob; Copeland, Karen; Izumchenko, Evgeny; Korzinkin, Mikhail; Zhavoronkov, Alex

    2018-01-30

    Here we present the application of deep neural network (DNN) ensembles trained on transcriptomic data to identify the novel markers associated with the mammalian embryonic-fetal transition (EFT). Molecular markers of this process could provide important insights into regulatory mechanisms of normal development, epimorphic tissue regeneration and cancer. Subsequent analysis of the most significant genes behind the DNNs classifier on an independent dataset of adult-derived and human embryonic stem cell (hESC)-derived progenitor cell lines led to the identification of COX7A1 gene as a potential EFT marker. COX7A1 , encoding a cytochrome C oxidase subunit, was up-regulated in post-EFT murine and human cells including adult stem cells, but was not expressed in pre-EFT pluripotent embryonic stem cells or their in vitro -derived progeny. COX7A1 expression level was observed to be undetectable or low in multiple sarcoma and carcinoma cell lines as compared to normal controls. The knockout of the gene in mice led to a marked glycolytic shift reminiscent of the Warburg effect that occurs in cancer cells. The DNN approach facilitated the elucidation of a potentially new biomarker of cancer and pre-EFT cells, the embryo-onco phenotype, which may potentially be used as a target for controlling the embryonic-fetal transition.

  4. Transition metal sensing by Toll-like receptor-4: next to nickel, cobalt and palladium are potent human dendritic cell stimulators

    NARCIS (Netherlands)

    Rachmawati, D.; Bontkes, H.J.; Verstege, M.I.; Muris, J.; von Blomberg, B.M.E.; Scheper, R.J.; van Hoogstraten, I.M.W.

    2013-01-01

    Background Nickel was recently identified as a potent activator of dendritic cells through ligating with human Toll-like receptor (TLR)-4. Objectives Here, we studied an extended panel of transition metals neighbouring nickel in the periodic table of elements, for their capacity to activate human

  5. Overexpression of DOC-1R inhibits cell cycle G1/S transition by repressing CDK2 expression and activation.

    Science.gov (United States)

    Liu, Qi; Liu, Xing; Gao, Jinlan; Shi, Xiuyan; Hu, Xihua; Wang, Shusen; Luo, Yang

    2013-01-01

    DOC-1R (deleted in oral cancer-1 related) is a novel putative tumor suppressor. This study investigated DOC-1R antitumor activity and the underlying molecular mechanisms. Cell phenotypes were assessed using flow cytometry, BrdU incorporation and CDK2 kinase assays in DOC-1R overexpressing HeLa cells. In addition, RT-PCR and Western blot assays were used to detect underlying molecular changes in these cells. The interaction between DOC-1R and CDK2 proteins was assayed by GST pull-down and immunoprecipitation-Western blot assays. The data showed that DOC-1R overexpression inhibited G1/S phase transition, DNA replication and suppressed CDK2 activity. Molecularly, DOC-1R inhibited CDK2 expression at the mRNA and protein levels, and there were decreased levels of G1-phase cyclins (cyclin D1 and E) and elevated levels of p21, p27, and p53 proteins. Meanwhile, DOC-1R associated with CDK2 and inhibited CDK2 activation by obstructing its association with cyclin E and A. In conclusion, the antitumor effects of DOC-1R may be mediated by negatively regulating G1 phase progression and G1/S transition through inhibiting CDK2 expression and activation.

  6. Development of quality indicators for transition from pediatric to adult care in sickle cell disease: A modified Delphi survey of adult providers.

    Science.gov (United States)

    Sobota, Amy E; Shah, Nishita; Mack, Jennifer W

    2017-06-01

    Transition from pediatric to adult care is a vulnerable time for young adults with sickle cell disease (SCD); however, improvements in transition are limited by a lack of quality indicators. The purpose of this study was to establish quality indicators for transition in SCD and to determine the optimal timing between the final pediatric visit and the first adult provider visit. We conducted a modified Delphi survey to reach a consensus on which quality indicators are most important for a successful transition. Our expert panel consisted of members of the Sickle Cell Adult Provider Network. In the first round, the participants ranked a list of quality indicators by importance. In the second round, the participants chose their "top 5" quality indicators in terms of importance and also ranked them on feasibility. The response rates for the two rounds were 68 and 96%, respectively. Nine quality indicators were chosen as "top 5" by a majority of respondents, including communication between pediatric and adult providers, timing of first adult visit, patient self-efficacy, quality of life, and trust with their adult provider. Based on the comments from round 1, respondents were also asked for the optimal timing between leaving pediatric care and entering adult care. Most recommended a first adult visit within 2 months of the final pediatric visit. By using these quality indicators chosen by the majority of respondents, we can better develop and evaluate transition programs for young adults with SCD and improve health outcomes for these vulnerable patients. © 2016 Wiley Periodicals, Inc.

  7. Chimaphilin inhibits human osteosarcoma cell invasion and metastasis through suppressing the TGF-β1-induced epithelial-to-mesenchymal transition markers via PI-3K/Akt, ERK1/2, and Smad signaling pathways.

    Science.gov (United States)

    Dong, Feng; Liu, Tingting; Jin, Hao; Wang, Wenbo

    2018-01-01

    Epithelial-to-mesenchymal transition is a cellular process associated with cancer invasion and metastasis. However, the antimetastatic effects of chimaphilin remain elusive. In this study, we attempted to investigate the potential use of chimaphilin as an inhibitor of TGF-β1-induced epithelial-to-mesenchymal transition in U2OS cells. We found that TGF-β1 induced epithelial-to-mesenchymal transition to promote U2OS cell invasion and metastasis. Western blotting demonstrated that chimaphilin inhibited U2OS cell invasion and migration, increased the expression of the epithelial phenotype marker E-cadherin, repressed the expression of the mesenchymal phenotype marker vimentin, as well as decreased the level of epithelial-to-mesenchymal-inducing transcription factors Snail1 and Slug during the initiation of TGF-β1-induced epithelial-to-mesenchymal transition. In this study, we revealed that chimaphilin up-regulated the E-cadherin expression level and inhibited the production of vimentin, Snail1, and Slug in TGF-β1-induced U2OS cells by blocking PI-3K/Akt and ERK 1/2 signaling pathway. Additionally, the TGF-β1-mediated phosphorylated levels of Smad2/3 were inhibited by chimaphilin pretreatment. Above all, we conclude that chimaphilin represents an effective inhibitor of the metastatic potential of U2OS cells through suppression of TGF-β1-induced epithelial-to-mesenchymal transition.

  8. The SFP1 gene product of Saccharomyces cerevisiae regulates G2/M transitions during the mitotic cell cycle and DNA-damage response

    International Nuclear Information System (INIS)

    Xu, Z.; Norris, D.

    1998-01-01

    In eukaryotic cells, checkpoint pathways arrest cell-cycle progression if a particular event has failed to complete appropriately or if an important intracellular structure is defective or damaged. Saccharomyces cerevisiae strains that lack the SFP1 gene fail to arrest at the G2 DNA-damage checkpoint in response to genomic injury, but maintain their ability to arrest at the replication and spindle-assembly checkpoints. sfp1D mutants are characterized by a premature entrance into mitosis during a normal (undamaged) cell cycle, while strains that overexpress Sfp1p exhibit delays in G2. Sfp1p therefore acts as a repressor of the G2/M transition, both in the normal cell cycle and in the G2 checkpoint pathway. Sfp1 is a nuclear protein with two Cys2His2 zinc-finger domains commonly found in transcription factors. We propose that Sfp1p regulates the expression of gene products involved in the G2/M transition during the mitotic cell cycle and the DNA-damage response. In support of this model, overexpression of Sfp1p induces the expression of the PDS1 gene, which is known to encode a protein that regulates the G2 checkpoint. (author)

  9. Semiclassical analysis of jm → j'm' transitions in rotationally inelastic collisions in cell experiments

    Science.gov (United States)

    Price, T. J.; Hickman, A. P.

    2018-02-01

    Recent quantum calculations of rotationally inelastic collisions of NaK (A1Σ+) with He or Ar in a cell experiment are analyzed using semiclassical approximations valid for large quantum numbers. The results suggest a physical interpretation of jm → j'm' transitions based on the vector model and lead to expressions that explicitly involve the initial and final polar angles of the angular momentum of the target molecule. The relation between the polar angle θ and the azimuthal quantum number m links the semiclassical results for the change in polar angle (θ → θ') to quantum results for an m → m' transition. Analytic formulas are derived that relate the location and width of peaks in the final polar angle distribution (PAD) to the K-dependence of the coefficients dK(j, j'), which are proportional to tensor cross sections σK(j → j'). Several special cases are treated that lead to final PADs that are approximately Lorentzian or sinc functions centered at θ' = θ. Another interesting case, "angular momentum reversal," was observed in the calculations for He. This phenomenon, which involves a reversal of the direction of the target's angular momentum, is shown to be associated with oscillatory behavior of the dK for certain transitions. Finally, several strategies for obtaining the dK coefficients from experimental data are discussed.

  10. Syndecan-1 suppresses epithelial-mesenchymal transition and migration in human oral cancer cells.

    Science.gov (United States)

    Wang, Xiaofeng; He, Jinting; Zhao, Xiaoming; Qi, Tianyang; Zhang, Tianfu; Kong, Chenfei

    2018-04-01

    Epithelial-mesenchymal transition (EMT) is one of the major processes that contribute to the occurrence of cancer metastasis. EMT has been associated with the development of oral cancer. Syndecan‑1 (SDC1) is a key cell‑surface adhesion molecule and its expression level inversely correlates with tumor differentiation and prognosis. In the present study, we aimed to determine the role of SDC1 in oral cancer progression and investigate the molecular mechanisms through which SDC1 regulates the EMT and invasiveness of oral cancer cells. We demonstrated that basal SDC1 expression levels were lower in four oral cancer cell lines (KB, Tca8113, ACC2 and CAL‑27), than in normal human periodontal ligament fibroblasts. Ectopic overexpression of SDC1 resulted in morphological transformation, decreased expression of EMT‑associated markers, as well as decreased migration, invasiveness and proliferation of oral cancer cells. In contrast, downregulation of the expression of SDC1 caused the opposite results. Furthermore, the knockdown of endogenous SDC1 activated the extracellular signal‑regulated kinase (ERK) cascade, upregulated the expression of Snail and inhibited the expression of E‑cadherin. In conclusion, our findings revealed that SDC1 suppressed EMT via the modulation of the ERK signaling pathway that, in turn, negatively affected the invasiveness of human oral cancer cells. Our results provided useful evidence about the potential use of SDC1 as a molecular target for therapeutic interventions in human oral cancer.

  11. MiR-7 triggers cell cycle arrest at the G1/S transition by targeting multiple genes including Skp2 and Psme3.

    Directory of Open Access Journals (Sweden)

    Noelia Sanchez

    Full Text Available MiR-7 acts as a tumour suppressor in many cancers and abrogates proliferation of CHO cells in culture. In this study we demonstrate that miR-7 targets key regulators of the G1 to S phase transition, including Skp2 and Psme3, to promote increased levels of p27(KIP and temporary growth arrest of CHO cells in the G1 phase. Simultaneously, the down-regulation of DNA repair-specific proteins via miR-7 including Rad54L, and pro-apoptotic regulators such as p53, combined with the up-regulation of anti-apoptotic factors like p-Akt, promoted cell survival while arrested in G1. Thus miR-7 can co-ordinate the levels of multiple genes and proteins to influence G1 to S phase transition and the apoptotic response in order to maintain cellular homeostasis. This work provides further mechanistic insight into the role of miR-7 as a regulator of cell growth in times of cellular stress.

  12. Naringenin decreases invasiveness and metastasis by inhibiting TGF-β-induced epithelial to mesenchymal transition in pancreatic cancer cells.

    Directory of Open Access Journals (Sweden)

    Changjie Lou

    Full Text Available Epithelial to mesenchymal transition (EMT promotes cellular motility, invasiveness and metastasis during embryonic development and tumorigenesis. Transforming growth factor-β (TGF-β signaling pathway is a key regulator of EMT. A lot of evidences suggest that this process is Smad3-dependent. Herein we showed that exposure of aspc-1 and panc-1 pancreatic cancer cells to TGF-β1 resulted in characteristic morphological alterations of EMT, and enhancement of cell motility and gemcitabine (Gem resistance along with an up-regulation of EMT markers genes such as vimentin, N-cadherin, MMP2 and MMP9. Naringenin (Nar down-regulated EMT markers expression in both mRNA and protein levels by inhibiting TGF-β1/Smad3 signal pathway in the pancreatic cancer cells. Consequently, Nar suppressed the cells migration and invasion and reversed their resistance to Gem.

  13. Effects of YC-1 on hypoxia-inducible factor 1 alpha in hypoxic human bladder transitional carcinoma cell line T24 cells.

    Science.gov (United States)

    Li, Yangle; Zhao, Xiaokun; Tang, Huiting; Zhong, Zhaohui; Zhang, Lei; Xu, Ran; Li, Songchao; Wang, Yi

    2012-01-01

    It was the aim of this study to explore the effects of 3-(5'-hydroxymethyl-2'-furyl)-l-benzyl indazole (YC-1) on transcription activity, cell proliferation and apoptosis of hypoxic human bladder transitional carcinoma cells (BTCC), mediated by hypoxia-inducible factor 1α (HIF-1α). BTCC cell line T24 cells were incubated under normoxic or hypoxic conditions, adding different doses of YC-1. The protein expression of HIF-1α and HIF-1α-mediated genes was detected by Western blotting. RT-PCR was used to detect HIF-1α mRNA expression. Cell proliferation, apoptosis and migration activity were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry and transwell migration assay. The cells were pretreated by two ERK/p38 MAPK pathway-specific inhibitors, PD98059 or SB203580, and then incubated with YC-1 treatment under hypoxic condition. HIF-1α protein expression was detected by Western blotting. Hypoxic T24 cells expressed a higher level of HIF-1α, vascular endothelial growth factor, matrix metalloproteinases-2, B-cell lymphoma/leukemia-2 protein and HIF-1α mRNA compared with normoxic controls, in which the above-mentioned expression was downregulated by YC-1 in a dose-dependent manner. Cell proliferation and migration activity were inhibited while apoptosis was induced by YC-1 under hypoxic condition. Moreover, YC-1-downregulated HIF-1α expression was reversed by PD98059 and SB203580, respectively. YC-1 inhibits HIF-1α and HIF-1α-mediated gene expression, cell proliferation and migration activity and induces apoptosis in hypoxic BTCC. The ERK/p38 MAPK pathway may be involved in YC-1-mediated inhibition of HIF-1α. Copyright © 2011 S. Karger AG, Basel.

  14. Effect of shear strain on the α-ε phase transition of iron: a new approach in the rotational diamond anvil cell

    International Nuclear Information System (INIS)

    Ma Yanzhang; Selvi, Emre; Levitas, Valery I; Hashemi, Javad

    2006-01-01

    The effect of shear strain on the iron α-ε phase transformation has been studied using a rotational diamond anvil cell (RDAC). The initial transition is observed to take place at the reduced pressure of 10.8 GPa under pressure and shear operation. Complete phase transformation was observed at 15.4 GPa. The rotation of an anvil causes limited pressure elevation and makes the pressure distribution symmetric in the sample chamber before the phase transition. However, it causes a significant pressure increase at the centre of the sample and brings about a large pressure gradient during the phase transformation. The resistance to the phase interface motion is enhanced due to strain hardening during the pressure and shear operations on iron and this further increases the transition pressure. The work of macroscopic shear stress and the work of the pressure and shear stress at the defect tips account for the pressure reduction of the iron phase transition

  15. Mesenchymal to Epithelial Transition Mediated by CDH1 Promotes Spontaneous Reprogramming of Male Germline Stem Cells to Pluripotency

    Directory of Open Access Journals (Sweden)

    Junhui An

    2017-02-01

    Full Text Available Cultured spermatogonial stem cells (GSCs can spontaneously form pluripotent cells in certain culture conditions. However, GSC reprogramming is a rare event that is largely unexplained. We show GSCs have high expression of mesenchymal to epithelial transition (MET suppressors resulting in a developmental barrier inhibiting GSC reprogramming. Either increasing OCT4 or repressing transforming growth factor β (TGF-β signaling promotes GSC reprogramming by upregulating CDH1 and boosting MET. Reducing ZEB1 also enhances GSC reprogramming through its direct effect on CDH1. RNA sequencing shows that rare GSCs, identified as CDH1+ after trypsin digestion, are epithelial-like cells. CDH1+ GSCs exhibit enhanced reprogramming and become more prevalent during the course of reprogramming. Our results provide a mechanistic explanation for the spontaneous emergence of pluripotent cells from GSC cultures; namely, rare GSCs upregulate CDH1 and initiate MET, processes normally kept in check by ZEB1 and TGF-β signaling, thereby ensuring germ cells are protected from aberrant acquisition of pluripotency.

  16. Octamer-binding protein 4 affects the cell biology and phenotypic transition of lung cancer cells involving β-catenin/E-cadherin complex degradation.

    Science.gov (United States)

    Chen, Zhong-Shu; Ling, Dong-Jin; Zhang, Yang-De; Feng, Jian-Xiong; Zhang, Xue-Yu; Shi, Tian-Sheng

    2015-03-01

    Clinical studies have reported evidence for the involvement of octamer‑binding protein 4 (Oct4) in the tumorigenicity and progression of lung cancer; however, the role of Oct4 in lung cancer cell biology in vitro and its mechanism of action remain to be elucidated. Mortality among lung cancer patients is more frequently due to metastasis rather than their primary tumors. Epithelial‑mesenchymal transition (EMT) is a prominent biological event for the induction of epithelial cancer metastasis. The aim of the present study was to investigate whether Oct4 had the capacity to induce lung cancer cell metastasis via the promoting the EMT in vitro. Moreover, the effect of Oct4 on the β‑catenin/E‑cadherin complex, associated with EMT, was examined using immunofluorescence and immunoprecipitation assays as well as western blot analysis. The results demonstrated that Oct4 enhanced cell invasion and adhesion accompanied by the downregulation of epithelial marker cytokeratin, and upregulation of the mesenchymal markers vimentin and N‑cadherin. Furthermore, Oct4 induced EMT of lung cancer cells by promoting β‑catenin/E‑cadherin complex degradation and regulating nuclear localization of β‑catenin. In conclusion, the present study indicated that Oct4 affected the cell biology of lung cancer cells in vitro through promoting lung cancer cell metastasis via EMT; in addition, the results suggested that the association and degradation of the β‑catenin/E‑cadherin complex was regulated by Oct4 during the process of EMT.

  17. Kaempferol, a phytoestrogen, suppressed triclosan-induced epithelial-mesenchymal transition and metastatic-related behaviors of MCF-7 breast cancer cells.

    Science.gov (United States)

    Lee, Geum-A; Choi, Kyung-Chul; Hwang, Kyung-A

    2017-01-01

    As a phytoestrogen, kaempferol is known to play a chemopreventive role inhibiting carcinogenesis and cancer progression. In this study, the influences of triclosan, an anti-bacterial agent recently known for an endocrine disrupting chemical (EDC), and kaempferol on breast cancer progression were examined by measuring their effects on epithelial-mesenchymal transition (EMT) and metastatic-related behaviors of MCF-7 breast cancer cells. Morphological changes of MCF-7 cells were observed, and a wound-healing assay was performed after the treatment of triclosan and kaempferol. The effects of triclosan and kaempferol on protein expression of EMT-related markers such as E-cadherin, N-cadherin, Snail, and Slug and metastasis-related markers such as cathepsin B, D, MMP-2 and -9 were investigated by Western blot assay. In microscopic observations, triclosan (10 -6 M) or E2 (10 -9 M) induced transition to mesenchymal phenotype of MCF-7 cells compared with the control. Co-treatment of ICI 182,780 (10 -8 M), an ER antagonist, or kaempferol (25μM) with E2 or triclosan restored the cellular morphology to an epithelial phenotype. In a wound-healing scratch and a transwell migration assay, triclosan enhanced migration and invasion of MCF-7 cells, but co-treatment of kaempferol or ICI 182,780 reduced the migration and invasion ability of MCF-7 cells to the control level. In addition, kaempferol effectively suppressed E2 or triclosan-induced protein expressions of EMT and metastasis promoting markers. Taken together, triclosan may be a distinct xenoestrogenic EDC to promote EMT, migration, and invasion of MCF-7 breast cancer cells through ER. On the other hand, kaempferol can be an alternative chemopreventive agent to effectively suppress the metastatic behavior of breast cancer induced by an endogenous estrogen as well as exogenous xenoestrogenic compounds including triclosan. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Epithelial-mesenchymal transition: Understanding the basic concept

    Directory of Open Access Journals (Sweden)

    Suresh Babu Ghanta

    2012-01-01

    Full Text Available The epithelial-mesenchymal transition (EMT is described as a rapid and reversible process of change of cell phenotype seen during embryonic development, organ fibrosis, and tumor progression. EMT was first described by Gary Greenberg and Elizabeth Hay in 1982. During EMT the epithelial cells alter their cell polarity, reorganize their cytoskeleton thus become isolated and motile. Depending upon the biological context in which they occur, EMT is divided into three types namely EMT type I, II, III. The article describes the process of EMT implicated in the oral cavity as in palate and root development (type I EMT, gingival fibromatosis and oral sub-mucous fibrosis (type II EMT, and oral squamous cell carcinoma (type III EMT. The reverse process of EMT is called as mesenchymal-epithelial transition seen in association with kidney formation.

  19. Mitochondrial morphology transitions and functions: implications for retrograde signaling?

    Science.gov (United States)

    Picard, Martin; Shirihai, Orian S.; Gentil, Benoit J.

    2013-01-01

    In response to cellular and environmental stresses, mitochondria undergo morphology transitions regulated by dynamic processes of membrane fusion and fission. These events of mitochondrial dynamics are central regulators of cellular activity, but the mechanisms linking mitochondrial shape to cell function remain unclear. One possibility evaluated in this review is that mitochondrial morphological transitions (from elongated to fragmented, and vice-versa) directly modify canonical aspects of the organelle's function, including susceptibility to mitochondrial permeability transition, respiratory properties of the electron transport chain, and reactive oxygen species production. Because outputs derived from mitochondrial metabolism are linked to defined cellular signaling pathways, fusion/fission morphology transitions could regulate mitochondrial function and retrograde signaling. This is hypothesized to provide a dynamic interface between the cell, its genome, and the fluctuating metabolic environment. PMID:23364527

  20. Regulation of matrix stiffness on the epithelial-mesenchymal transition of breast cancer cells under hypoxia environment

    Science.gov (United States)

    Lv, Yonggang; Chen, Can; Zhao, Boyuan; Zhang, Xiaomei

    2017-06-01

    Substrate stiffness and hypoxia are associated with tumor development and progression, respectively. However, the synergy of them on the biological behavior of human breast cancer cell is still largely unknown. This study explored how substrate stiffness regulates the cell phenotype, viability, and epithelial-mesenchymal transition (EMT) of human breast cancer cells MCF-7 under hypoxia (1% O2). TRITC-phalloidin staining showed that MCF-7 cells transformed from round to irregular polygon with stiffness increase either in normoxia or hypoxia. While being accompanied with the upward tendency from a 0.5- to a 20-kPa substrate, the percentage of cell apoptosis was significantly higher in hypoxia than that in normoxia, especially on the 20-kPa substrate. Additionally, it was hypoxia, but not normoxia, that promoted the EMT of MCF-7 by upregulating hypoxia-inducible factor-1α (HIF-1α), vimentin, Snail 1, and matrix metalloproteinase 2 (MMP 2) and 9 (MMP 9), and downregulating E-cadherin simultaneously regardless of the change of substrate stiffness. In summary, this study discovered that hypoxia and stiffer substrate (20 kPa) could synergistically induce phenotype change, apoptosis, and EMT of MCF-7 cells. Results of this study have an important significance on further exploring the synergistic effect of stiffness and hypoxia on the EMT of breast cancer cells and its molecular mechanism.