Science.gov

Sample records for plant maintenance organizations

  1. School Plant Management: Organizing the Maintenance Program. Bulletin, 1960, No. 15. OE-21002

    ERIC Educational Resources Information Center

    Finchum, R. N.

    1960-01-01

    Present capital outlay investments in elementary and secondary school buildings, sites, and equipment in the United States are being increased at the rate of about $3 billion annually. Maintenance and operational services, important aspects of property protection, educational progress, pupil safety, and plant efficiency, are being provided in…

  2. The Health Maintenance Organization

    ERIC Educational Resources Information Center

    Lum, Doman

    1973-01-01

    Controversial proposals to establish health organizations could drastically change the delivery of health services. Understanding the issues in this controversy can help professionals in the human services see what is needed in health reform and legislation. (Author)

  3. Optimization of nuclear plant preventive maintenance

    SciTech Connect

    McClymonds, S.L.; Winge, D.E.

    1987-01-01

    It is generally accepted that preventive maintenance can achieve greater equipment reliability. Most would also agree that the taking of precautions and checking reduces the need to perform corrective maintenance. In the nuclear industry, however, preventive maintenance has not been completely successful in sustaining equipment reliability levels. This paper presents methods for developing an optimum preventive maintenance program for nuclear power plants, one which will contribute to high plant availability by concentrating resources on those maintenance tasks that are directly applicable to equipment reliability.

  4. Physician Incentives in Health Maintenance Organizations

    ERIC Educational Resources Information Center

    Gaynor, Martin; Rebitzer, James B.; Taylor, Lowell J.

    2004-01-01

    Managed care organizations rely on incentives that encourage physicians to limit medical expenditures, but little is known about how physicians respond to these incentives. We address this issue by analyzing the physician incentive contracts in use at a health maintenance organization. By combining knowledge of the incentive contracts with…

  5. Plant maintenance and advanced reactors, 2006

    SciTech Connect

    Agnihotri, Newal

    2006-09-15

    The focus of the September-October issue is on plant maintenance and advanced reactors. Major articles/reports in this issue include: Advanced plants to meet rising expectations, by John Cleveland, International Atomic Energy Agency, Vienna; A flexible and economic small reactor, by Mario D. Carelli and Bojan Petrovic, Westinghouse Electric Company; A simple and passively safe reactor, by Yury N. Kuznetsov, Research and Development Institute of Power Engineering (NIKIET), Russia; Gas-cooled reactors, by Jeffrey S. Merrifield, U.S. Nuclear Regulatory Commission; ISI project managment in the PRC, by Chen Chanbing, RINPO, China; and, Fort Calhoun refurbishment, by Sudesh Cambhir, Omaha Public Power District.

  6. Plant maintenance and advanced reactors, 2007

    SciTech Connect

    Agnihotri, Newal

    2007-09-15

    The focus of the September-October issue is on plant maintenance and advanced reactors. Major articles/reports in this issue include: A new day for energy in America; Committed to success more than ever, by Andy White, GE--Hitachi Nuclear Energy; Competitive technology for decades, by Steve Tritch, Westinghouse Electric Company; Pioneers of positive community relationship, by Exelon Nuclear; A robust design for 60-years, by Ray Ganthner, Areva; Aiming at no evacuation plants, by Kumiaki Moriya, Hitachi-GE Nuclear Energy, Ltd.; and, Desalination and hydrogen economy, by Dr. I. Khamis, International Atomic Energy Agency. Industry innovation articles in this issue are: Reactor vessel closure head project, by Jeff LeClair, Prairie Island Nuclear Generating Plant; and Submersible remote-operated vehicle, by Michael S. Rose, Entergy's Fitzpatrick Nuclear Station.

  7. Plant Regulatory Organizations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chapter on Plant Regulatory Organizations is part of a book titled Pest Management and Phytosanitary Trade Barriers authored by Neil Heather (Australia) and Guy Hallman. It covers the role of plant regulatory organizations from the international to state level in protecting plant health. At on...

  8. Plant maintenance and plant life extension issue, 2007

    SciTech Connect

    Agnihotri, Newal

    2007-03-15

    The focus of the March-April issue is on plant maintenance and plant life extension. Major articles/reports in this issue include: Three proposed COLs expected in 2007, by Dale E. Klein, U.S. Nuclear Regulatory Commission; Delivering behaviors that our customers value, by Jack Allen, Westinghouse Electric Company; Facilitating high-level and fuel waste disposal technologies, by Malcolm Gray, IAEA, Austria; Plant life management and long-term operation, by Pal Kovacs, OECD-NEA, France; Measuring control rod position, by R. Taymanov, K. Sapozhnikova, I. Druzhinin, D.I. Mendeleyev, Institue for Metrology, Russia; and, 'Modernization' means higher safety, by Svetlana Genova, Kozluduy NPP plc, Bulgaria.

  9. Plant maintenance and advanced reactors issue, 2008

    SciTech Connect

    Agnihotri, Newal

    2009-09-15

    The focus of the September-October issue is on plant maintenance and advanced reactors. Major articles/reports in this issue include: Technologies of national importance, by Tsutomu Ohkubo, Japan Atomic Energy Agency, Japan; Modeling and simulation advances brighten future nuclear power, by Hussein Khalil, Argonne National Laboratory, Energy and desalination projects, by Ratan Kumar Sinha, Bhabha Atomic Research Centre, India; A plant with simplified design, by John Higgins, GE Hitachi Nuclear Energy; A forward thinking design, by Ray Ganthner, AREVA; A passively safe design, by Ed Cummins, Westinghouse Electric Company; A market-ready design, by Ken Petrunik, Atomic Energy of Canada Limited, Canada; Generation IV Advanced Nuclear Energy Systems, by Jacques Bouchard, French Commissariat a l'Energie Atomique, France, and Ralph Bennett, Idaho National Laboratory; Innovative reactor designs, a report by IAEA, Vienna, Austria; Guidance for new vendors, by John Nakoski, U.S. Nuclear Regulatory Commission; Road map for future energy, by John Cleveland, International Atomic Energy Agency, Vienna, Austria; and, Vermont's largest source of electricity, by Tyler Lamberts, Entergy Nuclear Operations, Inc. The Industry Innovation article is titled Intelligent monitoring technology, by Chris Demars, Exelon Nuclear.

  10. Report on the Maintenance Division and School Plant Operations.

    ERIC Educational Resources Information Center

    Seitz, Charles A.; And Others

    The Division of Maintenance of the Montgomery County (MD) Public Schools (MCPS) is responsible for the maintenance and repair of all buildings, equipment, grounds, and facilities. School Plant Operations is not an administrative unit, but a function which includes the operation of plant equipment and custodial and housekeeping services. After an…

  11. Spare parts inventory risk for decision making in plant maintenance

    NASA Astrophysics Data System (ADS)

    Sharif, Kamal Imran; Ibrahim, Jafni Azhan; Udin, Zulkifli Mohamed

    2016-08-01

    Equipment breakdown due to unavailability of spare parts is really disastrous in plant maintenance. The failure increase the cost of repair and production downtime. Therefore, it is important to understand the maintenance and inventory function in order to ensure the plant operate accordingly. Moreover, it is necessary for the plant maintenance to balance the issue of shortage and excess of inventory in plant maintenance. In view of this situation, the spare parts become a critical matters and it is good starting point to tackle the issues from looking at the perspective of spare parts inventory risk. This paper describes the development of risk technique for plant maintenance decision making purposes using the Shortage and Excess Impact Table. It also used the Breakdown Probability Table to quantify the risk for the spare part failure.

  12. 14 CFR 91.1423 - CAMP: Maintenance organization.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false CAMP: Maintenance organization. 91.1423... Operations Program Management § 91.1423 CAMP: Maintenance organization. (a) Each program manager who... the performance of that work, must have an organization adequate to perform the work. (b) Each...

  13. 14 CFR 91.1423 - CAMP: Maintenance organization.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false CAMP: Maintenance organization. 91.1423... Operations Program Management § 91.1423 CAMP: Maintenance organization. (a) Each program manager who... the performance of that work, must have an organization adequate to perform the work. (b) Each...

  14. 14 CFR 91.1423 - CAMP: Maintenance organization.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false CAMP: Maintenance organization. 91.1423... Operations Program Management § 91.1423 CAMP: Maintenance organization. (a) Each program manager who... the performance of that work, must have an organization adequate to perform the work. (b) Each...

  15. 14 CFR 91.1423 - CAMP: Maintenance organization.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false CAMP: Maintenance organization. 91.1423... Operations Program Management § 91.1423 CAMP: Maintenance organization. (a) Each program manager who... the performance of that work, must have an organization adequate to perform the work. (b) Each...

  16. Review of maintenance personnel practices at nuclear power plants

    SciTech Connect

    Chockie, A.D.; Badalamente, R.V.; Hostick, C.J.; Vickroy, S.C.; Bryant, J.L.; Imhoff, C.H.

    1984-05-01

    As part of the Nuclear Regulatory Commission (NRC) sponsored Maintenance Qualifications and Staffing Project, the Pacific Northwest Laboratory (PNL) has conducted a preliminary assessment of nuclear power plant (NPP) maintenance practices. As requested by the NRC, the following areas within the maintenance function were examined: personnel qualifications, maintenance training, overtime, shiftwork and staffing levels. The purpose of the assessment was to identify the primary safety-related problems that required further analysis before specific recommendations can be made on the regulations affecting NPP maintenance operations.

  17. School Plant Maintenance and Custodial Services

    ERIC Educational Resources Information Center

    Kentucky State Dept. of Education, Frankfort.

    School maintenance guidelines are directed to the local school situation where the custodian may have neither the opportunity for any formal training or experienced personnel available to instruct him. Topics covered are those that are thought to be of greatest value to the local school custodian and include--(1) floor care, (2) carpet cleaning,…

  18. Davis PV plant operation and maintenance manual

    SciTech Connect

    1994-09-01

    This operation and maintenance manual contains the information necessary to run the Photovoltaics for Utility Scale Applications (PVUSA) test facility in Davis, California. References to more specific information available in drawings, data sheets, files, or vendor manuals are included. The PVUSA is a national cooperative research and demonstration program formed in 1987 to assess the potential of utility scale photovoltaic systems.

  19. 14 CFR 121.365 - Maintenance, preventive maintenance, and alteration organization.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... alteration organization. 121.365 Section 121.365 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... organization. (a) Each certificate holder that performs any of its maintenance (other than required inspections... work must have an organization adequate to perform the work. (b) Each certificate holder that...

  20. 14 CFR 121.365 - Maintenance, preventive maintenance, and alteration organization.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... alteration organization. 121.365 Section 121.365 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... organization. (a) Each certificate holder that performs any of its maintenance (other than required inspections... work must have an organization adequate to perform the work. (b) Each certificate holder that...

  1. 14 CFR 121.365 - Maintenance, preventive maintenance, and alteration organization.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... alteration organization. 121.365 Section 121.365 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... organization. (a) Each certificate holder that performs any of its maintenance (other than required inspections... work must have an organization adequate to perform the work. (b) Each certificate holder that...

  2. 14 CFR 135.423 - Maintenance, preventive maintenance, and alteration organization.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... alteration organization. 135.423 Section 135.423 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION..., preventive maintenance, and alteration organization. (a) Each certificate holder that performs any of its... whom it arranges for the performance of that work, must have an organization adequate to perform...

  3. 14 CFR 121.365 - Maintenance, preventive maintenance, and alteration organization.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... alteration organization. 121.365 Section 121.365 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... organization. (a) Each certificate holder that performs any of its maintenance (other than required inspections... work must have an organization adequate to perform the work. (b) Each certificate holder that...

  4. 14 CFR 135.423 - Maintenance, preventive maintenance, and alteration organization.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... alteration organization. 135.423 Section 135.423 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION..., preventive maintenance, and alteration organization. (a) Each certificate holder that performs any of its... whom it arranges for the performance of that work, must have an organization adequate to perform...

  5. 14 CFR 121.365 - Maintenance, preventive maintenance, and alteration organization.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... alteration organization. 121.365 Section 121.365 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... organization. (a) Each certificate holder that performs any of its maintenance (other than required inspections... work must have an organization adequate to perform the work. (b) Each certificate holder that...

  6. 14 CFR 135.423 - Maintenance, preventive maintenance, and alteration organization.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... alteration organization. 135.423 Section 135.423 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION..., preventive maintenance, and alteration organization. (a) Each certificate holder that performs any of its... whom it arranges for the performance of that work, must have an organization adequate to perform...

  7. 14 CFR 135.423 - Maintenance, preventive maintenance, and alteration organization.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... alteration organization. 135.423 Section 135.423 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION..., preventive maintenance, and alteration organization. (a) Each certificate holder that performs any of its... whom it arranges for the performance of that work, must have an organization adequate to perform...

  8. 14 CFR 135.423 - Maintenance, preventive maintenance, and alteration organization.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... alteration organization. 135.423 Section 135.423 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION..., preventive maintenance, and alteration organization. (a) Each certificate holder that performs any of its... whom it arranges for the performance of that work, must have an organization adequate to perform...

  9. Just In-Time Maintenance of Nuclear Power Plants

    SciTech Connect

    DR. Alexander G. Parlos

    2002-01-22

    The goal of this project has been to develop and demonstrate the feasibility of a new technology for maintenance engineering: a Just-In-Time Maintenance (JITM) system for rotating machines. The JITM system is based on several key developments at Texas A and M over the past ten years in emerging intelligent information technologies, which if integrated into a single system could provide a revolutionary approach in the way maintenance is performed. Rotating machines, such as induction motors, range from a few horse power (hp) to several thousand hp in size, and they are widely used in nuclear power plants and in other industries. Forced outages caused by induction motor failures are the reason for as much as 15% - 40% of production costs to be attributable to maintenance, whereas plant shutdowns caused by induction motor failures result in daily financial losses to the utility and process industries of $1 M or more. The basic components of the JITM system are the available machine sensors, that is electric current sensors and accelerometers, and the computational algorithms used in the analysis and interpretation of the occurring incipient failures. The JITM system can reduce the costs attributable to maintenance by about 40% and it can lower the maintenance budgets of power and process plants by about 35%, while requiring no additional sensor installation. As a result, the JITM system can improve the competitiveness of US nuclear utilities at minimal additional cost.

  10. Development of plant maintenance management system (pmms): a case study

    NASA Astrophysics Data System (ADS)

    Che Azhar, N. A.; Mansor, M. A.

    2013-12-01

    In large plant industry, it is not easy to maintain machine performance without using any method such as checklist system. Manual checklist is a common maintenance checklist used in industry. All machine, equipment and parts that need to be checked will be written down for the employee to do maintenance checks. Converting the manual checklist to the Plant Maintenance Management System (PMMS) can improve the way of employees work and make plant management easier. Therefore, a new system was designed to maintain the equipment so that the activities are more efficient and cost effective. The system consists of three frames that connect to each other. The frames divide to section, equipment and checklist. This system also builds to prevent data from arbitrarily changes. Only certain officers or staffs are permitted to make modifications to data. Using this system, a company can make the office environment a paperless environment.

  11. Plant maintenance and aging management: Are they the same?

    SciTech Connect

    Lofaro, R.J.

    1995-06-01

    As part of the NRC`s Nuclear Plant Aging Research Program, a number of aging studies were performed on safety-related systems and components which found that, even with current maintenance and monitoring practices in place, a large number of the reported failures are related to aging. This suggests that current practices are not sufficient to completely manage aging degradation, and other factors need to be considered. This paper examines the aging management process and the degree to which maintenance plays a part in it. Component failures and degradation mechanisms identified in aging studies of several different safety systems are summarized and evaluated, then con-elated with the components most frequently failed. This information, along with an analysis of failure causes, is then used to determine the extent to which aging is managed by current maintenance practices. Conclusions and recommendations for proper aging management arc also presented.

  12. Behavioral Groups as Preventive Care in a Health Maintenance Organization.

    ERIC Educational Resources Information Center

    Shapiro, Joan; And Others

    This paper describes the use of a particular therapeutic modality--behavioral groups--in a relatively new delivery system called a Health Maintenance Organization. The program described, run under the George Washington University Health Plan, offers short-term structured groups designed to aid people at particularly difficult or vulnerable…

  13. 14 CFR 91.1423 - CAMP: Maintenance organization.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false CAMP: Maintenance organization. 91.1423 Section 91.1423 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional Ownership Operations Program Management § 91.1423...

  14. Advanced maintenance, inspection & repair technology for nuclear power plants

    SciTech Connect

    Hinton, B.M.

    1994-12-31

    Maintenance, inspection, and repair technology for nuclear power plants is outlined. The following topics are discussed: technology for reactor systems, reactor refueling bridge, fuel inspection system, fuel shuffling software, fuel reconstitution, CEA/RCCA/CRA inspection, vessel inspection capabilities, CRDM inspection and repair, reactor internals inspection and repair, stud tensioning system, stud/nut cleaning system, EDM machining technology, MI Cable systems, core exit T/C nozzle assemblies, technology for steam generators, genesis manipulator systems, ECT, UT penetrant inspections, steam generator repair and cleaning systems, technology for balance of plant, heat exchangers, piping and weld inspections, and turbogenerators.

  15. 76 FR 55137 - Monitoring the Effectiveness of Maintenance at Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-06

    ... COMMISSION Monitoring the Effectiveness of Maintenance at Nuclear Power Plants AGENCY: Nuclear Regulatory..., ``Monitoring the Effectiveness of Maintenance at Nuclear Power Plants.'' This guide endorses Revision 4A to... Effectiveness of Maintenance at Nuclear Power Plants,'' which provides methods that are acceptable to the...

  16. Inertial Fusion Power Plant Concept of Operations and Maintenance

    SciTech Connect

    Anklam, T.; Knutson, B.; Dunne, A. M.; Kasper, J.; Sheehan, T.; Lang, D.; Roberts, V.; Mau, D.

    2015-01-15

    Parsons and LLNL scientists and engineers performed design and engineering work for power plant pre-conceptual designs based on the anticipated laser fusion demonstrations at the National Ignition Facility (NIF). Work included identifying concepts of operations and maintenance (O&M) and associated requirements relevant to fusion power plant systems analysis. A laser fusion power plant would incorporate a large process and power conversion facility with a laser system and fusion engine serving as the heat source, based in part on some of the systems and technologies advanced at NIF. Process operations would be similar in scope to those used in chemical, oil refinery, and nuclear waste processing facilities, while power conversion operations would be similar to those used in commercial thermal power plants. While some aspects of the tritium fuel cycle can be based on existing technologies, many aspects of a laser fusion power plant presents several important and unique O&M requirements that demand new solutions. For example, onsite recovery of tritium; unique remote material handling systems for use in areas with high radiation, radioactive materials, or high temperatures; a five-year fusion engine target chamber replacement cycle with other annual and multi-year cycles anticipated for major maintenance of other systems, structures, and components (SSC); and unique SSC for fusion target waste recycling streams. This paper describes fusion power plant O&M concepts and requirements, how O&M requirements could be met in design, and how basic organizational and planning issues can be addressed for a safe, reliable, economic, and feasible fusion power plant.

  17. Inertial fusion power plant concept of operations and maintenance

    NASA Astrophysics Data System (ADS)

    Knutson, Brad; Dunne, Mike; Kasper, Jack; Sheehan, Timothy; Lang, Dwight; Anklam, Tom; Roberts, Valerie; Mau, Derek

    2015-02-01

    Parsons and LLNL scientists and engineers performed design and engineering work for power plant pre-conceptual designs based on the anticipated laser fusion demonstrations at the National Ignition Facility (NIF). Work included identifying concepts of operations and maintenance (O&M) and associated requirements relevant to fusion power plant systems analysis. A laser fusion power plant would incorporate a large process and power conversion facility with a laser system and fusion engine serving as the heat source, based in part on some of the systems and technologies advanced at NIF. Process operations would be similar in scope to those used in chemical, oil refinery, and nuclear waste processing facilities, while power conversion operations would be similar to those used in commercial thermal power plants. While some aspects of the tritium fuel cycle can be based on existing technologies, many aspects of a laser fusion power plant presents several important and unique O&M requirements that demand new solutions. For example, onsite recovery of tritium; unique remote material handling systems for use in areas with high radiation, radioactive materials, or high temperatures; a five-year fusion engine target chamber replacement cycle with other annual and multi-year cycles anticipated for major maintenance of other systems, structures, and components (SSC); and unique SSC for fusion target waste recycling streams. This paper describes fusion power plant O&M concepts and requirements, how O&M requirements could be met in design, and how basic organizational and planning issues can be addressed for a safe, reliable, economic, and feasible fusion power plant.

  18. Case management in the social health maintenance organization demonstrations

    PubMed Central

    Yordi, Cathleen L.

    1988-01-01

    In this article, case management departments and roles during the early years of the social health maintenance organization (S/HMO) demonstrations are compared. These organizations provide acute and chronic care services under a prepaid plan for the elderly. Eligibility criteria for case management and chronic care services at each site are compared, followed by a description of the resultant case mix of members receiving chronic care benefits. Case managers principal activities are described, and a preliminary assessment is made about the strength of the linkages that have been developed between the case management component of these plans and the larger health care system. PMID:10312977

  19. Health maintenance organization environments in the 1980s and beyond

    PubMed Central

    Morrison, Ellen M.; Luft, Harold S.

    1990-01-01

    Throughout the past decade, health maintenance organizations (HMOs) were buffeted by dramatic regulatory and competitive changes. In this article, literature of the 1980s is reviewed to update our knowledge on the HMO industry and to suggest future research. The influence of intensified competition on these organizations and the determinants of market entry, expansion, and exit are examined. These organizations are now beginning to require copayments and deductibles and to offer point-of-service choice, while indemnity plans are developing sophisticated utilization management techniques. Given these significant structural changes, past distinctions among HMO, preferred provider organization and fee-for-service medicine must be replaced with a distinction between degree of provider choice and level of benefits. PMID:10113465

  20. Characterizing and Assessing a Large-Scale Software Maintenance Organization

    NASA Technical Reports Server (NTRS)

    Briand, Lionel; Melo, Walcelio; Seaman, Carolyn; Basili, Victor

    1995-01-01

    One important component of a software process is the organizational context in which the process is enacted. This component is often missing or incomplete in current process modeling approaches. One technique for modeling this perspective is the Actor-Dependency (AD) Model. This paper reports on a case study which used this approach to analyze and assess a large software maintenance organization. Our goal was to identify the approach's strengths and weaknesses while providing practical recommendations for improvement and research directions. The AD model was found to be very useful in capturing the important properties of the organizational context of the maintenance process, and aided in the understanding of the flaws found in this process. However, a number of opportunities for extending and improving the AD model were identified. Among others, there is a need to incorporate quantitative information to complement the qualitative model.

  1. Knowledge elicitation techniques and application to nuclear plant maintenance

    NASA Astrophysics Data System (ADS)

    Doyle, E. Kevin

    The new millennium has brought with it the opportunity of global trade which in turn requires the utmost in efficiency from each individual industry. This includes the nuclear power industry, a point which was emphasized when the electrical generation industry began to be de regulated across North America the late 1990s and re-emphasized when the northeast power grid of North America collapsed in the summer of 2003. This dissertation deals with reducing the cost of the maintenance function of Candu nuclear power plants and initiating a strong link between universities and the Canadian nuclear industry. Various forms of RCM (reliability-centred maintenance) have been the tools of choice in industry for improving the maintenance function during the last 20 years. In this project, pilot studies, conducted at Bruce Power between 1999 and 2005, and reported on in this dissertation, lay out a path to implement statistical improvements as the next step after RCM in reducing the cost of the maintenance. Elicitation protocols, designed for the age group being elicited, address the much-documented issue of a lack of data. Clear, graphical, inferential statistical interfaces are accentuated and developed to aid in building the teams required to implement the various methodologies and to help in achieving funding targets. Graphical analysis and Crow/AMSAA (army materials systems analysis activity) plots are developed and demonstrated from the point of view of justifying the expenditures of cost reduction efforts. This dissertation ultimately speaks to the great opportunity being presented by this approach at this time: of capturing the baby-boom generation's huge pool of knowledge before those people retire. It is expected that the protocols and procedures referenced here will have applicability across the many disciplines where collecting expert information from a similar age group is required.

  2. Budgeting for Solar PV Plant Operations & Maintenance: Practices and Pricing.

    SciTech Connect

    Enbar, Nadav; Weng, Dean; Klise, Geoffrey Taylor

    2016-01-01

    With rising grid interconnections of solar photovoltaic (PV) systems, greater attention is being trained on lifecycle performance, reliability, and project economics. Expected to meet production thresholds over a 20-30 year timeframe, PV plants require a steady diet of operations and maintenance (O&M) oversight to meet contractual terms. However, industry best practices are only just beginning to emerge, and O&M budgets—given the arrangement of the solar project value chain—appear to vary widely. Based on insights from in-depth interviews and survey research, this paper presents an overview of the utility-scale PV O&M budgeting process along with guiding rationales, before detailing perspectives on current plant upkeep activities and price points largely in the U.S. It concludes by pondering potential opportunities for improving upon existing O&M budgeting approaches in ways that can benefit the industry at-large.

  3. Budgeting for Solar PV Plant Operations & Maintenance: Practices and Pricing.

    SciTech Connect

    Enbar, Nadav; Weng, Dean; Klise, Geoffrey Taylor

    2015-12-01

    With rising grid interconnections of solar photovoltaic (PV) systems, greater attention is being trained on lifecycle performance, reliability, and project economics. Expected to meet production thresholds over a 20-30 year timeframe, PV plants require a steady diet of operations and maintenance (O&M) oversight to meet contractual terms. However, industry best practices are only just beginning to emerge, and O&M budgets—given the arrangement of the solar project value chain—appear to vary widely. Based on insights from in-depth interviews and survey research, this paper presents an overview of the utility-scale PV O&M budgeting process along with guiding rationales, before detailing perspectives on current plant upkeep activities and price points largely in the U.S. It concludes by pondering potential opportunities for improving upon existing O&M budgeting approaches in ways that can benefi t the industry at-large.

  4. Selection bias in health maintenance organizations: Analysis of recent evidence

    PubMed Central

    Hellinger, Fred J.

    1987-01-01

    An analysis of recent research regarding selection bias in health maintenance organizations (HMO's) is presented in this article. Review of the available literature leads one to conclude that prepaid group practice HMO's do experience favorable selection. It has been demonstrated in numerous studies that prior use of health services by HMO enrollees is less than prior use of health services by those who remain in the fee-for-service sector, and there is considerable evidence that shows a statistically significant positive relationship between prior use and current use. This is true for both those under 65 years of age and those 65 years of age or over. PMID:10312393

  5. Alternative geographic configurations for Medicare payments to health maintenance organizations.

    PubMed

    Porell, F W; Tompkins, C P; Turner, W M

    1990-01-01

    Under prevailing legislation, Medicare payments to health maintenance organizations (HMOs) are based upon projected fee-for-service reimbursement levels for enrollees' county of residence. These rates have been criticized in light of substantial variations in rates among neighboring counties and large fluctuations in rates over time. In this study, the use of nine alternative configurations and the county itself were evaluated on the basis of payment-area homogeneity, payment rate stability, and policy criteria, including the fiscal impacts of reconfiguration on HMOs. The results revealed rather modest differences among most alternative configurations and do not lend strong support for payment area reconfiguration at this time. PMID:10113270

  6. Effect of Mergers on Health Maintenance Organization Premiums

    PubMed Central

    Feldman, Roger; Wholey, Douglas; Christianson, Jon

    1996-01-01

    This study estimated the effect of mergers on health maintenance organization (HMO) premiums, using data on all operational non-Medicaid HMOs in the United States from 1985 to 1993. Two critical issues were examined: whether HMO mergers increase or decrease premiums; and whether the effects of mergers differ according to the degree of competition among HMOs in local markets. The only significant merger effect was found in the most competitive markets, where premiums increased, but only for 1 year after the merger. Our research does not support the argument that consolidation of HMOs in local markets will benefit consumers through lower premiums. PMID:10158729

  7. Stability of frailty in the social/health maintenance organization.

    PubMed

    Hallfors, D; Leutz, W; Capitman, J; Ritter, G

    1994-01-01

    Although many long-term care (LTC) programs assume that the disabilities of their frail elderly participants are stable in nature, there has been suggestive evidence to the contrary. This study tests stability of disability among social/health maintenance organization (S/HMO) members who were judged eligible for admission into a nursing home. Identified persons were reassessed quarterly. By the end of 1 year, less than 50 percent were still considered to be nursing home eligible. Logit analysis revealed an increased likelihood of instability for persons who were newly identified as functionally disabled after hospitalization. Policy implications for capitated managed-care programs for the elderly are discussed. PMID:10138480

  8. DNA maintenance in plastids and mitochondria of plants

    PubMed Central

    Oldenburg, Delene J.; Bendich, Arnold J.

    2015-01-01

    The DNA molecules in plastids and mitochondria of plants have been studied for over 40 years. Here, we review the data on the circular or linear form, replication, repair, and persistence of the organellar DNA (orgDNA) in plants. The bacterial origin of orgDNA appears to have profoundly influenced ideas about the properties of chromosomal DNA molecules in these organelles to the point of dismissing data inconsistent with ideas from the 1970s. When found at all, circular genome-sized molecules comprise a few percent of orgDNA. In cells active in orgDNA replication, most orgDNA is found as linear and branched-linear forms larger than the size of the genome, likely a consequence of a virus-like DNA replication mechanism. In contrast to the stable chromosomal DNA molecules in bacteria and the plant nucleus, the molecular integrity of orgDNA declines during leaf development at a rate that varies among plant species. This decline is attributed to degradation of damaged-but-not-repaired molecules, with a proposed repair cost-saving benefit most evident in grasses. All orgDNA maintenance activities are proposed to occur on the nucleoid tethered to organellar membranes by developmentally-regulated proteins. PMID:26579143

  9. Inspecting the School Plant. The Operation and Maintenance of Our Schools. Monograph 2. Bulletin No. 6105.

    ERIC Educational Resources Information Center

    Biwer-Al-Yacoubi, Connie

    Two intruments for evaluating the school plant are presented in this monograph. The first enables districts to appraise the effectiveness of school maintenance programs and plan for future maintenance needs. The eight aspects of maintenance covered relate to the exterior of the building, the interior, special classrooms, the electrical system, the…

  10. Patterns of Health Maintenance Organization Service Areas in Rural Counties

    PubMed Central

    Ricketts, Thomas C.; Slifkin, Rebecca T.; Johnson-Webb, Karen D.

    1995-01-01

    This study analyzes the 1993 National Directory of HMOs to determine the extent to which rural counties are included in health maintenance organization (HMO) service areas. Two specific questions are addressed: (1) How do the patterns of service areas differ across HMO model types? (2) What are the characteristics that distinguish rural counties served by HMOs from those that are not? Although a majority of rural counties are in HMO service areas, substantially fewer are served by non-individual practice association (non-IPA) models. Access to HMO services is found to decrease with county population density, and adjacency to metropolitan areas is an important predictor of inclusion in service areas. PMID:10153478

  11. Physician adaptation to health maintenance organizations and implications for management.

    PubMed Central

    Schulz, R; Scheckler, W E; Girard, C; Barker, K

    1990-01-01

    The growth of health maintenance organizations (HMOs) and other forms of managed care presents a challenge to traditional patterns of private practice. In Dane County, Wisconsin (Madison Metropolitan Area), the proportion of the population enrolled in closed-panel HMOs increased dramatically, from 10 percent in 1983 to over 40 percent by 1986. This study surveyed 850 practicing physicians regarding their expectations before, and experiences after this rapid change to competitive HMOs. Although most physicians expected a loss of earnings and lower-quality care, the majority reported that neither declined. However, most physicians expected and reported a decline in their autonomy. Primary care physicians were most supportive of the change to HMOs. The implications of these findings for management practices are discussed. PMID:2329049

  12. Organization and maintenance of molecular domains in myelinated axons.

    PubMed

    Buttermore, Elizabeth D; Thaxton, Courtney L; Bhat, Manzoor A

    2013-05-01

    Over a century ago, Ramon y Cajal first proposed the idea of a directionality involved in nerve conduction and neuronal communication. Decades later, it was discovered that myelin, produced by glial cells, insulated axons with periodic breaks where nodes of Ranvier (nodes) form to allow for saltatory conduction. In the peripheral nervous system (PNS), Schwann cells are the glia that can either individually myelinate the axon from one neuron or ensheath axons of many neurons. In the central nervous system (CNS), oligodendrocytes are the glia that myelinate axons from different neurons. Review of more recent studies revealed that this myelination created polarized domains adjacent to the nodes. However, the molecular mechanisms responsible for the organization of axonal domains are only now beginning to be elucidated. The molecular domains in myelinated axons include the axon initial segment (AIS), where various ion channels are clustered and action potentials are initiated; the node, where sodium channels are clustered and action potentials are propagated; the paranode, where myelin loops contact with the axolemma; the juxtaparanode (JXP), where delayed-rectifier potassium channels are clustered; and the internode, where myelin is compactly wrapped. Each domain contains a unique subset of proteins critical for the domain's function. However, the roles of these proteins in axonal domain organization are not fully understood. In this review, we highlight recent advances on the molecular nature and functions of some of the components of each axonal domain and their roles in axonal domain organization and maintenance for proper neuronal communication. PMID:23404451

  13. Cellular mechanisms for cargo delivery and polarity maintenance at different polar domains in plant cells

    PubMed Central

    Łangowski, Łukasz; Wabnik, Krzysztof; Li, Hongjiang; Vanneste, Steffen; Naramoto, Satoshi; Tanaka, Hirokazu; Friml, Jiří

    2016-01-01

    The asymmetric localization of proteins in the plasma membrane domains of eukaryotic cells is a fundamental manifestation of cell polarity that is central to multicellular organization and developmental patterning. In plants, the mechanisms underlying the polar localization of cargo proteins are still largely unknown and appear to be fundamentally distinct from those operating in mammals. Here, we present a systematic, quantitative comparative analysis of the polar delivery and subcellular localization of proteins that characterize distinct polar plasma membrane domains in plant cells. The combination of microscopic analyses and computational modeling revealed a mechanistic framework common to diverse polar cargos and underlying the establishment and maintenance of apical, basal, and lateral polar domains in plant cells. This mechanism depends on the polar secretion, constitutive endocytic recycling, and restricted lateral diffusion of cargos within the plasma membrane. Moreover, our observations suggest that polar cargo distribution involves the individual protein potential to form clusters within the plasma membrane and interact with the extracellular matrix. Our observations provide insights into the shared cellular mechanisms of polar cargo delivery and polarity maintenance in plant cells. PMID:27462465

  14. Cellular mechanisms for cargo delivery and polarity maintenance at different polar domains in plant cells.

    PubMed

    Łangowski, Łukasz; Wabnik, Krzysztof; Li, Hongjiang; Vanneste, Steffen; Naramoto, Satoshi; Tanaka, Hirokazu; Friml, Jiří

    2016-01-01

    The asymmetric localization of proteins in the plasma membrane domains of eukaryotic cells is a fundamental manifestation of cell polarity that is central to multicellular organization and developmental patterning. In plants, the mechanisms underlying the polar localization of cargo proteins are still largely unknown and appear to be fundamentally distinct from those operating in mammals. Here, we present a systematic, quantitative comparative analysis of the polar delivery and subcellular localization of proteins that characterize distinct polar plasma membrane domains in plant cells. The combination of microscopic analyses and computational modeling revealed a mechanistic framework common to diverse polar cargos and underlying the establishment and maintenance of apical, basal, and lateral polar domains in plant cells. This mechanism depends on the polar secretion, constitutive endocytic recycling, and restricted lateral diffusion of cargos within the plasma membrane. Moreover, our observations suggest that polar cargo distribution involves the individual protein potential to form clusters within the plasma membrane and interact with the extracellular matrix. Our observations provide insights into the shared cellular mechanisms of polar cargo delivery and polarity maintenance in plant cells. PMID:27462465

  15. Managing aging in nuclear power plants: Insights from NRC`s Maintenance Team Inspection reports

    SciTech Connect

    Fresco, A.; Subudhi, M.

    1992-12-31

    A plant`s maintenance program is the principal vehicle through which age-related degradation is managed. From 1988 to 1991, the NRC evaluated the maintenance program of every nuclear power plant in the United States. Forty-four out of a total of sixty-seven of the reports issued on these in-depth team inspections have been reviewed for insights into the strengths and weaknesses of the programs as related to the need to understand and manage the effects of aging on nuclear plant structures, systems, and components (SSCs). Relevant information has been extracted from these inspection reports sorted into several categories; including Specific Aging Insights, Preventive Maintenance, Predictive Maintenance and Condition Monitoring, Post Maintenance Testing, Failure Trending, Root Cause Analysis and Usage of Probabilistic Risk Assessment in the Maintenance Process. Specific examples of inspection and monitoring techniques successfully used by utilities to detect degradation due to aging have been identified.

  16. Operation and Maintenance Manual for the Central Facilities Area Sewage Treatment Plant

    SciTech Connect

    Norm Stanley

    2011-02-01

    This Operation and Maintenance Manual lists operator and management responsibilities, permit standards, general operating procedures, maintenance requirements and monitoring methods for the Sewage Treatment Plant at the Central Facilities Area at the Idaho National Laboratory. The manual is required by the Municipal Wastewater Reuse Permit (LA-000141-03) the sewage treatment plant.

  17. Managing aging in nuclear power plants: Insights from NRC's Maintenance Team Inspection reports

    SciTech Connect

    Fresco, A.; Subudhi, M.

    1992-01-01

    A plant's maintenance program is the principal vehicle through which age-related degradation is managed. From 1988 to 1991, the NRC evaluated the maintenance program of every nuclear power plant in the United States. Forty-four out of a total of sixty-seven of the reports issued on these in-depth team inspections have been reviewed for insights into the strengths and weaknesses of the programs as related to the need to understand and manage the effects of aging on nuclear plant structures, systems, and components (SSCs). Relevant information has been extracted from these inspection reports sorted into several categories; including Specific Aging Insights, Preventive Maintenance, Predictive Maintenance and Condition Monitoring, Post Maintenance Testing, Failure Trending, Root Cause Analysis and Usage of Probabilistic Risk Assessment in the Maintenance Process. Specific examples of inspection and monitoring techniques successfully used by utilities to detect degradation due to aging have been identified.

  18. An Axenic Plant Culture System for Optimal Growth in Long-Term Studies: Design and Maintenance

    NASA Technical Reports Server (NTRS)

    Henry, Amelia; Doucette, William; Norton, Jeanette; Jones, Scott; Chard, Julie; Bugbee, Bruce

    2006-01-01

    The symbiotic co-evolution of plants and microbes leads to difficulties in understanding which of the two components is responsible for a given environmental response. Plant-microbe studies greatly benefit from the ability to grow plants in axenic (sterile) culture. Several studies have used axenic plant culture systems, but experimental procedures are often poorly documented, the plant growth environment is not optimal, and axenic conditions are not rigorously verified. We developed a unique axenic system using inert components that promotes plant health and can be kept sterile for at least 70 d. Crested wheatgrass (Agropyron cristatum cv. DII) plants were grown in sand within flow-through glass columns that were positively pressured with filtered air. Plant health was optimized by regulating temperature, light level, CO2 concentration, humidity, and nutrients. The design incorporates several novel aspects, such as pretreatment of the sand with Fe, graduated sand layers to optimize the air-water balance of the root zone, and modification of a laminar flow hood to serve as a plant growth chamber. Adaptations of several sterile techniques were necessary for maintenance of axenic conditions. Axenic conditions were verified by plating and staining leachates as well as rhizoplane stain. This system was designed to study nutrient and water stress effects on root exudates, but is useful for assessing a broad range of plant-microbe-environment interactions. Based on total organic C analysis, 74% of exudates was recovered in the leachate, 6% was recovered in the bulk sand, and 17% was recovered in the rhizosphere sand. Carbon in the leachate after 70 d reached 255 micro-g/d. Fumaric, malic, malonic, oxalic, and succinic acids were measured as components of the root exudates.

  19. Evaluation of mental workload on digital maintenance systems in nuclear power plants

    SciTech Connect

    Hwang, S. L.; Huang, F. H.; Lin, J. C.; Liang, G. F.; Yenn, T. C.; Hsu, C. C.

    2006-07-01

    The purpose of this study is to evaluate operators' mental workload dealing with digital maintenance systems in Nuclear Power Plants. First of all, according to the factors affected the mental workload, a questionnaire was designed to evaluate the mental workload of maintenance operators at the second Nuclear Power (NPP) in Taiwan. Then, sixteen maintenance engineers of the Second NPP participated in the questionnaire survey. The results indicated that the mental workload was lower in digital systems than that in analog systems. Finally, a mental workload model based on Neural Network technique was developed to predict the workload of maintenance operators in digital maintenance systems. (authors)

  20. School Building Maintenance Procedures. School Plant Management Series.

    ERIC Educational Resources Information Center

    Finchum, R.N.

    One of a series dealing with school management, the publication identifies and describes the function of, and outlines maintenance procedures for many components of school buildings. The purpose of maintenance is to safeguard the public's investment, increase the functional life of the building, and provide the best possible environment for…

  1. Light microscopy of whole plant organs.

    PubMed

    Timmers, Antonius C J

    2016-08-01

    Plants are ideal organisms for light microscopical studies of cellular mechanisms controlling cell organisation and cell functioning. However, most plant organs are not transparent to light which prevents high resolution imaging deep within plant tissues. Classically, access into plant organs is achieved by sectioning or whole-mount tissue clearing. Until recently, the protocols for clearing destroyed the signal from fluorescent markers which prevented the imaging of the distribution of fluorescent proteins and the three-dimensional reconstruction from optical slices of whole plant organs. From 2011, a number of protocols have been developed for whole brain and whole organism imaging for animal studies. Now, these protocols have been adapted for in-depth imaging of whole plant organs. Here, I present an overview of clearing techniques of plant organs and highlight the latest developments of plant tissue clearing in combination with high resolution fluorescence microscopy. PMID:27027806

  2. Managing aging in nuclear power plants: Insights from NRC maintenance team inspection reports

    SciTech Connect

    Fresco, A.; Subudhi, M.; Gunther, W.; Grove, E.; Taylor, J.

    1993-12-01

    A plant`s maintenance program is the principal vehicle through which age-related degradation is managed. From 1988 to 1991, the NRC evaluated the maintenance program of every nuclear power plant in the United States. Forty-four out of a total of 67 of the reports issued on these in-depth team inspections were reviewed for insights into the strengths and weaknesses of the programs as related to the need to understand and manage the effects of aging on nuclear plant systems, structures, and components. Relevant information was extracted from these inspection reports and sorted into several categories, including Specific Aging Insights, Preventive Maintenance, Predictive Maintenance and Condition Monitoring, Post Maintenance Testing, Failure Trending, Root Cause Analysis and Usage of Probabilistic Risk Assessment in the Maintenance Process. Specific examples of inspection and monitoring techniques successfully used by utilities to detect degradation due to aging have been identified. The information also was sorted according to systems and components, including: Auxiliary Feedwater, Main Feedwater, High Pressure Injection for both BWRs and PWRs, Service Water, Instrument Air, and Emergency Diesel Generator Air Start Systems, and Emergency Diesel Generators Air Start Systems, emergency diesel generators, electrical components such as switchgear, breakers, relays, and motor control centers, motor operated valves and check valves. This information was compared to insights gained from the Nuclear Plant Aging Research (NPAR) Program. Attributes of plant maintenance programs where the NRC inspectors felt that improvement was needed to properly address the aging issue also are discussed.

  3. Social Health Maintenance Organizations: assessing their initial experience.

    PubMed Central

    Newcomer, R; Harrington, C; Friedlob, A

    1990-01-01

    The Social/Health Maintenance Organization (S/HMO) is a four-site national demonstration. This program combines Medicare Part A and B coverage, with various extended and chronic care benefits, into an integrated health plan. The provision of these services extends both the traditional roles of HMOs and that of long-term care community-service case management systems. During the initial 30 months of operation the four S/HMOs shared financial risk with the Health Care Financing Administration. This article reports on this developmental period. During this phase the S/HMOs had lower-than-expected enrollment levels due in part to market competition, underfunding of marketing efforts, the limited geographic area served, and an inability to differentiate the S/HMO product from that of other Medicare HMOs. The S/HMOs were allowed to conduct health screening of applicants prior to enrolling them. The number of nursing home-certifiable enrollees was controlled through this mechanism, but waiting lists were never very long. Persons joining S/HMOs and other Medicare HMOs during this period were generally aware of the alternatives available. S/HMO enrollees favored the more extensive benefits; HMO enrollees considerations of cost. The S/HMOs compare both newly formed HMOs and established HMOs. On the basis of administrator cost, it is more efficient to add chronic care benefits to an HMO than to add an HMO component to a community care provider. All plans had expenses greater than their revenues during the start-up period, but they were generally able to keep service expenditures within planned levels. PMID:2116384

  4. Advanced Imaging Among Health Maintenance Organization Enrollees With Cancer

    PubMed Central

    Loggers, Elizabeth T.; Fishman, Paul A.; Peterson, Do; O'Keeffe-Rosetti, Maureen; Greenberg, Caprice; Hornbrook, Mark C.; Kushi, Lawrence H.; Lowry, Sarah; Ramaprasan, Arvind; Wagner, Edward H.; Weeks, Jane C.; Ritzwoller, Debra P.

    2014-01-01

    Purpose: Fee-for-service (FFS) Medicare expenditures for advanced imaging studies (defined as computed tomography [CT], magnetic resonance imaging [MRI], positron emission tomography [PET] scans, and nuclear medicine studies [NM]) rapidly increased in the past two decades for patients with cancer. Imaging rates are unknown for patients with cancer, whether under or over age 65 years, in health maintenance organizations (HMOs), where incentives may differ. Materials and Methods: Incident cases of breast, colorectal, lung, prostate, leukemia, and non-Hodgkin lymphoma (NHL) cancers diagnosed in 2003 and 2006 from four HMOs in the Cancer Research Network were used to determine 2-year overall mean imaging counts and average total imaging costs per HMO enrollee by cancer type for those under and over age 65. Results: There were 44,446 incident cancer patient cases, with a median age of 75 (interquartile range, 71-81), and 454,029 imaging procedures were performed. The mean number of images per patient increased from 7.4 in 2003 to 12.9 in 2006. Rates of imaging were similar across age groups, with the exception of greater use of echocardiograms and NM studies in younger patients with breast cancer and greater use of PET among younger patients with lung cancer. Advanced imaging accounted for approximately 41% of all imaging, or approximately 85% of the $8.7 million in imaging expenditures. Costs were nearly $2,000 per HMO enrollee; costs for younger patients with NHL, leukemia, and lung cancer were nearly $1,000 more in 2003. Conclusion: Rates of advanced imaging appear comparable among FFS and HMO participants of any age with these six cancers. PMID:24844241

  5. Operating and maintenance experiences at the Shamokin clum-burning boiler plant

    SciTech Connect

    Richards, H.W.; Laukaitis, J.F.; Fisher, B.L.; Gmeindl, F.D.; Lockman, H.

    1983-01-01

    A general overview of operating and maintenance experience at the Shamokin plant illustrates the feasibility of using anthracite refuse (culm) and fluidized-bed technology. Successful burning of the low-grade fuel took place over a range of operating conditions. The article describes a series of performance tests and the major maintenance items. 2 references, 7 figures.

  6. School Building Maintenance Procedures. School Plant Management Series. Bulletin, 1964, No. 17. OE-21027

    ERIC Educational Resources Information Center

    Finchum, R. N.

    1964-01-01

    Adequate maintenance of school buildings representing a public investment of billions of dollars is a problem of grave concern to both taxpayers and school officials. This publication, one of a series dealing with school plant management problems, identifies, describes, shows the function of, and outlines maintenance procedures for many components…

  7. 10 CFR 50.65 - Requirements for monitoring the effectiveness of maintenance at nuclear power plants.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... maintenance at nuclear power plants. 50.65 Section 50.65 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... Construction Permits § 50.65 Requirements for monitoring the effectiveness of maintenance at nuclear power..., including normal shutdown operations. (a)(1) Each holder of an operating license for a nuclear power...

  8. 10 CFR 50.65 - Requirements for monitoring the effectiveness of maintenance at nuclear power plants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... maintenance at nuclear power plants. 50.65 Section 50.65 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... Construction Permits § 50.65 Requirements for monitoring the effectiveness of maintenance at nuclear power..., including normal shutdown operations. (a)(1) Each holder of an operating license for a nuclear power...

  9. 10 CFR 50.65 - Requirements for monitoring the effectiveness of maintenance at nuclear power plants.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... maintenance at nuclear power plants. 50.65 Section 50.65 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... Construction Permits § 50.65 Requirements for monitoring the effectiveness of maintenance at nuclear power..., including normal shutdown operations. (a)(1) Each holder of an operating license for a nuclear power...

  10. 10 CFR 50.65 - Requirements for monitoring the effectiveness of maintenance at nuclear power plants.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... maintenance at nuclear power plants. 50.65 Section 50.65 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... Construction Permits § 50.65 Requirements for monitoring the effectiveness of maintenance at nuclear power..., including normal shutdown operations. (a)(1) Each holder of an operating license for a nuclear power...

  11. Wastewater Plant Operation and Maintenance--A Matter of Growing Concern

    ERIC Educational Resources Information Center

    Water and Wastes Engineering, 1978

    1978-01-01

    Responses of two experts to questions concerning wastewater plant operation and maintenance are presented. The responses discuss the scarcity of good personnel, training education available, and examples of existing improvement projects. (MA)

  12. Practical Maintenance of Digital Systems: Guidance to Maximize the Benefits of Digital Technology for the Maintenance of Digital Systems and Plant Equipment

    SciTech Connect

    Hill, D; Scarola, K

    2004-10-30

    This report presents detailed guidance for the maintenance and testing of modern digital systems. The guidance provides practical means for plants to take advantage of the increased diagnostic and self-test capabilities of these systems. It helps plants avoid mistakes in design and installation that could lead to increased maintenance burden and decreased system reliability and availability.

  13. Development and Implementation of a Condition Based Maintenance Program for Geothermal Power Plants

    SciTech Connect

    Steve Miller; Jim Eddy; Murray Grande; Shawn Bratt; Manuchehr Shirmohamadi

    2002-01-30

    This report describes the development of the RCM team, identifying plant assets and developing an asset hierarchy, the development of sample Failure Mode Effects Analysis (FMEAs), identifying and prioritizing plant systems and components for RCM analysis, and identifying RCM/CBM software/hardware vendors. It also includes the Failure Mode Effects Analysis (FMEA) for all Class I Systems, Maintenance Task Assignments, use of Conditioned Based Maintenance (CBM) Tools and Displays of the RCM software System Development to date.

  14. Antidepressant pharmacotherapy: economic outcomes in a health maintenance organization.

    PubMed

    Sclar, D A; Robison, L M; Skaer, T L; Legg, R F; Nemec, N L; Galin, R S; Hughes, T E; Buesching, D P

    1994-01-01

    Recent pharmacotherapeutic advances in the treatment of depression have included the development of selective serotonin re-uptake inhibitors (SSRIs). The present study was designed to contrast direct health service expenditures for the treatment of depression among patients enrolled in a health maintenance organization (HMO) and prescribed either the SSRI fluoxetine or one of three tricyclic antidepressants (TCAs) (amitriptyline, nortriptyline, or desipramine). Information regarding health service utilization was derived from the computer archive of a network-model HMO system serving 400,000 beneficiaries. A total of 701 HMO beneficiaries were found to satisfy the study selection criteria. Multivariate regression analysis was used to discern the incremental influence of selected demographic, clinical, financial, and provider characteristics on 1 year post-period expenditures (PPE) for health care. Analysis-of-variance procedures with Duncan's multiple-range test, or chi-square analyses, revealed no significant difference across antidepressant pharmacotherapy for age, sex, 6-month prior-period expenditures for physician visits, psychiatric visits, laboratory tests, hospitalizations, or psychiatric hospital services related to the treatment of depression, or number of prescribed therapeutic agents for disease state processes other than depression. Receipt of fluoxetine was associated with a significantly (P < or = 0.05) higher rate of initial prescribing by psychiatrists, an increase in the number of prescriptions for antidepressant pharmacotherapy obtained (30-day supplies), and a reduction in the number of monthly intervals during which time antidepressant pharmacotherapy was not procured. Receipt of fluoxetine as antidepressant pharmacotherapy was associated with a significantly (P < or = 0.05) higher mean medication possession ratio (MPR) relative to amitriptyline, nortriptyline, or desipramine. Multivariate findings for patient-level data reflecting a definitive

  15. Maintenance of xylem network transport capacity: a review of embolism repair in vascular plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maintenance of long distance water transport in xylem is essential to plant health and productivity. Both biotic and abiotic environmental conditions lead to embolism formation within the xylem resulting in lost transport capacity and ultimately death following systemic spread. Plants exhibit a vari...

  16. Monitoring well inspection and maintenance plan Y-12 Plant, Oak Ridge, Tennessee (revised)

    SciTech Connect

    1996-09-01

    Inspection and maintenance of groundwater monitoring wells is a primary element of the Oak Ridge Y-12 Plant Groundwater Protection Program (GWPP). This document is the revised groundwater monitoring well inspection and maintenance plan for the U.S. Department of Energy (DOE) Y-12 Plant in Oak Ridge, Tennessee. The plan provides a systematic program for: (1) inspecting the physical condition of monitoring wells at the Y-12 Plant and (2) identifying maintenance needs that will extend the life of each well and ensure that representative groundwater quality samples and hydrologic data are collected from the wells. Original documentation for the Y-12 Plant GWPP monitoring well inspection and maintenance program was provided in HSW, Inc. 1991a. The original revision of the plan specified that only a Monitoring Well Inspection/Maintenance Summary need be updated and reissued each year. Rapid growth of the monitoring well network and changing regulatory requirements have resulted in constant changes to the status of wells (active or inactive) listed on the Monitoring Well Inspection/Maintenance Summary. As a result, a new mechanism to track the status of monitoring wells has been developed and the plan revised to formalize the new business practices. These changes are detailed in Sections 2.4 and 2.5.

  17. Health maintenance organizations; Midwest Health Plan--Health Resources and Services Administration.

    PubMed

    1983-04-26

    On January 21, 1983, the Office of Health Maintenance Organizations (OHMO) notified Midwest Health Plan (MHP), 3415 Bridgeland Drive, Bridgeton, Missouri 63044, a federally qualified health maintenance organization (HMO), that MHP had successfully reestablished compliance with its assurances to the Secretary that it would (1) maintain a fiscally sound operation, and (2) maintain satisfactory administrative and managerial arrangements. This determination took effect on January 1, 1983. PMID:10324428

  18. Results of calendar year 1995 Well Inspection and Maintenance Program Y-12 Plant, Oak Ridge, Tennessee

    SciTech Connect

    McMaster, B.W.

    1996-07-01

    This document is a compendium of results of the 1995 Monitor Well Inspection and Maintenance Program at the US Department of Energy`s Oak Ridge Y-12 Plant. This report documents the work relating to well inspections and maintenance requests. Inspections are implemented in order to better assess the condition and maintenance needs of wells that are actively being monitored. Currently this approach calls for inspecting all wells on a routine (annual or triennial) basis which are: (1) in an active sampling program; (2) included in a hydrologic study; or (3) not in service, but not scheduled for plugging and abandonment. Routine inspections help to ensure that representative groundwater samples and hydrologic data are being collected, and contribute to the effective longevity of each well. This report formally presents well inspection and maintenance activities that were conducted at the Y-12 Plant from August through December 1995.

  19. Recombination and the maintenance of plant organelle genome stability.

    PubMed

    Maréchal, Alexandre; Brisson, Normand

    2010-04-01

    Like their nuclear counterpart, the plastid and mitochondrial genomes of plants have to be faithfully replicated and repaired to ensure the normal functioning of the plant. Inability to maintain organelle genome stability results in plastid and/or mitochondrial defects, which can lead to potentially detrimental phenotypes. Fortunately, plant organelles have developed multiple strategies to maintain the integrity of their genetic material. Of particular importance among these processes is the extensive use of DNA recombination. In fact, recombination has been implicated in both the replication and the repair of organelle genomes. Revealingly, deregulation of recombination in organelles results in genomic instability, often accompanied by adverse consequences for plant fitness. The recent identification of four families of proteins that prevent aberrant recombination of organelle DNA sheds much needed mechanistic light on this important process. What comes out of these investigations is a partial portrait of the recombination surveillance machinery in which plants have co-opted some proteins of prokaryotic origin but have also evolved whole new factors to keep their organelle genomes intact. These new features presumably optimized the protection of plastid and mitochondrial genomes against the particular genotoxic stresses they face. PMID:20180912

  20. Formation And Maintenance of Self-Organizing Wireless Networks

    NASA Technical Reports Server (NTRS)

    Scott, Keith; Bambos, Nicholas

    1997-01-01

    There are numerous military, commercial, and scientific applications for mobile wireless networks which are able to self-Organize without recousre to any pre-existing infrastructure. We present the Self Organizing Wireless Adaptive Network protocol, a distributed networking protocol capable of managing such networks.

  1. Security Design of Remote Maintenance Systems for Nuclear Power Plants Based on ISO/IEC 15408

    NASA Astrophysics Data System (ADS)

    Watabe, Ryosuke; Oi, Tadashi; Endo, Yoshio

    This paper presents a security design of remote maintenance systems for nuclear power plants. Based on ISO/IEC 15408, we list assets to be protected, threats to the assets, security objectives against the threats, and security functional requirements that achieve the security objectives. Also, we show relations between the threats and the security objectives, and relations between the security objectives and the security functional requirements. As a result, we concretize a necessary and sufficient security design of remote maintenance systems for nuclear power plants that can protect the instrumentation and control system against intrusion, impersonation, tapping, obstruction and destruction.

  2. Organic control of plant diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic agriculture refers to agricultural production systems that are managed according to a number of standards which vary by governing body or political entity, but which share a common philosophy and set of general management practices. In popular culture, organic crop production is generally un...

  3. Effects of Message Interactivity upon Relational Maintenance Strategy in Digital Communications between Organizations and the Public

    ERIC Educational Resources Information Center

    Liu, Zhan-Qing

    2012-01-01

    Digital communication between organizations and the public is strategically important in shaping mutual understanding and long term relationship. The primary focus of this project was to investigate the relationship between message interactivity and relational maintenance strategy in the email communication process on organization websites. At…

  4. Nuclear power plant maintenance personnel reliability prediction (NPP/MPRP) effort at Oak Ridge National Laboratory

    SciTech Connect

    Knee, H.E.; Haas, P.M.; Siegel, A.I.

    1981-01-01

    Human errors committed during maintenance activities are potentially a major contribution to the overall risk associated with the operation of a nuclear power plant (NPP). An NRC-sponsored program at Oak Ridge National Laboratory is attempting to develop a quantitative predictive technique to evaluate the contribution of maintenance errors to the overall NPP risk. The current work includes a survey of the requirements of potential users to ascertain the need for and content of the proposed quantitative model, plus an initial job/task analysis to determine the scope and applicability of various maintenance tasks. In addition, existing human reliability prediction models are being reviewed and assessed with respect to their applicability to NPP maintenance tasks. This paper discusses the status of the program and summarizes the results to date.

  5. Organization and Maintenance of Data in Employment Discrimination Litigation

    ERIC Educational Resources Information Center

    Christenson, Bruce A.; Maher, Kathleen M.; Mueller, Lorin M.

    2008-01-01

    Modern organizations such as institutions of higher education characteristically include various administrative offices that gather and maintain records on employees and applicants for employment as part of their normal course of business. The objective of such record keeping is generally that of promoting efficient and effective management of an…

  6. Experience report on coating concrete containment structures in a maintenance environment in power plants

    SciTech Connect

    Poncio, S.; Hall, D.

    1997-12-01

    Work experiences for coatings and lining applications in power plants are used to provide guidelines and recommendations for future projects. It should be emphasized that some of the work experiences are applicable to other industries, but the scope of this paper is primarily for maintenance concrete coating for immersion service in power plants. Also the importance of preplanning and scheduling of the concrete coating project is discussed.

  7. STEAM PLANT, TRA609. FIRST FLOOR PLAN. STEAM UNITS, OFFICE, MAINTENANCE ...

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

    STEAM PLANT, TRA-609. FIRST FLOOR PLAN. STEAM UNITS, OFFICE, MAINTENANCE AREA, UTILITY ROOM FOR ELECTRIC GEAR, AIR INTAKE AND FILTERING, DIESEL GENERATOR. BLAW-KNOX 3150-809-2, 8/1950. INL INDEX NO. 531-0609-00-098-100684, REV. 3. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  8. 77 FR 30030 - Monitoring the Effectiveness of Maintenance at Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ...-1278, was published in the Federal Register on September 6, 2011 (76 FR 55137) for a 60 day public comment period. The public comment period was extended from October 31, 2011 to November 11, 2011 (76 FR... Effectiveness of Maintenance at Nuclear Power Plants,'' Part 50, ``Domestic Licensing of Production...

  9. Reduction of operations and maintenance costs at geothermal power plants

    SciTech Connect

    Bruton, C.J.; Stevens, C.G.; Rard, J.A.; Kasameyer, P.W.

    1997-12-31

    To reduce chemical costs at geothermal power plants, we are investigating: (a) improved chemical processes associated with H{sub 2}S abatement techniques, and (b) the use of cross dispersive infrared spectrometry to monitor accurately, reliably, and continuously H{sub 2}S emissions from cooling towers. The latter is a new type of infrared optical technology developed by LLNL for non-proliferation verification. Initial work is focused at The Geysers in cooperation with Pacific Gas and Electric. Methods for deploying the spectrometer on-site at The Geysers are being developed. Chemical analysis of solutions involved in H{sub 2}S abatement technologies is continuing to isolate the chemical forms of sulfur produced.

  10. Compact probing system using remote imaging for industrial plant maintenance

    NASA Astrophysics Data System (ADS)

    Ito, F.; Nishimura, A.

    2014-03-01

    Laser induced breakdown spectroscopy (LIBS) and endoscope observation were combined to design a remote probing device. We use this probing device to inspect a crack of the inner wall of the heat exchanger. Crack inspection requires speed at first, and then it requires accuracy. Once Eddy Current Testing (ECT) finds a crack with a certain signal level, another method should confirm it visually. We are proposing Magnetic particle Testing (MT) using specially fabricated the Magnetic Particle Micro Capsule (MPMC). For LIBS, a multichannel spectrometer and a Q-switch YAG laser were used. Irradiation area is 270 μm, and the pulse energy was 2 mJ. This pulse energy corresponds to 5-2.2 MW/cm2. A composite-type optical fiber was used to deliver both laser energy and optical image. Samples were prepared to heat a zirconium alloy plate by underwater arc welding in order to demonstrate severe accidents of nuclear power plants. A black oxide layer covered the weld surface and white particles floated on water surface. Laser induced breakdown plasma emission was taken into the spectroscope using this optical fiber combined with telescopic optics. As a result, we were able to simultaneously perform spectroscopic measurement and observation. For MT, the MPMC which gathered in the defective area is observed with this fiber. The MPMC emits light by the illumination of UV light from this optical fiber. The size of a defect is estimated with this amount of emission. Such technology will be useful for inspection repair of reactor pipe.

  11. 26 CFR 1.528-2 - Organized and operated to provide for the acquisition, construction, management, maintenance and...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... acquisition, construction, management, maintenance and care of association property. 1.528-2 Section 1.528-2... acquisition, construction, management, maintenance and care of association property. (a) Organized and... association are the acquisition, construction, management, maintenance, and care of association property....

  12. 26 CFR 1.528-2 - Organized and operated to provide for the acquisition, construction, management, maintenance and...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... acquisition, construction, management, maintenance and care of association property. 1.528-2 Section 1.528-2... acquisition, construction, management, maintenance and care of association property. (a) Organized and... association are the acquisition, construction, management, maintenance, and care of association property....

  13. 26 CFR 1.528-2 - Organized and operated to provide for the acquisition, construction, management, maintenance and...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... acquisition, construction, management, maintenance and care of association property. 1.528-2 Section 1.528-2... acquisition, construction, management, maintenance and care of association property. (a) Organized and... association are the acquisition, construction, management, maintenance, and care of association property....

  14. 26 CFR 1.528-2 - Organized and operated to provide for the acquisition, construction, management, maintenance and...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... acquisition, construction, management, maintenance and care of association property. 1.528-2 Section 1.528-2... acquisition, construction, management, maintenance and care of association property. (a) Organized and... association are the acquisition, construction, management, maintenance, and care of association property....

  15. 26 CFR 1.528-2 - Organized and operated to provide for the acquisition, construction, management, maintenance and...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... acquisition, construction, management, maintenance and care of association property. 1.528-2 Section 1.528-2... acquisition, construction, management, maintenance and care of association property. (a) Organized and... association are the acquisition, construction, management, maintenance, and care of association property....

  16. Precursor Report of Data Needs and Recommended Practices for PV Plant Availability Operations and Maintenance Reporting.

    SciTech Connect

    Hill, Roger R.; Klise, Geoffrey Taylor; Balfour, John R.

    2015-01-01

    Characterizing the factors that affect reliability of a photovoltaic (PV) power plant is an important aspect of optimal asset management. This document describes the many factors that affect operation and maintenance (O&M) of a PV plant, identifies the data necessary to quantify those factors, and describes how data might be used by O&M service providers and others in the PV industry. This document lays out data needs from perspectives of reliability, availability, and key performance indicators and is intended to be a precursor for standardizing terminology and data reporting, which will improve data sharing, analysis, and ultimately PV plant performance.

  17. A DNA2 Homolog Is Required for DNA Damage Repair, Cell Cycle Regulation, and Meristem Maintenance in Plants1[OPEN

    PubMed Central

    Jia, Ning; Liu, Xiaomin; Gao, Hongbo

    2016-01-01

    Plant meristem cells divide and differentiate in a spatially and temporally regulated manner, ultimately giving rise to organs. In this study, we isolated the Arabidopsis jing he sheng 1 (jhs1) mutant, which exhibited retarded growth, an abnormal pattern of meristem cell division and differentiation, and morphological defects such as fasciation, an irregular arrangement of siliques, and short roots. We identified JHS1 as a homolog of human and yeast DNA Replication Helicase/Nuclease2, which is known to be involved in DNA replication and damage repair. JHS1 is strongly expressed in the meristem of Arabidopsis. The jhs1 mutant was sensitive to DNA damage stress and had an increased DNA damage response, including increased expression of genes involved in DNA damage repair and cell cycle regulation, and a higher frequency of homologous recombination. In the meristem of the mutant plants, cell cycle progression was delayed at the G2 or late S phase and genes essential for meristem maintenance were misregulated. These results suggest that JHS1 plays an important role in DNA replication and damage repair, meristem maintenance, and development in plants. PMID:26951435

  18. Who is Using Telehealth in Primary Care? Safety Net Clinics and Health Maintenance Organizations (HMOs).

    PubMed

    Coffman, Megan; Moore, Miranda; Jetty, Anuradha; Klink, Kathleen; Bazemore, Andrew

    2016-01-01

    Despite rapid advancements in telehealth services, only 15% of family physicians in a 2014 survey reported using telehealth; use varied widely according to the physician's practice setting or designation. Users were significantly more likely than nonusers to work in federally designated "safety net" clinics and health maintenance organizations (HMOs) but not more likely than nonusers to report working in a patient-centered medical home (PCMH) or accountable care organization. PMID:27390373

  19. Maintenance of genome stability in plants: repairing DNA double strand breaks and chromatin structure stability.

    PubMed

    Roy, Sujit

    2014-01-01

    Plant cells are subject to high levels of DNA damage resulting from plant's obligatory dependence on sunlight and the associated exposure to environmental stresses like solar UV radiation, high soil salinity, drought, chilling injury, and other air and soil pollutants including heavy metals and metabolic by-products from endogenous processes. The irreversible DNA damages, generated by the environmental and genotoxic stresses affect plant growth and development, reproduction, and crop productivity. Thus, for maintaining genome stability, plants have developed an extensive array of mechanisms for the detection and repair of DNA damages. This review will focus recent advances in our understanding of mechanisms regulating plant genome stability in the context of repairing of double stand breaks and chromatin structure maintenance. PMID:25295048

  20. Cell-phone based assistance for waterworks/sewage plant maintenance.

    PubMed

    Kawada, T; Nakamichi, K; Hisano, N; Kitamura, M; Miyahara, K

    2006-01-01

    Cell-phones are now incorporating the functions necessary for them to be used as mobile IT devices. In this paper, we present our results of the evaluation of cell-phones as the mobile IT device to assist workers in industrial plants. We use waterworks and sewage plants as examples. By employing techniques to squeeze the SCADA screen on CRT into a small cell-phone LCD, we have made it easier for a plant's field workers to access the information needed for effective maintenance, regardless of location. An idea to link SCADA information and the plant facility information on the cell-phone is also presented. Should an accident or emergency situation arise, these cell-phone-based IT systems can efficiently deliver the latest plant information, thus the worker out in the field can respond to and resolve the emergency. PMID:16722075

  1. An intelligent systems approach for on-line power plant efficiency, emisions, and maintenance diagnostics

    SciTech Connect

    Hunt, M.; Williams, S.; Hickok, K.

    1995-06-01

    The Fossil Thermal performance Advisor{sup TM} (FTPA{sup TM}), developed by New York State Electric & Gas Corporation (NYSEG) and personnel from DHR Technologies, Inc. (DHR), is an advanced, on-line Electronic Performance Support System (EPSS) that helps fossil power plant operators, performance engineers, and plant managers improve daily plant operations. The FTPA uses an intelligent systems approach to identify existing and potential heat rate, emissions, and maintenance-related problems early, and to provide recommendations to help plant staff reduce costs related to these problems. The FTPA has been installed in several plants throughout the United States and abroad, most recently at NYSEG`s Greenridge Station, Unit No. 4. Currently, another system is being installed at Portland General Electric`s Boardman Station. This paper examines advances in the FTPA architecture designed to significantly reduce installation costs while increasing the benefits provided by the FTPA for smaller pulverized coal units, such as Greenidge Unit No. 4.

  2. CERN experience and strategy for the maintenance of cryogenic plants and distribution systems

    NASA Astrophysics Data System (ADS)

    Serio, L.; Bremer, J.; Claudet, S.; Delikaris, D.; Ferlin, G.; Pezzetti, M.; Pirotte, O.; Tavian, L.; Wagner, U.

    2015-12-01

    CERN operates and maintains the world largest cryogenic infrastructure ranging from ageing installations feeding detectors, test facilities and general services, to the state-of-the-art cryogenic system serving the flagship LHC machine complex. After several years of exploitation of a wide range of cryogenic installations and in particular following the last two years major shutdown to maintain and consolidate the LHC machine, we have analysed and reviewed the maintenance activities to implement an efficient and reliable exploitation of the installations. We report the results, statistics and lessons learned on the maintenance activities performed and in particular the required consolidations and major overhauling, the organization, management and methodologies implemented.

  3. Plant disease management in organic farming systems.

    PubMed

    van Bruggen, Ariena H C; Gamliel, Abraham; Finckh, Maria R

    2016-01-01

    Organic farming (OF) has significantly increased in importance in recent decades. Disease management in OF is largely based on the maintenance of biological diversity and soil health by balanced crop rotations, including nitrogen-fixing and cover crops, intercrops, additions of manure and compost and reductions in soil tillage. Most soil-borne diseases are naturally suppressed, while foliar diseases can sometimes be problematic. Only when a severe disease outbreak is expected are pesticides used that are approved for OF. A detailed overview is given of cultural and biological control measures. Attention is also given to regulated pesticides. We conclude that a systems approach to disease management is required, and that interdisciplinary research is needed to solve lingering disease problems, especially for OF in the tropics. Some of the organic regulations are in need of revision in close collaboration with various stakeholders. PMID:26331771

  4. Parabolic Trough Organic Rankine Cycle Power Plant

    SciTech Connect

    Canada, S.; Cohen, G.; Cable, R.; Brosseau, D.; Price, H.

    2005-01-01

    Arizona Public Service (APS) is required to generate a portion of its electricity from solar resources in order to satisfy its obligation under the Arizona Environmental Portfolio Standard (EPS). In recent years, APS has installed and operates over 4.5 MWe of fixed, tracking, and concentrating photovoltaic systems to help meet the solar portion of this obligation and to develop an understanding of which solar technologies provide the best cost and performance to meet utility needs. During FY04, APS began construction of a 1-MWe parabolic trough concentrating solar power plant. This plant represents the first parabolic trough plant to begin construction since 1991. The plant will also be the first commercial deployment of the Solargenix parabolic trough collector technology developed under contract to the National Renewable Energy Laboratory (NREL). The plant will use an organic Rankine cycle (ORC) power plant, provided by Ormat. The ORC power plant is much simpler than a conventional steam Rankine cycle power plant and allows unattended operation of the facility.

  5. Distinct target-derived signals organize formation, maturation, and maintenance of motor nerve terminals.

    PubMed

    Fox, Michael A; Sanes, Joshua R; Borza, Dorin-Bogdan; Eswarakumar, Veraragavan P; Fässler, Reinhard; Hudson, Billy G; John, Simon W M; Ninomiya, Yoshifumi; Pedchenko, Vadim; Pfaff, Samuel L; Rheault, Michelle N; Sado, Yoshikazu; Segal, Yoav; Werle, Michael J; Umemori, Hisashi

    2007-04-01

    Target-derived factors organize synaptogenesis by promoting differentiation of nerve terminals at synaptic sites. Several candidate organizing molecules have been identified based on their bioactivities in vitro, but little is known about their roles in vivo. Here, we show that three sets of organizers act sequentially to pattern motor nerve terminals: FGFs, beta2 laminins, and collagen alpha(IV) chains. FGFs of the 7/10/22 subfamily and broadly distributed collagen IV chains (alpha1/2) promote clustering of synaptic vesicles as nerve terminals form. beta2 laminins concentrated at synaptic sites are dispensable for embryonic development of nerve terminals but are required for their postnatal maturation. Synapse-specific collagen IV chains (alpha3-6) accumulate only after synapses are mature and are required for synaptic maintenance. Thus, multiple target-derived signals permit discrete control of the formation, maturation, and maintenance of presynaptic specializations. PMID:17418794

  6. The health maintenance organization strategy: a corporate takeover of health services delivery.

    PubMed

    Salmon, J W

    1975-01-01

    This paper presents a political economic framework for viewing the social organization of the delivery of health care servies and predicting a qualitatively different institutional configuration involving the health maintenance organization. The principal forces impacting American capitalism today are leading to a fundamental restructuring for increased social efficiency of the entire social welfare sector, including the health services industry. The method to achieve this restructuring involves health policy directed at raising the contribution to the social surplus from the delivery of health care services and eventual corporate domination. The health maintenance organization conceptualization is examined with suggestions as to how the HMO strategy promoted by the state leads to this corporate takeover. The mechanism and extent of the present corporate involvement are examined and implications of health services as a social control mechanism are presented. PMID:1230440

  7. Wet deposition of mercury within the vicinity of a cement plant before and during cement plant maintenance

    NASA Astrophysics Data System (ADS)

    Rothenberg, Sarah E.; McKee, Lester; Gilbreath, Alicia; Yee, Donald; Connor, Mike; Fu, Xuewu

    2010-03-01

    Hg species (total mercury, methylmercury, reactive mercury) in precipitation were investigated in the vicinity of the Lehigh Hanson Permanente Cement Plant in the San Francisco Bay Area, CA., USA. Precipitation was collected weekly between November 29, 2007 and March 20, 2008, which included the period in February and March 2008 when cement production was minimized during annual plant maintenance. When the cement plant was operational, the volume weighted mean (VWM) and wet depositional flux for total Hg (Hg T) were 6.7 and 5.8 times higher, respectively, compared to a control site located 3.5 km east of the cement plant. In February and March, when cement plant operations were minimized, levels were approximately equal at both sites (the ratio for both parameters was 1.1). Due to the close proximity between the two sites, meteorological conditions (e.g., precipitation levels, wind direction) were similar, and therefore higher VWM Hg T levels and Hg T deposition likely reflected increased Hg emissions from the cement plant. Methylmercury (MeHg) and reactive Hg (Hg(II)) were also measured; compared to the control site, the VWM for MeHg was lower at the cement plant (the ratio = 0.75) and the VWM for Hg(II) was slightly higher (ratio = 1.2), which indicated the cement plant was not likely a significant source of these Hg species to the watershed.

  8. 78 FR 15753 - Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-12

    ... COMMISSION Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power..., DG-1269 ``Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear... lead-acid storage batteries in nuclear power plants. DATES: Submit comments by May 13, 2013....

  9. The mechanics and energetics of soil bioturbation by earthworms and plant roots - Impacts on soil structure generation and maintenance

    NASA Astrophysics Data System (ADS)

    Or, Dani; Ruiz, Siul; Schymanski, Stanlislaus

    2015-04-01

    Soil structure is the delicate arrangement of solids and voids that facilitate numerous hydrological and ecological soil functions ranging from water infiltration and retention to gaseous exchange and mechanical anchoring of plant roots. Many anthropogenic activities affect soil structure, e.g. via tillage and compaction, and by promotion or suppression of biological activity and soil carbon pools. Soil biological activity is critical to the generation and maintenance of favorable soil structure, primarily through bioturbation by earthworms and root proliferation. The study aims to quantify the mechanisms, rates, and energetics associated with soil bioturbation, using a new biomechanical model to estimate stresses required to penetrate and expand a cylindrical cavity in a soil under different hydration and mechanical conditions. The stresses and soil displacement involved are placed in their ecological context (typical sizes, population densities, burrowing rates and behavior) enabling estimation of mechanical energy requirements and impacts on soil organic carbon pool (in the case of earthworms). We consider steady state plastic cavity expansion to determine burrowing pressures of earthworms and plant roots, akin to models of cone penetration representing initial burrowing into soil volumes. Results show that with increasing water content the strain energy decreases and suggest trade-offs between cavity expansion pressures and energy investment for different root and earthworm geometries and soil hydration. The study provides a quantitative framework for estimating energy costs of bioturbation in terms of soil organic carbon or the mechanical costs of soil exploration by plant roots as well as mechanical and hydration limits to such activities.

  10. Medicare health maintenance organizations. An industry analysis for the elderly in the USA.

    PubMed

    Asubonteng, P; Tucker, J; Munchus, G

    1996-01-01

    Provides a review and analysis of Medicare health maintenance organizations in the USA. The Porter model of industry structure is used. Discusses the issues of suppliers, buyers, market entry and substitutes. Indicates there is currently no intense rivalry among Medicare risk-based HMOs. However, the Porter model reveals crucial information regarding the forces which drive industry competition. Trends in the field of managed care and Medicare financing continue to be a real challenge regarding future research. PMID:10162927

  11. The Vaccine Safety Datalink: immunization research in health maintenance organizations in the USA.

    PubMed Central

    Chen, R. T.; DeStefano, F.; Davis, R. L.; Jackson, L. A.; Thompson, R. S.; Mullooly, J. P.; Black, S. B.; Shinefield, H. R.; Vadheim, C. M.; Ward, J. I.; Marcy, S. M.

    2000-01-01

    The Vaccine Safety Datalink is a collaborative project involving the National Immunization Program of the Centers for Disease Control and Prevention and several large health maintenance organizations in the USA. The project began in 1990 with the primary purpose of rigorously evaluating concerns about the safety of vaccines. Computerized data on vaccination, medical outcome (e.g. outpatient visits, emergency room visits, hospitalizations, and deaths) and covariates (e.g. birth certificates, census data) are prospectively collected and linked under joint protocol at multiple health maintenance organizations for analysis. Approximately 6 million persons (2% of the population of the USA) are now members of health maintenance organizations participating in the Vaccine Safety Datalink, which has proved to be a valuable resource providing important information on a number of vaccine safety issues. The databases and infrastructure created for the Vaccine Safety Datalink have also provided opportunities to address vaccination coverage, cost-effectiveness and other matters connected with immunization as well as matters outside this field. PMID:10743283

  12. Maintaining Change: The Maintenance Function and the Change Process.

    ERIC Educational Resources Information Center

    Cooke, Fang Lee

    2003-01-01

    Explores the organization of the maintenance function of five manufacturing and utility companies and the involvement of maintenance workers in plant improvement. Highlights the role of tacit skills of maintenance workers and of the maintenance function on technological change and organizational performance. (Contains 41 references.) (JOW)

  13. Industrial Maintenance Strategies

    SciTech Connect

    Sajjad Akbar

    2006-07-01

    Industrial plants have become more complex due to technological advancement. This has made the task of maintenance more difficult. The maintenance costs in terms of resources and downtime loss are so high that maintenance function has become a critical factor in a plant's profitability. Industry should devote as much forethought to the management of maintenance function as to production. Maintenance has grown from an art to a precise, technical engineering science. Planning, organizing scheduling and control of maintenance using modern techniques pays dividends in the form of reduced costs and increased reliability. The magnitude and the dimension of maintenance have multiplied due to development in the engineering technologies. Production cost and capacities are directly affected by the breakdown time. Total operating cost including the maintenance cost plays an important role in replacement dimension. The integrated system approach would bring forth the desired results of high maintenance standards. The standards once achieved and sustained, would add to the reliability of the plan and relieve heavy stresses and strains on the engineering logistic support. (author)

  14. Does proximity to physical activity infrastructures predict maintenance of organized and unorganized physical activities in youth?

    PubMed Central

    MacKenzie, Jason; Brunet, Jennifer; Boudreau, Jonathan; Iancu, Horia-Daniel; Bélanger, Mathieu

    2015-01-01

    Physical activity (PA) infrastructures can provide youth chances to engage in PA. As determinants of organized and unorganized PA (OPA and UPA) may differ, we investigated if proximity to PA infrastructures (proximity) was associated with maintenance of OPA and UPA over 3 years. Youth from New Brunswick, Canada (n = 187; 10–12 years at baseline) reported participation in OPA and UPA every 4 months from 2011 to 2014 as part of the MATCH study. Proximity data were drawn from parent's questionnaires. Proximity scores were divided into tertiles. Kaplan–Meier and Cox proportional hazard models were used to assess associations between proximity and maintenance of OPA and UPA. There were no crude or adjusted differences in average maintenance of participation in OPA [mean number of survey cycle participation (95%CI) was 6.6 (5.7–7.5), 6.3 (5.5–7.1), and 5.8 (5.1–6.6)] or UPA [6.8 (6.2–7.4), 5.9 (5.3–6.5), and 6.6 (5.9–7.3)] across low, moderate, and high tertiles of proximity, respectively. Findings suggest that proximity does not affect maintenance of participation in OPA or UPA during adolescence. Other environmental aspects may have a greater effect. Further research is needed before conclusions can be made. PMID:26844149

  15. The plant cell wall integrity maintenance mechanism--a case study of a cell wall plasma membrane signaling network.

    PubMed

    Hamann, Thorsten

    2015-04-01

    Some of the most important functions of plant cell walls are protection against biotic/abiotic stress and structural support during growth and development. A prerequisite for plant cell walls to perform these functions is the ability to perceive different types of stimuli in both qualitative and quantitative manners and initiate appropriate responses. The responses in turn involve adaptive changes in cellular and cell wall metabolism leading to modifications in the structures originally required for perception. While our knowledge about the underlying plant mechanisms is limited, results from Saccharomyces cerevisiae suggest the cell wall integrity maintenance mechanism represents an excellent example to illustrate how the molecular mechanisms responsible for stimulus perception, signal transduction and integration can function. Here I will review the available knowledge about the yeast cell wall integrity maintenance system for illustration purposes, summarize the limited knowledge available about the corresponding plant mechanism and discuss the relevance of the plant cell wall integrity maintenance mechanism in biotic stress responses. PMID:25446233

  16. Coping with coal quality impacts on power plant operation and maintenance

    SciTech Connect

    Hatt, R.

    1998-12-31

    The electric power industry is rapidly changing due to deregulation. The author was present one hot day in June of this year, when a southeastern utility company was selling electricity for $5,000.00 per megawatt with $85.00 cost. Typical power cost range from the mid teens at night to about $30.00 on a normal day. The free market place will challenge the power industry in many ways. Fuel is the major cost in electric power. In a regulated industry the cost of fuel was passed on to the customers. Fuels were chosen to minimize problems such as handling, combustion, ash deposits and other operational and maintenance concerns. Tight specifications were used to eliminate or minimize coals that caused problems. These tight specifications raised the price of fuel by minimizing competition. As the power stations become individual profit centers, plant management must take a more proactive role in fuel selection. Understanding how coal quality impacts plant performance and cost, allows better fuel selection decisions. How well plants take advantage of their knowledge may determine whether they will be able to compete in a free market place. The coal industry itself can provide many insights on how to survive in this type of market. Coal mines today must remain competitive or be shut down. The consolidation of the coal industry indicates the trends that can occur in a competitive market. These trends have already started, and will continue in the utility industry. This paper will discuss several common situations concerning coal quality and potential solutions for the plant to consider. All these examples have mill maintenance and performance issues in common. This is indicative of how important pulverizers are to the successful operation of a power plant.

  17. 29 CFR 458.31 - Maintenance of fiscal integrity in the conduct of the affairs of labor organizations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 2 2010-07-01 2010-07-01 false Maintenance of fiscal integrity in the conduct of the affairs of labor organizations. 458.31 Section 458.31 Labor Regulations Relating to Labor OFFICE OF LABOR... Concerning Standards of Conduct Additional Provisions Applicable § 458.31 Maintenance of fiscal integrity...

  18. Information system design of inventory control spare parts maintenance (valuation class 5000) (case study: plant kw)

    NASA Astrophysics Data System (ADS)

    Fitriana, Rina; Moengin, Parwadi; Riana, Mega

    2016-02-01

    Plat KW hadn't using optimal inventory level planning yet and hadn't have an information system that well computerized. The research objective is to be able to design an information system related inventory control of spare parts maintenance. The study focused on five types of spare parts with the highest application rate during February 2013- March 2015 and included in the classification of fast on FSN analysis Grinding stones Cut 4". Cable Tie 15". Welding RB 26-32MM. Ring Plat ½" and Ring Plate 5/8 ". Inventory calculation used Economic Order Quantity (EOQ). Safety Stock (SS) and Reorder Point (ROP) methods. System analysis conducted using the framework PIECES with the proposed inventory control system. the performance of the plant KW relating to the supply of spare parts maintenance needs can be more efficient as well as problems at the company can be answered and can perform inventory cost savings amounting Rp.267.066. A computerized information system of inventory control spare parts maintenance provides a menu that can be accessed by each departments as the user needed.

  19. School Facilities Maintenance and Operations Manual.

    ERIC Educational Resources Information Center

    Association of School Business Officials International, Reston, VA.

    Often a community's largest single investment is in its physical plants, including public school buildings and grounds. An essential factor in efficient school district operation is a well-organized, responsive plant operations and maintenance division. Maintenance has generally been defined as those services, activities, and procedures concerned…

  20. Mortality among maintenance employees potentially exposed to asbestos in a refinery and petrochemical plant.

    PubMed

    Tsai, S P; Waddell, L C; Gilstrap, E L; Ransdell, J D; Ross, C E

    1996-01-01

    This paper reports the mortality experience from 1948 to 1989 of 2,504 maintenance employees who had a minimum of one year of employment in jobs with potential exposure to asbestos at a Texas refinery and petrochemical plant. For the purposes of this study, "potential exposure" is equated with those jobs or crafts having the greatest direct potential proximity to, or which worked directly with, asbestos-containing materials, especially asbestos-containing thermal insulation. Approximately one-half of the study population had 10 years or longer potential exposure, and 80% had their first potential exposure before 1970. The total population exhibited significantly lower mortality for all causes, the standardized mortality ratio (SMR = 77); and for all cancer (SMR = 85), as compared to residents in the surrounding communities. Statistically significant deficits in mortality were also observed in a number of noncancerous diseases such as heart disease (SMR = 78; 95% CI = 69-88), nonmalignant respiratory disease (SMR = 70; 95% CI = 50-95), and cirrhosis of the liver (SMR = 44; 95% CI = 22-79). Mortality among employees who had 20 years or longer since their first potential exposure was also examined; the pattern of mortality was similar to that exhibited by the total cohort, with a slight increase in the SMR for most of the causes. The only statistically significant excess of mortality found was a fourfold increase in mesothelioma (5 observed and 1.2 expected deaths) the SMR was 428 (95% CI = 139-996) for the total cohort and was 469 (95% CI = 152-1093) for those who had 20 years or more since first potential exposure. In contrast to asbestos industry worker studies, mortality for lung cancer was substantially lower than the general population (SMR = 81; 95% CI = 63-103). The observed number of deaths for cancer of the larynx was virtually the same as expected (3 observed vs. 2.8 expected). This study also showed decreased mortality for cancers of gastrointestinal

  1. Maintenance carbon cycle in crassulacean Acid metabolism plant leaves : source and compartmentation of carbon for nocturnal malate synthesis.

    PubMed

    Kenyon, W H; Severson, R F; Black, C C

    1985-01-01

    The reciprocal relationship between diurnal changes in organic acid and storage carbohydrate was examined in the leaves of three Crassulacean acid metabolism plants. It was found that depletion of leaf hexoses at night was sufficient to account quantitatively for increase in malate in Ananas comosus but not in Sedum telephium or Kalanchoë daigremontiana. Fructose and to a lesser extent glucose underwent the largest changes. Glucose levels in S. telephium leaves oscillated diurnally but were not reciprocally related to malate fluctuations.Analysis of isolated protoplasts and vacuoles from leaves of A. comosus and S. telephium revealed that vacuoles contain a large percentage (>50%) of the protoplast glucose, fructose and malate, citrate, isocitrate, ascorbate and succinate. Sucrose, a major constituent of intact leaves, was not detectable or was at extremely low levels in protoplasts and vacuoles from both plants.In isolated vacuoles from both A. comosus and S. telephium, hexose levels decreased at night at the same time malate increased. Only in A. comosus, however, could hexose metabolism account for a significant amount of the nocturnal increase in malate. We conclude that, in A. comosus, soluble sugars are part of the daily maintenance carbon cycle and that the vacuole plays a dynamic role in the diurnal carbon assimilation cycle of this Crassulacean acid metabolism plant. PMID:16664005

  2. Antidepressant pharmacotherapy: economic evaluation of fluoxetine, paroxetine and sertraline in a health maintenance organization.

    PubMed

    Sclar, D A; Robison, L M; Skaer, T L; Galin, R S; Legg, R F; Nemec, N L; Hughes, T E; Buesching, D P; Morgan, M

    1995-01-01

    The present study was designed to compare direct health service expenditures, for the treatment of depression, among patients enrolled in a health maintenance organization, and prescribed one of three selective serotonin reuptake inhibitors, fluoxetine, paroxetine or sertraline. Information regarding depression-related health service use was derived from the computer archive of a network-model health maintenance organization system serving 700,000 beneficiaries. A total of 744 health maintenance organization beneficiaries were found to satisfy the study selection criteria. Multivariate regression analysis was used to determine the incremental influence of selected demographic, clinical, financial and provider characteristics on health service expenditures related to the treatment of depression (ICD-9-CM, or DSM-IV code 296.2) 1 year after the start of antidepressant pharmacotherapy. Multivariate findings indicate that treatment with paroxetine increases average expenditures for physician visits ($31.93; P < or = 0.05), psychiatric visits ($19.33; NS), laboratory tests ($2.35; P < or = 0.05), hospitalizations ($85.33; P < or = 0.05), psychiatric hospitalizations ($82.01; P < or = 0.05), and antidepressant pharmacotherapy ($63.72; P < or = 0.05), for a total per capita increase in health service use of $284.68 (P < or = 0.05), compared with treatment with fluoxetine. Sertraline treatment increases average expenditures for physician visits ($21.74; P < or = 0.05), psychiatric visits ($56.79; P < or = 0.05), laboratory tests ($1.21; P < or = 0.05), hospitalizations ($70.59; P < or = 0.05), psychiatric hospitalizations ($95.75; P < or = 0.05), and antidepressant pharmacotherapy ($69.85; P < or = 0.05), for a total per capita increase in health service use of $315.96 (P < or = 0.05), compared with treatment with fluoxetine. Economic comparisons between paroxetine and sertraline did not demonstrate any significant differences in expenditures for the health services

  3. Promoting child passenger safety in children served by a health maintenance organization.

    PubMed

    Chang, A; Hearey, C D; Gallagher, K D; English, P; Chang, P C

    1989-06-01

    A patient education program, based on the health belief model, promoting child passenger safety was developed and implemented at a health maintenance organization. The program included individual counseling by pediatricians, use of audiovisual materials and pamphlets, and (for newborn infants) a home visit by a child safety specialist. Based on parking lot observations, child safety device use increased to greater than 60% in both intervention and comparison-group children 1-4 years of age. During the child health supervision visit, pediatricians can play a leadership role in promoting child passenger safety. PMID:10293483

  4. Barriers to the health maintenance organization for the over 65's.

    PubMed

    Titus, S L

    1982-01-01

    What are the barriers that impede and prevent those over age 65 from considering a health maintenance organization (HMO) as an alternative to traditional Medicare-supplementary insurance? In an attempt to answer this question, structured interviews were conducted with 260 elderly people. The barriers examined include knowledge deficits lack of exposure to information, general resistance to change, the difficulties of integrating the 'new' with old insurance patterns, and value stances that may limit the adoption of HMOs by some elderly. Also discussed are educational strategies that may enhance the possibility of the elderly's consideration of the HMO as a viable option. PMID:6758126

  5. Social health maintenance organizations' service use and costs, 1985-89

    PubMed Central

    Harrington, Charlene; Newcomer, Robert J.

    1991-01-01

    Presented in this article are aggregate utilization and financial data from the four social health maintenance organization (SIHMO) demonstrations that were collected and analyzed as a part of the national evaluation of the SIHMO demonstration project conducted for the Health Care Financing Administration. The S/HMOs, in offering a $6,500 to $12,000 chronic care benefit in addition to the basic HMO benefit package, had higher startup costs and financial losses over the first 5 years than expected, and controlling costs continues to be a challenge to the sites and their sponsors. PMID:10113612

  6. Maintenance of xylem Network Transport Capacity: A Review of Embolism Repair in Vascular Plants

    PubMed Central

    Brodersen, Craig R.; McElrone, Andrew J.

    2013-01-01

    Maintenance of long distance water transport in xylem is essential to plant health and productivity. Both biotic and abiotic environmental conditions lead to embolism formation within the xylem resulting in lost transport capacity and ultimately death. Plants exhibit a variety of strategies to either prevent or restore hydraulic capacity through cavitation resistance with specialized anatomy, replacement of compromised conduits with new growth, and a metabolically active embolism repair mechanism. In recent years, mounting evidence suggests that metabolically active cells surrounding the xylem conduits in some, but not all, species are capable of restoring hydraulic conductivity. This review summarizes our current understanding of the osmotically driven embolism repair mechanism, the known genetic and anatomical components related to embolism repair, rehydration pathways through the xylem, and the role of capacitance. Anatomical differences between functional plant groups may be one of the limiting factors that allow some plants to refill while others do not, but further investigations are necessary to fully understand this dynamic process. Finally, xylem networks should no longer be considered an assemblage of dead, empty conduits, but instead a metabolically active tissue finely tuned to respond to ever changing environmental cues. PMID:23630539

  7. Final Report on the Operation and Maintenance Improvement Program for Concentrating Solar Power Plants

    SciTech Connect

    Cohen Gilbert E.; Kearney, David W.; Kolb, Gregory J.

    1999-06-01

    This report describes the results of a six-year, $6.3 million project to reduce operation and maintenance (O&M) costs at power plants employing concentrating solar power (CSP) technology. Sandia National Laboratories teamed with KJC Operating Company to implement the O&M Improvement Program. O&M technologies developed during the course of the program were demonstrated at the 150-MW Kramer Junction solar power park located in Boron, California. Improvements were made in the following areas: (a) efficiency of solar energy collection, (b) O&M information management, (c) reliability of solar field flow loop hardware, (d) plant operating strategy, and (e) cost reduction associated with environmental issues. A 37% reduction in annual O&M costs was achieved. Based on the lessons learned, an optimum solar- field O&M plan for future CSP plants is presented. Parabolic trough solar technology is employed at Kramer Junction. However, many of the O&M improvements described in the report are also applicable to CSP plants based on solar power tower or dish/engine concepts.

  8. FON2 SPARE1 Redundantly Regulates Floral Meristem Maintenance with FLORAL ORGAN NUMBER2 in Rice

    PubMed Central

    Suzaki, Takuya; Ohneda, Masako; Toriba, Taiyo; Yoshida, Akiko; Hirano, Hiro-Yuki

    2009-01-01

    CLAVATA signaling restricts stem cell identity in the shoot apical meristem (SAM) in Arabidopsis thaliana. In rice (Oryza sativa), FLORAL ORGAN NUMBER2 (FON2), closely related to CLV3, is involved as a signaling molecule in a similar pathway to negatively regulate stem cell proliferation in the floral meristem (FM). Here we show that the FON2 SPARE1 (FOS1) gene encoding a CLE protein functions along with FON2 in maintenance of the FM. In addition, FOS1 appears to be involved in maintenance of the SAM in the vegetative phase, because constitutive expression of FOS1 caused termination of the vegetative SAM. Genetic analysis revealed that FOS1 does not need FON1, the putative receptor of FON2, for its action, suggesting that FOS1 and FON2 may function in meristem maintenance as signaling molecules in independent pathways. Initially, we identified FOS1 as a suppressor that originates from O. sativa indica and suppresses the fon2 mutation in O. sativa japonica. FOS1 function in japonica appears to be compromised by a functional nucleotide polymorphism (FNP) at the putative processing site of the signal peptide. Sequence comparison of FOS1 in about 150 domesticated rice and wild rice species indicates that this FNP is present only in japonica, suggesting that redundant regulation by FOS1 and FON2 is commonplace in species in the Oryza genus. Distribution of the FNP also suggests that this mutation may have occurred during the divergence of japonica from its wild ancestor. Stem cell maintenance may be regulated by at least three negative pathways in rice, and each pathway may contribute differently to this regulation depending on the type of the meristem. This situation contrasts with that in Arabidopsis, where CLV signaling is the major single pathway in all meristems. PMID:19834537

  9. A system for the calculation and visualisation of radiation field for maintenance support in nuclear power plants.

    PubMed

    Ohga, Yukiharu; Fukuda, Mitsuko; Shibata, Kiyotaka; Kawakami, Takashi; Matsuzaki, Tomokazu

    2005-01-01

    A system has been developed to improve the efficiency of maintenance work while decreasing the radiation exposure of maintenance personnel in nuclear power plants. The input data for dose rate calculation are automatically generated by using computer-aided design data. Changes for the input data corresponding to the progress of maintenance work, such as installation of a radiation shield and removal of a component, are easily input interactively on a graphical user interface (GUI). A new method was proposed which searches the sets of source and detector points between which gamma-ray attenuation is changed by the component movement. The calculation is performed only for the changed sets, so that the change of the three-dimensional dose rate distribution is calculated rapidly according to the work progress. The dose rate distribution and the radiation exposure of maintenance personnel are displayed three-dimensionally in colour with plant components and pipes on the GUI. PMID:16604706

  10. Results of calendar year 1994 monitor well inspection and maintenance program, Y-12 Plant, Oak Ridge, Tennessee

    SciTech Connect

    McMaster, B.W.; Jones, S.B.; Sitzler, J.L.

    1995-06-01

    This document is a compendium of results of the calendar year 1994 Monitor Well Inspection and Maintenance Program at the Department of Energy Y-12 Plant in Oak Ridge, Tennessee. This report documents the work relating to well inspections and maintenance requests. Inspections are implemented in order to better assess the condition and maintenance needs of wells that are actively being monitored. Currently this approach calls for inspecting all wells on a routine (annual or triennial) basis which are: (1) in an active sampling program; (2) included in a hydrologic study; or (3) not in service, but not scheduled for plugging and abandonment. Routine inspections help to ensure that representative groundwater samples and hydrologic data are being collected, and contribute to the life expectancy of each well. This report formally presents well inspection and maintenance activities that were conducted at the Y-12 Plant during 1994. All inspections were conducted between April and December.

  11. Hospitals and Health Maintenance Organizations: An Analysis of the Minneapolis-St. Paul Experience

    PubMed Central

    Morrisey, Michael A.; Gibson, Geoffrey; Ashby, Cynthia S.

    1983-01-01

    Minneapolis-St. Paul is recognized as a prime example of health care competition. Policymakers and others have been asked to look to the Twin Cities as a model upon which to base new competitive initiatives in the health care sector. Yet little is known about the impact of Health Maintenance Organizations (HMOs) on other health care providers. This study examines the effects of the area's seven health maintenance organizations on the local hospital community. Three questions are addressed. First, is the situation in the Twin Cities unique? A comparison of case study findings and the available literature together with hospital data from similarly HMO-penetrated markets suggests that the Twin Cities' hospital market is indeed different. Second, what is the nature of hospital-HMO interaction? The flexibility of contracting apparently allows hospitals to affiliate successfully with an HMO under a variety of service and reimbursement agreements. Third, what effect has HMO activity had on community-wide utilization? While HMO enrollees clearly use fewer hospital days and the trend in the community is toward fewer days, attributing the change to HMOs is difficult. A large portion of the differences between HMO and community-wide utilization levels is attributable to differences in population. PMID:10309856

  12. Separation in flowering time contributes to the maintenance of sympatric cryptic plant lineages

    PubMed Central

    Michalski, Stefan G; Durka, Walter

    2015-01-01

    Sympatric cryptic lineages are a challenge for the understanding of species coexistence and lineage diversification as well as for management, conservation, and utilization of plant genetic resources. In higher plants studies providing insights into the mechanisms creating and maintaining sympatric cryptic lineages are rare. Here, using microsatellites and chloroplast sequence data, morphometric analyses, and phenological observations, we ask whether sympatrically coexisting lineages in the common wetland plant Juncus effusus are ecologically differentiated and reproductively isolated. Our results show two genetically highly differentiated, homoploid lineages within J. effusus that are morphologically cryptic and have similar preference for soil moisture content. However, flowering time differed significantly between the lineages contributing to reproductive isolation and the maintenance of these lineages. Furthermore, the later flowering lineage suffered less from predispersal seed predation by a Coleophora moth species. Still, we detected viable and reproducing hybrids between both lineages and the earlier flowering lineage and J. conglomeratus, a coexisting close relative. Flowering time differentiation between the lineages can be explained by neutral divergence alone and together with a lack of postzygotic isolation mechanisms; the sympatric coexistence of these lineages is most likely the result of an allopatric origin with secondary contact. PMID:26078854

  13. SURVEY OF OPERATION AND MAINTENANCE-RELATED MATERIALS NEEDS IN GEOTHERMAL POWER PLANTS

    SciTech Connect

    ALLAN,M.L.

    1998-06-01

    A survey was conducted to determine operation and maintenance (O and M)-related materials needs in geothermal power plants and to identify future research and development to address these needs. A total of 44 questionnaires was mailed to geothermal plant operators and industry consultants. The response rate was 54%. The participants were asked to describe type and frequency of materials problems, strategies currently used to mitigate such problems, barriers to using new or alternative materials and technologies, sources of information and give their views research and development priorities. A. wide range of opinions was obtained, reflecting each individual respondent's perspective and the site-specific nature of some problems. However, the consensus is that corrosion and scaling remain major issues and that components requiring performance improvements include pipelines, well casing, turbines, heat exchangers, condensers, valves and cooling towers. It is recommended that appropriate research and development continue to be directed at reducing O and M costs associated with materials failure or inadequate service. There should be a balance between optimizing existing materials through better design and understanding of behavior in geothermal environments and development of new materials. Life extension of existing equipment, service life prediction, education of plant personnel in materials and methods for mitigating corrosion, and improvements in inhibitors and biocides would also be beneficial.

  14. Survey of operation and maintenance-related materials needs in geothermal power plants

    SciTech Connect

    Allan, M.L.

    1998-06-01

    A survey was conducted to determine operation and maintenance (O and M)-related materials needs in geothermal power plants and to identify future research and development to address these needs. A total of 44 questionnaires was mailed to geothermal plant operators and industry consultants. The response rate was 54%. The participants were asked to describe type and frequency of materials problems, strategies currently used to mitigate such problems, barriers to using new or alternative materials and technologies, sources of information and give their views on research and development priorities. A wide range of opinions was obtained, reflecting each individual respondent`s perspective and the site-specific nature of some problems. However, the consensus is that corrosion and scaling remain major issues and that components requiring performance improvements include pipelines, well casing, turbines, heat exchangers, condensers, valves and cooling towers. It is recommended that appropriate research and development continue to be directed at reducing O and M costs associated with materials failure or inadequate service. There should be a balance between optimizing existing materials through better design and understanding of behavior in geothermal environments and development of new materials. Life extension of existing equipment, service life prediction, education of plant personnel in materials and methods for mitigating corrosion, and improvements in inhibitors and biocides would also be beneficial.

  15. Effect of coal quality on maintenance costs at utility plants. Final report. [Effect of ash and sulfur content of coal

    SciTech Connect

    Holt, E.C. Jr.

    1980-06-01

    In an attempt to determine if correlation exists between coal quality, as measured by its ash and sulfur contents, and the maintenance cost at utility plants, an examination was made of the actual maintenance cost experience of selected portions of five TVA coal-fired power plants as a function of the fuel quality consumed during an extended period of time. The results indicate that, according to our decision rules developed in compliance with accepted statistical practices, correlation does exist in many portions of the coal-fired plants for which sufficient maintenance cost records were available. The degree of correlation varies significantly among the individual portions of a particular plant as well as among the various plants. However, the indicators are sufficient to confirm that a change (within the design constraints of the unit) in the ash and/or sulfur content of the coal being consumed by a utility boiler will have a proportionate effect on the maintenance cost at the plant. In the cases examined, each percent variation in ash content could have a monetary effect of from $0.05 to $0.10 per ton of coal consumed. Similarly, each percent variation in sulfur content could influence maintenance costs from $0.30 to $0.50 per ton of coal. Since these values are based on preliminary analysis of limited data, they must be approached with caution and not removed from the context in which they are presented. However, if borne out by further study, the potential magnitude of such savings may be sufficient to justify the acquisition of superior coal supplies, either by changing the source and/or using preparation to obtain a lower ash and sulfur fuel.

  16. Transfer of infrared thermography predictive maintenance technologies to Soviet-designed nuclear power plants: experience at Chernobyl

    NASA Astrophysics Data System (ADS)

    Pugh, Ray; Huff, Roy

    1999-03-01

    The importance of infrared (IR) technology and analysis in today's world of predictive maintenance and reliability- centered maintenance cannot be understated. The use of infrared is especially important in facilities that are required to maintain a high degree of equipment reliability because of plant or public safety concerns. As with all maintenance tools, particularly those used in predictive maintenance approaches, training plays a key role in their effectiveness and the benefit gained from their use. This paper details an effort to transfer IR technology to Soviet- designed nuclear power plants in Russia, Ukraine, and Lithuania. Delivery of this technology and post-delivery training activities have been completed recently at the Chornobyl nuclear power plant in Ukraine. Many interesting challenges were encountered during this effort. Hardware procurement and delivery of IR technology to a sensitive country were complicated by United States regulations. Freight and shipping infrastructure and host-country customs policies complicated hardware transport. Training activities were complicated by special hardware, software and training material translation needs, limited communication opportunities, and site logistical concerns. These challenges and others encountered while supplying the Chornobyl plant with state-of-the-art IR technology are described in this paper.

  17. 78 FR 58574 - Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-24

    ... identification as Draft Regulatory Guide, DG-1269, in the Federal Register on March 12, 2013 (78 FR 15753), for a... COMMISSION Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power..., Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power Plants.'' The...

  18. Plant Diseases and Management Approaches in Organic Farming Systems.

    PubMed

    van Bruggen, A H C; Finckh, M R

    2016-08-01

    Organic agriculture has expanded worldwide. Numerous papers were published in the past 20 years comparing plant diseases in organic and conventional crops. Root diseases are generally less severe owing to greater soil health, whereas some foliar diseases can be problematic in organic agriculture. The soil microbial community and nitrogen availability play an important role in disease development and yield. Recently, the focus has shifted to optimizing organic crop production by improving plant nutrition, weed control, and plant health. Crop-loss assessment relating productivity to all yield-forming and -reducing factors would benefit organic production and sustainability evaluation. PMID:27215969

  19. Twelve years of repeated wild hog activity promotes population maintenance of an invasive clonal plant in a coastal dune ecosystem.

    PubMed

    Oldfield, Callie A; Evans, Jonathan P

    2016-04-01

    Invasive animals can facilitate the success of invasive plant populations through disturbance. We examined the relationship between the repeated foraging disturbance of an invasive animal and the population maintenance of an invasive plant in a coastal dune ecosystem. We hypothesized that feral wild hog (Sus scrofa) populations repeatedly utilized tubers of the clonal perennial, yellow nutsedge (Cyperus esculentus) as a food source and evaluated whether hog activity promoted the long-term maintenance of yellow nutsedge populations on St. Catherine's Island, Georgia, United States. Using generalized linear mixed models, we tested the effect of wild hog disturbance on permanent sites for yellow nutsedge culm density, tuber density, and percent cover of native plant species over a 12-year period. We found that disturbance plots had a higher number of culms and tubers and a lower percentage of native live plant cover than undisturbed control plots. Wild hogs redisturbed the disturbed plots approximately every 5 years. Our research provides demographic evidence that repeated foraging disturbances by an invasive animal promote the long-term population maintenance of an invasive clonal plant. Opportunistic facultative interactions such as we demonstrate in this study are likely to become more commonplace as greater numbers of introduced species are integrated into ecological communities around the world. PMID:27110354

  20. Impact of mechanical- and maintenance-induced failures of main reactor coolant pump seals on plant safety

    SciTech Connect

    Azarm, M A; Boccio, J L; Mitra, S

    1985-12-01

    This document presents an investigation of the safety impact resulting from mechanical- and maintenance-induced reactor coolant pump (RCP) seal failures in nuclear power plants. A data survey of the pump seal failures for existing nuclear power plants in the US from several available sources was performed. The annual frequency of pump seal failures in a nuclear power plant was estimated based on the concept of hazard rate and dependency evaluation. The conditional probability of various sizes of leak rates given seal failures was then evaluated. The safety impact of RCP seal failures, in terms of contribution to plant core-melt frequency, was also evaluated for three nuclear power plants. For leak rates below the normal makeup capacity and the impact of plant safety were discussed qualitatively, whereas for leak rates beyond the normal make up capacity, formal PRA methodologies were applied. 22 refs., 17 figs., 19 tabs.

  1. An analysis of the radiation field characteristics for extremity dose assessment during maintenance periods at nuclear power plants in Korea.

    PubMed

    Kim, Hee Geun; Kong, Tae Young

    2012-12-01

    Workers who maintain the water chambers of steam generators during maintenance periods in nuclear power plants (NPPs) have a higher likelihood of high radiation exposure, even if they are exposed for a short period of time. In particular, it is expected that the hands of workers would receive the highest radiation exposure as a consequence of hand contact with radioactive materials. In this study, a characteristic analysis of inhomogeneous radiation fields for contact operations was conducted using thermoluminescent dosemeters for the whole body and extremities during maintenance periods at Korean NPPs. It was observed that inhomogeneous radiation fields for contact operations at NPPs were dominated by high-energy photons. PMID:22628525

  2. ENZYMATIC PROCESSES USED BY PLANTS TO DEGRADE ORGANIC COMPOUNDS

    EPA Science Inventory

    This is a review of recent plant enzyme systems that have been studied in uptake and transformation of organic contaminants. General procedures of plant preparation and enzyme isolation are covered. Six plant enzyme systems have been investigated for activity with selected pollut...

  3. Maintenance Business Plans.

    ERIC Educational Resources Information Center

    Adams, Matt

    2002-01-01

    Discusses maintenance business plans, statements which provide accountability for facilities maintenance organizations' considerable budgets. Discusses the plan's components: statement of plan objectives, macro and detailed description of the facility assets, maintenance function descriptions, description of key performance indicators, milestone…

  4. Health Maintenance Organizations and Academic Medical Centers. Proceedings of a National Conference (Colorado Springs, Colorado, October 1980).

    ERIC Educational Resources Information Center

    Hudson, James I., Ed.; Nevins, Madeline M., Ed.

    In October 1980 a national conference on health maintenance organizations (HMOs) and Academic Medical Centers (AMCs) was held by the Association of American Medical Colleges and supported by the Henry J. Kaiser Family Foundation, in response to inquiries about the advantages and disadvantages of AMC affiliation with or sponsorship of HMOs.…

  5. An Educational Program for Sub-Professional Personnel to be Employed in Health Maintenance Organizations. Final Report.

    ERIC Educational Resources Information Center

    HMO Management, Inc., Los Angeles, CA.

    Through Medicaid, the Health Maintenance Organization Act (HMO), and Prepaid Health Programs (PHP) approaches were established whereby the government can help alleviate the medical problems of the needy. A program to educate and train students in California in the philosophy, administration, and development of PHP was developed in response to…

  6. [Health maintenance organizations: starting point of a market economical reform of health care].

    PubMed

    Hauser, H

    1981-05-01

    The present work was based on the observations that, as regards health care costs, the major problem in most present systems is that those who are responsible for the treatment decision (physician and patient) do not bear a direct financial responsibility for it, and that the overall system is very fragmented, which leads to numerous externalities. In accordance with this diagnosis, a reform strategy should particularly aim at creating units which are responsible for the provision and the financial coverage of comprehensive health services to a given population. Health Maintenance Organizations (HMOs) are a private economy oriented solution in this direction. They have proved to be a real possibility in the USA over years, at least for part of the population, and show interesting performances as regards costs. They were able to develop and evolve in the largely open US institutional framework. In Switzerland, we have more strongly structured systems, which appear to stand in relative contradiction to the HMO solution. A potential adaptation of the concept to our country would therefore require a preliminary in depth discussion about the meaning of the present collective (insurance) contract structure, the position of hospitals in a private economy health care system as well as about the conditions of the sought for competition in the HMO model. PMID:7303928

  7. Out-of-plan use by Medicare enrollees in a risk-sharing health maintenance organization

    PubMed Central

    Haglund, Claudia L.; Martin, Diane P.; Diehr, Paula; Johnston, Ric; Richardson, William C.

    1985-01-01

    In this study, we analyzed the cost and volume effects of a waiver that eliminated lock-in restrictions on out-of-plan use in a health maintenance organization (HMO) with a Medicare risk-sharing contract. We compared out-of-plan cost and number of claims during a 15-month base line period when the lock-in was in effect, with a 24-month waiver period when the lock-in was removed. The results demonstrate that average per capita cost and claims increased significantly for both Medicare Part A (hospital insurance) and Part B (supplementary medical insurance) out-of-plan services during the waiver. Self-referred out-of-plan use normally prohibited by lock-in, accounted for 20 percent of all out-of-plan costs during the waiver and 57 percent of the increase in out-of-plan costs from the lock-in to the waiver. The combination of risk-sharing and lock-in provisions holds promise as a method for reducing expenditures for the Medicare program. PMID:10311436

  8. Comprehensive pharmaceutical services in the outpatient surgery center of a health maintenance organization.

    PubMed

    Kollar, K M; Deady, J E; Dillon, M J

    1990-02-01

    The pharmaceutical services provided to the outpatient surgery center of a health maintenance organization (HMO) are described. The satellite pharmacy is managed by the nearby central pharmacy. The satellite pharmacist prepares and dispenses all needed medications and i.v. admixtures, maintains the inventory of all drugs and i.v. supplies, and supplies clinical and drug information. The pharmacist ensures that i.v. admixtures are made according to guidelines, that drug interactions and drug allergies are guarded against, and that each patient has access to oral pain medications and medication counseling while still in the recovery room. The tighter inventory control created by this arrangement helps to reduce costs, and the surgical nursing staff has been relieved of many medication-related activities. The presence of the pharmacist in the surgery center also allows for more accurate documentation of controlled-drug dispensing. The presence of a pharmacist in the surgery center has ensured strict control of drug use and enabled nurses to spend more time on direct patient care. PMID:2309723

  9. Competition between health maintenance organizations and nonintegrated health insurance companies in health insurance markets.

    PubMed

    Baranes, Edmond; Bardey, David

    2015-12-01

    This article examines a model of competition between two types of health insurer: Health Maintenance Organizations (HMOs) and nonintegrated insurers. HMOs vertically integrate health care providers and pay them at a competitive price, while nonintegrated health insurers work as indemnity plans and pay the health care providers freely chosen by policyholders at a wholesale price. Such difference is referred to as an input price effect which, at first glance, favors HMOs. Moreover, we assume that policyholders place a positive value on the provider diversity supplied by their health insurance plan and that this value increases with the probability of disease. Due to the restricted choice of health care providers in HMOs a risk segmentation occurs: policyholders who choose nonintegrated health insurers are characterized by higher risk, which also tends to favor HMOs. Our equilibrium analysis reveals that the equilibrium allocation only depends on the number of HMOs in the case of exclusivity contracts between HMOs and providers. Surprisingly, our model shows that the interplay between risk segmentation and input price effects may generate ambiguous results. More precisely, we reveal that vertical integration in health insurance markets may decrease health insurers' premiums. PMID:26608954

  10. Revalidation of the Volatile Organic Analyzer Following a Major On-Orbit Maintenance Activity

    NASA Technical Reports Server (NTRS)

    Limero, Thomas; James, John T.

    2007-01-01

    The Volatile Organic Analyzer (VOA) contributes to the assessment of air quality aboard the International Space Station (ISS) by identifying and quantifying target airborne volatile organic contaminants in the module air. This on-orbit contaminant monitoring capability becomes particularly important during an air quality degradation event such as a system leak. During several ISS air quality degradations, the VOA has generated near real-time data that was used to make decisions or to better understand the contingency. The VOA was operational from January 2002 through June 2003, during which time it was validated by comparing VOA data to simultaneously acquired grab sample containers (GSCs). In January 2003, one of the two analytical channels of the VOA was shutdown because of a component failure, but a redundant channel continued to supply the necessary analytical data. In June 2003, the sole remaining channel was deactivated. Initial assessments of the channel shutdowns pointed to failed fuses or heaters, but neither was considered repairable on orbit. In 2005, it was determined that failed fuses could be replaced on orbit and the crew conducted a diagnostic procedure to identify the failed component. The crew discovered that both channels incurred failed fuses, which lead to a subsequent on orbit maintenance activity and return of the VOA to operational status in December 2005. The VOA has been providing data on the ISS atmosphere since its reactivation in 2005 and this paper will present the VOA data collected during 2006. Special emphasis will be placed upon the revalidation of the repaired VOA using GSCs as well as a summary of the diagnostic and repair procedures.

  11. Soil Organic Matter and Management of Plant-Parasitic Nematodes

    PubMed Central

    Widmer, T. L.; Mitkowski, N. A.; Abawi, G. S.

    2002-01-01

    Organic matter and its replenishment has become a major component of soil health management programs. Many of the soil's physical, chemical, and biological properties are a function of organic matter content and quality. Adding organic matter to soil influences diverse and important biological activities. The diversity and number of free-living and plant-parasitic nematodes are altered by rotational crops, cover crops, green manures, and other sources of organic matter. Soil management programs should include the use of the proper organic materials to improve soil chemical, physical, and biological parameters and to suppress plant-parasitic nematodes and soilborne pathogens. It is critical to monitor the effects of organic matter additions on activities of major and minor plant-parasitic nematodes in the production system. This paper presents a general review of information in the literature on the effects of crop rotation, cover crops, and green manures on nematodes and their damage to economic crops. PMID:19265946

  12. Soil organic matter and management of plant-parasitic nematodes.

    PubMed

    Widmer, T L; Mitkowski, N A; Abawi, G S

    2002-12-01

    Organic matter and its replenishment has become a major component of soil health management programs. Many of the soil's physical, chemical, and biological properties are a function of organic matter content and quality. Adding organic matter to soil influences diverse and important biological activities. The diversity and number of free-living and plant-parasitic nematodes are altered by rotational crops, cover crops, green manures, and other sources of organic matter. Soil management programs should include the use of the proper organic materials to improve soil chemical, physical, and biological parameters and to suppress plant-parasitic nematodes and soilborne pathogens. It is critical to monitor the effects of organic matter additions on activities of major and minor plant-parasitic nematodes in the production system. This paper presents a general review of information in the literature on the effects of crop rotation, cover crops, and green manures on nematodes and their damage to economic crops. PMID:19265946

  13. An examination of maintenance activities in liquid metal reactor facilities: An analysis by the Centralized Reliability Data Organization (CREDO)

    SciTech Connect

    Haire, M J; Knee, H E; Manning, J J; Manneschmidt, J F; Setoguchi, K

    1987-01-01

    The Centralized Reliability Data Organization (CREDO) is the largest repository of liquid metal reactor (LMR) component reliability data in the world. It is jointly sponsored by the US Department of Energy (DOE) and the Power Reactor and Nuclear fuel Development Corporation (PNC) of Japan. The CREDO database contains information on a population of more than 21,000 components and approximately 1300 event records. Total experience is approaching 1.2 billion component operating hours. Although data gathering for CREDO concentrates on event (failure) information, the work reported here focuses on the maintenance information contained in CREDO and the development of maintenance critical items lists. That is, components are ranked in prioritized lists from worse to best performers from a maintenance standpoint.

  14. An analysis of the impacts of economic incentive programs on commercial nuclear power plant operations and maintenance costs

    SciTech Connect

    Kavanaugh, D.C.; Monroe, W.H.; Wood, R.S.

    1996-02-01

    Operations and Maintenance (O and M) expenditures by nuclear power plant owner/operators possess a very logical and vital link in considerations relating to plant safety and reliability. Since the determinants of O and M outlays are considerable and varied, the potential linkages to plant safety, both directly and indirectly, can likewise be substantial. One significant issue before the US Nuclear Regulatory Commission is the impact, if any, on O and M spending from state programs that attempt to improve plant operating performance, and how and to what extent these programs may affect plant safety and pose public health risks. The purpose of this study is to examine the role and degree of impacts from state promulgated economic incentive programs (EIPs) on plant O and M spending. A multivariate regression framework is specified, and the model is estimated on industry data over a five-year period, 1986--1990. Explanatory variables for the O and M spending model include plant characteristics, regulatory effects, financial strength factors, replacement power costs, and the performance incentive programs. EIPs are found to have statistically significant effects on plant O and M outlays, albeit small in relation to other factors. Moreover, the results indicate that the relatively financially weaker firms are more sensitive in their O and M spending to the presence of such programs. Formulations for linking spending behavior and EIPs with plant safety performance remains for future analysis.

  15. A remote telepresence robotic system for inspection and maintenance of a nuclear power plant

    SciTech Connect

    Crane, C.D. III; Tulenko, J.S.

    1993-02-01

    Progress in reported in the areas of environmental hardening; database/world modeling; man-machine interface; development of the Advanced Liquid Metal Reactor (ALMR) maintenance inspection robot design; and Articulated Transporter/Manipulator System (ATMS) development.

  16. Does Accelerated Soil Organic Matter Decomposition in the Presence of Plants Increase Plant N Availability?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant roots can increase microbial activity and soil organic matter (SOM) decomposition via rhizosphere priming effects. It is virtually unknown how differences in the priming effect among plant species and soil type affect N mineralization and plant uptake. In a greenhouse experiment, we tested whe...

  17. Engrailed 1 shapes the dopaminergic and serotonergic landscape through proper isthmic organizer maintenance and function.

    PubMed

    Kouwenhoven, Willemieke M; Veenvliet, Jesse V; van Hooft, Johannes A; van der Heide, L P; Smidt, Marten P

    2016-01-01

    The isthmic organizer (IsO) is a signaling center that specifies the correct and distinct embryonic development of the dopaminergic midbrain and serotonergic hindbrain. The IsO is a linear boundary between the two brain regions, emerging at around embryonic day 7-8 of murine embryonic development, that shapes its surroundings through the expression of instructive signals such as Wnt and growth factors. Homeobox transcription factor engrailed 1 (En1) is present in midbrain and rostral hindbrain (i.e. rhombomere 1, R1). Its expression spans the IsO, and it is known to be an important survival factor for both dopaminergic and serotonergic neurons. Erroneous composition of dopaminergic neurons in the midbrain or serotonergic neurons in the hindbrain is associated with severe pathologies such as Parkinson's disease, depression or autism. Here we investigated the role of En1 in early mid-hindbrain development, using multiple En1-ablated mouse models as well as lineage-tracing techniques, and observed the appearance of ectopic dopaminergic neurons, indistinguishable from midbrain dopaminergic neurons based on molecular profile and intrinsic electrophysiological properties. We propose that this change is the direct result of a caudal relocation of the IsO as represented by ectopic presence of Fgf8, Otx2, Wnt1 and canonical Wnt-signalling. Our work suggests a newly-discovered role for En1: the repression of Otx2, Wnt1 and canonical Wnt-signaling in R1. Overall, our results suggest that En1 is essential for proper IsO maintenance and function. PMID:26879466

  18. Engrailed 1 shapes the dopaminergic and serotonergic landscape through proper isthmic organizer maintenance and function

    PubMed Central

    Kouwenhoven, Willemieke M.; Veenvliet, Jesse V.; van Hooft, Johannes A.; van der Heide, L. P.; Smidt, Marten P.

    2016-01-01

    ABSTRACT The isthmic organizer (IsO) is a signaling center that specifies the correct and distinct embryonic development of the dopaminergic midbrain and serotonergic hindbrain. The IsO is a linear boundary between the two brain regions, emerging at around embryonic day 7-8 of murine embryonic development, that shapes its surroundings through the expression of instructive signals such as Wnt and growth factors. Homeobox transcription factor engrailed 1 (En1) is present in midbrain and rostral hindbrain (i.e. rhombomere 1, R1). Its expression spans the IsO, and it is known to be an important survival factor for both dopaminergic and serotonergic neurons. Erroneous composition of dopaminergic neurons in the midbrain or serotonergic neurons in the hindbrain is associated with severe pathologies such as Parkinson's disease, depression or autism. Here we investigated the role of En1 in early mid-hindbrain development, using multiple En1-ablated mouse models as well as lineage-tracing techniques, and observed the appearance of ectopic dopaminergic neurons, indistinguishable from midbrain dopaminergic neurons based on molecular profile and intrinsic electrophysiological properties. We propose that this change is the direct result of a caudal relocation of the IsO as represented by ectopic presence of Fgf8, Otx2, Wnt1 and canonical Wnt-signalling. Our work suggests a newly-discovered role for En1: the repression of Otx2, Wnt1 and canonical Wnt-signaling in R1. Overall, our results suggest that En1 is essential for proper IsO maintenance and function. PMID:26879466

  19. Innovation for maintenance technology improvements

    NASA Technical Reports Server (NTRS)

    Shives, T. R. (Editor); Willard, W. A. (Editor)

    1982-01-01

    A group of 34 submitted entries (32 papers and 2 abstracts) from the 33rd meeting of the Mechanical Failures Prevention Group whose subject was maintenance technology improvement through innovation. Areas of special emphasis included maintenance concepts, maintenance analysis systems, improved maintenance processes, innovative maintenance diagnostics and maintenance indicators, and technology improvements for power plant applications.

  20. Regional Comparative Unit Cost Studies for Maintenance and Operation of Physical Plants in Universities and Colleges in Central States Region and Rocky Mountain Region.

    ERIC Educational Resources Information Center

    Association of Physical Plant Administrators, Corvallis, OR.

    Presented in this document are data pertaining to maintenance and operations costs at colleges and universities in the central states region and the Rocky Mountain region. The major accounts included in the cost analysis are: (1) physical plant administration, (2) building maintenance, (3) custodial services, (4) utilities, (5) landscape and…

  1. Organic Matter Application Can Reduce Copper Toxicity in Tomato Plants

    ERIC Educational Resources Information Center

    Campbell, Brian

    2010-01-01

    Copper fungicides and bactericides are often used in tomato cultivation and can cause toxic Cu levels in soils. In order to combat this, organic matter can be applied to induce chelation reactions and form a soluble complex by which much of the Cu can leach out of the soil profile or be taken up safely by plants. Organic acids such as citric,…

  2. The Haustorium, a Specialized Invasive Organ in Parasitic Plants.

    PubMed

    Yoshida, Satoko; Cui, Songkui; Ichihashi, Yasunori; Shirasu, Ken

    2016-04-29

    Parasitic plants thrive by infecting other plants. Flowering plants evolved parasitism independently at least 12 times, in all cases developing a unique multicellular organ called the haustorium that forms upon detection of haustorium-inducing factors derived from the host plant. This organ penetrates into the host stem or root and connects to its vasculature, allowing exchange of materials such as water, nutrients, proteins, nucleotides, pathogens, and retrotransposons between the host and the parasite. In this review, we focus on the formation and function of the haustorium in parasitic plants, with a specific emphasis on recent advances in molecular studies of root parasites in the Orobanchaceae and stem parasites in the Convolvulaceae. PMID:27128469

  3. Equipment Categorization as a Basis to Improve the Organization of Maintenance

    NASA Astrophysics Data System (ADS)

    Drahňovský, Juraj

    2012-12-01

    Each enterprise must worry about its technical equipment. There are many concepts and strategies to improve the management of the maintenance, e. g. TPM, RBI, LCC, CBM, RCM etc. However, the basis for each one of these systems should be the equipment categorization. The purpose of categorization is to classify equipments according to the type of risk associated with their main function. This allows to focus attention on the parameters and the criteria used to assign the degree of risk when the equipment fails and to determine the proper method of maintenance.

  4. A Basic Manual for Physical Plant Administration.

    ERIC Educational Resources Information Center

    Weber, George O., Ed.; Fincham, Michael W., Ed.

    This book provides practical advice on problems of institutional plant management to physical plant administrators. Areas covered include the role, organization, and facilities of the physical plant department; personnel administration; financial administration; buildings maintenance and operation; custodial services; utilities distribution…

  5. Hydrogen isotopic compositions of organic compounds in plants reflect the plant's carbon metabolism

    NASA Astrophysics Data System (ADS)

    Cormier, M. A.; Kahmen, A.; Werner, R. A.

    2015-12-01

    The main factors controlling δ2H of plant organic compounds are generally assumed to be the plant's source water and the evaporative deuterium enrichment of leaf water. Hydrogen isotope analyses of plant compounds from sediments or tree rings are therefore mainly applied to assess hydrological conditions at different spatial and temporal scales. However, the biochemical hydrogen isotope fractionation occurring during biosynthesis of plant organic compounds (ɛbio) also accounts for a large part of the variability observed in the δ2H values. Nevertheless, only few studies have directly addressed the physiological basis of this variability and even fewer studies have thus explored possible applications of hydrogen isotope variability in plant organic compounds for plant physiological research. Here we show two datasets indicating that the plant's carbon metabolism can have a substantial influence on δ2H values of n-alkanes and cellulose. First, we performed a controlled experiment where we forced plants into heterotrophic and autotrophic C-metabolism by growing them under four different light treatments. Second, we assessed the δ2H values of different parasitic heterotrophic plants and their autotrophic host plants. Our two datasets show a systematic shift in ɛbio of up to 80 ‰ depending on the plant's carbon metabolism (heterotrophic or autotrophic). Differences in n-alkane and cellulose δ2H values in plants with autotrophic vs. heterotrophic metabolisms can be explained by different NADPH pools that are used by the plants to build their compounds either with assimilates that originate directly from photosynthesis or from stored carbohydrates. Our results have significant implications for the calibration and interpretation of geological records. More importantly, as the δ2H values reflect the plant's carbon metabolism involved during the tissue formation, our findings highlight the potential of δ2H values as new tool for studying plant and ecosystem carbon

  6. Differential Effect of Plant Lipids on Membrane Organization

    PubMed Central

    Grosjean, Kevin; Mongrand, Sébastien; Beney, Laurent; Simon-Plas, Françoise; Gerbeau-Pissot, Patricia

    2015-01-01

    The high diversity of the plant lipid mixture raises the question of their respective involvement in the definition of membrane organization. This is particularly the case for plant plasma membrane, which is enriched in specific lipids, such as free and conjugated forms of phytosterols and typical phytosphingolipids, such as glycosylinositolphosphoceramides. This question was here addressed extensively by characterizing the order level of membrane from vesicles prepared using various plant lipid mixtures and labeled with an environment-sensitive probe. Fluorescence spectroscopy experiments showed that among major phytosterols, campesterol exhibits a stronger ability than β-sitosterol and stigmasterol to order model membranes. Multispectral confocal microscopy, allowing spatial analysis of membrane organization, demonstrated accordingly the strong ability of campesterol to promote ordered domain formation and to organize their spatial distribution at the membrane surface. Conjugated sterol forms, alone and in synergy with free sterols, exhibit a striking ability to order membrane. Plant sphingolipids, particularly glycosylinositolphosphoceramides, enhanced the sterol-induced ordering effect, emphasizing the formation and increasing the size of sterol-dependent ordered domains. Altogether, our results support a differential involvement of free and conjugated phytosterols in the formation of ordered domains and suggest that the diversity of plant lipids, allowing various local combinations of lipid species, could be a major contributor to membrane organization in particular through the formation of sphingolipid-sterol interacting domains. PMID:25575593

  7. Analysis of failure and maintenance experiences of motor operated valves in a Finnish nuclear power plant

    NASA Astrophysics Data System (ADS)

    Simola, Kaisa; Laakso, Kari

    1992-01-01

    Eight years of operating experiences of 104 motor operated closing valves in different safety systems in nuclear power units were analyzed in a systematic way. The qualitative methods used were Failure Mode and Effect Analysis (FMEA) and Maintenance Effects and Criticality Analysis (MECA). These reliability engineering methods are commonly used in the design stage of equipment. The successful application of these methods for analysis and utilization of operating experiences was demonstrated.

  8. Methods in plant foliar volatile organic compounds research.

    PubMed

    Materić, Dušan; Bruhn, Dan; Turner, Claire; Morgan, Geraint; Mason, Nigel; Gauci, Vincent

    2015-12-01

    Plants are a major atmospheric source of volatile organic compounds (VOCs). These secondary metabolic products protect plants from high-temperature stress, mediate in plant-plant and plant-insect communication, and affect our climate globally. The main challenges in plant foliar VOC research are accurate sampling, the inherent reactivity of some VOC compounds that makes them hard to detect directly, and their low concentrations. Plant VOC research relies on analytical techniques for trace gas analysis, usually based on gas chromatography and soft chemical ionization mass spectrometry. Until now, these techniques (especially the latter one) have been developed and used primarily by physicists and analytical scientists, who have used them in a wide range of scientific research areas (e.g., aroma, disease biomarkers, hazardous compound detection, atmospheric chemistry). The interdisciplinary nature of plant foliar VOC research has recently attracted the attention of biologists, bringing them into the field of applied environmental analytical sciences. In this paper, we review the sampling methods and available analytical techniques used in plant foliar VOC research to provide a comprehensive resource that will allow biologists moving into the field to choose the most appropriate approach for their studies. PMID:26697273

  9. Repression of Lateral Organ Boundary Genes by PENNYWISE and POUND-FOOLISH Is Essential for Meristem Maintenance and Flowering in Arabidopsis1[OPEN

    PubMed Central

    Khan, Madiha; Ragni, Laura; Tabb, Paul; Salasini, Brenda C.; Chatfield, Steven; Datla, Raju; Lock, John; Kuai, Xiahezi; Després, Charles; Proveniers, Marcel; Yongguo, Cao; Xiang, Daoquan; Morin, Halima; Rullière, Jean-Pierre; Citerne, Sylvie; Hepworth, Shelley R.; Pautot, Véronique

    2015-01-01

    In the model plant Arabidopsis (Arabidopsis thaliana), endogenous and environmental signals acting on the shoot apical meristem cause acquisition of inflorescence meristem fate. This results in changed patterns of aerial development seen as the transition from making leaves to the production of flowers separated by elongated internodes. Two related BEL1-like homeobox genes, PENNYWISE (PNY) and POUND-FOOLISH (PNF), fulfill this transition. Loss of function of these genes impairs stem cell maintenance and blocks internode elongation and flowering. We show here that pny pnf apices misexpress lateral organ boundary genes BLADE-ON-PETIOLE1/2 (BOP1/2) and KNOTTED-LIKE FROM ARABIDOPSIS THALIANA6 (KNAT6) together with ARABIDOPSIS THALIANA HOMEOBOX GENE1 (ATH1). Inactivation of genes in this module fully rescues pny pnf defects. We further show that BOP1 directly activates ATH1, whereas activation of KNAT6 is indirect. The pny pnf restoration correlates with renewed accumulation of transcripts conferring floral meristem identity, including FD, SQUAMOSA PROMOTER-BINDING PROTEIN LIKE genes, LEAFY, and APETALA1. To gain insight into how this module blocks flowering, we analyzed the transcriptome of BOP1-overexpressing plants. Our data suggest a central role for the microRNA156-SQUAMOSA PROMOTER BINDING PROTEIN-LIKE-microRNA172 module in integrating stress signals conferred in part by promotion of jasmonic acid biosynthesis. These data reveal a potential mechanism by which repression of lateral organ boundary genes by PNY-PNF is essential for flowering. PMID:26417006

  10. Repression of Lateral Organ Boundary Genes by PENNYWISE and POUND-FOOLISH Is Essential for Meristem Maintenance and Flowering in Arabidopsis.

    PubMed

    Khan, Madiha; Ragni, Laura; Tabb, Paul; Salasini, Brenda C; Chatfield, Steven; Datla, Raju; Lock, John; Kuai, Xiahezi; Després, Charles; Proveniers, Marcel; Yongguo, Cao; Xiang, Daoquan; Morin, Halima; Rullière, Jean-Pierre; Citerne, Sylvie; Hepworth, Shelley R; Pautot, Véronique

    2015-11-01

    In the model plant Arabidopsis (Arabidopsis thaliana), endogenous and environmental signals acting on the shoot apical meristem cause acquisition of inflorescence meristem fate. This results in changed patterns of aerial development seen as the transition from making leaves to the production of flowers separated by elongated internodes. Two related BEL1-like homeobox genes, PENNYWISE (PNY) and POUND-FOOLISH (PNF), fulfill this transition. Loss of function of these genes impairs stem cell maintenance and blocks internode elongation and flowering. We show here that pny pnf apices misexpress lateral organ boundary genes BLADE-ON-PETIOLE1/2 (BOP1/2) and KNOTTED-LIKE FROM ARABIDOPSIS THALIANA6 (KNAT6) together with ARABIDOPSIS THALIANA HOMEOBOX GENE1 (ATH1). Inactivation of genes in this module fully rescues pny pnf defects. We further show that BOP1 directly activates ATH1, whereas activation of KNAT6 is indirect. The pny pnf restoration correlates with renewed accumulation of transcripts conferring floral meristem identity, including FD, SQUAMOSA PROMOTER-BINDING PROTEIN LIKE genes, LEAFY, and APETALA1. To gain insight into how this module blocks flowering, we analyzed the transcriptome of BOP1-overexpressing plants. Our data suggest a central role for the microRNA156-SQUAMOSA PROMOTER BINDING PROTEIN-LIKE-microRNA172 module in integrating stress signals conferred in part by promotion of jasmonic acid biosynthesis. These data reveal a potential mechanism by which repression of lateral organ boundary genes by PNY-PNF is essential for flowering. PMID:26417006

  11. Identification of the arabidopsis RAM/MOR signalling network: adding new regulatory players in plant stem cell maintenance and cell polarization

    PubMed Central

    Zermiani, Monica; Begheldo, Maura; Nonis, Alessandro; Palme, Klaus; Mizzi, Luca; Morandini, Piero; Nonis, Alberto; Ruperti, Benedetto

    2015-01-01

    Background and Aims The RAM/MOR signalling network of eukaryotes is a conserved regulatory module involved in co-ordination of stem cell maintenance, cell differentiation and polarity establishment. To date, no such signalling network has been identified in plants. Methods Genes encoding the bona fide core components of the RAM/MOR pathway were identified in Arabidopsis thaliana (arabidopsis) by sequence similarity searches conducted with the known components from other species. The transcriptional network(s) of the arabidopsis RAM/MOR signalling pathway were identified by running in-depth in silico analyses for genes co-regulated with the core components. In situ hybridization was used to confirm tissue-specific expression of selected RAM/MOR genes. Key Results Co-expression data suggested that the arabidopsis RAM/MOR pathway may include genes involved in floral transition, by co-operating with chromatin remodelling and mRNA processing/post-transcriptional gene silencing factors, and genes involved in the regulation of pollen tube polar growth. The RAM/MOR pathway may act upstream of the ROP1 machinery, affecting pollen tube polar growth, based on the co-expression of its components with ROP-GEFs. In silico tissue-specific co-expression data and in situ hybridization experiments suggest that different components of the arabidopsis RAM/MOR are expressed in the shoot apical meristem and inflorescence meristem and may be involved in the fine-tuning of stem cell maintenance and cell differentiation. Conclusions The arabidopsis RAM/MOR pathway may be part of the signalling cascade that converges in pollen tube polarized growth and in fine-tuning stem cell maintenance, differentiation and organ polarity. PMID:26078466

  12. Surveillance and maintenance report on the Alpha-4 Building at the Oak Ridge Y-12 Plant for fiscal year 1995

    SciTech Connect

    Sollenberger, M.L.; Sparkman, D.E.; Reynolds, R.M.

    1995-12-01

    Part of the Environmental Restoration Division and funded by the Office of Environmental Management (EM-40) Program, the Oak Ridge Y-l2 Plant Decontamination and Decommissioning Program strives to protect human health and the environment and reduce the number of hazardous-material-contaminated facilities by properly managing and dispositioning facilities when they are no longer required to fulfill a site mission. Building 9201-4, known as Alpha-4, is the only facility at the Y-12 Plant under the D and D Program, and it is the D and D Program that provides surveillance and maintenance (S and M) of the facility. Alpha-4 housed uranium enrichment operations from 1945--47. In 1955 a process known as Colex, for column exchange, that involved electrochemical and solvent extraction processes began. These processes required substantial quantities of mercury as a solvent to separate lithium-6 from lithium-7 (in the form of lithium hydroxide). The Colex process was discontinued in 1962, leaving a legacy of process equipment and lines contaminated with mercury and lithium hydroxide. Now in the inactive-shutdown phase, Alpha-4 requires an S and M program that provides for risk mitigation, hazard abatement, and site preparation for subsequent D and D and/or long-term maintenance of the shutdown status of the building. Daily surveillance activities emphasizes structural integrity, leak detection, safeguards, health of personnel, environmental issues, safety conditions, equipment, hazardous materials, mercury monitoring, and cleanup. This report communicates the status of the program plans and specific surveillance and maintenance requirements for Alpha-4.

  13. Construction and Maintenance of the Optimal Photosynthetic Systems of the Leaf, Herbaceous Plant and Tree: an Eco-developmental Treatise

    PubMed Central

    TERASHIMA, ICHIRO; ARAYA, TAKAO; MIYAZAWA, SHIN-ICHI; SONE, KOSEI; YANO, SATOSHI

    2004-01-01

    • Background and Aims The paper by Monsi and Saeki in 1953 (Japanese Journal of Botany 14: 22–52) was pioneering not only in mathematical modelling of canopy photosynthesis but also in eco-developmental studies of seasonal changes in leaf canopies. • Scope Construction and maintenance mechanisms of efficient photosynthetic systems at three different scaling levels—single leaves, herbaceous plants and trees—are reviewed mainly based on the nitrogen optimization theory. First, the nitrogen optimization theory with respect to the canopy and the single leaf is briefly introduced. Secondly, significance of leaf thickness in CO2 diffusion in the leaf and in leaf photosynthesis is discussed. Thirdly, mechanisms of adjustment of photosynthetic properties of the leaf within the herbaceous plant individual throughout its life are discussed. In particular, roles of sugar sensing, redox control and of cytokinin are highlighted. Finally, the development of a tree is considered. • Conclusions Various mechanisms contribute to construction and maintenance of efficient photosynthetic systems. Molecular backgrounds of these ecologically important mechanisms should be clarified. The construction mechanisms of the tree cannot be explained solely by the nitrogen optimization theory. It is proposed that the pipe model theory in its differential form could be a potential tool in future studies in this research area. PMID:15598701

  14. Simple plant-based design strategies for volatile organic pollutants

    SciTech Connect

    Narayanan, M.; Erickson, L.E.; Davis, L.C.

    1999-12-31

    Vegetation which enhances in-situ biodegradation of organic compounds can play a key role in the bioremediation of such contaminants in polluted soils and groundwater. Plants may act directly on some contaminants by degrading them, but their main effect is to enhance microbial populations in the thizosphere. Microbially mediated transformations are thus indirectly facilitated by root exudates which nourish the indigenous microorganisms. Plants may also be viewed as a solar driven pump-and-treat system which can contain a plume and reduce the spread of contaminated water. Laboratory investigations carried out in a growth chamber with alfalfa plants provide evidence for the (microbially mediated) biodegradation of organic compounds such as toluene, phenol and TCE. Alfalfa plants tolerate concentrations of these organics in contaminated water up to 100 mg/L. They facilitate transfer of the contaminants from the saturated to the vadose zone. For volatile organic compounds such as TCE, vegetation provides a controlled release of compounds and hence assures dilution of the TCE evapotranspired into the atmosphere from contaminated soils. Using a range of calculated plausible scenarios, it is shown that intermedia transfer caused by volatilization associated with plants is most unlikely to lead to exceedance of standards for gas phase contamination, for most volatile contaminants. Possible action level exceedances might occur with highly toxic substances including vinyl chloride and carbon tetrachloride, if they re present in ground water at levels above kilogram amounts in a single plume of a few hectares, and released by vigorously growing plants under hot dry conditions. Information needed for the calculation and design of plant-based bioremediation systems for typical sites is discussed in this paper.

  15. MATHEMATICAL MODEL OF PLANT UPTAKE AND TRANSLOCATION OF ORGANIC CHEMICALS: APPLICATION TO EXPERIMENTS

    EPA Science Inventory

    Uptake, transport, and accumulation of organic chemicals by plants are influenced by characteristics of the plant and properties of the chemical, soil, and environmental conditions. athematical model for uptake of organic chemicals by plants was calibrated by application to data ...

  16. EVALUATION OF OPERATION AND MAINTENANCE FACTORS LIMITING MUNICIPAL WASTEWATER TREATMENT PLANT PERFORMANCE. PHASE II

    EPA Science Inventory

    Many of the country's wastewater treatment plants do not meet design expectations and NPDES permit standards. A research project was initiated to identify, quantify and rank the causes of this poor performance by comprehensive evaluations of 50 plants in nine western states. The ...

  17. 10 CFR 50.65 - Requirements for monitoring the effectiveness of maintenance at nuclear power plants.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... LICENSING OF PRODUCTION AND UTILIZATION FACILITIES Issuance, Limitations, and Conditions of Licenses and... plants. The requirements of this section are applicable during all conditions of plant operation, including normal shutdown operations. (a)(1) Each holder of an operating license for a nuclear power...

  18. The Use of Medicinal Plants by Migrant People: Adaptation, Maintenance, and Replacement

    PubMed Central

    de Medeiros, Patrícia Muniz; Soldati, Gustavo Taboada; Alencar, Nélson Leal; Vandebroek, Ina; Pieroni, Andrea; Hanazaki, Natalia; de Albuquerque, Ulysses Paulino

    2012-01-01

    Given the importance of studying the knowledge, beliefs, and practices of migrant communities to understand the dynamics of plant resource use, we reviewed the scientific literature concerning the use of medicinal plants by migrant populations engaged in international or long-distance migrations. We considered the importance of two processes: (1) adaptation to the new flora of the host country (i.e., substitution and incorporation of plants in the pharmacopoeia) and (2) continued use and acquisition of the original flora from migrants' home countries (i.e., importation, cultivation, and/or continued use of plants that grow in both host and home environments). We suggest that, depending on the specific context and conditions of migration, different processes that determine the use and/or selection of plants as herbal medicines may become predominant. PMID:22110548

  19. Structural Dynamic and Desiccation Damage in Plant reproductive Organs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant reproductive structures provide ideal systems to study the impact of water loss on cellular systems. Diverse physiologies in related taxa or among different organs (e.g., leaves, overwintering structures, pollen and embryos) allow us to compare sensitivities among structures and identify prima...

  20. PILOT PLANT PROJECT FOR REMOVING ORGANIC SUBSTANCES FROM DRINKING WATER

    EPA Science Inventory

    This report describes research on the European practice of preozonation of water to modify naturally occurring organics, followed by bacteria activated carbon (BAC) adsorption to remove trihalomethane precursors. A 100-gal/min pilot plant was designed, constructed and operated to...

  1. Repeat-containing protein effectors of plant-associated organisms

    PubMed Central

    Mesarich, Carl H.; Bowen, Joanna K.; Hamiaux, Cyril; Templeton, Matthew D.

    2015-01-01

    Many plant-associated organisms, including microbes, nematodes, and insects, deliver effector proteins into the apoplast, vascular tissue, or cell cytoplasm of their prospective hosts. These effectors function to promote colonization, typically by altering host physiology or by modulating host immune responses. The same effectors however, can also trigger host immunity in the presence of cognate host immune receptor proteins, and thus prevent colonization. To circumvent effector-triggered immunity, or to further enhance host colonization, plant-associated organisms often rely on adaptive effector evolution. In recent years, it has become increasingly apparent that several effectors of plant-associated organisms are repeat-containing proteins (RCPs) that carry tandem or non-tandem arrays of an amino acid sequence or structural motif. In this review, we highlight the diverse roles that these repeat domains play in RCP effector function. We also draw attention to the potential role of these repeat domains in adaptive evolution with regards to RCP effector function and the evasion of effector-triggered immunity. The aim of this review is to increase the profile of RCP effectors from plant-associated organisms. PMID:26557126

  2. 7 CFR 800.148 - Maintenance and retention of records on organization, staffing, and budget.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... approved scale testing organizations shall maintain complete records of their organization. These records... records shall be maintained for 5 years. (b) Staffing. Agencies, contractors, and approved scale testing... scale testing organizations shall maintain complete records of their budget. These records consist...

  3. 7 CFR 800.148 - Maintenance and retention of records on organization, staffing, and budget.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... approved scale testing organizations shall maintain complete records of their organization. These records... records shall be maintained for 5 years. (b) Staffing. Agencies, contractors, and approved scale testing... scale testing organizations shall maintain complete records of their budget. These records consist...

  4. Intelligent user interface for expert systems applied to power plant maintenance and troubleshooting

    SciTech Connect

    Kock, C.G.; Isle, B.A.; Butler, A.W.

    1988-03-01

    A research and development project is under way to specify, design, construct, and evaluate a user interface system to meet the unique requirements of a delivery vehicle for a knowledge-based system applied to gas turbine electronics equipment maintenance and troubleshooting. The user interface is a portable device with text display, video and overlay graphics display, voice recognition and speech production, special-function keypad, and printer. A modular software structure based on a serial communications protocol between user interface device and expert system host computer provides flexibility, expandability, and a simple, effective user interface dialogue.

  5. Effective maintenance practices to manage system aging

    NASA Astrophysics Data System (ADS)

    Chockie, Alan; Bjorkelo, Kenneth

    A study for the Nuclear Regulatory Commission was recently undertaken to identify effective maintenance practices that could be adapted by the nuclear industry in the United States to assist in managing the aging degradation of plant systems and components. Four organizations were examined to assess the influence of maintenance programs on addressing the system and component aging degradation issues. An effective maintenance program was found to be essential to the management of system and component aging. Four key elements of an effective maintenance program that are important to an aging management were identified: (1) the selection of critical systems and components; (2) the development of an understanding of aging through the collection and analysis of equipment performance information; (3) the development of appropriate preventive and predictive maintenance tasks to manage equipment and system aging degradation; and (4) the use of feedback mechanisms to continuously improve the management of aging systems and components. These elements were found to be common to all four organizations.

  6. Pollution prevention opportunity assessment for the Maintenance Engineering Department (Organization 8513).

    SciTech Connect

    Richardson, Anastasia Dawn

    2003-04-01

    This Pollution Prevention Opportunity Assessment (PPOA) was conducted for the Maintenance Engineering Department (85 13) in September and October of 2002. The primary purpose of this PPOA is to provide recommendations to assist 8513 in reducing the generation of waste and increasing the purchase of environmentally preferable products. This report contains a summary of the information collected, the analyses performed, and recommended options for implementation. The Sandia National Laboratories/New Mexico Pollution Prevention Group will continue to work with 8513 to implement the recommendations.

  7. Immunoglobulin-domain proteins required for maintenance of ventral nerve cord organization.

    PubMed

    Aurelio, Oscar; Hall, David H; Hobert, Oliver

    2002-01-25

    During development, neurons extend axons along defined routes to specific target cells. We show that additional mechanisms ensure that axons maintain their correct positioning in defined axonal tracts. After termination of axonal outgrowth and target recognition, axons in the ventral nerve cord (VNC) of Caenorhabditis elegans require the presence of a specific VNC neuron, PVT, to maintain their correct positioning in the left and right fascicles of the VNC. PVT may exert its stabilizing function by the temporally tightly controlled secretion of 2-immunoglobulin (Ig)-domain proteins encoded by the zig genes. Dedicated axon maintenance mechanisms may be widely used to ensure the preservation of functional neuronal circuitries. PMID:11809975

  8. Stochastic models for plant microtubule self-organization and structure.

    PubMed

    Eren, Ezgi C; Dixit, Ram; Gautam, Natarajan

    2015-12-01

    One of the key enablers of shape and growth in plant cells is the cortical microtubule (CMT) system, which is a polymer array that forms an appropriately-structured scaffolding in each cell. Plant biologists have shown that stochastic dynamics and simple rules of interactions between CMTs can lead to a coaligned CMT array structure. However, the mechanisms and conditions that cause CMT arrays to become organized are not well understood. It is prohibitively time-consuming to use actual plants to study the effect of various genetic mutations and environmental conditions on CMT self-organization. In fact, even computer simulations with multiple replications are not fast enough due to the spatio-temporal complexity of the system. To redress this shortcoming, we develop analytical models and methods for expeditiously computing CMT system metrics that are related to self-organization and array structure. In particular, we formulate a mean-field model to derive sufficient conditions for the organization to occur. We show that growth-prone dynamics itself is sufficient to lead to organization in presence of interactions in the system. In addition, for such systems, we develop predictive methods for estimation of system metrics such as expected average length and number of CMTs over time, using a stochastic fluid-flow model, transient analysis, and approximation algorithms tailored to our problem. We illustrate the effectiveness of our approach through numerical test instances and discuss biological insights. PMID:25700800

  9. Hierarchical organization of a Sardinian sand dune plant community.

    PubMed

    Cusseddu, Valentina; Ceccherelli, Giulia; Bertness, Mark

    2016-01-01

    Coastal sand dunes have attracted the attention of plant ecologists for over a century, but they have largely relied on correlations to explain dune plant community organization. We examined long-standing hypotheses experimentally that sand binding, inter-specific interactions, abiotic factors and seedling recruitment are drivers of sand dune plant community structure in Sardinia, Italy. Removing foundation species from the fore-, middle- and back-dune habitats over three years led to erosion and habitat loss on the fore-dune and limited plant recovery that increased with dune elevation. Reciprocal species removals in all zones suggested that inter-specific competition is common, but that dominance is transient, particularly due to sand burial disturbance in the middle-dune. A fully factorial 2-year manipulation of water, nutrient availability and substrate stability revealed no significant proximate response to these physical factors in any dune zone. In the fore- and middle-dune, plant seeds are trapped under adult plants during seed germination, and seedling survivorship and growth generally increase with dune height in spite of increased herbivory in the back-dune. Sand and seed erosion leads to limited seed recruitment on the fore-dune while high summer temperatures and preemption of space lead to competitive dominance of woody plants in the back-dune. Our results suggest that Sardinian sand dune plant communities are organized hierarchically, structured by sand binding foundation species on the fore-dune, sand burial in the middle-dune and increasingly successful seedling recruitment, growth and competitive dominance in the back-dune. PMID:27478701

  10. Hierarchical organization of a Sardinian sand dune plant community

    PubMed Central

    Ceccherelli, Giulia; Bertness, Mark

    2016-01-01

    Coastal sand dunes have attracted the attention of plant ecologists for over a century, but they have largely relied on correlations to explain dune plant community organization. We examined long-standing hypotheses experimentally that sand binding, inter-specific interactions, abiotic factors and seedling recruitment are drivers of sand dune plant community structure in Sardinia, Italy. Removing foundation species from the fore-, middle- and back-dune habitats over three years led to erosion and habitat loss on the fore-dune and limited plant recovery that increased with dune elevation. Reciprocal species removals in all zones suggested that inter-specific competition is common, but that dominance is transient, particularly due to sand burial disturbance in the middle-dune. A fully factorial 2-year manipulation of water, nutrient availability and substrate stability revealed no significant proximate response to these physical factors in any dune zone. In the fore- and middle-dune, plant seeds are trapped under adult plants during seed germination, and seedling survivorship and growth generally increase with dune height in spite of increased herbivory in the back-dune. Sand and seed erosion leads to limited seed recruitment on the fore-dune while high summer temperatures and preemption of space lead to competitive dominance of woody plants in the back-dune. Our results suggest that Sardinian sand dune plant communities are organized hierarchically, structured by sand binding foundation species on the fore-dune, sand burial in the middle-dune and increasingly successful seedling recruitment, growth and competitive dominance in the back-dune. PMID:27478701

  11. Methods in plant foliar volatile organic compounds research1

    PubMed Central

    Materić, Dušan; Bruhn, Dan; Turner, Claire; Morgan, Geraint; Mason, Nigel; Gauci, Vincent

    2015-01-01

    Plants are a major atmospheric source of volatile organic compounds (VOCs). These secondary metabolic products protect plants from high-temperature stress, mediate in plant–plant and plant–insect communication, and affect our climate globally. The main challenges in plant foliar VOC research are accurate sampling, the inherent reactivity of some VOC compounds that makes them hard to detect directly, and their low concentrations. Plant VOC research relies on analytical techniques for trace gas analysis, usually based on gas chromatography and soft chemical ionization mass spectrometry. Until now, these techniques (especially the latter one) have been developed and used primarily by physicists and analytical scientists, who have used them in a wide range of scientific research areas (e.g., aroma, disease biomarkers, hazardous compound detection, atmospheric chemistry). The interdisciplinary nature of plant foliar VOC research has recently attracted the attention of biologists, bringing them into the field of applied environmental analytical sciences. In this paper, we review the sampling methods and available analytical techniques used in plant foliar VOC research to provide a comprehensive resource that will allow biologists moving into the field to choose the most appropriate approach for their studies. PMID:26697273

  12. Defer Maintenance, Invite Disaster

    ERIC Educational Resources Information Center

    Bowman, William W.

    1977-01-01

    An AGB- and NACUBO-sponsored survey showed that "wish lists" are accumulating overdue major maintenance projects because energy costs are consuming physical plant budgets. Problem areas are discussed: budget "guesstimation," preventive maintenance, deferred maintenance inventory, the APPA accounting format, resource allocation, and inflation.…

  13. Reliability and maintenance in European nuclear power plants: A structural analysis of a controlled stochastic process

    SciTech Connect

    Sturm, R.

    1991-01-01

    Two aspects of performance are of main concern: plant availability and plant reliability (defined as the conditional probability of an unplanned shutdown). The goal of the research is a unified framework that combines behavioral models of optimizing agents with models of complex technical systems that take into account the dynamic and stochastic features of the system. In order to achieve this synthesis, two liens of work are necessary. One line requires a deeper understanding of complex production systems and the type of data they give rise to; the other line involves the specification and estimation of a rigorously specified behavioral model. Plant operations are modeled as a controlled stochastic process, and the sequence of up and downtime spells is analyzed during failure time and point process models. Similar to work on rational expectations and structural econometric models, the behavior model of how the plant process is controlled is formulated at the level of basic processes, i.e., the objective function of the plant manager, technical constraints, and stochastic disturbances.

  14. Tubulin tyrosine nitration regulates microtubule organization in plant cells

    PubMed Central

    Blume, Yaroslav B.; Krasylenko, Yuliya A.; Demchuk, Oleh M.; Yemets, Alla I.

    2013-01-01

    During last years, selective tyrosine nitration of plant proteins gains importance as well-recognized pathway of direct nitric oxide (NO) signal transduction. Plant microtubules are one of the intracellular signaling targets for NO, however, the molecular mechanisms of NO signal transduction with the involvement of cytoskeletal proteins remain to be elucidated. Since biochemical evidence of plant α-tubulin tyrosine nitration has been obtained recently, potential role of this posttranslational modification in regulation of microtubules organization in plant cell is estimated in current paper. It was shown that 3-nitrotyrosine (3-NO2-Tyr) induced partially reversible Arabidopsis primary root growth inhibition, alterations of root hairs morphology and organization of microtubules in root cells. It was also revealed that 3-NO2-Tyr intensively decorates such highly dynamic microtubular arrays as preprophase bands, mitotic spindles and phragmoplasts of Nicotiana tabacum Bright Yellow-2 (BY-2) cells under physiological conditions. Moreover, 3D models of the mitotic kinesin-8 complexes with the tail of detyrosinated, tyrosinated and tyrosine nitrated α-tubulin (on C-terminal Tyr 450 residue) from Arabidopsis were reconstructed in silico to investigate the potential influence of tubulin nitrotyrosination on the molecular dynamics of α-tubulin and kinesin-8 interaction. Generally, presented data suggest that plant α-tubulin tyrosine nitration can be considered as its common posttranslational modification, the direct mechanism of NO signal transduction with the participation of microtubules under physiological conditions and one of the hallmarks of the increased microtubule dynamics. PMID:24421781

  15. Experience with organic Rankine cycles in heat recovery power plants

    SciTech Connect

    Bronicki, L.Y.; Elovic, A.; Rettger, P.

    1996-11-01

    Over the last 30 years, organic Rankine cycles (ORC) have been increasingly employed to produce power from various heat sources when other alternatives were either technically not feasible or economical. These power plants have logged a total of over 100 million turbine hours of experience demonstrating the maturity and field proven technology of the ORC cycle. The cycle is well adapted to low to moderate temperature heat sources such as waste heat from industrial plants and is widely used to recover energy from geothermal resources. The above cycle technology is well established and applicable to heat recovery of medium size gas turbines and offers significant advantages over conventional steam bottoming cycles.

  16. Water management requirements for animal and plant maintenance on the Space Station

    NASA Technical Reports Server (NTRS)

    Johnson, C. C.; Rasmussen, D.; Curran, G.

    1987-01-01

    Long-duration Space Station experiments that use animals and plants as test specimens will require increased automation and advanced technologies for water management in order to free scientist-astronauts from routine but time-consuming housekeeping tasks. The three areas that have been identified as requiring water management and that are discusseed are: (1) drinking water and humidity condensate of the animals, (2) nutrient solution and transpired water of the plants, and (3) habitat cleaning methods. Automation potential, technology assessment, crew time savings, and resupply penalties are also discussed.

  17. Identification of the impacts of maintenance and testing upon the safety of LWR power plants. Final report

    SciTech Connect

    Husseiny, A. A.; Sabri, Z. A.; Turnage, J. J.

    1980-04-01

    The present study was designed to identify the impact of maintenance and testing (M and T) upon the safety of LWR power plants. The study involved data extraction from various sources reporting safety-related and operation-related nuclear power plant experience. Primary sources reviewed, including Licensee Event Reports (LER's) submitted to the NRC, revealed that only ten percent of events reported could be identified as M and T problems. The collected data were collated in a manner that would allow identification of principal types of problems which are associated with the performance of M and T tasks in LWR power plants. Frequencies of occurrence of events and their general endemic nature were analyzed using data clustering and pattern recognition techniques, as well as chi-square analyses for sparse contingency tables. The results of these analyses identified seven major categories of M and T error modes which were related to individual facilities and reactor type. Data review indicated that few M and T problems were directly related to procedural inadequacies, with the majority of events being attributable to human error.

  18. 76 FR 65753 - Monitoring the Effectiveness of Maintenance at Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-24

    ... Commission. ACTION: Draft regulatory guide; extension of comment period. SUMMARY: On September 6, 2011 (76 FR..., 2011 (76 FR 55137), the NRC published a notice of issuance and availability of DG-1278. By e-mail dated... Plants,'' of Title 10 of the Code of Federal Regulations, part 50, ``Domestic Licensing of Production...

  19. Joint application of AI techniques, PRA and disturbance analysis methodology to problems in the maintenance and design of nuclear power plants. Final report

    SciTech Connect

    Okrent, D.

    1989-03-01

    This final report summarizes the accomplishments of a two year research project entitled ``Joint Application of Artificial Intelligence Techniques, Probabilistic Risk Analysis, and Disturbance Analysis Methodology to Problems in the Maintenance and Design of Nuclear Power Plants. The objective of this project is to develop and apply appropriate combinations of techniques from artificial intelligence, (AI), reliability and risk analysis and disturbance analysis to well-defined programmatic problems of nuclear power plants. Reactor operations issues were added to those of design and maintenance as the project progressed.

  20. Joint application of AI techniques, PRA and disturbance analysis methodology to problems in the maintenance and design of nuclear power plants

    SciTech Connect

    Okrent, D.

    1989-03-01

    This final report summarizes the accomplishments of a two year research project entitled Joint Application of Artificial Intelligence Techniques, Probabilistic Risk Analysis, and Disturbance Analysis Methodology to Problems in the Maintenance and Design of Nuclear Power Plants. The objective of this project is to develop and apply appropriate combinations of techniques from artificial intelligence, (AI), reliability and risk analysis and disturbance analysis to well-defined programmatic problems of nuclear power plants. Reactor operations issues were added to those of design and maintenance as the project progressed.

  1. Demonstration of reliability centered maintenance

    SciTech Connect

    Schwan, C.A.; Morgan, T.A. )

    1991-04-01

    Reliability centered maintenance (RCM) is an approach to preventive maintenance planning and evaluation that has been used successfully by other industries, most notably the airlines and military. Now EPRI is demonstrating RCM in the commercial nuclear power industry. Just completed are large-scale, two-year demonstrations at Rochester Gas Electric (Ginna Nuclear Power Station) and Southern California Edison (San Onofre Nuclear Generating Station). Both demonstrations were begun in the spring of 1988. At each plant, RCM was performed on 12 to 21 major systems. Both demonstrations determined that RCM is an appropriate means to optimize a PM program and improve nuclear plant preventive maintenance on a large scale. Such favorable results had been suggested by three earlier EPRI pilot studies at Florida Power Light, Duke Power, and Southern California Edison. EPRI selected the Ginna and San Onofre sites because, together, they represent a broad range of utility and plant size, plant organization, plant age, and histories of availability and reliability. Significant steps in each demonstration included: selecting and prioritizing plant systems for RCM evaluation; performing the RCM evaluation steps on selected systems; evaluating the RCM recommendations by a multi-disciplinary task force; implementing the RCM recommendations; establishing a system to track and verify the RCM benefits; and establishing procedures to update the RCM bases and recommendations with time (a living program). 7 refs., 1 tab.

  2. Do plants reflect atmospheric concentrations of persistent organic contaminants?

    SciTech Connect

    Jones, K.C.

    1994-12-31

    Chemical analysis of several types of plants -- such as pine needles, lichens, mosses and grasses -- has been used by numerous workers as a means of inferring spatial and temporal variations in the atmospheric concentrations of persistent organic compounds (e.g. PCBs, PAHs, CBs and PCDD/Fs). This is usually because plants are perceived as convenient `passive` air samplers and assumed to `integrate` variations in ambient concentrations during their lifetime. More recently, various researchers have sought to understand the mechanisms of exchange/uptake at the air vegetation surface, with a view to refining the use of vegetation sampling techniques and understanding the role of vegetation in influencing the global cycling of these compounds. This presentation will review some of the recent advances in this area, highlighting some of pitfalls and beneficial uses of employing plants as `monitoring tools`.

  3. Importance Of Thermography For Preventive Maintenance And Energy Conservation In Industrial Plants

    NASA Astrophysics Data System (ADS)

    Loch, Alan A.

    1982-03-01

    Thermography, currently being applied by utilizing the AGA 750, 720 and 782, has demonstrated its value as a maintenance and conservation tool. It is efficient because in the scanner's portable configuration, hand held or car hood mounted, large quantities of electrical equipment, square footage of thermal envelope, steam distribution piping, etc., can be covered. The severity of the problem can be estimated easily by measuring the object's temperature and cataloged for future action by quickly recording the situation with a photograph. It is a productive procedure which identifies problems which justify the cost of the survey in roughly 70% of the cases. Moreover, the problems located by the thermographic survey are usually corrected. This is because of the high impact of the polaroid pictures taken during the survey. The technicians correcting the problem, the engineering department, and the senior management personnel can all understand the situation because of the clarity of the photograph. Furthermore, feedback concerning the repairs can be easily obtained by rescanning the problems involved.

  4. Assisting gay men to maintain safer sex: an evaluation of an AIDS service organization's safer sex maintenance program.

    PubMed

    Miller, R L

    1995-01-01

    As the second decade of the AIDS crisis unfolds, increasing concern has been raised that the widespread adoption of condom use that occurred among gay men in the 1980s is not being maintained. Most interventions to promote condom use among gay men are delivered by community-based organizations via programs that are virtually undocumented; little is known about their effectiveness, or the processes by which they may work. This study describes safer sex practices among self-identified gay men following their participation in an intervention developed and implemented by a community-based organization. The intervention was designed to enhance men's attitudes, beliefs, and self-efficacy expectations to maintain safer sex. Among 150 men with complete data at both assessments, self-reported condom use was low. Men reported using condoms more consistently for anal sexual behavior than oral sexual behavior, but there were men who reported consistent unprotected anal sexual intercourse. The intervention had little impact on patterns of behavior over time, although desired changes in attitudes, beliefs, and self-efficacy expectations were evidenced following the intervention. The results suggest the importance of assisting community-based organizations to document program models. Findings also suggest that community-based organizations can develop interventions to successfully enhance factors that theoretically support maintenance of safer sexual behaviors. PMID:8664098

  5. Transcriptional Switches Direct Plant Organ Formation and Patterning

    PubMed Central

    Moreno-Risueno, Miguel A.; Van Norman, Jaimie M.; Benfey, Philip N.

    2013-01-01

    Development of multicellular organisms requires specification of diverse cell types. In plants, development is continuous and because plant cells are surrounded by rigid cell walls, cell division and specification of daughter cell fate must be carefully orchestrated. During embryonic and postembryonic plant development, the specification of cell types is determined both by positional cues and cell lineage. The establishment of distinct transcriptional domains is a fundamental mechanism for determining different cell fates. In this review, we focus on four examples from recent literature of switches operating in cell fate decisions that are regulated by transcriptional mechanisms. First, we highlight a transcriptional mechanism involving a mobile transcription factor in formation of the two ground tissue cell types in roots. Specification of vascular cell types is then discussed, including new details about xylem cell-type specification via a mobile microRNA. Next, transcriptional regulation of two key embryonic developmental events is considered: establishment of apical–basal polarity in the single-celled zygote and specification of distinct root and shoot stem cell populations in the plant embryo. Finally, a dynamic transcriptional mechanism for lateral organ positioning that integrates spatial and temporal information into a repeating pattern is summarized. PMID:22305165

  6. Arabidopsis ECERIFERUM9 involvement in cuticle formation and maintenance of plant water status.

    PubMed

    Lü, Shiyou; Zhao, Huayan; Des Marais, David L; Parsons, Eugene P; Wen, Xiaoxue; Xu, Xiaojing; Bangarusamy, Dhinoth K; Wang, Guangchao; Rowland, Owen; Juenger, Thomas; Bressan, Ray A; Jenks, Matthew A

    2012-07-01

    Mutation of the ECERIFERUM9 (CER9) gene in Arabidopsis (Arabidopsis thaliana) causes elevated amounts of 18-carbon-length cutin monomers and a dramatic shift in the cuticular wax profile (especially on leaves) toward the very-long-chain free fatty acids tetracosanoic acid (C₂₄) and hexacosanoic acid (C₂₆). Relative to the wild type, cer9 mutants exhibit elevated cuticle membrane thickness over epidermal cells and cuticular ledges with increased occlusion of the stomatal pore. The cuticular phenotypes of cer9 are associated with delayed onset of wilting in plants experiencing water deficit, lower transpiration rates, and improved water use efficiency measured as carbon isotope discrimination. The CER9 protein thus encodes a novel determinant of plant drought tolerance-associated traits, one whose deficiency elevates cutin synthesis, redistributes wax composition, and suppresses transpiration. Map-based cloning identified CER9, and sequence analysis predicted that it encodes an E3 ubiquitin ligase homologous to yeast Doa10 (previously shown to target endoplasmic reticulum proteins for proteasomal degradation). To further elucidate CER9 function, the impact of CER9 deficiency on interactions with other genes was examined using double mutant and transcriptome analyses. For both wax and cutin, cer9 showed mostly additive effects with cer6, long-chain acyl-CoA synthetase1 (lacs1), and lacs2 and revealed its role in early steps of both wax and cutin synthetic pathways. Transcriptome analysis revealed that the cer9 mutation affected diverse cellular processes, with primary impact on genes associated with diverse stress responses. The discovery of CER9 lays new groundwork for developing novel cuticle-based strategies for improving the drought tolerance and water use efficiency of crop plants. PMID:22635115

  7. EVALUATION OF INNOVATIVE LOW-VOLATILE ORGANIC COMPOUND (VOC) INDUSTRIAL MAINTENANCE (IM) COATINGS

    EPA Science Inventory

    The paper discusses a field evaluation of the feasibility of using alternative low-volatile organic compound (VOC) coatings to replace higher-VOC coatings. he evaluation includes chemical, performance, and outdoor exposure testing. he feasibility of five alternative coatings for ...

  8. Simulated impacts of crop residue removal and tillage on soil organic matter maintenance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cellulosic biofuel production may generate new markets and additional revenue for farmers. However, residue removal may cause other environmental problems such as soil erosion and loss of soil organic matter (SOM). The objective of this study was to determine the amounts of residue necessary for SOM...

  9. Strategic relatedness in mergers and financial performance: the case of the health maintenance organization industry in the United States.

    PubMed

    Weech-Maldonado, Robert

    2002-11-01

    Knowledge and identification of strategic factors associated with favourable post-acquisition performance can be of benefit to both managers and shareholders. From a management perspective, the identification of contextual factors that can influence postmerger performance is 'strategic' in nature, and should be considered in the analysis of future acquisitions. Within the context of the health maintenance organization (HMO) industry, this study examines the impact of strategic relatedness on postmerger financial performance. Strategic relatedness is conceptualized as similarity between the acquirer and target HMOs in terms of operational efficiency, marketing orientation, organizational structure and profit orientation. Regression analysis showed that similarity in operational efficiency and similarity in HMO structure were associated with better postmerger financial performance. However, marketing orientation similarity and profit orientation similarity were not significantly related to postmerger performance. This finding suggests that HMO mergers involving firms with similar strategic orientations and similar approaches to the delivery of care have greater strategic fit and experience better financial performance. PMID:12396551

  10. Cryogenics maintenance strategy

    NASA Astrophysics Data System (ADS)

    Cruzat, Fabiola

    2012-09-01

    ALMA is an interferometer composed of 66 independent systems, with specific maintenance requirements for each subsystem. To optimize the observation time and reduce downtime maintenance, requirements are very demanding. One subsystem with high maintenance efforts is cryogenics and vacuum. To organize the maintenance, the Cryogenic and Vacuum department is using and implementing different tools. These are monitoring and problem reporting systems and CMMS. This leads to different maintenance approaches: Preventive Maintenance, Corrective Maintenance and Condition Based Maintenance. In order to coordinate activities with other departments the preventive maintenance schedule is kept as flexible as systems allow. To cope with unavoidable failures, the team has to be prepared to work under any condition with the spares on time. Computerized maintenance management system (CMMS) will help to manage inventory control for reliable spare part handling, the correct record of work orders and traceability of maintenance activities. For an optimized approach the department is currently evaluating where preventive or condition based maintenance applies to comply with the individual system demand. Considering the change from maintenance contracts to in-house maintenance will help to minimize costs and increase availability of parts. Due to increased number of system and tasks the cryo team needs to grow. Training of all staff members is mandatory, in depth knowledge must be built up by doing complex maintenance activities in the Cryo group, use of advanced computerized metrology systems.

  11. The importance of aboveground–belowground interactions on the evolution and maintenance of variation in plant defense traits

    PubMed Central

    van Geem, Moniek; Gols, Rieta; van Dam, Nicole M.; van der Putten, Wim H.; Fortuna, Taiadjana; Harvey, Jeffrey A.

    2013-01-01

    Over the past two decades a growing body of empirical research has shown that many ecological processes are mediated by a complex array of indirect interactions occurring between rhizosphere-inhabiting organisms and those found on aboveground plant parts. Aboveground–belowground studies have thus far focused on elucidating processes and underlying mechanisms that mediate the behavior and performance of invertebrates in opposite ecosystem compartments. Less is known about genetic variation in plant traits such as defense as that may be driven by above- and belowground trophic interactions. For instance, although our understanding of genetic variation in aboveground plant traits and its effects on community-level interactions is well developed, little is known about the importance of aboveground–belowground interactions in driving this variation. Plant traits may have evolved in response to selection pressures from above- and below-ground interactions from antagonists and mutualists. Here, we discuss gaps in our understanding of genetic variation in plant-related traits as they relate to aboveground and belowground multitrophic interactions. When metabolic resources are limiting, multiple attacks by antagonists in both domains may lead to trade-offs. In nature, these trade-offs may critically depend upon their effects on plant fitness. Natural enemies of herbivores may also influence selection for different traits via top–down control. At larger scales these interactions may generate evolutionary “hotspots” where the expression of various plant traits is the result of strong reciprocal selection via direct and indirect interactions. The role of abiotic factors in driving genetic variation in plant traits is also discussed. PMID:24348484

  12. Kerman Photovoltaic Power Plant R&D data collection computer system operations and maintenance

    SciTech Connect

    Rosen, P.B.

    1994-06-01

    The Supervisory Control and Data Acquisition (SCADA) system at the Kerman PV Plant monitors 52 analog, 44 status, 13 control, and 4 accumulator data points in real-time. A Remote Terminal Unit (RTU) polls 7 peripheral data acquisition units that are distributed throughout the plant once every second, and stores all analog, status, and accumulator points that have changed since the last scan. The R&D Computer, which is connected to the SCADA RTU via a RS-232 serial link, polls the RTU once every 5-7 seconds and records any values that have changed since the last scan. A SCADA software package called RealFlex runs on the R&D computer and stores all updated data values taken from the RTU, along with a time-stamp for each, in a historical real-time database. From this database, averages of all analog data points and snapshots of all status points are generated every 10 minutes and appended to a daily file. These files are downloaded via modem by PVUSA/Davis staff every day, and the data is placed into the PVUSA database.

  13. Does natural selection organize ecosystems for the maintenance of high productivity and diversity?

    PubMed Central

    Leigh, Egbert Giles; Vermeij, Geerat Jacobus

    2002-01-01

    Three types of evidence suggest that natural ecosystems are organized for high productivity and diversity: (i) changes not previously experienced by a natural ecosystem, such as novel human disturbances, tend to diminish its productivity and/or diversity, just as 'random' changes in a machine designed for a function usually impair its execution of that function; (ii) humans strive to recreate properties of natural ecosystems to enhance productivity of artificial ones, as farmers try to recreate properties of natural soils in their fields; and (iii) productivity and diversity have increased during the Earth's history as a whole, and after every major biotic crisis. Natural selection results in ecosystems organized to maintain high productivity of organic matter and diversity of species, just as competition among individuals in Adam Smith's ideal economy favours high production of wealth and diversity of occupations. In nature, poorly exploited energy attracts more efficient users. This circumstance favours the opening of new ways of life and more efficient recycling of resources, and eliminates most productivity-reducing 'ecological monopolies'. Ecological dominants tend to be replaced by successors with higher metabolism, which respond to more stimuli and engage in more varied interactions. Finally, increasingly efficient predators and herbivores favour faster turnover of resources. PMID:12079531

  14. Atmospheric fluidized bed combustion (AFBC) plants: an operations and maintenance study

    SciTech Connect

    Jack A. Fuller; Harvie Beavers; Robert Bessette

    2006-06-15

    The authors analyzed data from a fluidized bed boiler survey distributed during the spring of 2003 to develop appropriate AFBC (Atmospheric Fluidized Bed Combustion) performance benchmarks. The survey was sent to members of CIBO (Council of Industrial Boiler Owners), who sponsored the survey, as well as to other firms who had an operating AFBC boiler on-site. There were three primary purposes for the collection and analysis of the data contained in this fluidized bed boiler survey: (1) To develop AFBC benchmarks on technical, cost, revenue, and environmental issues; (2) to inform AFBC owners and operators of contemporary concerns and issues in the industry; (3) to improve decision making in the industry with respect to current and future plant start-ups and ongoing operations.

  15. Plant Maintenance and Improvement Experiences for Control System in UCN 5 and 6

    SciTech Connect

    Choi, D.R.; Lee, K.B.; Kim, C.J.; Chung, Y.M.

    2006-07-01

    The Plant Control System (PCS) in Korean Standard Nuclear Power Plant (KSNP) is designed to perform data acquisition and transfer function via communication data links to control most of the field components such as pumps, fans, valves, dampers and circuit breakers. The PCS installed at UCN 5 and 6 for both safety related and non -safety related functions is microprocessor based system supplied by HF Controls. Safety related functions are provided by redundant trains of microprocessor based single loop controllers with direct connections to the field input/output instruments but non-safety related functions utilize a similar construction with the input/output boards to be remotely located in cabinet arrangements near the field components. Whatever the functions, the signals to control and monitor field devices are processed through communication master (CM), HFC distributed control system, which uses Multibus I back-plane design to accommodate the requirement of multiple processors. The complex programmable logic device (CPLD) mounted on the A233 back-plane of the CM controls the processors for an adequate access to the bus so that 16 microprocessor based circuitries acting as bus masters share the public memory properly through the common bus. The bus occupation of each processor should not affect overall system response time to keep appropriate system performance. This paper discusses the comparison evaluation between the difference priority techniques and hardware change on A233 back-plane to improve the communication methods, etc., as to the bus arbitration schemes of communication master(CM) applied to UCN site based on the waveform data acquired from A233 CPLD and HFC bus design specification. (authors)

  16. MATHEMATICAL MODEL OF PLANT UPTAKE AND TRANSLOCATION OF ORGANIC CHEMICALS: DEVELOPMENT OF THE MODEL

    EPA Science Inventory

    Uptake, transport, and accumulation of organic chemicals by plants are influenced by characteristics of the plant and properties of the chemical, soil, and environmental conditions. valuations of plant contamination cannot be made experimentally for the many thousands of xenobiot...

  17. Maintenance approaches and practices in selected foreign nuclear power programs and other US industries: Review and lessons learned

    SciTech Connect

    Not Available

    1990-04-01

    The Commission published a Notice of Proposed Rule-making on Maintenance of Nuclear Power Plants on November 28, 1988, spelling out NRC's expectations in maintenance. In preparing the proposed rule, the NRC reviewed maintenance practices in other countries and considered maintenance approaches in other industries in this country. As a result of the review of maintenance practices, it was concluded that certain practices in the following areas have been found to contribute significantly to effective maintenance: (1) systems approach; (2) effectiveness monitoring; (3) technician qualifications and motivation; and (4) maintenance organization. 87 refs., 26 figs., 2 tabs.

  18. Helical growth in plant organs: mechanisms and significance.

    PubMed

    Smyth, David R

    2016-09-15

    Many plants show some form of helical growth, such as the circular searching movements of growing stems and other organs (circumnutation), tendril coiling, leaf and bud reversal (resupination), petal arrangement (contortion) and leaf blade twisting. Recent genetic findings have revealed that such helical growth may be associated with helical arrays of cortical microtubules and of overlying cellulose microfibrils. An alternative mechanism of coiling that is based on differential contraction within a bilayer has also recently been identified and underlies at least some of these growth patterns. Here, I provide an overview of the genes and cellular processes that underlie helical patterning. I also discuss the diversity of helical growth patterns in plants, highlighting their potential adaptive significance and comparing them with helical growth patterns in animals. PMID:27624832

  19. Asbestos exposure, smoking habits, and cancer incidence among production and maintenance workers in an electrochemical plant

    SciTech Connect

    Hilt, B.; Langard, S.A.; Andersen, A.; Rosenberg, J.

    1985-01-01

    The incidence of cancer was studied in a cohort of 287 men who were exposed to asbestos at a nitric acid production plant from 1928 onwards. During the observation period from 1953 through 1980 all cancer cases among the cohort members were identified in The Cancer Registry. For the whole cohort 42 cases of cancer were observed versus 30.6 expected. The figures for cancer of the lungs and pleura combined were 17 observed versus 3.7 expected. The corresponding figures for a heavily exposed subcohort were 11 observed and 1.2 expected. In that group there was also an increased incidence of colon cancer with 3 cases observed against 0.8 cases expected. Within the whole cohort four cases of pleural and one case of peritoneal malignant mesothelioma were found. There was also an increased incidence of malignant melanoma of the skin with 3 cases observed against 0.6 expected. For cancer cases that were registered as of unknown origin there were 7 cases observed and 1.4 expected. There was no increased rate ratio for cancer at any site before 20 years after the first asbestos exposure. The smoking habits of all cohort members were recorded and the relative rates for lung cancer were calculated in relation to smoking habits. In common with previous studies the results indicate a multiplicative model for the interaction between asbestos exposure and smoking in regard to lung cancer risk.

  20. Molecular Signatures of Tissue-Specific Microvascular Endothelial Cell Heterogeneity in Organ Maintenance and Regeneration

    PubMed Central

    Nolan, Daniel J.; Ginsberg, Michael; Israely, Edo; Palikuqi, Brisa; Poulos, Michael G.; James, Daylon; Ding, Bi-Sen; Schachterle, William; Liu, Ying; Rosenwaks, Zev; Butler, Jason M.; Xiang, Jenny; Rafii, Arash; Shido, Koji; Rabbany, Sina Y.; Elemento, Olivier; Rafii, Shahin

    2013-01-01

    SUMMARY Microvascular endothelial cells (ECs) within different tissues are endowed with distinct but as yet unrecognized structural, phenotypic, and functional attributes. We devised EC purification, cultivation, profiling, and transplantation models that establish tissue-specific molecular libraries of ECs devoid of lymphatic ECs or parenchymal cells. These libraries identify attributes that confer ECs with their organotypic features. We show that clusters of transcription factors, angiocrine growth factors, adhesion molecules, and chemokines are expressed in unique combinations by ECs of each organ. Furthermore, ECs respond distinctly in tissue regeneration models, hepatectomy, and myeloablation. To test the data set, we developed a transplantation model that employs generic ECs differentiated from embryonic stem cells. Transplanted generic ECs engraft into regenerating tissues and acquire features of organotypic ECs. Collectively, we demonstrate the utility of informational databases of ECs toward uncovering the extravascular and intrinsic signals that define EC heterogeneity. These factors could be exploited therapeutically to engineer tissue-specific ECs for regeneration. PMID:23871589

  1. Organ-Specific and Memory Treg Cells: Specificity, Development, Function, and Maintenance

    PubMed Central

    Gratz, Iris K.; Campbell, Daniel J.

    2014-01-01

    Foxp3+ regulatory T cells (Treg cells) are essential for establishing and maintaining self-tolerance, and also inhibit immune responses to innocuous environmental antigens. Imbalances and dysfunction in Treg cells lead to a variety of immune-mediated diseases, as deficits in Treg cell function contribute to the development autoimmune disease and pathological tissue damage, whereas overabundance of Treg cells can promote chronic infection and tumorigenesis. Recent studies have highlighted the fact that Treg cells themselves are a diverse collection of phenotypically and functionally specialized populations, with distinct developmental origins, antigen-specificities, tissue-tropisms, and homeostatic requirements. The signals directing the differentiation of these populations, their specificities and the mechanisms by which they combine to promote organ-specific and systemic tolerance, and how they embody the emerging property of regulatory memory are the focus of this review. PMID:25076948

  2. Self-organization mechanisms in the assembly and maintenance of bipolar spindles

    NASA Astrophysics Data System (ADS)

    Burbank, Kendra Stewart

    Anastral, meiotic spindles are thought to be organized differently from astral, mitotic spindles, but the field has lacked basic structural information required to describe and model them, including the location of microtubule nucleating sites and minus ends. How the various components of spindles act together to establish and maintain the dynamic bipolar structure of spindles is not understood. We measure the distributions of oriented microtubules (MTs) in metaphase anastral spindles in Xenopus extracts by fluorescence speckle microscopy and cross-correlation analysis. We localized plus ends by tubulin incorporation and combined this with the orientation data to infer the localization of minus ends. We find that minus ends are localized throughout the spindle, sparsely at the equator and at higher concentrations near the poles. This dads to the surprising conclusion that spindles contained many short MTs, not connected to the spindle poles. Based on these data, we propose a slide-and-cluster model based on four known molecular activities: MT nucleation near chromosomes, the sliding of MTs by a plus-enddirected motor, the clustering of their minus ends by a minus-end-directed motor, and the loss of MTs by dynamic instability. This work demonstrates how the interplay between two types of motors together with continual nucleation of MTs by chromosomes could organize the MTs into spindles. Our model applies to overlapping, nonkinetochore MTs in anastral spindles, and perhaps also to interpolar MTs in astral spindles. We show mathematically that the slide-and-cluster mechanism robustly forms bipolar spindles a stable steady-state length, sometimes with sharp poles. This model accounts for several experimental observations that were difficult to explain with existing models, and is the first self contained model for anastral spindle assembly, MT sliding (known as poleward flux), and spindle bistability. Our experimental results support the slide-and-cluster scenario

  3. Floral symmetry genes and the origin and maintenance of zygomorphy in a plant-pollinator mutualism.

    PubMed

    Zhang, Wenheng; Kramer, Elena M; Davis, Charles C

    2010-04-01

    The evolution of floral zygomorphy is an important innovation in flowering plants and is thought to arise principally from specialization on various insect pollinators. Floral morphology of neotropical Malpighiaceae is distinctive and highly conserved, especially with regard to symmetry, and is thought to be caused by selection by its oil-bee pollinators. We sought to characterize the genetic basis of floral zygomorphy in Malpighiaceae by investigating CYCLOIDEA2-like (CYC2-like) genes, which are required for establishing symmetry in diverse core eudicots. We identified two copies of CYC2-like genes in Malpighiaceae, which resulted from a gene duplication in the common ancestor of the family. A likely role for these loci in the development of floral zygomorphy in Malpighiaceae is demonstrated by the conserved pattern of dorsal gene expression in two distantly related neotropical species, Byrsonima crassifolia and Janusia guaranitica. Further evidence for this function is observed in a Malpighiaceae species that has moved to the paleotropics and experienced coincident shifts in pollinators, floral symmetry, and CYC2-like gene expression. The dorsal expression pat-tern observed in Malpighiaceae contrasts dramatically with their actinomorphic-flowered relatives, Centroplacaceae (Bhesa paniculata) and Elatinaceae (Bergia texana). In particular, B. texana exhibits a previously undescribed pattern of uniform CYC2 expression, suggesting that CYC2 expression among the actinomorphic ancestors of zygomorphic lineages may be much more complex than previously thought. We consider three evolutionary models that may have given rise to this patterning, including the hypothesis that floral zygomorphy in Malpighiaceae arose earlier than standard morphology-based character reconstructions suggest. PMID:20363959

  4. Floral symmetry genes and the origin and maintenance of zygomorphy in a plant-pollinator mutualism

    PubMed Central

    Zhang, Wenheng; Kramer, Elena M.; Davis, Charles C.

    2010-01-01

    The evolution of floral zygomorphy is an important innovation in flowering plants and is thought to arise principally from specialization on various insect pollinators. Floral morphology of neotropical Malpighiaceae is distinctive and highly conserved, especially with regard to symmetry, and is thought to be caused by selection by its oil-bee pollinators. We sought to characterize the genetic basis of floral zygomorphy in Malpighiaceae by investigating CYCLOIDEA2-like (CYC2-like) genes, which are required for establishing symmetry in diverse core eudicots. We identified two copies of CYC2-like genes in Malpighiaceae, which resulted from a gene duplication in the common ancestor of the family. A likely role for these loci in the development of floral zygomorphy in Malpighiaceae is demonstrated by the conserved pattern of dorsal gene expression in two distantly related neotropical species, Byrsonima crassifolia and Janusia guaranitica. Further evidence for this function is observed in a Malpighiaceae species that has moved to the paleotropics and experienced coincident shifts in pollinators, floral symmetry, and CYC2-like gene expression. The dorsal expression pat-tern observed in Malpighiaceae contrasts dramatically with their actinomorphic-flowered relatives, Centroplacaceae (Bhesa paniculata) and Elatinaceae (Bergia texana). In particular, B. texana exhibits a previously undescribed pattern of uniform CYC2 expression, suggesting that CYC2 expression among the actinomorphic ancestors of zygomorphic lineages may be much more complex than previously thought. We consider three evolutionary models that may have given rise to this patterning, including the hypothesis that floral zygomorphy in Malpighiaceae arose earlier than standard morphology-based character reconstructions suggest. PMID:20363959

  5. Radiation effects on organic materials in nuclear plants. Final report

    SciTech Connect

    Bruce, M B; Davis, M V

    1981-11-01

    A literature search was conducted to identify information useful in determining the lowest level at which radiation causes damage to nuclear plant equipment. Information was sought concerning synergistic effects of radiation and other environmental stresses. Organic polymers are often identified as the weak elements in equipment. Data on radiation effects are summarized for 50 generic name plastics and 16 elastomers. Coatings, lubricants, and adhesives are treated as separate groups. Inorganics and metallics are considered briefly. With a few noted exceptions, these are more radiation resistant than organic materials. Some semiconductor devices and electronic assemblies are extremely sensitive to radiation. Any damage threshold including these would be too low to be of practical value. With that exception, equipment exposed to less than 10/sup 4/ rads should not be significantly affected. Equipment containing no Teflon should not be significantly affected by 10/sup 5/ rads. Data concerning synergistic effects and radiation sensitization are discussed. The authors suggest correlations between the two effects.

  6. Volatile organic compound emission profiles of four common arctic plants

    NASA Astrophysics Data System (ADS)

    Vedel-Petersen, Ida; Schollert, Michelle; Nymand, Josephine; Rinnan, Riikka

    2015-11-01

    The biogenic volatile organic compound (BVOC) emissions from plants impact atmosphere and climate. The species-specific emissions, and thereby the atmospheric impact, of many plant species are still unknown. Knowledge of BVOC emission from arctic plants is particularly limited. The vast area and relatively high leaf temperature give the Arctic potential for emissions that cannot be neglected. This field study aimed to elucidate the BVOC emission profiles for four common arctic plant species in their natural environment during the growing season. BVOCs were sampled from aboveground parts of Empetrum hermaphroditum, Salix glauca, Salix arctophila and Betula nana using the dynamic enclosure technique and collection of volatiles in adsorbent cartridges, analyzed by gas chromatography-mass spectrometry. Sampling occurred three times: in late June/early July, in mid-July and in early August. E. hermaphroditum emitted the least BVOCs, dominated by sesquiterpenes (SQTs) and non-isoprenoid BVOCs. The Salix spp. emitted the most, dominated by isoprene. The emissions of B. nana were composed of about two-thirds non-isoprenoid BVOCs, with moderate amounts of monoterpenes (MTs) and SQTs. The total B. nana emissions and the MT and SQT emissions standardized to 30 °C were highest in the first measurement in early July, while the other species had the highest emissions in the last measurement in early August. As climate change is expected to increase plant biomass and change vegetation composition in the Arctic, the BVOC emissions from arctic ecosystems will also change. Our results suggest that if the abundance of deciduous shrubs like Betula and Salix spp. increases at the expense of slower growing evergreens like E. hermaphroditum, there is the potential for increased emissions of isoprene, MTs and non-isoprenoid BVOCs in the Arctic.

  7. Acute effects and exposure to organic compounds in road maintenance workers exposed to asphalt

    SciTech Connect

    Norseth, T.; Waage, J.; Dale, I. )

    1991-01-01

    Subjective symptoms and exposure to organic compounds were recorded in road repair and construction workers. Abnormal fatigue, reduced appetite, laryngeal/pharyngeal irritation, and eye irritation were recorded more often in such workers handling asphalt than in a corresponding reference group without asphalt exposure. Mean daily exposure to volatile compounds was only occasionally above 1 ppm. Mean exposure to asphalt fume was 0.358 mg/m3. There was no correlation between symptoms and total amount of volatile compounds, but a significant positive correlation was demonstrated between symptoms and some substances. The highest correlation was found for 1, 2, 4 trimethyl benzene. Symptoms increased with increasing asphalt temperature and with increasing concentrations of asphalt fumes. Amine addition did not increase the sum of symptoms, but soft asphalt seems to result in fewer symptoms than the harder types. Symptoms were not related to external factors like weather, traffic density, or specific working operations. As preventive measures, asphalt temperature should be kept below 150 degrees C, fume concentrations below 0.40 mg/m3, and if possible, the use of harder asphalt types which also require high temperatures should be avoided.

  8. Organization and maintenance of Drosophila telomeres: the roles of terminin and non-terminin proteins.

    PubMed

    Raffa, G D; Cenci, G; Ciapponi, L; Gatti, M

    2013-01-01

    Drosophila telomeres are elongated by occasional transposition of specialized retroelements rather than telomerase activity, and are assembled independently of the sequence of the DNA termini. Drosophila telomeres are capped by terminin, a complex formed by the HOAP, Moi, Ver and HipHop proteins that localize exclusively at telomeres and protect them from fusion events. Other proteins required to prevent end-to-end fusion include HP 1 Eff/UbcD 1, ATM, the components of the Mrel 1-Rad50-Nbs (MRN) complex, and the Woc transcription factor. The terminin proteins are encoded by fast-evolving genes and are not evolutionarily conserved outside the Drosophila species. In contrast, the non-terminin telomere capping proteins are not fast-evolving, do not localize only at telomeres and are conserved from yeasts to mammals. We propose that following telomerase loss, Drosophila rapidly evolved terminin to bind chromosome ends in a sequence-independent manner, and that non-terminin proteins did not evolve as rapidly as terminin because of the functional constraints imposed by their involvement in diverse cellular processes. This hypothesis suggests that the Drosophila non-terminin proteins might correspond to ancestral telomere-associated proteins with homologues in other organisms including humans. PMID:23795467

  9. Hydroperiod regime controls the organization of plant species in wetlands.

    PubMed

    Foti, Romano; del Jesus, Manuel; Rinaldo, Andrea; Rodriguez-Iturbe, Ignacio

    2012-11-27

    With urban, agricultural, and industrial needs growing throughout the past decades, wetland ecosystems have experienced profound changes. Most critically, the biodiversity of wetlands is intimately linked to its hydrologic dynamics, which in turn are being drastically altered by ongoing climate changes. Hydroperiod regimes, e.g., percentage of time a site is inundated, exert critical control in the creation of niches for different plant species in wetlands. However, the spatial signatures of the organization of plant species in wetlands and how the different drivers interact to yield such signatures are unknown. Focusing on Everglades National Park (ENP) in Florida, we show here that cluster sizes of each species follow a power law probability distribution and that such clusters have well-defined fractal characteristics. Moreover, we individuate and model those signatures via the interplay between global forcings arising from the hydroperiod regime and local controls exerted by neighboring vegetation. With power law clustering often associated with systems near critical transitions, our findings are highly relevant for the management of wetland ecosystems. In addition, our results show that changes in climate and land management have a quantifiable predictable impact on the type of vegetation and its spatial organization in wetlands. PMID:23150589

  10. Hydroperiod regime controls the organization of plant species in wetlands

    PubMed Central

    Foti, Romano; del Jesus, Manuel; Rinaldo, Andrea; Rodriguez-Iturbe, Ignacio

    2012-01-01

    With urban, agricultural, and industrial needs growing throughout the past decades, wetland ecosystems have experienced profound changes. Most critically, the biodiversity of wetlands is intimately linked to its hydrologic dynamics, which in turn are being drastically altered by ongoing climate changes. Hydroperiod regimes, e.g., percentage of time a site is inundated, exert critical control in the creation of niches for different plant species in wetlands. However, the spatial signatures of the organization of plant species in wetlands and how the different drivers interact to yield such signatures are unknown. Focusing on Everglades National Park (ENP) in Florida, we show here that cluster sizes of each species follow a power law probability distribution and that such clusters have well-defined fractal characteristics. Moreover, we individuate and model those signatures via the interplay between global forcings arising from the hydroperiod regime and local controls exerted by neighboring vegetation. With power law clustering often associated with systems near critical transitions, our findings are highly relevant for the management of wetland ecosystems. In addition, our results show that changes in climate and land management have a quantifiable predictable impact on the type of vegetation and its spatial organization in wetlands. PMID:23150589

  11. Conceptual hierarchical modeling to describe wetland plant community organization

    USGS Publications Warehouse

    Little, A.M.; Guntenspergen, G.R.; Allen, T.F.H.

    2010-01-01

    Using multivariate analysis, we created a hierarchical modeling process that describes how differently-scaled environmental factors interact to affect wetland-scale plant community organization in a system of small, isolated wetlands on Mount Desert Island, Maine. We followed the procedure: 1) delineate wetland groups using cluster analysis, 2) identify differently scaled environmental gradients using non-metric multidimensional scaling, 3) order gradient hierarchical levels according to spatiotem-poral scale of fluctuation, and 4) assemble hierarchical model using group relationships with ordination axes and post-hoc tests of environmental differences. Using this process, we determined 1) large wetland size and poor surface water chemistry led to the development of shrub fen wetland vegetation, 2) Sphagnum and water chemistry differences affected fen vs. marsh / sedge meadows status within small wetlands, and 3) small-scale hydrologic differences explained transitions between forested vs. non-forested and marsh vs. sedge meadow vegetation. This hierarchical modeling process can help explain how upper level contextual processes constrain biotic community response to lower-level environmental changes. It creates models with more nuanced spatiotemporal complexity than classification and regression tree procedures. Using this process, wetland scientists will be able to generate more generalizable theories of plant community organization, and useful management models. ?? Society of Wetland Scientists 2009.

  12. Maintenance strategies for greater availability

    SciTech Connect

    Pradhan, S. )

    1994-01-01

    Benchmark studies have confirmed there is a very wide gap in perceived world-class versus actual maintenance performance. To bridge this gap, companies will have to quickly adopt appropriate preventive and predictive maintenance practices and implement total productive maintenance (TPM) and reliability centered maintenance (RCM) practices. In process plants the whole approach to maintenance is slipshod, with a jumble of acronyms like PM/RM/CPM/flexing/multi-skilling, etc., giving a false sense of progress. North American maintenance benchmarks and British maintenance best practice give a very clear picture of current maintenance practices. Both of these studies indicate that breakdown maintenance is the dominant mode of maintenance in the progress industries. There are several key steps to be followed in establishing a strategy for maintenance improvements: (1) Recognize maintenance as an executive function; (2) Establish a solid maintenance performance database; (3) Review the existing plant maintenance practices; (4) Review and understand world-class maintenance practices; and (5) Design a master plan for a world-class system: Define the plant and maintenance resources; Define multi-skilling strategy; Define training and education levels for each job grouping; and Apply, and don't just talk about TPM and RCM.

  13. Enhanced human performance of utility maintenance programs

    SciTech Connect

    Fresco, A.; Haber, S.; O`Brien, J.

    1993-08-01

    Assuring the safe operation of a nuclear power plant depends, to a large extent, on how effectively one understands and manages the aging-related degradation that occurs in structures, systems, and components (SSCs). Aging-related degradation is typically managed through a nuclear plant`s maintenance program. A review of 44 Maintenance Team Inspection (MTI) Reports indicated that while some plant organizations appeared to assume a proactive mode in preventing aging-related failures of their SSCs important to safety, others seemed to be taking a passive or reactive mode. Across all plants, what is clearly needed, is a strong recognition of the importance of aging-related degradation and the use of existing organizational assets to effectively detect and mitigate those effects. Many of those assets can be enhanced by the consideration of organizational and management factors necessary for the implementation of an effective aging management program. This report provides a discussion of this program.

  14. [Chromosomal organization of the genomes of small-chromosome plants].

    PubMed

    Muravenko, O V; Zelenin, A V

    2009-11-01

    An effective approach to study the chromosome organization in genomes of plants with small chromosomes and/or with low-informative C-banding patterns was developed in the course of investigation of the karyotypes of cotton plant, camomile, flax, and pea. To increase the resolving power of chromosome analysis, methods were worked out for revealing early replication patterns on chromosomes and for artificial impairment of mitotic chromosome condensation with the use of a DNA intercalator, 9-aminoacridine (9-AMA). To estimate polymorphism of the patterns of C-banding of small chromosomes on preparations obtained with the use of 9-AMA, it is necessary to choose a length interval that must not exceed three average sizes of metaphase chromosomes without the intercalator. The use of 9-AMA increases the resolution of differential C- and OR-banding and the precision of physical chromosome mapping by the FISH method. Of particular importance in studying small chromosomes is optimization of the computer-aided methods used to obtain and process chromosome images. The complex approach developed for analysis of the chromosome organization in plant genomes was used to study the karyotypes of 24 species of the genus Linum L. It permitted their chromosomes to be identified for the first time, and, in addition, B chromosomes were discovered and studied in the karyotypes of the species of the section Syllinum. By similarity of the karyotypes, the studied flax species were distributed in eight groups in agreement with the clusterization of these species according to the results of RAPD analysis performed in parallel. Systematic positions and phylogenetic relationships of the studied flax species were verified. Out results can serve as an important argument in favour of the proposal to develop a special program for sequencing the genome of cultivated flax (L. usitatissimum L.), which is a major representative of small-chromosome species. PMID:20058798

  15. Facilities maintenance handbook

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This handbook is a guide for facilities maintenance managers. Its objective is to set minimum facilities maintenance standards. It also provides recommendations on how to meet the standards to ensure that NASA maintains its facilities in a manner that protects and preserves its investment in the facilities in a cost-effective manner while safely and efficiently performing its mission. This handbook implements NMI 8831.1, which states NASA facilities maintenance policy and assigns organizational responsibilities for the management of facilities maintenance activities on all properties under NASA jurisdiction. It is a reference for facilities maintenance managers, not a step-by-step procedural manual. Because of the differences in NASA Field Installation organizations, this handbook does not assume or recommend a typical facilities maintenance organization. Instead, it uses a systems approach to describe the functions that should be included in any facilities maintenance management system, regardless of its organizational structure. For documents referenced in the handbook, the most recent version of the documents is applicable. This handbook is divided into three parts: Part 1 specifies common definitions and facilities maintenance requirements and amplifies the policy requirements contained in NMI 8831. 1; Part 2 provides guidance on how to meet the requirements of Part 1, containing recommendations only; Part 3 contains general facilities maintenance information. One objective of this handbook is to fix commonality of facilities maintenance definitions among the Centers. This will permit the application of uniform measures of facilities conditions, of the relationship between current replacement value and maintenance resources required, and of the backlog of deferred facilities maintenance. The utilization of facilities maintenance system functions will allow the Centers to quantitatively define maintenance objectives in common terms, prepare work plans, and

  16. The stay-green phenotype of TaNAM-RNAi wheat plants is associated with maintenance of chloroplast structure and high enzymatic antioxidant activity.

    PubMed

    Checovich, Mariana L; Galatro, Andrea; Moriconi, Jorge I; Simontacchi, Marcela; Dubcovsky, Jorge; Santa-María, Guillermo E

    2016-07-01

    TaNAM transcription factors play an important role in controlling senescence, which in turn, influences the delivery of nitrogen, iron and other elements to the grain of wheat (Triticum aestivum) plants, thus contributing to grain nutritional value. While lack or diminished expression of TaNAMs determines a stay-green phenotype, the precise effect of these factors on chloroplast structure has not been studied. In this work we focused on the events undergone by chloroplasts in two wheat lines having either control or diminished TaNAM expression due to RNA interference (RNAi). It was found that in RNAi plants maintenance of chlorophyll levels and maximal photochemical efficiency of photosystem II were associated with lack of chloroplast dismantling. Flow cytometer studies and electron microscope analysis showed that RNAi plants conserved organelle ultrastructure and complexity. It was also found that senescence in control plants was accompanied by a low leaf enzymatic antioxidant activity. Lack of chloroplast dismantling in RNAi plants was associated with maintenance of protein and iron concentration in the flag leaf, the opposite being observed in control plants. These data provide a structural basis for the observation that down regulation of TaNAMs confers a functional stay-green phenotype and indicate that the low export of iron and nitrogen from the flag leaf of these plants is concomitant, within the developmental window studied, with lack of chloroplast degradation and high enzymatic antioxidant activity. PMID:27061370

  17. Studies in Ambulatory Care Quality Assessment in the Indian Health Service. Volume III: Comparison of Rural Private Practice, Health Maintenance Organizations, and the Indian Health Service.

    ERIC Educational Resources Information Center

    Nutting, Paul A.; And Others

    Utilizing a quality assessment methodology for ambulatory patient care currently under development by the Indian Health Service's (IHS) Office of Research and Development, comparisons were made between results derived from a pilot test in IHS service units, 2 metropolitan Health Maintenance Organizations (HMO), and 3 rural private practices.…

  18. Genomic organization of plant terpene synthases and molecular evolutionary implications.

    PubMed Central

    Trapp, S C; Croteau, R B

    2001-01-01

    Terpenoids are the largest, most diverse class of plant natural products and they play numerous functional roles in primary metabolism and in ecological interactions. The first committed step in the formation of the various terpenoid classes is the transformation of the prenyl diphosphate precursors, geranyl diphosphate, farnesyl diphosphate, and geranylgeranyl diphosphate, to the parent structures of each type catalyzed by the respective monoterpene (C(10)), sesquiterpene (C(15)), and diterpene synthases (C(20)). Over 30 cDNAs encoding plant terpenoid synthases involved in primary and secondary metabolism have been cloned and characterized. Here we describe the isolation and analysis of six genomic clones encoding terpene synthases of conifers, [(-)-pinene (C(10)), (-)-limonene (C(10)), (E)-alpha-bisabolene (C(15)), delta-selinene (C(15)), and abietadiene synthase (C(20)) from Abies grandis and taxadiene synthase (C(20)) from Taxus brevifolia], all of which are involved in natural products biosynthesis. Genome organization (intron number, size, placement and phase, and exon size) of these gymnosperm terpene synthases was compared to eight previously characterized angiosperm terpene synthase genes and to six putative terpene synthase genomic sequences from Arabidopsis thaliana. Three distinct classes of terpene synthase genes were discerned, from which assumed patterns of sequential intron loss and the loss of an unusual internal sequence element suggest that the ancestral terpenoid synthase gene resembled a contemporary conifer diterpene synthase gene in containing at least 12 introns and 13 exons of conserved size. A model presented for the evolutionary history of plant terpene synthases suggests that this superfamily of genes responsible for natural products biosynthesis derived from terpene synthase genes involved in primary metabolism by duplication and divergence in structural and functional specialization. This novel molecular evolutionary approach focused

  19. Organic pollution removal from coke plant wastewater using coking coal.

    PubMed

    Gao, Lihui; Li, Shulei; Wang, Yongtian; Sun, Hao

    2015-01-01

    Coke plant wastewater (CPW) is an intractable chemical wastewater, and it contains many toxic pollutants. This article presents the results of research on a semi-industrial adsorption method of coking wastewater treatment. As a sorbent, the coking coal (CC) was a dozen times less expensive than active carbon. The treatment was conducted within two scenarios, as follows: (1) adsorption after biological treatment of CPW with CC at 40 g L(-1); the chemical oxygen demand (COD) removal was 75.66%, and the concentration was reduced from 178.99 to 43.56 mg L(-1); (2) given an adsorption by CC of 250 g L(-1) prior to the biological treatment of CPW, the eliminations of COD and phenol were 58.08% and 67.12%, respectively. The CC that adsorbed organic pollution and was returned to the coking system might have no effect on both coke oven gas and coke. PMID:26114284

  20. A remote telepresence robotic system for inspection and maintenance of a nuclear power plant. Annual research status report

    SciTech Connect

    Crane, C.D. III; Tulenko, J.S.

    1993-02-01

    Progress in reported in the areas of environmental hardening; database/world modeling; man-machine interface; development of the Advanced Liquid Metal Reactor (ALMR) maintenance inspection robot design; and Articulated Transporter/Manipulator System (ATMS) development.

  1. Plants-rhizospheric organisms interaction in a manmade system with and without biogenous element limitation

    NASA Astrophysics Data System (ADS)

    Somova, L. A.; Pechurkin, N. S.; Polonsky, V. I.; Pisman, T. I.; Sarangova, A. B.; Andre, M.; Sadovskaya, G. M.

    1997-01-01

    The effect has been studied of inoculation of seeds of wheat with two species of rhizospheric microorganisms, - Pseudomonas fluorescens and Pseudomonas putida - on young plant growth with complete and with nitrogen deficit mineral nutrition. With complete mineral medium, plants grown from seeds inoculated with bacteria of Pseudomonas genus (experiment plants) have been found to have better growth over plants not inoculated with these bacteria (control plants). The experiment plants had increased transpiration and their biomass had higher organic nitrogen content. With nitrogen deficit medium, the plants inoculated with bacteria and those without them, have not revealed changes in growth. Neither case demonstrated competition of microorganisms with plants for nitrogen sources.

  2. Maintenance Trades Guidelines

    ERIC Educational Resources Information Center

    Weidner, Theodore J.

    2008-01-01

    In 2002, APPA published "Maintenance Staffing Guidelines for Educational Facilities," the first building maintenance trades staffing guideline designed to assist educational facilities professionals with their staffing needs. addresses how facilities professionals can determine the appropriate size and mix of their organization. Contents include…

  3. Soil organisms shape the competition between grassland plant species.

    PubMed

    Sabais, Alexander C W; Eisenhauer, Nico; König, Stephan; Renker, Carsten; Buscot, François; Scheu, Stefan

    2012-12-01

    Decomposers and arbuscular mycorrhizal fungi (AMF) both determine plant nutrition; however, little is known about their interactive effects on plant communities. We set up a greenhouse experiment to study effects of plant competition (one- and two-species treatments), Collembola (Heteromurus nitidus and Protaphorura armata), and AMF (Glomus intraradices) on the performance (above- and belowground productivity and nutrient uptake) of three grassland plant species (Lolium perenne, Trifolium pratense, and Plantago lanceolata) belonging to three dominant plant functional groups (grasses, legumes, and herbs). Generally, L. perenne benefited from being released from intraspecific competition in the presence of T. pratense and P. lanceolata. However, the presence of AMF increased the competitive strength of P. lanceolata and T. pratense against L. perenne and also modified the effects of Collembola on plant productivity. The colonization of roots by AMF was reduced in treatments with two plant species suggesting that plant infection by AMF was modified by interspecific plant interactions. Collembola did not affect total colonization of roots by AMF, but increased the number of mycorrhizal vesicles in P. lanceolata. AMF and Collembola both enhanced the amount of N and P in plant shoot tissue, but impacts of Collembola were less pronounced in the presence of AMF. Overall, the results suggest that, by differentially affecting the nutrient acquisition and performance of plant species, AMF and Collembola interactively modify plant competition and shape the composition of grassland plant communities. The results suggest that mechanisms shaping plant community composition can only be understood when complex belowground interactions are considered. PMID:22678109

  4. PREVENTIVE MAINTENANCE. HONEYWELL PLANNING GUIDE.

    ERIC Educational Resources Information Center

    Honeywell, Inc., Minneapolis, Minn.

    THIS HONEYWELL PAMPHLET DISCUSSES SOME ASPECTS OF PREVENTIVE MAINTENANCE OF AUTOMATIC CONTROLS, HEATING, VENTILATING, AND AIR CONDITIONING, AND COMPARES IN-PLANT WITH CONTRACT SERVICE, CONCLUDING THAT CONTRACT SERVICE IS PREFERABLE AND DESCRIBING A NUMBER OF MAINTENANCE PLANS WHICH THEY FURNISH. PREVENTIVE MAINTENANCE PROVIDES--(1) MORE EFFICIENT…

  5. Space shuttle maintenance program planning document

    NASA Technical Reports Server (NTRS)

    Brown, D. V.

    1972-01-01

    A means for developing a space shuttle maintenance program which will be acceptable to the development centers, the operators (KSC and AF), and the manufacturer is presented. The general organization and decision processes for determining the essential scheduled maintenance requirements for the space shuttle orbiter are outlined. The development of initial scheduled maintenance programs is discussed. The remaining maintenance, that is non-scheduled or non-routine maintenance, is directed by the findings of the scheduled maintenance program and the normal operation of the shuttle. The remaining maintenance consists of maintenance actions to correct discrepancies noted during scheduled maintenance tasks, nonscheduled maintenance, normal operation, or condition monitoring.

  6. Effects of lighting and air movement on temperatures in reproductive organs of plants in a closed plant growth facility

    NASA Astrophysics Data System (ADS)

    Kitaya, Y.; Hirai, H.

    Temperature increases in plant reproductive organs such as anthers and stigmas could cause fertility impediments and thus produce sterile seeds under artificial lighting conditions without adequately controlled environments in closed plant growth facilities. There is a possibility such a situation could occur in Bioregenerative Life Support Systems under microgravity conditions in space because there will be little natural convective or thermal mixing. This study was conducted to determine the temperature of the plant reproductive organs as affected by illumination and air movement under normal gravitational forces on the earth and to make an estimation of the temperature increase in reproductive organs in closed plant growth facilities under microgravity in space. Thermal images of reproductive organs of rice and strawberry were captured using infrared thermography at air temperatures of 10 11 °C. Compared to the air temperature, temperatures of petals, stigmas and anthers of strawberry increased by 24, 22 and 14 °C, respectively, after 5 min of lighting at an irradiance of 160 W m-2 from incandescent lamps. Temperatures of reproductive organs and leaves of strawberry were significantly higher than those of rice. The temperatures of petals, stigmas, anthers and leaves of strawberry decreased by 13, 12, 13 and 14 °C, respectively, when the air velocity was increased from 0.1 to 1.0 ms-1. These results show that air movement is necessary to reduce the temperatures of plant reproductive organs in plant growth facilities.

  7. Research collaborations can improve the use of organic amendments for plant-parasitic nematode management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The concept of utilizing organic amendments to manage plant-parasitic nematodes is not new, but the widespread implementation of this management practice has still not been realized. The use of organic amendments for plant-parasitic nematode management is a complex process requiring an understandin...

  8. Use of the virtual reality in maintenance operation at EDF

    SciTech Connect

    Nouailhas, B.; Tonnoir, S.; Laureillard, P.

    2006-07-01

    Today, a high level of availability for generating facilities is essential for electricity producers. In this context, optimizing the maintenance operation tasks is a necessity for EDF. To achieve this objective, EDF R and D has created the 3D Maintenance Project. The main goal of this project is to provide an organization and work methods linked with a 3D tool to support the maintenance staff in their tasks of coordination and moving packages during outages. In this paper present the moving packages tool and its experimentation in a nuclear power plant. (authors)

  9. International Atomic Energy Agency specialists meeting on experience in ageing, maintenance, and modernization of instrumentation and control systems for improving nuclear power plant availability

    SciTech Connect

    Not Available

    1993-10-01

    This report presents the proceedings of the Specialist`s Meeting on Experience in Aging, Maintenance and Modernization of Instrumentation and Control Systems for Improving Nuclear Power Plant Availability that was held at the Ramada Inn in Rockville, Maryland on May 5--7, 1993. The Meeting was presented in cooperation with the Electric Power Research Institute, Oak Ridge National Laboratory and the International Atomic Energy Agency. There were approximately 65 participants from 13 countries at the Meeting. Individual reports have been cataloged separately.

  10. Principles and limitations of stable isotopes in differentiating organic and conventional foodstuffs: 1. Plant products.

    PubMed

    Inácio, Caio Teves; Chalk, Phillip Michael; Magalhães, Alberto M T

    2015-01-01

    Among the lighter elements having two or more stable isotopes (H, C, N, O, S), δ(15)N appears to be the most promising isotopic marker to differentiate plant products from conventional and organic farms. Organic plant products vary within a range of δ(15)N values of +0.3 to +14.6%, while conventional plant products range from negative to positive values, i.e. -4.0 to +8.7%. The main factors affecting δ(15)N signatures of plants are N fertilizers, biological N2 fixation, plant organs and plant age. Correlations between mode of production and δ(13)C (except greenhouse tomatoes warmed with natural gas) or δ(34)S signatures have not been established, and δ(2)H and δ(18)O are unsuitable markers due to the overriding effect of climate on the isotopic composition of plant-available water. Because there is potential overlap between the δ(15)N signatures of organic and conventionally produced plant products, δ(15)N has seldom been used successfully as the sole criterion for differentiation, but when combined with complementary analytical techniques and appropriate statistical tools, the probability of a correct identification increases. The use of organic fertilizers by conventional farmers or the marketing of organic produce as conventional due to market pressures are additional factors confounding correct identification. The robustness of using δ(15)N to differentiate mode of production will depend on the establishment of databases that have been verified for individual plant products. PMID:24915332

  11. Characterization of culturable bacterial endophytes and their capacity to promote plant growth from plants grown using organic or conventional practices.

    PubMed

    Xia, Ye; DeBolt, Seth; Dreyer, Jamin; Scott, Delia; Williams, Mark A

    2015-01-01

    Plants have a diverse internal microbial biota that has been shown to have an important influence on a range of plant health attributes. Although these endophytes have been found to be widely occurring, few studies have correlated agricultural production practices with endophyte community structure and function. One agricultural system that focuses on preserving and enhancing soil microbial abundance and biodiversity is organic farming, and numerous studies have shown that organically managed system have increased microbial community characteristics. Herein, the diversity and specificity of culturable bacterial endophytes were evaluated in four vegetable crops: corn, tomato, melon, and pepper grown under organic or conventional practices. Endophytic bacteria were isolated from surface-sterilized shoot, root, and seed tissues and sequence identified. A total of 336 bacterial isolates were identified, and grouped into 32 species and five phyla. Among these, 239 isolates were from organically grown plants and 97 from those grown conventionally. Although a diverse range of bacteria were documented, 186 were from the Phylum Firmicutes, representing 55% of all isolates. Using the Shannon diversity index, we observed a gradation of diversity in tissues, with shoots and roots having a similar value, and seeds having the least diversity. Importantly, endophytic microbial species abundance and diversity was significantly higher in the organically grown plants compared to those grown using conventional practices, potentially indicating that organic management practices may increase endophyte presence and diversity. The impact that these endophytes could have on plant growth and yield was evaluated by reintroducing them into tomato plants in a greenhouse environment. Of the bacterial isolates tested, 61% were found to promote tomato plant growth and 50-64% were shown to enhance biomass accumulation, illustrating their potential agroecosystem application. PMID:26217348

  12. Characterization of culturable bacterial endophytes and their capacity to promote plant growth from plants grown using organic or conventional practices

    PubMed Central

    Xia, Ye; DeBolt, Seth; Dreyer, Jamin; Scott, Delia; Williams, Mark A.

    2015-01-01

    Plants have a diverse internal microbial biota that has been shown to have an important influence on a range of plant health attributes. Although these endophytes have been found to be widely occurring, few studies have correlated agricultural production practices with endophyte community structure and function. One agricultural system that focuses on preserving and enhancing soil microbial abundance and biodiversity is organic farming, and numerous studies have shown that organically managed system have increased microbial community characteristics. Herein, the diversity and specificity of culturable bacterial endophytes were evaluated in four vegetable crops: corn, tomato, melon, and pepper grown under organic or conventional practices. Endophytic bacteria were isolated from surface-sterilized shoot, root, and seed tissues and sequence identified. A total of 336 bacterial isolates were identified, and grouped into 32 species and five phyla. Among these, 239 isolates were from organically grown plants and 97 from those grown conventionally. Although a diverse range of bacteria were documented, 186 were from the Phylum Firmicutes, representing 55% of all isolates. Using the Shannon diversity index, we observed a gradation of diversity in tissues, with shoots and roots having a similar value, and seeds having the least diversity. Importantly, endophytic microbial species abundance and diversity was significantly higher in the organically grown plants compared to those grown using conventional practices, potentially indicating that organic management practices may increase endophyte presence and diversity. The impact that these endophytes could have on plant growth and yield was evaluated by reintroducing them into tomato plants in a greenhouse environment. Of the bacterial isolates tested, 61% were found to promote tomato plant growth and 50–64% were shown to enhance biomass accumulation, illustrating their potential agroecosystem application. PMID:26217348

  13. Comparison of endogenous loss and maintenance need for minerals in rainbow trout (Oncorhynchus mykiss) fed fishmeal or plant ingredient-based diets.

    PubMed

    Antony Jesu Prabhu, P; Kaushik, S J; Mariojouls, C; Surget, A; Fontagné-Dicharry, S; Schrama, J W; Geurden, I

    2015-02-01

    Mineral needs as affected by changes in dietary protein and oil sources were studied in rainbow trout. Duplicate groups (n = 30 fish per replicate) of rainbow trout (initial BW: 37 g) were fed either a fish meal/fish oil-based (M) or a complete plant ingredient (V)-based diet at four graded ration (R) levels [apparent satiation (AS), R75, R50 and R25 % of AS]; one treatment group was maintained under starvation. The feeding trial lasted 12 weeks at a water temperature of 17 °C. Dietary intake, apparent digestibility and initial and final whole-body composition data were used to calculate mineral gain which was regressed against digestible mineral intake (both expressed as mg or µg kg(-0.8) day(-1)). Starvation loss (SL), endogenous loss of fed fish (ELF, y-intercept at x = 0) and point of intake for zero balance (PZB, x-intercept at y = 0) were used as estimates of maintenance requirements. SL provided the lowest estimate, ELF provided the net requirement of a mineral for maintenance and PZB provided the digestible dietary intake required to meet maintenance (SL < ELF < PZB). Dietary ingredient composition did not significantly affect the digestible mineral supply required for maintenance (PZB) for any of the minerals (P, Mg, K, Cu and Zn) studied. However, ELF of micro-minerals such as Cu and Zn were significantly affected. The ELF of Cu was significantly lower and that of Zn was significantly higher in V group compared with M-fed fish. Further studies on the effects of such changes in dietary formulations on micro-mineral metabolism are warranted. PMID:25500770

  14. Organization of health care in small plants in the USA

    PubMed Central

    Miller, Seward E.

    1955-01-01

    In the USA, the concept of an occupational health programme has grown steadily, and now embraces the total health of the worker. Elements of basic in-plant health programmes have been identified and patterns developed for successful operation. Today, health services in small plants still fall far short of optimal requirements. No more than 5% of workers in small plants enjoy the benefit of occupational health services. The main reason for the arrested development of these programmes is the lack of organizational and administrative techniques for providing health services in small plants. Recently, however, several projects have demonstrated that these difficulties can be overcome, and the future development of such programmes in small plants thus looks hopeful. Other recent developments hold promise of strengthening the health services available to workers. Union health centres, now being established in increasing numbers, offer the workers varying services, ranging from diagnostic and preventive procedures to complete medical care. Further benefits to both the worker and his family are being provided under collective bargaining agreements by voluntary health-insurance schemes. In addition to making services available to large numbers of workers previously not covered, the development of both union health centres and the prepaid health-insurance schemes offer future possibilities for integration of these programmes into the preventive and diagnostic services offered in the plant. Finally, governmental occupational health agencies, in addition to their industrial hygiene activities, are taking an increasing interest in the establishment and development of in-plant health programmes. PMID:13276820

  15. The Application of Advanced Cultivation Techniques in the Long Term Maintenance of Space Flight Plant Biological Systems

    NASA Technical Reports Server (NTRS)

    Heyenga, A. G.

    2003-01-01

    The development of the International Space Station (ISS) presents extensive opportunities for the implementation of long duration space life sciences studies. Continued attention has been placed in the development of plant growth chamber facilities capable of supporting the cultivation of plants in space flight microgravity conditions. The success of these facilities is largely dependent on their capacity to support the various growth requirements of test plant species. The cultivation requirements for higher plant species are generally complex, requiring specific levels of illumination, temperature, humidity, water, nutrients, and gas composition in order to achieve normal physiological growth and development. The supply of water, nutrients, and oxygen to the plant root system is a factor, which has proven to be particularly challenging in a microgravity space flight environment. The resolution of this issue is particularly important for the more intensive crop cultivation of plants envisaged in Nasa's advanced life support initiative. BioServe Space Technologies is a NASA, Research Partnership Center (RPC) at the University of Colorado, Boulder. BioServe has designed and operated various space flight plant habitat systems, and placed specific emphasis on the development and enhanced performance of subsystem components such as water and nutrient delivery, illumination, gas exchange and atmosphere control, temperature and humidity control. The further development and application of these subsystems to next generation habitats is of significant benefit and contribution towards the development of both the Space Plant biology and the Advanced Life Support Programs. The cooperative agreement between NASA Ames Research center and BioServe was established to support the further implementation of advanced cultivation techniques and protocols to plant habitat systems being coordinated at NASA Ames Research Center. Emphasis was placed on the implementation of passive

  16. The organization of plant communities: negative plant-soil feedbacks and semiarid grasslands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Estimates of species losses and evidence of positive plant diversity-productivity relationships have spurred interest in understanding the mechanism(s) regulating species coexistence and relative abundance. Plant-soil biota feedbacks appear to affect plant diversity and community structure by eithe...

  17. Induction and maintenance of DNA methylation in plant promoter sequences by apple latent spherical virus-induced transcriptional gene silencing.

    PubMed

    Kon, Tatsuya; Yoshikawa, Nobuyuki

    2014-01-01

    Apple latent spherical virus (ALSV) is an efficient virus-induced gene silencing vector in functional genomics analyses of a broad range of plant species. Here, an Agrobacterium-mediated inoculation (agroinoculation) system was developed for the ALSV vector, and virus-induced transcriptional gene silencing (VITGS) is described in plants infected with the ALSV vector. The cDNAs of ALSV RNA1 and RNA2 were inserted between the cauliflower mosaic virus 35S promoter and the NOS-T sequences in a binary vector pCAMBIA1300 to produce pCALSR1 and pCALSR2-XSB or pCALSR2-XSB/MN. When these vector constructs were agroinoculated into Nicotiana benthamiana plants with a construct expressing a viral silencing suppressor, the infection efficiency of the vectors was 100%. A recombinant ALSV vector carrying part of the 35S promoter sequence induced transcriptional gene silencing of the green fluorescent protein gene in a line of N. benthamiana plants, resulting in the disappearance of green fluorescence of infected plants. Bisulfite sequencing showed that cytosine residues at CG and CHG sites of the 35S promoter sequence were highly methylated in the silenced generation zero plants infected with the ALSV carrying the promoter sequence as well as in progeny. The ALSV-mediated VITGS state was inherited by progeny for multiple generations. In addition, induction of VITGS of an endogenous gene (chalcone synthase-A) was demonstrated in petunia plants infected with an ALSV vector carrying the native promoter sequence. These results suggest that ALSV-based vectors can be applied to study DNA methylation in plant genomes, and provide a useful tool for plant breeding via epigenetic modification. PMID:25426109

  18. Predicting the accumulation of organic contaminants from soil by plants.

    PubMed

    Cropp, Roger A; Hawker, Darryl W; Boonsaner, Maliwan

    2010-11-01

    Analytic expressions for maximum chemical concentration attained in plants, and time this takes for uptake from surrounding soil were derived from a simple two-compartment soil/water-plant model. To illustrate, for the antibiotic norflxacin undergoing first order loss in the soil/water phase with a rate constant of 0.544 days⁻¹, maximum concentration in soybean P(MAX) is predicted to occur after 2.79 days exposure and be independent of initial soil/water concentration SW₀ of 52.5 mg kg⁻¹ dry weight. For soybean, the relationship between P(MAX) and SW₀ is P(MAX) = 0.047SW₀, resulting in predicted maximum levels of 2.20 mg kg⁻¹ dry weight. Modelled plant concentrations agreed well with experimental data (R² = 0.91). PMID:21069277

  19. Plant sphingolipids: Their importance in cellular organization and adaption.

    PubMed

    Michaelson, Louise V; Napier, Johnathan A; Molino, Diana; Faure, Jean-Denis

    2016-09-01

    Sphingolipids and their phosphorylated derivatives are ubiquitous bio-active components of cells. They are structural elements in the lipid bilayer and contribute to the dynamic nature of the membrane. They have been implicated in many cellular processes in yeast and animal cells, including aspects of signaling, apoptosis, and senescence. Although sphingolipids have a better defined role in animal systems, they have been shown to be central to many essential processes in plants including but not limited to, pollen development, signal transduction and in the response to biotic and abiotic stress. A fuller understanding of the roles of sphingolipids within plants has been facilitated by classical biochemical studies and the identification of mutants of model species. Recently the development of powerful mass spectrometry techniques hailed the advent of the emerging field of lipidomics enabling more accurate sphingolipid detection and quantitation. This review will consider plant sphingolipid biosynthesis and function in the context of these new developments. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner. PMID:27086144

  20. Hybridization and evolution of invasiveness in plants and other organisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Less than a decade ago, we proposed that hybridization could serve as a stimulus for the evolution of invasiveness in plants (Ellstrand and Schierenbeck Proc Nat Acad Sci USA 97:7043–7050, 2000). A substantial amount of research has taken place on that topic since the publication of that paper, stim...

  1. ORGANIC PESTICIDE MODIFICATION OF SPECIES INTERACTIONS USING ANNUAL PLANT COMMUNITIES

    EPA Science Inventory

    A method is proposed and tested for assessing multispecies responses to three pesticides (atrazine, 2,4,D and malathion). Pesticides were applied at two concentrations, mon model plant communities grown in raised beds using soil containing a natural weed bank. over by species was...

  2. Maintenance Budgeting.

    ERIC Educational Resources Information Center

    Smith, J. McCree

    Three methods for the preparation of maintenance budgets are discussed--(1) a traditional method, inconclusive and obsolete, based on gross square footage, (2) the formula approach method based on building classification (wood-frame, masonry-wood, masonry-concrete) with maintenance cost factors for each type plus custodial service rates by type of…

  3. Preventative Maintenance.

    ERIC Educational Resources Information Center

    Migliorino, James

    Boards of education must be convinced that spending money up front for preventive maintenance will, in the long run, save districts' tax dollars. A good program of preventive maintenance can minimize disruption of service; reduce repair costs, energy consumption, and overtime; improve labor productivity and system equipment reliability; handle…

  4. Software Maintenance.

    ERIC Educational Resources Information Center

    Cannon, Glenn; Jobe, Holly

    Proper cleaning and storage of audiovisual aids is outlined in this brief guide. Materials and equipment needed for first line maintenance are listed, as well as maintenance procedures for records, audio and video tape, film, filmstrips, slides, realia, models, prints, graphics, maps, and overhead transparencies. A 15-item quiz on software…

  5. Maintenance Downtime

    Atmospheric Science Data Center

    2013-07-10

    ... will be unavailable March 5, 2013 8:00 am to 5:00 pm due to database maintenance. Date(s):  Tuesday, March 5, 2013 ... will be unavailable March 5, 2013 8:00 am to 5:00 pm due to database maintenance. ...

  6. The impact of plant-based antimicrobials on sensory properties of organic leafy greens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant extracts and essential oils are well known for their antibacterial activity. However, studies concerning their effect on the organoleptic properties of treated foods are limited. The objective was to study the sensory attributes of organic leafy greens treated with plant antimicrobials and ide...

  7. EMISSION OF VOLATILE ORGANIC COMPOUNDS FROM DRUM-MIX ASPHALT PLANTS

    EPA Science Inventory

    This research program was undertaken in order to develop a quantitative estimate of the emission of volatile organic compounds (VOCs) from drum-mix asphalt plants. The study was carried out by field sampling of five drum-mix plants under a variety of operating conditions. Include...

  8. Co-adaptationary aspects of the underground communication between plants and other organisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil microbial communities are comprised of a vast array of bacteria, fungi, nematodes and other organisms. It is becoming increasingly clear that these communities are not passively determined but actively regulated by plants. This chapter discusses the role plant root exudates play in the active r...

  9. Volatile organic compounds as non-invasive markers for plant phenotyping.

    PubMed

    Niederbacher, B; Winkler, J B; Schnitzler, J P

    2015-09-01

    Plants emit a great variety of volatile organic compounds (VOCs) that can actively participate in plant growth and protection against biotic and abiotic stresses. VOC emissions are strongly dependent on environmental conditions; the greatest ambiguity is whether or not the predicted change in climate will influence and modify plant-pest interactions that are mediated by VOCs. The constitutive and induced emission patterns between plant genotypes, species, and taxa are highly variable and can be used as pheno(chemo)typic markers to distinguish between different origins and provenances. In recent years significant progress has been made in molecular and genetic plant breeding. However, there is actually a lack of knowledge in functionally linking genotypes and phenotypes, particularly in analyses of plant-environment interactions. Plant phenotyping, the assessment of complex plant traits such as growth, development, tolerance, resistance, etc., has become a major bottleneck, and quantitative information on genotype-environment relationships is the key to addressing major future challenges. With increasing demand to support and accelerate progress in breeding for novel traits, the plant research community faces the need to measure accurately increasingly large numbers of plants and plant traits. In this review article, we focus on the promising outlook of VOC phenotyping as a fast and non-invasive measure of phenotypic dynamics. The basic principle is to define plant phenotypes according to their disease resistance and stress tolerance, which in turn will help in improving the performance and yield of economically relevant plants. PMID:25969554

  10. A partition-limited model for the plant uptake of organic contaminants from soil and water

    USGS Publications Warehouse

    Chiou, C.T.; Sheng, G.; Manes, M.

    2001-01-01

    In dealing with the passive transport of organic contaminants from soils to plants (including crops), a partition-limited model is proposed in which (i) the maximum (equilibrium) concentration of a contaminant in any location in the plant is determined by partition equilibrium with its concentration in the soil interstitial water, which in turn is determined essentially by the concentration in the soil organic matter (SOM) and (ii) the extent of approach to partition equilibrium, as measured by the ratio of the contaminant concentrations in plant water and soil interstitial water, ??pt (??? 1), depends on the transport rate of the contaminant in soil water into the plant and the volume of soil water solution that is required for the plant contaminant level to reach equilibrium with the external soil-water phase. Through reasonable estimates of plant organic-water compositions and of contaminant partition coefficients with various plant components, the model accounts for calculated values of ??pt in several published crop-contamination studies, including near-equilibrium values (i.e., ??pt ??? 1) for relatively water-soluble contaminants and lower values for much less soluble contaminants; the differences are attributed to the much higher partition coefficients of the less soluble compounds between plant lipids and plant water, which necessitates much larger volumes of the plant water transport for achieving the equilibrium capacities. The model analysis indicates that for plants with high water contents the plant-water phase acts as the major reservoir for highly water-soluble contaminants. By contrast, the lipid in a plant, even at small amounts, is usually the major reservoir for highly water-insoluble contaminants.

  11. Guidelines for the content of records to support nuclear power plant operation, maintenance, and modification (NCIG-08): Volume 2, Appendixes A, B, and C: Final report

    SciTech Connect

    Reedy, R.F.; Hegglin, D.P.

    1988-11-01

    The record systems at many nuclear power plant sites are becoming overloaded with unnecessary and superfluous records. The reason for this overload is that although the Codes and Standards list the record types to be retained, there is no definition for the contents of the records. This encourages varied interpretations which often lead to the approach of ''save everything''. This document provides guidelines for the content of records to support nuclear power plant operation, maintenance and modification. These Guidelines are based on an engineering approach to identify which data in the records are of ''significant value'' in (1) demonstrating capability for safe operation; (2) maintaining, reworking, repairing, replacing, or modifying an item; (3) determining the cause of an accident or malfunction of an item; and (4) providing required baseline for in-service inspection. Particular topical issues affecting record retention needs, such as plant life extension activities, may require additional evaluation of data or records. By identifying the data to be retained in the records, it is possible to modify the record management system to substantially reduce the amount of unnecessary information being retained in the records. These Guidelines will provide for more uniform interpretation of requirements. This document, Volume 2, contains Appendices A, B and C.

  12. Guidelines for the content of records to support nuclear power plant operation, maintenance, and modification (NCIG-08): Volume 1, Guidelines: Final report

    SciTech Connect

    Reedy, R.F.; Hegglin, D.P.

    1988-11-01

    The record systems at many nuclear power plant sites are becoming overloaded with unnecessary and superfluous records. The reason for this overload is that although the Codes and Standards list the record types to be retained, there is no definition for the contents of the records. This encourages varied interpretations which often lead to the approach of ''save everything''. This document provides guidelines for the content of records to support nuclear power plant operation, maintenance and modification. These Guidelines are based on an engineering approach to identify which data in the records are of ''significant value'' in (1) demonstrating capability for safe operation; (2) maintaining, reworking, repairing, replacing, or modifying an item; (3) determining the cause of an accident or malfunction of an item; and (4) providing required baseline data for in-service inspection. Particular topical issues affecting record retention needs, such as plant life extension activities, may require additional evaluation of data or records. By identifying the data to be retained in the records, it is possible to modify the record management system to substantially reduce the amount of unnecessary information being retained in the records. These Guidelines will provide for more uniform interpretation of requirements. The Guidelines are meant as an interpretation of current Codes, Standards and Regulatory Guides, and not as new requirements. Should any conflict exist between these Guidelines and the specified requirements of the NRC Regulations, the regulations govern. 4 tabs.

  13. Surveillance and maintenance report on decontamination and decommissioning and remedial action activities at the Oak Ridge Y-12 plant, Oak Ridge, Tennessee. Fiscal year 1996

    SciTech Connect

    King, H.L.; Sollenberger, M.L.; Sparkman, D.E.; Reynolds, R.M.; Wayland, G.S.

    1996-12-01

    The Oak Ridge Y-12 Plant Decontamination and Decommissioning (D&D) and Remedial Action (RA) programs are part of the Environmental Restoration (ER) Division and are funded by the Office of Environmental Management (EM-40). Building 9201-4 (known as Alpha-4), three sites located within Building 9201-3 (the Oil Storage Tank, the Molten Salt Reactor Experiment Fuel Handling Facility, and the Coolant Salt Technology Facility), and Building 9419-1 (the Decontamination Facility) are currently the facilities at the Y-12 Plant included in the D&D program. The RA program provides surveillance and maintenance (S&M) and program management of ER sites at the Y-12 Plant, including selected sites listed in Appendix C of the Federal Facilities Agreement (FFA), sites listed in the Hazardous and Solid Waste Amendment (HSWA) permit Solid Waste Management Unit (SWM-U) list, and sites currently closed or undergoing post-closure activities under the Resource Conservation and Recovery Act of 1976 (RCRA) or the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). This report communicates the status of the program plans and specific S&M activities for the D&D and RA programs.

  14. A bioassay experience and lessons learned on the internal contamination of (131)I during a maintenance period in a Korean nuclear power plant.

    PubMed

    Kim, Hee Geun; Kong, Tae Young

    2012-08-01

    During a maintenance period at a Korean nuclear power plant, internal exposure of radiation workers occurred by the inhalation of (131)I that was released into the reactor building from a primary system opening due to defective fuels. The internal activity in radiation workers contaminated by (131)I was immediately measured using a whole body counter (WBC). A whole body counting was performed again a few days later, considering the factors of equilibrium in the body. The intake and the committed effective dose were estimated based on the WBC results. The intake was also calculated by hand, based on both the entrance records to the reactor building, and the counted results of the air concentration for (131)I were compared with the whole body counting results. PMID:22323659

  15. Plant volatile organic compounds (VOCs) in ozone (O3) polluted atmospheres: the ecological effects.

    PubMed

    Pinto, Delia M; Blande, James D; Souza, Silvia R; Nerg, Anne-Marja; Holopainen, Jarmo K

    2010-01-01

    Tropospheric ozone (O3) is an important secondary air pollutant formed as a result of photochemical reactions between primary pollutants, such as nitrogen oxides (NOx), and volatile organic compounds (VOCs). O3 concentrations in the lower atmosphere (troposphere) are predicted to continue increasing as a result of anthropogenic activity, which will impact strongly on wild and cultivated plants. O3 affects photosynthesis and induces the development of visible foliar injuries, which are the result of genetically controlled programmed cell death. It also activates many plant defense responses, including the emission of phytogenic VOCs. Plant emitted VOCs play a role in many eco-physiological functions. Besides protecting the plant from abiotic stresses (high temperatures and oxidative stress) and biotic stressors (competing plants, micro- and macroorganisms), they drive multitrophic interactions between plants, herbivores and their natural enemies e.g., predators and parasitoids as well as interactions between plants (plant-to-plant communication). In addition, VOCs have an important role in atmospheric chemistry. They are O3 precursors, but at the same time are readily oxidized by O3, thus resulting in a series of new compounds that include secondary organic aerosols (SOAs). Here, we review the effects of O3 on plants and their VOC emissions. We also review the state of current knowledge on the effects of ozone on ecological interactions based on VOC signaling, and propose further research directions. PMID:20084432

  16. Effect of mechanical damage on emission of volatile organic compounds from plant leaves and implications for evaluation of host plant specificity of prospective biological control agents of weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Assessment of host plant specificity is a critical step in the evaluation of classical biological control agents of weeds, which is necessary for avoiding possible damage to nontarget plants. Volatile organic compounds (VOC) emitted by plants likely play an important role in determining which plant...

  17. BIOAVAILABILITY TO PLANTS OF SLUDGE-BORNE TOXIC ORGANICS

    EPA Science Inventory

    Large numbers of man-made organic chemicals occur in sewage sludge and many are thought to represent an environmental hazard. his is particularly true of the compounds classified as priority pollutants (TOs) which typically occur in sludges in the mg/kg concentration range. oncer...

  18. Organic Chemistry and the Native Plants of the Sonoran Desert: Conversion of Jojoba Oil to Biodiesel

    ERIC Educational Resources Information Center

    Daconta, Lisa V.; Minger, Timothy; Nedelkova, Valentina; Zikopoulos, John N.

    2015-01-01

    A new, general approach to the organic chemistry laboratory is introduced that is based on learning about organic chemistry techniques and research methods by exploring the natural products found in local native plants. As an example of this approach for the Sonoran desert region, the extraction of jojoba oil and its transesterification to…

  19. Contribution of plant lignin to the soil organic matter formation and stabilization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lignin is the third most abundant plant constituent after cellulose and hemicellulose and thought to be one of the building blocks for soil organic matter formation. Lignin can be used as a predictor for long-term soil organic matter stabilization and C sequestration. Soils and humic acids from fo...

  20. Yeast Biocontrol of a Fungal Plant Disease: A Model for Studying Organism Interrelationships

    ERIC Educational Resources Information Center

    Chanchaichaovivat, Arun; Panijpan, Bhinyo; Ruenwongsa, Pintip

    2008-01-01

    An experiment on the action of the yeast, "Saccharomyces cerevisiae", against a fungal plant disease is proposed for secondary students (Grade 11) to support their study of organism interrelationship. This biocontrol experiment serves as the basis for discussing relationships among three organisms (red chilli fruit, "Saccharomyces cerevisiae," and…

  1. EPRI research publications, products, and expertise in maintenance

    SciTech Connect

    Not Available

    1991-05-01

    The intent of this revision to the original NP-7014D cross-referencing index is to identify EPRI expertise and the associated EPRI products with respect to the Maintenance Issues. Whether prepared by the Nuclear Maintenance Applications Center (NMAC), or other organizations within EPRI, they are being included for information. This document was compiled from the EPRI resource catalogs database. The EPRI/NMAC Project Manager Expertise List provides contact phone numbers for selected maintenance subjects. The EPRI Research, Technical Reports, and Products information provides a listing and brief description of EPRI projects and products by selected maintenance subjects. Additionally, listings of EPRI maintenance-related documents are sorted by document number and title. Certain research reports which contain software have been intentionally omitted due to the lack of (at most utility maintenance departments) computer hardware. The Nuclear Maintenance Applications Center (NMAC) has not reviewed or endorsed the EPRI products listed in this document, except for those produced by NMAC. The planned updating of this cross-reference index is semiannually. Should any further assistance be required for plant-related maintenance problems, contact NMAC at (800) 356-7448.

  2. Sorption of trace organics and engineered nanomaterials onto wetland plant material.

    PubMed

    Sharif, Fariya; Westerhoff, Paul; Herckes, Pierre

    2013-01-01

    Wastewater treatment plant (WWTP) effluents are sources for emerging pollutants, including organic compounds and engineered nanomaterials (ENMs), which then flow into aquatic systems. In this article, natural attenuation of pollutants by constructed wetland plants was investigated using lab-scale microcosm and batch sorption studies. The microcosms were operated at varying hydraulic residence times (HRTs) and contained decaying plant materials. Representative organic compounds and ENMs were simultaneously spiked into the microcosm influent, along with a conservative tracer (bromide), and then monitored in the effluent over time. It was observed that a more hydrophobic compound-natural estrogen achieved better removal than a polar organic compound – para-chlorobenzoic acid (pCBA), which mimics the behaviour of the tracer. Batch sorption experiments showed that estrogen has higher sorption affinity than pCBA, highlighting the importance of sorption to the plant materials as a removal process for the organic contaminants in the microcosms. Wetland plants were also found a potential sorbent for ENMs. Two different ENMs (nano-silver and aqueous fullerenes) were included in this study, both of which experienced comparable removal in the microcosms. Relative to the tracer, the highest removal of ENMs and trace organics was 60% and 70%, respectively. A more than two-fold increase in HRT increased the removal efficiency of the contaminants in the range of 20–60%. The outcome of this study supports that plant materials of wetlands can play an important role in removing emerging pollutants from WWTP effluent. PMID:24592444

  3. A Late Devonian fertile organ with seed plant affinities from China.

    PubMed

    Wang, Deming; Liu, Le; Guo, Yun; Xue, Jinzhuang; Meng, Meicen

    2015-01-01

    Seed plants underwent first major evolutionary radiation in the Late Devonian (Famennian), as evidenced by the numerous ovules described to date. However, the early pollen organs are underrepresented, so that their structure and evolution remain poorly known. Here we report a new taxon of pollen organ Placotheca minuta from the Late Devonian. The synangium consists of many basally and more or less laterally fused microsporangia borne on the margin of a pad. The prepollen is spherical and trilete. The appearance of Famennian synangia especially in Placotheca does not support the current understanding that the earliest pollen organs closely resembled the fructifications of the ancestral progymnosperms. Placotheca indicates earlier diversification of pollen organs than previously expected and is highly derived among the early pollen organs with trilete prepollen. It is suggested that, immediately after the origination of seed plants, pollen organs had evolved at a rapid rate, whereas their prepollen remained primitively spore-like. PMID:26022973

  4. A Late Devonian Fertile Organ with Seed Plant Affinities from China

    PubMed Central

    Wang, Deming; Liu, Le; Guo, Yun; Xue, Jinzhuang; Meng, Meicen

    2015-01-01

    Seed plants underwent first major evolutionary radiation in the Late Devonian (Famennian), as evidenced by the numerous ovules described to date. However, the early pollen organs are underrepresented, so that their structure and evolution remain poorly known. Here we report a new taxon of pollen organ Placotheca minuta from the Late Devonian. The synangium consists of many basally and more or less laterally fused microsporangia borne on the margin of a pad. The prepollen is spherical and trilete. The appearance of Famennian synangia especially in Placotheca does not support the current understanding that the earliest pollen organs closely resembled the fructifications of the ancestral progymnosperms. Placotheca indicates earlier diversification of pollen organs than previously expected and is highly derived among the early pollen organs with trilete prepollen. It is suggested that, immediately after the origination of seed plants, pollen organs had evolved at a rapid rate, whereas their prepollen remained primitively spore-like. PMID:26022973

  5. Organically managed soils reduce internal colonization of tomato plants by Salmonella enterica serovar Typhimurium.

    PubMed

    Gu, Ganyu; Cevallos-Cevallos, Juan M; Vallad, Gary E; van Bruggen, Ariena H C

    2013-04-01

    A two-phase experiment was conducted twice to investigate the effects of soil management on movement of Salmonella enterica Typhimurium in tomato plants. In the first phase, individual leaflets of 84 tomato plants grown in conventional or organic soils were dip inoculated two to four times before fruiting with either of two Salmonella Typhimurium strains (10(9) CFU/ml; 0.025% [vol/vol] Silwet L-77). Inoculated and adjacent leaflets were tested for Salmonella spp. densities for 30 days after each inoculation. Endophytic bacterial communities were characterized by polymerase chain reaction denaturing gradient gel electrophoresis before and after inoculation. Fruit and seed were examined for Salmonella spp. incidence. In phase 2, extracted seed were planted in conventional soil, and contamination of leaves and fruit of the second generation was checked. More Salmonella spp. survived in inoculated leaves on plants grown in conventional than in organic soil. The soil management effect on Salmonella spp. survival was confirmed for tomato plants grown in two additional pairs of soils. Endophytic bacterial diversities of tomato plants grown in conventional soils were significantly lower than those in organic soils. All contaminated fruit (1%) were from tomato plants grown in conventional soil. Approximately 5% of the seed from infested fruit were internally contaminated. No Salmonella sp. was detected in plants grown from contaminated seed. PMID:23506364

  6. Psychrotolerant actinomycetes of plants and organic horizons in tundra and taiga soils

    NASA Astrophysics Data System (ADS)

    Dubrova, M. S.; Zenova, G. M.; Yakushev, A. V.; Manucharova, N. A.; Makarova, E. P.; Zvyagintsev, D. G.; Chernov, I. Yu.

    2013-08-01

    It has been revealed that in organic horizons and plants of the tundra and taiga ecosystems under low temperatures, actinomycetal complexes form. The population density of psychrotolerant actinomycetes in organic horizons and plants reaches tens and hundreds of thousands CFU/g of substrate or soil, and decreases in the sequence litters > plants > soils > undecomposed plant remains > moss growths. The mycelium length of psychrotolerant actinomycetes reaches 220 m/g of substrate. Application of the FISH method has demonstrated that metabolically active psychrotolerant bacteria of the phylum Actinobacteria constitute 30% of all metabolically active psychrotolerant representatives of the Bacterià domain of the prokaryotic microbial community of soils and plants. Psychrotolerant actinomycetes in tundra and taiga ecosystems possess antimicrobial properties.

  7. Hydrogen generation in CSP plants and maintenance of DPO/BP heat transfer fluids - A simulation approach

    NASA Astrophysics Data System (ADS)

    Kuckelkorn, Thomas; Jung, Christian; Gnädig, Tim; Lang, Christoph; Schall, Christina

    2016-05-01

    The ageing of diphenyl oxide/ biphenyl (DPO/BP) Heat Transfer Fluids (HTFs) implies challenging tasks for operators of parabolic trough power plants in order to find the economic optimum between plant performance and O&M costs. Focusing on the generation of hydrogen, which is effecting from the HTF ageing process, the balance of hydrogen pressure in the HTF is simulated for different operation scenarios. Accelerated build-up of hydrogen pressure in the HTF is causing increased permeation into the annular vacuum space of the installed receivers and must be avoided in order to maintain the performance of these components. Therefore, the effective hydrogen partial pressure in the HTF has to be controlled and limited according to the specified values so that the vacuum lifetime of the receivers and the overall plant performance can be ensured. In order to simulate and visualize the hydrogen balance of a typical parabolic trough plant, initially a simple model is used to calculate the balance of hydrogen in the system and this is described. As input data for the simulation, extrapolated hydrogen generation rates have been used, which were calculated from results of lab tests performed by DLR in Cologne, Germany. Hourly weather data, surface temperatures of the tubing system calculated by using the simulation tool from NREL, and hydrogen permeation rates for stainless steel and carbon steel grades taken from literature have been added to the model. In a first step the effect of HTF ageing, build-up of hydrogen pressure in the HTF and hydrogen loss rates through piping and receiver components have been modeled. In a second step a selective hydrogen removal process has been added to the model. The simulation results are confirming the need of active monitoring and controlling the effective hydrogen partial pressure in parabolic trough solar thermal power plants with DPO/BP HTF. Following the results of the simulation, the expected plant performance can only be achieved

  8. Gravity, chromosomes, and organized development in aseptically cultured plant cells

    NASA Technical Reports Server (NTRS)

    Krikorian, Abraham D.

    1993-01-01

    The objectives of the PCR experiment are: to test the hypothesis that microgravity will in fact affect the pattern and developmental progression of embryogenically competent plant cells from one well-defined, critical stage to another; to determine the effects of microgravity in growth and differentiation of embryogenic carrot cells grown in cell culture; to determine whether microgravity or the space environment fosters an instability of the differentiated state; and to determine whether mitosis and chromosome behavior are adversely affected by microgravity. The methods employed will consist of the following: special embryogenically competent carrot cell cultures will be grown in cell culture chambers provided by NASDA; four cell culture chambers will be used to grow cells in liquid medium; two dishes (plant cell culture dishes) will be used to grow cells on a semi-solid agar support; progression to later embryonic stages will be induced in space via crew intervention and by media manipulation in the case of liquid grown cell cultures; progression to later stages in case of semi-solid cultures will not need crew intervention; embryo stages will be fixed at a specific interval (day 6) in flight only in the case of liquid-grown cultures; and some living cells and somatic embryos will be returned for continued post-flight development and 'grown-out.' These will derive from the semi-solid grown cultures.

  9. Health Maintenance Organizations and the Elderly: Promises, Problems and Prospects. Hearing before the Select Committee on Aging. House of Representatives, Ninety-Ninth Congress, Second Session (Boynton Beach and Margate, FL). Part II.

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. House Select Committee on Aging.

    This document contains witness testimonies and prepared statements from the Congressional hearing to examine the efficiency of health maintenance organizations (HMOs) in providing medical care to the elderly. Opening statements are given by Congressmen Mica and Boucher. The hearing is organized into a morning and afternoon session with each…

  10. Plant-Associated Bacterial Degradation of Toxic Organic Compounds in Soil

    PubMed Central

    McGuinness, Martina; Dowling, David

    2009-01-01

    A number of toxic synthetic organic compounds can contaminate environmental soil through either local (e.g., industrial) or diffuse (e.g., agricultural) contamination. Increased levels of these toxic organic compounds in the environment have been associated with human health risks including cancer. Plant-associated bacteria, such as endophytic bacteria (non-pathogenic bacteria that occur naturally in plants) and rhizospheric bacteria (bacteria that live on and near the roots of plants), have been shown to contribute to biodegradation of toxic organic compounds in contaminated soil and could have potential for improving phytoremediation. Endophytic and rhizospheric bacterial degradation of toxic organic compounds (either naturally occurring or genetically enhanced) in contaminated soil in the environment could have positive implications for human health worldwide and is the subject of this review. PMID:19742157

  11. Maintenance or Collapse: Responses of Extraplastidic Membrane Lipid Composition to Desiccation in the Resurrection Plant Paraisometrum mileense

    PubMed Central

    Yu, Buzhu; Yu, Xiaomei; Li, Weiqi

    2014-01-01

    Resurrection plants usually grow in specific or extreme habitats and have the capacity to survive almost complete water loss. We characterized the physiological and biochemical responses of Paraisometrum mileense to extreme desiccation and found that it is a resurrection plant. We profiled the changes in lipid molecular species during dehydration and rehydration in P. mileense, and compared these with corresponding changes in the desiccation-sensitive plant Arabidopsis thaliana. One day of desiccation was lethal for A. thaliana but not for P. mileense. After desiccation and subsequent rewatering, A. thaliana showed dramatic lipid degradation accompanied by large increases in levels of phosphatidic acid (PA) and diacylglycerol (DAG). In contrast, desiccation and rewatering of P. mileense significantly decreased the level of monogalactosyldiacylglycerol and increased the unsaturation of membrane lipids, without changing the level of extraplastidic lipids. Lethal desiccation in P. mileense caused massive lipid degradation, whereas the PA content remained at a low level similar to that of fresh leaves. Neither damage nor repair processes, nor increases in PA, occurred during non-lethal desiccation in P. mileense. The activity of phospholipase D, the main source of PA, was much lower in P. mileense than in A. thaliana under control conditions, or after either dehydration or rehydration. It was demonstrated that low rates of phospholipase D-mediated PA formation in P. mileense might limit its ability to degrade lipids to PA, thereby maintaining membrane integrity following desiccation. PMID:25068901

  12. Hierarchical Helical Order in the Twisted Growth of Plant Organs

    NASA Astrophysics Data System (ADS)

    Wada, Hirofumi

    2012-09-01

    The molecular and cellular basis of left-right asymmetry in plant morphogenesis is a fundamental issue in biology. A rapidly elongating root or hypocotyl of twisting mutants of Arabidopsis thaliana exhibits a helical growth with a handedness opposite to that of the underlying cortical microtubule arrays in epidermal cells. However, how such a hierarchical helical order emerges is currently unknown. We propose a model for investigating macroscopic chiral asymmetry in Arabidopsis mutants. Our elastic model suggests that the helical pattern observed is a direct consequence of the simultaneous presence of anisotropic growth and tilting of cortical microtubule arrays. We predict that the root helical pitch angle is a function of the microtubule helical angle and elastic moduli of the tissues. The proposed model is versatile and is potentially important for other biological systems ranging from protein fibrous structures to tree trunks.

  13. Risk-based maintenance modeling. Prioritization of maintenance importances and quantification of maintenance effectiveness

    SciTech Connect

    Vesely, W.E.; Rezos, J.T.

    1995-09-01

    This report describes methods for prioritizing the risk importances of maintenances using a Probabilistic Risk Assessment (PRA). Approaches then are described for quantifying their reliability and risk effects. Two different PRA importance measures, minimal cutset importances and risk reduction importances, were used to prioritize maintenances; the findings show that both give similar results if appropriate criteria are used. The justifications for the particular importance measures also are developed. The methods developed to quantify the reliability and risk effects of maintenance actions are extensions of the usual reliability models now used in PRAs. These extended models consider degraded states of the component, and quantify the benefits of maintenance in correcting degradations and preventing failures. The negative effects of maintenance, including downtimes, also are included. These models are specific types of Markov models. The data for these models can be obtained from plant maintenance logs and from the Nuclear Plant Reliability Data System (NPRDS). To explore the potential usefulness of these models, the authors analyzed a range of postulated values of input data. These models were used to examine maintenance effects on a components reliability and performance for various maintenance programs and component data. Maintenance schedules were analyzed to optimize the component`s availability. In specific cases, the effects of maintenance were found to be large.

  14. Contributions of host cellular trafficking and organization to the outcomes of plant-pathogen interactions.

    PubMed

    Underwood, William

    2016-08-01

    In recent years it has become increasingly apparent that dynamic changes in protein localization, membrane trafficking pathways, and cellular organization play a major role in determining the outcome of interactions between plants and pathogenic microorganisms. Plants have evolved sophisticated perception systems to recognize the presence of potentially pathogenic microorganisms via the detection of non-self or modified-self elicitor molecules, pathogen virulence factors, or the activities of such virulence factors. Dynamic changes to host cellular organization and membrane trafficking pathways play pivotal roles in detection and signaling by plant immune receptors and are vital for the execution of spatially targeted defense responses to thwart invasion by potential pathogens. Conversely, from the perspective of the pathogen, the ability to manipulate plant cellular organization and trafficking processes to establish infection structures and deliver virulence factors is a major determinant of pathogen success. This review summarizes selected topics that illustrate how dynamic changes in host cellular trafficking and organization shape the outcomes of diverse plant-pathogen interactions and addresses ways in which our rapidly expanding knowledge of the cell biological processes that contribute to immunity or infection may influence efforts to improve plant disease resistance. PMID:27216829

  15. Temporal Control of Plant Organ Growth by TCP Transcription Factors.

    PubMed

    Huang, Tengbo; Irish, Vivian F

    2015-06-29

    The Arabidopsis petal is a simple laminar organ whose development is largely impervious to environmental effects, making it an excellent model for dissecting the regulation of cell-cycle progression and post-mitotic cell expansion that together sculpt organ form. Arabidopsis petals grow via basipetal waves of cell division, followed by a phase of cell expansion. RABBIT EARS (RBE) encodes a C2H2 zinc finger transcriptional repressor and is required for petal development. During the early phase of petal initiation, RBE regulates a microRNA164-dependent pathway that controls cell proliferation at the petal primordium boundaries. The effects of rbe mutations on petal lamina growth suggest that RBE is also required to regulate later developmental events during petal organogenesis. Here, we demonstrate that, early in petal development, RBE represses the transcription of a suite of CIN-TCP genes that in turn act to inhibit the number and duration of cell divisions; the temporal alleviation of that repression results in the transition from cell division to post-mitotic cell expansion and concomitant petal maturation. PMID:26073137

  16. Colonization of plants by human pathogenic bacteria in the course of organic vegetable production.

    PubMed

    Hofmann, Andreas; Fischer, Doreen; Hartmann, Anton; Schmid, Michael

    2014-01-01

    In recent years, increasing numbers of outbreaks caused by the consumption of vegetables contaminated with human pathogenic bacteria were reported. The application of organic fertilizers during vegetable production is one of the possible reasons for contamination with those pathogens. In this study laboratory experiments in axenic and soil systems following common practices in organic farming were conducted to identify the minimal dose needed for bacterial colonization of plants and to identify possible factors like bacterial species or serovariation, plant species or organic fertilizer types used, influencing the success of plant colonization by human pathogenic bacteria. Spinach and corn salad were chosen as model plants and were inoculated with different concentrations of Salmonella enterica sv. Weltevreden, Listeria monocytogenes sv. 4b and EGD-E sv. 1/2a either directly (axenic system) or via agricultural soil amended with spiked organic fertilizers (soil system). In addition to PCR- and culture-based detection methods, fluorescence in situ hybridization (FISH) was applied in order to localize bacteria on or in plant tissues. Our results demonstrate that shoots were colonized by the pathogenic bacteria at inoculation doses as low as 4 × 10 CFU/ml in the axenic system or 4 × 10(5) CFU/g in the soil system. In addition, plant species dependent effects were observed. Spinach was colonized more often and at lower inoculation doses compared to corn salad. Differential colonization sites on roots, depending on the plant species could be detected using FISH-CLSM analysis. Furthermore, the transfer of pathogenic bacteria to plants via organic fertilizers was observed more often and at lower initial inoculation doses when fertilization was performed with inoculated slurry compared to inoculated manure. Finally, it could be shown that by introducing a simple washing step, the bacterial contamination was reduced in most cases or even was removed completely in some

  17. Organic Farming and Landscape Structure: Effects on Insect-Pollinated Plant Diversity in Intensively Managed Grasslands

    PubMed Central

    Power, Eileen F.; Kelly, Daniel L.; Stout, Jane C.

    2012-01-01

    Parallel declines in insect-pollinated plants and their pollinators have been reported as a result of agricultural intensification. Intensive arable plant communities have previously been shown to contain higher proportions of self-pollinated plants compared to natural or semi-natural plant communities. Though intensive grasslands are widespread, it is not known whether they show similar patterns to arable systems nor whether local and/or landscape factors are influential. We investigated plant community composition in 10 pairs of organic and conventional dairy farms across Ireland in relation to the local and landscape context. Relationships between plant groups and local factors (farming system, position in field and soil parameters) and landscape factors (e.g. landscape complexity) were investigated. The percentage cover of unimproved grassland was used as an inverse predictor of landscape complexity, as it was negatively correlated with habitat-type diversity. Intensive grasslands (organic and conventional) contained more insect-pollinated forbs than non-insect pollinated forbs. Organic field centres contained more insect-pollinated forbs than conventional field centres. Insect-pollinated forb richness in field edges (but not field centres) increased with increasing landscape complexity (% unimproved grassland) within 1, 3, 4 and 5km radii around sites, whereas non-insect pollinated forb richness was unrelated to landscape complexity. Pollination systems within intensive grassland communities may be different from those in arable systems. Our results indicate that organic management increases plant richness in field centres, but that landscape complexity exerts strong influences in both organic and conventional field edges. Insect-pollinated forb richness, unlike that for non-insect pollinated forbs, showed positive relationships to landscape complexity reflecting what has been documented for bees and other pollinators. The insect-pollinated forbs, their

  18. Colonization of plants by human pathogenic bacteria in the course of organic vegetable production

    PubMed Central

    Hofmann, Andreas; Fischer, Doreen; Hartmann, Anton; Schmid, Michael

    2014-01-01

    In recent years, increasing numbers of outbreaks caused by the consumption of vegetables contaminated with human pathogenic bacteria were reported. The application of organic fertilizers during vegetable production is one of the possible reasons for contamination with those pathogens. In this study laboratory experiments in axenic and soil systems following common practices in organic farming were conducted to identify the minimal dose needed for bacterial colonization of plants and to identify possible factors like bacterial species or serovariation, plant species or organic fertilizer types used, influencing the success of plant colonization by human pathogenic bacteria. Spinach and corn salad were chosen as model plants and were inoculated with different concentrations of Salmonella enterica sv. Weltevreden, Listeria monocytogenes sv. 4b and EGD-E sv. 1/2a either directly (axenic system) or via agricultural soil amended with spiked organic fertilizers (soil system). In addition to PCR- and culture-based detection methods, fluorescence in situ hybridization (FISH) was applied in order to localize bacteria on or in plant tissues. Our results demonstrate that shoots were colonized by the pathogenic bacteria at inoculation doses as low as 4 × 10 CFU/ml in the axenic system or 4 × 105 CFU/g in the soil system. In addition, plant species dependent effects were observed. Spinach was colonized more often and at lower inoculation doses compared to corn salad. Differential colonization sites on roots, depending on the plant species could be detected using FISH-CLSM analysis. Furthermore, the transfer of pathogenic bacteria to plants via organic fertilizers was observed more often and at lower initial inoculation doses when fertilization was performed with inoculated slurry compared to inoculated manure. Finally, it could be shown that by introducing a simple washing step, the bacterial contamination was reduced in most cases or even was removed completely in some cases

  19. 42 CFR 476.72 - Review of the quality of care of risk-basis health maintenance organizations and competitive...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... disclosure of peer review information; and (2) Part 1004 of Chapter V regarding a QIO's responsibilities, and... 42 Public Health 4 2010-10-01 2010-10-01 false Review of the quality of care of risk-basis health... ORGANIZATIONS UTILIZATION AND QUALITY CONTROL REVIEW Review Responsibilities of Utilization and Quality...

  20. 42 CFR 476.72 - Review of the quality of care of risk-basis health maintenance organizations and competitive...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... disclosure of peer review information; and (2) Part 1004 of Chapter V regarding a QIO's responsibilities, and... 42 Public Health 4 2012-10-01 2012-10-01 false Review of the quality of care of risk-basis health... ORGANIZATIONS UTILIZATION AND QUALITY CONTROL REVIEW Review Responsibilities of Utilization and Quality...

  1. 42 CFR 476.72 - Review of the quality of care of risk-basis health maintenance organizations and competitive...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) QUALITY IMPROVEMENT... Quality Improvement Organizations (QIOs) General Provisions § 476.72 Review of the quality of care of risk... 42 Public Health 4 2011-10-01 2011-10-01 false Review of the quality of care of risk-basis...

  2. Bioremediation of polluted soil through the combined application of plants, earthworms and organic matter.

    PubMed

    Macci, Cristina; Doni, Serena; Peruzzi, Eleonora; Ceccanti, Brunello; Masciandaro, Grazia

    2012-10-26

    Two plant species (Paulownia tomentosa and Cytisus scoparius), earthworms (Eisenia fetida), and organic matter (horse manure) were used as an ecological approach to bioremediate a soil historically contaminated by heavy metals and hydrocarbons. The experiment was carried out for six months at a mesoscale level using pots containing 90 kg of polluted soil. Three different treatments were performed for each plant: (i) untreated planted soil as a control (C); (ii) planted soil + horse manure (20:1 w/w) (M); (iii) planted soil + horse manure + 15 earthworms (ME). Both the plant species were able to grow in the polluted soil and to improve the soil's bio-chemical conditions, especially when organic matter and earthworms were applied. By comparing the two plant species, few significant differences were observed in the soil characteristics; Cytisus scoparius improved soil nutrient content more than Paulownia tomentosa, which instead stimulated more soil microbial metabolism. Regarding the pollutants, Paulownia tomentosa was more efficient in reducing the heavy metal (Pb, Cr, Cd, Zn, Cu, Ni) content, while earthworms were particularly able to stimulate the processes involved in the decontamination of organic pollutants (hydrocarbons). This ecological approach, validated at a mesoscale level, has recently been transferred to a real scale situation to carry out the bioremediation of polluted soil in San Giuliano Terme Municipality (Pisa, Italy). PMID:22911348

  3. Positive regulation of minichromosome maintenance gene expression, DNA replication, and cell transformation by a plant retinoblastoma gene

    PubMed Central

    Sabelli, Paolo A.; Hoerster, George; Lizarraga, Lucina E.; Brown, Sara W.; Gordon-Kamm, William J.; Larkins, Brian A.

    2009-01-01

    Retinoblastoma-related (RBR) genes inhibit the cell cycle primarily by repressing adenovirus E2 promoter binding factor (E2F) transcription factors, which drive the expression of numerous genes required for DNA synthesis and cell cycle progression. The RBR-E2F pathway is conserved in plants, but cereals such as maize are characterized by having a complex RBR gene family with at least 2 functionally distinct members, RBR1 and RBR3. Although RBR1 has a clear cell cycle inhibitory function, it is not known whether RBR3 has a positive or negative role. By uncoupling RBR3 from the negative regulation of RBR1 in cultured maize embryos through a combination of approaches, we demonstrate that RBR3 has a positive and critical role in the expression of E2F targets required for the initiation of DNA synthesis, DNA replication, and the efficiency with which transformed plants can be obtained. Titration of endogenous RBR3 activity through expression of a dominant-negative allele with a compromised pocket domain suggests that these RBR3 functions require an activity distinct from its pocket domain. Our results indicate a cell cycle pathway in maize, in which 2 RBR genes have specific and opposing functions. Thus, the paradigm that RBR genes are negative cell cycle regulators cannot be considered universal. PMID:19234120

  4. Organic-inorganic hybrids from renewable plant oils and clay.

    PubMed

    Uyama, Hiroshi; Kuwabara, Mai; Tsujimoto, Takashi; Nakano, Mitsuru; Usuki, Arimitsu; Kobayashi, Shiro

    2004-03-15

    This study deals with the preparation and properties of a new class of organic-inorganic hybrids from renewable resources. The hybrids were synthesized by an acid-catalyzed curing of epoxidized triglycerides in the presence of an organophilic montmorillonite (a modified clay). The mechanical properties were improved by the incorporation of clay in the oil-based polymer matrix. The reinforcement effect due to the addition of clay was confirmed by dynamic viscoelasticity analysis. The hybrids showed relatively high thermal stability. The co-curing of epoxidized soybean and linseed oils in the presence of clay produced hybrids with controlled mechanical and coating properties. The barrier property of the hybrid towards water vapor was superior to that of the oil polymer. The development of the present hybrids consisting of inexpensive renewable resources, triglyceride and clay is expected to contribute to global sustainability. PMID:15468227

  5. Calcium and Calmodulin Localization in Gravitropically-responding Plant Organs

    NASA Technical Reports Server (NTRS)

    Roux, S. J.

    1985-01-01

    Antimonate staining procedures were used to detect calcium redistribution changes in corn roots. Results show that an asymmetric redistribution of Ca is induced by a gravitropic stimulus in roots as it is in shoots. Since this response occurs within 10 min, at least 5 min before any visible bending, it could play a role in the regulation of root gravitropism. Two different general approaches were used to localize calmodulin in plant tissue: radioimmunoassay of its content in tissue and in purified subcellular organelles, and immunocytochemical detection of it in roots and coleoptiles. Radioimmunoassay results indicate that calmodulin is present in large quantities in pllant cells and that it is specifically associated with mitochondria, etioplasts and nuclei. An assayed of an extract of soluble wall proteins revealed that over 1% of these proteins was calmodulin. Controls indicate that this calmodulin is not cytoplasmic in origin. A reaction product from anti-calmodulin was found mainly in the root cap cells, moderately in metazylem elements, in some cells in the stele surrounding metaxylem elements and in cortical cells.

  6. Treatment of hydroponic wastewater by denitrification filters using plant prunings as the organic carbon source.

    PubMed

    Park, J B K; Craggs, R J; Sukias, J P S

    2008-05-01

    This study investigated the feasibility of using pre-treated plant liquors as organic carbon sources for the treatment of hydroponic wastewater containing high nitrate-N (>300 mg N/L). The waste plant material was pre-treated to extract organic carbon-rich liquors. When this plant liquor was used as an organic carbon source in denitrification filters at the organic carbon:nitrogen dose rate of 3C:N, nitrate removal efficiencies were >95% and final effluent nitrate concentrations were consistently <20mg N/L. However, at this dose rate, relatively high concentrations (>140 mg/L) of organic carbon (fBOD5) remained in the final effluents. Therefore, a 'compromise' organic carbon:nitrogen dose rate (2C:N) was trialled, at which nitrate removal efficiencies were maintained at >85%, final effluent nitrate concentrations were consistently below 45 mg N/L, and effluent fBOD5 concentrations were <25mg/L. This study has demonstrated that waste plant material is a suitable carbon source for the removal of nitrate from hydroponic wastewater in a denitrification filter. PMID:17714940

  7. Maintenance of the Cardiovascular Function in a Deeply Cooled Homeothermic Organism by Physiological Methods without External Rewarming.

    PubMed

    Ivanov, K P; Arokina, N K

    2016-02-01

    Gradual cooling of homeothermic organisms is followed by slowing and arrest of breathing and heart contractions. During deep cooling, even relatively slight artificial ventilation decreases the lower temperature limit of life (by 4.5-5°C) and provides minimum oxygen supply to the heart and whole body. This allows us to restore cardiovascular function and prevent animal death after lethal cooling without eternal warming. PMID:26902347

  8. Home Maintenance Manual.

    ERIC Educational Resources Information Center

    Richmond, Jim; And Others

    This manual, written especially for the Navajo and Hopi Indian Relocation Commission, is a simply worded, step-by-step guide to home maintenance for new homeowners. It can be used for self-study or it can serve as instructional material for a training class on home ownership. The manual is organized in nine sections that cover the following…

  9. Industrial Mechanical Maintenance.

    ERIC Educational Resources Information Center

    Hendrix, Laborn J.

    This manual was developed to assist teachers in Oklahoma in preparing students for industrial mechanical maintenance. The materials in this teacher's guide are organized in 14 units of instruction covering the following four areas: receiving and setting equipment; equipment hookup and operation; equipment layout, anchoring, and setup; and…

  10. Stitching Organelles: Organization and Function of Specialized Membrane Contact Sites in Plants.

    PubMed

    Pérez-Sancho, Jessica; Tilsner, Jens; Samuels, A Lacey; Botella, Miguel A; Bayer, Emmanuelle M; Rosado, Abel

    2016-09-01

    The coordination of multiple metabolic activities in plants relies on an interorganelle communication network established through membrane contact sites (MCS). The MCS are maintained in transient or durable configurations by tethering structures which keep the two membranes in close proximity, and create chemical microdomains that allow localized and targeted exchange of small molecules and possibly proteins. The past few years have witnessed a dramatic increase in our understanding of the structural and molecular organization of plant interorganelle MCS, and their crucial roles in plant specialized functions including stress responses, cell to cell communication, and lipid transport. In this review we summarize recent advances in understanding the molecular components, structural organization, and functions of different plant-specific MCS architectures. PMID:27318776

  11. Organ-specific regulation of growth-defense tradeoffs by plants.

    PubMed

    Smakowska, Elwira; Kong, Jixiang; Busch, Wolfgang; Belkhadir, Youssef

    2016-02-01

    Plants grow while also defending themselves against phylogenetically unrelated pathogens. Because defense and growth are both costly programs, a plant's success in colonizing resource-scarce environments requires tradeoffs between the two. Here, we summarize efforts aimed at understanding how plants use iterative tradeoffs to modulate differential organ growth when defenses are elicited. First, we focus on shoots to illustrate how light, in conjunction with the growth hormone gibberellin (GA) and the defense hormone jasmonic acid (JA), act to finely regulate defense and growth programs in this organ. Second, we expand on the regulation of growth-defense trade-offs in the root, a less well-studied topic despite the critical role of this organ in acquiring resources in an environment deeply entrenched with disparate populations of microbes. PMID:26802804

  12. Demonstration of the use of ADAPT to derive predictive maintenance algorithms for the KSC central heat plant

    NASA Technical Reports Server (NTRS)

    Hunter, H. E.

    1972-01-01

    The Avco Data Analysis and Prediction Techniques (ADAPT) were employed to determine laws capable of detecting failures in a heat plant up to three days in advance of the occurrence of the failure. The projected performance of algorithms yielded a detection probability of 90% with false alarm rates of the order of 1 per year for a sample rate of 1 per day with each detection, followed by 3 hourly samplings. This performance was verified on 173 independent test cases. The program also demonstrated diagnostic algorithms and the ability to predict the time of failure to approximately plus or minus 8 hours up to three days in advance of the failure. The ADAPT programs produce simple algorithms which have a unique possibility of a relatively low cost updating procedure. The algorithms were implemented on general purpose computers at Kennedy Space Flight Center and tested against current data.

  13. Mechanisms of Heavy Metal Sequestration in Soils: Plant-Microbe Interactions and Organic Matter Aging

    SciTech Connect

    Teresa W.-M. Fan; Richard M. Higashi; David Crowley; Andrew N. Lane: Teresa A. Cassel; Peter G. Green

    2004-12-31

    For stabilization of heavy metals at contaminated sites, the three way interaction among soil organic matter (OM)-microbes-plants, and their effect on heavy metal binding is critically important for long-term sustainability, a factor that is poorly understood at the molecular level. Using a soil aging system, the humification of plant matter such as wheat straw was probed along with the effect on microbial community on soil from the former McClellan Air Force Base.

  14. Differential effect of plant lipids on membrane organization: specificities of phytosphingolipids and phytosterols.

    PubMed

    Grosjean, Kevin; Mongrand, Sébastien; Beney, Laurent; Simon-Plas, Françoise; Gerbeau-Pissot, Patricia

    2015-02-27

    The high diversity of the plant lipid mixture raises the question of their respective involvement in the definition of membrane organization. This is particularly the case for plant plasma membrane, which is enriched in specific lipids, such as free and conjugated forms of phytosterols and typical phytosphingolipids, such as glycosylinositolphosphoceramides. This question was here addressed extensively by characterizing the order level of membrane from vesicles prepared using various plant lipid mixtures and labeled with an environment-sensitive probe. Fluorescence spectroscopy experiments showed that among major phytosterols, campesterol exhibits a stronger ability than β-sitosterol and stigmasterol to order model membranes. Multispectral confocal microscopy, allowing spatial analysis of membrane organization, demonstrated accordingly the strong ability of campesterol to promote ordered domain formation and to organize their spatial distribution at the membrane surface. Conjugated sterol forms, alone and in synergy with free sterols, exhibit a striking ability to order membrane. Plant sphingolipids, particularly glycosylinositolphosphoceramides, enhanced the sterol-induced ordering effect, emphasizing the formation and increasing the size of sterol-dependent ordered domains. Altogether, our results support a differential involvement of free and conjugated phytosterols in the formation of ordered domains and suggest that the diversity of plant lipids, allowing various local combinations of lipid species, could be a major contributor to membrane organization in particular through the formation of sphingolipid-sterol interacting domains. PMID:25575593

  15. Duration of emission of volatile organic compounds from mechanically damaged plant leaves.

    PubMed

    Smith, Lincoln; Beck, John J

    2015-09-01

    Classical biological control of invasive alien weeds depends on the use of arthropod herbivores that are sufficiently host specific to avoid risk of injuring nontarget plants. Host plant specificity is usually evaluated by using a combination of behavioral and developmental experiments under choice, no-choice and field conditions. Secondary plant compounds are likely to have an important influence on host plant specificity. However, relatively little is known about the volatile organic compounds (VOCs) that are emitted by target and nontarget plants, and how environmental conditions may affect their emission. Previous studies have shown that mechanical damage of leaves increases the composition and content of VOCs emitted. In this study we measured the VOC emissions of five species of plants in the subtribe Centaureinae (Asteraceae)--Carthamus tinctorius, Centaurea cineraria, Centaurea melitensis, Centaurea rothrockii, and Centaurea solstitialis--that have previously been used in host specificity experiments for a prospective biological control agent of yellow starthistle (C. solstitialis). Leaves of each plant were punctured with a needle and the VOCs were collected by solid-phase microextraction (SPME) periodically over 48 h and analyzed by GC-MS. A total of 49 compounds were detected. Damage caused an immediate increase of 200-600% in the composition of VOCs emitted from each plant species, and the amounts generally remained high for at least 48 h. The results indicate that a very unspecific mechanical damage can cause a prolonged change in the VOC profile of plants. PMID:26398629

  16. Efficient CO2 Fixation Pathways: Energy Plant: High Efficiency Photosynthetic Organisms

    SciTech Connect

    2012-01-01

    PETRO Project: UCLA is redesigning the carbon fixation pathways of plants to make them more efficient at capturing the energy in sunlight. Carbon fixation is the key process that plants use to convert carbon dioxide (CO2) from the atmosphere into higher energy molecules (such as sugars) using energy from the sun. UCLA is addressing the inefficiency of the process through an alternative biochemical pathway that uses 50% less energy than the pathway used by all land plants. In addition, instead of producing sugars, UCLA’s designer pathway will produce pyruvate, the precursor of choice for a wide variety of liquid fuels. Theoretically, the new biochemical pathway will allow a plant to capture 200% as much CO2 using the same amount of light. The pathways will first be tested on model photosynthetic organisms and later incorporated into other plants, thus dramatically improving the productivity of both food and fuel crops.

  17. Detection, Composition and Treatment of Volatile Organic Compounds from Waste Treatment Plants

    PubMed Central

    Font, Xavier; Artola, Adriana; Sánchez, Antoni

    2011-01-01

    Environmental policies at the European and global level support the diversion of wastes from landfills for their treatment in different facilities. Organic waste is mainly treated or valorized through composting, anaerobic digestion or a combination of both treatments. Thus, there are an increasing number of waste treatment plants using this type of biological treatment. During waste handling and biological decomposition steps a number of gaseous compounds are generated or removed from the organic matrix and emitted. Different families of Volatile Organic Compounds (VOC) can be found in these emissions. Many of these compounds are also sources of odor nuisance. In fact, odors are the main source of complaints and social impacts of any waste treatment plant. This work presents a summary of the main types of VOC emitted in organic waste treatment facilities and the methods used to detect and quantify these compounds, together with the treatment methods applied to gaseous emissions commonly used in composting and anaerobic digestion facilities. PMID:22163835

  18. Effect of organic amendments and mineral fertilizer on zinc bioavailability, plant content and translocation

    NASA Astrophysics Data System (ADS)

    Chami, Ziad Al; Cavoski, Ivana; Mondelli, Donato; Miano, Teodoro

    2013-04-01

    Organic matter plays a key role in heavy metal bioavailability through changes in soil chemical characteristics, and by its metal-chelating ability, the latter being one of the most important factors controlling the mobility and bioavailability of heavy metals in the soil-plant system. In this research, rocket (Eruca vesicaria L. Cavalieri), a common edible plant species in the Mediterranean regions, was used as bio-indicator to evaluate the effect of different organic amendments on Zn toxicity, absorption, and translocation. The main objectives of this study were to investigate the bioavailability of Zn in an artificially contaminated soil after the addition of compost, manure and chemical fertilizers at agronomically recommended doses and to evaluate their ability to reduce Zn concentration in the edible plant part. A greenhouse pots experiment was carried out using rocket plant grown on an artificially contaminated soil. In this study, the effect of compost, manure and chemical fertilizers on Zn fate in a soil-plant system was evaluated. At the end of the experiment main growth parameters and Zn content in plants were determined. In addition, Zn speciation in the soil was assessed using the original BCR sequential extraction and the DTPA extraction. The overall assessment of experimental results is that compost, followed by chemical fertilizers treatments, was the most efficient in enhancing plant growth and decreasing metal toxicity and concentrations in plant tissues. Manure amendments increased plant Zn content and toxicity in rocket plants. In the case of compost treatment, this effect can be attributed to the humified OM present in compost; while the negative effect of manure is due to its content in low molecular weight organic acids. The effect of chemical fertilizers treatment could be attributed to the addition of P fertilizer in soluble and highly available forms to the plants. On the contrary, using DTPA and BCR sequential extraction procedure, all

  19. Safety evaluation for packaging for onsite transfer of B Plant organic waste

    SciTech Connect

    Mercado, M.S.

    1996-10-07

    This safety evaluation for packaging authorizes the use of a 17,500-L (4,623-gal) tank manufactured by Brenner Tank, Incorporated, to transport up to 16,221 L (4,285 gal) of radioactive organic liquid waste. The waste will be transported from the organic loading pad to a storage pad. Both pads are within the B Plant complex, but approximately 4 mi apart.

  20. A novel analytical approach for visualizing and tracking organic chemicals in plants.

    PubMed

    Wild, Edward; Dent, John; Barber, Jonathan L; Thomas, Gareth O; Jones, Kevin C

    2004-08-01

    Vegetation plays a key role in the environmental fate of many organic chemicals, from pesticides applied to plants, to the air-vegetation exchange and global cycling of atmospheric organic contaminants. Our ability to locate such compounds in plants has traditionally relied on inferences being made from destructive chemical extraction techniques or methods with potential artifacts. Here, for the first time, two-photon excitation microscopy (TPEM) is coupled with plant autofluorescence to visualize and track trace levels of an organic contaminant in living plant tissue, without any form of sample modification or manipulation. Anthracene-a polynuclear aromatic hydrocarbon (PAH)-was selected for study in living maize (Zea mays) leaves. Anthracene was tracked over 96 h, where amounts as low as approximately 0.1-10 pg were visible, as it moved through the epicuticular wax and plant cuticle, and was observed reaching the cytoplasm of the epidermal cells. By this stage, anthracene was identifiable in five separate locations within the leaf: (1) as a thin (approximately 5 microm) diffuse layer, in the upper surface of the epicuticular wax; (2) as thick (approximately 28 microm) diffuse bands extending from the epicuticular wax through the cuticle, to the cell walls of the epidermal cells; (3) on the external surface of epidermal cell walls; (4) on the internal surface of epidermal cell walls; and (5) within the cytoplasm of the epidermal cells. This technique provides a powerful nonintrusive tool for visualizing and tracking the movement, storage locations, and degradation of organic chemicals within vegetation using only plant and compound autofluorescence. Many other applications are envisaged for TPEM, in visualizing organic chemicals within different matrixes. PMID:15352460

  1. Subcellular Targeting of Methylmercury Lyase Enhances Its Specific Activity for Organic Mercury Detoxification in Plants1

    PubMed Central

    Bizily, Scott P.; Kim, Tehryung; Kandasamy, Muthugapatti K.; Meagher, Richard B.

    2003-01-01

    Methylmercury is an environmental pollutant that biomagnifies in the aquatic food chain with severe consequences for humans and other animals. In an effort to remove this toxin in situ, we have been engineering plants that express the bacterial mercury resistance enzymes organomercurial lyase MerB and mercuric ion reductase MerA. In vivo kinetics experiments suggest that the diffusion of hydrophobic organic mercury to MerB limits the rate of the coupled reaction with MerA (Bizily et al., 2000). To optimize reaction kinetics for organic mercury compounds, the merB gene was engineered to target MerB for accumulation in the endoplasmic reticulum and for secretion to the cell wall. Plants expressing the targeted MerB proteins and cytoplasmic MerA are highly resistant to organic mercury and degrade organic mercury at 10 to 70 times higher specific activity than plants with the cytoplasmically distributed wild-type MerB enzyme. MerB protein in endoplasmic reticulum-targeted plants appears to accumulate in large vesicular structures that can be visualized in immunolabeled plant cells. These results suggest that the toxic effects of organic mercury are focused in microenvironments of the secretory pathway, that these hydrophobic compartments provide more favorable reaction conditions for MerB activity, and that moderate increases in targeted MerB expression will lead to significant gains in detoxification. In summary, to maximize phytoremediation efficiency of hydrophobic pollutants in plants, it may be beneficial to target enzymes to specific subcellular environments. PMID:12586871

  2. Digital Single-Cell Analysis of Plant Organ Development Using 3DCellAtlas[OPEN

    PubMed Central

    Montenegro-Johnson, Thomas D.; Stamm, Petra; Strauss, Soeren; Topham, Alexander T.; Tsagris, Michail; Wood, Andrew T.A.; Smith, Richard S.; Bassel, George W.

    2015-01-01

    Diverse molecular networks underlying plant growth and development are rapidly being uncovered. Integrating these data into the spatial and temporal context of dynamic organ growth remains a technical challenge. We developed 3DCellAtlas, an integrative computational pipeline that semiautomatically identifies cell types and quantifies both 3D cellular anisotropy and reporter abundance at single-cell resolution across whole plant organs. Cell identification is no less than 97.8% accurate and does not require transgenic lineage markers or reference atlases. Cell positions within organs are defined using an internal indexing system generating cellular level organ atlases where data from multiple samples can be integrated. Using this approach, we quantified the organ-wide cell-type-specific 3D cellular anisotropy driving Arabidopsis thaliana hypocotyl elongation. The impact ethylene has on hypocotyl 3D cell anisotropy identified the preferential growth of endodermis in response to this hormone. The spatiotemporal dynamics of the endogenous DELLA protein RGA, expansin gene EXPA3, and cell expansion was quantified within distinct cell types of Arabidopsis roots. A significant regulatory relationship between RGA, EXPA3, and growth was present in the epidermis and endodermis. The use of single-cell analyses of plant development enables the dynamics of diverse regulatory networks to be integrated with 3D organ growth. PMID:25901089

  3. Privatizing Maintenance.

    ERIC Educational Resources Information Center

    Hounsell, Dan

    1996-01-01

    Schools and other government facilities want to see whether privatization of maintenance can provide services as efficiently and at less cost than inhouse workers. Privatization proponents say that everyone will benefit the most if the bidding process involves competition. Offers examples from the Memphis City Schools and the Union Public Schools…

  4. Microtubule dynamics of the centrosome-like polar organizers from the basal land plant Marchantia polymorpha.

    PubMed

    Buschmann, Henrik; Holtmannspötter, Michael; Borchers, Agnes; O'Donoghue, Martin-Timothy; Zachgo, Sabine

    2016-02-01

    The liverwort Marchantia employs both modern and ancestral devices during cell division: it forms preprophase bands and in addition it shows centrosome-like polar organizers. We investigated whether polar organizers and preprophase bands cooperate to set up the division plane. To this end, two novel green fluorescent protein-based microtubule markers for dividing cells of Marchantia were developed. Cells of the apical notch formed polar organizers first and subsequently assembled preprophase bands. Polar organizers were formed de novo from multiple mobile microtubule foci localizing to the nuclear envelope. The foci then became concentrated by bipolar aggregation. We determined the comet production rate of polar organizers and show that microtubule plus ends of astral microtubules polymerize faster than those found on cortical microtubules. Importantly, it was observed that conditions increasing polar organizer numbers interfere with preprophase band formation. The data show that polar organizers have much in common with centrosomes, but that they also have specialized features. The results suggest that polar organizers contribute to preprophase band formation and in this way are involved in controlling the division plane. Our analyses of the basal land plant Marchantia shed new light on the evolution of plant cell division. PMID:26467050

  5. DOH1, a Class 1 knox Gene, Is Required for Maintenance of the Basic Plant Architecture and Floral Transition in Orchid

    PubMed Central

    Yu, Hao; Yang, Shu Hua; Goh, Chong Jin

    2000-01-01

    We report here the isolation and identification of an orchid homeobox gene, DOH1, from Dendrobium Madame Thong-In. Analyses of its sequence and genomic organization suggest that DOH1 may be the only class 1 knox gene in the genome. DOH1 mRNA accumulates in meristem-rich tissues, and its expression is greatly downregulated during floral transition. In situ hybridization analysis demonstrates that DOH1 is also expressed in the incipient leaf primordia and is later detected in the same region of the inflorescence apex, as in DOMADS1. Overexpression of DOH1 in orchid plants completely suppresses shoot organization and development. Transgenic orchid plants expressing antisense mRNA for DOH1 show multiple shoot apical meristem (SAM) formations and early flowering. In addition, both the sense and antisense transformants exhibit defects in leaf development. These findings suggest that DOH1 plays a key role in maintaining the basic plant architecture of orchid through control of the formation and development of the SAM and shoot structure. Investigations of DOMADS1 expression in the SAM during floral transition reveal that the precocious flowering phenotype exhibited by DOH1 antisense transformants is coupled with the early onset of DOMADS1 expression. This fact, together with the reciprocal expression of DOH1 and DOMADS1 during floral transition, indicates that downregulation of DOH1 in the SAM is required for floral transition in orchid and that DOH1 is a possible upstream regulator of DOMADS1. PMID:11090215

  6. Plants mediate soil organic matter decomposition in response to sea level rise.

    PubMed

    Mueller, Peter; Jensen, Kai; Megonigal, James Patrick

    2016-01-01

    Tidal marshes have a large capacity for producing and storing organic matter, making their role in the global carbon budget disproportionate to land area. Most of the organic matter stored in these systems is in soils where it contributes 2-5 times more to surface accretion than an equal mass of minerals. Soil organic matter (SOM) sequestration is the primary process by which tidal marshes become perched high in the tidal frame, decreasing their vulnerability to accelerated relative sea level rise (RSLR). Plant growth responses to RSLR are well understood and represented in century-scale forecast models of soil surface elevation change. We understand far less about the response of SOM decomposition to accelerated RSLR. Here we quantified the effects of flooding depth and duration on SOM decomposition by exposing planted and unplanted field-based mesocosms to experimentally manipulated relative sea level over two consecutive growing seasons. SOM decomposition was quantified as CO2 efflux, with plant- and SOM-derived CO2 separated via δ(13) CO2 . Despite the dominant paradigm that decomposition rates are inversely related to flooding, SOM decomposition in the absence of plants was not sensitive to flooding depth and duration. The presence of plants had a dramatic effect on SOM decomposition, increasing SOM-derived CO2 flux by up to 267% and 125% (in 2012 and 2013, respectively) compared to unplanted controls in the two growing seasons. Furthermore, plant stimulation of SOM decomposition was strongly and positively related to plant biomass and in particular aboveground biomass. We conclude that SOM decomposition rates are not directly driven by relative sea level and its effect on oxygen diffusion through soil, but indirectly by plant responses to relative sea level. If this result applies more generally to tidal wetlands, it has important implications for models of SOM accumulation and surface elevation change in response to accelerated RSLR. PMID:26342160

  7. The Influence of Sound Cues on the Maintenance of Temporal Organization in the Sprague-Dawley Rat

    NASA Technical Reports Server (NTRS)

    Winget, C. M.; Moeller, K. A.; Holley, D. C.; Souza, Kenneth A. (Technical Monitor)

    1994-01-01

    Temporal organization is a fundamental property of living matter. From single cells to complex animals including man, most physiological systems undergo daily periodic changes in concert with environmental cues (e.g., light, temperature etc.). It is known that pulsed Environmental synchronizers, zeitgebers, (e.g. light) can modify rhythm parameters. Rhythm stability is a necessary requirement for most animal experiments. The extent to which sound can influence the circadian system of laboratory rats is poorly understood. This has implications to animal habitats in the novel environments of the Space-Laboratory or Space Station. A series of three white noise (88+/-0.82 db) zeitgeber experiments were conducted (n=6/experiment).The sound cue was introduced in the circadian free-running phase (DD-NQ) and in one additional case sound was added to the usual photoperiod (12L:12D) to determine masking effects. Circadian rhythm parameters of drinking frequency, feeding frequency, and gross locomotor activity were continuously monitored. Data analysis for these studies included macroscopic and microscopic methods. Raster plots to visually detect entrainment versus free-running period, were plotted for each animal, for all three parameters, during all sound perturbation tested. These data were processed through a series of detrending (robust locally weighted regression analyses) and complex demodulation analyses. In summary, these findings show that periodic "white" noise "influences" the rats circadian system but does not "entrain" the feeding, drinking or locomotor activity rhythms.

  8. Riverine Dissolved Organic Matter Degradation Modeled Through Microbial Incubations of Vascular Plant Leachates

    NASA Astrophysics Data System (ADS)

    Harfmann, J.; Hernes, P.; Chuang, C. Y.

    2015-12-01

    Dissolved organic matter (DOM) contains as much carbon as is in the atmosphere, provides the main link between terrestrial and marine carbon reservoirs, and fuels the microbial food web. The fate and removal of DOM is a result of several complex conditions and processes, including photodegradation, sorption/desorption, dominant vascular plant sources, and microbial abundance. In order to better constrain factors affecting microbial degradation, laboratory incubations were performed using Sacramento River water for microbial inoculums and vascular plant leachates. Four vascular plant sources were chosen based on their dominance in the Sacramento River Valley: gymnosperm needles from Pinus sabiniana (foothill pine), angiosperm dicot leaves from Quercus douglassi (blue oak), angiosperm monocot mixed annual grasses, and angiosperm monocot mixed Schoenoplectus acutus (tule) and Typha spp. (cattails). Three concentrations of microbial inoculum were used for each plant material, ranging from 0.2% to 10%. Degradation was monitored as a function of time using dissolved organic carbon (DOC), UV-Vis absorbance, and fluorescent dissolved organic matter (fDOM), and was compared across vascular plant type and inoculum concentration.

  9. Partition coefficient of cadmium between organic soils and bean and oat plants

    SciTech Connect

    Siddqui, M.F.R.; Courchesne, F.; Kennedy, G.; Zayed, J.

    1995-12-31

    Environmental fate models require the partition coefficient data of contaminants among two or more environmental compartments. The bioaccumulation of cadmium (Cd) by bean and oat plants grown on organic soils in a controlled growth chamber was investigated to validate the plant/soil partition coefficient. Total Cd was measured in the soils and in the different parts of the plants. The mean total Cd concentrations for soil cultivated with beans and oats were 0.86 and 0.69 {micro}g/g, respectively. Selective extractants (BaCl{sub 2}, Na-pyrophosphate and HNO{sub 3}-hydroxy) were used to evaluate solid phase Cd species in the soil. In the soil cultivated with bean, BaCl{sub 2} exchangeable, Na-pyrophosphate extractable and HNO{sub 3}-NH{sub 2}OH extractable Cd represented 1.2, 1.6 and 50.9% of total soil Cd, respectively. For the soil cultivated with oats, the same extractants gave values of 1.1, 1.8 and 61.9%. Cd concentration levels in bean plants followed the sequence roots > fruits = stems > leaves (p < 0.01) while the following sequence was observed for oat plants: roots > fruits > stems > leaves (p < 0.05). The partition coefficient for total Cd (Cd{sub Plant tissue}/Cd{sub Soil}) was in the range of 0.28--0.55 for bean plants and 1.03--1.86 for oat plants.

  10. A novel laboratory system for determining fate of volatile organic compounds in planted systems

    SciTech Connect

    Orchard, B.J.; Doucette, W.J.; Chard, J.K; Bugbee, B.

    2000-04-01

    Contradictory observations regarding the uptake and translocation of volatile organic compounds (VOCs) by plants have been reported, most notably for trichloroethylene (TCE). Experimental artifacts resulting from the use of semistatic or low-flow laboratory systems may account for part of the discrepancy. Innovative plant growth chambers are required to rigorously quantify the movement of VOCs through higher plants while maintaining a natural plant environment. The plant must be sealed in a chamber that allows rapid exchange of air to remove the water vapor lost in transpiration, to resupply the CO{sub 2} consumed in photosynthesis, and to resupply the O{sub 2} consumed in root-zone respiration. Inadequate airflow through the foliar region results in high humidity, which dramatically reduces transpiration and may reduce contaminant flux. Oxygen depletion in static root zones induces root stress, which can increase root membrane permeability. The root zone must be separated from the shoots to differentiate between plant uptake and foliar deposition. Here the authors describe the design, construction, and testing of a dual-vacuum, continuous high-flow chamber systems for accurately determining the fate of VOCs plants. The system provides a natural plant environment, complete root/shoot separation, the ability to quantify phytovolatilization and mineralization in both root and shoot compartments, continuous root-zone aeration, and high mass recovery.

  11. Promotion of plant growth by Pseudomonas fluorescens strain SS101 via novel volatile organic compounds.

    PubMed

    Park, Yong-Soon; Dutta, Swarnalee; Ann, Mina; Raaijmakers, Jos M; Park, Kyungseok

    2015-05-29

    Volatile organic compounds (VOCs) from plant growth-promoting rhizobacteria (PGPR) play key roles in modulating plant growth and induced systemic resistance (ISR) to pathogens. Despite their significance, the physiological functions of the specific VOCs produced by Pseudomonas fluorescens SS101 (Pf.SS101) have not been precisely elucidated. The effects of Pf.SS101 and its VOCs on augmentation of plant growth promotion were investigated in vitro and in planta. A significant growth promotion was observed in plants exposed Pf.SS101 under both conditions, suggesting that its VOCs play a key role in promoting plant growth. Solid-phase micro-extraction (SPME) and a gas chromatography-mass spectrophotometer (GC-MS) system were used to characterize the VOCs emitted by Pf.SS101 and 11 different compounds were detected in samples inoculated this bacterium, including 13-Tetradecadien-1-ol, 2-butanone and 2-Methyl-n-1-tridecene. Application of these compounds resulted in enhanced plant growth. This study suggests that Pf.SS101 promotes the growth of plants via the release of VOCs including 13-Tetradecadien-1-ol, 2-butanone and 2-Methyl-n-1-tridecene, thus increasing understanding of the role of VOCs in plant-bacterial inter-communication. PMID:25892516

  12. Plant roots alter microbial potential for mediation of soil organic carbon decomposition

    NASA Astrophysics Data System (ADS)

    Firestone, M.; Shi, S.; Herman, D.; He, Z.; Zhou, J.

    2014-12-01

    Plant root regulation of soil organic carbon (SOC) decomposition is a key controller of terrestrial C-cycling. Although many studies have tested possible mechanisms underlying plant "priming" of decomposition, few have investigated the microbial mediators of decomposition, which can be greatly influenced by plant activities. Here we examined effects of Avena fatua roots on decomposition of 13C-labeled root litter in a California grassland soil over two simulated growing-seasons. The presence of plant roots consistently suppressed rates of litter decomposition. Reduction of inorganic nitrogen (N) concentration in soil reduced but did not completely relieve this suppressive effect. The presence of plants significantly altered the abundance, composition and functional potential of microbial communities. Significantly higher signal intensities of genes capable of degrading low molecular weight organic compounds (e.g., glucose, formate and malate) were observed in microbial communities from planted soils, while microorganisms in unplanted soils had higher relative abundances of genes involved in degradation of some macromolecules (e.g., hemicellulose and lignin). Additionally, compared to unplanted soils, microbial communities from planted soils had higher signal intensities of proV and proW, suggesting microbial osmotic stress in planted soils. Possible mechanisms for the observed inhibition of decomposition are 1) microbes preferentially using simple substrates from root exudates and 2) soil drying by plant evapotranspiration impairing microbial activity. We propose a simple data-based model suggesting that the impacts of roots, the soil environment, and microbial community composition on decomposition processes result from impacts of these factors on the soil microbial functional gene potential.

  13. Organic blueberry production systems: management of plant nutrition, irrigation requirements, and weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A long-term systems trial was established to evaluate factorial management practices for organic production of highbush blueberry. The practices include: flat and raised planting beds; feather meal and fish emulsion fertilizer applied at 29 and 57 kg/ha N; sawdust mulch, compost topped with sawdust ...

  14. Cover crops and organic mulches for nematode, weed, and plant health management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two field experiments were conducted in 2003 and 2004 to evaluate ‘Tropic Sun’ sunn hemp (Crotalaria juncea) and ‘Iron Clay’ cowpea (Vigna unguiculata) as summer cover crops and as organic mulches. Both experiments were a 3 x 3 split-plot design in which the main plots were summer planting of sunn h...

  15. Organic blueberry production systems: management of plant nutrition, irrigation requirements, and weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A long-term systems trial was established to evaluate management practices for organic production of northern highbush blueberry (Vaccinium corymbosum L.). The factorial experiment included two planting bed treatments (flat and raised beds), source and rate of fertilizer (feather meal and fish emuls...

  16. CHARACTERIZATION OF MERCURY EMISSIONS AT A CHLOR-ALKALI PLANT: STUDY ORGANIZATION AND IMPLEMENTATION

    EPA Science Inventory

    The paper describes the organization and implementation of a detailed emissions measurement campaign conducted over a 2-week period at the Olin Corporation's mercury chlor-alkali plant in Augusta, GA. (NOTE: Since data analysis is continuing, study results will be provided later...

  17. Book Review: "The Rhizosphere: Biochemistry and Organic Substances at the Soil-Plant Interface, Second Edition"

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The complexity of the biological, chemical, and physical interactions occurring in the volume of soil surrounding the root of a growing plant dictates that a multidisciplinary approach must be taken to improve our understanding of this rhizosphere. Hence, "The Rhizosphere: Biochemistry and Organic S...

  18. PHYTOTOX: DATABASE DEALING WITH THE EFFECT OF ORGANIC CHEMICALS ON TERRESTRIAL VASCULAR PLANTS

    EPA Science Inventory

    A new database, PHYTOTOX, dealing with the direct effects of exogenously supplied organic chemicals on terrestrial vascular plants is described. The database consists of two files, a Reference File and Effects File. The Reference File is a bibliographic file of published research...

  19. SAMPLING FOR HIGH-MOLECULAR-WEIGHT ORGANIC COMPOUNDS IN POWER PLANT STACK GASES

    EPA Science Inventory

    The results of laboratory and field investigations of experimental sampling systems intended to collect high-molecular-weight organic compounds from flue gases in coal-fired power plants are presented. The most promising sampling device was a solid sorbent cartridge inserted dire...

  20. PARTITIONING OF TOXIC ORGANIC COMPOUNDS ON MUNICIPAL WASTEWATER TREATMENT PLANT SOLIDS

    EPA Science Inventory

    Fundamental aspects of partitioning of toxic organic compounds on municipal wastewater treatment plant solids have been investigated. Sorption on wastewater solids was not affected by solids-to-liquid ratio. Kinetic data on sorption showed an initial rapid uptake followed by a sl...

  1. EBP1 regulates organ size through cell growth and proliferation in plants

    PubMed Central

    Horváth, Beatrix M; Magyar, Zoltán; Zhang, Yuexing; Hamburger, Anne W; Bakó, László; Visser, Richard G F; Bachem, Christian W B; Bögre, László

    2006-01-01

    Plant organ size shows remarkable uniformity within species indicating strong endogenous control. We have identified a plant growth regulatory gene, functionally and structurally homologous to human EBP1. Plant EBP1 levels are tightly regulated; gene expression is highest in developing organs and correlates with genes involved in ribosome biogenesis and function. EBP1 protein is stabilised by auxin. Elevating or decreasing EBP1 levels in transgenic plants results in a dose-dependent increase or reduction in organ growth, respectively. During early stages of organ development, EBP1 promotes cell proliferation, influences cell-size threshold for division and shortens the period of meristematic activity. In postmitotic cells, it enhances cell expansion. EBP1 is required for expression of cell cycle genes; CyclinD3;1, ribonucleotide reductase 2 and the cyclin-dependent kinase B1;1. The regulation of these genes by EBP1 is dose and auxin dependent and might rely on the effect of EBP1 to reduce RBR1 protein level. We argue that EBP1 is a conserved, dose-dependent regulator of cell growth that is connected to meristematic competence and cell proliferation via regulation of RBR1 level. PMID:17024182

  2. Volatile organic compound emissions from usaf wastewater treatment plants in ozone nonattainment areas. Master's thesis

    SciTech Connect

    Ouellette, B.A.

    1994-09-01

    In accordance with the 1990 Clean Air Act Amendments (CAAA), this research conducts an evaluation of the potential emission of volatile organic compounds (VOCs) from selected Air Force wastewater treatment plants. Using a conservative mass balance analysis and process specific simulation models, volatile organic emission estimates are calculated for four individual facilities--Edwards AFB, Luke AFB, McGuire AFB, and McClellan AFB--which represent a cross section of the current inventory of USAF wastewater plants in ozone nonattainment areas. From these calculations, maximum facility emissions are determined which represent the upper limit for the potential VOC emissions from these wastewater plants. Based on the calculated emission estimates, each selected wastewater facility is evaluated as a potential major stationary source of volatile organic emissions under both Title I of the 1990 CAAA and the plant's governing Clean Air Act state implementation plan. Next, the potential impact of the specific volatile organics being emitted is discussed in terms of their relative reactivity and individual contribution to tropospheric ozone formation. Finally, a relative comparison is made between the estimated VOC emissions for the selected wastewater facilities and the total VOC emissions for their respective host installations.

  3. Weed management practices for organic production of trailing blackberry. I. Plant growth and early fruit production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed management practices were evaluated in a new field of trailing blackberry established in western Oregon. The field was planted in May 2010 and certified organic in May 2012. Treatments included two cultivars, ‘Marion’ and ‘Black Diamond’, grown in 1) non-weeded plots, where weeds were cut to th...

  4. Plant-derived compounds stimulate the decomposition of organic matter in arctic permafrost soils.

    PubMed

    Wild, Birgit; Gentsch, Norman; Čapek, Petr; Diáková, Kateřina; Alves, Ricardo J Eloy; Bárta, Jiři; Gittel, Antje; Hugelius, Gustaf; Knoltsch, Anna; Kuhry, Peter; Lashchinskiy, Nikolay; Mikutta, Robert; Palmtag, Juri; Schleper, Christa; Schnecker, Jörg; Shibistova, Olga; Takriti, Mounir; Torsvik, Vigdis L; Urich, Tim; Watzka, Margarete; Šantrůčková, Hana; Guggenberger, Georg; Richter, Andreas

    2016-01-01

    Arctic ecosystems are warming rapidly, which is expected to promote soil organic matter (SOM) decomposition. In addition to the direct warming effect, decomposition can also be indirectly stimulated via increased plant productivity and plant-soil C allocation, and this so called "priming effect" might significantly alter the ecosystem C balance. In this study, we provide first mechanistic insights into the susceptibility of SOM decomposition in arctic permafrost soils to priming. By comparing 119 soils from four locations across the Siberian Arctic that cover all horizons of active layer and upper permafrost, we found that an increased availability of plant-derived organic C particularly stimulated decomposition in subsoil horizons where most of the arctic soil carbon is located. Considering the 1,035 Pg of arctic soil carbon, such an additional stimulation of decomposition beyond the direct temperature effect can accelerate net ecosystem C losses, and amplify the positive feedback to global warming. PMID:27157964

  5. Plant-derived compounds stimulate the decomposition of organic matter in arctic permafrost soils

    PubMed Central

    Wild, Birgit; Gentsch, Norman; Čapek, Petr; Diáková, Kateřina; Alves, Ricardo J. Eloy; Bárta, Jiři; Gittel, Antje; Hugelius, Gustaf; Knoltsch, Anna; Kuhry, Peter; Lashchinskiy, Nikolay; Mikutta, Robert; Palmtag, Juri; Schleper, Christa; Schnecker, Jörg; Shibistova, Olga; Takriti, Mounir; Torsvik, Vigdis L.; Urich, Tim; Watzka, Margarete; Šantrůčková, Hana; Guggenberger, Georg; Richter, Andreas

    2016-01-01

    Arctic ecosystems are warming rapidly, which is expected to promote soil organic matter (SOM) decomposition. In addition to the direct warming effect, decomposition can also be indirectly stimulated via increased plant productivity and plant-soil C allocation, and this so called “priming effect” might significantly alter the ecosystem C balance. In this study, we provide first mechanistic insights into the susceptibility of SOM decomposition in arctic permafrost soils to priming. By comparing 119 soils from four locations across the Siberian Arctic that cover all horizons of active layer and upper permafrost, we found that an increased availability of plant-derived organic C particularly stimulated decomposition in subsoil horizons where most of the arctic soil carbon is located. Considering the 1,035 Pg of arctic soil carbon, such an additional stimulation of decomposition beyond the direct temperature effect can accelerate net ecosystem C losses, and amplify the positive feedback to global warming. PMID:27157964

  6. Plant-derived compounds stimulate the decomposition of organic matter in arctic permafrost soils

    NASA Astrophysics Data System (ADS)

    Wild, Birgit; Gentsch, Norman; Čapek, Petr; Diáková, Kateřina; Alves, Ricardo J. Eloy; Bárta, Jiři; Gittel, Antje; Hugelius, Gustaf; Knoltsch, Anna; Kuhry, Peter; Lashchinskiy, Nikolay; Mikutta, Robert; Palmtag, Juri; Schleper, Christa; Schnecker, Jörg; Shibistova, Olga; Takriti, Mounir; Torsvik, Vigdis L.; Urich, Tim; Watzka, Margarete; Šantrůčková, Hana; Guggenberger, Georg; Richter, Andreas

    2016-05-01

    Arctic ecosystems are warming rapidly, which is expected to promote soil organic matter (SOM) decomposition. In addition to the direct warming effect, decomposition can also be indirectly stimulated via increased plant productivity and plant-soil C allocation, and this so called “priming effect” might significantly alter the ecosystem C balance. In this study, we provide first mechanistic insights into the susceptibility of SOM decomposition in arctic permafrost soils to priming. By comparing 119 soils from four locations across the Siberian Arctic that cover all horizons of active layer and upper permafrost, we found that an increased availability of plant-derived organic C particularly stimulated decomposition in subsoil horizons where most of the arctic soil carbon is located. Considering the 1,035 Pg of arctic soil carbon, such an additional stimulation of decomposition beyond the direct temperature effect can accelerate net ecosystem C losses, and amplify the positive feedback to global warming.

  7. Genes and quantitative genetic variation involved with senescence in cells, organs, and the whole plant

    PubMed Central

    Pujol, Benoit

    2015-01-01

    Senescence, the deterioration of morphological, physiological, and reproductive functions with age that ends with the death of the organism, was widely studied in plants. Genes were identified that are linked to the deterioration of cells, organs and the whole plant. It is, however, unclear whether those genes are the source of age dependent deterioration or get activated to regulate such deterioration. Furthermore, it is also unclear whether such genes are active as a direct consequence of age or because they are specifically involved in some developmental stages. At the individual level, it is the relationship between quantitative genetic variation, and age that can be used to detect the genetic signature of senescence. Surprisingly, the latter approach was only scarcely applied to plants. This may be the consequence of the demanding requirements for such approaches and/or the fact that most research interest was directed toward plants that avoid senescence. Here, I review those aspects in turn and call for an integrative genetic theory of senescence in plants. Such conceptual development would have implications for the management of plant genetic resources and generate progress on fundamental questions raised by aging research. PMID:25755664

  8. The brighter side of soils: quantum dots track organic nitrogen through fungi and plants.

    PubMed

    Whiteside, Matthew D; Treseder, Kathleen K; Atsatt, Peter R

    2009-01-01

    Soil microorganisms mediate many nutrient transformations that are central in terrestrial cycling of carbon and nitrogen. However, uptake of organic nutrients by microorganisms is difficult to study in natural systems. We assessed quantum dots (fluorescent nanoscale semiconductors) as a new tool to observe uptake and translocation of organic nitrogen by fungi and plants. We conjugated quantum dots to the amino groups of glycine, arginine, and chitosan and incubated them with Penicillium fungi (a saprotroph) and annual bluegrass (Poa annua) inoculated with arbuscular mycorrhizal fungi. As experimental controls, we incubated fungi and bluegrass samples with substrate-free quantum dots as well as unbound quantum dot substrate mixtures. Penicillium fungi, annual bluegrass, and arbuscular mycorrhizal fungi all showed uptake and translocation of quantum dot-labeled organic nitrogen, but no uptake of quantum dot controls. Additionally, we observed quantum dot-labeled organic nitrogen within soil hyphae, plant roots, and plant shoots using field imaging techniques. This experiment is one of the first to demonstrate direct uptake of organic nitrogen by arbuscular mycorrhizal fungi. PMID:19294917

  9. Chemical characteristics of organic aerosols in Algiers city area: influence of a fat manufacture plant

    NASA Astrophysics Data System (ADS)

    Yassaa, Noureddine; Meklati, Brahim Youcef; Cecinato, Angelo

    Total concentrations and homologue distributions of organic fraction constituents have been determined in particulate matter emitted from different units of a fat manufacturer (i.e. oils refining and conditioning plants, and production and conditioning units of a soap industry) located in Algiers area, as well as in atmospheric aerosols. In particular n-alkanes, n-alkanoic and n-alkenoic acids, n-alkan-2-ones and polycyclic aromatic hydrocarbons (PAH) were investigated. Organic aerosol contents varied broadly among the plant units, depending upon nature of the manufactured products. The percent composition of all classes of compounds investigated in ambient atmosphere was similar to those observed indoor at industrial plant units. Organic acids, n-alkanoic as well as n-alkenoic, appeared by far the most abundant organic constituents of aerosols, both indoor and outdoor, ranging from 7.7 to 19.8 and from 12.7 to 17.1 μg m -3, respectively. The huge occurrence of acids and n-alkanes in ambient aerosols was consistent with their high levels present in oil and fat materials. Among minor components of aerosols, n-alkan-2-ones and PAH, seemed to be related to thermally induced ageing and direct combustion of raw organic material used for oil and soap production.

  10. A New Organic Dye-Based Staining for The Detection of Plant DNA in Agarose Gels.

    PubMed

    Sönmezoğlu, Özlem Ateş; Özkay, Kerime

    2015-01-01

    Ethidium bromide (EtBr) is used to stain DNA in agarose gel electrophoresis, but this dye is mutagenic and carcinogenic. We investigated N-719, which is a visible, reliable and organic Ruthenium-based dye, and five fluorescent alternatives for staining plant DNA. For prestaining and poststaining, N-719, GelRed, and SYBR Safe stained both DNA and PCR product bands as clearly as EtBr. SYBR Green I, methylene blue, and crystal violet were effective for poststaining only. The organic dye N-719 stained DNA bands as sensitively and as clearly as EtBr. Consequently, organic dyes can be used as alternatives to EtBr in plant biotechnology studies. PMID:26158569

  11. Health Maintenance Organizations and the Elderly: Promises, Problems, and Prospects. Hearing before the Select Committee on Aging. House of Representatives, Ninety-Eighth Congress, Second Session (Boca Raton, Florida).

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. House Select Committee on Aging.

    This document contains the transcripts of witness testimony and prepared statements from the Congressional hearing called to explore the impact of the Health Maintenance Organization (HMO) on the health care system and on the elderly in particular. Opening statements are given from Representatives Dan Mica, Matthew Rinaldo, and Lawrence Smith.…

  12. Representativity of mosses as biomonitor organisms for the accumulation of environmental chemicals in plants and soils

    SciTech Connect

    Thomas, W.

    1986-06-01

    The suitability of mosses for air pollution monitoring of benzohexachloride isomers and polyaromatic hydrocarbons is shown by residue data of different samples from Europe. The interpretation of the results makes it obvious that next to regional pattern analysis, hypotheses for atmospheric transport and deposition processes of different environmental chemicals can also be formed. An evaluation of these kinds of bioindicator methods is presented by a quantitative comparison of air pollution data and accumulated residues in plants. The results indicate a high retention efficiency of mosses for pollutants dominantly adsorbed to particulate matter in the air, like polyaromatic hydrocarbons and heavy metals. The comparison of residue data of trace pollutants in mosses and other plants underlines the indicator functions of lower plants for air monitoring patterns with the exception of chlorinated hydrocarbons. They are more effective enriched by coniferous plants which contain ingredients able to absorb and transport these groups of environmental pollutants in the organism.

  13. Organic Farming Benefits Local Plant Diversity in Vineyard Farms Located in Intensive Agricultural Landscapes

    NASA Astrophysics Data System (ADS)

    Nascimbene, Juri; Marini, Lorenzo; Paoletti, Maurizio G.

    2012-05-01

    The majority of research on organic farming has considered arable and grassland farming systems in Central and Northern Europe, whilst only a few studies have been carried out in Mediterranean agro-systems, such as vineyards, despite their economic importance. The main aim of the study was to test whether organic farming enhances local plant species richness in both crop and non-crop areas of vineyard farms located in intensive conventional landscapes. Nine conventional and nine organic farms were selected in an intensively cultivated region (i.e. no gradient in landscape composition) in northern Italy. In each farm, vascular plants were sampled in one vineyard and in two non-crop linear habitats, grass strips and hedgerows, adjacent to vineyards and therefore potentially influenced by farming. We used linear mixed models to test the effect of farming, and species longevity (annual vs. perennial) separately for the three habitat types. In our intensive agricultural landscapes organic farming promoted local plant species richness in vineyard fields, and grassland strips while we found no effect for linear hedgerows. Differences in species richness were not associated to differences in species composition, indicating that similar plant communities were hosted in vineyard farms independently of the management type. This negative effect of conventional farming was probably due to the use of herbicides, while mechanical operations and mowing regime did not differ between organic and conventional farms. In grassland strips, and only marginally in vineyards, we found that the positive effect of organic farming was more pronounced for perennial than annual species.

  14. Effects of light intensity light quality and air velocity on temperature in plant reproductive organs

    NASA Astrophysics Data System (ADS)

    Kitaya, Y.; Hirai, H.

    Excess temperature increase in plant reproductive organs such as anthers and stigmata could cause fertility impediments and thus produce sterile seeds under artificial lighting conditions in closed plant growth facilities There is a possibility that the aberration was caused by an excess increase in temperatures of reproductive organs in Bioregenerative Life Support Systems under microgravity conditions in space The fundamental study was conducted to know the thermal situation of the plant reproductive organs as affected by light intensity light quality and air velocity on the earth and to estimate the excess temperature increase in the reproductive organs in closed plant growth facilities in space Thermal images of reproductive organs of rice and strawberry were captured using infrared thermography at an air temperature of 10 r C The temperatures in flowers at 300 mu mol m -2 s -1 PPFD under the lights from red LEDs white LEDs blue LEDs fluorescent lamps and incandescent lamps increased by 1 4 1 7 1 9 6 0 and 25 3 r C respectively for rice and by 2 8 3 4 4 1 7 8 and 43 4 r C respectively for strawberry The flower temperatures increased with increasing PPFD levels The temperatures in petals anthers and stigmas of strawberry at 300 mu mol m -2 s -1 PPFD under incandescent lamps increased by 32 7 29 0 and 26 6 r C respectively at 0 1 m s -1 air velocity and by 20 6 18 5 and 15 9 r C respectively at 0 8 m s -1 air velocity The temperatures of reproductive organs decreased with increasing

  15. Phytoremediation of uranium-contaminated soils: Role of organic acids in triggering uranium hyperaccumulation in plants

    SciTech Connect

    Huang, J.W.; Blaylock, M.J.; Kapulnik, Y.; Ensley, B.D.

    1998-07-01

    Uranium phytoextraction, the use of plants to extract U from contaminated soils, is an emerging technology. The authors report on the development of this technology for the cleanup of U-contaminated soils. In this research, they investigated the effects of various soil amendments on U desorption from soil to soil solution, studied the physiological characteristics of U uptake and accumulation in plants, and developed techniques to trigger U hyperaccumulation in plants. A key to the success of U phytoextraction is to increase soil U availability to plants. The authors have found that some organic acids can be added to soils to increase U desorption from soil to soil solution and to trigger a rapid U accumulation in plants. Of the organic acids (acetic acid, citric acid, and malic acid) tested, citric acid was the most effective in enhancing U accumulation in plants. Shoot U concentrations of Brassica juncea and Brassica chinensis grown in a U-contaminated soil increased from less than 5 mg kg{sup {minus}1} to more than 5,000 mg kg{sup {minus}1} in citric acid-treated soils. To their knowledge, this is the highest shoot U concentration reported for plants grown on U-contaminated soils. Using this U hyperaccumulation technique, they are now able to increase U accumulation in shoots of selected plant species grown in two U-contaminated soils by more than 1,000-fold within a few days. The results suggest that U phytoextraction may provide an environmentally friendly alternative for the cleanup of U-contaminated soils.

  16. Periodontal maintenance.

    PubMed

    Tan, A E S

    2009-09-01

    The main goal of periodontal therapy is to establish an oral environment compatible with periodontal health by the physical disruption of the plaque biofilm and adjunctive chemical means if required. Implicit in this objective is the ongoing requirement of detection and interception of new and recurrent disease, which continues at selected intervals for the life of the dentition after the initial ("active") phase of periodontal treatment. This concept of ongoing periodontal maintenance therapy has been embraced as the mandatory requirement for favourable periodontal outcomes based on institutional clinical trials and in practice-based studies in various parts of the world. This review examines the ramifications of periodontal maintenance therapy based upon a multi-level assessment of logistic issues and risk factors at three levels: (1) The patient level - treatment time; patient attendance compliance; and homecare measures, antiseptics/antibiotics and smoking. (2) The level of the individual tooth - tooth loss; and evaluation of success versus survival. (3) The level of each tooth surface ("site") - probing depth, loss of attachment and bleeding on probing; and changes in clinical attachment levels. In spite of the diversity of studies conducted, there is agreement on the efficacy of periodontal maintenance therapy when compared with studies on untreated populations and in treated cases that were not maintained. PMID:19737263

  17. Overview of organic amendments for management of plant-parasitic nematodes, with case studies from Florida.

    PubMed

    McSorley, Robert

    2011-06-01

    Organic amendments have been widely used for management of plant-parasitic nematodes. Relatively rapid declines in nematode population levels may occur when decomposing materials release toxic compounds, while longer-term effects might include increases in nematode antagonists. Improved crop nutrition and plant growth following amendment use may lead to tolerance of plant-parasitic nematodes. Results depend on a great variety of factors such as material used, processing/composting of material, application rate, test arena, crop rotation and agronomic practices, soil type, climate, and other environmental factors. Reasons for variable performance and interpretation of results from amendment studies are discussed. Case studies of amendments for nematode management are reviewed from Florida, where composts and crop residues are the most frequently used amendments. Plant growth was often improved by amendment application, free-living nematodes (especially bacterivores) were often stimulated, but suppression of plant-parasitic nematodes was inconsistent. Amendments were generally not as effective as soil fumigation with methyl bromide for managing root-knot nematodes (Meloidogyne spp.), and often population levels or galling of root-knot nematodes in amended plots did not differ from those in non-amended control plots. While amendments may improve plant growth and stimulate soil food webs, additional study and testing are needed before they could be used reliably for management of plant-parasitic nematodes under Florida conditions. PMID:22791915

  18. Overview of Organic Amendments for Management of Plant-Parasitic Nematodes, with Case Studies from Florida

    PubMed Central

    2011-01-01

    Organic amendments have been widely used for management of plant-parasitic nematodes. Relatively rapid declines in nematode population levels may occur when decomposing materials release toxic compounds, while longer-term effects might include increases in nematode antagonists. Improved crop nutrition and plant growth following amendment use may lead to tolerance of plant-parasitic nematodes. Results depend on a great variety of factors such as material used, processing/composting of material, application rate, test arena, crop rotation and agronomic practices, soil type, climate, and other environmental factors. Reasons for variable performance and interpretation of results from amendment studies are discussed. Case studies of amendments for nematode management are reviewed from Florida, where composts and crop residues are the most frequently used amendments. Plant growth was often improved by amendment application, free-living nematodes (especially bacterivores) were often stimulated, but suppression of plant-parasitic nematodes was inconsistent. Amendments were generally not as effective as soil fumigation with methyl bromide for managing root-knot nematodes (Meloidogyne spp.), and often population levels or galling of root-knot nematodes in amended plots did not differ from those in non-amended control plots. While amendments may improve plant growth and stimulate soil food webs, additional study and testing are needed before they could be used reliably for management of plant-parasitic nematodes under Florida conditions. PMID:22791915

  19. Microextraction techniques for the determination of volatile and semivolatile organic compounds from plants: a review.

    PubMed

    Yang, Cui; Wang, Juan; Li, Donghao

    2013-10-17

    Vegetables and fruits are necessary for human health, and traditional Chinese medicine that uses plant materials can cure diseases. Thus, understanding the composition of plant matrix has gained increased attention in recent years. Since plant matrix is very complex, the extraction, separation and quantitation of these chemicals are challenging. In this review we focus on the microextraction techniques used in the determination of volatile and semivolatile organic compounds (such as esters, alcohols, aldehydes, hydrocarbons, ketones, terpenes, sesquiterpene, phenols, acids, plant secondary metabolites and pesticides) from plants (e.g., fruits, vegetables, medicinal plants, tree leaves, etc.). These microextraction techniques include: solid phase microextraction (SPME), stir-bar sorptive extraction (SBSE), single drop microextraction (SDME), hollow fiber liquid phase microextraction (HF-LPME), dispersive liquid liquid microextraction (DLLME), and gas purge microsyringe extraction (GP-MSE). We have taken into consideration papers published from 2008 to the end of January 2013, and provided critical and interpretative review on these techniques, and formulated future trends in microextraction for the determination of volatile and semivolatile compounds from plants. PMID:24091369

  20. Pollen Organ Telangiopsis sp. of Late Devonian Seed Plant and Associated Vegetative Frond.

    PubMed

    Wang, De-Ming; Meng, Mei-Cen; Guo, Yun

    2016-01-01

    Pollen organ Telangiopsis sp., associated with but not attached to vegetative fronds, has been collected from the Upper Devonian (Famennian) Wutong Formation, Dongzhi County, Anhui Province, China. Fertile axes with terminal pollen organs are dichotomous for 2-4 times and may be proximally attached by fragmentary pinnules. Pollen organs are synangiate and borne on the top of a short stalk. Synangia are radial in symmetry and each consists of 4-8 elongate microsporangia fused at base. Microsporangia have a longitudinal dehiscence line and show a tapered apex. The associated stem is spiny and bears a vegetative frond which bifurcates once at the basalmost part. Frond rachises possess one order of pinna arranged alternately. Pinnules are borne alternately, planate, highly dissected, and equally dichotomous for 2-3 times. Comparisons among Late Devonian seed plants recognize several branching patterns in the fertile fronds/axes bearing terminal pollen organs. Telangiopsis sp. reinforces that the Late Devonian pollen organs are synangiate usually with basally fused microsporangia. It is suggested that the evolutionary divergence of radial and bilateral symmetries of pollen organs may have occurred in the Famennian, when the earliest seed plants evolved planate and sometimes laminate pinnules. PMID:26808271

  1. Pollen Organ Telangiopsis sp. of Late Devonian Seed Plant and Associated Vegetative Frond

    PubMed Central

    Guo, Yun

    2016-01-01

    Pollen organ Telangiopsis sp., associated with but not attached to vegetative fronds, has been collected from the Upper Devonian (Famennian) Wutong Formation, Dongzhi County, Anhui Province, China. Fertile axes with terminal pollen organs are dichotomous for 2–4 times and may be proximally attached by fragmentary pinnules. Pollen organs are synangiate and borne on the top of a short stalk. Synangia are radial in symmetry and each consists of 4–8 elongate microsporangia fused at base. Microsporangia have a longitudinal dehiscence line and show a tapered apex. The associated stem is spiny and bears a vegetative frond which bifurcates once at the basalmost part. Frond rachises possess one order of pinna arranged alternately. Pinnules are borne alternately, planate, highly dissected, and equally dichotomous for 2–3 times. Comparisons among Late Devonian seed plants recognize several branching patterns in the fertile fronds/axes bearing terminal pollen organs. Telangiopsis sp. reinforces that the Late Devonian pollen organs are synangiate usually with basally fused microsporangia. It is suggested that the evolutionary divergence of radial and bilateral symmetries of pollen organs may have occurred in the Famennian, when the earliest seed plants evolved planate and sometimes laminate pinnules. PMID:26808271

  2. Soil organic matter decomposition follows plant productivity response to sea-level rise

    NASA Astrophysics Data System (ADS)

    Mueller, Peter; Jensen, Kai; Megonigal, James Patrick

    2015-04-01

    The accumulation of soil organic matter (SOM) is an important mechanism for many tidal wetlands to keep pace with sea-level rise. SOM accumulation is governed by the rates of production and decomposition of organic matter. While plant productivity responses to sea-level rise are well understood, far less is known about the response of SOM decomposition to accelerated sea-level rise. Here we quantified the effects of sea-level rise on SOM decomposition by exposing planted and unplanted tidal marsh monoliths to experimentally manipulated flood duration. The study was performed in a field-based mesocosm facility at the Smithsonian Global Change Research Wetland, a micro tidal brackish marsh in Maryland, US. SOM decomposition was quantified as CO2 efflux, with plant- and SOM-derived CO2 separated using a stable carbon isotope approach. Despite the dogma that decomposition rates are inversely related to flooding, SOM mineralization was not sensitive to varying flood duration over a 35 cm range in surface elevation in unplanted mesocoms. In the presence of plants, decomposition rates were strongly and positively related to aboveground biomass (p≤0.01, R2≥0.59). We conclude that rates of soil carbon loss through decomposition are driven by plant responses to sea level in this intensively studied tidal marsh. If our result applies more generally to tidal wetlands, it has important implications for modeling carbon sequestration and marsh accretion in response to accelerated sea-level rise.

  3. Maintenance Staffing Guidelines For Educational Facilities.

    ERIC Educational Resources Information Center

    APPA: Association of Higher Education Facilities Officers, Alexandria, VA.

    The purpose of this publication is to provide a resource or guide for educational facilities in establishing or developing a maintenance trades organization that is sufficient to accomplish basic facilities maintenance functions. The guidelines are intended to suggest staffing levels for those routine facilities maintenance activities that are…

  4. A Synthetic Polymer Scaffold Reveals the Self-Maintenance Strategies of Rat Glioma Stem Cells by Organization of the Advantageous Niche.

    PubMed

    Tabu, Kouichi; Muramatsu, Nozomi; Mangani, Christian; Wu, Mei; Zhang, Rong; Kimura, Taichi; Terashima, Kazuo; Bizen, Norihisa; Kimura, Ryosuke; Wang, Wenqian; Murota, Yoshitaka; Kokubu, Yasuhiro; Nobuhisa, Ikuo; Kagawa, Tetsushi; Kitabayashi, Issay; Bradley, Mark; Taga, Tetsuya

    2016-05-01

    Cancer stem cells (CSCs) are believed to be maintained within a microenvironmental niche. Here we used polymer microarrays for the rapid and efficient identification of glioma CSC (GSC) niche mimicries and identified a urethane-based synthetic polymer, upon which two groups of niche components, namely extracellular matrices (ECMs) and iron are revealed. In cultures, side population (SP) cells, defined as GSCs in the rat C6 glioma cell line, are more efficiently sustained in the presence of their differentiated progenies expressing higher levels of ECMs and transferrin, while in xenografts, ECMs are supplied by the vascular endothelial cells (VECs), including SP cell-derived ones with distinctively greater ability to retain xenobiotics than host VECs. Iron is stored in tumor infiltrating host macrophages (Mφs), whose protumoral activity is potently enhanced by SP cell-secreted soluble factor(s). Finally, coexpression of ECM-, iron-, and Mφ-related genes is found to be predictive of glioma patients' outcome. Our polymer-based approach reveals the intrinsic capacities of GSCs, to adapt the environment to organize a self-advantageous microenvironment niche, for their maintenance and expansion, which redefines the current concept of anti-CSC niche therapy and has the potential to accelerate cancer therapy development. Stem Cells 2016;34:1151-1162. PMID:26822103

  5. Use of and interest in alternative therapies among adult primary care clinicians and adult members in a large health maintenance organization.

    PubMed Central

    Gordon, N P; Sobel, D S; Tarazona, E Z

    1998-01-01

    During spring 1996, random samples of adult primary care physicians, obstetrics-gynecology physicians and nurse practitioners, and adult members of a large northern California group practice model health maintenance organization (HMO) were surveyed by mail to assess the use of alternative therapies and the extent of interest in having them incorporated into HMO-delivered care. Sixty-one percent (n = 624) of adult primary care physicians, 70% (n = 157) of obstetrics-gynecology clinicians, and 50% (2 surveys, n = 1,507 and n = 17,735) of adult HMO members responded. During the previous 12 months, 25% of adults reported using and nearly 90% of adult primary care physicians and obstetrics-gynecology clinicians reported recommending at least 1 alternative therapy, primarily for pain management. Chiropractic, acupuncture, massage, and behavioral medicine techniques such as meditation and relaxation training were most often cited. Obstetrics-gynecology clinicians used herbal and homeopathic medicines more often than adult primary care physicians, primarily for menopause and premenstrual syndrome. Two thirds of adult primary care physicians and three fourths of obstetrics-gynecology clinicians were at least moderately interested in using alternative therapies with patients, and nearly 70% of young and middle-aged adult and half of senior adult members were interested in having alternative therapies incorporated into their health care. Adult primary care physicians and members were more interested in having the HMO cover manipulative and behavioral medicine therapies than homeopathic or herbal medicines. PMID:9771154

  6. Use of and interest in alternative therapies among adult primary care clinicians and adult members in a large health maintenance organization.

    PubMed

    Gordon, N P; Sobel, D S; Tarazona, E Z

    1998-09-01

    During spring 1996, random samples of adult primary care physicians, obstetrics-gynecology physicians and nurse practitioners, and adult members of a large northern California group practice model health maintenance organization (HMO) were surveyed by mail to assess the use of alternative therapies and the extent of interest in having them incorporated into HMO-delivered care. Sixty-one percent (n = 624) of adult primary care physicians, 70% (n = 157) of obstetrics-gynecology clinicians, and 50% (2 surveys, n = 1,507 and n = 17,735) of adult HMO members responded. During the previous 12 months, 25% of adults reported using and nearly 90% of adult primary care physicians and obstetrics-gynecology clinicians reported recommending at least 1 alternative therapy, primarily for pain management. Chiropractic, acupuncture, massage, and behavioral medicine techniques such as meditation and relaxation training were most often cited. Obstetrics-gynecology clinicians used herbal and homeopathic medicines more often than adult primary care physicians, primarily for menopause and premenstrual syndrome. Two thirds of adult primary care physicians and three fourths of obstetrics-gynecology clinicians were at least moderately interested in using alternative therapies with patients, and nearly 70% of young and middle-aged adult and half of senior adult members were interested in having alternative therapies incorporated into their health care. Adult primary care physicians and members were more interested in having the HMO cover manipulative and behavioral medicine therapies than homeopathic or herbal medicines. PMID:9771154

  7. Eukaryotic Components Remodeled Chloroplast Nucleoid Organization during the Green Plant Evolution

    PubMed Central

    Kobayashi, Yusuke; Takusagawa, Mari; Harada, Naomi; Fukao, Yoichiro; Yamaoka, Shohei; Kohchi, Takayuki; Hori, Koichi; Ohta, Hiroyuki; Shikanai, Toshiharu; Nishimura, Yoshiki

    2016-01-01

    Chloroplast (cp) DNA is thought to originate from the ancestral endosymbiont genome and is compacted to form nucleoprotein complexes, cp nucleoids. The structure of cp nucleoids is ubiquitously observed in diverse plants from unicellular algae to flowering plants and is believed to be a multifunctional platform for various processes, including cpDNA replication, repair/recombination, transcription, and inheritance. Despite its fundamental functions, the protein composition for cp nucleoids in flowering plants was suggested to be divergent from those of bacteria and algae, but the evolutionary process remains elusive. In this research, we aimed to reveal the evolutionary history of cp nucleoid organization by analyzing the key organisms representing the three evolutionary stages of eukaryotic phototrophs: the chlorophyte alga Chlamydomonas reinhardtii, the charophyte alga Klebsormidium flaccidum, and the most basal land plant Marchantia polymorpha. To clarify the core cp nucleoid proteins in C. reinhardtii, we performed an LC-MS/MS analysis using highly purified cp nucleoid fractions and identified a novel SAP domain-containing protein with a eukaryotic origin as a constitutive core component. Then, homologous genes for cp nucleoid proteins were searched for in C. reinhardtii, K. flaccidum, and M. polymorpha using the genome databases, and their intracellular localizations and DNA binding activities were investigated by cell biological/biochemical analyses. Based on these results, we propose a model that recurrent modification of cp nucleoid organization by eukaryotic factors originally related to chromatin organization might have been the driving force for the diversification of cp nucleoids since the early stage of green plant evolution. PMID:26608058

  8. Leaf level emissions of volatile organic compounds (VOC) from some Amazonian and Mediterranean plants

    NASA Astrophysics Data System (ADS)

    Bracho-Nunez, A.; Knothe, N. M.; Welter, S.; Staudt, M.; Costa, W. R.; Liberato, M. A. R.; Piedade, M. T. F.; Kesselmeier, J.

    2012-11-01

    As volatile organic compounds (VOCs) significantly affect atmospheric chemistry (oxidative capacity) and physics (secondary organic aerosol formation and effects), emission inventories defining regional and global biogenic VOC emission strengths are important. The aim of this work was to achieve a description of VOC emissions from poorly described tropical vegetation to be compared with the quite well investigated and highly heterogeneous emissions from Mediterranean vegetation. For this task, common plant species of both ecosystems were investigated. Sixteen plant species from the Mediterranean area, which is known for its special diversity in VOC emitting plant species, were chosen. In contrast, little information is currently available regarding emissions of VOCs from tropical tree species at the leaf level. Twelve plant species from different environments of the Amazon basin, i.e. Terra firme, Várzea and Igapó, were screened for emission of VOCs at leaf level with a branch enclosure system. Analysis of the volatile organics was performed online by a proton-transfer-reaction mass spectrometer (PTR-MS) and offline by collection on adsorbent tubes and subsequent gas chromatographic analysis. Isoprene was quantitatively the most dominant compound emitted followed by monoterpenes, methanol and acetone. Most of the Mediterranean species emitted a variety of monoterpenes, whereas only five tropical species were monoterpene emitters exhibiting a quite conservative emission pattern (α-pinene > limonene > sabinene > β-pinene). Mediterranean plants showed additional emissions of sesquiterpenes, whereas in the case of plants from the Amazon region no sesquiterpenes were detected probably due to a lack of sensitivity in the measuring systems. On the other hand methanol emissions, an indicator of growth, were common in most of the tropical and Mediterranean species. A few species from both ecosystems showed acetone emissions. The observed heterogeneous emissions

  9. Plant growth response in experimental soilless mixes prepared from coal combustion products and organic waste materials

    SciTech Connect

    Bardhan, S.; Watson, M.; Dick, W.A.

    2008-07-15

    Large quantities of organic materials such as animal manures, yard trimmings, and biosolids are produced each year. Beneficial use options for them are often limited, and composting has been proposed as a way to better manage these organic materials. Similarly, burning of coal created 125 million tons of coal combustion products (CCP) in the United States in 2006. An estimated 53 million tons of CCP were reused, whereas the remainder was deposited in landfills. By combining CCP and composted organic materials (COM), we were able to create soilless plant growth mixes with physicochemical conditions that can support excellent plant growth. An additional benefit is the conservation of natural raw materials, such as peat, which is generally used for making soilless mixes. Experimental mixes were formulated by combining CCP and COM at ratios ranging from 2:8 to 8:2 (vol/vol), respectively. Water content at saturation for the created mixes was 63% to 72%, whereas for the commercial control, it was 77%. pH values for the best performing mixes ranged between 5.9 and 6.8. Electrical conductivity and concentrations of required plant nutrient were also within plant growth recommendations for container media. Significantly (P < 0.0001) higher plant biomass growth (7%-130%) was observed in the experimental mixes compared with a commercial mix. No additional fertilizers were provided during the experiment, and reduced fertilization costs can thus accrue as an added benefit to the grower. In summary, combining CCP and COM, derived from source materials often viewed as wastes, can create highly productive plant growth mixes.

  10. Refuse derived soluble bio-organics enhancing tomato plant growth and productivity

    SciTech Connect

    Sortino, Orazio; Dipasquale, Mauro; Montoneri, Enzo; Tomasso, Lorenzo; Perrone, Daniele G.; Vindrola, Daniela; Negre, Michele; Piccone, Giuseppe

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Municipal bio-wastes are a sustainable source of bio-based products. Black-Right-Pointing-Pointer Refuse derived soluble bio-organics promote chlorophyll synthesis. Black-Right-Pointing-Pointer Refuse derived soluble bio-organics enhance plant growth and fruit ripening rate. Black-Right-Pointing-Pointer Sustainable chemistry exploiting urban refuse allows sustainable development. Black-Right-Pointing-Pointer Chemistry, agriculture and the environment benefit from biowaste technology. - Abstract: Municipal bio-refuse (CVD), containing kitchen wastes, home gardening residues and public park trimmings, was treated with alkali to yield a soluble bio-organic fraction (SBO) and an insoluble residue. These materials were characterized using elemental analysis, potentiometric titration, and 13C NMR spectroscopy, and then applied as organic fertilizers to soil for tomato greenhouse cultivation. Their performance was compared with a commercial product obtained from animal residues. Plant growth, fruit yield and quality, and soil and leaf chemical composition were the selected performance indicators. The SBO exhibited the best performance by enhancing leaf chlorophyll content, improving plant growth and fruit ripening rate and yield. No product performance-chemical composition relationship could be assessed. Solubility could be one reason for the superior performance of SBO as a tomato growth promoter. The enhancement of leaf chlorophyll content is discussed to identify a possible link with the SBO photosensitizing properties that have been demonstrated in other work, and thus with photosynthetic performance.

  11. Organic halogens in unpolluted waters and large bodies of water receiving bleach plant effluents

    SciTech Connect

    Grimvall, A.; Jonsson, S.; Karlsson, S.; Savenhed, R.; Boren, H. )

    1991-05-01

    In this paper the authors review and update recently performed studies of organic halogens in unpolluted waters and two large bodies of water receiving bleach plant effluents---Lake Vattern in Sweden and the Baltic Sea. All water samples contained measurable amounts of adsorbable organic halogens (AOX); the highest concentrations (up to 200 {mu}g Cl/L) were observed in humic lakes not exposed to any industrial discharges. Analysis of chlorophenols revealed that there is a long-distance transport ({gt} 100 km) of chloroguaiacols from bleach plants to remote parts of receiving waters. However, there was no evidence of chlorinated organics from bleach plants accumulating over several years in the water phase. One chlorophenol, 2,4,6-trichlorophenol, and its methylated analogue, 2,4,6-trichloroanisole, were also detected in surface waters considered to be unpolluted. Mass balance calculations showed that different processes in terrestrial environments make large contributions of AOX; enzyme-mediated chlorination of humic substances is a plausible explanation to the widespread occurrence of organic halogens.

  12. Plants Regulate Soil Organic Matter Decomposition in Response to Sea Level Rise

    NASA Astrophysics Data System (ADS)

    Megonigal, P.; Mueller, P.; Jensen, K.

    2014-12-01

    Tidal wetlands have a large capacity for producing and storing organic matter, making their role in the global carbon budget disproportionate to their land area. Most of the organic matter stored in these systems is in soils where it contributes 2-5 times more to surface accretion than an equal mass of minerals. Soil organic matter (SOM) sequestration is the primary process by which tidal wetlands become perched high in the tidal frame, decreasing their vulnerability to accelerated sea level rise. Plant growth responses to sea level rise are well understood and represented in century-scale forecast models of soil surface elevation change. We understand far less about the response of soil organic matter decomposition to rapid sea level rise. Here we quantified the effects of sea level on SOM decomposition rates by exposing planted and unplanted tidal marsh monoliths to experimentally manipulated flood duration. The study was performed in a field-based mesocosm facility at the Smithsonian's Global Change Research Wetland. SOM decomposition rate was quantified as CO2 efflux, with plant- and SOM-derived CO2 separated with a two end-member δ13C-CO2 model. Despite the dogma that decomposition rates are inversely related to flooding, SOM mineralization was not sensitive to flood duration over a 35 cm range in soil surface elevation. However, decomposition rates were strongly and positively related to aboveground biomass (R2≥0.59, p≤0.01). We conclude that soil carbon loss through decomposition is driven by plant responses to sea level in this intensively studied tidal marsh. If this result applies more generally to tidal wetlands, it has important implications for modeling soil organic matter and surface elevation change in response to accelerated sea level rise.

  13. The 3D reconstruction of greenhouse tomato plant based on real organ samples and parametric L-system

    NASA Astrophysics Data System (ADS)

    Xin, Longjiao; Xu, Lihong; Li, Dawei; Fu, Daichang

    2014-04-01

    In this paper, a fast and effective 3D reconstruction method for the growth of greenhouse tomato plant is proposed by using real organ samples and a parametric L-system. By analyzing the stereo structure of tomato plant, we extracts rules and parameters to assemble an L-system that is able to simulate the plant growth, and then the components of the L-system are translated into plant organ entities via image processing and computer graphics techniques. This method can efficiently and faithfully simulate the growing process of the greenhouse tomato plant.

  14. Thermal treatment and leaching of biochar alleviates plant growth inhibition from mobile organic compounds

    PubMed Central

    Sackett, Tara E.; Thomas, Sean C.

    2016-01-01

    Recent meta-analyses of plant responses to biochar boast positive average effects of between 10 and 40%. Plant responses, however, vary greatly across systems, and null or negative biochar effects are increasingly reported. The mechanisms responsible for such responses remain unclear. In a glasshouse experiment we tested the effects of three forestry residue wood biochars, applied at five dosages (0, 5, 10, 20, and 50 t/ha) to a temperate forest drystic cambisol as direct surface applications and as complete soil mixes on the herbaceous pioneers Lolium multiflorum and Trifolium repens. Null and negative effects of biochar on growth were found in most cases. One potential cause for null and negative plant responses to biochar is plant exposure to mobile compounds produced during pyrolysis that leach or evolve following additions of biochars to soil. In a second glasshouse experiment we examined the effects of simple leaching and heating techniques to ameliorate potentially phytotoxic effects of volatile and leachable compounds released from biochar. We used Solid Phase Microextraction (SPME)–gas chromatography–mass spectrometry (GC-MS) to qualitatively describe organic compounds in both biochar (through headspace extraction), and in the water leachates (through direct injection). Convection heating and water leaching of biochar prior to application alleviated growth inhibition. Additionally, growth was inhibited when filtrate from water-leached biochar was applied following germination. SPME-GC-MS detected primarily short-chained carboxylic acids and phenolics in both the leachates and solid chars, with relatively high concentrations of several known phytotoxic compounds including acetic acid, butyric acid, 2,4-di-tert-butylphenol and benzoic acid. We speculate that variable plant responses to phytotoxic organic compounds leached from biochars may largely explain negative plant growth responses and also account for strongly species-specific patterns of plant

  15. In situ stimulation vs. bioaugmentation: Can microbial inoculation of plant roots enhance biodegradation of organic compounds?

    SciTech Connect

    Kingsley, M.T.; Metting, F.B. Jr.; Fredrickson, J.K.; Seidler, R.J.

    1993-06-01

    The use of plant roots and their associated rhizosphere bacteria for biocontainment and biorestoration offers several advantages for treating soil-dispersed contaminants and for application to large land areas. Plant roots function as effective delivery systems, since root growth transports bacteria vertically and laterally along the root in the soil column (see [ 1,2]). Movement of microbes along roots and downward in the soil column can be enhanced via irrigation [1-4]. For example, Ciafardini et al. [3] increased the nodulation and the final yield of soybeans during pod filling by including Bradyrhizobium japonicum in the irrigation water. Using rhizosphere microorganisms is advantageous for biodegradation of compounds that are degraded mainly by cometabolic processes, e.g., trichloroethylene (TCE). The energy source for bacterial growth and metabolism is supplied by the plant in the form of root exudates and other sloughed organic material. Plants are inexpensive, and by careful choice of species that possess either tap or fibrous root growth patterns, they can be used to influence mass transport of soil contaminants to the root surface via the transpiration stream [5]. Cropping of plants to remove heavy metals from contaminated soils has been proposed as a viable, low-cost, low-input treatment option [6]. The interest in use of plants as a remediation strategy has even reached the popular press [7], where the use of ragweed for the reclamation of sites contaminated with tetraethyl lead and other heavy metals was discussed.

  16. A portion of plant airborne communication is endorsed by uptake and metabolism of volatile organic compounds.

    PubMed

    Matsui, Kenji

    2016-08-01

    Plants have the ability to sense volatile organic compounds (VOCs) so as to efficiently adapt to their environment. The mechanisms underlying such plant 'olfactory' systems are largely unknown. Here I would like to propose that the metabolism of VOCs in plant tissues is one of the mechanisms by which plants sense VOCs. During the gas-exchange that is essential for photosynthesis, VOCs in the atmosphere are taken into the intercellular spaces of leaves. Each VOC is partitioned between the gas phase (intercellular space) and liquid phase (cell wall) at a certain ratio determined by Henry's law. The VOCs in the cell wall diffuse through the plasma membrane to the cytosol depending on their oil/water partition coefficients. Plants detoxify some VOCs, especially those that are oxidized, through glycosylation, glutathionylation, and reduction. These metabolic processes lower the concentration of VOCs in the cytosol, which facilitates further cytosolic uptake. As a result, vigorous metabolism of VOCs in the cytosol can lead to a substantial accumulation of VOC metabolites and the depletion of glutathione or NADPH. One such metabolite (a VOC glycoside) is known to mount a direct defense against herbivores, whilst deprivation of glutathione and NADPH can fortify plants with responses similar to the oxidative stress response. PMID:27281633

  17. Vascular Plant and Vertebrate Inventory of Organ Pipe Cactus National Monument

    USGS Publications Warehouse

    Schmidt, Cecilia A.; Powell, Brian F.; Halvorson, William L.

    2007-01-01

    Executive Summary We summarized inventory and monitoring efforts for plants and vertebrates at Organ Pipe Cactus National Monument (NM) in Arizona. We used data from previous research to compile complete species lists for the monument and to assess inventory completeness. There have been 1,031 species of plants and vertebrates observed at the monument. Most of the species on the list are documented by voucher specimens. There are 59 non-native species established in the monument: one mammal, three birds, and 55 non-native plants. Most non-native plant species were first recorded along roads. In each taxon-specific chapter, we highlight areas that contribute disproportionately to species richness or that have unique species for the monument. Of particular importance are Quitobaquito Springs and Pond, which are responsible for the monument having one of the highest number of bird species in the Sonoran Desert Network of parks. Quitobaquito also contains the only fish in the monument, the endangered Quitobaquito pupfish (Cyprinodon eremus). Other important resources for the plants and vertebrates include the xeroriparian washes (e.g., Alamo Canyon) and the Ajo Mountains. Based on the review of past studies, we believe the inventories of vascular plants and vertebrates are nearly complete and that the monument has one of the most complete inventories of any unit in the Sonoran Desert Network.

  18. Health Maintenance Organization (HMO) Plan

    MedlinePlus

    ... up/change plans About Medicare health plans Medicare Advantage Plans + Share widget - Select to show Subcategories Getting ... plan? About Medicare health plans , current subcategory Medicare Advantage Plans , current page Medicare Medical Savings Account (MSA) ...

  19. VIGS, HIGS and FIGS: small RNA silencing in the interactions of viruses or filamentous organisms with their plant hosts.

    PubMed

    Baulcombe, David C

    2015-08-01

    Recent evidence indicates two-way traffic of silencing RNA between filamentous organisms and their plant hosts. There are also indications that suppressors of RNA silencing are transferred from filamentous organisms into host plant cells where they influence the innate immune system. Here I use virus disease as a template for interpretation of RNA silencing in connection with filamentous organisms and infected plant cells. I propose that host plant interactions of these organisms are influenced by RNA silencing networks in which there are: small interfering RNAs from the host that are transported into the filamentous organism and vice versa; silencing suppressors from the organism that are transported into the host; endogenous small interfering RNAs and micro RNAs that target components of the innate immune system or endogenous suppressors of the innate immune system. PMID:26247121

  20. Spatial Structure of Seagrass Suggests That Size-Dependent Plant Traits Have a Strong Influence on the Distribution and Maintenance of Tropical Multispecies Meadows

    PubMed Central

    Ooi, Jillian L. S.; Van Niel, Kimberly P.; Kendrick, Gary A.; Holmes, Karen W.

    2014-01-01

    Background Seagrass species in the tropics occur in multispecies meadows. How these meadows are maintained through species co-existence and what their ecological drivers may be has been an overarching question in seagrass biogeography. In this study, we quantify the spatial structure of four co-existing species and infer potential ecological processes from these structures. Methods and Results Species presence/absence data were collected using underwater towed and dropped video cameras in Pulau Tinggi, Malaysia. The geostatistical method, utilizing semivariograms, was used to describe the spatial structure of Halophila spp, Halodule uninervis, Syringodium isoetifolium and Cymodocea serrulata. Species had spatial patterns that were oriented in the along-shore and across-shore directions, nested with larger species in meadow interiors, and consisted of multiple structures that indicate the influence of 2–3 underlying processes. The Linear Model of Coregionalization (LMC) was used to estimate the amount of variance contributing to the presence of a species at specific spatial scales. These distances were <2.5 m (micro-scale), 2.5–50 m (fine-scale) and >50 m (broad-scale) in the along-shore; and <2.5 m (micro-scale), 2.5–140 m (fine-scale) and >140 m (broad-scale) in the across-shore. The LMC suggests that smaller species (Halophila spp and H. uninervis) were most influenced by broad-scale processes such as hydrodynamics and water depth whereas large, localised species (S. isoetifolium and C. serrulata) were more influenced by finer-scale processes such as sediment burial, seagrass colonization and growth, and physical disturbance. Conclusion In this study, we provide evidence that spatial structure is distinct even when species occur in well-mixed multispecies meadows, and we suggest that size-dependent plant traits have a strong influence on the distribution and maintenance of tropical marine plant communities. This study offers a contrast from previous spatial

  1. Fossil organic carbon in wastewater and its fate in treatment plants.

    PubMed

    Law, Yingyu; Jacobsen, Geraldine E; Smith, Andrew M; Yuan, Zhiguo; Lant, Paul

    2013-09-15

    This study reports the presence of fossil organic carbon in wastewater and its fate in wastewater treatment plants. The findings pinpoint the inaccuracy of current greenhouse gas accounting guidelines which defines all organic carbon in wastewater to be of biogenic origin. Stable and radiocarbon isotopes ((13)C and (14)C) were measured throughout the process train in four municipal wastewater treatment plants equipped with secondary activated sludge treatment. Isotopic mass balance analyses indicate that 4-14% of influent total organic carbon (TOC) is of fossil origin with concentrations between 6 and 35 mg/L; 88-98% of this is removed from the wastewater. The TOC mass balance analysis suggests that 39-65% of the fossil organic carbon from the influent is incorporated into the activated sludge through adsorption or from cell assimilation while 29-50% is likely transformed to carbon dioxide (CO2) during secondary treatment. The fossil organic carbon fraction in the sludge undergoes further biodegradation during anaerobic digestion with a 12% decrease in mass. 1.4-6.3% of the influent TOC consists of both biogenic and fossil carbon is estimated to be emitted as fossil CO2 from activated sludge treatment alone. The results suggest that current greenhouse gas accounting guidelines, which assume that all CO2 emission from wastewater is biogenic may lead to underestimation of emissions. PMID:23863394

  2. Leaf level emissions of volatile organic compounds (VOC) from some Amazonian and Mediterranean plants

    NASA Astrophysics Data System (ADS)

    Bracho-Nunez, A.; Knothe, , N. M.; Welter, S.; Staudt, M.; Costa, W. R.; Liberato, M. A. R.; Piedade, M. T. F.; Kesselmeier, J.

    2013-09-01

    Emission inventories defining regional and global biogenic volatile organic compounds (VOC) emission strengths are needed to determine the impact of VOC on atmospheric chemistry (oxidative capacity) and physics (secondary organic aerosol formation and effects). The aim of this work was to contribute with measurements of tree species from the poorly described tropical vegetation in direct comparison with the quite well-investigated, highly heterogeneous emissions from Mediterranean vegetation. VOC emission from sixteen plant species from the Mediterranean area were compared with twelve plant species from different environments of the Amazon basin by an emission screening at leaf level using branch enclosures. Analysis of the volatile organics was performed online by a proton-transfer-reaction mass spectrometer (PTR-MS) and offline by collection on adsorbent tubes and subsequent gas chromatographic analysis. Isoprene was the most dominant compound emitted followed by monoterpenes, methanol and acetone. The average loss rates of VOC carbon in relation to the net CO2 assimilation were found below 4% and indicating normal unstressed plant behavior. Most of the Mediterranean species emitted a large variety of monoterpenes, whereas only five tropical species were identified as monoterpene emitters exhibiting a quite conservative emission pattern (α-pinene < limonene < sabinene < ß-pinene). Mediterranean plants showed additional emissions of sesquiterpenes. In the case of Amazonian plants no sesquiterpenes were detected. However, missing of sesquiterpenes may also be due to a lack of sensitivity of the measuring systems. Furthermore, our screening activities cover only 1% of tree species of such tropical areas as estimated based on recent biodiversity reports. Methanol emissions, an indicator of growth, were found to be common in most of the tropical and Mediterranean species. A few species from both ecosystems showed acetone emissions. The observed heterogeneous

  3. New methods for new data on plant organic carbon from sediments.

    NASA Astrophysics Data System (ADS)

    Descolas, C.; Bouvier, T.; Got, P.; Guittard, F.

    2009-04-01

    New methods for new data on plant organic carbon from sediments. Chantal Descolas-Gros1,Thierry Bouvier2, Patrice Got2, Frederic Guittard3 1 Institut des Sciences de l'Evolution Université Montpellier 2, CNRS, UMR 5554 Place Eugène Bataillon, Case Courrier 061, 34095 Montpellier cedex 05, France Email: Chantal.Descolas@univ-montp2.fr 2 Laboratoire Ecosystèmes Lagunaires, Université Montpellier 2, CNRS IFREMER UMR 5119 Place E. Bataillon, Case Courrier 093, 34095 Montpellier cedex 05, France. 3 Département de Chimie, Université Sophia Antipolis, 06000 Nice, France Vegetation distribution is linked to climatic and non-climatic factors. In the past, the knowledge of plant species distribution at different scales (global to regional) is a necessary step for climate simulating models. Pollen is one of the most important fossil plant remains and has been widely use for that purpose. But species level determinations are not possible in most cases on pollen. A physiological plant type basis (C3, C4 plants) is frequently employed to improve data accuracy. C3 and C4 plants may be characterized by the delta 13C values of pollen organic carbon. Biogeochemical methods using sporopollenin (a well preserved wall constituent of fossil pollen grains) as macromolecular proxy have been developed. We present here a combination of non-destructive methods, never used on fossil pollen grains. Specific pollen taxa has been isolated from sediments by cytometry and the structure of the sporopollenin is controlled by Attenuated Total Reflection Fourier Transform Infrared spectroscopy. This method allow further delta 13C measurements on the same material. Selected pollen taxa could be isolated in different levels from a sediment core and the structure of the sporopollenin is controlled before delta 13C measurements.

  4. The aquatic vascular plant Ruppia maritima as an indicator organisms for contaminated sediments

    SciTech Connect

    Tagliabue, M.D.; Thursby, G.B.; Walker, H.A.; Johnston, R.K.

    1994-12-31

    An ongoing estuarine ecological risk assessment case study for the Portsmouth Naval Shipyard in the Great Bay (Kittery, ME, Portsmouth, NH) has been the catalyst for continued methods development with a rooted aquatic plant for a sediment toxicity test. A test using the aquatic vascular plant Ruppia maritima would be similar in it`s utility to the Algal (Champia parvula) Reproduction Test, an accepted, short term test (US EPA Short term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms). Laboratory studies were conducted to evaluate effects of lead, the primary site contaminant on R. maritima in the Great Bay. Morphology and life cycle of R. maritima are similar to that of the aquatic vascular plant Zostra marina which comprises up to 46% of the Great Bay habitat (Short 1992). R. maritima`s reduced size makes it a practical laboratory organism and Ruppia`s effects may offer useful insights into potential effects on Zostra or other aquatic vascular plants. Presently rooted vascular plants are not found in the site of concern (Clark Cove). This can be contributed to either of two factors; the physical parameters of the site, i.e., a depositional zone or the chemical parameters, i.e., metals contamination, specifically lead. Exposure of bedded and nonbedded plants occurred over a four day and ten day period using lead sulfate. Concentrations for bedded exposures were as follows, 0.3, 0.5, 0.8, 1.0 simultaneously extracted metal/acid volatile sulfide (SEM/AVS) molar ratios, and 0.1, 1.0, 10.0 and 100.0mg/l Pb for water only exposures. Some reduction in cumulative leaf growth was observed in the site samples as well as the spiked samples as compared to site controls. Results of this study and associated research which focuses on the further development of the Ruppia test methods will be presented.

  5. Inverse modeling of the biodegradation of emerging organic contaminants in the soil-plant system.

    PubMed

    Hurtado, Carlos; Trapp, Stefan; Bayona, Josep M

    2016-08-01

    Understanding the processes involved in the uptake and accumulation of organic contaminants into plants is very important to assess the possible human risk associated with. Biodegradation of emerging contaminants in plants has been observed, but kinetical studies are rare. In this study, we analyse experimental data on the uptake of emerging organic contaminants into lettuce derived in a greenhouse experiment. Measured soil, root and leaf concentrations from four contaminants were selected within the applicability domain of a steady-state two-compartment standard plant uptake model: bisphenol A (BPA), carbamazepine (CBZ), triclosan (TCS) and caffeine (CAF). The model overestimated concentrations in most cases, when no degradation rates in plants were entered. Subsequently, biodegradation rates were fitted so that the measured concentrations were met. Obtained degradation kinetics are in the order, BPA < CAF ≈ TCS < CBZ in roots, and BPA ≈ TCS < CBZ < CAF in leaves. Kinetics determined by inverse modeling are, despite the inherent uncertainty, indicative of the dissipation rates. The advantage of the procedure that is additional knowledge can be gained from existing experimental data. Dissipation kinetics found via inverse modeling is not a conclusive proof for biodegradation and confirmation by experimental studies is needed. PMID:27179241

  6. Microcystin-LR and Cylindrospermopsin Induced Alterations in Chromatin Organization of Plant Cells

    PubMed Central

    Máthé, Csaba; M-Hamvas, Márta; Vasas, Gábor

    2013-01-01

    Cyanobacteria produce metabolites with diverse bioactivities, structures and pharmacological properties. The effects of microcystins (MCYs), a family of peptide type protein-phosphatase inhibitors and cylindrospermopsin (CYN), an alkaloid type of protein synthesis blocker will be discussed in this review. We are focusing mainly on cyanotoxin-induced changes of chromatin organization and their possible cellular mechanisms. The particularities of plant cells explain the importance of such studies. Preprophase bands (PPBs) are premitotic cytoskeletal structures important in the determination of plant cell division plane. Phragmoplasts are cytoskeletal structures involved in plant cytokinesis. Both cyanotoxins induce the formation of multipolar spindles and disrupted phragmoplasts, leading to abnormal sister chromatid segregation during mitosis. Thus, MCY and CYN are probably inducing alterations of chromosome number. MCY induces programmed cell death: chromatin condensation, nucleus fragmentation, necrosis, alterations of nuclease and protease enzyme activities and patterns. The above effects may be related to elevated reactive oxygen species (ROS) and/or disfunctioning of microtubule associated proteins. Specific effects: MCY-LR induces histone H3 hyperphosphorylation leading to incomplete chromatid segregation and the formation of micronuclei. CYN induces the formation of split or double PPB directly related to protein synthesis inhibition. Cyanotoxins are powerful tools in the study of plant cell organization. PMID:24084787

  7. [Impact of dissolved organic matter on plant uptake of phenanthrene and its mechanisms].

    PubMed

    Zhan, Xin-hua; Zhou, Li-xiang; Wan, Yin-jing; Jiang, Ting-hui

    2006-09-01

    Hydroponic assays were conducted to investigate the influence of dissolved organic matter on uptake of phenanthrene by wheat as well as its mechanisms. The results showed that, under hydroponic condition, phenanthrene impairment of plant growth occurred with wheat growth inhibited rate of 18.01%. The impairment would be greatly enhanced in the presence of dissolved organic matter (DOM) derived from pig manure, and the inhibited rate increased to 24.38%. Wheat could uptake and accumulate phenanthrene in the nutrient solution, which could be escalated by DOM, as indicated by wheat root bioconcentration factor being increased to 37.63 L x kg(-1) in the presence of DOM from 2.84 L x kg(-1) in the absence of DOM. At the same time, DOM could facilitate phenanthrene translocation from plant roots to the upper. As a result, the pH value of nutrient solution could increase by more than 1 unit when the co-existence of DOM and phenanthrene occurred in solution, suggesting that H+ -phenanthrene cotransport system is involved in the uptake of phenanthrene by plants. A synergism was also found between wheat uptakes of phenanthrene and inorganic nutrients, Moreover, DOM accelerated markedly the synergism. It is concluded that DOM affects the uptake of phenanthrene by plants and the environmental behaviors of phenanthrene. PMID:17117650

  8. Influence of organic matter on the uptake of cadmium, zinc, copper and iron by sorghum plants.

    PubMed

    Pinto, A P; Mota, A M; de Varennes, A; Pinto, F C

    2004-06-29

    This article describes an experiment, carried out under controlled environment conditions, to investigate the effects of a fulvic acid fraction of soil organic matter on growth, cadmium (Cd) uptake and redistribution by sorghum. In addition the uptake of copper (Cu), zinc (Zn) and iron (Fe) was also determined. Sorghum was grown in nutrient solutions with 0, 0.1, 1 and 10 mg Cd dm(-3), in the absence and presence of organic matter (32 mg C dm(-3)), for various periods up to 20 days. A decrease in sorghum biomass due to Cd toxicity was observed at 10 mg Cd dm(-3), but for concentrations of 0.1 and 1 mg Cd dm(-3) the biomass was increased compared with control, without visual toxicity symptoms. The presence of organic matter (OM) further increased biomass production. Cadmium was mainly retained in sorghum roots, as usually found in tolerant plants, but Cd accumulation in sorghum was greater than in other Gramineae, or even more tolerant plants such as lettuce. The presence of OM decreased the bioavailability of Cd that was partially retained in solution by the OM ligands. However, OM promoted the translocation of Cd to shoots, an effect that may pose a risk to public health because plant-animal transfer of Cd could be enhanced. The presence of OM decreased the uptake of Cu, Zn and Fe. The presence (vs. absence) of 0.1 mg Cd dm(-3) enhanced the uptake of Fe, both in the absence and presence of OM. PMID:15142779

  9. The simulation of organic rankine cycle power plant with n-pentane working fluid

    NASA Astrophysics Data System (ADS)

    Nurhilal, Otong; Mulyana, Cukup; Suhendi, Nendi; Sapdiana, Didi

    2016-02-01

    In the steam power plant in Indonesia the dry steam from separator directly used to drive the turbin. Meanwhile, brine from the separator with low grade temperature reinjected to the earth. The brine with low grade temperature can be converted indirectly to electrical power by organic Rankine cycle (ORC) methods. In ORC power plant the steam are released from vaporization of organic working fluid by brine. The steam released are used to drive an turbine which in connected to generator to convert the mechanical energy into electric energy. The objective of this research is the simulation ORC power plant with n-pentane as organic working fluid. The result of the simulation for brine temperature around 165°C and the pressure 8.001 bar optained the net electric power around 1173 kW with the cycle thermal efficiency 14.61% and the flow rate of n-pentane around 15.51 kg/s. This result enable to applied in any geothermal source in Indonesia.

  10. Organic amendments for improving biomass production and metal yield of Ni-hyperaccumulating plants.

    PubMed

    Álvarez-López, V; Prieto-Fernández, Á; Cabello-Conejo, M I; Kidd, P S

    2016-04-01

    Ni phytomining is a promising technology for Ni recovery from low-grade ores such as ultramafic soils. Metal-hyperaccumulators are good candidates for phytomining due to their extraordinary capacity for Ni accumulation. However, many of these plants produce a low biomass, which makes the use of agronomic techniques for improving their growth necessary. In this study, the Ni hyperaccumulators Alyssum serpyllifolium ssp. lusitanicum, A. serpyllifolium ssp. malacitanum, Alyssum bertolonii and Noccaea goesingense were evaluated for their Ni phytoextraction efficiency from a Ni-rich serpentine soil. Effects of soil inorganic fertilisation (100:100:125kgNPKha(-1)) and soil organic amendment addition (2.5, 5 or 10% compost) on plant growth and Ni accumulation were determined. All soil treatments greatly improved plant growth, but the highest biomass production was generally found after addition of 2.5 or 5% compost (w/w). The most pronounced beneficial effects were observed for N. goesingense. Total Ni phytoextracted from soils was significantly improved using both soil treatments (inorganic and organic), despite the decrease observed in soil Ni availability and shoot Ni concentrations in compost-amended soils. The most promising results were found using intermediate amount of compost, indicating that these types of organic wastes can be incorporated into phytomining systems. PMID:26803735

  11. Tightly-Coupled Plant-Soil Nitrogen Cycling: Comparison of Organic Farms across an Agricultural Landscape.

    PubMed

    Bowles, Timothy M; Hollander, Allan D; Steenwerth, Kerri; Jackson, Louise E

    2015-01-01

    How farming systems supply sufficient nitrogen (N) for high yields but with reduced N losses is a central challenge for reducing the tradeoffs often associated with N cycling in agriculture. Variability in soil organic matter and management of organic farms across an agricultural landscape may yield insights for improving N cycling and for evaluating novel indicators of N availability. We assessed yields, plant-soil N cycling, and root expression of N metabolism genes across a representative set of organic fields growing Roma-type tomatoes (Solanum lycopersicum L.) in an intensively-managed agricultural landscape in California, USA. The fields spanned a three-fold range of soil carbon (C) and N but had similar soil types, texture, and pH. Organic tomato yields ranged from 22.9 to 120.1 Mg ha-1 with a mean similar to the county average (86.1 Mg ha-1), which included mostly conventionally-grown tomatoes. Substantial variability in soil inorganic N concentrations, tomato N, and root gene expression indicated a range of possible tradeoffs between yields and potential for N losses across the fields. Fields showing evidence of tightly-coupled plant-soil N cycling, a desirable scenario in which high crop yields are supported by adequate N availability but low potential for N loss, had the highest total and labile soil C and N and received organic matter inputs with a range of N availability. In these fields, elevated expression of a key gene involved in root N assimilation, cytosolic glutamine synthetase GS1, confirmed that plant N assimilation was high even when inorganic N pools were low. Thus tightly-coupled N cycling occurred on several working organic farms. Novel combinations of N cycling indicators (i.e. inorganic N along with soil microbial activity and root gene expression for N assimilation) would support adaptive management for improved N cycling on organic as well as conventional farms, especially when plant-soil N cycling is rapid. PMID:26121264

  12. Tightly-Coupled Plant-Soil Nitrogen Cycling: Comparison of Organic Farms across an Agricultural Landscape

    PubMed Central

    Bowles, Timothy M.; Hollander, Allan D.; Steenwerth, Kerri; Jackson, Louise E.

    2015-01-01

    How farming systems supply sufficient nitrogen (N) for high yields but with reduced N losses is a central challenge for reducing the tradeoffs often associated with N cycling in agriculture. Variability in soil organic matter and management of organic farms across an agricultural landscape may yield insights for improving N cycling and for evaluating novel indicators of N availability. We assessed yields, plant-soil N cycling, and root expression of N metabolism genes across a representative set of organic fields growing Roma-type tomatoes (Solanum lycopersicum L.) in an intensively-managed agricultural landscape in California, USA. The fields spanned a three-fold range of soil carbon (C) and N but had similar soil types, texture, and pH. Organic tomato yields ranged from 22.9 to 120.1 Mg ha-1 with a mean similar to the county average (86.1 Mg ha-1), which included mostly conventionally-grown tomatoes. Substantial variability in soil inorganic N concentrations, tomato N, and root gene expression indicated a range of possible tradeoffs between yields and potential for N losses across the fields. Fields showing evidence of tightly-coupled plant-soil N cycling, a desirable scenario in which high crop yields are supported by adequate N availability but low potential for N loss, had the highest total and labile soil C and N and received organic matter inputs with a range of N availability. In these fields, elevated expression of a key gene involved in root N assimilation, cytosolic glutamine synthetase GS1, confirmed that plant N assimilation was high even when inorganic N pools were low. Thus tightly-coupled N cycling occurred on several working organic farms. Novel combinations of N cycling indicators (i.e. inorganic N along with soil microbial activity and root gene expression for N assimilation) would support adaptive management for improved N cycling on organic as well as conventional farms, especially when plant-soil N cycling is rapid. PMID:26121264

  13. Gravity response mechanisms of lateral organs and the control of plant architecture in Arabidopsis

    NASA Astrophysics Data System (ADS)

    Mullen, J.; Hangarter, R.

    Most research on gravity responses in plants has focused on primary roots and shoots, which typically grow in a vertical orientation. However, the patterns of lateral organ formation and their growth orientation, which typically are not vertical, govern plant architecture. For example, in Arabidopsis, when lateral roots emerge from the primary root, they grow at a nearly horizontal orientation. As they elongate, the roots slowly curve until they eventually reach a vertical orientation. The regulation of this lateral root orientation is an important component affecting the overall root system architecture. We have found that this change in orientation is not simply due to the onset of gravitropic competence, as non-vertical lateral roots are capable of both positive and negative gravitropism. Thus, the horizontal growth of the new lateral roots is determined by what is called the gravitropic set-point angle (GSA). In Arabidopsis shoots, rosette leaves and inflorescence branches also display GSA-dependent developmental changes in their orientation. The developmental control of the GSA of lateral organs in Arabidopsis provides us with a useful system for investigating the components involved in regulating directionality of tropistic responses. We have identified several Arabidopsis mutants that have either altered lateral root orientations, altered orientation of lateral organs in the shoot, or both, but maintain normal primary organ orientation. The mgsa ({m}odified {g}ravitropic {s}et-point {a}ngle) mutants with both altered lateral root and shoot orientation show that there are common components in the regulation of growth orientation in the different organs. Rosette leaves and lateral roots also have in common a regulation of positioning by red light. Further molecular and physiological analyses of the GSA mutants will provide insight into the basis of GSA regulation and, thus, a better understanding of how gravity controls plant architecture. [This work was

  14. Remote Maintenance Support in Virtual Service Enterprises

    NASA Astrophysics Data System (ADS)

    Kamio, Yoichi; Kasai, Fumio; Kimura, Toshiaki; Fukuda, Yoshiro; Hartel, Ingo; Zhou, Mingwei

    This paper discusses a scheme that allows all parties involved in the maintenance of a chemical plant: the plant owner (customer), the engineering company, the equipment vendors, and the maintenance firms, to form a virtual service enterprise (VSE) whenever a maintenance service is necessary, in an attempt to provide required services more timely. This paper also discusses the requirements for knowledge management and risk management in such a VSE environment, and proposes a secure hosting service environment that allows all the parties to share information and applications, and to collaborate during plant operation and service fulfilment. To evaluate and demonstrate the feasibility of this scheme, a prototype of the remote maintenance system developed for a fertiliser plant in Indonesia is presented. Finally, a scenario of how to utilise such a remote maintenance system, the possibility of collaboration among VSE partners, and the advantages of utilising the proposed hosting services in VSE are also discussed.

  15. The aquatic vascular plant Ruppia maritima as an indicator organism for contaminated sediments

    SciTech Connect

    Tagliabue, M.D.; Thursby, G.B.; Walker, H.A.; Johnston, R.K.

    1995-12-31

    An ongoing estuarine ecological risk assessment case study for the Portsmouth Naval Shipyard in the Great Bay Estuary (New Hampshire, Maine) was the catalyst to continue development a rooted aquatic plant sediment toxicity test. Laboratory studies were conducted to evaluate effects of lead, the primary site contaminant on R. maritima in the Great Bay. Although the aquatic vascular plant Zostra marina comprises up to 46% of the Great Bay subtidal habitat, R. maritima`s much smaller size makes it a more practical laboratory organism. Effects on Ruppia may offer useful insights into potential effects on Zostra or other aquatic vascular plants. Presently rooted vascular plants are not found in Clark Cove located adjacent to a landfill disposal site on the shipyard. The absence of rooted vegetation can be contributed to, physical parameters of the site (turbidity, grain size, texture) or chemical parameters (heavy metal/Pb contamination, redox potential). Exposure of bedded and nonbedded plants occurred over a four day and ten day period using lead sulfate. Concentrations for bedded exposures were as follows, 0.3, 0.5, 0.8, 1.0 simultaneously extracted metal/acid volatile sulfide (SEM/AVS) molar ratios, and 0.1, 1.0, 10.0 and 100.0mg/l Pb for water only exposures. Reduction in cumulative leaf growth was observed for the Clark Cove sediments as well as the spiked sediments as compared to reference sediments.

  16. Organic farmers use of wild food plants and fungi in a hilly area in Styria (Austria)

    PubMed Central

    2010-01-01

    Background Changing lifestyles have recently caused a severe reduction of the gathering of wild food plants. Knowledge about wild food plants and the local environment becomes lost when plants are no longer gathered. In Central Europe popular scientific publications have tried to counter this trend. However, detailed and systematic scientific investigations in distinct regions are needed to understand and preserve wild food uses. This study aims to contribute to these investigations. Methods Research was conducted in the hill country east of Graz, Styria, in Austria. Fifteen farmers, most using organic methods, were interviewed in two distinct field research periods between July and November 2008. Data gathering was realized through freelisting and subsequent semi-structured interviews. The culinary use value (CUV) was developed to quantify the culinary importance of plant species. Hierarchical cluster analysis was performed on gathering and use variables to identify culture-specific logical entities of plants. The study presented was conducted within the framework of the master's thesis about wild plant gathering of the first author. Solely data on gathered wild food species is presented here. Results Thirty-nine wild food plant and mushroom species were identified as being gathered, whereas 11 species were mentioned by at least 40 percent of the respondents. Fruits and mushrooms are listed frequently, while wild leafy vegetables are gathered rarely. Wild foods are mainly eaten boiled, fried or raw. Three main clusters of wild gathered food species were identified: leaves (used in salads and soups), mushrooms (used in diverse ways) and fruits (eaten raw, with milk (products) or as a jam). Conclusions Knowledge about gathering and use of some wild food species is common among farmers in the hill country east of Graz. However, most uses are known by few farmers only. The CUV facilitates the evaluation of the culinary importance of species and makes comparisons

  17. Assessing self-organization of plant communities--A thermodynamic approach

    NASA Astrophysics Data System (ADS)

    Lin, H.; Cao, M.; Stoy, P.; Zhang, Y.

    2013-12-01

    Thermodynamics is a powerful tool for the study of system development and has the potential to be applied to studies of ecological complexity. Here, we develop a set of thermodynamic indicators including energy capture and energy dissipation to quantify plant community self-organization. The study ecosystems included a tropical seasonal rainforest, an artificial tropical rainforest, a rubber plantation, and two Chromolaena odorata (L.) R.M. King & H. Robinson communities aged 13 years and 1 year. The communities represent a complexity transect from primary vegetation, to transitional community, economic plantation, and fallows and are typical for Xishuangbanna, southwestern China. The indicators of ecosystem self-organization are sensitive to plant community type and seasonality, and demonstrate that the tropical seasonal rainforest is highly self-organized and plays an important role in local environmental stability via the land surface thermal regulation. The rubber plantation is at a very low level of self-organization as quantified by the thermodynamic indicators, especially during the dry season. The expansion of the area of rubber plantation and shrinkage of tropical seasonal rainforest would likely induce local surface warming and a larger daily temperature range.

  18. Exposure to isophorone and other organic solvents in a screen printing plant.

    PubMed

    Samimi, B

    1982-01-01

    A study was conducted in a screen printing plant to determine the exposure of workers to isophorone and other organic solvents. One hundred twenty-four charcoal tube samples were collected from both workers breathing zones and various workplace areas. Sampling times were 50-90 minutes. Maximum mean TWACs of isophorone and cyclohexanone were 23 +/- 5.4 ppm and 28 +/- 5 ppm, respectively, at the breathing zones of printing press workers. Exposure levels for other organic vapors such as cellosolve acetate, butyl acetate, xylenes, diacetone alchohol, and petroleum distillate are also presented. Mean TWACs of personal samples were generally higher than area samples due to proximity of the solvent evaporating surfaces to the workers breathing zones. Mean TWACs for the individual organic vapors did not exceed OSHA Limits. However, the sum of (TWAC/TLV) ratios of organic vapors with additive health effects exceeded unity at the breathing zones of workers handling inks and solvents. Actual 8-hour worker exposures were assumed to be lower because workers were exposed to lower concentrations (about 9/10 of the additive TLVs) in the plant's general atmosphere during non-active periods of the work shift. Recommendations for improvement of working conditions and reduction of exposure levels are made. PMID:7055084

  19. The Pitcher Plant Sarracenia purpurea Can Directly Acquire Organic Nitrogen and Short-Circuit the Inorganic Nitrogen Cycle

    PubMed Central

    Karagatzides, Jim D.; Butler, Jessica L.; Ellison, Aaron M.

    2009-01-01

    Background Despite the large stocks of organic nitrogen in soil, nitrogen availability limits plant growth in many terrestrial ecosystems because most plants take up only inorganic nitrogen, not organic nitrogen. Although some vascular plants can assimilate organic nitrogen directly, only recently has organic nitrogen been found to contribute significantly to the nutrient budget of any plant. Carnivorous plants grow in extremely nutrient-poor environments and carnivory has evolved in these plants as an alternative pathway for obtaining nutrients. We tested if the carnivorous pitcher plant Sarracenia purpurea could directly take up intact amino acids in the field and compared uptake of organic and inorganic forms of nitrogen across a gradient of nitrogen deposition. We hypothesized that the contribution of organic nitrogen to the nitrogen budget of the pitcher plant would decline with increasing nitrogen deposition. Methodology and Principal Findings At sites in Canada (low nitrogen deposition) and the United States (high nitrogen deposition), individual pitchers were fed two amino acids, glycine and phenylalanine, and inorganic nitrogen (as ammonium nitrate), individually and in mixture. Plants took up intact amino acids. Acquisition of each form of nitrogen provided in isolation exceeded uptake of the same form in mixture. At the high deposition site, uptake of organic nitrogen was higher than uptake of inorganic nitrogen. At the low deposition site, uptake of all three forms of nitrogen was similar. Completeness of the associated detritus-based food web that inhabits pitcher-plant leaves and breaks down captured prey had no effect on nitrogen uptake. Conclusions and Significance By taking up intact amino acids, Sarracenia purpurea can short-circuit the inorganic nitrogen cycle, thus minimizing potential bottlenecks in nitrogen availability that result from the plant's reliance for nitrogen mineralization on a seasonally reconstructed food web operating on

  20. Powdered activated carbon coupled with enhanced coagulation for natural organic matter removal and disinfection by-product control: application in a Western Australian water treatment plant.

    PubMed

    Kristiana, Ina; Joll, Cynthia; Heitz, Anna

    2011-04-01

    The removal of organic precursors of disinfection by-products (DBPs), i.e. natural organic matter (NOM), prior to disinfection and distribution is considered as the most effective approach to minimise the formation of DBPs. This study investigated the impact of the addition of powdered activated carbon (PAC) to an enhanced coagulation treatment process at an existing water treatment plant on the efficiency of NOM removal, the disinfection behaviour of the treated water, and the water quality in the distribution system. This is the first comprehensive assessment of the efficacy of plant-scale application of PAC combined with enhanced coagulation on an Australian source water. As a result of the PAC addition, the removal of NOM improved by 70%, which led to a significant reduction (80-95%) in the formation of DBPs. The water quality in the distribution system also improved, indicated by lower concentrations of DBPs in the distribution system and better maintenance of disinfectant residual at the extremities of the distribution system. The efficacy of the PAC treatment for NOM removal was shown to be a function of the characteristics of the NOM and the quality of the source water, as well as the PAC dose. PAC treatment did not have the capacity to remove bromide ion, resulting in the formation of more brominated DBPs. Since brominated DBPs have been found to be more toxic than their chlorinated analogues, their preferential formation upon PAC addition must be considered, especially in source waters containing high concentrations of bromide. PMID:21353285

  1. Evaluation of the micronutrient composition of plant foods produced by organic and conventional agricultural methods.

    PubMed

    Hunter, Duncan; Foster, Meika; McArthur, Jennifer O; Ojha, Rachel; Petocz, Peter; Samman, Samir

    2011-07-01

    The aim of the present analysis was to evaluate the micronutrient content of plant foods produced by organic and conventional agricultural methods. Studies were identified from a search of electronic databases (1980-2007, inclusive) as well as manual searches. A total of 66 studies (describing 1440 micronutrient comparisons) were identified. Thirty-three studies (908 comparisons) satisfied the screening criteria which considered cultivar, harvesting, and soil conditions. In studies that satisfied the screening criteria, the absolute levels of micronutrients were higher in organic foods more often than in conventional foods (462 vs 364 comparisons, P=0.002), and the total micronutrient content, expressed as a percent difference, was higher in organic (+5.7%, P<0.001) as compared to conventionally grown produce. The micronutrient content of food groups was more frequently reported to be higher for organic vegetables and legumes compared to their conventional counterparts (vegetables, 267 vs 197, P<0.001; legumes, 79 vs 46, P=0.004). This trend was supported by a mean percent difference in micronutrient content favoring organic vegetables (+5.9%, P<0.001) and legumes (+5.7%, P<0.001). Further research is required to determine the effect of organic agricultural methods on a broader range of nutrients and their potential impact on health. PMID:21929333

  2. Identification of class B and class C floral organ identity genes from rice plants.

    PubMed

    Kang, H G; Jeon, J S; Lee, S; An, G

    1998-12-01

    The functions of two rice MADS-box genes were studied by the loss-of-function approach. The first gene, OsMADS4, shows a significant homology to members in the PISTILLATA (PI) family, which is required to specify petal and stamen identity. The second gene, OsMADS3, is highly homologous to the members in the AGAMOUS (AG) family that is essential for the normal development of the internal two whorls, the stamen and carpel, of the flower. These two rice MADS box cDNA clones were connected to the maize ubiquitin promoter in an antisense orientation and the fusion molecules were introduced to rice plants by the Agrobacterium-mediated transformation method. Transgenic plants expressing antisense OsMADS4 displayed alterations of the second and third whorls. The second-whorl lodicules, which are equivalent to the petals of dicot plants in grasses, were altered into palea/lemma-like organs, and the third whorl stamens were changed to carpel-like organs. Loss-of-function analysis of OsMADS3 showed alterations in the third and fourth whorls. In the third whorl, the filaments of the transgenic plants were changed into thick and fleshy bodies, similar to lodicules. Rather than making a carpel, the fourth whorl produced several abnormal flowers. These phenotypes are similar to those of the agamous and plena mutants in Arabidopsis and Antirrhinum, respectively. These results suggest that OsMADS4 belongs to the class B gene family and OsMADS3 belongs to the class C gene family of floral organ identity determination. PMID:9869408

  3. Assessment of distance-based multi-attribute group decision-making methods from a maintenance strategy perspective

    NASA Astrophysics Data System (ADS)

    Ding, Siew-Hong; Kamaruddin, Shahrul

    2015-07-01

    Maintenance has been acknowledged by industrial management as a significant influencing factor of plant performance. Effective plant maintenance can be realized by developing a proper maintenance strategy. However, selecting an appropriate maintenance strategy is difficult because maintenance is a non-repetitive task such as production activity. Maintenance also does not leave a consistent traceable record that can be referred to during the decision-making process. The involvement of tangible and intangible factors in the assessment process further increases the complexity of the decision-making process. The technique of preference order by similarity to ideal solution (TOPSIS) is one of the most well-known decision-making methods and has been widely used by organizations to conduct effective decisions regarding maintenance issues. TOPSIS has also evolved by integrating different approaches such as the fuzzy concept. Although numerous TOPSIS applications for maintenance decision making have been published, the effectiveness of crisp TOPSIS and fuzzy TOPSIS needs to be investigated further. This paper attempts to present a comparison between conventional crisp TOPSIS and fuzzy TOPSIS from a group maintenance decision-making perspective by an empirical illustration. Sensitivity analysis is conducted to demonstrate further the resilience of crisp TOPSIS and fuzzy TOPSIS.

  4. GENETIC CONTROL OF PLANT DEVELOPMENT GENETIC CONTROL OF PLANT DEVELOPMENT GENETIC CONTROL OF PLANT DEVELOPMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, several genes have been cloned that affect plant architecture: CLAVATA1, which controls the balance between maintenance and organogenesis in the meristem; CUC2, which separates organ primordia in the meristem; and teosinte branched 1 and cycloidea, which use growth suppression to cause mor...

  5. Stable isotope analysis of plant-derived nitrate - novel method for discrimination between organically and conventionally grown vegetables.

    PubMed

    Mihailova, A; Pedentchouk, N; Kelly, S D

    2014-07-01

    The lack of reliable markers for the discrimination between organic and conventional products makes the organic food market susceptible to attempted fraud. Robust analytical methodologies for organic food authentication are urgently needed. In this study a new approach, compound-specific nitrogen and oxygen isotope analysis of plant-derived nitrate, has been applied alongside bulk nitrogen isotope analysis for discrimination between organically and conventionally greenhouse-grown lettuce and retail potatoes and tomatoes. The method revealed significant differences between conventional and organic fertilisation. An intra-plant isotopic variation as well as significant impact of the fertiliser application rate on the nitrogen and oxygen isotope values of plant-derived nitrate has been observed. Nitrogen and oxygen isotope analysis of nitrate has a potential for differentiation between organic and conventional crops. Further analysis is needed to improve our understanding of the scope of application and robustness of this compound-specific approach. PMID:24518338

  6. Draft of new maintenance standards for LWR in Japan

    SciTech Connect

    Iida, Kunihiro

    1996-12-01

    Activities of development of new maintenance standards for operating nuclear power plant in Japan are described. The work of drafting the standards has been done by the Committee of Nuclear Plant Operation and Maintenance Standards (POMS), that was organized in the Japan Power Engineering and Inspection Corporation under the entrustment from the Ministry of International Trade and Industry. The articles of ASME Section XI related to inspection, flaw evaluation and repair have been examined and modified, if necessary, so as to introduce latest Japanese database and technological knowledge. In the area of repairs, many repair techniques verified in recent years in Japan were incorporated i n addition to those specified in ASME Section XI. Finally major differences between ASME Section XI and the draft of the standards are listed.

  7. Medicinal Plants and Other Living Organisms with Antitumor Potential against Lung Cancer

    PubMed Central

    Monteiro, Luara de Sousa; Bastos, Katherine Xavier; Barbosa-Filho, José Maria; de Athayde-Filho, Petrônio Filgueiras; Diniz, Margareth de Fátima Formiga Melo; Sobral, Marianna Vieira

    2014-01-01

    Lung cancer is a disease with high morbidity and mortality rates. As a result, it is often associated with a significant amount of suffering and a general decrease in the quality of life. Herbal medicines are recognized as an attractive approach to lung cancer therapy with little side effects and are a major source of new drugs. The aim of this work was to review the medicinal plants and other living organisms with antitumor potential against lung cancer. The assays were conducted with animals and humans, and Lewis lung carcinoma was the most used experimental model. China, Japan, South Korea, and Ethiopia were the countries that most published studies of species with antitumor activity. Of the 38 plants evaluated, 27 demonstrated antitumor activity. In addition, six other living organisms were cited for antitumor activity against lung cancer. Mechanisms of action, combination with chemotherapeutic drugs, and new technologies to increase activity and reduce the toxicity of the treatment are discussed. This review was based on the NAPRALERT databank, Web of Science, and Chemical Abstracts. This work shows that natural products from plants continue to be a rich source of herbal medicines or biologically active compounds against cancer. PMID:25147575

  8. Cross-talk between environmental stresses and plant metabolism during reproductive organ abscission

    PubMed Central

    Sawicki, Mélodie; Aït Barka, Essaïd; Clément, Christophe; Vaillant-Gaveau, Nathalie; Jacquard, Cédric

    2015-01-01

    In plants, flowering is a crucial process for reproductive success and continuity of the species through time. Fruit production requires the perfect development of reproductive structures. Abscission, a natural process, can occur to facilitate shedding of no longer needed, infected, or damaged organs. If stress occurs during flower development, abscission can intervene at flower level, leading to reduced yield. Flower abscission is a highly regulated developmental process simultaneously influenced and activated in response to exogenous (changing environmental conditions, interactions with microorganisms) and endogenous (physiological modifications) stimuli. During climate change, plant communities will be more susceptible to environmental stresses, leading to increased flower and fruit abscission, and consequently a decrease in fruit yield. Understanding the impacts of stress on the reproductive phase is therefore critical for managing future agricultural productivity. Here, current knowledge on flower/fruit abscission is summarized by focusing specifically on effects of environmental stresses leading to this process in woody plants. Many of these stresses impair hormonal balance and/or carbohydrate metabolism, but the exact mechanisms are far from completely known. Hormones are the abscission effectors and the auxin/ethylene balance is of particular importance. The carbohydrate pathway is the result of complex regulatory processes involving the balance between photosynthesis and mobilization of reserves. Hormones and carbohydrates together participate in complex signal transduction systems, especially in response to stress. The available data are discussed in relation to reproductive organ development and the process of abscission. PMID:25711702

  9. Cross-talk between environmental stresses and plant metabolism during reproductive organ abscission.

    PubMed

    Sawicki, Mélodie; Aït Barka, Essaïd; Clément, Christophe; Vaillant-Gaveau, Nathalie; Jacquard, Cédric

    2015-04-01

    In plants, flowering is a crucial process for reproductive success and continuity of the species through time. Fruit production requires the perfect development of reproductive structures. Abscission, a natural process, can occur to facilitate shedding of no longer needed, infected, or damaged organs. If stress occurs during flower development, abscission can intervene at flower level, leading to reduced yield. Flower abscission is a highly regulated developmental process simultaneously influenced and activated in response to exogenous (changing environmental conditions, interactions with microorganisms) and endogenous (physiological modifications) stimuli. During climate change, plant communities will be more susceptible to environmental stresses, leading to increased flower and fruit abscission, and consequently a decrease in fruit yield. Understanding the impacts of stress on the reproductive phase is therefore critical for managing future agricultural productivity. Here, current knowledge on flower/fruit abscission is summarized by focusing specifically on effects of environmental stresses leading to this process in woody plants. Many of these stresses impair hormonal balance and/or carbohydrate metabolism, but the exact mechanisms are far from completely known. Hormones are the abscission effectors and the auxin/ethylene balance is of particular importance. The carbohydrate pathway is the result of complex regulatory processes involving the balance between photosynthesis and mobilization of reserves. Hormones and carbohydrates together participate in complex signal transduction systems, especially in response to stress. The available data are discussed in relation to reproductive organ development and the process of abscission. PMID:25711702

  10. Vetiver grass, Vetiveria zizanioides: a choice plant for phytoremediation of heavy metals and organic wastes.

    PubMed

    Danh, Luu Thai; Truong, Paul; Mammucari, Raffaella; Tran, Tam; Foster, Neil

    2009-01-01

    Glasshouse and field studies showed that Vetiver grass can produce high biomass (>100t/ tha(-1) year(-1)) and highly tolerate extreme climatic variation such as prolonged drought, flood, submergence and temperatures (-15 degrees - 55 degrees C), soils high in acidity and alkalinity (pH 3.3-9.5), high levels of Al (85% saturation percentage), Mn (578 mg kg(-1)), soil salinity (ECse 47.5 dS m(-1)), sodicity (ESP 48%), anda wide range of heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Se, and Zn). Vetiver can accumulate heavy metals, particularly lead (shoot 0.4% and root 1%) and zinc (shoot and root 1%). The majority of heavy metals are accumulated in roots thus suitable for phytostabilization, and for phytoextraction with addition of chelating agents. Vetiver can also absorb and promote biodegradation of organic wastes (2,4,6-trinitroluene, phenol, ethidium bromide, benzo[a]pyrene, atrazine). Although Vetiver is not as effective as some other species in heavy metal accumulation, very few plants in the literature have a wide range of tolerance to extremely adverse conditions of climate and growing medium (soil, sand, and railings) combined into one plant as vetiver. All these special characteristics make vetiver a choice plant for phytoremediation of heavy metals and organic wastes. PMID:19810597

  11. The PsbW protein stabilizes the supramolecular organization of photosystem II in higher plants.

    PubMed

    García-Cerdán, José G; Kovács, Laszlo; Tóth, Tünde; Kereïche, Sami; Aseeva, Elena; Boekema, Egbert J; Mamedov, Fikret; Funk, Christiane; Schröder, Wolfgang P

    2011-02-01

    PsbW, a 6.1-kDa low-molecular-weight protein, is exclusive to photosynthetic eukaryotes, and associates with the photosystem II (PSII) protein complex. In vivo and in vitro comparison of Arabidopsis thaliana wild-type plants with T-DNA insertion knock-out mutants completely lacking the PsbW protein, or with antisense inhibition plants exhibiting decreased levels of PsbW, demonstrated that the loss of PsbW destabilizes the supramolecular organization of PSII. No PSII-LHCII supercomplexes could be detected or isolated in the absence of the PsbW protein. These changes in macro-organization were accompanied by a minor decrease in the chlorophyll fluorescence parameter F(V) /F(M) , a strongly decreased PSII core protein phosphorylation and a modification of the redox state of the plastoquinone (PQ) pool in dark-adapted leaves. In addition, the absence of PsbW protein led to faster redox changes in the PQ pool, i.e. transitions from state 1 to state 2, as measured by changes in stationary fluorescence (F(S) ) kinetics, compared with the wild type. Despite these dramatic effects on macromolecular structure, the transgenic plants exhibited no significant phenotype under normal growth conditions. We suggest that the PsbW protein is located close to the minor antenna of the PSII complex, and is important for the contact and stability between several PSII-LHCII supercomplexes. PMID:21265891

  12. Marsh plant response to metals: Exudation of aliphatic low molecular weight organic acids (ALMWOAs)

    NASA Astrophysics Data System (ADS)

    Rocha, A. Cristina S.; Almeida, C. Marisa R.; Basto, M. Clara P.; Vasconcelos, M. Teresa S. D.

    2016-03-01

    Metal exposure is known to induce the production and secretion of substances, such as aliphatic low molecular weight organic acids (ALMWOAs), into the rhizosphere by plant roots. Knowledge on this matter is extensive for soil plants but still considerably scarce regarding marsh plants roots adapted to high salinity media. Phragmites australis and Halimione portulacoides, two marsh plants commonly distributed in European estuarine salt marshes, were used to assess the response of roots of both species, in terms of ALMWOAs exudation, to Cu, Ni and Cd exposure (isolated and in mixture since in natural environment, they are exposed to mixture of metals). As previous studies were carried out in unrealistic and synthetic media, here a more natural medium was selected. Therefore, in vitro experiments were carried out, with specimens of both marsh plants, and in freshwater contaminated with two different Cu, Ni and Cd concentrations (individual metal and in mixture). Both marsh plants were capable of liberating ALMWOAs into the surrounding medium. Oxalic, citric and maleic acids were found in P. australis root exudate solutions and oxalic and maleic acids in H. portulacoides root exudate solutions. ALMWOA liberation by both plants was plant species and metal-dependent. For instance, Cu affected the exudation of oxalic acid by H. portulacoides and of oxalic and citric acids by P. australis roots. In contrast, Ni and Cd did not stimulate any specific response. Regarding the combination of all metals, H. portulacoides showed a similar response to that observed for Cu individually. However, in the P. australis case, at high metal concentration mixture, a synergetic effect led to the increase of oxalic acid levels in root exudate solution and to a decrease of citric acid liberation. A correlation between ALMWOAs exudation and metal accumulation could not be established. P. australis and H. portulacoides are considered suitable metal phytoremediators of estuarine impacted areas

  13. Characterization of organic matter of plants from lakes by thermal analysis in a N2 atmosphere.

    PubMed

    Guo, Fei; Wu, Fengchang; Mu, Yunsong; Hu, Yan; Zhao, Xiaoli; Meng, Wei; Giesy, John P; Lin, Ying

    2016-01-01

    Organic matter (OM) has been characterized using thermal analysis in O2 atmospheres, but it is not clear if OM can be characterized using slow thermal degradation in N2 atmospheres (STDN). This article presents a new method to estimate the behavior of OM in anaerobic environment. Seventeen different plants from Tai Lake (Ch: Taihu), China were heated to 600 °C at a rate of 10 °C min(-1) in a N2 atmosphere and characterized by use of differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). DSC chromatograms were compared with 9 standard compounds. Seven peaks were observed in DSC chromatograms, 2 main peaks strongly correlated with biochemical indices, and one main peak was a transitional stage. Energy absorbed by a peak at approximately 200 °C and total organic carbon were well correlated, while energy absorbed at approximately 460 °C was negatively correlated with lignin content. Presence of peaks at approximately 350 and 420 °C varied among plant biomass sources, providing potential evidence for biomass identification. Methods of STDN reported here were rapid and accurate ways to quantitatively characterize OM, which may provide useful information for understanding anaerobic behaviors of natural organic matters. PMID:26953147

  14. Characterization of organic matter of plants from lakes by thermal analysis in a N2 atmosphere

    NASA Astrophysics Data System (ADS)

    Guo, Fei; Wu, Fengchang; Mu, Yunsong; Hu, Yan; Zhao, Xiaoli; Meng, Wei; Giesy, John P.; Lin, Ying

    2016-03-01

    Organic matter (OM) has been characterized using thermal analysis in O2 atmospheres, but it is not clear if OM can be characterized using slow thermal degradation in N2 atmospheres (STDN). This article presents a new method to estimate the behavior of OM in anaerobic environment. Seventeen different plants from Tai Lake (Ch: Taihu), China were heated to 600 °C at a rate of 10 °C min‑1 in a N2 atmosphere and characterized by use of differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). DSC chromatograms were compared with 9 standard compounds. Seven peaks were observed in DSC chromatograms, 2 main peaks strongly correlated with biochemical indices, and one main peak was a transitional stage. Energy absorbed by a peak at approximately 200 °C and total organic carbon were well correlated, while energy absorbed at approximately 460 °C was negatively correlated with lignin content. Presence of peaks at approximately 350 and 420 °C varied among plant biomass sources, providing potential evidence for biomass identification. Methods of STDN reported here were rapid and accurate ways to quantitatively characterize OM, which may provide useful information for understanding anaerobic behaviors of natural organic matters.

  15. Characterization of organic matter of plants from lakes by thermal analysis in a N2 atmosphere

    PubMed Central

    Guo, Fei; Wu, Fengchang; Mu, Yunsong; Hu, Yan; Zhao, Xiaoli; Meng, Wei; Giesy, John P.; Lin, Ying

    2016-01-01

    Organic matter (OM) has been characterized using thermal analysis in O2 atmospheres, but it is not clear if OM can be characterized using slow thermal degradation in N2 atmospheres (STDN). This article presents a new method to estimate the behavior of OM in anaerobic environment. Seventeen different plants from Tai Lake (Ch: Taihu), China were heated to 600 °C at a rate of 10 °C min−1 in a N2 atmosphere and characterized by use of differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). DSC chromatograms were compared with 9 standard compounds. Seven peaks were observed in DSC chromatograms, 2 main peaks strongly correlated with biochemical indices, and one main peak was a transitional stage. Energy absorbed by a peak at approximately 200 °C and total organic carbon were well correlated, while energy absorbed at approximately 460 °C was negatively correlated with lignin content. Presence of peaks at approximately 350 and 420 °C varied among plant biomass sources, providing potential evidence for biomass identification. Methods of STDN reported here were rapid and accurate ways to quantitatively characterize OM, which may provide useful information for understanding anaerobic behaviors of natural organic matters. PMID:26953147

  16. [Source emission characteristics and impact factors of volatile halogenated organic compounds from wastewater treatment plant].

    PubMed

    He, Jie; Wang, Bo-Guang; Liu, Shu-Le; Zhao, De-Jun; Tang, Xiao-Dong; Zou, Yu

    2011-12-01

    A low enrichment method of using Tenax as absorbent and liquid nitrogen as refrigerant has been established to sample the volatile halogenated organic compounds in Guangzhou Liede municipal wastewater treatment plant as well as its ambient air. The composition and concentration of target halogenated hydrocarbons were analyzed by combined thermal desorption/GC-MS to explore its sources profile and impact factors. The result showed that 19 halogenated organic compounds were detected, including 11 halogenated alkanets, 3 halogenated alkenes, 3 halogenated aromatic hydrocarbons and 2 haloesters, with their total concentrations ranged from 34.91 microg x m(-3) to 127.74 microg x m(-3) and mean concentrations ranged from n.d. to 33.39 microg x m(-3). Main pollutants of the studied plant were CH2Cl2, CHCl3, CFC-12, C2H4Cl2, CFC-11, C2HCl3 and C2Cl4, they came from the wastewater by volatilization. Among the six processing units, the dehydration room showed the highest level of halogenated organic compounds, followed by pumping station, while the sludge thickener was the lowest. The emissions from pumping station, aeration tank and biochemical pool were significantly affected by temperature and humidity of environment. PMID:22468521

  17. Thermochemical pretreatments of organic fraction of municipal solid waste from a mechanical-biological treatment plant.

    PubMed

    Álvarez-Gallego, Carlos José; Fdez-Güelfo, Luis Alberto; de los Ángeles Romero Aguilar, María; Romero García, Luis Isidoro

    2015-01-01

    The organic fraction of municipal solid waste (OFMSW) usually contains high lignocellulosic and fatty fractions. These fractions are well-known to be a hard biodegradable substrate for biological treatments and its presence involves limitations on the performance of anaerobic processes. To avoid this, thermochemical pretreatments have been applied on the OFMSW coming from a full-scale mechanical-biological treatment (MBT) plant, in order to pre-hydrolyze the waste and improve the organic matter solubilisation. To study the solubilisation yield, the increments of soluble organic matter have been measured in terms of dissolved organic carbon (DOC), soluble chemical oxygen demand (sCOD), total volatile fatty acids (TVFA) and acidogenic substrate as carbon (ASC). The process variables analyzed were temperature, pressure and NaOH dosage. The levels of work for each variable were three: 160-180-200 °C, 3.5-5.0-6.5 bar and 2-3-4 g NaOH/L. In addition, the pretreatment time was also modified among 15 and 120 min. The best conditions for organic matter solubilisation were 160 °C, 3 g NaOH/L, 6.5 bar and 30 min, with yields in terms of DOC, sCOD, TVFA and ASC of 176%, 123%, 119% and 178% respectively. Thus, predictably the application of this pretreatment in these optimum conditions could improve the H2 production during the subsequent Dark Fermentation process. PMID:25671816

  18. Thermochemical Pretreatments of Organic Fraction of Municipal Solid Waste from a Mechanical-Biological Treatment Plant

    PubMed Central

    Álvarez-Gallego, Carlos José; Fdez-Güelfo, Luis Alberto; Romero Aguilar, María de los Ángeles; Romero García, Luis Isidoro

    2015-01-01

    The organic fraction of municipal solid waste (OFMSW) usually contains high lignocellulosic and fatty fractions. These fractions are well-known to be a hard biodegradable substrate for biological treatments and its presence involves limitations on the performance of anaerobic processes. To avoid this, thermochemical pretreatments have been applied on the OFMSW coming from a full-scale mechanical-biological treatment (MBT) plant, in order to pre-hydrolyze the waste and improve the organic matter solubilisation. To study the solubilisation yield, the increments of soluble organic matter have been measured in terms of dissolved organic carbon (DOC), soluble chemical oxygen demand (sCOD), total volatile fatty acids (TVFA) and acidogenic substrate as carbon (ASC). The process variables analyzed were temperature, pressure and NaOH dosage. The levels of work for each variable were three: 160–180–200 °C, 3.5–5.0–6.5 bar and 2–3–4 g NaOH/L. In addition, the pretreatment time was also modified among 15 and 120 min. The best conditions for organic matter solubilisation were 160 °C, 3 g NaOH/L, 6.5 bar and 30 min, with yields in terms of DOC, sCOD, TVFA and ASC of 176%, 123%, 119% and 178% respectively. Thus, predictably the application of this pretreatment in these optimum conditions could improve the H2 production during the subsequent Dark Fermentation process. PMID:25671816

  19. First complete chromosomal organization of a protozoan plant parasite (Phytomonas spp.).

    PubMed

    Marín, Clotilde; Alberge, Blandine; Dollet, Michel; Pagès, Michel; Bastien, Patrick

    2008-01-01

    Phytomonas spp. are members of the family Trypanosomatidae that parasitize plants and may cause lethal diseases in crops such as Coffee Phloem necrosis, Hartrot in coconut, and Marchitez sorpresiva in oil palm. In this study, the molecular karyotype of 6 isolates from latex plants has been entirely elucidated by pulsed-field gel electrophoresis and DNA hybridization. Twenty-one chromosomal linkage groups constituting heterologous chromosomes and sizing between 0.3 and 3 Mb could be physically defined by the use of 75 DNA markers (sequence-tagged sites and genes). From these data, the genome size can be estimated at 25.5 (+/-2) Mb. The physical linkage groups were consistently conserved in all strains examined. Moreover, the finding of several pairs of different-sized homologous chromosomes strongly suggest diploidy for this organism. The definition of the complete molecular karyotype of Phytomonas represents an essential primary step toward sequencing the genome of this parasite of economical importance. PMID:18031984

  20. Biosafety research for non-target organism risk assessment of RNAi-based GE plants

    PubMed Central

    Roberts, Andrew F.; Devos, Yann; Lemgo, Godwin N. Y.; Zhou, Xuguo

    2015-01-01

    RNA interference, or RNAi, refers to a set of biological processes that make use of conserved cellular machinery to silence genes. Although there are several variations in the source and mechanism, they are all triggered by double stranded RNA (dsRNA) which is processed by a protein complex into small, single stranded RNA, referred to as small interfering RNAs (siRNA) with complementarity to sequences in genes targeted for silencing. The use of the RNAi mechanism to develop new traits in plants has fueled a discussion about the environmental safety of the technology for these applications, and this was the subject of a symposium session at the 13th ISBGMO in Cape Town, South Africa. This paper continues that discussion by proposing research areas that may be beneficial for future environmental risk assessments of RNAi-based genetically modified plants, with a particular focus on non-target organism assessment. PMID:26594220

  1. Biosafety research for non-target organism risk assessment of RNAi-based GE plants.

    PubMed

    Roberts, Andrew F; Devos, Yann; Lemgo, Godwin N Y; Zhou, Xuguo

    2015-01-01

    RNA interference, or RNAi, refers to a set of biological processes that make use of conserved cellular machinery to silence genes. Although there are several variations in the source and mechanism, they are all triggered by double stranded RNA (dsRNA) which is processed by a protein complex into small, single stranded RNA, referred to as small interfering RNAs (siRNA) with complementarity to sequences in genes targeted for silencing. The use of the RNAi mechanism to develop new traits in plants has fueled a discussion about the environmental safety of the technology for these applications, and this was the subject of a symposium session at the 13th ISBGMO in Cape Town, South Africa. This paper continues that discussion by proposing research areas that may be beneficial for future environmental risk assessments of RNAi-based genetically modified plants, with a particular focus on non-target organism assessment. PMID:26594220

  2. 18. Walkway between maintenance building and office building along south ...

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

    18. Walkway between maintenance building and office building along south side of main plant looking east - Skinner Meat Packing Plant, Main Plant, 6006 South Twenty-seventh Street, Omaha, Douglas County, NE

  3. Effects of different forms of plant-derived organic matter on nitrous oxide emissions.

    PubMed

    Qiu, Qingyan; Wu, Lanfang; Ouyang, Zhu; Li, Binbin; Xu, Yanyan

    2016-07-13

    To investigate the impact of different forms of plant-derived organic matter on nitrous oxide (N2O) emissions, an incubation experiment with the same rate of total nitrogen (N) application was carried out at 25 °C for 250 days. Soils were incorporated with maize-derived organic matter (i.e., maize residue-derived dissolved organic matter and maize residues with different C/N ratios) and an inorganic N fertilizer (urea). The pattern and magnitude of nitrous oxide (N2O) emissions were affected by the form of N applied. Single application of maize-derived organic matter resulted in a higher N2O emission than single application of the inorganic N fertilizer or combined application of the inorganic N fertilizer and maize-derived organic matter. The positive effect of maize residue-derived dissolved organic matter (DOM) addition on N2O emissions was relatively short-lived and mainly occurred at the early stage following DOM addition. In contrast, the positive effect induced by maize residue addition was more pronounced and lasted for a longer period. Single application of maize residues resulted in a substantial decrease in soil nitric nitrogen (NO3(-)-N), but it did not affect the production of N2O. No significant relationship between N2O emission and NO3(-)-N and ammonium nitrogen (NH4(+)-N) suggested that the availability of soil N was not limiting the production of N2O in our study. The key factors affecting soil N2O emission were the soil dissolved organic carbon (DOC) content and metabolism quotient (qCO2). Both of them could explain 87% of the variation in cumulative N2O emission. The C/N ratio of maize-derived organic matter was a poor predictor of N2O emission when the soil was not limited by easily available C and the available N content met the microbial N demands for nitrification and denitrification. The results suggested that the magnitude of N2O emission was determined by the impact of organic amendments on soil C availability and microbial activity

  4. K+ uptake in plant roots. The systems involved, their regulation and parallels in other organisms.

    PubMed

    Nieves-Cordones, Manuel; Alemán, Fernando; Martínez, Vicente; Rubio, Francisco

    2014-05-15

    Potassium (K(+)) is an essential macronutrient for plants. It is taken into the plant by the transport systems present in the plasma membranes of root epidermal and cortical cells. The identity of these systems and their regulation is beginning to be understood and the systems of K(+) transport in the model species Arabidopsis thaliana remain far better characterized than in any other plant species. Roots can activate different K(+) uptake systems to adapt to their environment, important to a sessile organism that needs to cope with a highly variable environment. The mechanisms of K(+) acquisition in the model species A. thaliana are the best characterized at the molecular level so far. According to the current model, non-selective channels are probably the main pathways for K(+) uptake at high concentrations (>10mM), while at intermediate concentrations (1mM), the inward rectifying channel AKT1 dominates K(+) uptake. Under lower concentrations of external K(+) (100μM), AKT1 channels, together with the high-affinity K(+) uptake system HAK5 contribute to K(+) acquisition, and at extremely low concentrations (<10μM) the only system capable of taking up K(+) is HAK5. Depending on the species the high-affinity system has been named HAK5 or HAK1, but in all cases it fulfills the same functions. The activation of these systems as a function of the K(+) availability is achieved by different mechanisms that include phosphorylation of AKT1 or induction of HAK5 transcription. Some of the characteristics of the systems for root K(+) uptake are shared by other organisms, whilst others are specific to plants. This indicates that some crucial properties of the ancestral of K(+) transport systems have been conserved through evolution while others have diverged among different kingdoms. PMID:24810767

  5. Plant-Microbial Interactions Define Potential Mechanisms of Organic Matter Priming in the Rhizosphere

    NASA Astrophysics Data System (ADS)

    Zhalnina, K.; Cho, H. J.; Hao, Z.; Mansoori, N.; Karaoz, U.; Jenkins, S.; White, R. A., III; Lipton, M. S.; Deng, K.; Zhou, J.; Pett-Ridge, J.; Northen, T.; Firestone, M. K.; Brodie, E.

    2015-12-01

    In the rhizosphere, metabolic processes of plants and microorganisms are closely coupled, and together with soil minerals, their interactions regulate the turnover of soil organic C (SOC). Plants provide readily assimilable metabolites for microorganisms through exudation, and it has been hypothesized that increasing concentrations of exudate C may either stimulate or suppress rates of SOC mineralization (rhizosphere priming). Both positive and negative rhizosphere priming has been widely observed, however the underlying mechanisms remain poorly understood. To begin to identify the molecular mechanisms underlying rhizosphere priming, we isolated a broad range of soil bacteria from a Mediterranean grassland dominated by annual grass. Thirty-nine heterotrophic bacteria were selected for genome sequencing and both rRNA gene analysis and metagenome coverage suggest that these isolates represent naturally abundant strain variants. We analyzed their genomes for potential metabolic traits related to life in the rhizosphere and the decomposition of polymeric SOC. While the two dominant groups, Alphaproteobacteria and Actinobacteria, were enriched in polymer degrading enzymes, Alphaproteobacterial isolates contained greater gene copies of transporters related to amino acid, organic acid and auxin uptake or export, suggesting an enhanced metabolic potential for life in the root zone. To verify this metabolic potential, we determined the enzymatic activities of these isolates and revealed preferences of strains to degrade certain polymers (xylan, cellulose or lignin). Fourier Transform Infrared spectroscopy is being used to determine which polymeric components of plant roots are targeted by specific strains and how exudates may impact their degradation. To verify the potential of isolates to assimilate root exudates and export key metabolites we are using LC-MS/MS based exometabolomic profiling. The traits hypothesized and verified here (transporters, enzymes, exudate uptake

  6. Hazardous organic compounds in biogas plant end products--soil burden and risk to food safety.

    PubMed

    Suominen, K; Verta, M; Marttinen, S

    2014-09-01

    The end products (digestate, solid fraction of the digestate, liquid fraction of the digestate) of ten biogas production lines in Finland were analyzed for ten hazardous organic compounds or compound groups: polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polychlorinated biphenyls (PCB(7)), polyaromatic hydrocarbons (PAH(16)), bis-(2-ethylhexyl) phthalate (DEHP), perfluorinated alkyl compounds (PFCs), linear alkylbenzene sulfonates (LASs), nonylphenols and nonylphenol ethoxylates (NP+NPEOs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA). Biogas plant feedstocks were divided into six groups: municipal sewage sludge, municipal biowaste, fat, food industry by-products, animal manure and others (consisting of milling by-products (husk) and raw former foodstuffs of animal origin from the retail trade). There was no clear connection between the origin of the feedstocks of a plant and the concentrations of hazardous organic compounds in the digestate. For PCDD/Fs and for DEHP, the median soil burden of the compound after a single addition of digestate was similar to the annual atmospheric deposition of the compound or compound group in Finland or other Nordic countries. For PFCs, the median soil burden was somewhat lower than the atmospheric deposition in Finland or Sweden. For NP+NPEOs, the soil burden was somewhat higher than the atmospheric deposition in Denmark. The median soil burden of PBDEs was 400 to 1000 times higher than the PBDE air deposition in Finland or in Sweden. With PBDEs, PFCs and HBCD, the impact of the use of end products should be a focus of further research. Highly persistent compounds, such as PBDE- and PFC-compounds may accumulate in agricultural soil after repeated use of organic fertilizers containing these compounds. For other compounds included in this study, agricultural use of biogas plant end products is unlikely to cause risk to food safety in Finland. PMID:24593894

  7. Black Nitrogen or Plant-Derived Organic Nitrogen - which Form is More Efficiently Sequestered in Soils?

    NASA Astrophysics Data System (ADS)

    López-Martín, María; Velasco-Molina, Marta; Knicker, Heike

    2014-05-01

    Input of charcoal after forest fires can lead to considerable changes of the quality and quantity of organic matter in soils (SOM). This affects not only its organic C pool but also shifts its organic N composition from peptideous to N-heterocyclic structures (Knicker et al., 1996). In the present study we sought to understand how this alteration is affecting the N availability in fire affected soils. Therefore, we performed a medium-term pot experiment in which grass material (Lolium perenne) was grown on soil material (Cambisols) of a fire-affected and a fire-unaffected forest. The soils were topped with mixtures of ground fresh grass residues and KNO3 or charred grass material (pyrogenic organic matter; PyOM) with KNO3. Here, either the organic N or the inorganic N was isotopically enriched with 15N. Following the 15N concentration in the soil matrix and the growing plants as a function of incubation time (up to 16 months) by isotopic ratio mass spectrometry allowed us to indentify which N-source is most efficiently stabilized and how PyOM is affecting this process. Preliminary data indicated that only after the germination of the seeds, the concentration of the added inorganic 15N in the soil decreased considerably most likely due to its uptake by the growing plants but also due to N-losses by leaching and volatilization. Additional addition of plant residues or PyOM had no major effect on this behavior. Covering the soil with 15N-grass residues which simulates a litter layer led to a slow increase of the 15N concentration in the mineral soil during the first month. This is best explained by the ongoing incorporation of the litter into the soil matrix. After that a small decrease was observed, showing that the organic N was only slowly mobilized. Addition of 15N-PyOM showed a comparable behavior but with 15N concentration in the soil corresponding to twice of those of the pots amended with 15N-grass residues. After that the 15N concentrations decrease quickly

  8. PFP MICON maintenance manual. Revision 1

    SciTech Connect

    Silvan, G.R.

    1995-01-25

    This manual covers the use of maintenance displays, maintenance procedures, system alarms and common system failures. This manual is intended to supplement the MICON maintenance training not replace it. It also assumes that the user is familiar with the normal operation of the MICON A/S system. The MICON system is a distributed control computer and, among other things, controls the HVAC system for the Plutonium Finishing Plant.

  9. Plant growth-promoting rhizobacteria strain Bacillus amyloliquefaciens NJN-6-enriched bio-organic fertilizer suppressed Fusarium wilt and promoted the growth of banana plants.

    PubMed

    Yuan, Jun; Ruan, Yunze; Wang, Beibei; Zhang, Jian; Waseem, Raza; Huang, Qiwei; Shen, Qirong

    2013-04-24

    Bacillus amyloliquefaciens strain NJN-6 is an important plant growth-promoting rhizobacteria (PGPR) which can produce secondary metabolites antagonistic to several soil-borne pathogens. In this study, the ability of a bio-organic fertilizer (BIO) containing NJN-6 strain to promote the growth and suppress Fusarium wilt of banana plants was evaluated in a pot experiment. The results showed that the application of BIO significantly decreased the incidence of Fusarium wilt and promoted the growth of banana plants compared to that for the organic fertilizer (OF). To determine the beneficial mechanism of the strain, the colonization of NJN-6 strain on banana roots was evaluated using scanning electron microscopy (SEM). The plant growth-promoting hormones indole-3-acetic acid (IAA) and gibberellin A3 (GA3), along with antifungal lipopeptides iturin A, were detected when the NJN-6 strain was incubated in both Landy medium with additional l-tryptophan and in root exudates of banana plants. In addition, some antifungal volatile organic compounds and iturin A were also detected in BIO. In summary, strain NJN-6 could colonize the roots of banana plants after the application of BIO and produced active compounds which were beneficial for the growth of banana plants. PMID:23541032

  10. A three step approach for removing organic matter from South African water sources and treatment plants

    NASA Astrophysics Data System (ADS)

    Nkambule, T. I.; Krause, R. W. M.; Haarhoff, J.; Mamba, B. B.

    The high variability in the levels and composition of natural organic matter (NOM) in South-African water sources in different regions means that no single treatment process can be prescribed for each water treatment plant operating in the country. In order to remove NOM from water in a water treatment train, the composition of the NOM in the source water must be taken into account, especially as it may not necessarily be uniform since the composition is dependent on local environmental situation. The primary objective of this study was to characterise the NOM present in South African source waters through an extensive sampling of representative water types across the country and then develop a rapid NOM characterisation protocol. Water samples were thus collected from eight different water treatment plants located throughout the country at different sites of their water treatment trains. Raw water samples, the intermediate samples before filtration and water samples before disinfection were collected at these drinking water treatment plants. The fluorescence excitation-emission matrices (FEEMs), biodegradable dissolved organic carbon (BDOC), ultraviolet (UV) characterisation (200-900 nm) and dissolved organic carbon (DOC) analysis were used to characterise the NOM in the water samples. The FEEM and UV results revealed that the samples were composed mainly of humic substances with a high UV-254 absorbance, while some samples had marine humic substances and non-humic substances. The sample’s DOC results were within the range of 3.25-21.44 mg C/L, which was indicative of the varying nature of the NOM composition in the regions where samples were obtained. The BDOC fraction of the NOM, on the other hand, ranged from 20% to 65%, depending on the geographical location of the sampling site. It is evident from the results obtained that the NOM composition varied per sampling site which would eventually have a bearing on its treatability. The various water treatment

  11. The improvement of removal effects on organic pollutants in Wastewater Treatment Plants (WWTP)

    NASA Astrophysics Data System (ADS)

    Marincas, O.; Petrov, P.; Ternes, T.; Avram, V.; Moldovan, Z.

    2009-08-01

    Purpose of this study is to improve the efficiency of removal in wastewater treatment plants of some organic pollutants like pharmaceuticals, antioxidants, pesticides (triazines, phenylurea herbicides), personal care products (PCPs) musk fragrances (galaxolide and tonalide) and estrogens using zeolites with excellent absorption capacity. The zeolite selected for all experiments was Szedimentin-MW. The experiment took place in three stages: no zeolite addition, zeolite added at the end of the bioreactor and zeolite added at the start of the bioreactor. The water samples were pre-concentrated with solid phase extraction (SPE) procedure and analyzed with analytical system Gas Chromatography/Mass Spectrometry (GC/MS).

  12. The carbon isotope composition of ancient CO2 based on higher-plant organic matter.

    PubMed

    Gröcke, Darren R

    2002-04-15

    Carbon isotope ratios in higher-plant organic matter (delta(13)C(plant)) have been shown in several studies to be closely related to the carbon isotope composition of the ocean-atmosphere carbon reservoir, and, in particular, the isotopic composition of CO(2). These studies have primarily been focused on geological intervals in which major perturbations occur in the oceanic carbon reservoir, as documented in organic carbon and carbonates phases (e.g. Permian-Triassic and Triassic-Jurassic boundary, Early Toarcian, Early Aptian, Cenomanian-Turonian boundary, Palaeocene-Eocene Thermal Maximum (PETM)). All of these events, excluding the Cenomanian-Turonian boundary, record negative carbon isotope excursions, and many authors have postulated that the cause of such excursions is the massive release of continental-margin marine gas-hydrate reservoirs (clathrates). Methane has a very negative carbon isotope composition (delta(13)C, ca. 60 per thousand ) in comparison with higher-plant and marine organic matter, and carbonate. The residence time of methane in the ocean-atmosphere reservoir is short (ca. 10 yr) and is rapidly oxidized to CO(2), causing the isotopic composition of CO(2) to become more negative from its assumed background value (delta(13)C, ca. -7 per thousand ). However, to date, only the Early Toarcian, Early Aptian and PETM are well-constrained chronometric sequences that could attribute clathrate release as a viable cause to create such rapid negative delta(13)C excursions. Notwithstanding this, the isotopic analysis of higher-plant organic matter (e.g. charcoal, wood, leaves, pollen) has the ability to (i) record the isotopic composition of palaeoatmospheric CO(2) in the geological record, (ii) correlate marine and non-marine stratigraphic successions, and (iii) confirm that oceanic carbon perturbations are not purely oceanographic in their extent and affect the entire ocean-atmosphere system. A case study from the Isle of Wight, UK, indicates that the

  13. Resolving the 'nitrogen paradox' of arbuscular mycorrhizas: fertilization with organic matter brings considerable benefits for plant nutrition and growth.

    PubMed

    Thirkell, Tom J; Cameron, Duncan D; Hodge, Angela

    2016-08-01

    Arbuscular mycorrhizal fungi (AMF) can transfer nitrogen (N) to host plants, but the ecological relevance is debated, as total plant N and biomass do not generally increase. The extent to which the symbiosis is mutually beneficial is thought to rely on the stoichiometry of N, phosphorus (P) and carbon (C) availability. While inorganic N fertilization has been shown to elicit strong mutualism, characterized by improved plant and fungal growth and mineral nutrition, similar responses following organic N addition are lacking. Using a compartmented microcosm experiment, we determined the significance to a mycorrhizal plant of placing a (15) N-labelled, nitrogen-rich patch of organic matter in a compartment to which only AMF hyphae had access. Control microcosms denied AMF hyphal access to the patch compartment. When permitted access to the patch compartment, the fungus proliferated extensively in the patch and transferred substantial quantities of N to the plant. Moreover, our data demonstrate that allowing hyphal access to an organic matter patch enhanced total plant N and P contents, with a simultaneous and substantial increase in plant biomass. Furthermore, we demonstrate that organic matter fertilization of arbuscular mycorrhizal plants can foster a mutually beneficial symbiosis based on nitrogen transfer, a phenomenon previously thought irrelevant. PMID:26510552

  14. Influence of biochar and plant growth on organic matter dynamics in a reclaimed mine residue

    NASA Astrophysics Data System (ADS)

    Moreno-Barriga, Fabián; Díaz, Vicente; Alberto, Jose; Faz, Ángel; Zornoza, Raúl

    2016-04-01

    This study aims at assessing the impact of biochar and marble waste amendment and the development of vegetation in acidic mine wastes on organic matter dynamics. For this purpose, a mine residue was collected in a tailing pond from the Sierra Minera of Cartagena-La Unión (SE Spain), and a greenhouse experiment was established for 120 days. Marble waste (MW) was added in a rate of 200 g kg-1 as a source of calcium carbonate to increase the pH from 3 to 7.5-8 (average pH in the native soils of the area). We added biochar as a source of organic carbon and nutrients, in two different rates, 50 g kg-1 (BC1) and 100 g kg-1 (BC2). To assess the influence of vegetation growth on the creation of a technosoil from mine residues and its impact on organic matter dynamics, the plant species Piptatherum miliaceum (PM) was planted in half the pots with the different amendments. Thus, five treatments were established: unamended and unplanted control (CT), BC1, BC2, BC1+PM and BC2+PM. Results showed that the different treatments had no significant effect on aggregates stability, microbial biomass carbon and the emission of N2O and CH4. So, it seems that longer periods are needed to increase the stability of aggregates and microbial populations, since even the combined use of biochar, marble waste and vegetation was not enough to increase these properties in 120 days. Nonetheless, it was positive that the addition of biochar and the release of root exudates did not trigger the emission of greenhouse gases. Organic carbon significantly increased with the addition of biochar, with values similar to the dose applied, indicating high stability and low mineralization of the amendment. The addition of amendments significantly increased arylesterase activity, while the growth of the plant was needed to significantly increase β-glucosidase activity. The soluble carbon significantly decreased in BC1 and BC2 with regards to CT, while no significant differences were observed among CT and

  15. HPLC-Profiles of Tocopherols, Sugars, and Organic Acids in Three Medicinal Plants Consumed as Infusions.

    PubMed

    Roriz, Custódio Lobo; Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C F R

    2014-01-01

    Pterospartum tridentatum (L.) Willk, Gomphrena globosa L., and Cymbopogon citratus (DC.) Stapf are medicinal plants that require a more detailed chemical characterization, given the importance of their consumption as infusions. Therefore, the individual profiles in tocopherols, free sugars, and organic acids were obtained by high performance liquid chromatography (HPLC) coupled to different detectors (fluorescence, refraction index, and photodiode array, resp.). C. citratus revealed the highest content of α-, and total tocopherols, glucose, sucrose, succinic, and ascorbic acids. P. tridentatum presented the highest fructose and total sugars content. Otherwise, G. globosa showed the highest organic acids concentration. As far as we know, this is the first study reporting the mentioned chemical compounds in G. globosa and C. citratus. PMID:26904623

  16. Characteristics and transformations of dissolved organic nitrogen in municipal biological nitrogen removal wastewater treatment plants

    NASA Astrophysics Data System (ADS)

    Huo, Shouliang; Xi, Beidou; Yu, Honglei; Qin, Yanwen; Zan, Fengyu; Zhang, Jingtian

    2013-12-01

    Dissolved organic nitrogen (DON) represents most of the dissolved nitrogen in the effluent of biological nitrogen removal (BNR) wastewater treatment plants (WWTPs). The characteristics of wastewater-derived DON in two different WWTPs were investigated by several different methods. The major removals of DON and biodegradable dissolved organic nitrogen (BDON) along the treatment train were observed in the anaerobic process. Dissolved combined amino acids (DCAA) and dissolved free amino acids (DFAA) in the effluent accounted approximately for less than 4% and 1% of the effluent DON, respectively. Approximately half of wastewater-derived DON was capable of passing through a 1 kDa ultrafilter, and low MW DON cannot effectively be removed by BNR processes. More than 80% of effluent DON was composed of hydrophilic compounds, which stimulate algal growth. The study provided important information for future upgrading of WWTPs or the selection of DON removal systems to meet more demanding nitrogen discharge limits.

  17. HPLC-Profiles of Tocopherols, Sugars, and Organic Acids in Three Medicinal Plants Consumed as Infusions

    PubMed Central

    Roriz, Custódio Lobo; Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C. F. R.

    2014-01-01

    Pterospartum tridentatum (L.) Willk, Gomphrena globosa L., and Cymbopogon citratus (DC.) Stapf are medicinal plants that require a more detailed chemical characterization, given the importance of their consumption as infusions. Therefore, the individual profiles in tocopherols, free sugars, and organic acids were obtained by high performance liquid chromatography (HPLC) coupled to different detectors (fluorescence, refraction index, and photodiode array, resp.). C. citratus revealed the highest content of α-, and total tocopherols, glucose, sucrose, succinic, and ascorbic acids. P. tridentatum presented the highest fructose and total sugars content. Otherwise, G. globosa showed the highest organic acids concentration. As far as we know, this is the first study reporting the mentioned chemical compounds in G. globosa and C. citratus. PMID:26904623

  18. Recent Advances in the Application of Metabolomics to Studies of Biogenic Volatile Organic Compounds (BVOC) Produced by Plant

    PubMed Central

    Iijima, Yoko

    2014-01-01

    In many plants, biogenic volatile organic compounds (BVOCs) are produced as specialized metabolites that contribute to the characteristics of each plant. The varieties and composition of BVOCs are chemically diverse by plant species and the circumstances in which the plants grow, and also influenced by herbivory damage and pathogen infection. Plant-produced BVOCs are receptive to many organisms, from microorganisms to human, as both airborne attractants and repellants. In addition, it is known that some BVOCs act as signals to prime a plant for the defense response in plant-to-plant communications. The compositional profiles of BVOCs can, thus, have profound influences in the physiological and ecological aspects of living organisms. Apart from that, some of them are commercially valuable as aroma/flavor compounds for human. Metabolomic technologies have recently revealed new insights in biological systems through metabolic dynamics. Here, the recent advances in metabolomics technologies focusing on plant-produced BVOC analyses are overviewed. Their application markedly improves our knowledge of the role of BVOCs in chemosystematics, ecological influences, and aroma research, as well as being useful to prove the biosynthetic mechanisms of BVOCs. PMID:25257996

  19. Variable Contribution of Soil and Plant Derived Carbon to Dissolved Organic Matter

    NASA Astrophysics Data System (ADS)

    Steinbeiss, S.; Gleixner, G.

    2005-12-01

    The seasonal variation in the amount and sources of dissolved organic matter (DOM) in soil profiles was investigated. In general DOM in soil solution can evolve from the decomposition and mobilization of soil organic matter (SOM), dissolution of dead microbial cells or from the input of plant material such as root exudates or decomposing litter. Here we used vegetation change from C3 to C4 plants to quantify the plant derived carbon in DOM. In 2002 an agricultural field was converted to an experimental grass land. The average carbon isotope value of SOM was -26.5 per mill (sd = 0.2) for the plough horizon. On two independent plots, each 10 x 20 m, we used Amaranthus retroflexus as C4 plant with a carbon isotope label of 13.0 per mill to distinguish unlabeled SOM and plant derived carbon sources. To quantify the contribution of litter input on DOM formation we applied a split plot design. One half had no litter and the other half double amount of above ground litter. Soil water was collected in 10, 20 and 30 cm depth biweekly and DOM concentrations in solution and carbon isotope ratios of the freeze dried and decarbonized material were investigated. During winter uniform concentrations of DOM of about 7 mg/l were measured throughout all depth and treatments. In spring when soil temperatures increase and water availability decreases DOM concentrations increased with similar rates in all depth. Even in the second year of Amaranth growth the carbon isotope ratios of DOM in winter and spring had no C4 signal. The carbon isotope ratios of -26 to -27 per mill suggest SOM as carbon source and contradict a contribution of root exudates to the DOM pool. During summer almost no soil solution was collected. After rewetting in fall DOM concentrations up to 50 mg/l in 10 cm depth and up to 35 mg/l in deeper layers were found. These high concentrations held carbon isotope signals from -25 to -26.5 per mill contradicting carbon input from plant material. With ongoing wetting of

  20. Determination of low molecular weight organic acids in soil, plants, and water by capillary zone electrophoresis.

    PubMed

    Li, Ying-Hui; Huang, Bi-Xia; Shan, Xiao-Quan

    2003-03-01

    Determination of low molecular weight organic acids in soils and plants by capillary zone electrophoresis was accomplished using a phthalate buffer and indirect UV detection mode. The influence of some crucial parameters, such as pH, buffer concentration and surfactant were investigated. A good separation of seven organic acids was achieved within 5 min using an electrolyte containing 15 mmol L(-1) potassium hydrogen phthalate, 0.5 mmol L(-1) myristyltrimethylammonium bromide (MTAB), and 5% methanol (MeOH) (v/v) at pH 5.60, separation voltage -20 kV, and temperature 25 degrees C. The relative standard deviation (n=5) of the method was found to be in range 0.18-0.56% for migration time and 3.2-4.8% for peak area. The limit of detection ranged between 0.5 micro mol L(-1) to 6 micro mol L(-1) at a signal-to-noise ratio of 3. The recovery of standard organic acids added to real samples ranged from 87 to 119%. This method was simple, rapid and reproducible, and could be applied to the simultaneous determination of organic acids in environmental samples. PMID:12664177

  1. Experimental charcoalification of plant reproductive organs: Taphonomic implications for taxonomic information loss

    SciTech Connect

    Lupia, R. )

    1992-01-01

    Charcoalification can preserve reproductive organs of plants in exceptional detail, but it has not been clear to what extent these taxonomically important structures suffer non-allometric size reduction during this process. To address this problem, seven angiosperm and two gymnosperm species were buried in sand and experimentally charcoalified in a muffle furnace at 325--350 degrees Celsius for two hours, and percent size reduction measured. Carpels, stamens, and petals never shrank by the same amount for a given angiosperm species. To determine the effect of different periods of heating on organs, one angiosperm species was treated for 0.5, 1, 2, 4, and 6 hours. Organs continued to shrink over this entire period without reaching a plateau. This is important in designing future experiments, and in terms of interpreting fossils, since heat treatment varies across a single site in natural fires. Observations made during this study suggest that some carpels and petals never become charcoalified, that stamens are particularly susceptible to fragmentation after charcoalification, that some organs show predictable damage which is correlated with time, and that the saturation of a structure with water can significantly retard charcoalification for heat exposure of less than one hour. These factors may severely affect the entry of the charred remains into the fossil record. Despite the suggestion that female structures can be expected to shrink the least, it is impossible to prescribe quantitative correction factors to permit accurate reconstructions without constraining additional variables such as temperature and duration of heating.

  2. Organic matrix based slow release fertilizer enhances plant growth, nitrate assimilation and seed yield of Indian mustard (Brassica juncea L.).

    PubMed

    Sharma, Vinod K; Singh, Rana P

    2011-09-01

    Field experiments were conducted to study the effect of organic matrix based slow release fertilizers (SRFs) on plant growth, nitrate assimilation and seed yield of Brassica juncea L. cv, pusa bold. The agro-waste materials like cow dung, clay soil, neem leaves and rice bran were mixed together in 2:2:1:1 ratio and used as organic matrix for the immobilization of chemical fertilizer nutrients with commercial grade saresh (Acacia gum, 15% solution) as binder. Different fertilizer treatments were organic matrix based slow release fertilizers, SRF-I (542.0 kg ha(-1)); SRF-II (736.5 kg ha(-1)) and chemical fertilizer combinations, boron (3 kg ha(-1))+sulphur (15 kg ha(-1))+nitrogen (80 kg ha(-1)) and boron (3 kg ha(-1)) + sulphur (15 kg ha(-1))+nitrogen (80 kg ha(-1))+phosphorus (15 kg ha(-1))+potassium (100 kg ha(-1)). Organic matrix based SRF-II released ammonium up to 50-d in wetsoil under laboratory conditions which showed maximum retention of the nutrients. Avery significant increase in plant growth, nitrate assimilation and seed yield was recorded in organic matrix based SRF-II applied plants. The maximum percent increase in biomass production was observed with organic matrix based SRF-II (increase of 65.8% in root fresh weight, 38.0% in root dry weight, 45.9% in leaf fresh weight plant(-1) and 27.5 % in leaf dry weight plant(-1) in 60-d old plants). It also increased the acquisition and assimilation of nitrate from the plant's rhizosphere which was evident by 45.6% increase in nitrate, 27.5% in nitrite and 11.7% in nitrate reductase activity (NRA) in leaves of 45-d old plants over control. The organic matrix based SRF-II significantly increased the seed yield by 28% in Indian mustard. Cost analysis revealed thatthis formulation is cost effective as it is based on agro waste materials. PMID:22319878

  3. Plant inter-species effects on rhizosphere priming of soil organic matter decomposition

    NASA Astrophysics Data System (ADS)

    Pausch, Johanna; Zhu, Biao; Cheng, Weixin

    2015-04-01

    Living roots and their rhizodeposits can stimulate microbial activity and soil organic matter (SOM) decomposition up to several folds. This so-called rhizosphere priming effect (RPE) varies widely among plant species possibly due to species-specific differences in the quality and quantity of rhizodeposits and other root functions. However, whether the RPE is influenced by plant inter-species interactions remains largely unexplored, even though these interactions can fundamentally shape plant functions such as carbon allocation and nutrient uptake. In a 60-day greenhouse experiment, we continuously labeled monocultures and mixtures of sunflower, soybean and wheat with 13C-depleted CO2 and partitioned total CO2 efflux released from soil at two stages of plant development for SOM- and root-derived CO2. The RPE was calculated as the difference in SOM-derived CO2 between the planted and the unplanted soil, and was compared among the monocultures and mixtures. We found that the RPE was positive under all plants, ranging from 43% to 136% increase above the unplanted control. There were no significant differences in RPE at the vegetative stage. At the flowering stage however, the RPE in the soybean-wheat mixture was significantly higher than those in the sunflower monoculture, the sunflower-wheat mixture, and the sunflower-soybean mixture. These results indicated that the influence of plant inter-specific interactions on the RPE is case-specific and phenology-dependent. To evaluate the intensity of inter-specific effects on priming, we calculated an expected RPE for the mixtures based on the RPE of the monocultures weighted by their root biomass and compared it to the measured RPE under mixtures. At flowering, the measured RPE was significantly lower for the sunflower-wheat mixture than what can be expected from their monocultures, suggesting that RPE was significantly reduced by the inter-species effects of sunflower and wheat. In summary, our results clearly demonstrated

  4. Assessment of plant uptake models used in exposure assessment tools for soils contaminated with organic pollutants.

    PubMed

    Takaki, Koki; Wade, Andrew J; Collins, Chris D

    2014-10-21

    The aim of this study was to evaluate and improve the accuracy of plant uptake models for neutral hydrophobic organic pollutants (1 < logK(OW) < 9, -8 < logK(AW) < 0) used in regulatory exposure assessment tools, using uncertainty and sensitivity analyses. The models considered were RAIDAR, EUSES, CSOIL, CLEA, and CalTOX. In this research, CSOIL demonstrated the best performance of all five exposure assessment tools for root uptake from polluted soil in comparison with observed data, but no model predicted shoot uptake well. Recalibration of the transpiration and volatilisation parameters improved the performance of CSOIL and CLEA. The dominant pathway for shoot uptake simulated differed according to the properties of the chemical under consideration; those with a higher air-water partition coefficient were transported into shoots via the soil-air-plant pathway, while chemicals with a lower octanol-water partition coefficient and air-water partition coefficient were transported via the root. The soil organic carbon content was a particularly sensitive parameter in each model and using a site specific value improved model performance. PMID:25203369

  5. In vivo endocrine disruption assessment of wastewater treatment plant effluents with small organisms.

    PubMed

    Castillo, Luis; Seriki, Kemi; Mateos, Stéphanie; Loire, Nicolas; Guédon, Nathalie; Lemkine, Gregory F; Demeneix, Barbara A; Tindall, Andrew J

    2013-01-01

    Surface water receives a variety of micro-pollutants that could alter aquatic organisms' reproduction and development. It is known that a few nanograms per litre of these compounds can induce endocrine-disrupting effects in aquatic species. Many compounds are released daily in wastewater, and identifying the compounds responsible for inducing such disruption is difficult. Methods using biological analysis are therefore an alternative to chemical analysis, as the endocrine disruption potential of the stream as a whole is considered. To detect hormonal disruption of thyroid and oestrogenic functions, fluorescent Xenopus laevis tadpoles and medaka (Oryzias latipes) fish larvae bearing genetic constructs integrating hormonal responsive elements were used for physiological screens for potential endocrine disruption in streams from an urban wastewater treatment plant. The Xenopus model was used to assess thyroid disruption and the medaka model oestrogenic disruption in wastewater samples. Assays using the genetically modified organisms were conducted on 9 influent and 32 effluent samples. The thyroidal effect of wastewater was either reduced or removed by the treatment plant; no oestrogenic effect was detected in any of the wastewater samples. PMID:23823564

  6. Functions of tocopherols in the cells of plants and other photosynthetic organisms.

    PubMed

    Mokrosnop, V M

    2014-01-01

    Tocopherol synthesis has only been observed in photosynthetic organisms (plants, algae and some cyanobacteria). Tocopherol is synthesized in the inner membrane of chloroplasts and distributed between chloroplast membranes, thylakoids and plastoglobules. Physiological significance of tocopherols for human and animal is well-studied, but relatively little is known about their function in plant organisms. Among the best characterized functions oftocopherols in cells is their ability to scavenge and quench reactive oxygen species and fat-soluble by-products of oxidative stress. There are the data on the participation of different mechanisms of α-tocopherol action in protecting photosystem II (PS II) from photoinhibition both by deactivation of singlet oxygen produced by PSII and by reduction of proton permeability of thylakoid membranes, leading to acidification of lumen under high light conditions and activation of violaxanthin de-epoxidase. Additional biological activity of tocopherols, independent of its antioxidant functions have been demonstrated. Basic mechanisms for these effects are connected with the modulation of signal transduction pathways by specific tocopherols and, in some instances, by transcriptional activation of gene expression. PMID:25816585

  7. Refuse derived soluble bio-organics enhancing tomato plant growth and productivity.

    PubMed

    Sortino, Orazio; Dipasquale, Mauro; Montoneri, Enzo; Tomasso, Lorenzo; Perrone, Daniele G; Vindrola, Daniela; Negre, Michele; Piccone, Giuseppe

    2012-10-01

    Municipal bio-refuse (CVD), containing kitchen wastes, home gardening residues and public park trimmings, was treated with alkali to yield a soluble bio-organic fraction (SBO) and an insoluble residue. These materials were characterized using elemental analysis, potentiometric titration, and 13C NMR spectroscopy, and then applied as organic fertilizers to soil for tomato greenhouse cultivation. Their performance was compared with a commercial product obtained from animal residues. Plant growth, fruit yield and quality, and soil and leaf chemical composition were the selected performance indicators. The SBO exhibited the best performance by enhancing leaf chlorophyll content, improving plant growth and fruit ripening rate and yield. No product performance-chemical composition relationship could be assessed. Solubility could be one reason for the superior performance of SBO as a tomato growth promoter. The enhancement of leaf chlorophyll content is discussed to identify a possible link with the SBO photosensitizing properties that have been demonstrated in other work, and thus with photosynthetic performance. PMID:22658869

  8. A Survey Report of School Plant Management for Escambia County, Florida.

    ERIC Educational Resources Information Center

    Florida State Dept. of Education, Tallahassee.

    This report analyzes data collected by survey teams concerned with maintenance and operation of school plants in relation to organization, administration, budgeting, expenditures, purchasing, staffing, warehousing and distribution, maintenance shops, administrative practices, performance standards, and efficiency. The basic purposes of a…

  9. Impact of liquid fertilizers on plant growth, yield, fruit quality and fertigation management in an organic processing blackberry production system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact of organic fertilizer source on the growth, fruit quality, and yield of blackberry cultivars (‘Marion’ and ‘Black Diamond’) grown in machine-harvested, organic production systems for the processed market was evaluated from 2011-13. The planting was established in spring 2010 using approve...

  10. Plant-specific volatile organic compound emission rates from young and mature leaves of Mediterranean vegetation

    NASA Astrophysics Data System (ADS)

    Bracho-Nunez, Araceli; Welter, Saskia; Staudt, Michael; Kesselmeier, Jürgen

    2011-08-01

    The seasonality of vegetation, i.e., developmental stages and phenological processes, affects the emission of volatile organic compounds (VOCs). Despite the potential significance, the contributions of seasonality to VOC emission quality and quantity are not well understood and are therefore often ignored in emission simulations. We investigated the VOC emission patterns of young and mature leaves of several Mediterranean plant species in relation to their physiological and developmental changes during the growing period and estimated Es. Foliar emissions of isoprenoids and oxygenated VOCs like methanol and acetone were measured online by means of a proton transfer reaction mass spectrometer (PTR-MS) and offline with gas chromatography coupled with a mass spectrometer and flame ionization detector. The results suggest that VOC emission is a developmentally regulated process and that quantitative and qualitative variability is plant species specific. Leaf ontogeny clearly influenced both the VOC Es and the relative importance of different VOCs. Methanol was the major compound contributing to the sum of target VOC emissions in young leaves (11.8 ± 10.4 μg g-1 h-1), while its contribution was minor in mature leaves (4.1 ± 4.1 μg g-1 h-1). Several plant species showed a decrease or complete subsidence of monoterpene, sesquiterpene, and acetone emissions upon maturity, perhaps indicating a potential response to the higher defense demands of young emerging leaves.

  11. Impacts of simulated herbivory on volatile organic compound emission profiles from coniferous plants

    DOE PAGESBeta

    Faiola, C. L.; Jobson, B. T.; VanReken, T. M.

    2015-01-28

    The largest global source of volatile organic compounds (VOCs) in the atmosphere is from biogenic emissions. Plant stressors associated with a changing environment can alter both the quantity and composition of the compounds that are emitted. This study investigated the effects of one global change stressor, increased herbivory, on plant emissions from five different coniferous species: bristlecone pine (Pinus aristata), blue spruce (Picea pungens), western redcedar (Thuja plicata), grand fir (Abies grandis), and Douglas-fir (Pseudotsuga menziesii). Herbivory was simulated in the laboratory via exogenous application of methyl jasmonate (MeJA), a herbivory proxy. Gas-phase species were measured continuously with a gasmore » chromatograph coupled to a mass spectrometer and flame ionization detector (GC–MS–FID). Stress responses varied between the different plant types and even between experiments using the same set of saplings. The compounds most frequently impacted by the stress treatment were alpha-pinene, beta-pinene, 1,8-cineol, beta-myrcene, terpinolene, limonene, and the cymene isomers. Individual compounds within a single experiment often exhibited a different response to the treatment from one another.« less

  12. Light represses transcription of asparagine synthetase genes in photosynthetic and nonphotosynthetic organs of plants

    SciTech Connect

    Tsai, Fongying; Coruzzi, G. )

    1991-10-01

    Asparagine synthetase (AS) mRNA in Pisum sativum accumulates preferentially in plants grown in the dark. Nuclear run-on experiments demonstrate that expression of both the AS1 and AS2 genes is negatively regulated by light at the level of transcription. A decrease in the transcriptional rate of the AS1 gene can be detected as early as 20 min after exposure to light. Time course experiments reveal that the levels of AS mRNA fluctuate dramatically during a normal light/dark cycle. This is due to a direct effect of light and not to changes associated with circadian rhythm. A novel finding is that the light-repressed expression of the AS1 gene is as dramatic nonphotosynthetic organs such as roots as it is in leaves. Experiments demonstrate that the small amount of light which passes through the soil is sufficient to repress AS1 expression in roots, indicating that light has a direct effect on AS1 gene expression in roots. The negative regulation of AS gene expression by light was shown to be a general phenomenon in plants which also occurs in nonlegumes such as Nicotiana plumbaginifolia and Nicotiana tabacum. Thus, the AS genes can serve as a model with which to dissect the molecular basis for light-regulated transcriptional repression in plants.

  13. Impacts of simulated herbivory on volatile organic compound emission profiles from coniferous plants

    NASA Astrophysics Data System (ADS)

    Faiola, C. L.; Jobson, B. T.; VanReken, T. M.

    2015-01-01

    The largest global source of volatile organic compounds (VOCs) in the atmosphere is from biogenic emissions. Plant stressors associated with a changing environment can alter both the quantity and composition of the compounds that are emitted. This study investigated the effects of one global change stressor, increased herbivory, on plant emissions from five different coniferous species: bristlecone pine (Pinus aristata), blue spruce (Picea pungens), western redcedar (Thuja plicata), grand fir (Abies grandis), and Douglas-fir (Pseudotsuga menziesii). Herbivory was simulated in the laboratory via exogenous application of methyl jasmonate (MeJA), a herbivory proxy. Gas-phase species were measured continuously with a gas chromatograph coupled to a mass spectrometer and flame ionization detector (GC-MS-FID). Stress responses varied between the different plant types and even between experiments using the same set of saplings. The compounds most frequently impacted by the stress treatment were alpha-pinene, beta-pinene, 1,8-cineol, beta-myrcene, terpinolene, limonene, and the cymene isomers. Individual compounds within a single experiment often exhibited a different response to the treatment from one another.

  14. Mechanisms of Heavy Metal Sequestration in Soils: Plant-Microbe Interactions and Organic Matter Aging

    SciTech Connect

    Fan, Teresa W.-M; Higashi, Richard M.

    2001-06-01

    The myriad of human activities including strategic and energy development at various DOE installations have resulted in the contamination of soils and waterways that can seriously threaten human and ecosystem health. Development of efficacious and economical remediation technologies is needed to ameliorate these immensely costly problems. Bioremediation (both plant and microbe-based) has promising potential to meet this demand but still requires advances in fundamental knowledge. For bioremediation of heavy metals, the three-way interaction of plant root, microbial community, and soil organic matter (SOM)1 in the rhizosphere is critically important for long-term sustainability but often underconsidered. Particularly urgent is the need to understand processes that lead to metal ion stabilization in soils, which is crucial to all of the goals of bioremediation: removal, stabilization, and transformation. This project will build on the knowledge that we have generated on the role of root exudation and metabolism for metal mobilization and accumulation, to address the following objectives: (1) Identify molecular markers and characterize the chemical nature of recalcitrant SOM pools that are involved in belowground metal ion interactions, which are likely to be markers for sustainable sequestration; (2) Utilize (1) to determine plant and microbial factors that contribute to sustainable metal sequestration or mobility, as well as bioavailability; (3) Utilize information from (1) and (2) to explore efficacious means for enhancing sustainable phytostabilization of heavy metals in the subsurface zone.

  15. Mechanisms of Heavy Metal Sequestration in Soils: Plant-Microbe Interactions and Organic Matter Aging

    SciTech Connect

    Fan, Teresa W. M.; Higashi, Richard M.; Crowley

    2001-06-25

    The myriad of human activities including strategic and energy development at various DOE installations have resulted in the contamination of soils and waterways that can seriously threaten human and ecosystem health. Development of efficacious and economical remediation technologies is needed to ameliorate these immensely costly problems. Bioremediation (both plant and microbe-based) has promising potential to meet this demand but still requires advances in fundamental knowledge. For bioremediation of heavy metals, the three-way interaction of plant root, microbial community, and soil organic matter (SOM)1 in the rhizosphere is critically important for long-term sustainability but often underconsidered. Particularly urgent is the need to understand processes that lead to metal ion stabilization in soils, which is crucial to all of the goals of bioremediation: removal, stabilization, and transformation. This project will build on the knowledge that we have generated on the role of root exudation and metabolism for metal mobilization and accumulation, to address the following objectives: (1) Identify molecular markers and characterize the chemical nature of recalcitrant SOM pools that are involved in below ground metal ion interactions, which are likely to be markers for sustainable sequestration; (2) Utilize (1) to determine plant and microbial factors that contribute to sustainable metal sequestration or mobility, as well as bioavailability; (3) Utilize information from (1) and (2) to explore efficacious means for enhancing sustainable phytostabilization of heavy metals in the subsurface zone.

  16. Roles of Organic Acid Anion Secretion in Aluminium Tolerance of Higher Plants

    PubMed Central

    Yang, Lin-Tong; Qi, Yi-Ping; Jiang, Huan-Xin; Chen, Li-Song

    2013-01-01

    Approximately 30% of the world's total land area and over 50% of the world's potential arable lands are acidic. Furthermore, the acidity of the soils is gradually increasing as a result of the environmental problems including some farming practices and acid rain. At mildly acidic or neutral soils, aluminium(Al) occurs primarily as insoluble deposits and is essentially biologically inactive. However, in many acidic soils throughout the tropics and subtropics, Al toxicity is a major factor limiting crop productivity. The Al-induced secretion of organic acid (OA) anions, mainly citrate, oxalate, and malate, from roots is the best documented mechanism of Al tolerance in higher plants. Increasing evidence shows that the Al-induced secretion of OA anions may be related to the following several factors, including (a) anion channels or transporters, (b) internal concentrations of OA anions in plant tissues, (d) temperature, (e) root plasma membrane (PM) H+-ATPase, (f) magnesium (Mg), and (e) phosphorus (P). Genetically modified plants and cells with higher Al tolerance by overexpressing genes for the secretion and the biosynthesis of OA anions have been obtained. In addition, some aspects needed to be further studied are also discussed. PMID:23509687

  17. Assessment of volatile organic compound removal by indoor plants--a novel experimental setup.

    PubMed

    Dela Cruz, Majbrit; Müller, Renate; Svensmark, Bo; Pedersen, Jakob Skov; Christensen, Jan H

    2014-01-01

    Indoor plants can remove volatile organic compounds (VOCs) from the air. The majority of knowledge comes from laboratory studies where results cannot directly be transferred to real-life settings. The aim of this study was to develop an experimental test system to assess VOC removal by indoor plants which allows for an improved real-life simulation. Parameters such as relative humidity, air exchange rate and VOC concentration are controlled and can be varied to simulate different real-life settings. For example, toluene diffusion through a needle gave concentrations in the range of 0.10-2.35 μg/L with deviations from theoretical values of 3.2-10.5%. Overall, the system proved to be functional for the assessment of VOC removal by indoor plants with Hedera helix reaching a toluene removal rate of up to 66.5 μg/m(2)/h. The mode of toluene exposure (semi-dynamic or dynamic) had a significant influence on the removal rate obtained by H. helix. PMID:24638833

  18. Roles of organic acid anion secretion in aluminium tolerance of higher plants.

    PubMed

    Yang, Lin-Tong; Qi, Yi-Ping; Jiang, Huan-Xin; Chen, Li-Song

    2013-01-01

    Approximately 30% of the world's total land area and over 50% of the world's potential arable lands are acidic. Furthermore, the acidity of the soils is gradually increasing as a result of the environmental problems including some farming practices and acid rain. At mildly acidic or neutral soils, aluminium (Al) occurs primarily as insoluble deposits and is essentially biologically inactive. However, in many acidic soils throughout the tropics and subtropics, Al toxicity is a major factor limiting crop productivity. The Al-induced secretion of organic acid (OA) anions, mainly citrate, oxalate, and malate, from roots is the best documented mechanism of Al tolerance in higher plants. Increasing evidence shows that the Al-induced secretion of OA anions may be related to the following several factors, including (a) anion channels or transporters, (b) internal concentrations of OA anions in plant tissues, (d) temperature, (e) root plasma membrane (PM) H(+)-ATPase, (f) magnesium (Mg), and (e) phosphorus (P). Genetically modified plants and cells with higher Al tolerance by overexpressing genes for the secretion and the biosynthesis of OA anions have been obtained. In addition, some aspects needed to be further studied are also discussed. PMID:23509687

  19. Plant specific volatile organic compound emission factors from young and mature leaves of Mediterranean vegetation

    NASA Astrophysics Data System (ADS)

    Bracho-Nunez, Araceli; Welter, Saskia; Staudt, Michael; Kesselmeier, Jürgen

    2010-05-01

    Terrestrial vegetation is the most important source of atmospheric volatile organic compounds (VOC) with significant influence on the chemistry and physics of the atmosphere. VOCs influence the oxidative capacity of the atmosphere and contribute to the formation and growth of secondary organic aerosols affecting cloud development and precipitation. The aim of our study was to investigate potential quantitative and qualitative differences in VOC emission patterns of young and mature leaves for nine typical Mediterranean plant species. The Mediterranean area was chosen due to its special diversity in VOC emitting plant species. Foliar isoprenoid emissions as well as emissions of oxygenated VOC like methanol and acetone were measured under standard light and temperature conditions during spring and summer 2008 at the CEFE-CNRS institute in Montpellier, France. A proton transfer reaction mass spectrometer (PTR-MS) was used for online measurement of VOCs. While PTR-MS is an excellent technique for fast chemical measurements it lacks specificity and compounds with the same mass cannot be distinguished. For this reason, cartridge samples were collected and afterwards analyzed with GC-FID. In parallel offline VOC analyses were performed with gas chromatography (GC) coupled to a mass spectrometer and flame ionization detector, enabling assignment of the observed PTR-MS mass to charge ratios (m/z) to specific identification based on the GC-FID retention times. Thus, combining the PTR-MS and GC-FID analyses enabled accurate and online identification of the VOCs emitted. The results emphasise that VOC emission is a developmentally regulated process and quantitative and qualitative variability is plant species specific. Leaf ontogeny clearly influenced not only the standard emission rate but also the VOC composition, with methanol being the major compound that contributes to the total VOC emissions in young leaves and maintaining or decreasing its contribution with maturity.

  20. Conventional and organic soil fertility management practices affect corn plant nutrition and Ostrinia nubilalis (Lepidoptera: Crambidae) larval performance.

    PubMed

    Murrell, Ebony G; Cullen, Eileen M

    2014-10-01

    Few studies compare how different soil fertilization practices affect plant mineral content and insect performance in organic systems. This study examined: 1) The European corn borer, Ostrinia nubilalis (Hübner), larval response on corn (Zea mays L.) grown in field soils with different soil management histories; and 2) resilience of these plants to O. nubilalis herbivory. Treatments included: 1) standard organic--organically managed soil fertilized with dairy manure and 2 yr of alfalfa (Medicago sativa L.) in the rotation; 2) basic cation saturation ratio--organically managed soil fertilized with dairy manure and alfalfa nitrogen credits, plus addition of gypsum (CaSO4·2H2O) according to the soil balance hypothesis; and 3) conventional--conventionally managed soil fertilized with synthetic fertilizers. Corn plants were reared to maturity in a greenhouse, and then infested with 0-40 O. nubilalis larvae for 17 d. O. nubilalis exhibited negative competitive response to increasing larval densities. Mean development time was significantly faster for larvae consuming basic cation saturation ratio plants than those on standard organic plants, with intermediate development time on conventional plants. Neither total yield (number of kernels) nor proportion kernels damaged differed among soil fertility treatments. Soil nutrients differed significantly in S and in Ca:Mg and Ca:K ratios, but principal components analysis of plant tissue samples taken before O. nubilalis infestation showed that S, Fe, and Cu contributed most to differences in plant nutrient profiles among soil fertility treatments. Results demonstrate that different fertilization regimens can significantly affect insect performance within the context of organic systems, but the effects in this study were relatively minor compared with effects of intraspecific competition. PMID:25203485

  1. Applications of Fluorescence Spectroscopy for dissolved organic matter characterization in wastewater treatment plants

    NASA Astrophysics Data System (ADS)

    Goffin, Angélique; Guérin, Sabrina; Rocher, Vincent; Varrault, Gilles

    2016-04-01

    Dissolved organic matter (DOM) influences wastewater treatment plants efficiency (WTTP): variations in its quality and quantity can induce a foaming phenomenon and a fouling event inside biofiltration processes. Moreover, in order to manage denitrification step (control and optimization of the nitrate recirculation), it is important to be able to estimate biodegradable organic matter quantity before biological treatment. But the current methods used to characterize organic matter quality, like biological oxygen demand are laborious, time consuming and sometimes not applicable to directly monitor organic matter in situ. In the context of MOCOPEE research program (www.mocopee.com), this study aims to assess the use of optical techniques, such as UV-Visible absorbance and more specifically fluorescence spectroscopy in order to monitor and to optimize process efficiency in WWTP. Fluorescence excitation-emission matrix (EEM) spectroscopy was employed to prospect the possibility of using this technology online and in real time to characterize dissolved organic matter in different effluents of the WWTP Seine Centre (240,000 m3/day) in Paris, France. 35 sewage water influent samples were collected on 10 days at different hours. Data treatment were performed by two methods: peak picking and parallel factor analysis (PARAFAC). An evolution of DOM quality (position of excitation - emission peaks) and quantity (intensity of fluorescence) was observed between the different treatment steps (influent, primary treatment, biological treatment, effluent). Correlations were found between fluorescence indicators and different water quality key parameters in the sewage influents. We developed different multivariate linear regression models in order to predict a variety of water quality parameters by fluorescence intensity at specific excitation-emission wavelengths. For example dissolved biological oxygen demand (r2=0,900; p<0,0001) and ammonium concentration (r2=0,898; p<0

  2. The Organization of Controller Motifs Leading to Robust Plant Iron Homeostasis

    PubMed Central

    Agafonov, Oleg; Selstø, Christina Helen; Thorsen, Kristian; Xu, Xiang Ming; Drengstig, Tormod; Ruoff, Peter

    2016-01-01

    Iron is an essential element needed by all organisms for growth and development. Because iron becomes toxic at higher concentrations iron is under homeostatic control. Plants face also the problem that iron in the soil is tightly bound to oxygen and difficult to access. Plants have therefore developed special mechanisms for iron uptake and regulation. During the last years key components of plant iron regulation have been identified. How these components integrate and maintain robust iron homeostasis is presently not well understood. Here we use a computational approach to identify mechanisms for robust iron homeostasis in non-graminaceous plants. In comparison with experimental results certain control arrangements can be eliminated, among them that iron homeostasis is solely based on an iron-dependent degradation of the transporter IRT1. Recent IRT1 overexpression experiments suggested that IRT1-degradation is iron-independent. This suggestion appears to be misleading. We show that iron signaling pathways under IRT1 overexpression conditions become saturated, leading to a breakdown in iron regulation and to the observed iron-independent degradation of IRT1. A model, which complies with experimental data places the regulation of cytosolic iron at the transcript level of the transcription factor FIT. Including the experimental observation that FIT induces inhibition of IRT1 turnover we found a significant improvement in the system’s response time, suggesting a functional role for the FIT-mediated inhibition of IRT1 degradation. By combining iron uptake with storage and remobilization mechanisms a model is obtained which in a concerted manner integrates iron uptake, storage and remobilization. In agreement with experiments the model does not store iron during its high-affinity uptake. As an iron biofortification approach we discuss the possibility how iron can be accumulated even during high-affinity uptake. PMID:26800438

  3. Influence of atmospheric [CO2] on growth, carbon allocation and cost of plant tissues on leaf nitrogen concentration maintenance in nodulated Medicago sativa

    NASA Astrophysics Data System (ADS)

    Pereyra, Gabriela; Hartmann, Henrik; Ziegler, Waldemar; Michalzik, Beate; Gonzalez-Meler, Miquel; Trumbore, Susan

    2015-04-01

    Plant carbon (C) allocation and plant metabolic processes (i.e. photosynthesis and respiration) can be affected by changes in C availability, for example from changing atmospheric [CO2]. In nodulated plants, C availability may also influence nitrogen (N) fixation by bacteriods. But C allocation and N fixation are often studied independently and hence do not allow elucidating interactive effects. We investigated how different atmospheric [CO2] (Pleistocene: 170 ppm, ambient: 400 ppm and projected future: 700 ppm) influence plant growth, allocation to nodules, and the ratio of photosynthesis-to-respiration (R:A) as an indicator of C cost in Medicago sativa inoculated with Ensifer meliloti. M. sativa grew c. 38% more nodules at 400 ppm and 700 ppm than at 170 ppm. However, ratios of above- and belowground plant biomass to nodule biomass were constant over time and independent of atmospheric [CO2]. Total non-structural carbohydrate concentrations were not significantly different between plants grown at 400 and 700 ppm, but were four to five-fold higher than in 170 ppm plants. Leaf level N concentration was similar across treatments, but N-based photosynthetic rates were 82% and 93% higher in leaves of plants grown at 400 and 700 ppm, respectively, than plants grown at 170 ppm. In addition, leaf R:A was greater (48% or 55%) in plants grown at 170 ppm than plants grown at 400 and 700 ppm. Similarly, the greatest proportion of assimilated CO2 released by root respiration occurred in rhizobial plants growing at 170 ppm. Our results suggest that C limitation in nodulated Medicago sativa plants did not influence C allocation to nodule biomass but caused a proportionally greater allocation of C to belowground respiration, most likely to bacteriods. This suggests that N tissue concentration was maintained at low [CO2] by revving up bacteriod metabolism and at the expense of non-structural carbohydrate reserves.

  4. Transcriptional repression by MYB3R proteins regulates plant organ growth

    PubMed Central

    Kobayashi, Kosuke; Suzuki, Toshiya; Iwata, Eriko; Nakamichi, Norihito; Suzuki, Takamasa; Chen, Poyu; Ohtani, Misato; Ishida, Takashi; Hosoya, Hanako; Müller, Sabine; Leviczky, Tünde; Pettkó-Szandtner, Aladár; Darula, Zsuzsanna; Iwamoto, Akitoshi; Nomoto, Mika; Tada, Yasuomi; Higashiyama, Tetsuya; Demura, Taku; Doonan, John H; Hauser, Marie-Theres; Sugimoto, Keiko; Umeda, Masaaki; Magyar, Zoltán; Bögre, László; Ito, Masaki

    2015-01-01

    In multicellular organisms, temporal and spatial regulation of cell proliferation is central for generating organs with defined sizes and morphologies. For establishing and maintaining the post-mitotic quiescent state during cell differentiation, it is important to repress genes with mitotic functions. We found that three of the Arabidopsis MYB3R transcription factors synergistically maintain G2/M-specific genes repressed in post-mitotic cells and restrict the time window of mitotic gene expression in proliferating cells. The combined mutants of the three repressor-type MYB3R genes displayed long roots, enlarged leaves, embryos, and seeds. Genome-wide chromatin immunoprecipitation revealed that MYB3R3 binds to the promoters of G2/M-specific genes and to E2F target genes. MYB3R3 associates with the repressor-type E2F, E2FC, and the RETINOBLASTOMA RELATED proteins. In contrast, the activator MYB3R4 was in complex with E2FB in proliferating cells. With mass spectrometry and pairwise interaction assays, we identified some of the other conserved components of the multiprotein complexes, known as DREAM/dREAM in human and flies. In plants, these repressor complexes are important for periodic expression during cell cycle and to establish a post-mitotic quiescent state determining organ size. PMID:26069325

  5. Colloidal organic matter from wastewater treatment plant effluents: Characterization and role in metal distribution.

    PubMed

    Worms, Isabelle A M; Al-Gorani Szigeti, Zsofia; Dubascoux, Stephane; Lespes, Gaetane; Traber, Jacqueline; Sigg, Laura; Slaveykova, Vera I

    2010-01-01

    Colloidal organic matter from wastewater treatment plants was characterized and examined with respect to its role in metal distribution by using tangential flow ultrafiltration, liquid chromatography coupled with organic carbon and UV detectors, and an asymmetrical flow field-flow fractionation (AFlFFF) multidetection platform. Results revealed that a humic-like fraction of low aromaticity with an average molar mass ranging from 1600 to 2600Da was the main colloidal component. High molar mass fractions (HMM), with molar mass ranges between 20 and 200kDa, were present in lower proportions. Ag, Cd, Cu, Cr, Mn and Zn were found mainly in the dissolved phase (<0.45microm) and their distribution between colloidal and truly dissolved fractions was strongly influenced by the distribution of dissolved organic carbon. AFlFFF coupled to ICP-MS showed that Ag, Cd, Cu, Cr, Mn and Zn associate to the low molar mass fraction of the colloidal pool, whereas Al, Fe and Pb were equally bound to low and high molar mass fractions. PMID:19836819

  6. Effects of Water Stress on the Organic Acid and Carbohydrate Compositions of Cotton Plants

    PubMed Central

    Timpa, Judy D.; Burke, John J.; Quisenberry, Jerry E.; Wendt, Charles W.

    1986-01-01

    Two photoperiodic cotton (Gossypium hirsutum L.) strains (T185 and T466) which had been empirically selected because of poor performance and two strains (T25 and T256) selected because of enhanced performance under field water stress were evaluated for stress-induced changes in their organic acids and carbohydrates. Profiles and quantitation of organic acids and carbohydrates from aqueous extractions of cotton leaf tissue were determined by high performance liquid chromatography. In all cases, the water-stressed plants showed two to five times greater amounts of organic acids and carbohydrates over the values determined for the irrigated samples. Under stress, sucrose accumulation was observed in wilting strains (poor performers) probably related to rate of translocation out of the leaf. The most dramatic response to water stress was the accumulation of citric acid in strains T25 and T256 as compared to T185 and T466. Citric/malic acid ratios for both the irrigated and water-stressed samples of T25 and T256 were twice those of T185 and T466. PMID:16665100

  7. Air monitoring for volatile organic compounds at the Pilot Plant Complex, Aberdeen Proving Ground, Maryland

    SciTech Connect

    Schneider, J.F.; O`Neill, H.J.; Raphaelian, L.A.; Tomczyk, N.A.; Sytsma, L.F.; Cohut, V.J.; Cobo, H.A.; O`Reilly, D.P.; Zimmerman, R.E.

    1995-03-01

    The US Army`s Aberdeen Proving Ground has been a test site for a variety of munitions, including chemical warfare agents (CWA). The Pilot Plant Complex (PPC) at Aberdeen was the site of development, manufacture, storage, and disposal of CWA. Deterioration of the buildings and violations of environmental laws led to closure of the complex in 1986. Since that time, all equipment, piping, and conduit in the buildings have been removed. The buildings have been declared free of surface CWA contamination as a result of air sampling using the military system. However, no air sampling has been done to determine if other hazardous volatile organic compounds are present in the PPC, although a wide range of toxic and/or hazardous materials other than CWA was used in the PPC. The assumption has been that the air in the PPC is not hazardous. The purpose of this air-monitoring study was to screen the indoor air in the PPC to confirm the assumption that the air does not contain volatile organic contaminants at levels that would endanger persons in the buildings. A secondary purpose was to identify any potential sources of volatile organic contaminants that need to be monitored in subsequent sampling efforts.

  8. Vertex-element models for anisotropic growth of elongated plant organs

    PubMed Central

    Fozard, John A.; Lucas, Mikaël; King, John R.; Jensen, Oliver E.

    2013-01-01

    New tools are required to address the challenge of relating plant hormone levels, hormone responses, wall biochemistry and wall mechanical properties to organ-scale growth. Current vertex-based models (applied in other contexts) can be unsuitable for simulating the growth of elongated organs such as roots because of the large aspect ratio of the cells, and these models fail to capture the mechanical properties of cell walls in sufficient detail. We describe a vertex-element model which resolves individual cells and includes anisotropic non-linear viscoelastic mechanical properties of cell walls and cell division whilst still being computationally efficient. We show that detailed consideration of the cell walls in the plane of a 2D simulation is necessary when cells have large aspect ratio, such as those in the root elongation zone of Arabidopsis thaliana, in order to avoid anomalous transverse swelling. We explore how differences in the mechanical properties of cells across an organ can result in bending and how cellulose microfibril orientation affects macroscale growth. We also demonstrate that the model can be used to simulate growth on realistic geometries, for example that of the primary root apex, using moderate computational resources. The model shows how macroscopic root shape can be sensitive to fine-scale cellular geometries. PMID:23847638

  9. Crew interface specifications development for inflight maintenance and stowage functions

    NASA Technical Reports Server (NTRS)

    Carl, J. G.

    1974-01-01

    Findings and data products developed during crew specification study for inflight maintenance and stowage functions are reported. From this information base, a family of data concepts to support crew inflight troubleshooting and corrective maintenance activities was developed and specified. Recommendations are made for the improvement of inflight maintenance planning, preparations and operations in future space flight programs through the establishment of an inflight maintenance organization and specific suggestions for techniques to improve the management of the inflight maintenance function.

  10. Laboratory Maintenance of Acinetobacter baumannii.

    PubMed

    Jacobs, Anna C; Zurawski, Daniel V

    2014-01-01

    Acinetobacter baumannii has recently drawn great interest in the microbiology research community due to the increase in clinical antibiotic resistance of this organism, and persistence of this bacterial species in the hospital environment. This unit outlines protocols for the growth and maintenance of A. baumannii in the laboratory. PMID:25367273

  11. Influence of Seeding Ratio, Planting Date, and Termination Date on Rye-Hairy Vetch Cover Crop Mixture Performance under Organic Management

    PubMed Central

    Lawson, Andrew; Cogger, Craig; Bary, Andy; Fortuna, Ann-Marie

    2015-01-01

    Cover crop benefits include nitrogen accumulation and retention, weed suppression, organic matter maintenance, and reduced erosion. Organic farmers need region-specific information on winter cover crop performance to effectively integrate cover crops into their crop rotations. Our research objective was to compare cover crop seeding mixtures, planting dates, and termination dates on performance of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) monocultures and mixtures in the maritime Pacific Northwest USA. The study included four seed mixtures (100% hairy vetch, 25% rye-75% hairy vetch, 50% rye-50% hairy vetch, and 100% rye by seed weight), two planting dates, and two termination dates, using a split-split plot design with four replications over six years. Measurements included winter ground cover; stand composition; cover crop biomass, N concentration, and N uptake; and June soil NO3--N. Rye planted in mid-September and terminated in late April averaged 5.1 Mg ha-1 biomass, whereas mixtures averaged 4.1 Mg ha-1 and hairy vetch 2.3 Mg ha-1. Delaying planting by 2.5 weeks reduced average winter ground cover by 65%, biomass by 50%, and cover crop N accumulation by 40%. Similar reductions in biomass and N accumulation occurred for late March termination, compared with late April termination. Mixtures had less annual biomass variability than rye. Mixtures accumulated 103 kg ha-1 N and had mean C:N ratio <17:1 when planted in mid-September and terminated in late April. June soil NO3--N (0 to 30 cm depth) averaged 62 kg ha-1 for rye, 97 kg ha-1 for the mixtures, and 119 kg ha-1 for hairy vetch. Weeds comprised less of the mixtures biomass (20% weeds by weight at termination) compared with the monocultures (29%). Cover crop mixtures provided a balance between biomass accumulation and N concentration, more consistent biomass over the six-year study, and were more effective at reducing winter weeds compared with monocultures. PMID:26080008

  12. Influence of Seeding Ratio, Planting Date, and Termination Date on Rye-Hairy Vetch Cover Crop Mixture Performance under Organic Management.

    PubMed

    Lawson, Andrew; Cogger, Craig; Bary, Andy; Fortuna, Ann-Marie

    2015-01-01

    Cover crop benefits include nitrogen accumulation and retention, weed suppression, organic matter maintenance, and reduced erosion. Organic farmers need region-specific information on winter cover crop performance to effectively integrate cover crops into their crop rotations. Our research objective was to compare cover crop seeding mixtures, planting dates, and termination dates on performance of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) monocultures and mixtures in the maritime Pacific Northwest USA. The study included four seed mixtures (100% hairy vetch, 25% rye-75% hairy vetch, 50% rye-50% hairy vetch, and 100% rye by seed weight), two planting dates, and two termination dates, using a split-split plot design with four replications over six years. Measurements included winter ground cover; stand composition; cover crop biomass, N concentration, and N uptake; and June soil NO3(-)-N. Rye planted in mid-September and terminated in late April averaged 5.1 Mg ha(-1) biomass, whereas mixtures averaged 4.1 Mg ha(-1) and hairy vetch 2.3 Mg ha(-1). Delaying planting by 2.5 weeks reduced average winter ground cover by 65%, biomass by 50%, and cover crop N accumulation by 40%. Similar reductions in biomass and N accumulation occurred for late March termination, compared with late April termination. Mixtures had less annual biomass variability than rye. Mixtures accumulated 103 kg ha(-1) N and had mean C:N ratio <17:1 when planted in mid-September and terminated in late April. June soil NO3(-)-N (0 to 30 cm depth) averaged 62 kg ha(-1) for rye, 97 kg ha(-1) for the mixtures, and 119 kg ha(-1) for hairy vetch. Weeds comprised less of the mixtures biomass (20% weeds by weight at termination) compared with the monocultures (29%). Cover crop mixtures provided a balance between biomass accumulation and N concentration, more consistent biomass over the six-year study, and were more effective at reducing winter weeds compared with monocultures. PMID:26080008

  13. From genes to ecosystems: a synthesis of the effects of plant genetic factors across levels of organization

    PubMed Central

    Bailey, Joseph K.; Schweitzer, Jennifer A.; Úbeda, Francisco; Koricheva, Julia; LeRoy, Carri J.; Madritch, Michael D.; Rehill, Brian J.; Bangert, Randy K.; Fischer, Dylan G.; Allan, Gerard J.; Whitham, Thomas G.

    2009-01-01

    Using two genetic approaches and seven different plant systems, we present findings from a meta-analysis examining the strength of the effects of plant genetic introgression and genotypic diversity across individual, community and ecosystem levels with the goal of synthesizing the patterns to date. We found that (i) the strength of plant genetic effects can be quite high; however, the overall strength of genetic effects on most response variables declined as the levels of organization increased. (ii) Plant genetic effects varied such that introgression had a greater impact on individual phenotypes than extended effects on arthropods or microbes/fungi. By contrast, the greatest effects of genotypic diversity were on arthropods. (iii) Plant genetic effects were greater on above-ground versus below-ground processes, but there was no difference between terrestrial and aquatic environments. (iv) The strength of the effects of intraspecific genotypic diversity tended to be weaker than interspecific genetic introgression. (v) Although genetic effects generally decline across levels of organization, in some cases they do not, suggesting that specific organisms and/or processes may respond more than others to underlying genetic variation. Because patterns in the overall impacts of introgression and genotypic diversity were generally consistent across diverse study systems and consistent with theoretical expectations, these results provide generality for understanding the extended consequences of plant genetic variation across levels of organization, with evolutionary implications. PMID:19414474

  14. Monitoring plant bioremediation of volatile organic compounds (VOCs) using open path Fourier transform infrared (FT-IR) spectrometry

    SciTech Connect

    Hoffman, R.M.; Visser, V.P.; Davis, L.C.; Erickson, L.E.; Muralidharan, N.; Hammaker, R.M.; Fateley, W.G.

    1994-12-31

    This study addresses a viable and natural solution to the elimination of volatile organic compounds (VOCs), which are pollutants, through the bioremediation process. Plants and associated rhizosphere bacteria have the ability to bioremediate both volatile and non-volatile organic compounds. For volatile compounds, intersystem transfer by transpiration may be a matter for concern when plants interact with such materials. The authors have monitored, using FT-IR, the potential transfer from subsurface water in the presence of toluene-adapted alfalfa plants. These experiments show that the plants and/or their associated micro-organisms effectively degrade toluene so that potential intersystem transfer of VOCs by transpiration may be quite manageable with adapted plants. Presently, the authors are monitoring 1,1,1-trichloroethane (TCA), chloroform (CHCl{sub 3}), and, trichloroethylene (TCE) from the subsurface water and the gas phase above the plants. TCA does not show an indication of degradation, whereas TCE does. Methane is produced in the groundwater but not transferred to the atmosphere, indicating the presence of a consortium of methanogens and methanotrophs in this soil. The TCE presumably is the substrate for methane production based on chloride ion accumulation. The majority of the TCE must be degraded aerobically to yield CO{sub 2} in the vadose zone. The FT-IR spectrometer can quickly determine and analyze contaminants in the gas phase, groundwater and plant tissue.

  15. Nutrient allocation among plant organs across 13 tree species in three Bornean rain forests with contrasting nutrient availabilities.

    PubMed

    Aoyagi, Ryota; Kitayama, Kanehiro

    2016-07-01

    Allocation of nitrogen (N) and phosphorus (P) among plant organs is an important factor regulating growth rate, which is a key ecological process associated with plant life-history strategies. However, few studies have explored how N and P investment in photosynthetic (leaves) and non-photosynthetic (stems and roots) organs changes in relation to depletion of each element. We investigated nutrient concentrations of plant organs in relation to whole-plant nutrient concentration (total nutrient weight per total biomass) as an index of nutrient status of each individual using the saplings of the 13 species in three tropical rain forests with contrasting N and P availabilities (tropical evergreen forests and tropical heath forests). We found a steeper decrease in foliar N concentration than foliar P concentration with decreasing whole-plant nutrient concentration. Moreover, the steeper decrease in foliar N concentration was associated with relatively stable N concentration in stems, and vice versa for P. We suggest that the depletion of N is associated with a rapid dilution of foliar N because the cell walls in non-photosynthetic organs function as an N sink. On the other hand, these species can maintain foliar P concentration by decreasing stem P concentrations despites the depletion of P. Our results emphasize the significance of non-photosynthetic organs as an N sink for understanding the variation of foliar nutrient concentrations for the tree species in the three Bornean rain forests with different N and P availabilities. PMID:27056098

  16. Exudation of organic acids by a marsh plant and implications on trace metal availability in the rhizosphere of estuarine sediments

    NASA Astrophysics Data System (ADS)

    Mucha, Ana P.; Almeida, C. Marisa R.; Bordalo, Adriano A.; Vasconcelos, M. Teresa S. D.

    2005-10-01

    The aim of this work was to identify a variety of low molecular weight organic acids exuded by the sea rush Juncus maritimus collected at two locations with different sediment characteristics (sandy and muddy) and to examine whether specific differences in physico-chemical sediment characteristics influenced plant exudation. Just after collection, plant roots were rinsed and put in contact with deionised water for 2 h. In the obtained solution the organic acids, exuded by the plants, were determined by high performance liquid chromatography. Juncus maritimus was shown to be capable of releasing malonate and oxalate. Sediments and rhizosediments (sediment in contact with the plant roots and rhizomes, corresponding to the area of higher belowground biomass) from the areas where the plants had been collected were characterised in terms of physical and chemical composition, including acid volatile sulphide and total-recoverable metals (Pb, Cr, Cu, Zn, Ni and Cd). It was found that the extent of exudation varied markedly between sites. The identified organic acids were used as extractants of metals from sediments and rhizosediments and the results were compared with those provided by a very commonly used sequential extraction approach, which was carried out in parallel. This work demonstrates that J. maritimus can release organic compounds that can act as complexing agents of trace metal and therefore organic exudates should be accounted for when dealing with estuarine environment quality.

  17. Plant cyclins: a unified nomenclature for plant A-, B- and D-type cyclins based on sequence organization.

    PubMed

    Renaudin, J P; Doonan, J H; Freeman, D; Hashimoto, J; Hirt, H; Inzé, D; Jacobs, T; Kouchi, H; Rouzé, P; Sauter, M; Savouré, A; Sorrell, D A; Sundaresan, V; Murray, J A

    1996-12-01

    The comparative analysis of a large number of plant cyclins of the A/B family has recently revealed that plants possess two distinct B-type groups and three distinct A-type groups of cyclins. Despite earlier uncertainties, this large-scale comparative analysis has allowed an unequivocal definition of plant cyclins into either A or B classes. We present here the most important results obtained in this study, and extend them to the case of plant D-type cyclins, in which three groups are identified. For each of the plant cyclin groups, consensus sequences have been established and a new, rational, plant-wide naming system is proposed in accordance with the guidelines of the Commission on Plant Gene Nomenclature. This nomenclature is based on the animal system indicating cyclin classes by an upper-case roman letter, and distinct groups within these classes by an arabic numeral suffix. The naming of plant cyclin classes is chosen to indicate homology to their closest animal class. The revised nomenclature of all described plant cyclins is presented, with their classification into groups CycA1, CycA2, CycA3, CycB1, CycB2, CycD1, CycD2 and CycD3. PMID:9002599

  18. Elevated CO2 increases plant uptake of organic and inorganic N in the desert shrub Larrea tridentata.

    PubMed

    Jin, Virginia L; Evans, R D

    2010-05-01

    Resource limitations, such as the availability of soil nitrogen (N), are expected to constrain continued increases in plant productivity under elevated atmospheric carbon dioxide (CO(2)). One potential but under-studied N source for supporting increased plant growth under elevated CO(2) is soil organic N. In arid ecosystems, there have been no studies examining plant organic N uptake to date. To assess the potential effects of elevated atmospheric CO(2) on plant N uptake dynamics, we quantified plant uptake of organic and inorganic N forms in the dominant desert shrub Larrea tridentata under controlled environmental conditions. Seedlings of L. tridentata were grown in the Mojave Desert (NV, USA) soils that had been continuously exposed to ambient or elevated atmospheric CO(2) for 8 years at the Nevada Desert FACE Facility. After 6 months of growth in environmentally controlled chambers under ambient (380 micromol mol(-1)) or elevated (600 micromol mol(-1)) CO(2), pots were injected with stable isotopically labeled sole-N sources ((13)C-[2]-(15)N glycine, (15)NH(4) (+), or (15)NO(3) (-)) and moved back to their respective chambers for the remainder of the study. Plants were destructively harvested at 0, 2, 10, 24, and 49 days. Plant uptake of soil N derived from glycine, NH(4) (+), and NO(3) (-) increased under elevated CO(2) at days 2 and 10. Further, root uptake of organic N as glycine occurred as intact amino acid within the first hour after N treatment, indicated by approximately 1:1 M enrichment ratios of (13)C:(15)N. Plant N uptake responses to elevated CO(2) are often species-specific and could potentially shift competitive interactions between co-occurring species. Thus, physiological changes in root N uptake dynamics coupled with previously observed changes in the availability of soil N resources could impact plant community structure as well as ecosystem nutrient cycling under increasing atmospheric CO(2) levels in the Mojave Desert. PMID:20094733

  19. Iron production maintenance effectiveness system

    SciTech Connect

    Augstman, J.J.

    1996-12-31

    In 1989, an internal study in the Coke and Iron Maintenance Department identified the opportunities available to increase production, by decreasing unscheduled maintenance delays from 4.6%. A five year front loaded plan was developed, and presented to the company president. The plan required an initial investment of $1.4 million and a conservative break-even point was calculated to be 2.5 years. Due to budget restraints, it would have to be self-funded, i.e., generate additional production or savings, to pay for the program. The program began in 1991 at number 2 coke plant and the blast furnaces. This paper will describe the Iron Production Maintenance Effectiveness System (ME), which began with the mechanical and pipefitting trades.

  20. Tracing subsoil organic matter compositional changes by radiocarbon and plant leaf wax distributional changes

    NASA Astrophysics Data System (ADS)

    John, Stephan; Angst, Gerrit; Mueller, Carsten W.; Heinze, Stefanie; Marschner, Bernd; Rethemeyer, Janet

    2014-05-01

    The carbon pool in subsoils is thought to be considerably larger than in the upper 30 cm. However, factors like turnover, stabilization and distribution of organic matter (OM) are less well understood than in topsoils. The investigation of changes in OM composition with depth enables a better understanding of the peculiarity of subsoil OM in contrast to the already extensively studied topsoil OM. Analysis of long chained n-alkanes and n-fatty acids in soil profiles sampled in high resolution, combined with radiocarbon data of bulk soil, is a tool to demonstrate spatial distribution and the degradation of plant leaf wax-derived material as a defined source of soil organic. We analysed the OM in 3.15 m long soil transects under an even aged European beech (Fagus sylvatica L.) forest in Northern Germany (Grinderwald, Lower Saxony) for lipid and radiocarbon analysis. Samples were taken from a grid raster with eight sampling points increasing in distance to the main tree (45cm grid dimension) and from five depths (10, 35, 60, 85, 110 cm) resulting 40 samples per transect. Organic carbon contents in the podzolic Cambisol decrease from 1.69 % in the A-horizon to 0.02 % in the C-horizon at 110 cm depth. The distribution of organic carbon contents shows no significant trend with increasing distance to the beeches in all transects. We compare the distribution of long-chain n-alkanes (C27, C29 and C31) and n-fatty acids (>C20), known as components mainly derived from leaf waxes of higher plants, in the different transect/depth intervals. Distributional and quantitative changes in the transects, combined with bulk soil 14C-analyses, reflecting apparent mean residence time of OM, are used to identify how fast OM is degraded from surface to subsoil horizons. Furthermore, spatial OM heterogeneity in the transects is investigated. We expect a more significant heterogeneity in the lipid distribution and nearly similar decreasing contents for n-alkanes as well as n-fatty acids

  1. The safety assessment of food ingredients derived from plant cell, tissue and organ cultures: a review.

    PubMed

    Murthy, Hosakatte Niranjana; Georgiev, Milen I; Park, So-Young; Dandin, Vijayalaxmi S; Paek, Kee-Yoeup

    2015-06-01

    Plant cell, tissue and organ cultures (PCTOC) have become an increasingly attractive alternative for the production of various high molecular weight molecules which are used as flavourings, fragrances, colouring agents and food additives. Although PCTOC products are cultivated in vitro in a contamination free environment, the raw material produced from PCTOC may contain many components apart from the target compound. In some cases, PCTOC raw materials may also carry toxins, which may be naturally occurring or accumulated during the culture process. Assessment of the safety of PCTOC products is, therefore, a priority of the biotech industries involved in their production. The safety assessment involves the evaluation of starting material, production process and the end product. Before commercialisation, PCTOC products should be evaluated for their chemical and biological properties, as well as for their toxicity. In this review, measures and general criteria for biosafety evaluation of PCTOC products are addressed and thoroughly discussed. PMID:25624252

  2. Photocatalytic: oxidation of volatile organic compounds present in airborne environment adjacent to sewage treatment plants.

    PubMed

    Raillard, C; Héquet, V; Le Cloirec, P; Legrand, J

    2004-01-01

    Emissions of volatile organic compounds (VOCs) from wastewater in municipal sewage or industrial wastewater treatment plants are often overlooked as sources of exposure to hazardous substances. The impact of such emissions on local airborne environments represents a growing source of scientific, toxicological and public health interest. Actually, VOCs are suspected to be quite dangerous for human health. Some of them belong to the family of odorous compounds and can cause serious annoyance in the neighbourhood of the emission sources. A way to remove VOCs released from sewers and wastewater treatment facilities could be to degrade them by photocatalytic oxidation. TiO2-based photocatalysts are known to be efficient for this kind of application. In the present work TiO2 P25 Degussa was deposited on glass supports. These materials were tested for the degradation of butanone-2 in a photocatalytic reactor. The influence of water vapour (relative humidity) was shown using the Langmuir-Hinshelwood kinetic model. PMID:14979545

  3. Plant diversity effects on leaching of nitrate, ammonium, and dissolved organic nitrogen from an experimental grassland

    NASA Astrophysics Data System (ADS)

    Leimer, Sophia; Oelmann, Yvonne; Wirth, Christian; Wilcke, Wolfgang

    2014-05-01

    Leaching of nitrogen (N) from soil represents a resource loss and, in particular leaching of nitrate, can threaten drinking water quality. As plant diversity leads to a more exhaustive resource use, we investigated the effects of plant species richness, functional group richness, and the presence of specific functional groups on nitrate, ammonium, dissolved organic N (DON), and total dissolved N (TDN) leaching from an experimental grassland in the first 4 years after conversion from fertilized arable land to unfertilized grassland. The experiment is located in Jena, Germany, and consists of 82 plots with 1, 2, 4, 8, 16, or 60 plant species and 1-4 functional groups (legumes, grasses, non-leguminous tall herbs, non-leguminous small herbs). Nitrate, ammonium, and TDN concentrations in soil solution in the 0-0.3 m soil layer were measured every second week during 4 years on 62 plots and DON concentrations were calculated as difference between TDN and inorganic N. Missing concentrations in soil solution were estimated using a Bayesian statistical model. Downward water fluxes (DF) per plot from the 0-0.3 m soil layer were simulated in weekly resolution with a water balance model in connection with a Bayesian model for simulating missing soil water content measurements. To obtain annual nitrate, ammonium, and DON leaching from the 0-0.3 m soil layer per plot, we multiplied the respective concentrations in soil solution with DF and aggregated the data to annual sums. TDN leaching resulted from summation of nitrate, ammonium, and DON leaching. DON leaching contributed most to TDN leaching, particularly in plots without legumes. Dissolved inorganic N leaching in this grassland was dominated by nitrate. The amount of annual ammonium leaching was small and little influenced by plant diversity. Species richness affected DON leaching only in the fourth and last investigated year, possibly because of a delayed soil biota effect that increased microbial transformation of organic

  4. 14 CFR 43.17 - Maintenance, preventive maintenance, and alterations performed on U.S. aeronautical products by...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... aeronautical product under airworthiness regulation by Transport Canada Civil Aviation. U.S. aeronautical... person holding a valid Transport Canada Civil Aviation Maintenance Engineer license and appropriate... this section. (2) A Transport Canada Civil Aviation Approved Maintenance Organization (AMO)...

  5. 14 CFR 43.17 - Maintenance, preventive maintenance, and alterations performed on U.S. aeronautical products by...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... aeronautical product under airworthiness regulation by Transport Canada Civil Aviation. U.S. aeronautical... person holding a valid Transport Canada Civil Aviation Maintenance Engineer license and appropriate... this section. (2) A Transport Canada Civil Aviation Approved Maintenance Organization (AMO)...

  6. 14 CFR 43.17 - Maintenance, preventive maintenance, and alterations performed on U.S. aeronautical products by...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... aeronautical product under airworthiness regulation by Transport Canada Civil Aviation. U.S. aeronautical... person holding a valid Transport Canada Civil Aviation Maintenance Engineer license and appropriate... this section. (2) A Transport Canada Civil Aviation Approved Maintenance Organization (AMO)...

  7. Soil Organic Matter Quality of an Oxisol Affected by Plant Residues and Crop Sequence under No-Tillage

    NASA Astrophysics Data System (ADS)

    Cora, Jose; Marcelo, Adolfo

    2013-04-01

    Plant residues are considered the primarily resource for soil organic matter (SOM) formation and the amounts and properties of plant litter are important controlling factors for the SOM quality. We determined the amounts, quality and decomposition rate of plant residues and the effects of summer and winter crop sequences on soil organic C (TOC) content, both particulate organic C (POC) and mineral-associated organic C (MOC) pools and humic substances in a Brazilian Rhodic Eutrudox soil under a no-tillage system. The organic C analysis in specifics pools used in this study was effective and should be adopted in tropical climates to evaluate the soil quality and the sustainability of various cropping systems. Continuous growth of soybean (Glycine max L. Merrill) on summer provided higher contents of soil POC and continuous growth of maize (Zea mays L.) provided higher soil humic acid and MOC contents. Summer soybean-maize rotation provided the higher plant diversity, which likely improved the soil microbial activity and the soil organic C consumption. The winter sunn hemp (Crotalaria juncea L.), pigeon pea (Cajanus cajan (L.) Millsp), oilseed radish (Raphanus sativus L.) and pearl millet (Pennisetum americanum (L.) Leeke) enhanced the soil MOC, a finding that is attributable to the higher N content of the crop residue. Sunn hemp and pigeon pea provided the higher soil POC content. Sunn hemp showed better performance and positive effects on the SOM quality, making it a suitable winter crop choice for tropical conditions with a warm and dry winter.

  8. Influence of conventional and organic agricultural practices on the phenolic content in eggplant pulp: Plant-to-plant variation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consumer awareness, pesticide and fertilizer contaminations, and environmental concerns have resulted in increased demand for organically grown farm products. The present study evaluates the influence that organic versus conventional farming practices exert on the total phenolic content in eggplant...

  9. Insect maintenance and transmission.

    PubMed

    Kingdom, Heather

    2013-01-01

    Phytoplasmas are plant pathogens of huge economic importance due to responsibility for crop yield losses worldwide. Institutions around the world are trying to understand and control this yield loss at a time when food security is high on government agendas. In order to fully understand the mechanisms of phytoplasma infection and spread, more insect vector and phytoplasma colonies will need to be established for research worldwide. Rearing and study of these colonies is essential in the research and development of phytoplasma control measures. This chapter highlights general materials and methods for raising insect vector colonies and maintenance of phytoplasmas. Specific methods of rearing the maize leafhopper and maize bushy stunt phytoplasma and the aster leafhopper and aster yellows phytoplasma strain witches' broom are also included. PMID:22987405

  10. Reconnaissance of selected organic contaminants in effluent and ground water at fifteen municipal wastewater treatment plants in Florida, 1983- 84

    USGS Publications Warehouse

    Pruitt, J.B.; Troutman, D.E.; Irwin, G.A.

    1985-01-01

    Results of a 1983-84 reconnaissance of 15 municipal wastewater treatment plants in Florida indicated that effluent from most of the plants contains trace concentrations of volatile organic compounds. Chloroform was detected in the effluent at 11 of the 15 plants and its common occurrence was likely the result of chlorination. The maximum concentration of chloroform detected in the effluent sampled was 120 micrograms/L. Detectable concentrations of selected organophosphorus insecticides were also common. For example, diazinon was detected in the effluent at 12 of the 15 plants with a maximum concentration of 1.5 micrograms/L. Organochlorine insecticides, primarily lindane, were detected in the effluent at 8 of the 15 plants with a maximum concentration of 1.0 micrograms/L. Volatile compounds, primarily chloroform, were detected in water from monitor wells at four plants and organophosphorus insecticides, primarily diazinon, were present in the groundwater at three treatment plants. Organochlorine insecticides were not detected in any samples from monitor wells. Based on the limited data available, this cursory reconaissance suggests that the organic contaminants commonly occurring in the effluent of many of the treatment plants are not transported into the local groundwater. (Author 's abstract)

  11. A Comparative study of Volatile Organic Compounds from two desert plant species growing in Southern Arizona

    NASA Astrophysics Data System (ADS)

    Paasche, K. M.; Meyers, K.; Jardine, K.

    2012-12-01

    Throughout their lives, plants are subjected to a multitude of stressors, ranging from herbivory to changes in weather. In order to survive, plants have created an arsenal of volatile organic compounds (VOCs), including green leaf volatiles (GLVs) and aromatic compounds, to combat these stressors. In this study, two plant species, Baccharis salicifolia (Seep willow) and Dodonaea viscosa (Hopbush) were examined for isoprenoids, GLVs, and aromatic compound emissions. Although, the species are not related, they should share some emitted compounds as they can be seen growing in the same environment, though the majority of the emitted compounds should remain unique to each species type. Both the Seep willow, sampled in Catalina State Park, and the Hopbush, sampled at Biosphere 2, were sampled using a Teflon bag enclosure connected to an apex lite air-sampling device and a thermal desorption (TD) tube, which was used to collect the emitted compounds. TD tube samples were analyzed using a Unity 2 thermal desorption system, which was directly connected to a 5975C series gas chromatograph/electron impact mass spectrometer with a triple-axis detector. The major compounds emitted from the Seep willow were GLVs (Octanal, Decanal, and Nonanal) and aromatics (Benzoic acid, Benzaldehyde, 1,2,3-Trifluorobenzene, and Acetophenone). The major compounds emitted from the Hopbush were isoprene and monoterpenes (1R-α-Pinene, Limonene, and α-Phellandrene.) Our results show the two species emit completely different compounds from each other, which could indicate adaptive differences. The Hopbush may be a hardier species better adapted to the Arizona environment as isoprene and monoterpenes have been indicated in thermo tolerance. GLVs on the other hand indicate the Seep willow is under severe stress.

  12. Accumulation of plant small heat-stress proteins in storage organs.

    PubMed

    Lubaretz, Olga; Zur Nieden, Uta

    2002-06-01

    Plant small heat-stress proteins (sHSPs) have been shown to be expressed not only after exposure to elevated temperatures, but also at particular developmental stages such as embryogenesis, microsporogenesis, and fruit maturation. This paper presents new data on the occurrence of sHSPs in vegetative tissues, their tissue-specific distribution, and cellular localization. We have found sHSPs in 1-year-old twigs of Acer platanoides L. and Sambucus nigra L. and in the liana Aristolochia macrophylla Lamk. exclusively in the winter months. In tendrils of Aristolochia, sHSPs were localized in vascular cambium cells. After budding, in spring, these proteins were no longer present. Furthermore, accumulation of sHSPs was demonstrated in tubers and bulbs of Allium cepa L., Amaryllis ( Hippeastrum hybridum hort.), Crocus albiflorus L., Hyacinthus orientalis L., Narcissus pseudonarcissus L., Tulipa gesneriana L., and Solanum tuberosum L. (potato). In potato tubers and bulb scales of Narcissus the stress proteins were localized in the central vacuoles of storage parenchyma cells. In order to obtain more information on a possible functional correlation between storage proteins and sHSPs, the accumulation of both types of protein in tobacco seeds during seed ripening and germination was monitored. The expression of sHSPs and globulins started simultaneously at about the 17th day after anthesis. During seed germination the sHSPs disappeared in parallel with the storage proteins. Furthermore, in embryos of transgenic tobacco plants, which do not contain any protein bodies or storage proteins, no sHSPs were found. Thus, the occurrence of sHSPs in perennial plant storage organs seems to be associated with the presence of storage proteins. PMID:12029471

  13. Influence of two plant extracts on broilers performance, digestibility, and digestive organ size.

    PubMed

    Hernández, F; Madrid, J; García, V; Orengo, J; Megías, M D

    2004-02-01

    A 42-d trial was conducted to study the influence of 2 plant extracts on performance, digestibility, and digestive organ weights in broilers. The feeding program consisted of a starter diet until 21 d and a finisher diet until 42 d. There were 4 treatment groups: control; 10 ppm avilamycin (AB); 200 ppm essential oil extract (EOE) from oregano, cinnamon, and pepper; and 5,000 ppm Labiatae extract (LE) from sage, thyme, and rosemary. No differences in feed intake or feed conversion were observed. From 14 to 21 d of age, broilers fed the LE diet grew faster than the broilers fed the control or EOE feeds (68.8 vs. 63.9 and 61.6 g/d, respectively). Antibiotic and plant extract supplementation improved apparent whole-tract and ileal digestibility of the nutrients. For starter feed, LE supplementation improved apparent fecal digestibility of DM (P < 0.01), and all additives increased ether extract digestibility (P < 0.001). However, no effect was detected for CP digestibility (P > 0.1). At the ileal level, the AB, EOE, and LE supplementation of the starter feed increased DM and starch (P < 0.01) digestibility but not CP digestibility (P > 0.1). All additives improved apparent fecal digestibility of DM and CP of the finisher diet. No differences were observed for proventriculus, gizzard, liver, pancreas, or large or small intestine weight. In the present study, both plant extracts improved the digestibility of the feeds for broilers. The effect of different additives on digestibility improved the performance slightly, but this effect was not statistically significant. PMID:14979566

  14. Cyanide-resistant respiration in photosynthetic organs of freshwater aquatic plants. [Myriophyllum spicatum

    SciTech Connect

    Azcon-Bieto, J.; Murillo, J.; Penuelas, J.

    1987-07-01

    The rate and sensitivity to inhibitors (KCN and salicylhydroxamic acid(SHAM)) of respiratory oxygen uptake has been investigated in photosynthetic organs of several freshwater aquatic plant species. The oxygen uptake rates on a dry weigh basis of angiosperm leaves were generally higher than those of the corresponding stems. Leaves also had a higher chlorophyll content than stems. Respiration of leaves and stems of aquatic angiosperms was generally cyanide-resistant. The cyanide resistance of respiration of whole shoots of two aquatic bryophytes and an alga was lower. These results suggested that the photosynthetic tissues of aquatic plants have a considerable alternative pathway capacity. The angiosperm leaves generally showed the largest alternative path capacity. In all cases, the respiration rate of the aquatic plants studied was inhibited by SHAM alone by about 13 to 31%. These results were used for calculating the actual activities of the cytochrome and alternative pathways. These activities were generally higher in the leaves of angiosperms. The basal oxygen uptake rate of Myriophyllum spicatum leaves was greatly increased by CCCP, either in the presence or in the absence of substrates. These results suggest that respiration was limited by the adenylate system, and not by substrate availability. The increase in the respiratory rate by CCCP was due to a large increase in the activities of both the cytochrome and alternative pathways. The respiration rate of M. spicatum leaves in the presence of substrates was little inhibited by SHAM alone, but the SHAM-resistant rate (that is, the cytochrome path) was greatly stimulated by the further addition of CCCP. Similarly, the cyanide-resistant rate of O/sub 2/ uptake was also increased by the uncoupler.

  15. On the use of plant emitted volatile organic compounds for atmospheric chemistry simulation experiments

    NASA Astrophysics Data System (ADS)

    Kiendler-Scharr, A.; Hohaus, T.; Yu, Z.; Tillmann, R.; Kuhn, U.; Andres, S.; Kaminski, M.; Wegener, R.; Novelli, A.; Fuchs, H.; Wahner, A.

    2015-12-01

    Biogenic volatile organic compounds (BVOC) contribute to about 90% of the emitted VOC globally with isoprene being one of the most abundant BVOC (Guenther 2002). Intensive efforts in studying and understanding the impact of BVOC on atmospheric chemistry were undertaken in the recent years. However many uncertainties remain, e.g. field studies have shown that in wooded areas measured OH reactivity can often not be explained by measured BVOC and their oxidation products (e.g. Noelscher et al. 2012). This discrepancy may be explained by either a lack of understanding of BVOC sources or insufficient understanding of BVOC oxidation mechanisms. Plants emit a complex VOC mixture containing likely many compounds which have not yet been measured or identified (Goldstein and Galbally 2007). A lack of understanding BVOC sources limits bottom-up estimates of secondary products of BVOC oxidation such as SOA. Similarly, the widespread oversimplification of atmospheric chemistry in simulation experiments, using single compound or simple BVOC mixtures to study atmospheric chemistry processes limit our ability to assess air quality and climate impacts of BVOC. We will present applications of the new extension PLUS (PLant chamber Unit for Simulation) to our atmosphere simulation chamber SAPHIR. PLUS is used to produce representative BVOC mixtures from direct plant emissions. We will report on the performance and characterization of the newly developed chamber. As an exemplary application, trees typical of a Boreal forest environment were used to compare OH reactivity as directly measured by LIF to the OH reactivity calculated from BVOC measured by GC-MS and PTRMS. The comparison was performed for both, primary emissions of trees without any influence of oxidizing agents and using different oxidation schemes. For the monoterpene emitters investigated here, we show that discrepancies between measured and calculated total OH reactivity increase with increasing degree of oxidation

  16. Myosin-dependent endoplasmic reticulum motility and F-actin organization in plant cells

    PubMed Central

    Ueda, Haruko; Yokota, Etsuo; Kutsuna, Natsumaro; Shimada, Tomoo; Tamura, Kentaro; Shimmen, Teruo; Hasezawa, Seiichiro; Dolja, Valerian V.; Hara-Nishimura, Ikuko

    2010-01-01

    Plants exhibit an ultimate case of the intracellular motility involving rapid organelle trafficking and continuous streaming of the endoplasmic reticulum (ER). Although it was long assumed that the ER dynamics is actomyosin-driven, the responsible myosins were not identified, and the ER streaming was not characterized quantitatively. Here we developed software to generate a detailed velocity-distribution map for the GFP-labeled ER. This map revealed that the ER in the most peripheral plane was relatively static, whereas the ER in the inner plane was rapidly streaming with the velocities of up to ∼3.5 μm/sec. Similar patterns were observed when the cytosolic GFP was used to evaluate the cytoplasmic streaming. Using gene knockouts, we demonstrate that the ER dynamics is driven primarily by the ER-associated myosin XI-K, a member of a plant-specific myosin class XI. Furthermore, we show that the myosin XI deficiency affects organization of the ER network and orientation of the actin filament bundles. Collectively, our findings suggest a model whereby dynamic three-way interactions between ER, F-actin, and myosins determine the architecture and movement patterns of the ER strands, and cause cytosol hauling traditionally defined as cytoplasmic streaming. PMID:20351265

  17. Spatial organization and correlation properties quantify structural changes on mesoscale of parenchymatous plant tissue

    NASA Astrophysics Data System (ADS)

    Valous, N. A.; Delgado, A.; Drakakis, K.; Sun, D.-W.

    2014-02-01

    The study of plant tissue parenchyma's intercellular air spaces contributes to the understanding of anatomy and physiology. This is challenging due to difficulty in making direct measurements of the pore space and the complex mosaic of parenchymatous tissue. The architectural complexity of pore space has shown that single geometrical measurements are not sufficient for characterization. The inhomogeneity of distribution depends not only on the percentage content of phase, but also on how the phase fills the space. The lacunarity morphometric, as multiscale measure, provides information about the distribution of gaps that correspond to degree of spatial organization in parenchyma. Additionally, modern theories have suggested strategies, where the focus has shifted from the study of averages and histograms to the study of patterns in data fluctuations. Detrended fluctuation analysis provides information on the correlation properties of the parenchyma at different spatial scales. The aim is to quantify (with the aid of the aforementioned metrics), the mesostructural changes—that occur from one cycle of freezing and thawing—in the void phase of pome fruit parenchymatous tissue, acquired with X-ray microcomputed tomography. Complex systems methods provide numerical indices and detailed insights regarding the freezing-induced modifications upon the arrangement of cells and voids. These structural changes have the potential to lead to physiological disorders. The work can further stimulate interest for the analysis of internal plant tissue structures coupled with other physico-chemical processes or phenomena.

  18. Spatial organization and correlation properties quantify structural changes on mesoscale of parenchymatous plant tissue

    SciTech Connect

    Valous, N. A.; Delgado, A.; Sun, D.-W.; Drakakis, K.

    2014-02-14

    The study of plant tissue parenchyma's intercellular air spaces contributes to the understanding of anatomy and physiology. This is challenging due to difficulty in making direct measurements of the pore space and the complex mosaic of parenchymatous tissue. The architectural complexity of pore space has shown that single geometrical measurements are not sufficient for characterization. The inhomogeneity of distribution depends not only on the percentage content of phase, but also on how the phase fills the space. The lacunarity morphometric, as multiscale measure, provides information about the distribution of gaps that correspond to degree of spatial organization in parenchyma. Additionally, modern theories have suggested strategies, where the focus has shifted from the study of averages and histograms to the study of patterns in data fluctuations. Detrended fluctuation analysis provides information on the correlation properties of the parenchyma at different spatial scales. The aim is to quantify (with the aid of the aforementioned metrics), the mesostructural changes—that occur from one cycle of freezing and thawing—in the void phase of pome fruit parenchymatous tissue, acquired with X-ray microcomputed tomography. Complex systems methods provide numerical indices and detailed insights regarding the freezing-induced modifications upon the arrangement of cells and voids. These structural changes have the potential to lead to physiological disorders. The work can further stimulate interest for the analysis of internal plant tissue structures coupled with other physico-chemical processes or phenomena.

  19. Volatiles emission patterns of different plant organs and pollen of Citrus limon.

    PubMed

    Flamini, Guido; Tebano, Marianna; Cioni, Pier Luigi

    2007-04-18

    The volatiles emitted in vivo by different plant parts of Citrus limon (Rutaceae) have been identified by mean of head space-solid phase micro extraction (HS-SPME) and gas chromatography coupled with mass spectrometry (GC-MS) analyses. In particular, the profiles of flower buds, mature flowers, petals, stamens, gynaecium, pericarp of unripe and ripe fruits, young and adult leaves and pollen have been examined. Furthermore, the essential oil obtained from expression of ripe pericarp was studied. Volatiles were produced in distinctive amounts by the different plant organs, creating an interesting contrast, particularly within the flower parts: the highest amount of limonene (62.5%) was emitted by gynaecium, followed by stamens (22.9%) and petals (3.1%). Pollen did not produce limonene at all. The same compound is contained in higher amounts in the young leaves than in old ones (65.3% versus 30.1%). A possible defensive role of limonene and other volatiles, mainly terpene aldehydes, produced by young leaves has been hypothesized. PMID:17397661

  20. Source location and characterization of volatile organic compound emissions at a petrochemical plant in Kaohsiung, Taiwan.

    PubMed

    Chen, Chin-Liang; Fang, Hung Yuan; Shu, Chi-Min

    2005-10-01

    This paper elucidated a novel approach to locating volatile organic compound (VOC) emission sources and characterizing their VOCs by database and contour plotting. The target of this survey was a petrochemical plant in Linyan, Kaohsiung County, Taiwan. Samples were taken with canisters from 25 sites inside this plant, twice per season, and analyzed by gas chromatography-mass spectrometry. The survey covered 1 whole year. By consolidated into a database, the data could be readily retrieved, statistically analyzed, and clearly presented in both table and graph forms. It followed from the cross-analysis of the database that the abundant types of VOCs were alkanes, alkenes/dienes, and aromatics, all of which accounted for 99% of total VOCs. By contour plotting, the emission sources for alkanes, aromatics, and alkenes/ dienes were successfully located. Through statistical analysis, the database could provide the range and 90% confidence interval of each species from each emission source. Both alkanes and alkene/dienes came from tank farm and naphtha cracking units and were mainly composed of C3-C5 members. Regarding aromatics, benzene, toluene, and xylenes were the primary species; they were emitted from tank farm, aromatic units, and xylene units. PMID:16295274