Science.gov

Sample records for determining economic viability

  1. Demonstration of a Probabilistic Technique for the Determination of Economic Viability of Very Large Transport Configurations

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri N.

    1998-01-01

    Over the past few years, modem aircraft design has experienced a paradigm shift from designing for performance to designing for affordability. This report contains a probabilistic approach that will allow traditional deterministic design methods to be extended to account for disciplinary, economic, and technological uncertainty. The probabilistic approach was facilitated by the Fast Probability Integration (FPI) technique; a technique which allows the designer to gather valuable information about the vehicle's behavior in the design space. This technique is efficient for assessing multi-attribute, multi-constraint problems in a more realistic fashion. For implementation purposes, this technique is applied to illustrate how both economic and technological uncertainty associated with a Very Large Transport aircraft concept may be assessed. The assessment is evaluated with the FPI technique to determine the cumulative probability distributions of the design space, as bound by economic objectives and performance constraints. These distributions were compared to established targets for a comparable large capacity aircraft, similar in size to the Boeing 747-400. The conventional baseline configuration design space was determined to be unfeasible and marginally viable, motivating the infusion of advanced technologies, including reductions in drag, specific fuel consumption, wing weight, and Research, Development, Testing, and Evaluation costs. The resulting system design space was qualitatively assessed with technology metric "k" factors. The infusion of technologies shifted the VLT design into regions of feasibility and greater viability. The study also demonstrated a method and relationship by which the impact of new technologies may be assessed in a more system focused approach.

  2. Economic viability of anaerobic digestion

    SciTech Connect

    Wellinger, A.

    1996-01-01

    The industrial application of anaerobic digestion is a relatively new, yet proven waste treatment technology. Anaerobic digestion reduces and upgrades organic waste, and is a good way to control air pollution as it reduces methane and nitrous gas emissions. For environmental and energy considerations, anaerobic digestion is a nearly perfect waste treatment process. However, its economic viability is still in question. A number of parameters - type of waste (solid or liquid), digester system, facility size, product quality and end use, environmental requirements, cost of alternative treatments (including labor), and interest rates - define the investment and operating costs of an anaerobic digestion facility. Therefore, identical facilities that treat the same amount and type of waste may, depending on location, legislation, and end product characteristics, reveal radically different costs. A good approach for evaluating the economics of anaerobic digestion is to compare it to treatment techniques such as aeration or conventional sewage treatment (for industrial wastewater), or composting and incineration (for solid organic waste). For example, the cost (per ton of waste) of in-vessel composting with biofilters is somewhat higher than that of anaerobic digestion, but the investment costs 1 1/2 to 2 times more than either composting or anaerobic digestion. Two distinct advantages of anaerobic digestion are: (1) it requires less land than either composting or incinerating, which translates into lower costs and milder environmental and community impacts (especially in densely populated areas); and (2) it produces net energy, which can be used to operate the facility or sold to nearby industries.

  3. 30 CFR 203.68 - What pre-application costs will MMS consider in determining economic viability?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Development and Expansion Projects § 203.68 What pre-application costs will MMS consider in determining... development project, or an expansion project can become economic with full relief (see § 203.67). (3) Not... expansion project economic (see § 203.69(c)). (4) Include sunk costs for the project discovery well on...

  4. 30 CFR 203.68 - What pre-application costs will BSEE consider in determining economic viability?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... field, a development project, or an expansion project can become economic with full relief (see § 203.67... project, or an expansion project economic (see § 203.69(c)). (4) Include sunk costs for the project discovery well on each lease, Whether a development project or an expansion project needs relief to...

  5. 30 CFR 203.68 - What pre-application costs will BSEE consider in determining economic viability?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... field, a development project, or an expansion project can become economic with full relief (see § 203.67... project, or an expansion project economic (see § 203.69(c)). (4) Include sunk costs for the project discovery well on each lease, Whether a development project or an expansion project needs relief to...

  6. 30 CFR 203.68 - What pre-application costs will BSEE consider in determining economic viability?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... field, a development project, or an expansion project can become economic with full relief (see § 203.67... project, or an expansion project economic (see § 203.69(c)). (4) Include sunk costs for the project discovery well on each lease, Whether a development project or an expansion project needs relief to...

  7. 30 CFR 203.68 - What pre-application costs will MMS consider in determining economic viability?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Sulfur General Royalty Relief for Pre-Act Deep Water Leases and for Development and Expansion Projects... economic. (2) Not include sunk costs Whether an authorized field, a development project, or an expansion... suspension volume is necessary to make the field, a development project, or an expansion project...

  8. Economic viability of beef cattle grazing systems under prolonged drought

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prolonged drought in the Southern Great Plains of the USA in recent years has raised concerns about vulnerability of beef cattle grazing systems under adverse climate change. To help address the economic viability of beef grazing operations in the Southern Great Plains, this paper provides an econom...

  9. Proof of Economic Viability of Blended Learning Business Models

    ERIC Educational Resources Information Center

    Druhmann, Carsten; Hohenberg, Gregor

    2014-01-01

    The discussion on economically sustainable business models with respect to information technology is lacking in many aspects of proven approaches. In the following contribution the economic viability is valued based on a procedural model for design and evaluation of e-learning business models in the form of a case study. As a case study object a…

  10. Economic Viability of Brewery Spent Grain as a Biofuel

    SciTech Connect

    Morrow, Charles

    2016-01-01

    This report summarizes an investigation into the technical feasibility and economic viability of use grain wastes from the beer brewing process as fuel to generate the heat needed in subsequent brewing process. The study finds that while use of spent grain as a biofuel is technically feasible, the economics are not attractive. Economic viability is limited by the underuse of capital equipment. The investment in heating equipment requires a higher utilization that the client brewer currently anticipates. It may be possible in the future that changing factors may swing the decision to a more positive one.

  11. Economic and financial viability of small-scale dairy systems in central Mexico: economic scenario 2010-2018.

    PubMed

    Posadas-Domínguez, R R; Callejas-Juárez, N; Arriaga-Jordán, C M; Martínez-Castañeda, F E

    2016-12-01

    A simulation Monte Carlo model was used to assess the economic and financial viability of 130 small-scale dairy farms in central Mexico, through a Representative Small-Scale Dairy Farm. Net yields were calculated for a 9-year planning horizon by means of simulated values for the distribution of input and product prices taking 2010 as base year and considering four scenarios which were compared against the scenario of actual production. The other scenarios were (1) total hiring in of needed labour; (2) external purchase of 100 % of inputs and (3) withdrawal of subsidies to production. A stochastic modelling approach was followed to determine the scenario with the highest economic and financial viability. Results show a viable economic and financial situation for the real production scenario, as well as the scenarios for total hiring of labour and of withdrawal of subsidies, but the scenario when 100 % of feed inputs for the herd are bought-in was not viable.

  12. 30 CFR 203.85 - What is in an economic viability and relief justification report?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... economic viability and relief justification report must contain the following items for an oil and gas lease. (a) Economic assumptions we provide which include: (1) Starting oil and gas prices; (2) Real... INTERIOR MINERALS REVENUE MANAGEMENT RELIEF OR REDUCTION IN ROYALTY RATES OCS Oil, Gas, and Sulfur...

  13. An advanced concept that promises ecological and economic viability

    NASA Technical Reports Server (NTRS)

    Wright, B. R.; Sedgwick, T. A.; Urie, D. M.

    1976-01-01

    The actuality of supersonic commercial service being provided by Concorde is demonstrating to the world the advantages offered by supersonic travel for both business and recreation. Public acceptance will gradually and persistently stimulate interest to proceed with a second generation design that meets updated economic and ecological standards. It is estimated that this concept could operate profitably on world-wide routes with a revenue structure based upon economy fares. Airplanes will meet all present day ecological requirements regarding noise and emissions.

  14. Regional Economic Integration in the Developing World: Historical Trends at the Future Viability

    DTIC Science & Technology

    1994-01-01

    NPS-NS-94-001 NAVAL POSTGRADUATE SCHOOL S.MONTEREY, CALIFORNIA CO. 04 S~DTIC I ELECTE i SMAY 0419941 __- REGIONAL ECONOMIC INTEGRATION IN TEDVLPN...assijiuaw~n) REGIONAL ECONOMIC INTrEGRATION INT ITiET IIRI) WORLD: HISTORICAL TRENDS AND FUT[URE VIABILITY 12. PERSONAL AU IHOR(S) STEPHEN G. BROOKS I.1a...This study seeks to analyze the resurgence of regional economic integration efforts in the developing world. Economic integration is not a new

  15. Toward an integrated approach to nutritional quality, environmental sustainability, and economic viability: research and measurement gaps.

    PubMed

    Herforth, Anna; Frongillo, Edward A; Sassi, Franco; Mclean, Mireille Seneclauze; Arabi, Mandana; Tirado, Cristina; Remans, Roseline; Mantilla, Gilma; Thomson, Madeleine; Pingali, Prabhu

    2014-12-01

    Nutrition is affected by numerous environmental and societal causes. This paper starts with a simple framework based on three domains: nutritional quality, economic viability, and environmental sustainability, and calls for an integrated approach in research to simultaneously account for all three. It highlights limitations in the current understanding of each domain, and how they influence one another. Five research topics are identified: measuring the three domains (nutritional quality, economic viability, environmental sustainability); modeling across disciplines; furthering the analysis of food systems in relation to the three domains; connecting climate change and variability to nutritional quality; and increasing attention to inequities among population groups in relation to the three domains. For an integrated approach to be developed, there is a need to identify and disseminate available metrics, modeling techniques, and tools to researchers, practitioners, and policy makers. This is a first step so that a systems approach that takes into account potential environmental and economic trade-offs becomes the norm in analyzing nutrition and food-security patterns. Such an approach will help fill critical knowledge gaps and will guide researchers seeking to define and address specific research questions in nutrition in their wider socioeconomic and environmental contexts.

  16. The Potential of Energy Storage Systems with Respect to Generation Adequacy and Economic Viability

    NASA Astrophysics Data System (ADS)

    Bradbury, Kyle Joseph

    Intermittent energy resources, including wind and solar power, continue to be rapidly added to the generation fleet domestically and abroad. The variable power of these resources introduces new levels of stochasticity into electric interconnections that must be continuously balanced in order to maintain system reliability. Energy storage systems (ESSs) offer one potential option to compensate for the intermittency of renewables. ESSs for long-term storage (1-hour or greater), aside from a few pumped hydroelectric installations, are not presently in widespread use in the U.S. The deployment of ESSs would be most likely driven by either the potential for a strong internal rate of return (IRR) on investment and through significant benefits to system reliability that independent system operators (ISOs) could incentivize. To assess the potential of ESSs three objectives are addressed. (1) Evaluate the economic viability of energy storage for price arbitrage in real-time energy markets and determine system cost improvements for ESSs to become attractive investments. (2) Estimate the reliability impact of energy storage systems on the large-scale integration of intermittent generation. (3) Analyze the economic, environmental, and reliability tradeoffs associated with using energy storage in conjunction with stochastic generation. First, using real-time energy market price data from seven markets across the U.S. and the physical parameters of fourteen ESS technologies, the maximum potential IRR of each technology from price arbitrage was evaluated in each market, along with the optimal ESS system size. Additionally, the reductions in capital cost needed to achieve a 10% IRR were estimated for each ESS. The results indicate that the profit-maximizing size of an ESS is primarily determined by its technological characteristics (round-trip charge/discharge efficiency and self-discharge) and not market price volatility, which instead increases IRR. This analysis demonstrates

  17. Economic viability of the Saudi Arabian petrochemical industry: methanol as a case study

    SciTech Connect

    Al-Salem, A.M.

    1987-01-01

    In the pursuit of the diversification strategy, Saudi planners invested a sizable amount of oil surplus in export-oriented petrochemical projects at Jubail and Yanbu. For this strategy to be realized, the projects must be economically viable. Economic viability entails the presence of petrochemical plants that are self-sustaining and self-perpetuating in the long run without state subsidies. In view of the projects, heavy reliance on state subsidies along with their location in a remote area, far from the source of demand, it is hypothesized that, barring a significant shift in the development strategy, a dynamic industrial sector focusing on the development of the petrochemical industry is unlikely to emerge in Saudi Arabia and that the export-led growth strategy that accords it a key role in the nation's development is not likely to prove viable. In verifying the hypothesis, a comparative cost analysis was conducted comparing the cost structure at the Ibn-Sina methanol plant to a similar plant in Alberta, Canada. According to the authors forecast of methanol revenues and costs, the Saudi petrochemical industry exemplified by the methanol project emerges to be as a net absorber of rather than contributor to the nation's financial resources and in this regard appears to impede the process of capital formation and economic growth.

  18. A versatile assay for the accurate, time-resolved determination of cellular viability.

    PubMed

    Amano, Toyoki; Hirasawa, Ken ichi; O'Donohue, Michael J; Pernolle, Jean Claude; Shioi, Yuzo

    2003-03-01

    A convenient and versatile method for the accurate, time-resolved determination of cellular viability has been developed. The conventional viability indicator fluorescein diacetate (FDA), which is converted to the fluorescent compound fluorescein in living cells, was employed as a viability probe. Fluorescence emission from cells was measured using a spectrofluorimeter equipped with a magnetic stirrer. Using this assay cell suspensions exhibiting densities in the range 0.5 x 10(5) to 2.0 x 10(5) cells displayed a linear response when FDA concentrations less than 12 micro M were employed. To calibrate the method, viability standards were elaborated using different proportions of living and dead cells, and a correlation coefficient for the viability of tobacco BY-2 suspensions was calculated as 0.998. This viability assay was also found to be applicable to Chlamydomonas reinhardtii and Arabidopsis thaliana cultured cells. Using this cell viability assay, kinetic analyses of cell death could be performed. Using the proteinaceous elicitor from Phytophthora cryptogea, cryptogein, to induce cell death in tobacco cell suspensions, values for the maximum velocity of death induction rate (V(max)) and the LD50 (half-maximal velocity or k(1/2)) were calculated as 17.2 (% death/h) and 65 nM, respectively.

  19. Evaluating the Economic Viability of Universities by Using Price-Level-Adjusted Financial Data. Faculty Working Papers.

    ERIC Educational Resources Information Center

    Chan, James L.; Snyder, Gerald E.

    Ways in which the external financial disclosures by universities may evaluate institutional economic viability are demonstrated. It is argued that the evaluation should take into account the effect of inflation and activity level. The evaluation model requires several years' information about revenues (general operating fund), the impact of…

  20. Potential Economic Viability of Two Proposed Rifapentine-Based Regimens for Treatment of Latent Tuberculosis Infection

    PubMed Central

    Holland, David P.; Sanders, Gillian D.; Hamilton, Carol D.; Stout, Jason E.

    2011-01-01

    Rationale Rifapentine-based regimens for treating latent tuberculosis infection (LTBI) are being considered for future clinical trials, but even if they prove effective, high drug costs may limit their economic viability. Objectives To inform clinical trial design by estimating the potential costs and effectiveness of rifapentine-based regimens for treatment of latent tuberculosis infection (LTBI). Methods We used a Markov model to estimate cost and societal benefits for three regimens for treating LTBI: Isoniazid/rifapentine daily for one month, isoniazid/rifapentine weekly for three months (self-administered and directly-observed), and isoniazid daily for nine months; a strategy of “no treatment” used for comparison. Costs, quality-adjusted life-years gained, and instances of active tuberculosis averted were calculated for all arms. Results Both daily isoniazid/rifapentine for one month and weekly isoniazid/rifapentine for three months were less expensive and more effective than other strategies under a wide variety of clinically plausibly parameter estimates. Daily isoniazid/rifapentine for one month was the least expensive and most effective regimen. Conclusions Daily isoniazid/rifapentine for one month and weekly isoniazid/rifapentine for three months should be studied in a large-scale clinical trial for efficacy. Because both regimens performed well even if their efficacy is somewhat reduced, study designers should consider relaxing non-inferiority boundaries. PMID:21789248

  1. Economical Analysis of Different Clinical Approaches in Pre-Viability Amniorrhexis—A Case Series

    PubMed Central

    Engemise, Samuel; Thompson, Fiona; Davies, William

    2014-01-01

    Prolonged oligohydramnios following extreme preterm prelabour rupture of membranes (EPPROM) is traditionally associated with a high morbidity and mortality to both the mother and the baby. The clinical maternal evaluation and fetal ultrasound assessment may provide important prognostic information for the clinicians and should be taken into account when counselling the patients so as to provide them with enough information to make decision of continuing or interrupting the pregnancy. Current financial constraints on the National Healthcare Service (NHS) resources make it imperative for clinical decision-makers and budgetary planners to make the right decision of continuing or terminating a second trimester pre-viability amniorrhexis for desperate parents. To assess the economic consequences following EPPROM, the risk of infection to both baby and mother, psychological impact on the parents and associated complications and further disability after delivery on this fragile group of patients to the NHS resources. We review the clinical course, outcome, and the challenges to parents and health care professionals on three pregnancies complicated by EPPROM, occurring before 24 weeks’ gestation with a membrane rupture to delivery interval (latent period) of 14 days or more. The anticipated birth of an extremely premature infant poses many challenges for parents and health care professionals. As parents are faced with difficult decisions that can have a long-term impact on the infant, family and country’s resources, it is critical to provide the type of information and support that is needed by them. Taking all these into consideration with the period of ventilation and respiratory assistance in Neonatal Intensive Care Unit (NICU) is essential to provide maximum chances for survival, minimizing the risk for long term sequelae of the neonate and provides the parents enough time to decide on making the right decision with the associated guidance of the healthcare

  2. Economical Analysis of Different Clinical Approaches in Pre-Viability Amniorrhexis-A Case Series.

    PubMed

    Engemise, Samuel; Thompson, Fiona; Davies, William

    2014-01-09

    Prolonged oligohydramnios following extreme preterm prelabour rupture of membranes (EPPROM) is traditionally associated with a high morbidity and mortality to both the mother and the baby. The clinical maternal evaluation and fetal ultrasound assessment may provide important prognostic information for the clinicians and should be taken into account when counselling the patients so as to provide them with enough information to make decision of continuing or interrupting the pregnancy. Current financial constraints on the National Healthcare Service (NHS) resources make it imperative for clinical decision-makers and budgetary planners to make the right decision of continuing or terminating a second trimester pre-viability amniorrhexis for desperate parents. To assess the economic consequences following EPPROM, the risk of infection to both baby and mother, psychological impact on the parents and associated complications and further disability after delivery on this fragile group of patients to the NHS resources. We review the clinical course, outcome, and the challenges to parents and health care professionals on three pregnancies complicated by EPPROM, occurring before 24 weeks' gestation with a membrane rupture to delivery interval (latent period) of 14 days or more. The anticipated birth of an extremely premature infant poses many challenges for parents and health care professionals. As parents are faced with difficult decisions that can have a long-term impact on the infant, family and country's resources, it is critical to provide the type of information and support that is needed by them. Taking all these into consideration with the period of ventilation and respiratory assistance in Neonatal Intensive Care Unit (NICU) is essential to provide maximum chances for survival, minimizing the risk for long term sequelae of the neonate and provides the parents enough time to decide on making the right decision with the associated guidance of the healthcare provider.

  3. Comparison of various techniques for determining viability of Paracoccidioides brasiliensis yeast-form cells.

    PubMed Central

    Restrepo, A; Cano, L E; de Bedout, C; Brummer, E; Stevens, D A

    1982-01-01

    The viability of Paracoccidioides brasiliensis yeast-form cells was determined by colony-forming units, direct fluorescent staining, and production of germ tubes in slide culture. The first procedure was unreliable and time consuming; the latter two showed better correlation with hemacytometer total cell counts and required significantly less time. PMID:7107858

  4. [Methylene blue test for the determination of viability of free larvae of Trichinella spiralis].

    PubMed

    Randazzo, V R; Costamagna, S R

    2010-01-01

    The present research was carried out with the purpose of determining whether or not the methylene blue test could also evidence viability of free larvae of Trichinella spiralis, taking into account its usefulness in the determination of viability of protoscolices in Echinococcus granulosus. To this end, three T. spiralis larval suspensions (M1, M2 and M3) were used, each containing 500 free larval stages. A hundred microl of methylene blue solution 1:10000 in distilled water were added to 100 microl of the larval suspension. Larvae were observed under optical microscopy to evaluate motility. M1 was exposed to -30 degrees C and could be observed on day 70, M2 was exposed to 80 degrees C during 5 minutes and it was immediately observed under optical microscopy, and M3 was maintained at 4 degrees C during the experiment as a 100% viability testing. Our results indicated that when T. spiralis larvae took up 100% of the methylene blue stain (M1 and M2), their inner structures appeared not only retracted but also stained blue, whereas in the M3 suspension test, larvae remained unstained and 100% of them showed their typical spiral-like movement.

  5. Economic viability and critical influencing factors assessment of black water and grey water source-separation sanitation system.

    PubMed

    Thibodeau, C; Monette, F; Glaus, M; Laflamme, C B

    2011-01-01

    The black water and grey water source-separation sanitation system aims at efficient use of energy (biogas), water and nutrients but currently lacks evidence of economic viability to be considered a credible alternative to the conventional system. This study intends to demonstrate economic viability, identify main cost contributors and assess critical influencing factors. A technico-economic model was built based on a new neighbourhood in a Canadian context. Three implementation scales of source-separation system are defined: 500, 5,000 and 50,000 inhabitants. The results show that the source-separation system is 33% to 118% more costly than the conventional system, with the larger cost differential obtained by lower source-separation system implementation scales. A sensitivity analysis demonstrates that vacuum toilet flow reduction from 1.0 to 0.25 L/flush decreases source-separation system cost between 23 and 27%. It also shows that high resource costs can be beneficial or unfavourable to the source-separation system depending on whether the vacuum toilet flow is low or normal. Therefore, the future of this configuration of the source-separation system lies mainly in vacuum toilet flow reduction or the introduction of new efficient effluent volume reduction processes (e.g. reverse osmosis).

  6. A MULTIPLEXED ASSAY FOR DETERMINATION OF NEUROTOXICANT EFFECTS ON SPONTANEOUS NETWORK ACTIVITY AND CELL VIABILITY FROM MICROELECTRODE ARRAYS

    EPA Science Inventory

    AbstractTITLE: A MULTIPLEXED ASSAY FOR DETERMINATION OF NEUROTOXICANT EFFECTS ON SPONTANEOUS NETWORK ACTIVITY AND CELL VIABILITY FROM MICROELECTRODE ARRAYSABSTRACT BODY: Microelectrode array (MEA) recordings are increasingly being used as an in vitro method to detect and characte...

  7. Neoliberalism in a Conflict State: The Viability of Economic Shock Therapy in Iraq

    DTIC Science & Technology

    2004-06-01

    strategy’s success, at least in the near future. If not neoliberalism in its pure form, then what for Iraq.? Dani Rodrik , one of the more perceptive...Literature (September 2003): 885-99 and Dani Rodrik , "Understanding Policy Reform," Journal of Economic Literature (March 1996). 13. Naomi Koppel, "Iraq...1 (Winter 2002), p. 77 44. Sabre Aire Al-Saadi, "Iraq’s Post-War Economy: A Critical Review," Middle East Economic Survey, April 5, 2004. 45. Dani

  8. Assessing the Economic Viability of Bio-based Products for Missouri Value-added Crop Production

    SciTech Connect

    Nicholas Kalaitzandonakes

    2005-11-30

    While research and development on biobased products has continued strong over the years, parallel attention on the economics and management of such product innovation has been lacking. With the financial support of the Department of Energy, the Economics and Management of Agrobiotechnology Center at the University of Missouri-Columbia has launched a pilot graduate education program that seeks to fill the gap. Within this context, a multi-disciplinary research and teaching program has been structured with an emphasis on new product and innovation economics and management. More specifically, this pilot graduate education program has the following major objectives: (1) To provide students with a strong background in innovation economics, management, and strategy. (2) To diversify the students academic background with coursework in science and technology. (3) To familiarize the student with biobased policy initiatives through interaction with state and national level organizations and policymakers. (4) To facilitate active collaboration with industry involved in the development and production of biobased products. The pilot education program seeks to develop human capital and research output. Although the research is, initially, focused on issues related to the State of Missouri, the results are expected to have national implications for the economy, producers, consumers and environment.

  9. The future viability of algae-derived biodiesel under economic and technical uncertainties.

    PubMed

    Brownbridge, George; Azadi, Pooya; Smallbone, Andrew; Bhave, Amit; Taylor, Benjamin; Kraft, Markus

    2014-01-01

    This study presents a techno-economic assessment of algae-derived biodiesel under economic and technical uncertainties associated with the development of algal biorefineries. A global sensitivity analysis was performed using a High Dimensional Model Representation (HDMR) method. It was found that, considering reasonable ranges over which each parameter can vary, the sensitivity of the biodiesel production cost to the key input parameters decreases in the following order: algae oil content>algae annual productivity per unit area>plant production capacity>carbon price increase rate. It was also found that the Return on Investment (ROI) is highly sensitive to the algae oil content, and to a lesser extent to the algae annual productivity, crude oil price and price increase rate, plant production capacity, and carbon price increase rate. For a large scale plant (100,000 tonnes of biodiesel per year) the production cost of biodiesel is likely to be £0.8-1.6 per kg.

  10. Assessment of the efficiency and economic viability of various methods of treatment of sanitary landfill leachate.

    PubMed

    Gupta, S K; Singh, Gurdeep

    2007-12-01

    This study assesses the efficiency of various physico-chemical, biological and other tertiary methods for treating leachate. An evaluation study on the treatability of the leachate from methane phase bed (MPB) reactor indicated that at an optimum hydraulic retention time of 6 days, the efficiency of the reactor in terms of biological oxygen demand (BOD) and chemical oxygen demand (COD) removal was 91.29 and 82.69%, respectively. Recycling of the treated leachate through the municipal solid waste layers in the leachate recycling unit (LRU) resulted in a significant increase in the biodegradation of organics present in the leachate. Optimum BOD and COD removal efficiencies were achieved at the third recycle; additional recycling of the leachate did not produce any significant improvement. Physico-chemical treatment of the leachate demonstrated that alum and lime (Option 2) were more economical than coagulants lime and MgCO(3). A cost analysis of the economics of the various treatments revealed that the alternative treatment consisting of a MPB bed followed by a LRU and aerated lagoon is the most cost-effective treatment. However, the alternative consisting of a MPB followed by the LRU and a soil column, which is slightly more costly, would be the most appropriate treatment when adequate land is readily available.

  11. Acetone-butanol-ethanol fermentation of corn stover: current production methods, economic viability and commercial use.

    PubMed

    Baral, Nawa R; Slutzky, Lauren; Shah, Ajay; Ezeji, Thaddeus C; Cornish, Katrina; Christy, Ann

    2016-03-01

    Biobutanol is a next-generation liquid biofuel with properties akin to those of gasoline. There is a widespread effort to commercialize biobutanol production from agricultural residues, such as corn stover, which do not compete with human and animal foods. This pursuit is backed by extensive government mandates to expand alternative energy sources. This review provides an overview of research on biobutanol production using corn stover feedstock. Structural composition, pretreatment, sugar yield (following pretreatment and hydrolysis) and generation of lignocellulose-derived microbial inhibitory compounds (LDMICs) from corn stover are discussed. The review also discusses different Clostridium species and strains employed for biobutanol production from corn stover-derived sugars with respect to solvent yields, tolerance to LDMICs and in situ solvent recovery (integrated fermentation). Further, the economics of cellulosic biobutanol production are highlighted and compared to corn starch-derived ethanol and gasoline. As discussed herein, the economic competitiveness of biobutanol production from corn stover largely depends on feedstock processing and fermentation process design.

  12. Integrated watershed- and farm-scale modeling framework for targeting critical source areas while maintaining farm economic viability.

    PubMed

    Ghebremichael, Lula T; Veith, Tamie L; Hamlett, James M

    2013-01-15

    environmental mitigation at the farm- and watershed-levels. This paper also outlines steps needed to extract important CSA-related information from a watershed model to help inform targeting decisions at the farm scale. The modeling framework is demonstrated with two unique case studies in the northeastern United States (New York and Vermont), with supporting data from numerous published, location-specific studies at both the watershed and farm scales. Using the integrated modeling framework, it can be possible to compare the costs (in terms of changes required in farm system components or financial compensations for retiring crop lands) and benefits (in terms of measurable water quality improvement goals) of implementing targeted BMPs. This multi-scale modeling approach can be used in the multi-objective task of mitigating CSAs of pollution to meet water quality goals while maintaining farm-level economic viability.

  13. 7 CFR 400.653 - Determining crops of economic significance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Determining crops of economic significance. 400.653... Reform, Insurance Implementation § 400.653 Determining crops of economic significance. To be eligible for... of economic significance if the producer does not execute a waiver of any eligibility for...

  14. 7 CFR 400.653 - Determining crops of economic significance.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Determining crops of economic significance. 400.653... Reform, Insurance Implementation § 400.653 Determining crops of economic significance. To be eligible for... of economic significance if the producer does not execute a waiver of any eligibility for...

  15. 7 CFR 400.653 - Determining crops of economic significance.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Determining crops of economic significance. 400.653... Reform, Insurance Implementation § 400.653 Determining crops of economic significance. To be eligible for... of economic significance if the producer does not execute a waiver of any eligibility for...

  16. 7 CFR 400.653 - Determining crops of economic significance.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Determining crops of economic significance. 400.653... Reform, Insurance Implementation § 400.653 Determining crops of economic significance. To be eligible for... of economic significance if the producer does not execute a waiver of any eligibility for...

  17. 7 CFR 400.653 - Determining crops of economic significance.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Determining crops of economic significance. 400.653... Reform, Insurance Implementation § 400.653 Determining crops of economic significance. To be eligible for... of economic significance if the producer does not execute a waiver of any eligibility for...

  18. Fluorescein diacetate for determination of cell viability in 3D fibroblast-collagen-GAG constructs.

    PubMed

    Powell, Heather M; Armour, Alexis D; Boyce, Steven T

    2011-01-01

    Quantification of cell viability and distribution within engineered tissues currently relies on representative histology, phenotypic assays, and destructive assays of viability. To evaluate uniformity of cell density throughout 3D collagen scaffolds prior to in vivo use, a nondestructive, field assessment of cell viability is advantageous. Here, we describe a field measure of cell viability in lyophilized collagen-glycosaminoglycan (C-GAG) scaffolds in vitro using fluorescein diacetate (FdA). Fibroblast-C-GAG constructs are stained 1 day after cellular inoculation using 0.04 mg/ml FdA followed by exposure to 366 nm UV light. Construct fluorescence quantified using Metamorph image analysis is correlated with inoculation density, MTT values, and histology of corresponding biopsies. Construct fluorescence correlates significantly with inoculation density (p  <  0.001) and MTT values (p  <  0.001) of biopsies collected immediately after FdA staining. No toxicity is detected in the constructs, as measured by MTT assay before and after the FdA assay at different time points; normal in vitro histology is demonstrated for the FdA-exposed constructs. In conclusion, measurement of intracellular fluorescence with FdA allows for the early, comprehensive measurement of cellular distributions and viability in engineered tissue.

  19. Feasibility study for a 10 MM GPY fuel ethanol plant, Brady Hot Springs, Nevada. Volume II. Geothermal resource, agricultural feedstock, markets and economic viability

    SciTech Connect

    Not Available

    1980-09-01

    The issues of the geothermal resource at Brady's Hot Springs are dealt with: the prospective supply of feedstocks to the ethanol plant, the markets for the spent grain by-products of the plant, the storage, handling and transshipment requirements for the feedstocks and by-products from a rail siding facility at Fernley, the probable market for fuel ethanol in the region, and an assessment of the economic viability of the entire undertaking.

  20. Potential minability and economic viability of the Antaramut-Kurtan-Dzoragukh coal field, north-central Armenia; a prefeasibility study

    USGS Publications Warehouse

    Huber, Douglas W.; Pierce, Brenda S.

    2000-01-01

    Russia, is required for auger mining. Although auger-mining coal reserves do exist, the necessary development work will further verify the extent of these reserves and all of the other indicated reserves. The following items are based on the detailed study reported in this publication. Initial investment.?Following an investment of US $85,000 over a 12-month period in mine development drilling and other activities, a decision must be taken regarding further investment in an ongoing mining operation. If the new data support the opening of the surface mine, __________________________ 1Consultant, 6024 Morning Dew Drive, Austin, TX 78749. 2 U.S. Geological Survey, 956 National Center, Reston, VA 20192 1 2 MINABILITY AND ECONOMIC VIABILITY, ANTARAMUT-KURTAN-DZORAGUKH COAL FIELD the $85,000 development cost is amortized over the first 10 years of mine production. If the new data do not support the opening of the mine, the $85,000 is considered a business development expense that may be written off against profits from other operations for income or other tax purposes or simply as a business loss. Total capital required.?The equipment costs will reach a total of $900,500 which will be amortized over a 7-year period to establish estimated coal mining costs. Estimated working capital costs are $300,000, which will be borrowed. Surface mining reserves.?Approximately 840,200 metric tonnes of surface minable coal reserves at 9.3 m3 of overburden per metric tonne of minable coal is indicated. Recovery of the minable coal at 85 percent will yield 714,000 recoverable metric tonnes of marketable as-mined coal. Auger mining reserves.?Auger-mining reserves of 576,000 metric tonnes are indicated. Recoverable auger-mining reserves of 202,000 metric tonnes (at 35-percent recovery) can be expected. Auger-mining production will vary according to the hole size being used, but, in either case, augering is a very profitable addition to the mining oper

  1. [Simultaneous staining with fluorescein diacetate-propidium iodide to determine isolated cochlear outer hair cell viability of guinea pig].

    PubMed

    Yu, Q; Shi, H; Wang, J

    1995-01-01

    A simultaneous double-staining procedure using fluorescein diacetate (FDA) and propidium iodide (PI) is discribed for use in the determination of isolated cochlear outer hair cell viability. With exciter light, viable cells fluoresce bright green, while nonviable cells are bright red. In cell culture and cytotoxicity studies, double-staining with FDA-PI is a accurate method to discriminate between live and nonviable cells.

  2. Measuring the Determinants of Relative Economic Performance of Rural Areas

    ERIC Educational Resources Information Center

    Agarwal, Sheela; Rahman, Sanzidur; Errington, Andrew

    2009-01-01

    This paper examines the determinants of economic performance of 149 English rural Local Authority Districts (LADs). A Three Stage Least Square (3SLS) estimation procedure was employed to jointly determine the influence of a wide range of indicators representing economic, human, cultural and environmental capital, as well as less tangible or…

  3. Determination of Metabolic Viability and Cell Mass Using a Tandem Resazurin/Sulforhodamine B Assay.

    PubMed

    Silva, Filomena S G; Starostina, Irina G; Ivanova, Vilena V; Rizvanov, Albert A; Oliveira, Paulo J; Pereira, Susana P

    2016-05-04

    The identification of rapid, reliable, and highly reproducible biological assays that can be standardized and routinely used in preclinical tests constitutes a promising approach to reducing drug discovery costs and time. This unit details a tandem, rapid, and reliable cell viability method for preliminary screening of chemical compounds. This assay measures metabolic activity and cell mass in the same cell sample using a dual resazurin/sulforhodamine B assay, eliminating the variation associated with cell seeding and excessive manipulations in assays that test different cell samples across plates. The procedure also reduces the amount of cells, test compound, and reagents required, as well as the time expended in conventional tests, thus resulting in a more confident prediction of toxic thresholds for the tested compounds. © 2016 by John Wiley & Sons, Inc.

  4. Strengths and weaknesses in the determination of Saccharomyces cerevisiae cell viability by ATP-based bioluminescence assay.

    PubMed

    Paciello, Lucia; Falco, Francesco Cristino; Landi, Carmine; Parascandola, Palma

    2013-03-05

    Due to its sensitivity and speed of execution, detection of ATP by luciferin-luciferase reaction is a widely spread system to highlight cell viability. The paper describes the methodology followed to successfully run the assay in the presence of yeast cells of two strains of the yeast Saccharomyces cerevisiae, BY4741 and CEN.PK2-1C and emphasizes the importance of correctly determining the contact time between the lysing agent and the yeast cells. Once this was established, luciferin-luciferase reaction was exploited to determine the maximum specific rate of growth, as well as cell viability in a series of routine tests. The results obtained in this preliminary study highlighted that using luciferin-luciferase can imply an over-estimation of maximum specific growth rate with respect to that determined by optical density and/or viable count. On the contrary, the bioluminescence assay gave the possibility to highlight, if employed together with viable count, physiological changes occurring in yeast cells as response to stressful environmental conditions such as those deriving from exposure of yeast cells to high temperature or those depending on the operative conditions applied during fed-batch operations.

  5. Multiple Freezing Points as a Test for Viability of Plant Stems in the Determination of Frost Hardiness 1

    PubMed Central

    McLeester, R. C.; Weiser, C. J.; Hall, T. C.

    1969-01-01

    A technique is presented for a simple, rapid, and reliable means of determining the viability of plant tissue subjected to freezing temperatures. Freezing curves of excised stems of Cornus stolonifera Michx., and several other genera were studied. Tissue temperature was recorded during freezing of plant stem sections. The heat of crystallization deflected the resultant freezing curves at points where tissue froze. Living stem sections of all genera studied revealed 2 freezing points, while dead tissue exhibited only 1. The influence of variables such as moisture content, sample size, thermocouple placement, and cooling rate on freezing curves was analyzed. Stem samples wrapped in moisture-proof film with a thermocouple inserted into the pith were frozen to a predetermined test temperature, thawed, and subjected to a second freezing cycle. The presence or absence of 2 freezing points in the second freezing cycle was used as a criterion for establishing viability. The results were immediately available and identical to results from regrowth tests which took about 20 days. PMID:16657031

  6. Determination of the Viability of Aeromonas hydrophila in Different Types of Water by Flow Cytometry, and Comparison with Classical Methods

    PubMed Central

    Pianetti, Anna; Falcioni, Tania; Bruscolini, Francesca; Sabatini, Luigia; Sisti, Elivio; Papa, Stefano

    2005-01-01

    The presence of Aeromonas spp. in water can represent a risk for human health. Therefore, it is important to know the physiological status of these bacteria and their survival in the environment. We studied the behavior of a strain of Aeromonas hydrophila in river water, spring water, brackish water, mineral water, and chlorinated drinking water, which had different physical and chemical characteristics. The bacterial content was evaluated by spectrophotometric and plate count techniques. Flow cytometric determination of viability was carried out using a dual-staining technique that enabled us to distinguish viable bacteria from damaged and membrane-compromised bacteria. The traditional methods showed that the bacterial content was variable and dependent on the type of water. The results obtained from the plate count analysis correlated with the absorbance data. In contrast, the flow cytometric analysis results did not correlate with the results obtained by traditional methods; in fact, this technique showed that there were viable cells even when the optical density was low or no longer detectable and there was no plate count value. According to our results, flow cytometry is a suitable method for assessing the viability of bacteria in water samples. Furthermore, it permits fast detection of bacteria that are in a viable but nonculturable state, which are not detectable by conventional methods. PMID:16332772

  7. The economic viability of smallholder timber production under expanding açaí palm production in the Amazon Estuary

    USGS Publications Warehouse

    Fortini, Lucas; Douglas R. Carter,

    2015-01-01

    Relatively little attention has been paid to the economic potentials and limitations of tropical timber production and management at smallholder scales, with the most relevant research focusing on community forestry efforts. As a rare tropical example of long-lasting small-scale timber production, in this study we explore the economics of smallholder vertically integrated timber use to better understand the activity in the context of its primary land use alternative in the Amazon Estuary, açaí palm fruit production. We use data from landowner and firm surveys, participatory monitoring of firms, and detailed forest and sawmill operation monitoring to devise financial returns models of smallholder timber micro firms and açaí palm fruit production. We then compare the economics of the two activities to better understand how differences may shape decisions at the small holder scale that impact current land use shifts in the region.

  8. Real-time direct cell concentration and viability determination using a fully automated microfluidic platform for standalone process monitoring.

    PubMed

    Nunes, P S; Kjaerulff, S; Dufva, M; Mogensen, K B

    2015-06-21

    The industrial production of cells has a large unmet need for greater process monitoring, in addition to the standard temperature, pH and oxygen concentration determination. Monitoring the cell health by a vast range of fluorescence cell-based assays can greatly improve the feedback control and thereby ensure optimal cell production, by prolonging the fermentation cycle and increasing the bioreactor output. In this work, we report on the development of a fully automated microfluidic system capable of extracting samples directly from a bioreactor, diluting the sample, staining the cells, and determining the total cell and dead cells concentrations, within a time frame of 10.3 min. The platform consists of custom made stepper motor actuated peristaltic pumps and valves, fluidic interconnections, sample to waste liquid management and image cytometry-based detection. The total concentration of cells is determined by brightfield microscopy, while fluorescence detection is used to detect propidium iodide stained non-viable cells. This method can be incorporated into facilities with bioreactors to monitor the cell concentration and viability during the cultivation process. Here, we demonstrate the microfluidic system performance by monitoring in real time the cell concentration and viability of yeast extracted directly from an in-house made bioreactor. This is the first demonstration of using the Dean drag force, generated due to the implementation of a curved microchannel geometry in conjunction with high flow rates, to promote passive mixing of cell samples and thus homogenization of the diluted cell plug. The autonomous operation of the fluidics furthermore allows implementation of intelligent protocols for administering air bubbles from the bioreactor in the microfluidic system, so that these will be guided away from the imaging region, thereby significantly improving both the robustness of the system and the quality of the data.

  9. [Non-mutagenic non-targeted radiation effects. Determined decrease of cells viability in populations induced by low dose radiation].

    PubMed

    Bychkovskaia, I B

    2013-01-01

    Experimental data obtained from studies on the objects with different organization were analyzed. These data expand the ideas about the phenomenon of "viability determinate decrease in offspring of irradiated cells" discovered in the 1970s. This phenomenon was evaluated according to the standpoint of modern radiobiology. It is postulated that the studied effects, which are associated with the cytoplasmic structures damage and are clearly manifested in mammalian low proliferative tissues, can be significant for humans in connection with the delayed somatic consequences of low dose irradiation, as well as with a more general problem of longevity reduction. Possibility of inheritance ofthese alteration in protozoa asexual reproduction and metazoan sexual reproduction (generation F1) is demonstrated.

  10. The Empirical Determination of Key Skills from an Economic Perspective

    ERIC Educational Resources Information Center

    Van Loo, Jasper B.; Toolsema, Bert

    2005-01-01

    Notwithstanding an impressive research tradition on key skills, no clear statistical criterion exists that is suitable to determine which skills may be considered key skills. This contribution proposes one possible methodology that can be used to identify key skills. Proposing an economic definition of the key skill concept and disentangling the…

  11. System dynamic modelling to assess economic viability and risk trade-offs for ecological restoration in South Africa.

    PubMed

    Crookes, D J; Blignaut, J N; de Wit, M P; Esler, K J; Le Maitre, D C; Milton, S J; Mitchell, S A; Cloete, J; de Abreu, P; Fourie nee Vlok, H; Gull, K; Marx, D; Mugido, W; Ndhlovu, T; Nowell, M; Pauw, M; Rebelo, A

    2013-05-15

    Can markets assist by providing support for ecological restoration, and if so, under what conditions? The first step in addressing this question is to develop a consistent methodology for economic evaluation of ecological restoration projects. A risk analysis process was followed in which a system dynamics model was constructed for eight diverse case study sites where ecological restoration is currently being pursued. Restoration costs vary across each of these sites, as do the benefits associated with restored ecosystem functioning. The system dynamics model simulates the ecological, hydrological and economic benefits of ecological restoration and informs a portfolio mapping exercise where payoffs are matched against the likelihood of success of a project, as well as a number of other factors (such as project costs and risk measures). This is the first known application that couples ecological restoration with system dynamics and portfolio mapping. The results suggest an approach that is able to move beyond traditional indicators of project success, since the effect of discounting is virtually eliminated. We conclude that systems dynamic modelling with portfolio mapping can guide decisions on when markets for restoration activities may be feasible.

  12. Assessment of economic viability of solid waste service provision in small settlements in developing countries: case study Rosetta, Egypt.

    PubMed

    Abdrabo, Mohamed Abdel-Karim

    2008-12-01

    Problems associated with solid waste management (SWM) service provision in developing countries are reaching an ever increasing magnitude, leading to considerable adverse impacts on the environment and quality of life of the inhabitants. Such problems are usually associated with limited managerial, technical and financial capabilities of municipal authorities. Municipal authorities in Egypt that are responsible for SWM services have always been accused of providing a less than satisfactory service, leading to huge quantities of solid waste being uncollected. This study assesses the potential for the provision of an effective and sustainable service, by estimating willingness of the residents to pay for such a service and the cost involved in its provision. The study covered the Rosetta urban centre and its adjacent areas, which are located in the northwestern part of the Nile Delta. It was found that, from an economic perspective, a viable SWM service could be provided in the study area using local funds. In order to increase the likelihood of success of such a service, it may be provided by a local firm or a cooperative to be established for that purpose.

  13. 28 CFR 104.43 - Determination of presumed economic loss for decedents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Determination of presumed economic loss... Determination of presumed economic loss for decedents. In reaching presumed determinations for economic loss for... prior earned income, or who worked only part time outside the home, economic loss may be determined...

  14. Investigation to Determine the Validity and Viability of a Regional Biomedical Equipment Technician Program at the Community College Level. Final Report.

    ERIC Educational Resources Information Center

    Mruk, Walter F.; Fenwick, Douglas E.

    A study was conducted to determine the validity and viability of a Southeastern Pennsylvania biomedical equipment technician program at the community college level. The results of a survey questionnaire, site visits, and interviews with administrators of existing health care facilities and ongoing biomedical curricula, indicated the following: (1)…

  15. Economic viability of phytoremediation of a cadmium contaminated agricultural area using energy maize. Part II: economics of anaerobic digestion of metal contaminated maize in Belgium.

    PubMed

    Thewys, T; Witters, N; Meers, E; Vangronsveld, J

    2010-09-01

    This paper deals with remediation of the Campine soil, an agricultural area diffusely contaminated with metals where most farmers raise dairy cattle and grow fodder maize. In a previous study, we calculated the effect of switching from fodder to energy maize on the farmer's income. Selling this energy maize as feedstock for anaerobic digestion to produce renewable energy could lead to a significant increase in his income. This paper explores the economic opportunities for the farmer of digesting the harvested contaminated biomass himself, by performing a Net Present Value (NPV) analysis on the digestion activity and by calculating the probability of a positive NPV of income resulting from the digestion installation. We investigate the trade off between the maximum price for energy maize that can be paid by the digestion activity and the minimum price that the farming activity needs to compensate for covering its production costs. Integrating the previous study in the current analysis results in an increase of total extra income for the farmer (i.e., from both growing energy maize and performing digestion).

  16. 28 CFR 104.43 - Determination of presumed economic loss for decedents.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Determination of presumed economic loss... of presumed economic loss for decedents. In reaching presumed determinations for economic loss for...-time outside the home, economic loss may be determined with reference to replacement services...

  17. 28 CFR 104.43 - Determination of presumed economic loss for decedents.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Determination of presumed economic loss... of presumed economic loss for decedents. In reaching presumed determinations for economic loss for...-time outside the home, economic loss may be determined with reference to replacement services...

  18. 28 CFR 104.43 - Determination of presumed economic loss for decedents.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Determination of presumed economic loss... of presumed economic loss for decedents. In reaching presumed determinations for economic loss for...-time outside the home, economic loss may be determined with reference to replacement services...

  19. The determinants of dumping: a national study of economically motivated transfers involving mental health care.

    PubMed Central

    Schlesinger, M; Dorwart, R; Hoover, C; Epstein, S

    1997-01-01

    OBJECTIVE: To examine the prevalence and determinants of economically motivated transfers (aka "dumping") from hospitals treating mental illness. DATA SOURCES: A composite data set constructed from three national random-sampled surveys conducted in 1988 and 1989: (1) of hospitals providing mental health care, (2) of community mental health centers, and (3) of psychiatrists. STUDY DESIGN: The study uses reports from administrators of community mental health centers (CMHCs) to assess the extent of patient dumping by hospitals. To assess the determinants of dumping, reported perceptions of dumping are regressed on variables describing the catchment area in terms of the proportion of for-profit hospitals, intensity of competition among hospitals, extent of utilization review, and capacity of the local treatment system, as well as competition among community mental health centers. To assess if dumping is motivated by factors distinct from those affecting other aspects of access, comparable regressions are estimated with ease of hospital admission as the dependent variables. PRINCIPAL FINDINGS: Economically motivated transfers of psychiatric patients were widespread in 1988: according to the reports of CMHC administrators, 64.7 percent of all hospitals providing inpatient mental health care engaged in transfers of this sort. The extent of dumping was higher in catchment areas with more competition among hospitals, more proprietary hospitals, and less inpatient capacity in the public sector. Dumping appeared to be more sensitive to capacity in the public sector but less sensitive to involvement by for-profit hospitals than were other measures of access to care. CONCLUSIONS: Economically motivated transfers of patients with mental illness were widespread in 1988 and likely have increased since that time, affecting the viability of the community mental health care system. PMID:9402901

  20. Dairy goat kids fed liquid diets in substitution of goat milk and slaughtered at different ages: an economic viability analysis using Monte Carlo techniques.

    PubMed

    Knupp, L S; Veloso, C M; Marcondes, M I; Silveira, T S; Silva, A L; Souza, N O; Knupp, S N R; Cannas, A

    2016-03-01

    The aim of this study was to analyze the economic viability of producing dairy goat kids fed liquid diets in alternative of goat milk and slaughtered at two different ages. Forty-eight male newborn Saanen and Alpine kids were selected and allocated to four groups using a completely randomized factorial design: goat milk (GM), cow milk (CM), commercial milk replacer (CMR) and fermented cow colostrum (FC). Each group was then divided into two groups: slaughter at 60 and 90 days of age. The animals received Tifton hay and concentrate ad libitum. The values of total costs of liquid and solid feed plus labor, income and average gross margin were calculated. The data were then analyzed using the Monte Carlo techniques with the @Risk 5.5 software, with 1000 iterations of the variables being studied through the model. The kids fed GM and CMR generated negative profitability values when slaughtered at 60 days (US$ -16.4 and US$ -2.17, respectively) and also at 90 days (US$ -30.8 and US$ -0.18, respectively). The risk analysis showed that there is a 98% probability that profitability would be negative when GM is used. In this regard, CM and FC presented low risk when the kids were slaughtered at 60 days (8.5% and 21.2%, respectively) and an even lower risk when animals were slaughtered at 90 days (5.2% and 3.8%, respectively). The kids fed CM and slaughtered at 90 days presented the highest average gross income (US$ 67.88) and also average gross margin (US$ 18.43/animal). For the 60-day rearing regime to be economically viable, the CMR cost should not exceed 11.47% of the animal-selling price. This implies that the replacer cannot cost more than US$ 0.39 and 0.43/kg for the 60- and 90-day feeding regimes, respectively. The sensitivity analysis showed that the variables with the greatest impact on the final model's results were animal selling price, liquid diet cost, final weight at slaughter and labor. In conclusion, the production of male dairy goat kids can be economically

  1. Emergent Challenges in Determining Costs for Economic Evaluations.

    PubMed

    Jacobs, Josephine C; Barnett, Paul G

    2017-02-01

    This paper describes methods of determining costs for economic evaluations of healthcare and considers how cost determination is being affected by recent developments in healthcare. The literature was reviewed to identify the strengths and weaknesses of the four principal methods of cost determination: micro-costing, activity-based costing, charge-based costing, and gross costing. A scoping review was conducted to identify key trends in healthcare delivery and to identify costing issues associated with these changes. Existing guidelines provide information on how to implement various costing methods. Bottom-up costing is needed when accuracy is paramount, but top-down approaches are often the only feasible approach. We describe six healthcare trends that have important implications for costing methodology: (1) reform in payment mechanisms; (2) care delivery in less restrictive settings; (3) the growth of telehealth interventions; (4) the proliferation of new technology; (5) patient privacy concerns; and (6) growing efforts to implement guidelines. Some costs are difficult to measure and have been overlooked. These include physician services for inpatients, facility costs for outpatient services, the cost of developing treatment innovations, patient and caregiver costs, and the indirect costs of organizational interventions. Standardized methods are needed to determine social welfare and productivity costs. In the future, cost determination will be facilitated by technological advances but hindered by the shift to capitated payment, to the provision of care in less restrictive settings, and by heightened concern for medical record privacy.

  2. 10 CFR 600.503 - Determining the economic interest of the United States.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Determining the economic interest of the United States... Policy § 600.503 Determining the economic interest of the United States. In determining whether participation of an applicant company in a covered program would be in the economic interest of the...

  3. Epidemiological, evolutionary, and economic determinants of eradication tails.

    PubMed

    Mazzucco, Rupert; Dieckmann, Ulf; Metz, Johan A J

    2016-09-21

    Despite modern medical interventions, infectious diseases continue to generate huge socio-economic losses. The benefits of eradicating a disease are therefore high. While successful with smallpox and rinderpest, many other eradication attempts have failed. Eradications require huge and costly efforts, which can be sustained only if sufficient progress can be achieved. While initial successes are usually obtained more easily, progress often becomes harder as a disease becomes rare in the eradication endgame. A long eradication tail of slowly decreasing incidence levels can frustrate eradication efforts, as it becomes unclear whether progress toward eradication is still being made and how much more needs to be invested to push the targeted disease beyond its extinction threshold. Realistic disease dynamics are complicated by evolutionary responses to interventions and by interactions among different temporal and spatial scales. Models accounting for these complexities are required for understanding the shapes of eradication tails. In particular, such models allow predicting how hard or costly eradication will be, and may even inform in which manner progress has to be assessed during the eradication endgame. Here we outline a general procedure by analyzing the eradication tails of generic SIS diseases, taking into account two major ingredients of realistic complexity: a group-structured host population in which host contacts within groups are more likely than host contacts between groups, and virulence evolution subject to a trade-off between host infectivity within groups and host mobility among groups. Disentangling the epidemiological, evolutionary, and economic determinants of eradication tails, we show how tails of different shapes arise depending on salient model parameters and on how the extinction threshold is approached. We find that disease evolution generally extends the eradication tail and show how the cost structure of eradication measures plays a key

  4. Cell viability assays: introduction.

    PubMed

    Stoddart, Martin J

    2011-01-01

    The measurement of cell viability plays a fundamental role in all forms of cell culture. Sometimes it is the main purpose of the experiment, such as in toxicity assays. Alternatively, cell viability can be used to -correlate cell behaviour to cell number, providing a more accurate picture of, for example, anabolic -activity. There are wide arrays of cell viability methods which range from the most routine trypan blue dye exclusion assay to highly complex analysis of individual cells, such as using RAMAN microscopy. The cost, speed, and complexity of equipment required will all play a role in determining the assay used. This chapter aims to provide an overview of many of the assays available today.

  5. 49 CFR 26.67 - What rules determine social and economic disadvantage?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false What rules determine social and economic... Standards § 26.67 What rules determine social and economic disadvantage? (a) Presumption of disadvantage. (1... individual's presumption of economic disadvantage is rebutted. You are not required to have a...

  6. 49 CFR 26.67 - What rules determine social and economic disadvantage?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false What rules determine social and economic... Standards § 26.67 What rules determine social and economic disadvantage? (a) Presumption of disadvantage. (1... individual's presumption of economic disadvantage is rebutted. You are not required to have a...

  7. 41 CFR 101-5.104-2 - Basis for determining economic feasibility.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... economic feasibility. 101-5.104-2 Section 101-5.104-2 Public Contracts and Property Management Federal... SERVICES IN FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-2 Basis for determining economic feasibility. (a) Whenever possible, determination of the economic feasibility of a proposed...

  8. 49 CFR 26.67 - What rules determine social and economic disadvantage?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false What rules determine social and economic... Standards § 26.67 What rules determine social and economic disadvantage? (a) Presumption of disadvantage. (1... individual's presumption of economic disadvantage is rebutted. You are not required to have a...

  9. 41 CFR 101-5.104-2 - Basis for determining economic feasibility.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... economic feasibility. 101-5.104-2 Section 101-5.104-2 Public Contracts and Property Management Federal... SERVICES IN FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-2 Basis for determining economic feasibility. (a) Whenever possible, determination of the economic feasibility of a proposed...

  10. 41 CFR 101-5.104-2 - Basis for determining economic feasibility.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... economic feasibility. 101-5.104-2 Section 101-5.104-2 Public Contracts and Property Management Federal... SERVICES IN FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-2 Basis for determining economic feasibility. (a) Whenever possible, determination of the economic feasibility of a proposed...

  11. 41 CFR 101-5.104-2 - Basis for determining economic feasibility.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... economic feasibility. 101-5.104-2 Section 101-5.104-2 Public Contracts and Property Management Federal... SERVICES IN FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-2 Basis for determining economic feasibility. (a) Whenever possible, determination of the economic feasibility of a proposed...

  12. 49 CFR 26.67 - What rules determine social and economic disadvantage?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false What rules determine social and economic... Standards § 26.67 What rules determine social and economic disadvantage? (a) Presumption of disadvantage. (1... individual's presumption of economic disadvantage is rebutted. You are not required to have a...

  13. Determination of Fares: Pricing Theory and Economic Efficiency

    NASA Technical Reports Server (NTRS)

    Miller, J. C., III

    1972-01-01

    The concept of economic efficiency is described, its application to the pricing of air transport services, and its relevance as a policy objective are outlined. The first two sections discuss economic efficiency in general terms, whereas the third applies this norm to several airline pricing problems. The final section emphasizes the importance of industry behavior as a parameter in policy analysis.

  14. Myocardial viability.

    PubMed Central

    Birnbaum, Y; Kloner, R A

    1996-01-01

    Left ventricular function is a major predictor of outcome in patients with coronary artery disease. Acute ischemia, postischemic dysfunction (stunning), myocardial hibernation, or a combination of these 3 are among the reversible forms of myocardial dysfunction. In myocardial stunning, dysfunction occurs despite normal myocardial perfusion, and function recovers spontaneously over time. In acute ischemia and hibernation, there is regional hypoperfusion. Function improves only after revascularization. Evidence of myocardial viability usually relies on the demonstration of uptake of various metabolic tracers, such as thallium (thallous chloride TI 201) or fludeoxyglucose F 18, by dysfunctional myocardium or by the demonstration of contractile reserve in a dysfunctional region. This can be shown as an augmentation of function during the infusion of various sympathomimetic agents. The response of ventricular segments to increasing doses of dobutamine may indicate the underlying mechanism of dysfunction. Stunned segments that have normal perfusion show dose-dependent augmentation of function. If perfusion is reduced as in hibernating myocardium, however, a biphasic response usually occurs: function improves at low doses of dobutamine, whereas higher doses may induce ischemia and, hence, dysfunction. But in patients with severely impaired perfusion, even low doses may cause ischemia. Myocardial regions with subendocardial infarction or diffuse scarring may also have augmented contractility during catecholamine infusion due to stimulation of the subepicardial layers. In these cases, augmentation of function after revascularization is not expected. Because the underlying mechanism, prognosis, and therapy may differ among these conditions, it is crucial to differentiate among dysfunctional myocardial segments that are nonviable and have no potential to regain function, hibernating or ischemic segments in which recovery of function occurs only after revascularization, and

  15. Using Economics to Determine the Efficient Curtailment of Wind Energy

    SciTech Connect

    Ela, E.

    2009-02-01

    This paper discusses the potential societal benefits to the energy market by allowing the dispatch of wind generation in times when it may enhance reliability and be economically advantageous to do so.

  16. Determination of yeast viability during a stress-model alcoholic fermentation using reagent-free microscopy image analysis.

    PubMed

    Tibayrenc, Pierre; Ghommidh, Charles; Preziosi-Belloy, Laurence

    2011-01-01

    A dedicated microscopy imaging system including automated positioning, focusing, image acquisition, and image analysis was developed to characterize a yeast population with regard to cell morphology. This method was used to monitor a stress-model alcoholic fermentation with Saccharomyces cerevisiae. Combination of dark field and epifluorescence microscopy after propidium iodide staining for membrane integrity showed that cell death went along with important changes in cell morphology, with a cell shrinking, the onset of inhomogeneities in the cytoplasm, and a detachment of the plasma membrane from the cell wall. These modifications were significant enough to enable a trained human operator to make the difference between dead and viable cells. Accordingly, a multivariate data analysis using an artificial neural network was achieved to build a predictive model to infer viability at single-cell level automatically from microscopy images without any staining. Applying this method to in situ microscope images could help to detect abnormal situations during a fermentation course and to prevent cell death by applying adapted corrective actions.

  17. Phospholipase Dα1-mediated phosphatidic acid change is a key determinant of desiccation-induced viability loss in seeds.

    PubMed

    Chen, Hongying; Yu, Xiaomei; Zhang, Xudong; Yang, Lan; Huang, Xing; Zhang, Jie; Pritchard, Hugh W; Li, Weiqi

    2017-02-02

    High sensitivity of seeds to water loss is a widespread phenomenon in the world's plant species. The molecular basis of this trait is poorly understood but thought to be associated with critical changes in membrane function. We profiled membrane lipids of seeds in eight species with varying levels of desiccation tolerance and found a close association between reducing seed viability and increasing phosphatidic acid (PA). We applied hydration-dehydration cycles to Arabidopsis seeds, which are normally desiccation tolerant, to mimic the onset of desiccation sensitivity with progression towards germination and examined the role of phospholipase D (PLD) in desiccation stress-induced production of PA. We found that PLDα1 became more abundant and migrated from the cytosol to the membrane during desiccation, whereas PLDδ did not change, and that all desiccation-induced PA was derived from PLDα1 hydrolysis. When PLDα1 was suppressed, the germination level after each hydration-dehydration cycle improved significantly. We further demonstrated that PLDα1-mediated PA formation modulates desiccation sensitivity as applying its inhibitor improved seed desiccation tolerance and its suppression in protoplasts enhanced survival under dehydration. The insights provided by comparative lipidomics enable us to propose a new membrane-based model for seed desiccation stress and survival.

  18. Use of cardiac magnetic resonance imaging to determine myocardial viability in an infant with in utero septal myocardial infarction and ventricular noncompaction.

    PubMed

    Whitham, Jennifer K E; Hasan, Babar S; Schamberger, Marcus S; Johnson, Tiffanie R

    2008-09-01

    We describe the use of cardiac magnetic resonance imaging (CMRI) to determine myocardial viability and subsequently clinical prognosis in a patient with in utero septal myocardial infarction (MI) and dilated cardiomyopathy. MI is most commonly associated with congenital heart disease. These lesions include aortic atresia and stenosis, interrupted aortic arch, hypoplastic left ventricle (LV), and total anomalous pulmonary venous return (TAPVR). Within the last decade, it has been clearly established that systolic dysfunction is not always a definitive status after MI. In the presence of residual viable myocardium and an adequate myocardial perfusion, contractility might normalize-this process being related to a remarkable prognostic benefit. Until the use of CMRI, myocardial viability has been poorly characterized by other imaging modalities, thus making prognosis difficult to predict. Using myocardial delayed-enhancement CMRI, this patient was shown to have a dilated left ventricle with noncompaction, longitudinal midwall hyperenhancement consistent with nonviable tissue, and severely diminished left ventricular function. In conclusion, CMRI is the only imaging modality that can define anatomy, function, and tissue characterization simultaneously. In the future, CMRI could circumvent the need for more invasive diagnostic procedures in determining the cause and prognosis of patients with dilated cardiomyopathy and myocardial infarction.

  19. Comparative assessment of the cytotoxicity of six anti-inflammatory eyedrops in four cultured ocular surface cell lines, as determined by cell viability scores

    PubMed Central

    Ayaki, Masahiko; Iwasawa, Atsuo; Niwano, Yoshimi

    2012-01-01

    Purpose Anti-inflammatory eyedrops are often used in the treatment of corneal epithelial disorders. In the present study, we evaluated the cytotoxicity of six anti-inflammatory eyedrops in four ocular surface cell lines. Methods The cytotoxicity of six commercially available anti-inflammatory ophthalmic solutions (ie, diclofenac, bromfenac, pranoprofen, betamethasone, and fluoromethorone) was assessed in three corneal cell lines and one conjunctival cell line. Cell viability was determined by the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide and neutral red assays after exposing the cells to 10, 30, and 60 minutes of onefold, twofold, and tenfold dilutions of the drugs. Cytotoxicity was compared using the cell viability score (CVS), an integrated cytotoxic parameter that takes various factors into account, such as dilution by tear fluid or concentration by evaporation, drug exposure time, and ocular surface cell type. Results Based on the CVS scores, the order of the anti-inflammatory eyedrops tested from least to most cytotoxic, with the active ingredient %CVS50, and %CVS40/80 for each solution given in parentheses, was as follows: Rinderon® (betamethasone, 100%, 100%) >0.02% Flumethoron® (fluoromethorone, 68%, 22%) = 0.1% Flumethoron® (fluoromethorone, 76%, 22%) >Bronuck® (0.1% bromfenac, 53%, −8%) = Diclod® (0.1% diclofenac, 44%, −15%) = Niflan® (pranoprofen, 50%, −19%). Rinderon® exhibited the least toxicity of all the anti-inflammatory eyedrops tested. Eyedrops containing non-steroidal anti-inflammatory drugs exhibited greater cytotoxicity than those containing steroids with benzalkonium at comparable concentrations. Concentration was the most significant factor affecting cell viability. Conclusion The cytotoxicity of the anti-inflammatory eyedrops evaluated in the present study depended on both the pharmaceutical components and preservatives. The CVS is a concise indicator of drug cytotoxicity. PMID:23185116

  20. Determination of pyruvate and lactate as potential biomarkers of embryo viability in assisted reproduction by capillary electrophoresis with contactless conductivity detection.

    PubMed

    Mádr, Aleš; Celá, Andrea; Klejdus, Bořivoj; Pelcová, Marta; Crha, Igor; Žáková, Jana; Glatz, Zdeněk

    2015-06-01

    Human-assisted reproduction is increasing in importance due to the constantly rising number of couples suffering from infertility issue. A key step in in vitro fertilization is the proper assessment of embryo viability in order to select the embryo with the highest likelihood of resulting in a pregnancy. This study proposes a method based on CE with contactless conductivity detection for the determination of pyruvate and lactate in spent culture media used in human-assisted reproduction. A fused-silica capillary of 64.0 cm total length and 50 μm inner diameter was used. The inner capillary wall was modified by the coating of successive layers of the ionic polymers polybrene and dextran sulfate to reverse EOF. The BGE was composed of 10 mM MES/lithium hydroxide, pH 6.50. The sample was injected by pressure 50 mbar for 18 s, separation voltage was set to -24 kV, and capillary temperature to 15°C. The presented method requires only 2 μL of the culture medium, with LODs for pyruvate and lactate of 0.03 and 0.02 μM, respectively. The results demonstrated the method's suitability for the analysis of spent culture media to support embryo viability assessment by light microscopy, providing information about key metabolites of the energy metabolism of a developing embryo.

  1. 49 CFR Appendix E to Part 26 - Individual Determinations of Social and Economic Disadvantage

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Individual Determinations of Social and Economic... Appendix E to Part 26—Individual Determinations of Social and Economic Disadvantage The following guidance is adapted, with minor modifications, from SBA regulations concerning social and...

  2. 49 CFR Appendix E to Part 26 - Individual Determinations of Social and Economic Disadvantage

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Individual Determinations of Social and Economic... Appendix E to Part 26—Individual Determinations of Social and Economic Disadvantage The following guidance is adapted, with minor modifications, from SBA regulations concerning social and...

  3. 49 CFR Appendix E to Part 26 - Individual Determinations of Social and Economic Disadvantage

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Individual Determinations of Social and Economic... Appendix E to Part 26—Individual Determinations of Social and Economic Disadvantage The following guidance is adapted, with minor modifications, from SBA regulations concerning social and...

  4. 49 CFR Appendix E to Part 26 - Individual Determinations of Social and Economic Disadvantage

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Individual Determinations of Social and Economic... Appendix E to Part 26—Individual Determinations of Social and Economic Disadvantage The following guidance is adapted, with minor modifications, from SBA regulations concerning social and...

  5. 49 CFR Appendix E to Part 26 - Individual Determinations of Social and Economic Disadvantage

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Individual Determinations of Social and Economic... Appendix E to Part 26—Individual Determinations of Social and Economic Disadvantage The following guidance is adapted, with minor modifications, from SBA regulations concerning social and...

  6. The Determinants of Child Health in Pakistan: An Economic Analysis

    ERIC Educational Resources Information Center

    Shehzad, Shafqat

    2006-01-01

    This paper estimates linear structural models using LISREL and employs MIMIC models to find out factors determining child health in Pakistan. A distinction has been made in permanent and transitory health states that lend support to Grossman's (1972) stock and flow concepts of health. The paper addresses the issue of health unobservability and…

  7. Economics.

    PubMed

    Palley, Paul D; Parcero, Miriam E

    2016-10-01

    A review of literature in the calendar year 2015 dedicated to environmental policies and sustainable development, and economic policies. This review is divided into these sections: sustainable development, irrigation, ecosystems and water management, climate change and disaster risk management, economic growth, water supply policies, water consumption, water price regulation, and water price valuation.

  8. Economics.

    ERIC Educational Resources Information Center

    James, L. D.

    1978-01-01

    Presents a literature review of the economic aspects of water pollution control covering publications of 1976-77. This review also includes the policy issues of water management. A list of 77 references is presented. (HM)

  9. Economics.

    ERIC Educational Resources Information Center

    Kemp, Rodger

    This course presents basic economic concepts and explores issues such as how goods and services are produced and distributed, what affects costs and profits, and how wealth is spread around or concentrated. The course is designed to be used with students enrolled in an adult high school diploma program; course content is appropriate to meet social…

  10. An approach to determining the economic feasibility of refuse-derived fuels and materials recovery processing

    SciTech Connect

    Gershman, H.W.

    1980-06-01

    An approach for determining the economic feasibility of refuse-derived fuel production and the recovery of various materials is demonstrated, using data developed for the metropolitan Washington, D.C., area as input. The processing facility, designed to handle 650 tpd of refuse, is described. Since materials revenues can be predicted with a higher degree of certainty than refuse fuel revenues, it is necessary to determine what revenues the sale of solid waste fuel will have to generate for projected economics to be the same as an alternative disposal practice. (1 diagram, 8 references, 6 tables)

  11. Green analytical chemistry introduction to chloropropanols determination at no economic and analytical performance costs?

    PubMed

    Jędrkiewicz, Renata; Orłowski, Aleksander; Namieśnik, Jacek; Tobiszewski, Marek

    2016-01-15

    In this study we perform ranking of analytical procedures for 3-monochloropropane-1,2-diol determination in soy sauces by PROMETHEE method. Multicriteria decision analysis was performed for three different scenarios - metrological, economic and environmental, by application of different weights to decision making criteria. All three scenarios indicate capillary electrophoresis-based procedure as the most preferable. Apart from that the details of ranking results differ for these three scenarios. The second run of rankings was done for scenarios that include metrological, economic and environmental criteria only, neglecting others. These results show that green analytical chemistry-based selection correlates with economic, while there is no correlation with metrological ones. This is an implication that green analytical chemistry can be brought into laboratories without analytical performance costs and it is even supported by economic reasons.

  12. Socio-economic determinants of life expectancy in Nigeria (1980 - 2011).

    PubMed

    Sede, Peter I; Ohemeng, Williams

    2015-01-01

    Attainment of 70 years life expectancy by 2020 is one of the millennium development goals in Nigeria. This study examined the socio-economic determinants of life expectancy in Nigeria using data from 1980-2011. Judging from the endogeneity feature of the variables, A VAR and VECM frameworks were employed. Socio-economic features were proxy by secondary school enrolment, government expenditure on health, per capita income, unemployment rate and the Naira foreign exchange rate. It was found that, the conventional socio-economic variables such as per capita income, education and government expenditure on health considered to be highly effective in determining life expectancy of developing countries are not significant in the case of Nigeria. The study however suggests that, life expectancy in Nigeria could be improved if attention is given to quality of government health expenditure, unemployment and measures to halt the depreciation of the Nigerian Naira against major foreign currency.

  13. 28 CFR 104.45 - Determination of presumed economic loss for claimants who suffered physical harm.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Determination of presumed economic loss for claimants who suffered physical harm. 104.45 Section 104.45 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) SEPTEMBER 11TH VICTIM COMPENSATION FUND OF 2001 Amount of Compensation for...

  14. The impact and determinants of the energy paradigm on economic growth in European Union.

    PubMed

    Andrei, Jean Vasile; Mieila, Mihai; Panait, Mirela

    2017-01-01

    Contemporary economies are strongly reliant on energy and analyzing the determining factors that trigger the changes in energy paradigm and their impact upon economic growth is a topical research subject. Our contention is that energy paradigm plays a major role in achieving the sustainable development of contemporary economies. In order to prove this the panel data methodology of research was employed, namely four panel unit root tests (LLC, IPS, F-ADF and F-PP) aiming to reveal the connections and relevance among 17 variables denoting energy influence on economic development. Moreover, it was introduced a specific indicator to express energy consumption per capita. Our findings extend the classical approach of the changes in energy paradigm and their impact upon economic growth and offer a comprehensive analysis which surpasses the practices and policy decisions in the field.

  15. The impact and determinants of the energy paradigm on economic growth in European Union

    PubMed Central

    Mieila, Mihai; Panait, Mirela

    2017-01-01

    Contemporary economies are strongly reliant on energy and analyzing the determining factors that trigger the changes in energy paradigm and their impact upon economic growth is a topical research subject. Our contention is that energy paradigm plays a major role in achieving the sustainable development of contemporary economies. In order to prove this the panel data methodology of research was employed, namely four panel unit root tests (LLC, IPS, F-ADF and F-PP) aiming to reveal the connections and relevance among 17 variables denoting energy influence on economic development. Moreover, it was introduced a specific indicator to express energy consumption per capita. Our findings extend the classical approach of the changes in energy paradigm and their impact upon economic growth and offer a comprehensive analysis which surpasses the practices and policy decisions in the field. PMID:28301505

  16. Non-Economic Determinants of Energy Use in Rural Areas of South Africa

    SciTech Connect

    Annecke, W.

    1999-03-29

    This project will begin to determine the forces and dimensions in rural energy-use patterns and begin to address policy and implementation needs for the future. This entails: Forecasting the social and economic benefits that electrification is assumed to deliver regarding education and women's lives; Assessing negative perceptions of users, which have been established through the slow uptake of electricity; Making recommendations as to how these perceptions could be addressed in policy development and in the continuing electrification program; Making recommendations to policy makers on how to support and make optimal use of current energy-use practices where these are socio-economically sound; Identifying misinformation and wasteful practices; and Other recommendations, which will significantly improve the success of the rural electrification program in a socio-economically sound manner, as identified in the course of the work.

  17. An approach to determining the economic feasibility of refuse-derived fuel and materials recovery processing

    NASA Astrophysics Data System (ADS)

    Gershman, H. W.

    1980-06-01

    An approach for determining the economic feasibility of refuse-derived fuel production and the recovery of materials is presented. This information is based on data developed for the metropolitan Washington, D.C. area as input for the consideration of a regional resource recovery program which would eventually encompass 4000 t/day of municipal solid waste; it is designed to recover refuse-derived fuel (RDF), ferrous and nonferrous metals, flint and color-mixed glass cullet, color-mixed glass fines, and waste newspapers. The planning process requires estimates of recovery product revenues and of process feasibility; since materials revenues can be predicted with a greater degree of certainty than RDF revenues, it becomes necessary to determine what revenues will be required from the sale of RDF so that predicted economics can be the same as the alternative disposal practice. A technique is described which will assist the decisionmaker in evaluating the economic feasibility of the proposed project by determining the RDF 'Indifference Value'.

  18. Financial and economic determinants of collective action: The case of wastewater management

    SciTech Connect

    Brunner, Norbert; Starkl, Markus

    2012-01-15

    Where public environmental funds support development of wastewater infrastructure, funding institutions ensure the economic use of funds, while the beneficiaries minimize their own costs. In rural areas, there is often a choice between decentralized or centralized (multi-village) systems: if the centralized system is most economic, then only this system is eligible for public funding. However, its implementation requires a voluntary cooperation of the concerned communities, who need to organize themselves to develop and run the infrastructure. The paper analyzes the social determinants of collaboration in a generic case study, using the following variables: method of (economic) assessment, modeled by the social discount rate, funding policy, modeled by the funding rate, and users' self-organization, modeled by cost sharing. In a borderline situation, where the centralized system turns out to be most economic, but this assessment is contingent on the assessment method, collective action may fail: the advantages of collective action from funding are too small to outweigh organizational deficiencies. Considering in this situation sanitation as a human right, authors recommend using innovative forms of organization and, if these fail, reassessing either the amount of funding or the eligibility for funding of more acceptable alternatives. - Highlights: Black-Right-Pointing-Pointer A generic case study models collective action and funding in wastewater management. Black-Right-Pointing-Pointer Determinants of success: economic assessment, funding policy and self-organization. Black-Right-Pointing-Pointer Success indicators: conflict rate, funds needed to make cost shares fair. Black-Right-Pointing-Pointer Method for analyzing centralized vs. decentralized disputes. Black-Right-Pointing-Pointer If collective action has less benefits, innovative cost sharing may ensure success.

  19. A novel dataset on legal traditions, their determinants, and their economic role in 155 transplants.

    PubMed

    Guerriero, Carmine

    2016-09-01

    The law and the economy are deeply influenced by the legal tradition or origin, which is the bundle of institutions shaping lawmaking and dispute adjudication. The two principal legal traditions, common law and civil law, have been transplanted through colonization and occupation to the vast majority of the jurisdictions in the world by a group of European countries. Here, I illustrate a novel dataset recording the lawmaking institution employed by 155 of these jurisdictions at independence and in 2000 and four discretion-curbing adjudication institutions adopted by 99 of these "transplants" at the same two points in time. Contrary to the "legal origins" scholars׳ assumption, 25 transplants changed the transplanted lawmaking institution and 95 modified at least one of the transplanted lawmaking and adjudication rules. In "Endogenous Legal Traditions" (Guerriero, 2016a) [12], I document that these reforms are consistent with a model of the design of legal institutions by societies heterogeneous in their endowment of both the extent of cultural heterogeneity and the quality of the political process. In "Endogenous Legal Traditions and Economic Outcomes" (Guerriero, 2016b) [13] moreover, I show the relevance of considering legal evolution and the endogeneity between legal traditions and economics outcomes. The data illustrated here also include the proxies for the determinants of legal evolution I use in "Endogenous Legal Traditions" (Guerriero, 2016a) [12] and the novel measure of economic outcomes I employ in "Endogenous Legal Traditions and Economic Outcomes" (Guerriero, 2016b) [13].

  20. Recovery and viability of Dirofilaria immitis microfilariae.

    PubMed

    Grieve, R B; Mika-Grieve, M; Lok, J B; Marchell, T F; Cupp, E W

    1984-09-01

    The viability of Dirofilaria immitis microfilariae recovered from canine blood by different methods was determined. Microfilaria recovery techniques included saponin lysis, saponin lysis with a trypsin treatment, dextran sedimentation and phytohemagglutinin treatment. Criteria for evaluating viability were microfilarial motility in vitro at 37 degrees C, microfilarial development in mosquitoes and the ability of microfilariae to circulate in mice. Although each method produced motile microfilariae, differences among groups of microfilariae recovered by different techniques were apparent by each of the criteria for viability. Saponin lysis gave superior yields of viable microfilariae.

  1. Automated Decisional Model for Optimum Economic Order Quantity Determination Using Price Regressive Rates

    NASA Astrophysics Data System (ADS)

    Roşu, M. M.; Tarbă, C. I.; Neagu, C.

    2016-11-01

    The current models for inventory management are complementary, but together they offer a large pallet of elements for solving complex problems of companies when wanting to establish the optimum economic order quantity for unfinished products, row of materials, goods etc. The main objective of this paper is to elaborate an automated decisional model for the calculus of the economic order quantity taking into account the price regressive rates for the total order quantity. This model has two main objectives: first, to determine the periodicity when to be done the order n or the quantity order q; second, to determine the levels of stock: lighting control, security stock etc. In this way we can provide the answer to two fundamental questions: How much must be ordered? When to Order? In the current practice, the business relationships with its suppliers are based on regressive rates for price. This means that suppliers may grant discounts, from a certain level of quantities ordered. Thus, the unit price of the products is a variable which depends on the order size. So, the most important element for choosing the optimum for the economic order quantity is the total cost for ordering and this cost depends on the following elements: the medium price per units, the stock cost, the ordering cost etc.

  2. Union formation in later life: economic determinants of cohabitation and remarriage among older adults.

    PubMed

    Vespa, Jonathan

    2012-08-01

    This study builds on Becker's and Oppenheimer's theories of union formation to examine the economic determinants of marriage and cohabitation during older adulthood. Based on the 1998-2006 Health and Retirement Study and a sample of previously married Americans who are at least 50 years old, results show that wealthier older adults, regardless of gender, are more likely to repartner than stay single. Wealth has no discernable effect on the likelihood of remarrying versus cohabiting. Among the oldest men, the positive associations between wealth and repartnering are entirely due to housing assets. Results suggest that Oppenheimer's theory of marriage timing may be more applicable to later-life union formation than Becker's independence hypothesis. Further, economic disadvantage does not appear to characterize later-life cohabitation, unlike cohabitation during young adulthood. These findings help illuminate the union formation process during older adulthood and are timely considering demographic changes reshaping the American population.

  3. Determinants of Childhood Immunization Uptake among Socio-Economically Disadvantaged Migrants in East China

    PubMed Central

    Hu, Yu; Li, Qian; Chen, Enfu; Chen, Yaping; Qi, Xiaohua

    2013-01-01

    Objective: To determine the coverage of childhood immunization appropriate for age among socio-economically disadvantaged recent migrants living in East China and to identify the determinants of full immunization uptake among these migrant children. Methods: This is a cross-sectional survey of 1,426 migrant mothers with a child aged ≤24 months, who were interviewed with a pretested questionnaire. Various vaccines, migration history and some other social-demographic and income details were collected. Single-level logistic regression analyses were applied to identify the determinants of full immunization status. Results: Immunization coverage rates are lower among migrants and even lower among recent migrants. The likelihood of a child receiving full immunization rise with parents’ educational level and the frequency of mother’s utilization of health care. Higher household income also significantly increase the likelihood of full immunization, as dose post-natal visits by a health worker. Conclusions: Recent migrant status favours low immunization uptake, particularly in the vulnerability context of alienation and livelihood insecurity. Services must be delivered with a focus on recent migrants. Investments are needed in education, socio-economic development and secure livelihoods to improve and sustain equitable health care services. PMID:23839061

  4. Analysis of economic determinants of fertility in Iran: a multilevel approach

    PubMed Central

    Moeeni, Maryam; Pourreza, Abolghasem; Torabi, Fatemeh; Heydari, Hassan; Mahmoudi, Mahmood

    2014-01-01

    Background: During the last three decades, the Total Fertility Rate (TFR) in Iran has fallen considerably; from 6.5 per woman in 1983 to 1.89 in 2010. This paper analyzes the extent to which economic determinants at the micro and macro levels are associated with the number of children in Iranian households. Methods: Household data from the 2010 Household Expenditure and Income Survey (HEIS) is linked to provincial data from the 2010 Iran Multiple-Indicator Demographic and Health Survey (IrMIDHS), the National Census of Population and Housing conducted in 1986, 1996, 2006 and 2011, and the 1985–2010 Iran statistical year books. Fertility is measured as the number of children in each household. A random intercept multilevel Poisson regression function is specified based on a collective model of intra-household bargaining power to investigate potential determinants of the number of children in Iranian households. Results: Ceteris paribus (other things being equal), probability of having more children drops significantly as either real per capita educational expenditure or real total expenditure of each household increase. Both the low- and the high-income households show probabilities of having more children compared to the middle-income households. Living in provinces with either higher average amount of value added of manufacturing establishments or lower average rate of house rent is associated to higher probability of having larger number of children. Higher levels of gender gap indices, resulting in household’s wife’s limited power over household decision-making, positively affect the probability of having more children. Conclusion: Economic determinants at the micro and macro levels, distribution of intra-household bargaining power between spouses and demographic covariates determined fertility behavior of Iranian households. PMID:25197678

  5. Socio-Economic Determinants of the Need for Dental Care in Adults

    PubMed Central

    Trohel, Gilda; Bertaud-Gounot, Valérie; Soler, Marion; Chauvin, Pierre; Grimaud, Olivier

    2016-01-01

    Background Oral health has improved in France. However, there are still inequalities related to the socio-economic status. Objectives The aim of this study was to measure the prevalence of dental care needs in an adult population and to identify the demographic, socio-economic and behavioral variables that may explain variations in this parameter. Methods A cross-sectional analysis of the French SIRS cohort (n = 2,997 adults from the Paris region; 2010 data) was carried out to determine the prevalence of self-reported dental care needs relative to demographic, socio-economic and behavioral variables. A logistic regression model was used to identify the variables that were most strongly associated with the level of need. Results In 2010, the prevalence of the need for dental care in the SIRS cohort was 35.0% (95% CI [32.3–37.8]). It was lower in people with higher education levels (31.3% [27.9–34.6]), without immigrant background (31.3% [28.0–34.6]) and with comprehensive health insurance (social security + complementary health cover; 32.8% [30.2–35.4]). It decreased as the socio-economic status increased, but without following a strict linear change. It was also lower among individuals who had a dental check-up visit in the previous two years. In multivariate analyses, the socioeconomic variables most strongly associated with the need for dental care were: educational attainment (OR = 1.21 [1.02–1.44]), income level (OR = 1.66 [1.92–2.12]) and national origin (OR = 1.53 [1.26–1.86]). Conclusion These results confirm that the prevalence of dental care needs is higher among adults with low socio-economic status. Education level, income level and also national origin were more strongly associated with the need for dental care than insurance cover level. PMID:27441841

  6. Cartilage viability after trochleoplasty.

    PubMed

    Schöttle, Philip B; Schell, Hanna; Duda, Georg; Weiler, Andreas

    2007-02-01

    Trochleoplasty is an established and accepted technique for the treatment of patellar instability because of a missing trochlear groove. In this technique, a flap of cartilage over the trochlea is carefully removed and a new trochlear groove is created in the underlying bone before the cartilaginous flap is reattached with sutures. The mid-term clinical and radiological results of this operation are promising but no information about the viability of the reattached cartilage has been reported. To evaluate cartilage viability and quality after trochleoplasty and to verify the healing process, two osteochondral biopsies were harvested from three patients 6, 8, and 9 months after trochleoplasty. One cylinder was evaluated histologically to assess cartilage, calcified cartilage (cc), and subchondral bone quality, while the other one was examined by confocal microscopy to evaluate cell viability. The histological examination showed a normal matrix and cell distribution of the cartilage, while the cc showed lacunae ingrowing from the underlying bone. The subchondral bone showed normal lamellae and histology, and the healing of the flap. Confocal microscopy showed almost exclusively viable chondrocytes. This demonstration of non-injured cartilage at short-term follow-up together with promising clinical and radiological 2- and 5-year follow-up results indicate a potential promising outlook for the long term, as further chondral damage is not expected. So trochleoplasty can be seen as a primary intervention for patellar instability because of trochlear dysplasia as the risk for cartilage damage is low.

  7. Integration of multiple determinants in the neuronal computation of economic values.

    PubMed

    Raghuraman, Anantha P; Padoa-Schioppa, Camillo

    2014-08-27

    Economic goods may vary on multiple dimensions (determinants). A central conjecture in decision neuroscience is that choices between goods are made by comparing subjective values computed through the integration of all relevant determinants. Previous work identified three groups of neurons in the orbitofrontal cortex (OFC) of monkeys engaged in economic choices: (1) offer value cells, which encode the value of individual offers; (2) chosen value cells, which encode the value of the chosen good; and (3) chosen juice cells, which encode the identity of the chosen good. In principle, these populations could be sufficient to generate a decision. Critically, previous work did not assess whether offer value cells (the putative input to the decision) indeed encode subjective values as opposed to physical properties of the goods, and/or whether offer value cells integrate multiple determinants. To address these issues, we recorded from the OFC while monkeys chose between risky outcomes. Confirming previous observations, three populations of neurons encoded the value of individual offers, the value of the chosen option, and the value-independent choice outcome. The activity of both offer value cells and chosen value cells encoded values defined by the integration of juice quantity and probability. Furthermore, both populations reflected the subjective risk attitude of the animals. We also found additional groups of neurons encoding the risk associated with a particular option, the risky nature of the chosen option, and whether the trial outcome was positive or negative. These results provide substantial support for the conjecture described above and for the involvement of OFC in good-based decisions.

  8. Prevalence, Causes and Socio-Economic Determinants of Vision Loss in Cape Town, South Africa

    PubMed Central

    Cockburn, Nicky; Steven, David; Lecuona, Karin; Joubert, Francois; Rogers, Graeme; Cook, Colin; Polack, Sarah

    2012-01-01

    Purpose To estimate the prevalence and causes of blindness and visual impairment in Cape Town, South Africa and to explore socio-economic and demographic predictors of vision loss in this setting. Methods A cross sectional population-based survey was conducted in Cape Town. Eighty-two clusters were selected using probability proportionate to size sampling. Within each cluster 35 or 40 people aged 50 years and above were selected using compact segment sampling. Visual acuity of participants was assessed and eyes with a visual acuity less than 6/18 were examined by an ophthalmologist to determine the cause of vision loss. Demographic data (age, gender and education) were collected and a socio-economic status (SES) index was created using principal components analysis. Results Out of 3100 eligible people, 2750 (89%) were examined. The sample prevalence of bilateral blindness (presenting visual acuity <3/60) was 1.4% (95% CI 0.9–1.8). Posterior segment diseases accounted for 65% of blindness and cataract was responsible for 27%. The prevalence of vision loss was highest among people over 80 years (odds ratio (OR) 6.9 95% CI 4.6–10.6), those in the poorest SES group (OR 3.9 95% CI 2.2–6.7) and people with no formal education (OR 5.4 95% CI 1.7–16.6). Cataract surgical coverage was 68% in the poorest SES tertile (68%) compared to 93% in the medium and 100% in the highest tertile. Conclusions The prevalence of blindness among people ≥50 years in Cape Town was lower than expected and the contribution of posterior segment diseases higher than previously reported in South Africa and Sub Saharan Africa. There were clear socio-economic disparities in prevalence of vision loss and cataract surgical coverage in this setting which need to be addressed in blindness prevention programs. PMID:22363476

  9. Determinants of biosecurity behaviour of British cattle and sheep farmers-a behavioural economics analysis.

    PubMed

    Toma, Luiza; Stott, Alistair W; Heffernan, Claire; Ringrose, Siân; Gunn, George J

    2013-03-01

    The paper analyses the impact of a priori determinants of biosecurity behaviour of farmers in Great Britain. We use a dataset collected through a stratified telephone survey of 900 cattle and sheep farmers in Great Britain (400 in England and a further 250 in Wales and Scotland respectively) which took place between 25 March 2010 and 18 June 2010. The survey was stratified by farm type, farm size and region. To test the influence of a priori determinants on biosecurity behaviour we used a behavioural economics method, structural equation modelling (SEM) with observed and latent variables. SEM is a statistical technique for testing and estimating causal relationships amongst variables, some of which may be latent using a combination of statistical data and qualitative causal assumptions. Thirteen latent variables were identified and extracted, expressing the behaviour and the underlying determining factors. The variables were: experience, economic factors, organic certification of farm, membership in a cattle/sheep health scheme, perceived usefulness of biosecurity information sources, knowledge about biosecurity measures, perceived importance of specific biosecurity strategies, perceived effect (on farm business in the past five years) of welfare/health regulation, perceived effect of severe outbreaks of animal diseases, attitudes towards livestock biosecurity, attitudes towards animal welfare, influence on decision to apply biosecurity measures and biosecurity behaviour. The SEM model applied on the Great Britain sample has an adequate fit according to the measures of absolute, incremental and parsimonious fit. The results suggest that farmers' perceived importance of specific biosecurity strategies, organic certification of farm, knowledge about biosecurity measures, attitudes towards animal welfare, perceived usefulness of biosecurity information sources, perceived effect on business during the past five years of severe outbreaks of animal diseases, membership

  10. The ScanTrainer obstetrics and gynaecology ultrasound virtual reality training simulator: A cost model to determine the cost viability of replacing clinical training with simulation training

    PubMed Central

    Ray, AF

    2015-01-01

    The aim of this study was to produce an economic cost model comparing the use of the Medaphor ScanTrainer virtual reality training simulator for obstetrics and gynaecology ultrasound to achieve basic competence, with the traditional training method. A literature search and survey of expert opinion were used to identify resources used in training. An executable model was produced in Excel. The model showed a cost saving for a clinic using the ScanTrainer of £7114 per annum. The uncertainties of the model were explored and it was found to be robust. Threshold values for the key drivers of the model were identified. Using the ScanTrainer is cost saving for clinics with at least two trainees per year to train, if it would take at least six lists to train them using the traditional training method and if a traditional training list has at least two fewer patients than a standard list. PMID:27433245

  11. Electrochemical sensing of hepatocyte viability.

    PubMed

    Tsai, Hweiyan; Tsai, Shang-heng; Ting, Wei-Jen; Hu, Chao-Chin; Fuh, C Bor

    2014-05-21

    We investigated the use of amperometric and chronoamperometric methods with a double mediator system and screen-printed electrodes (SPEs) for the electrochemical sensing of hepatocyte viability. Cell counts were determined based on measuring cellular respiration via interaction of electroactive redox mediators. The oxidation currents of chronoamperometric measurement were proportional to the concentrations of ferrocyanide which was produced via interaction of cellular respiration, succinate and ferricyanide. The integrated oxidation charges increased linearly with the density of the cultured primary rat hepatocytes over a range of 1 × 10(5) to 5 × 10(5) cells per well (slope = 1.98 (±0.08) μC per 10(5) cells; R(2) = 0.9969), and the detection limit was 7600 (±300) cells per well based on S/N = 3. Each density of cells was cultured in triple replicates and individual cell samples were evaluated. The results of the cytotoxic effect of the chronoamperometric method are comparable to those of the tetrazolium-based colorimetric assay. The chronoamperometric method with ferricyanide and succinate mediators is an efficient, alternative method for assessing the viability of primary hepatocytes which can be completed in 20 min. Succinate did not provide an efficient electron shuttle between cytosolic respiratory redox activity of cancer cells and extracellular ferricyanide, an effect that may be useful for distinguishing hepatocarcinoma cells from healthy hepatocytes.

  12. Establishing lunar resource viability

    NASA Astrophysics Data System (ADS)

    Carpenter, J.; Fisackerly, R.; Houdou, B.

    2016-11-01

    Recent research has highlighted the potential of lunar resources as an important element of space exploration but their viability has not been demonstrated. Establishing whether or not they can be considered in future plans is a multidisciplinary effort, requiring scientific expertise and delivering scientific results. To this end various space agencies and private entities are looking to lunar resources, extracted and processed in situ, as a potentially game changing element in future space architectures, with the potential to increase scale and reduce cost. However, before any decisions can be made on the inclusion of resources in exploration roadmaps or future scenarios some big questions need to be answered about the viability of different resource deposits and the processes for extraction and utilisation. The missions and measurements that will be required to answer these questions, and which are being prepared by agencies and others, can only be performed through the engagement and support of the science community. In answering questions about resources, data and knowledge will be generated that is of fundamental scientific importance. In supporting resource prospecting missions the science community will de facto generate new scientific knowledge. Science enables exploration and exploration enables science.

  13. Social determinants of health--a question of social or economic capital? Interaction effects of socioeconomic factors on health outcomes.

    PubMed

    Ahnquist, Johanna; Wamala, Sarah P; Lindstrom, Martin

    2012-03-01

    Social structures and socioeconomic patterns are the major determinants of population health. However, very few previous studies have simultaneously analysed the "social" and the "economic" indicators when addressing social determinants of health. We focus on the relevance of economic and social capital as health determinants by analysing various indicators. The aim of this paper was to analyse independent associations, and interactions, of lack of economic capital (economic hardships) and social capital (social participation, interpersonal and political/institutional trust) on various health outcomes. Data was derived from the 2009 Swedish National Survey of Public Health, based on a randomly selected representative sample of 23,153 men and 28,261 women aged 16-84 year, with a participation rate of 53.8%. Economic hardships were measured by a combined economic hardships measure including low household income, inability to meet expenses and lacking cash reserves. Social capital was measured by social participation, interpersonal (horizontal) trust and political (vertical/institutional trust) trust in parliament. Health outcomes included; (i) self-rated health, (i) psychological distress (GHQ-12) and (iii) musculoskeletal disorders. Results from multivariate logistic regression show that both measures of economic capital and low social capital were significantly associated with poor health status, with only a few exceptions. Significant interactive effects measured as synergy index were observed between economic hardships and all various types of social capital. The synergy indices ranged from 1.4 to 2.3. The present study adds to the evidence that both economic hardships and social capital contribute to a range of different health outcomes. Furthermore, when combined they potentiate the risk of poor health.

  14. Economic and physical determinants of the global distributions of crop pests and pathogens

    PubMed Central

    Bebber, Daniel P; Holmes, Timothy; Smith, David; Gurr, Sarah J

    2014-01-01

    Crop pests and pathogens pose a significant and growing threat to food security, but their geographical distributions are poorly understood. We present a global analysis of pest and pathogen distributions, to determine the roles of socioeconomic and biophysical factors in determining pest diversity, controlling for variation in observational capacity among countries. Known distributions of 1901 pests and pathogens were obtained from CABI. Linear models were used to partition the variation in pest species per country amongst predictors. Reported pest numbers increased with per capita gross domestic product (GDP), research expenditure and research capacity, and the influence of economics was greater in micro-organisms than in arthropods. Total crop production and crop diversity were the strongest physical predictors of pest numbers per country, but trade and tourism were insignificant once other factors were controlled. Islands reported more pests than mainland countries, but no latitudinal gradient in species richness was evident. Country wealth is likely to be a strong indicator of observational capacity, not just trade flow, as has been interpreted in invasive species studies. If every country had US levels of per capita GDP, then 205 ± 9 additional pests per country would be reported, suggesting that enhanced investment in pest observations will reveal the hidden threat of crop pests and pathogens. PMID:24517626

  15. Economic and physical determinants of the global distributions of crop pests and pathogens.

    PubMed

    Bebber, Daniel P; Holmes, Timothy; Smith, David; Gurr, Sarah J

    2014-05-01

    Crop pests and pathogens pose a significant and growing threat to food security, but their geographical distributions are poorly understood. We present a global analysis of pest and pathogen distributions, to determine the roles of socioeconomic and biophysical factors in determining pest diversity, controlling for variation in observational capacity among countries. Known distributions of 1901 pests and pathogens were obtained from CABI. Linear models were used to partition the variation in pest species per country amongst predictors. Reported pest numbers increased with per capita gross domestic product (GDP), research expenditure and research capacity, and the influence of economics was greater in micro-organisms than in arthropods. Total crop production and crop diversity were the strongest physical predictors of pest numbers per country, but trade and tourism were insignificant once other factors were controlled. Islands reported more pests than mainland countries, but no latitudinal gradient in species richness was evident. Country wealth is likely to be a strong indicator of observational capacity, not just trade flow, as has been interpreted in invasive species studies. If every country had US levels of per capita GDP, then 205 ± 9 additional pests per country would be reported, suggesting that enhanced investment in pest observations will reveal the hidden threat of crop pests and pathogens.

  16. Relative importance of climatic, geographic and socio-economic determinants of malaria in Malawi

    PubMed Central

    2013-01-01

    Background Malaria transmission is influenced by variations in meteorological conditions, which impact the biology of the parasite and its vector, but also socio-economic conditions, such as levels of urbanization, poverty and education, which impact human vulnerability and vector habitat. The many potential drivers of malaria, both extrinsic, such as climate, and intrinsic, such as population immunity are often difficult to disentangle. This presents a challenge for the modelling of malaria risk in space and time. Methods A statistical mixed model framework is proposed to model malaria risk at the district level in Malawi, using an age-stratified spatio-temporal dataset of malaria cases from July 2004 to June 2011. Several climatic, geographic and socio-economic factors thought to influence malaria incidence were tested in an exploratory model. In order to account for the unobserved confounding factors that influence malaria, which are not accounted for using measured covariates, a generalized linear mixed model was adopted, which included structured and unstructured spatial and temporal random effects. A hierarchical Bayesian framework using Markov chain Monte Carlo simulation was used for model fitting and prediction. Results Using a stepwise model selection procedure, several explanatory variables were identified to have significant associations with malaria including climatic, cartographic and socio-economic data. Once intervention variations, unobserved confounding factors and spatial correlation were considered in a Bayesian framework, a final model emerged with statistically significant predictor variables limited to average precipitation (quadratic relation) and average temperature during the three months previous to the month of interest. Conclusions When modelling malaria risk in Malawi it is important to account for spatial and temporal heterogeneity and correlation between districts. Once observed and unobserved confounding factors are allowed for

  17. Educational and economic determinants of food intake in Portuguese adults: a cross-sectional survey

    PubMed Central

    Moreira, Pedro A; Padrão, Patricia D

    2004-01-01

    Background Understanding the influences of educational and economic variables on food consumption may be useful to explain food behaviour and nutrition policymaking. The aim of this study was to evaluate the importance of educational and economic factors in determining food pattern in Portuguese adults. Methods A cross-sectional study in a representative sample of Portuguese adults (20977 women and 18663 men). Participants were distributed in four categories according to years of education (≤4, 5–9, 10–12, and >12) and income (≤314 euros, 315–547 euros, 548–815 euros, and >815 euros). Logistic regression models were fitted to estimate the magnitude of the association between food groups and education/income, adjusting for confounders. Results In both genders, the odds favouring milk, vegetable soup, vegetables, fruit, and fish consumption, increased significantly with education, for those having >12 years of education compared to those with ≤4 years; the odds favouring wine, and spirits consumption decreased significantly with education, for those having >12 years of education compared to those with ≤4 years. In males, the odds favouring starchy foods and meat consumption decreased significantly with income, while for milk, the odds increased with higher income (those having >815 euros compared to those with ≤314 euros). Conclusions The low and high income groups are or tend to be similar in regard to several food groups consumption, and access to education/information appears to be the key element to a better food pattern as indicated by higher frequency of milk, vegetable soup, vegetables, fruit, and fish consumption. PMID:15575953

  18. The Impact of Socio-Economic Determinants on the Vaccination Rates with Rotavirus and Human Papiloma Virus Vaccine

    PubMed Central

    GRDADOLNIK, Urška; SOČAN, Maja

    2016-01-01

    Background Socio-economic inequalities may have an impact on the uptake of selfpaid vaccines. The aim of the study was to identify the effect of some socio economic determinants on vaccination rates with self-paid human papilloma virus (HPV) and rotavirus (RV) vaccines. Methods Vaccination coverage data, available in electronic database cepljenje.net (administered by the National Institute of Public Health), were collected at administrative unit level. The socio-economic determinants (the average gross pay in euros, the unemployment rate, the educational and households structure, the population density, the number of inhabitants, the number of children aged from 0 to 4, the number of women aged from 15 to 30) were extracted from Statistical Office of the Republic of Slovenia web page. The strength of the correlation between socioeconomic variables and self-paid HPV and RV vaccination rates was determined. Results Rotavirus vaccination rates show a slight negative correlation with the number of residents per administrative unit (ρ=−0.29, p=0.04), and no correlation with other socio-economic variables. Likewise, no correlation has been found between HPV vaccination rates and the selected socio-economic variables. Conclusion Ecological study did not reveal any correlations between socio economic variables and vaccination rates with RV and HPV self-paid vaccines on administrative unit level. PMID:27647088

  19. Viability and Resilience of Languages in Competition

    PubMed Central

    Chapel, Laetitia; Castelló, Xavier; Bernard, Claire; Deffuant, Guillaume; Eguíluz, Víctor M.; Martin, Sophie; Miguel, Maxi San

    2010-01-01

    We study the viability and resilience of languages, using a simple dynamical model of two languages in competition. Assuming that public action can modify the prestige of a language in order to avoid language extinction, we analyze two cases: (i) the prestige can only take two values, (ii) it can take any value but its change at each time step is bounded. In both cases, we determine the viability kernel, that is, the set of states for which there exists an action policy maintaining the coexistence of the two languages, and we define such policies. We also study the resilience of the languages and identify configurations from where the system can return to the viability kernel (finite resilience), or where one of the languages is lead to disappear (zero resilience). Within our current framework, the maintenance of a bilingual society is shown to be possible by introducing the prestige of a language as a control variable. PMID:20126655

  20. Exercising choice: the economic determinants of physical activity behaviour of an employed population.

    PubMed

    Brown, Heather; Roberts, Jennifer

    2011-08-01

    Lack of physical activity is a major contributing factor to the worldwide obesity epidemic, and to the overall burden of disease. The deindustrialisation of developed economies and move to more sedentary employment has impacted on the opportunities of working individuals to participate in physical activity. This can have negative effects on productivity and worker health potentially influencing economic growth. Thus, it is important to determine the factors influencing the frequency of participation in physical activity for employed individuals. This paper uses a modified time allocation framework to explore this issue. We use data from the first six waves of the Household Income and Labour Dynamics of Australia survey (HILDA). The analysis examines frequency of participation in physical activity using a generalised random effects ordered probit model. We control for non-parallel cut-points between the physical activity categories and individual heterogeneity, as well as exploring differences across gender. The results indicate that there is a time trade-off between non-market work, market work, and the frequency of physical activity participation. This effect is moderated by gender. For example, dependent children have a larger negative effect on the frequency of physical activity participation for women. Education and marriage have a larger negative effect on the frequency of participation for men. The findings suggests that policies which make exercise more convenient, and hence decrease the opportunity cost of exercise, will help to encourage more frequent participation in physical activity for working adults.

  1. Application of Probabilistic Methods for the Determination of an Economically Robust HSCT Configuration

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri N.; Bandte, Oliver; Schrage, Daniel P.

    1996-01-01

    This paper outlines an approach for the determination of economically viable robust design solutions using the High Speed Civil Transport (HSCT) as a case study. Furthermore, the paper states the advantages of a probability based aircraft design over the traditional point design approach. It also proposes a new methodology called Robust Design Simulation (RDS) which treats customer satisfaction as the ultimate design objective. RDS is based on a probabilistic approach to aerospace systems design, which views the chosen objective as a distribution function introduced by so called noise or uncertainty variables. Since the designer has no control over these variables, a variability distribution is defined for each one of them. The cumulative effect of all these distributions causes the overall variability of the objective function. For cases where the selected objective function depends heavily on these noise variables, it may be desirable to obtain a design solution that minimizes this dependence. The paper outlines a step by step approach on how to achieve such a solution for the HSCT case study and introduces an evaluation criterion which guarantees the highest customer satisfaction. This customer satisfaction is expressed by the probability of achieving objective function values less than a desired target value.

  2. Phytochemical evaluation, antioxidant assay, antibacterial activity and determination of cell viability (J774 and THP1 alpha cell lines) of P. sylvestris leaf crude and methanol purified fractions

    PubMed Central

    Sharma, Dinesh C.; Shukla, Ritu; Ali, Jasarat; Sharma, Swati; Bajpai, Priti; Pathak, Neelam

    2016-01-01

    Phoenix sylvestris (Arecaceae family) known as Indian Date Palm has been identified as a component of traditional medicine against various ailments. The present study was focused on phytochemical screening of crude hexane, dichloromethane and methanol leaf extracts. The crude extracts showed the presence of alkaloids, flavonoids, and phenols in the plant leaves. In the study methanol extract was found most potent, so this extract was further fractionated by column chromatography and 9 methanol purified fractions (MPFs) were isolated. Most potential MPF8 (20:80 chloroform: methanol ratio fraction) significantly enhanced free radicals and antibacterial activity. The best MIC (Minimum inhibitory concentration) of MPF8 was investigated against M. luteus and E. coli at 1 mg/ml concentration. However, against other bacteria the MIC ranged from 1 mg/ml to 3 mg/ml. The GC-MS analysis showed the presence of many biologically active compounds such as alcohols, flavonoids, aromatic compounds, aldehydes, terpenoids fatty acid methyl esters, and phenolics. Pentadecanoic acid occupied maximum (52 %) area in GC-MS profiling. MPF8 was assayed for in-vitro cytotoxicity by MTT assay which confirms its less cytotoxicity at lower concentration and also significant ROS determination against J774 and THP1 cell lines after 2 and 4 hours. PMID:27047320

  3. Interactions between Cultural and Economic Determinants of Divorce in the Netherlands

    ERIC Educational Resources Information Center

    Kalmijn, Matthijs; De Graaf, Paul M.; Poortman, Annerigt

    2004-01-01

    This study examines the relationship between gendered family roles and divorce in The Netherlands. Cultural and economic aspects of this relationship are distinguished. Economic hypotheses argue that the likelihood of divorce is increased if women work for pay and have attractive labor market resources. Cultural hypotheses argue that divorce…

  4. Motivation and Math Skills as Determinants of First-Year Performance in Economics

    ERIC Educational Resources Information Center

    Arnold, Ivo J. M.; Straten, Jerry T.

    2012-01-01

    The importance of math skills for study success in economics has been widely researched. This article adds to the literature by combining information on students' math skills and their motivation. The authors are thus able to present a rich picture of why students succeed in their study of economics and to confirm previous findings that deficient…

  5. Determinants of Human Capital Formation and Economic Growth of African Countries

    ERIC Educational Resources Information Center

    Oketch, Moses O.

    2006-01-01

    Rapid economic growth and improving living standards have benefited almost all regions of the world since the industrial revolution. Africa stands out as one regional exception. While several factors such as civil wars and rampant corruption have been associated with poor economic performance of the African region in the international community,…

  6. Determinants of Wealth Fluctuation: Changes in Hard-To-Measure Economic Variables in a Panel Study

    PubMed Central

    Pfeffer, Fabian T.; Griffin, Jamie

    2017-01-01

    Measuring fluctuation in families’ economic conditions is the raison d’être of household panel studies. Accordingly, a particularly challenging critique is that extreme fluctuation in measured economic characteristics might indicate compounding measurement error rather than actual changes in families’ economic wellbeing. In this article, we address this claim by moving beyond the assumption that particularly large fluctuation in economic conditions might be too large to be realistic. Instead, we examine predictors of large fluctuation, capturing sources related to actual socio-economic changes as well as potential sources of measurement error. Using the Panel Study of Income Dynamics, we study between-wave changes in a dimension of economic wellbeing that is especially hard to measure, namely, net worth as an indicator of total family wealth. Our results demonstrate that even very large between-wave changes in net worth can be attributed to actual socio-economic and demographic processes. We do, however, also identify a potential source of measurement error that contributes to large wealth fluctuation, namely, the treatment of incomplete information, presenting a pervasive challenge for any longitudinal survey that includes questions on economic assets. Our results point to ways for improving wealth variables both in the data collection process (e.g., by measuring active savings) and in data processing (e.g., by improving imputation algorithms). PMID:28316752

  7. Factors Determining Student Retention of Economic Knowledge after Completing the Principles-of-Microeconomics Course.

    ERIC Educational Resources Information Center

    Kohen, Andrew I.; Kipps, Paul H.

    1979-01-01

    Reports results of a study of economics students to test the effect of time and other factors affecting retention, to develop an instrument to measure the rate of depreciation of the student's stock of economic knowledge, and to explore the implications of findings for the student's academic planning. (Author/KC)

  8. Viability, Advantages and Design Methodologies of M-Learning Delivery

    ERIC Educational Resources Information Center

    Zabel, Todd W.

    2010-01-01

    The purpose of this study was to examine the viability and principle design methodologies of Mobile Learning models in developing regions. Demographic and market studies were utilized to determine the viability of M-Learning delivery as well as best uses for such technologies and methods given socioeconomic and political conditions within the…

  9. Pilot test of Pickliq{reg_sign} process to determine energy and environmental benefits & economic feasibility

    SciTech Connect

    Olsen, D.R.

    1997-07-13

    Green Technology Group (GTG) was awarded Grant No. DE-FG01-96EE 15657 in the amount of $99,904 for a project to advance GTG`s Pickliq{reg_sign} Process in the Copper and Steel Industries. The use of the Pickliq{reg_sign} Process can significantly reduce the production of waste acids containing metal salts. The Pickliq{reg_sign} Process can save energy and eliminate hazardous waste in a typical copper rod or wire mill or a typical steel wire mill. The objective of this pilot project was to determine the magnitude of the economic, energy and environmental benefits of the Pickliq{reg_sign} Process in two applications within the metal processing industry. The effectiveness of the process has already been demonstrated at facilities cleaning iron and steel with sulfuric acid. 9207 companies are reported to use sulfuric and hydrochloric acid in the USA. The USEPA TRI statistics of acid not recycled in the US is 2.4 x 10{sup 9} lbs (net) for Hydrochloric Acid and 2.0 x 10{sup 9} lbs (net) for Sulfuric Acid. The energy cost of not reclaiming acid is 10.7 x 10{sup 6} BTU/ton for Hydrochloric Acid and 21.6 x 10{sup 6} BTU/Ton for Sulfuric Acid. This means that there is a very large market for the application of the Pickliq{reg_sign} Process and the widespread use of the process will bring significant world wide savings of energy to the environment.

  10. Understanding socio-economic determinants of childhood mortality: a retrospective analysis in Uganda

    PubMed Central

    2011-01-01

    Background Teso sub-region of Eastern Uganda had superior indices of childhood survival during the period 1959 to 1969 compared to the national average. We analysed the reasons that could explain this situation with a view of suggesting strategies for reducing childhood mortality. Methods We compared the childhood mortalities and their average annual reduction rate (AARR) of Teso sub-region with those of Uganda for the period 1959 to 1969. We also compared indicators of social economic well being (such as livestock per capita and per capita intake of protein/energy). In addition data was compared on other important determinants of child survival such as level of education and rate of urbanisation. Findings In 1969 the infant mortality rate (IMR) for Teso was 94 per 1000 live births compared to the 120 for Uganda. Between 1959 and 1969 the AARR for IMR for Teso was 4.57% compared to 3% for Uganda. It was interesting that the AARR for Teso was higher than that that of 4.4.% required to achieve millennium development goal number four (MDG4). The rate of urbanisation and the level of education were higher in Uganda compared to Teso during the same period. Teso had a per capita ownership of cattle of 1.12 compared to Uganda's 0.44. Teso sub region had about 3 times the amount of protein and about 2 times the amount of calories compared to Uganda. Conclusions We surmise that higher ownership of cattle and growing of high protein and energy foods might have been responsible for better childhood survival in Teso compared to Uganda. PMID:22070908

  11. Examining Gifted Students Who Are Economically At-Risk to Determine Factors that Influence Their Early Reading Success

    ERIC Educational Resources Information Center

    Bailey, Lora Battle

    2006-01-01

    The aim of this study was to determine whether the "Frequency with which parents read to their children, Preschool Exposure" and the initial "Age" that students "who are economically at-risk" were first exposed to significant literacy activities at home or in a preschool setting affected their reading grades.…

  12. Cost and Economics for Advanced Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Whitfield, Jeff

    1998-01-01

    Market sensitivity and weight-based cost estimating relationships are key drivers in determining the financial viability of advanced space launch vehicle designs. Due to decreasing space transportation budgets and increasing foreign competition, it has become essential for financial assessments of prospective launch vehicles to be performed during the conceptual design phase. As part of this financial assessment, it is imperative to understand the relationship between market volatility, the uncertainty of weight estimates, and the economic viability of an advanced space launch vehicle program. This paper reports the results of a study that evaluated the economic risk inherent in market variability and the uncertainty of developing weight estimates for an advanced space launch vehicle program. The purpose of this study was to determine the sensitivity of a business case for advanced space flight design with respect to the changing nature of market conditions and the complexity of determining accurate weight estimations during the conceptual design phase. The expected uncertainty associated with these two factors drives the economic risk of the overall program. The study incorporates Monte Carlo simulation techniques to determine the probability of attaining specific levels of economic performance when the market and weight parameters are allowed to vary. This structured approach toward uncertainties allows for the assessment of risks associated with a launch vehicle program's economic performance. This results in the determination of the value of the additional risk placed on the project by these two factors.

  13. Functional Cardiac Magnetic Resonance Imaging (MRI) in the Assessment of Myocardial Viability and Perfusion

    PubMed Central

    2003-01-01

    extent of hyperenhancement was significantly related to the likelihood of improvement in contractility after revascularization. However, the LVEF in the patient population was 43% prior to revascularization. It is important to know whether the technique has the same degree of accuracy in patients who have more severe LV dysfunction and who would most benefit from an assessment of myocardial viability. “Substantial” viability used as a measure of a patient’s ability to recover after revascularization has not been definitively reported (how much viability is enough?). Patients with severe LV dysfunction are more likely to have mixtures of surviving myocardium, including normal, infarcted, stunned and hibernating myocardium (Cowley et al., 1999). This may lead to a lack of homogeneity of response to testing and to revascularization and contribute to inter- and intra-study differences. There is a need for a large prospective study with adequate follow-up time for patients with CAD and LV dysfunction (LVEF<35%) comparing MRI and an alternate imaging technique. There is some evidence that MRI has comparable sensitivity, specificity and accuracy to PET for determining myocardial viability. However, there is a lack of evidence comparing the accuracy of these two techniques to predict LV function recovery. In addition, some studies refer to PET as the gold standard for the assessment of myocardial viability. Therefore, PET may be an ideal noninvasive imaging comparator to MRI for a prospective study with follow-up. To date, there is a lack of cost-effectiveness analyses (or any economic analyses) of functional cardiac MRI versus an alternate noninvasive imaging method for the assessment of myocardial viability/perfusion. Conclusion There is some evidence that the accuracy of functional cardiac MRI compares favourably with alternate imaging techniques for the assessment of myocardial viability and perfusion. There is insufficient evidence whether functional cardiac MRI can

  14. A survey of retirement intentions of baby boomers: an overview of health, social and economic determinants

    PubMed Central

    2014-01-01

    Background Governments have been implementing policies aimed at halting the trend towards early retirement for Baby Boomers. Public policies can have a strong effect on when a person retires and this analysis contributes to an improved understanding of retirement aspirations in regards to health, social, workplace and economic determinants. Methods In October 2011 a telephone survey was undertaken with participants aged 50 to 65 years who were in paid employment and who had been in the workforce for the previous three years. Participants were obtained from two identical South Australian cohort studies - the North West Adelaide Health Study and the Florey Adelaide Male Ageing Study. The results of the telephone survey were linked to the original cohort data. Data were weighted by sex, age, postcode and probability of selection in the household. Work related questions included how much they thought about their retirement, current occupation, employment status, type of workplace and hours worked per week. Health related questions included current smoking status, physical activity, body mass index, self-reported health status and overall life satisfaction. Uni-variable and multi-variable analyses were undertaken to compare the different associations between people who were and were not intending to retire. Results In total, 25.9% (n = 210) of people who were currently in paid employment indicated that they intend to retire completely from the workforce. The remainder indicated that they will continue to work (41.8% retire from full-time work but work part-time, 25.7% continue working part-time but reduce their current hours, and 6.7% never retire). The multi-variable results indicate that those with lower education, having a savings habit, and sales workers more likely to anticipate complete retirement. The self-employed, and those thinking only moderately about retirement, were more likely to extend their working life beyond age 65. Conclusion An important

  15. Economic, Social, and Cultural Determinants of Life Satisfaction: Are There Differences between Asia and Europe?

    ERIC Educational Resources Information Center

    Jagodzinski, Wolfgang

    2010-01-01

    This paper investigates the influence of the economic, social, and cultural variables on life satisfaction in Asia and Europe. The second section sets a unifying theoretical framework for all three domains by defining life satisfaction as a function of aspirations and expectations which in turn are affected by micro- and macro-level variables. On…

  16. One Generation of Self-Determination: Native American Economic Self-Reliance in New Mexico.

    ERIC Educational Resources Information Center

    Jojola, Theodore S.; Agoyo, Herman

    This paper examines changes in federal policy that have encouraged economic development by American Indian tribes, and presents examples from New Mexico. The Indian Reorganization Act of 1934 guaranteed federal provision of education and other services to the tribes, but the newly reorganized tribal governments were regulated almost exclusively by…

  17. Economic Determinants of Academic Failure and School Desertion in the Guatemala Highlands.

    ERIC Educational Resources Information Center

    Carvajal, Manuel J.; And Others

    1993-01-01

    Explores, from an economic perspective, elementary school system adequacy in the rural, indigenous Guatemalan highlands. Estimates least-squares coefficients and elasticities separately for academic failure and school abandonment for each of four indigenous groups. The model explains academic failure better than school desertion. A national policy…

  18. Determining How to Best Predict Navy Recruiting Using Various Economic Variables

    DTIC Science & Technology

    2015-03-01

    ADVERTISING, MARKET RESEARCH & STUDIES NEW RECRUIT SURVEYS .....................................................................................8 1...FIPS federal information processing code IPUMS-CPS integrated public use market data series current population survey JAMRS joint advertising... market research and studies NBER National Bureau of Economic Research NRC Navy Recruiting Command NRD Navy Recruiting District NRS Navy

  19. 41 CFR 101-5.104-2 - Basis for determining economic feasibility.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., or where such data must be supplemented by additional factual information, a formal feasibility study... feasibility study will be made only if provision of the proposed centralized service would involve the pooling... economic feasibility. 101-5.104-2 Section 101-5.104-2 Public Contracts and Property Management...

  20. Determining the economic liability of implementing irrigation on small-scale farming systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Small, limited resource farmers are often the primary providers of fresh foods for rural communities. However, they face often insurmountable economic challenges to staying in business. The small and limited resource farmer has declined at an alarming rate. The reasons for the decline or disappearan...

  1. An Approach to Determining the Market for Academic Positions: Application to the Discipline of Agricultural Economics

    ERIC Educational Resources Information Center

    Farrell, Terence; Casavant, Ken; Jessup, Eric

    2007-01-01

    The purpose of this paper is to present issues that are relevant to pursuing an academic career in the chosen discipline of each student. The application will be a general case study of agricultural economics. The analytical model will be used to evaluate options for Ph.D. graduates in a supply and demand context. The first issue presented is a…

  2. Demographic and socio-economic determinants of post-neonatal deaths in a special project area of rural northern India.

    PubMed

    Kabir, Zubair

    2003-07-01

    The demographic and socio-economic determinants of post-neonatal deaths (n = 475) in a special project area of rural northern India (Ballabgarh) were ascertained from 1991 to 1999 using the electronic database system of the project area for data extraction, and were compared with the eligible living children of the same age using a matched population-based case-control study design. Similar determinants were also ascertained in neonatal deaths (n = 212) using the same study design. After controlling for the potential confounders using conditional logistic regression analyses, lower caste (a proxy measure for low socio-economic conditions in rural India) was found to be significantly associated with higher post-neonatal deaths (OR = 2.21). Higher maternal age (>30 years) and fathers' lower educational levels were significantly associated with higher neonatal deaths, in addition to higher post-neonatal deaths in the same area.

  3. Low-level waste vitrification contact maintenance viability study

    SciTech Connect

    Leach, C.E., Westinghouse Hanford

    1996-07-12

    This study investigates the economic viability of contact maintenance in the Low-Level Waste Vitrification Facility, which is part of the Hanford Site Tank Waste Remediation System. This document was prepared by Flour Daniel, Inc., and transmitted to Westinghouse Hanford Company in September 1995.

  4. Socio-Economic and Cultural Determinants of Human African Trypanosomiasis at the Kenya – Uganda Transboundary

    PubMed Central

    Rutto, Jane Jemeli; Osano, Odipo; Thuranira, Elias Gitonga; Kurgat, Richard Kiptum; Odenyo, Victor Agab Omondi

    2013-01-01

    Background Kenya and Uganda have reported different Human African Trypanosomiasis incidences in the past more than three decades, with the latter recording more cases. This cross-sectional study assessed the demographic characteristics, tsetse and trypanosomiasis control practices, socio-economic and cultural risk factors influencing Trypanosoma brucei rhodesiense (T.b.r.) infection in Teso and Busia Districts, Western Kenya and Tororo and Busia Districts, Southeast Uganda. A conceptual framework was postulated to explain interactions of various socio-economic, cultural and tsetse control factors that predispose individuals and populations to HAT. Methods A cross-sectional household survey was conducted between April and October 2008. Four administrative districts reporting T.b.r and lying adjacent to each other at the international boundary of Kenya and Uganda were purposely selected. Household data collection was carried out in two villages that had experienced HAT and one other village that had no reported HAT case from 1977 to 2008 in each district. A structured questionnaire was administered to 384 randomly selected household heads or their representatives in each country. The percent of respondents giving a specific answer was reported. Secondary data was also obtained on socio-economic and political issues in both countries. Results Inadequate knowledge on the disease cycle and intervention measures contributed considerable barriers to HAT, and more so in Uganda than in Kenya. Gender-associated socio-cultural practices greatly predisposed individuals to HAT. Pesticides-based crop husbandry in the 1970's reportedly reduced vector population while vegetation of coffee and banana's and livestock husbandry directly increased occurrence of HAT. Livestock husbandry practices in the villages were strong predictors of HAT incidence. The residents in Kenya (6.7%) applied chemoprophylaxis and chemotherapeutic controls against trypanosomiasis to a larger extent than

  5. A Model for Determining Economic Retention Levels of Expendable Inventory Items

    DTIC Science & Technology

    1975-08-01

    to describe the cumulative effect of the various factors. For the purpose of this study, such a broad definition of the term inflation seems...adequate. The assessment of reprocurement costs should logically account for the effect of inflation on the amounts mentioned above. Since holding costs...analysis of economic retention less than straight- forward. However« due to the effect of inflation on cost based decisions« it should be addressed as an

  6. A Guide for Determining Which Teaching Methodology to Utilize in Economic Education: Trying to Improve How Economic Information Is Communicated to Students

    ERIC Educational Resources Information Center

    Wentland, Daniel

    2004-01-01

    In this article, a practical framework for classifying various economic education teaching methodologies is established. This framework contributes to the literature regarding economic education by fostering a better understanding of how various teaching methodologies fit within the scope of economic education while also providing educators with…

  7. Television Economics.

    ERIC Educational Resources Information Center

    Owen, Bruce M.; And Others

    Intended as an introduction to the economics of commercial television for the general reader, this volume considers the theory and analytical basis of television and the policy implications of those economics. Part I considers the economics of television markets with particular attention of the determinants of viewer markets; the supply of…

  8. Environmental, political, and economic determinants of water quality monitoring in Europe

    NASA Astrophysics Data System (ADS)

    Beck, Lucas; Bernauer, Thomas; Kalbhenn, Anna

    2010-11-01

    Effective monitoring is essential for effective pollution control in national and international water systems. To what extent are countries' monitoring choices driven by environmental criteria, as they should be? And to what extent are they also influenced by other factors, such as political and economic conditions? To address these questions, we describe and explain the evolution of one of the most important international environmental monitoring networks in Europe, the one for water quality, in the time period 1965-2004. We develop a geographic information system that contains information on the location of several thousand active monitoring stations in Europe. Using multivariate statistics, we then examine whether and to what extent the spatial and temporal clustering of monitoring intensity is driven by environmental, political, and economic factors. The results show that monitoring intensity is higher in river basins exposed to greater environmental pressure. However, political and economic factors also play a strong role in monitoring decisions: democracy, income, and peer pressure are conducive to monitoring intensity, and monitoring intensity generally increases over time. Moreover, even though monitoring is more intense in international upstream-downstream settings, we observe only a weak bias toward more monitoring downstream of international borders. In contrast, negative effects of European Union (EU) membership and runup to the EU's Water Framework Directive are potential reasons for concern. Our results strongly suggest that international coordination and standardization of water quality monitoring should be intensified. It will be interesting to apply our analytical approach also to other national and international monitoring networks, for instance, the U.S. National Water-Quality Assessment Program or the European Monitoring and Evaluation Program for air pollution.

  9. The global economic and regulatory determinants of household food waste generation: A cross-country analysis.

    PubMed

    Chalak, Ali; Abou-Daher, Chaza; Chaaban, Jad; Abiad, Mohamad G

    2016-02-01

    Food is generally wasted all along the supply chain, with an estimated loss of 35percent generated at the consumer level. Consequently, household food waste constitutes a sizable proportion of the total waste generated throughout the food supply chain. Yet such wastes vary drastically between developed and developing countries. Using data collected from 44 countries with various income levels, this paper investigates the impact of legislation and economic incentives on household food waste generation. The obtained results indicate that well-defined regulations, policies and strategies are more effective than fiscal measures in mitigating household food waste generation.

  10. Technique to determine contamination exposure routes and the economic efficiency of folded paper-towel dispensing.

    PubMed

    Harrison, Wendy A; Griffith, Christopher J; Michaels, Barry; Ayers, Troy

    2003-04-01

    Handwashing and hand drying are key elements of infection control. Paper towels are generally accepted as the most hygienic means of drying hands and are often distributed from generic dispensers. Effective dispensing of towels is of importance economically and may influence infection control objectives if hands become contaminated during hand drying. In this study, a method to identify potential exposure routes for hand contamination and evaluate the efficiency of paper-towel dispensing is described and applied to 5 different folded paper towels using a generic wall-mounted dispenser. A total of 18 male and female participants of varying heights participated in pull testing of 400 paper towels each, in controlled hand-drying simulations. All events having the potential for hand contamination, including towel jamming, towels falling onto the floor, and incidental contact of paper exits, were monitored and documented. There was considerable variation in dispensing efficiency between different towel brands. One towel (Z) had significantly (P <.05) superior dispensing properties from the generic dispenser. Participants of a shorter height obtained a lower incidence of dispensing malfunctions using all towel products and type. The results indicated likely contamination exposure routes and wastage levels for each towel type. Environmental service managers and infection control practitioners should carefully consider, for economic and infection control reasons, the siting and design of towel dispensers and the types of towel purchased.

  11. The Family Farm in California. Final Report of the Small Farm Viability Project.

    ERIC Educational Resources Information Center

    California State Office of Economic Development, Sacramento. Community Services Administration.

    Most of California's farms are relatively small, family run operations, and their future has been called into question by current agricultural trends. The Small Farm Viability Planning Project was initiated to identify obstacles to small farm economic viability and make recommendations to the state on policies and actions that might reduce these…

  12. Creating a Sustainability Scorecard as a predictive tool for measuring the complex social, economic and environmental impacts of industries, a case study: assessing the viability and sustainability of the dairy industry.

    PubMed

    Buys, L; Mengersen, K; Johnson, S; van Buuren, N; Chauvin, A

    2014-01-15

    Sustainability is a key driver for decisions in the management and future development of industries. The World Commission on Environment and Development (WCED, 1987) outlined imperatives which need to be met for environmental, economic and social sustainability. Development of strategies for measuring and improving sustainability in and across these domains, however, has been hindered by intense debate between advocates for one approach fearing that efforts by those who advocate for another could have unintended adverse impacts. Studies attempting to compare the sustainability performance of countries and industries have also found ratings of performance quite variable depending on the sustainability indices used. Quantifying and comparing the sustainability of industries across the triple bottom line of economy, environment and social impact continues to be problematic. Using the Australian dairy industry as a case study, a Sustainability Scorecard, developed as a Bayesian network model, is proposed as an adaptable tool to enable informed assessment, dialogue and negotiation of strategies at a global level as well as being suitable for developing local solutions.

  13. Determining economic benefits of satellite data in short-range forecasting

    NASA Technical Reports Server (NTRS)

    Suchman, D.; Auvine, B.; Hinton, B.

    1981-01-01

    The chances of enhanced short term weather predictions and economic benefits from the use of GOES satellite data were examined. Results for a meteorological consulting firm before and after the introduction of GOES data were chosen as the method, and monetary benefits were selected as the measure. Services were provided for use by road and street departments, commodities dealers, and marine clients of the consulting firm. The Man-computer Interactive Data Access Program (McIDAS) was employed to furnish 1/2 hour visual or IR imagery for remote access. The commodities clients reconnected the GOES real-time imagery once the study was completed, while the consulting firm, which was personnel and not equipment intensive, did not. Further development of the flexibility of access to the GOES data and improvements in the projected grids are indicated.

  14. Pneumocystis melanins confer enhanced organism viability.

    PubMed

    Icenhour, Crystal R; Kottom, Theodore J; Limper, Andrew H

    2006-06-01

    Pneumocystis continues to represent an important opportunistic fungal pathogen of those with compromised immunity. Thus, it is crucial to identify factors that affect its viability and pathogenicity. We previously reported the first identification of melanins in Pneumocystis. In the present study, we sought to further characterize these components and define the function for these melanins. Melanins extracted from Pneumocystis and melanized Pneumocystis cells were analyzed by electron spin resonance spectroscopy, revealing spectra consistent with melanins from other fungi. Immunofluorescence assays using anti-melanin monoclonal antibodies showed that melanins are widely present across Pneumocystis host species, including mouse-, ferret-, and human-derived Pneumocystis organisms, as well as Pneumocystis carinii derived from rat. Using immunoelectron microscopy, melanins were found to localize to the cell wall and cytoplasm of P. carinii cysts, as well as to intracystic bodies within mature cysts. Next, the role of melanins on the maintenance of Pneumocystis viability was determined by using quantitative reverse transcription-PCR measurement of the heat shock protein mRNA under adverse environmental conditions. Using a new method to promote the melanization of Pneumocystis, we observed that strongly melanized Pneumocystis retained viability to a greater degree when exposed to UV irradiation or desiccation compared to less-pigmented organisms. These studies support our previous identification of Pneumocystis melanins across the genus, further characterize these Pneumocystis components, and demonstrate that melanins protect Pneumocystis from environmental stressors.

  15. Verification of energy's role as a determinant of US economic activity

    SciTech Connect

    Santini, D.J.

    1987-10-01

    A series of single-equation dynamic regression models are constructed to test the hypotheses that both ''thermodynamic'' and economic-efficiency (t-efficiency and e-efficiency, respectively) configurations of lagged energy variables are statistically informative separately and jointly about subsequent changes in real gross national product (GNP) per capita and in unemployment rate. Separately, t-efficiency is based on quantity of energy used per unit of GNP, while e-efficiency is based on real price of tested energy variables. Used jointly, the two measure real energy cost per unit of real GNP. Tested subperiods are within the 1890-1985 period. Macroeconomic activity is found to be much less informative about energy variables that are energy variables about macroeconomic activity. One-way tests are conducted in which the informativeness of major e-efficiency (wholesale price) variables and budget-share variables about subsequent macroeconomic activity are compared to the informativeness of the e-efficiency energy variable and the combined e- and t-efficiencies energy variable respectively. The energy variables are found to represent the only major category of expenditure whose statistical tests for informativeness about subsequent macroeconomic activity result in coefficient signs that consistently imply a statistically significant negative effect on subsequent macroeconomic activity in the full 1890-1985 period. 64 refs., 14 tabs.

  16. Sulfite determination by a biosensor based on bay leaf tissue homogenate: very simple and economical method.

    PubMed

    Teke, Mustafa; Sezgintürk, Mustafa Kemal; Dinçkaya, Erhan

    2009-01-01

    Of all the food additives for which the FDA has received adverse reaction reports, the ones that most closely resemble true allergens are sulfur-based preservatives. Sulfites are used primarily as antioxidants to prevent or reduce discoloration of light-colored fruits and vegetables, such as dried apples and potatoes, and to inhibit the growth of microorganisms in fermented foods such as wine. This work aims to prepare an electrochemical biosensor based on bay leaf tissue homogenate that contains polyphenol oxidase enzyme abundantly for sulfite detection in foods. The principle of the biosensor is based on the inhibition effect of sulfites on polyphenol oxidase in the bioactive layer. Optimum conditions for the biosensor, such as temperature and pH, were investigated. Some stability parameters of the biosensor were also identified. The biosensor showed a linear calibration graph in the range of 25-100 microM sulfite. The biosensor presents a very simple, economical, reliable, and feasible method for sulfite detection in foods.

  17. 28 CFR 104.45 - Determination of presumed economic loss for claimants who suffered physical harm.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... determination of disability made by the Social Security Administration as evidence of disability without any... by the claimant, regarding the actual amount of work that the claimant has missed or will miss... adjusting the loss based upon the extent of the victim's physical harm. (1) Disability; in general....

  18. Socio-economic determinants of nutritional status of children in rural peninsular Malaysia.

    PubMed

    Marjan, Z M; Taib, M N; Lin, K G; Siong, T E

    1998-12-01

    The data presented is part of the findings from a four-year collaborative research project between Universiti Putra Malaysia, the Institute for Medical Research and the Ministry of Health Malaysia. The project assessed the nutritional status of the major functional groups in Peninsular Malaysia. Mukim Sayong and Pulau Kemiri in the District of Kuala Kangsar, Perak were two of the subdistricts selected to represent small rubber holdings in Peninsular Malaysia. This paper attempts to analyse the socio-economic profile of the households and the nutritional status of children below 9 years of age. A total of 307 households were studied. Approximately 63% of the households were involved in rubber activities and the majority of them were hired tappers. The average monthly income of the households was RM467 and the income ranged between RM30 to RM2120. Based on the per capita poverty line income of RM84.38, it was found that 14.1% of the households earned less than RM42.19, which can be considered as hard-core poor, while 32.7% were poor (monthly per capita income between RM42.19 and RM84.38). Slightly more than half (52.7%) earned income above the poverty line. The average family size was 4.5, ranging from 1 through to 16. The majority of the heads of households (56.6%) had between 3 and 6 years of education, and 14.5% did not receive any formal education. The prevalence of stunting among children 0-5 years of age was 26%, while 31.5% were underweight and 3.8% wasted. Among children aged between 5 and 9 years, almost the same pattern of nutritional status was noted. The overall percentages of stunting, underweight and wasting among these children were 29.2%, 26.1% and 0.62%, respectively. Analysis on nutritional status according to income level showed a noticeable difference in the prevalence of malnutrition in children above and below the poverty line income. The Student's t-test indicated significant differences in weight-for-age and weight-for-height between the two

  19. Determining a sustainable and economically optimal wastewater treatment and discharge strategy.

    PubMed

    Hardisty, Paul E; Sivapalan, Mayuran; Humphries, Robert

    2013-01-15

    the Corporation are all worse off when treatment levels are pushed beyond what is economic and sustainable.

  20. A metasynthesis of qualitative studies regarding opinions and perceptions about barriers and determinants of health services’ accessibility in economic migrants

    PubMed Central

    2012-01-01

    Background Access to health services is an important health determinant. New research in health equity is required, especially amongst economic migrants from developing countries. Studies conducted on the use of health services by migrant populations highlight existing gaps in understanding which factors affect access to these services from a qualitative perspective. We aim to describe the views of the migrants regarding barriers and determinants of access to health services in the international literature (1997–2011). Methods A systematic review was conducted for Qualitative research papers (English/Spanish) published in 13 electronic databases. A selection of articles that accomplished the inclusion criteria and a quality evaluation of the studies were carried out. The findings of the selected studies were synthesised by means of metasynthesis using different analysis categories according to Andersen’s conceptual framework of access and use of health services and by incorporating other emergent categories. Results We located 3,025 titles, 36 studies achieved the inclusion criteria. After quality evaluation, 28 articles were definitively synthesised. 12 studies (46.2%) were carried out in the U.S and 11 studies (42.3%) dealt with primary care services. The participating population varied depending mainly on type of host country. Barriers were described, such as the lack of communication between health services providers and migrants, due to idiomatic difficulties and cultural differences. Other barriers were linked to the economic system, the health service characteristics and the legislation in each country. This situation has consequences for the lack of health control by migrants and their social vulnerability. Conclusions Economic migrants faced individual and structural barriers to the health services in host countries, especially those with undocumented situation and those experimented idiomatic difficulties. Strategies to improve the structures of

  1. A Model to Determine the Economic Life of Air Force Motor Vehicles.

    DTIC Science & Technology

    1987-09-01

    62 Model Interpretation . . . . . . . . . . . 66 Recommendations for Model Applications 67 Recommendations for Further Study .... 68 Conclusion...process, not the product. Therefore, only one type of vehicle was studied to determine the feasibility of the model itself before spending the time and...followed by the scope and limitations for this study . Chapter one concluded by defining some of the terms used in this thesis. 13 S.AME~a II. Literature

  2. On the socio-economic determinants of antenatal care utilization in Azerbaijan: evidence and policy implications for reforms.

    PubMed

    Habibov, Nazim N

    2011-04-01

    Azerbaijan is a country with one of the highest child mortality rates in the regions of Eastern Europe and the former Soviet Union. Drawing on the nationally representative Demographic and Health Survey, this study examines the utilization of antenatal care in Azerbaijan to identify the socio-economic determinants of the usage, and its frequency, timing and quality. Consequently, binomial logit, two ordered logit and negative binomial regression models are specified to estimate the effect of various socio-economic characteristics on the likelihood of utilization. Place of living is an important determinant of antenatal healthcare utilization in Azerbaijan. It is important in determining the likelihood of utilization, its timing and quality of care received, whereas it is not significant in the model predicting the frequency of antenatal utilization. Women's education is also significant in three models out of four. Education is important in explaining the frequency and timing of utilization as well as the quality of services received, but it is not significant in predicting the likelihood of utilization. Wealth gradient is another important determinant of antenatal care utilization in Azerbaijan inasmuch as it is significant in explaining the likelihood of prenatal care utilization and its frequency. In addition, two variables, birth order and desirability of the last child or current pregnancy, are significant only in explaining the likelihood of utilization. Therefore, we confirm the findings of previous studies, which reported that the utilization of prenatal health care is a multistage process in which decisions are sequential. Although the same set of factors may affect decision-making at all stages, the effect of these factors is different at different stages. Implications for reforms in the healthcare sector to improve antenatal care utilization in Azerbaijan are provided and discussed.

  3. Bioluminescence assay for cell viability.

    PubMed

    Lomakina, G Yu; Modestova, Yu A; Ugarova, N N

    2015-06-01

    Theoretical aspects of the adenosine triphosphate bioluminescence assay based on the use of the firefly luciferin-luciferase system are considered, as well as its application for assessing cell viability in microbiology, sanitation, medicine, and ecology. Various approaches for the analysis of individual or mixed cultures of microorganisms are presented, and capabilities of the method for investigation of biological processes in live cells including necrosis, apoptosis, as well as for investigation of the dynamics of metabolism are described.

  4. Socio-Economic Status Determines Risk of Receptive Syringe Sharing Behaviors among Iranian Drug Injectors; A National Study

    PubMed Central

    Assari, Shervin; Ahmadi, Khodabakhsh; Rezazade, Majid

    2015-01-01

    Background: Although needle and syringe sharing is one of the main routs of transmission of HIV in several countries in the middle east, very little is known about how socio-economic status of injecting drug users (IDUs) is linked to the receptive syringe sharing behaviors in these countries. Aim: To study socio-economic correlates of receptive needle and syringe sharing among IDUs in Iran. Methods: The study used data from the Unhide Risk Study, a national survey of IDUs. This study sampled 636 IDUs (91% male) via snowball sampling from eight provinces in Iran in 2009. Socio-demographic and drug use characteristics were collected. We used a logistic regression to determine factors associated with receptive needle and syringe sharing during the past 6 months. Results: From 636 IDUs enrolled in this study, 68% (n = 434) reported receptive needle and syringe sharing behaviors in the past 6 months. Odds of receptive needle and syringe sharing in the past 6 months was lower among IDUs who were male [odds ratios (OR) = 0.29, 95% confidence interval (CI) = 0.12–0.70], had higher education (OR = 0.74, 95% CI = 0.64–0.86) but higher among those who were unemployed (OR = 4.05, 95% CI = 1.50–10.94), and were single (OR = 1.47, 95% CI = 1.02–2.11). Conclusion: This study presented factors associated with risk of receptive needle and syringe sharing among Iranian IDUs. This information may be used for HIV prevention and harm reduction purposes. Socio-economic status of Iranian IDUs may be closely linked to high-risk injecting behaviors among them. PMID:25852577

  5. Local knowledge and socio-economic determinants of traditional medicines' utilization in livestock health management in Southwest Nigeria

    PubMed Central

    2012-01-01

    Smallholder livestock farmers in Nigeria utilize traditional medicines derived from medicinal plants (PMs) for the maintenance of their animals' health. This study was designed to determine the PMs used in the study area and their level of utilization by livestock farmers, compare the level of utilization of PMs across the three states surveyed and identify the socio-economic factors influencing farmer's utilization of PMs. Thirty-five PMs were identified. Farmers had considerable knowledge about the identified PMs but about 80.0% of them used the PMs to poor/moderate extent. There were statistical differences in the utilization level of PMs among the three states. Six socio-economic variables were found to be statistically significant in influencing PMs' utilization. Farmer's age, household size, distance to the nearest veterinary hospital/clinic and extent of travels, had positive effects while negative effects were exhibited by farm income and number of heads of livestock. It was concluded that there was considerable knowledge about PMs and that utilization of PMs varied between the three states. It was recommended that local knowledge of PMs be preserved in the study area through screening and documentation. PMID:22239949

  6. Hierarchical Bayesian Spatio-Temporal Analysis of Climatic and Socio-Economic Determinants of Rocky Mountain Spotted Fever.

    PubMed

    Raghavan, Ram K; Goodin, Douglas G; Neises, Daniel; Anderson, Gary A; Ganta, Roman R

    2016-01-01

    This study aims to examine the spatio-temporal dynamics of Rocky Mountain spotted fever (RMSF) prevalence in four contiguous states of Midwestern United States, and to determine the impact of environmental and socio-economic factors associated with this disease. Bayesian hierarchical models were used to quantify space and time only trends and spatio-temporal interaction effect in the case reports submitted to the state health departments in the region. Various socio-economic, environmental and climatic covariates screened a priori in a bivariate procedure were added to a main-effects Bayesian model in progressive steps to evaluate important drivers of RMSF space-time patterns in the region. Our results show a steady increase in RMSF incidence over the study period to newer geographic areas, and the posterior probabilities of county-specific trends indicate clustering of high risk counties in the central and southern parts of the study region. At the spatial scale of a county, the prevalence levels of RMSF is influenced by poverty status, average relative humidity, and average land surface temperature (>35°C) in the region, and the relevance of these factors in the context of climate-change impacts on tick-borne diseases are discussed.

  7. Hierarchical Bayesian Spatio–Temporal Analysis of Climatic and Socio–Economic Determinants of Rocky Mountain Spotted Fever

    PubMed Central

    Raghavan, Ram K.; Goodin, Douglas G.; Neises, Daniel; Anderson, Gary A.; Ganta, Roman R.

    2016-01-01

    This study aims to examine the spatio-temporal dynamics of Rocky Mountain spotted fever (RMSF) prevalence in four contiguous states of Midwestern United States, and to determine the impact of environmental and socio–economic factors associated with this disease. Bayesian hierarchical models were used to quantify space and time only trends and spatio–temporal interaction effect in the case reports submitted to the state health departments in the region. Various socio–economic, environmental and climatic covariates screened a priori in a bivariate procedure were added to a main–effects Bayesian model in progressive steps to evaluate important drivers of RMSF space-time patterns in the region. Our results show a steady increase in RMSF incidence over the study period to newer geographic areas, and the posterior probabilities of county-specific trends indicate clustering of high risk counties in the central and southern parts of the study region. At the spatial scale of a county, the prevalence levels of RMSF is influenced by poverty status, average relative humidity, and average land surface temperature (>35°C) in the region, and the relevance of these factors in the context of climate–change impacts on tick–borne diseases are discussed. PMID:26942604

  8. Storage Viability and Optimization Web Service

    SciTech Connect

    Stadler, Michael; Marnay, Christ; Lai, Judy; Siddiqui, Afzal; Limpaitoon, Tanachai; Phan, Trucy; Megel, Olivier; Chang, Jessica; DeForest, Nicholas

    2010-10-11

    Non-residential sectors offer many promising applications for electrical storage (batteries) and photovoltaics (PVs). However, choosing and operating storage under complex tariff structures poses a daunting technical and economic problem that may discourage potential customers and result in lost carbon and economic savings. Equipment vendors are unlikely to provide adequate environmental analysis or unbiased economic results to potential clients, and are even less likely to completely describe the robustness of choices in the face of changing fuel prices and tariffs. Given these considerations, researchers at Lawrence Berkeley National Laboratory (LBNL) have designed the Storage Viability and Optimization Web Service (SVOW): a tool that helps building owners, operators and managers to decide if storage technologies and PVs merit deeper analysis. SVOW is an open access, web-based energy storage and PV analysis calculator, accessible by secure remote login. Upon first login, the user sees an overview of the parameters: load profile, tariff, technologies, and solar radiation location. Each parameter has a pull-down list of possible predefined inputs and users may upload their own as necessary. Since the non-residential sectors encompass a broad range of facilities with fundamentally different characteristics, the tool starts by asking the users to select a load profile from a limited cohort group of example facilities. The example facilities are categorized according to their North American Industry Classification System (NAICS) code. After the load profile selection, users select a predefined tariff or use the widget to create their own. The technologies and solar radiation menus operate in a similar fashion. After these four parameters have been inputted, the users have to select an optimization setting as well as an optimization objective. The analytic engine of SVOW is LBNL?s Distributed Energy Resources Customer Adoption Model (DER-CAM), which is a mixed

  9. Socio-economic & demographic determinants of hypertension & knowledge, practices & risk behaviour of tribals in India

    PubMed Central

    Laxmaiah, A.; Meshram, I.I.; Arlappa, N.; Balakrishna, N.; Rao, K. Mallikharjuna; Reddy, Ch Gal; Ravindranath, M.; Kumar, Sharad; Kumar, Hari; Brahmam, G.N.V.

    2015-01-01

    Background & objectives: An increase in prevalence of hypertension has been observed in all ethnic groups in India. The objective of the present study was to estimate prevalence and determinants of hypertension among tribals and their awareness, treatment practices and risk behaviours in nine States of India. Methods: A community based cross-sectional study adopting multistage random sampling procedure was carried out. About 120 Integrated Tribal Development Authority villages were selected randomly from each State. From each village, 40 households were covered randomly. All men and women ≥ 20 yr of age in the selected households were included for various investigations. Results: A total of 21141 men and 26260 women participated in the study. The prevalence of hypertension after age adjustment was 27.1 and 26.4 per cent among men and women, respectively. It was higher in the States of Odisha (50-54.4%) and Kerala (36.7-45%) and lowest in Gujarat (7-11.5%). The risk of hypertension was 6-8 times higher in elderly people and 2-3 times in 35-59 yr compared with 20-34 yr. Only <10 per cent of men and women were known hypertensives and more than half on treatment (55-68%). Men with general and abdominal obesity were at 1.69 (CI: 1.43-2.01) and 2.42 (CI: 2.01-2.91) times higher risk of hypertension, respectively, while it was 2.03 (CI=1.77-2.33) and 2.35 (CI 2.12-2.60) times higher in women. Those using tobacco and consuming alcohol were at a higher risk of hypertension compared with the non users. Interpretation & conclusions: The study revealed high prevalence of hypertension among tribals in India. Age, literacy, physical activity, consumption of tobacco, alcohol and obesity were significantly associated with hypertension. Awareness and knowledge about hypertension and health seeking behaviour were low. Appropriate intervention strategies need to be adopted to increase awareness and treatment practices of hypertension among tribals. PMID:26139790

  10. Cell viability test after laser guidance

    NASA Astrophysics Data System (ADS)

    Rosenbalm, Tabitha N.; Owens, Sarah; Bakken, Daniel; Gao, Bruce Z.

    2006-02-01

    To precisely control the position of multiple types of cells in a coculture for the study of cell-cell interactions, we have developed a laser micropatterning technique. The technique employs the optical forces generated by a weakly focused laser beam. In the beam's focal region, the optical force draws microparticles, such as cells, into the center of the beam, propels them along the beam axis, and guides them onto a target surface. Specific patterns are created through computercontrolled micromanipulation of the substrate relative to the laser beam. Preliminary data have demonstrated cell viability after laser guidance. This project was designed to systematically vary the controllable laser parameters, namely, intensity and exposure time of the laser on single cells, and thus determine the laser parameters that allow negligible cell damage with functional cellular position control. To accomplish this goal, embryonic day 7 (E7) chick forebrain neurons were cultured in 35 mm petri dishes. Control and test cells were selected one hour after cell placement to allow cell attachment. Test cells were subjected to the laser at the focal region. The experimental parameters were chosen as: wavelength - 800 nm, intensities - 100 mW, 200 mW, and 300 mW, and exposure times - 10 s and 60 s. Results were analyzed based on neurite outgrowth and the Live/Dead assay (Viability/Cytoxicity kit from Molecular Probes). No statistical difference (p >> 0.1, student t-test) in viability or function was found between the control neurons and those exposed to the laser. This confirms that laser guidance seems to be a promising method for cellular manipulation.

  11. Rapid onsite assessment of spore viability.

    SciTech Connect

    Branda, Steven; Lane, Todd W.; VanderNoot, Victoria A.; Gaucher, Sara P.; Jokerst, Amanda S.

    2005-12-01

    This one year LDRD addresses problems of threat assessment and restoration of facilities following a bioterror incident like the incident that closed down mail facilities in late 2001. Facilities that are contaminated with pathogenic spores such as B. anthracis spores must be shut down while they are treated with a sporicidal agent and the effectiveness of the treatment is ascertained. This process involves measuring the viability of spore test strips, laid out in a grid throughout the facility; the CDC accepted methodologies require transporting the samples to a laboratory and carrying out a 48 hr outgrowth experiment. We proposed developing a technique that will ultimately lead to a fieldable microfluidic device that can rapidly assess (ideally less than 30 min) spore viability and effectiveness of sporicidal treatment, returning facilities to use in hours not days. The proposed method will determine viability of spores by detecting early protein synthesis after chemical germination. During this year, we established the feasibility of this approach and gathered preliminary results that should fuel a future more comprehensive effort. Such a proposal is currently under review with the NIH. Proteomic signatures of Bacillus spores and vegetative cells were assessed by both slab gel electrophoresis as well as microchip based gel electrophoresis employing sensitive laser-induced fluorescence detection. The conditions for germination using a number of chemical germinants were evaluated and optimized and the time course of protein synthesis was ascertained. Microseparations were carried out using both viable spores and spores inactivated by two different methods. A select number of the early synthesis proteins were digested into peptides for analysis by mass spectrometry.

  12. Economic viability of photovoltaic power for development assistance applications

    NASA Technical Reports Server (NTRS)

    Bifano, W. J.

    1982-01-01

    This paper briefly discusses the development assistance market and examines a number of specific photovoltaic (PV) development assistance field tests, including water pumping/grain grinding (Tangaye, Upper Volta), vaccine refrigerators slated for deployment in 24 countries, rural medical centers to be installed in Ecuador, Guyana, Kenya and Zimbabwe, and remote earth stations to be deployed in the near future. A comparison of levelized energy cost for diesel generators and PV systems covering a range of annual energy consumptions is also included. The analysis does not consider potential societal, environmental or political benefits associated with PV power. PV systems are shown to be competitive with diesel generators, based on life cycle cost considerations, assuming a system price of $20/W(peak), for applications having an annual energy demand of up to 6000 kilowatt-hours per year.

  13. The market viability of nuclear hydrogen technologies.

    SciTech Connect

    Botterud, A.; Conzelmann, G.; Petri, M. C.; Yildiz, B.

    2007-04-06

    The Department of Energy Office of Nuclear Energy is supporting system studies to gain a better understanding of nuclear power's potential role in a hydrogen economy and what hydrogen production technologies show the most promise. This assessment includes identifying commercial hydrogen applications and their requirements, comparing the characteristics of nuclear hydrogen systems to those market requirements, evaluating nuclear hydrogen configuration options within a given market, and identifying the key drivers and thresholds for market viability of nuclear hydrogen options. One of the objectives of the current analysis phase is to determine how nuclear hydrogen technologies could evolve under a number of different futures. The outputs of our work will eventually be used in a larger hydrogen infrastructure and market analysis conducted for DOE-EE using a system-level market simulation tool now underway. This report expands on our previous work by moving beyond simple levelized cost calculations and looking at profitability, risk, and uncertainty from an investor's perspective. We analyze a number of technologies and quantify the value of certain technology and operating characteristics. Our model to assess the profitability of the above technologies is based on Real Options Theory and calculates the discounted profits from investing in each of the production facilities. We use Monte-Carlo simulations to represent the uncertainty in hydrogen and electricity prices. The model computes both the expected value and the distribution of discounted profits from a production plant. We also quantify the value of the option to switch between hydrogen and electricity production in order to maximize investor profits. Uncertainty in electricity and hydrogen prices can be represented with two different stochastic processes: Geometric Brownian Motion (GBM) and Mean Reversion (MR). Our analysis finds that the flexibility to switch between hydrogen and electricity leads to

  14. Nutritional and socio-economic determinants of cognitive function and educational achievement of Aboriginal schoolchildren in rural Malaysia.

    PubMed

    Al-Mekhlafi, Hesham M; Mahdy, Mohammed A; Sallam, Atiya A; Ariffin, W A; Al-Mekhlafi, Abdulsalam M; Amran, Adel A; Surin, Johari

    2011-10-01

    A community-based cross-sectional study was carried out among Aboriginal schoolchildren aged 7-12 years living in remote areas in Pos Betau, Pahang, Malaysia to investigate the potential determinants influencing the cognitive function and educational achievement of these children. Cognitive function was measured by intelligence quotient (IQ), while examination scores of selected school subjects were used in assessing educational achievement. Blood samples were collected to assess serum Fe status. All children were screened for soil-transmitted helminthes. Demographic and socio-economic data were collected using pre-tested questionnaires. Almost two-thirds (67·6 %) of the subjects had poor IQ and most of them (72·6 %) had insufficient educational achievement. Output of the stepwise multiple regression model showed that poor IQ was significantly associated with low household income which contributed the most to the regression variance (r2 0·059; P = 0·020). Low maternal education was also identified as a significant predictor of low IQ scores (r2 0·042; P = 0·043). With educational achievement, Fe-deficiency anaemia (IDA) was the only variable to show significant association (r2 0·025; P = 0·015). In conclusion, the cognitive function and educational achievement of Aboriginal schoolchildren are poor and influenced by household income, maternal education and IDA. Thus, effective and integrated measures to improve the nutritional and socio-economic status of rural children would have a pronounced positive effect on their education.

  15. A decision-making tool to determine economic feasibility and break-even prices for artisan cheese operations.

    PubMed

    Durham, Catherine A; Bouma, Andrea; Meunier-Goddik, Lisbeth

    2015-12-01

    Artisan cheese makers lack access to valid economic data to help them evaluate business opportunities and make important business decisions such as determining cheese pricing structure. The objective of this study was to utilize an economic model to evaluate the net present value (NPV), internal rate of return, and payback period for artisan cheese production at different annual production volumes. The model was also used to determine the minimum retail price necessary to ensure positive NPV for 5 different cheese types produced at 4 different production volumes. Milk type, cheese yield, and aging time all affected variable costs. However, aged cheeses required additional investment for aging space (which needs to be larger for longer aging times), as did lower yield cheeses (by requiring larger-volume equipment for pasteurization and milk handling). As the volume of milk required increased, switching from vat pasteurization to high-temperature, short-time pasteurization was necessary for low-yield cheeses before being required for high-yield cheeses, which causes an additional increase in investment costs. Because of these differences, high-moisture, fresh cow milk cheeses can be sold for about half the price of hard, aged goat milk cheeses at the largest production volume or for about two-thirds the price at the lowest production volume examined. For example, for the given model assumptions, at an annual production of 13,608kg of cheese (30,000 lb), a fresh cow milk mozzarella should be sold at a minimum retail price of $27.29/kg ($12.38/lb), whereas a goat milk Gouda needs a minimum retail price of $49.54/kg ($22.47/lb). Artisan cheese makers should carefully evaluate annual production volumes. Although larger production volumes decrease average fixed cost and improve production efficiency, production can reach volumes where it becomes necessary to sell through distributors. Because distributors might pay as little as 35% of retail price, the retail price needs

  16. A cellular viability assay to monitor drug toxicity.

    PubMed

    Hansen, Jakob; Bross, Peter

    2010-01-01

    A central part of the research in protein misfolding and its associated disorders is the development of treatment strategies based on ensuring cellular protein homeostasis. This often includes testing chemical substances or drugs for their ability to counteract protein misfolding processes and to promote correct folding. Such investigations also include assessment of how the tested chemical substances affect cellular viability, that is, their cytotoxic effect. Investigations of cytotoxicity often require testing several different concentrations and drug exposure times using cells in culture. It is therefore attractive to use a viability test that permits the analysis of many samples with little handling time. This protocol describes a simple and fast methodology to analyze viability of lymphoblastoid cells and to test putative cytotoxic effects associated with exposure to a chemical substance, here exemplified by celastrol. The natural substance celastrol has been used for many years in traditional Chinese medicine and has subsequently been shown to induce transcription of genes encoding molecular chaperones (heat shock proteins) that are involved in promoting folding of cellular proteins. The well-described colorimetric tetrazolium salt (MTT) assay, which monitors metabolic activity of cultured cells, was adapted to analyze the viability of cells exposed to celastrol. After having established a suitable cell seeding density, the dose-dependence and time-course of viability reduction of lymphoblastoid cells treated with celastrol were determined. It was found that 4- and 24-h exposure to 0.8 microM celastrol reduced the viability of lymphoblastoid cells, with the most severe effect observed at 24 h with MTT reductions approaching 30% of non-exposed cells. For a series of incubations for 24 h, it was found that concentrations as low as 0.2 microM were sufficient to affect the viability, and celastrol concentrations of 0.5 microM reduced the MTT reduction rate to

  17. Comparison of reintroduction and enhancement effects on metapopulation viability

    USGS Publications Warehouse

    Halsey, Samniqueka J; Bell, Timothy J.; McEachern, Kathryn; Pavlovic, Noel B.

    2015-01-01

    Metapopulation viability depends upon a balance of extinction and colonization of local habitats by a species. Mechanisms that can affect this balance include physical characteristics related to natural processes (e.g. succession) as well as anthropogenic actions. Plant restorations can help to produce favorable metapopulation dynamics and consequently increase viability; however, to date no studies confirm this is true. Population viability analysis (PVA) allows for the use of empirical data to generate theoretical future projections in the form of median time to extinction and probability of extinction. In turn, PVAs can inform and aid the development of conservation, recovery, and management plans. Pitcher's thistle (Cirsium pitcheri) is a dune endemic that exhibited metapopulation dynamics. We projected viability of three natural and two restored populations with demographic data spanning 15–23 years to determine the degree the addition of reintroduced population affects metapopulation viability. The models were validated by comparing observed and projected abundances and adjusting parameters associated with demographic and environmental stochasticity to improve model performance. Our chosen model correctly predicted yearly population abundance for 60% of the population-years. Using that model, 50-year projections showed that the addition of reintroductions increases metapopulation viability. The reintroduction that simulated population performance in early-successional habitats had the maximum benefit. In situ enhancements of existing populations proved to be equally effective. This study shows that restorations can facilitate and improve metapopulation viability of species dependent on metapopulation dynamics for survival with long-term persistence of C. pitcheri in Indiana likely to depend on continued active management.

  18. Micro-organism and cell viability on antimicrobially modified titanium.

    PubMed

    Omori, S; Shibata, Y; Arimoto, T; Igarashi, T; Baba, K; Miyazaki, T

    2009-10-01

    When titanium is anodized by discharge in NaCl solution, both antimicrobial activity and osteoconductivity are conferred. The viability of adherent micro-organisms and cells on antimicrobial titanium remains uncertain. We hypothesized that a thin peroxidation barrier would efficiently destroy adherent bacteria, whereas adherent osteoblastic cells would be viable, since these cells adhere to the surface indirectly though serum proteins. The efficacy of antimicrobial titanium appears to be based on peroxidation, since peroxidation products were detected in parallel with the destruction of bacterial cell-surface structures. The peroxidation effect of antimicrobial titanium was confined to the surface within narrow limits. The viability of osteoblastic cells on the surface was strongly dependent on the presence of serum protein, whereas that of adherent Streptococcus mutans was not affected by the presence of serum proteins. Therefore, differences in the adherent systems used by bacteria and osteoblastic cells are important determinants of their viability on antimicrobial titanium.

  19. Relationship between humidity and influenza A viability in droplets and implications for influenza's seasonality.

    PubMed

    Yang, Wan; Elankumaran, Subbiah; Marr, Linsey C

    2012-01-01

    Humidity has been associated with influenza's seasonality, but the mechanisms underlying the relationship remain unclear. There is no consistent explanation for influenza's transmission patterns that applies to both temperate and tropical regions. This study aimed to determine the relationship between ambient humidity and viability of the influenza A virus (IAV) during transmission between hosts and to explain the mechanisms underlying it. We measured the viability of IAV in droplets consisting of various model media, chosen to isolate effects of salts and proteins found in respiratory fluid, and in human mucus, at relative humidities (RH) ranging from 17% to 100%. In all media and mucus, viability was highest when RH was either close to 100% or below ∼50%. When RH decreased from 84% to 50%, the relationship between viability and RH depended on droplet composition: viability decreased in saline solutions, did not change significantly in solutions supplemented with proteins, and increased dramatically in mucus. Additionally, viral decay increased linearly with salt concentration in saline solutions but not when they were supplemented with proteins. There appear to be three regimes of IAV viability in droplets, defined by humidity: physiological conditions (∼100% RH) with high viability, concentrated conditions (50% to near 100% RH) with lower viability depending on the composition of media, and dry conditions (<50% RH) with high viability. This paradigm could help resolve conflicting findings in the literature on the relationship between IAV viability in aerosols and humidity, and results in human mucus could help explain influenza's seasonality in different regions.

  20. Regionally Aligned Forces: Concept Viability and Implementation

    DTIC Science & Technology

    2015-03-01

    Carlisle Compendia of Collaborative Research United States Army War College Student Publications Regionally Aligned Forces: Concept Viability and...Concept Viability and Implementation 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER...Carlisle Compendia of Collaborative Research United States Army War College Student Publications Regionally Aligned Forces: Concept Viability and

  1. An efficient and economical MTT assay for determining the antioxidant activity of plant natural product extracts and pure compounds.

    PubMed

    Liu, Yunbao; Nair, Muraleedharan G

    2010-07-23

    Antioxidants scavenge free radicals, singlet oxygen, and electrons in cellular redox reactions. The yellow MTT [3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide] is reduced to a purple formazan by mitochondrial enzymes. NADPH is the basis of established in vitro cell viability assays. An antioxidant assay has been developed utilizing the redox reaction between MTT and selected natural product extracts and purified compounds. This simple, fast, and inexpensive MTT antioxidant assay is comparable with the lipid peroxidation inhibitory assay and can be mechanized to achieve high throughput.

  2. 26 CFR 53.4958-5 - Transaction in which the amount of the economic benefit is determined in whole or in part by the...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Transaction in which the amount of the economic benefit is determined in whole or in part by the revenues of one or more activities of the organization. 53.4958-5 Section 53.4958-5 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) MISCELLANEOUS EXCISE TAXES...

  3. Economics of wind farm layout

    SciTech Connect

    Germain, A.C.; Bain, D.A.

    1997-12-31

    The life cycle cost of energy (COE) is the primary determinant of the economic viability of a wind energy generation facility. The cost of wind turbines and associated hardware is counterbalanced by the energy which can be generated. This paper focuses on the turbine layout design process, considering the cost and energy capture implications of potential spacing options from the viewpoint of a practicing project designer. It is argued that lateral spacings in the range of 1.5 to 5 diameters are all potentially optimal, but only when matched to wind resource characteristics and machine design limits. The effect of wakes on energy capture is quantified while the effect on turbine life and maintenance cost is discussed qualitatively. Careful optimization can lower COE and project designers are encouraged to integrate the concepts in project designs.

  4. Ecological economics and economic growth.

    PubMed

    Victor, Peter A

    2010-01-01

    Boulding's 1966 paper on the economics of spaceship Earth established the framework for ecological economics and an understanding of economic growth. In ecological economics, economies are conceptualized as open subsystems of the closed biosphere and are subject to biophysical laws and constraints. Economic growth measured as an increase in real gross domestic product (GDP) has generally been associated with increases in the use of energy and materials and the generation of wastes. Scale, composition, and technology are the proximate determinants of environmental impacts. They are often reduced to two: scale (GDP) and intensity (impact per unit GDP). New work described in this paper defines "green" growth as intensity that declines faster than scale increases. Similarly, "brown" growth occurs when intensity declines more slowly than increases in scale, and "black" growth happens when both scale and intensity increase. These concepts are then related to the environmental Kuznets curve, which can be understood as a transition from brown to green growth. Ecological economics provides a macroperspective on economic growth. It offers broad policy principles, and it challenges the primacy of economic growth as a policy objective, but many important questions remain.

  5. Experiments with the Viability of Chicken Eggs

    ERIC Educational Resources Information Center

    Garigliano, Leonard J.

    1975-01-01

    Presents the results of an experiment designed to test two hypotheses: (1) a delay of two weeks at room temperature will have no effect on the viability of fertile chicken eggs and (2) refrigeration will have no effect on the viability of fertile chicken eggs. Experimenters were the author and two ninth-grade students. (PEB)

  6. Viability and infectivity of fresh and cryopreserved Nosema ceranae spores.

    PubMed

    McGowan, Janine; De la Mora, Alvaro; Goodwin, Paul H; Habash, Marc; Hamiduzzaman, Mollah Md; Kelly, Paul G; Guzman-Novoa, Ernesto

    2016-12-01

    The microsporidium fungus Nosema ceranae is an intracellular parasite that infects the midgut of the honey bee, Apis mellifera. A major limitation of research on N. ceranae is that the fungus is non-culturable and thus studying it depends on the seasonal availability of Nosema spores. Also, spore viability and infectivity can vary considerably, and thus there is a need for reliable methods for determining those traits. This study examined different conditions for N. ceranae spore cryopreservation at -70°C, assessing spore viability and infectivity. Viability was determined by a staining procedure counting total spores numbers with bright field microscopy and un-viable spore numbers with the fluorescent dye, propidium iodide. Spore infectivity was determined with a dilution inoculation assay. Infectivity was dependent on the inoculum dose for the proportion of bees with detectable Nosema infections based on the number of spores per bee at 18days after inoculation; 4000 spores per bee or higher were needed to get approx. 100% of the inoculated bees infected. The median infective dose (ID50) was 149 spores per bee, and the minimum dose capable of causing a detectable infection was 1.28 spores. The proportion of N. ceranae infected bees correlated significantly with the number of spores per bee (r=0.98, P<0.0001). N. ceranae spores cryopreserved in water or 10% glycerol did not differ in viability compared to fresh spores, but lost infectivity when inoculated into bees. This study shows that while cryopreservation of N. ceranae spores can preserve viability, the spores can have reduced infectivity.

  7. Determining the optimal nitrogen rate for summer maize in China by integrating agronomic, economic, and environmental aspects

    NASA Astrophysics Data System (ADS)

    Wang, G. L.; Ye, Y. L.; Chen, X. P.; Cui, Z. L.

    2014-06-01

    The concept of high yield with a goal of minimum environmental cost has become widely accepted. However, the trade-offs and complex linkages among agronomic, economic, and environmental factors are not yet well understood. In this study, reactive nitrogen (Nr) losses were estimated using an empirical model, and an economic indicator and an evaluation model were used to account for the environmental costs of N fertilizer production and use. The minimum N rate to achieve the maximum yield benefit (agronomically optimal N rate), maximum economic benefit (economically optimal N rate: economic benefit was defined as yield benefit minus N fertilizer cost), and maximum net benefit (ecologically optimal N rate: net benefit was defined as yield benefit minus N fertilizer and environmental costs) were estimated based on 91 on-farm experiment sites with five N levels for summer maize production on the North China Plain. Across all experimental sites, the agronomically, economically, and ecologically optimal N rates (Nagr, Neco, and Necl, respectively) averaged 289, 237, and 171 kg N ha-1, respectively. Necl management increased net benefit by 53% with a 46% decrease in total environmental costs, and a 51% decrease in Nr loss intensity from N fertilizer use (47, 65, and 38% for N2O emission, N leaching, and NH3 volatilization, respectively) and maintained grain yield, compared with Nagr management. Compared with Neco management, Necl increased net benefit by 12%, with a 31% decrease in total environmental costs and a 33% decrease in Nr loss intensity from N fertilizer use, and maintained economic benefit and grain yield. No differences in Necl were observed between soil types or years, but significant variation among counties was revealed. Necl increased with the increase in N-derived yield with an R2 of 0.83. In conclusion, Necl was primarily affected by N-derived yield and could enhance profitability as well as reduce Nr losses associated with the maize grain yield.

  8. Determining the optimal nitrogen rate for summer maize in China by integrating agronomic, economic, and environmental aspects

    NASA Astrophysics Data System (ADS)

    Wang, G. L.; Ye, Y. L.; Chen, X. P.; Cui, Z. L.

    2014-02-01

    The concept of high yield with a goal of minimum environmental cost has become widely accepted. However, the trade-offs and complex linkages among agronomic, economic, and environmental factors are not yet well understood. In this study, reactive nitrogen (Nr) losses were estimated using an empirical model, and an economic indicator and an evaluation model were used to account for the environmental costs of different Nr losses after N fertilizer application. The minimum N rate to achieve the maximum yield benefit (agronomically optimal N rate), maximum economic benefit (economically optimal N rate: economic benefit was defined as yield benefit minus N fertilizer cost), and maximum net benefit (ecologically optimal N rate: net benefit was defined as yield benefit minus N fertilizer and environmental costs) were estimated based on 91 on-farm experiment sites with five N levels for summer maize production on the North China Plain. Across all experimental sites, the agronomically, economically, and ecologically optimal N rates (Nagr, Neco, and Necl, respectively) averaged 289, 237, and 186 kg N ha-1, respectively. Necl management increased net benefit by 31% with a 45% decrease in Nr loss intensity (44%, 60%, and 33% for N2O emission, N leaching, and NH3 volatilization, respectively) and maintained grain yield, compared to Nagr management. Compared to Neco management, Necl increased net benefit by 6%, with a 27% decrease in Nr loss intensity, and maintained economic benefit and grain yield. No differences in Necl were observed between soil types or years, but significant variation among counties was revealed. Necl increased with the increase in N-derived yield with an R2 of 0.80. In conclusion, Necl was primarily affected by N-derived yield and could enhance profitability as well as reduce Nr losses associated with the maize grain yield.

  9. Spatial and Temporal Measurements of Temperature and Cell Viability in Response to Nanoparticle Mediated Photothermal Therapy

    SciTech Connect

    Whitney, Jon R; Rodgers, Amanda; Harvie, Erica; Carswell, William; Torti, Suzy; Puretzky, Alexander A; Rouleau, Christopher M; Geohegan, David B; Rylander, Christopher; Rylander, Nichole M

    2012-01-01

    Aim: Nanoparticle enhanced photothermal therapy is a promising alternative to tumor resection. However, quantitative measurements of cellular response to these treatments are limited. This paper introduces a Bimodal Enhanced Analysis of Spatiotemporal Temperature (BEAST) algorithm to rapidly determine the viability of cancer cells in vitro following photothermal therapy alone or in combination with nanoparticles. Materials & Methods: To illustrate the capability of the BEAST viability algorithm, single wall carbon nanohorns were added to renal cancer (RENCA) cells in vitro and time-dependent spatial temperature maps measured with an infrared camera during laser therapy were correlated with post-treatment cell viability distribution maps obtained by cell-staining fluorescent microscopy. Conclusion: The BEAST viability algorithm accurately and rapidly determined the cell viability as function of time, space, and temperature.

  10. An Assessment of the Effectiveness and Viability of Various Mitigation Technologies under Different Scenarios Using the PESERA-DESMICE Model

    NASA Astrophysics Data System (ADS)

    Nainggolan, D.; Fleskens, L.; Stringer, L. C.

    2012-04-01

    Scenario analysis of policy options is one of the most valuable ways in which scientific models can be employed to inform decision-making process. This is particularly relevant for land degradation mitigation policies, which are rarely based on this kind of analysis. In this paper we show how the PESERA-DESMICE modelling framework can be used in the assessment of policy options to combat land degradation, illustrating the model analysis of policy options with scenarios for different study sites. The key assumption underlying our analyses is that technologies must be attractive in economic terms, i.e. have the potential to, from a land user perspective, lead to cost reductions, benefit enhancements or both. Trade-off and cost-effectiveness thus form integral parts of the framework. The sequence of options is explored by: (1) Determining which technologies are feasible in which locations. This includes an assessment of economic viability for the land user in each location; we term these the technology scenarios; (2) Determining how policy instruments such as subsidies and credit can have the potential to influence upfront investment requirements and economic viability and how they lead to reduced levels of land degradation on the other; we term these the policy scenarios; (3) Determining how technology adoption affects development issues such as food production and livelihoods; we term these the global scenarios. All types of scenario were found to be useful to policymakers in different ways. Technology scenarios may help focus the portfolio of land degradation mitigation technologies towards areas in need of policy support; policy scenarios further detail the types and levels of support necessary for promoting adoption of the technology; while global scenarios demonstrate how the changes envisaged contribute to the achievement of wider sustainable development goals. Keywords: integrated environmental model, land degradation, mitigation technologies, scenario

  11. Determination of the Economic Viability & Technical Feasibility of Commercial Jatropha Curcas Production for Generation of Jatropha oil as Bio-Fuel Feedstock from Wasteland: Final Technical Report on Life Cycle Impact Assessment of Jatropha Cultivation

    SciTech Connect

    Ghosh, Arup; Chikara, Jitendra; Wheeler, Candace

    2012-12-01

    Ever since it was demonstrated that Jatropha seed oil could be converted into a world class biodiesel and could run in unmodified stationary and mobile diesel engines with simultaneous reduction in emissions, it caught the attention of the world. The capability to grow this crop on wastelands added to its attractiveness. However, the single biggest challenge came in the form of the availability of adequate feed stock in the form of the Jatropha fruit. Adequacy of feed stock can only be possible if large plantations are cultivated and produce enough fruit. The people, world over, jumped into Jatropha cultivation without heeding to the need to first ensure quality germplasm and understand the agronomic requirements of the plants. As a result many plantations failed to give the required yield. CSIR-CSMCRI had been researching Jatropha and had an end-to-end approach, i.e., it developed the best technology to prepare biodiesel and also worked towards the practical problems that it envisaged to be important for raising Jatropha productivity. It focused only on cultivation on wastelands as this was the only practical strategy, given the limited arable land India has and the risk of food security for the burgeoning population. While working in this direction, the Institute zeroed-in on a few germplasm, which gave consistently higher seed yield over several years. These germplasm were clonally propagated in large numbers to be raised in experimental plantations at different geographical locations in India. Many agronomic practices were developed as a part of these different projects. It was at this juncture that General Motors and the U.S. Department of Energy joined hands with CSIR-CSMCRI to further the work on Jatropha. A center of expertise for Jatropha was established and work was initiated to further refine the understanding regarding the best practices. Efforts were to be made to generate primary data, hitherto unavailable for wastelands, on which life cycle assessment studies were to be performed as a part of the project.

  12. A comparison of assays measuring the viability of Legionella ...

    EPA Pesticide Factsheets

    Background: The relatively high prevalence of Legionella pneumophila in premise plumbing systems has been widely reported. Published reports indicate Legionella has a comparatively high resistance to chlorine and moreover has the ability to grow in phagocytic amoeba which could provide additional protection in chlorinated drinking water distribution systems. Copper-Silver (Cu-Ag) ionization treatment systems are commercially available for use in large building water systems to help control the risks from Legionella bacteria. The objectives of this study were to develop and optimize Legionella viability assays and use them to investigate the viability of Legionella bacteria after exposure to water treated with coppper and silver ions. Methods: Log phase L. pneumophila cells were used in all experiments and were generated by incubation at 35C for 48 hours in buffered yeast extract broth. Viability assays used included plating on buffered charcoal yeast extract agar to determine the number of culturable cells and treating cells with propidium monoazide (PMA) or ethidium monoazide (EMA) followed by quantitative PCR targeting mip gene of L. pneumophila. The qPCR viability assays were optimized using L. pneumophila inactivated by heat treatment at 65C for 60 min. The effectiveness of Cu-Ag ionization treatment was studied by inoculating L. pneumonia at 105 CFU/mL in water collected directly from a building water system that employed this technology and incubat

  13. Economic Time Series Modeling to Determine the Feasibility of Incorporating Drinking Water Treatment in Water Quality Trading

    EPA Science Inventory

    The critical steps required to evaluating the feasiblity of establishing a water quality trading market in a testbed watershed is described. Focus is given toward describing the problem of thin markets as a specifi barrier to successful trading. Economic theory for considering an...

  14. Determining How Tertiary Education and Human Capital Formation Influenced Economic Expansion in Israel, Japan, and Norway from 2000-2010

    ERIC Educational Resources Information Center

    Kalkbrenner, Erin Lee

    2014-01-01

    Researchers have calculated the relationship between human capital development and economic output by various means of econometric modeling and by use of numerous indicators under the context of an assortment of human capital theory. This study was conducted to identify new interpretations of the expansion of human capital in the form of tertiary…

  15. A New Methodology for Evaluation of Nematode Viability

    PubMed Central

    Ferreira, Sebastião Rodrigo; Mendes, Tiago Antônio Oliveira; Bueno, Lilian Lacerda; de Araújo, Jackson Victor; Bartholomeu, Daniella Castanheira; Fujiwara, Ricardo Toshio

    2015-01-01

    Nematodes infections are responsible for debilitating conditions and economic losses in domestic animals as well as livestock and are considered an important public health problem due to the high prevalence in humans. The nematode resistance for drugs has been reported for livestock, highlighting the importance for development of new anthelmintic compounds. The aim of the current study was to apply and compare fluorimetric techniques using Sytox and propidium iodide for evaluating the viability of C. elegans larvae after treatment with anthelmintic drugs. These fluorescent markers were efficient to stain larvae treated with ivermectin and albendazole sulfoxide. We observed that densitometric values were proportional to the concentration of dead larvae stained with both markers. Furthermore, data on motility test presented an inverse correlation with fluorimetric data when ivermectin was used. Our results showed that lower concentrations of drugs were effective to interfere in the processes of cellular transport while higher drugs concentrations were necessary in order to result in any damage to cell integrity. The methodology described in this work might be useful for studies that aim to evaluate the viability of nematodes, particularly for testing of new anthelminthic compounds using an easy, economic, reproducible, and no time-consuming technique. PMID:25866820

  16. The mind and heart (literally) of the negotiator: personality and contextual determinants of experiential reactions and economic outcomes in negotiation.

    PubMed

    Dimotakis, Nikolaos; Conlon, Donald E; Ilies, Remus

    2012-01-01

    The authors developed and tested a model proposing that negotiator personality interacts with the negotiation situation to influence negotiation processes and outcomes. In 2 studies, the authors found that negotiators high in agreeableness were best suited to integrative negotiations and that negotiators low in agreeableness were best suited to distributive negotiations. Consistent with this person-situation fit argument, in Study 1 the authors found that negotiators whose dispositions were a good fit to their negotiation context had higher levels of physiological (cardiac) arousal at the end of the negotiation compared with negotiators who were "misplaced" in situations inconsistent with their level of agreeableness, and this arousal was in turn related to increased economic outcomes. Study 2 replicated and extended the findings of Study 1, finding that person-situation fit was related to physiological (heart rate), psychological (positive affect), and behavioral activation (persistence) demonstrated during the negotiation, and these measures in turn were related to the economic outcomes achieved by participants.

  17. Sperm storage and viability in Photinus fireflies.

    PubMed

    Demary, Kristian C

    2005-07-01

    In many species females mate with and store sperm from multiple males, and some female insects have evolved multiple compartments for sperm storage. Sperm storage and sperm viability were investigated in two firefly species, Photinus greeni and P. ignitus, which differ in the morphology of the female reproductive tract. Although the primary spermatheca is similar in both species, P. greeni females have an additional, conspicuous outpocketing within the bursa copulatrix whose potential role in sperm storage was investigated in this study. An assay that distinguishes between live and dead sperm was used to examine sperm viability in male seminal vesicles and sperm storage sites within the female reproductive tract. For both Photinus species, sperm from male seminal vesicles showed significantly higher viability compared to sperm from the primary spermatheca of single mated females. In single mated P. greeni females, sperm taken from the channel outpocketing (secondary spermatheca) showed significantly higher viability compared to sperm from the primary spermatheca. This sperm viability difference was not evident in double mated females. There were no significant differences between P. greeni and P. ignitus females in the viability of sperm from the primary spermatheca. These studies contribute to our understanding of post-mating processes that may influence paternity success, and suggest that sexual conflict over control of fertilizations may occur in multiply mated firefly females.

  18. The socioeconomic determinants of health: economic growth and health in the OECD countries during the last three decades.

    PubMed

    López-Casasnovas, Guillem; Soley-Bori, Marina

    2014-01-08

    In times of economic crisis, most countries face the dual challenge of fighting unemployment while restraining social expenditures and closing budget deficits. The spending cuts and lack of employment affect a large number of decisions that have a direct or indirect impact on health. This impact is likely to be unevenly distributed among different groups within the population, and therefore not only health levels may be at risk, but also their distribution. The main purpose of this paper is to explore links between unemployment, economic growth, inequality, and health. We regress a measure of health, the Health Human Development Index (HHDI), against a set of explanatory variables accounting for the countries' economic performance (GDP growth, unemployment, and income inequality), and some institutional factors related to welfare spending and the nature of the health systems for the past three decades. In addition, we explore the causes for different results obtained using an inequality-adjusted HHDI, vs. the unadjusted HHDI. We describe a panel data model, estimated by random effects, for 32 countries from 1980-2010, in five-year intervals. Our conclusion is that the high economic growth observed in the last decades, together with an increase in the levels of income inequality and/or poverty, explain the observed changes of our index, particularly when this indicator is weighted by health inequality. The remaining institutional variables (the share of social spending, health care expenditure, and the type of health systems) show the expected sign but are not statistically significant. A comment on the methodological pitfalls of the approach completes the analysis.

  19. Is Socio-Economic Status a Determinant of HIV-Related Stigma Attitudes in Zimbabwe? Findings from Project Accept

    PubMed Central

    Singh, Basant; Chingono, Alfred; Sibanda, E.; Machingura, Ian

    2016-01-01

    HIV related stigma and discrimination is a known barrier for HIV prevention and care. We aimed to assess the relationship between socio-economic status (SES) and HIV related stigma in Zimbabwe. This paper uses data from Project Accept, which examined the impact of community-based voluntary counseling and testing intervention on HIV incidence and stigma. Total of 2522 eligible participants responded to a psychometric assessment tool, which assessed HIV related stigma and discrimination attitudes on 4 point Likert scale. The tool measured three components of HIV-related stigma: shame, blame and social isolation, perceived discrimination, and equity. Participants’ ownership of basic assets was used to assess the socio-economic status. Shame, blame and social isolation component of HIV related stigma was found to be significantly associated with medium [odds ratio (OR)=1.73, P<0.01] and low SES (OR=1.97, P<0.01), indicating more stigmatizing attitudes by participants belonging to medium and low SES in comparison to high SES. For HIV related stigma and discrimination programs to be effective, they should take into account the socio-economic context of target population. PMID:28299151

  20. Is Socio-Economic Status a Determinant of HIV-Related Stigma Attitudes in Zimbabwe? Findings from Project Accept.

    PubMed

    Mateveke, Kudzanai; Singh, Basant; Chingono, Alfred; Sibanda, E; Machingura, Ian

    2016-08-17

    HIV related stigma and discrimination is a known barrier for HIV prevention and care. We aimed to assess the relationship between socio-economic status (SES) and HIV related stigma in Zimbabwe. This paper uses data from Project Accept, which examined the impact of community-based voluntary counseling and testing intervention on HIV incidence and stigma. Total of 2522 eligible participants responded to a psychometric assessment tool, which assessed HIV related stigma and discrimination attitudes on 4 point Likert scale. The tool measured three components of HIV-related stigma: shame, blame and social isolation, perceived discrimination, and equity. Participants' ownership of basic assets was used to assess the socio-economic status. Shame, blame and social isolation component of HIV related stigma was found to be significantly associated with medium [odds ratio (OR)=1.73, P<0.01] and low SES (OR=1.97, P<0.01), indicating more stigmatizing attitudes by participants belonging to medium and low SES in comparison to high SES. For HIV related stigma and discrimination programs to be effective, they should take into account the socio-economic context of target population.

  1. Influence of novel resin monomer on viability of L-929 mouse fibroblasts in vitro.

    PubMed

    Jinno, Satoshi; Kawai, Tatsushi; Ishikawa, Atsuko; Suzuki, Tomoo; Hattori, Nobuaki; Okeya, Hiroyuki; Hayashi, Tatsuhide; Maeda, Hatsuhiko; Ohno, Yuzo; Ito, Masamitsu; Noguchi, Toshihide

    2006-12-01

    We have previously synthesized a novel acrylic resin monomer, methacryloyloxyethyl methyl succinate (TA). The aim of this in vitro study, therefore, was to examine its influence on cell viability using L-929 mouse fibroblasts and then compare the results with MMA, EMA, and LMA. Medium containing each monomer was changed every 15 minutes as some monomers were volatile. After one hour of exposure, these mediums were replaced with a normal medium and cells were further incubated for 72 hours. IC50 value for each monomer was determined, and chronological cell viability and cytomorphologic observation were evaluated. Viability was impaired in a dose-dependent manner. All monomers, except TA, tended to correlate between molecular weight and cell viability. On the other hand, TA showed excellent viability and did not impair growth abruptly. These results thus demonstrated that cellular damage by TA was much lower than that by other monomers.

  2. Viability and Management Targets of Mediterranean Demersal Fisheries: The Case of the Aegean Sea

    PubMed Central

    Tserpes, George; Maravelias, Christos; Carvalho, Natacha; Merino, Gorka

    2016-01-01

    Management of the Mediterranean demersal stocks has proven challenging mainly due to the multi-species character of the fisheries. In the present work, we focus on the multi-species demersal fisheries of the Aegean Sea (eastern Mediterranean) aiming to study the effects of different management measures on the main commercial stocks, as well as to explore the economic viability of the fisheries depending upon these resources, by means of simulated projections. Utilizing the limited available data, our results demonstrated that, under the current exploitation pattern, the economic viability of the fleets is threatened, particularly if fuel prices increase. Additionally, the biological targets set for the most exploited species, such as hake, will not be met under the current management regime. The projections also showed that the only management scenario under which both resource sustainability and economic viability of the fisheries are ensured is the decrease of fleet capacity in terms of vessel numbers. In this case, however, measures to support the fisheries-dependent communities need to be implemented to prevent the collapse of local economies due to employment decrease. Scenarios assuming selectivity improvements would be also beneficial for the stocks but they showed low economic performance and their application would threaten the viability of the fleets, particularly that of the trawlers. PMID:28033348

  3. An Arabidopsis senescence-associated protein SAG29 regulates cell viability under high salinity.

    PubMed

    Seo, Pil Joon; Park, Jung-Min; Kang, Seok Ki; Kim, Sang-Gyu; Park, Chung-Mo

    2011-01-01

    The plasma membrane is an important cellular organ that perceives incoming developmental and environmental signals and integrates these signals into cellular regulatory mechanisms. It also acts as a barrier against unfavorable extracellular factors to maintain cell viability. Despite its importance for cell viability, molecular components determining cell viability and underlying mechanisms are largely unknown. Here, we show that a plasma membrane-localized MtN3 protein SAG29 regulates cell viability under high salinity in Arabidopsis. The SAG29 gene is expressed primarily in senescing plant tissues. It is induced by osmotic stresses via an abscisic acid-dependent pathway. Whereas the SAG29-overexpressing transgenic plants (35S:SAG29) exhibited an accelerated senescence and were hypersensitive to salt stress, the SAG29-deficient mutants were less sensitive to high salinity. Consistent with this, the 35S:SAG29 transgenic plants showed reduced cell viability in the roots under normal growth condition. In contrast, cell viability in the SAG29-deficient mutant roots was indistinguishable from that in the roots of control plants. Notably, the mutant roots exhibited enhanced cell viability under high salinity. Our observations indicate that the senescence-associated SAG29 protein is associated with cell viability under high salinity and other osmotic stress conditions. We propose that the SAG29 protein may serve as a molecular link that integrates environmental stress responses into senescing process.

  4. Economic Evaluation of Observatory Solar-Energy System

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Long-term economic performance of a commercial solar-energy system was analyzed and used to predict economic performance at four additional sites. Analysis described in report was done to demonstrate viability of design over a broad range of environmental/economic conditions. Topics covered are system description, study approach, economic analysis and system optimization.

  5. Socio-economic determinants in selecting childhood diarrhoea treatment options in Sub-Saharan Africa: A multilevel model

    PubMed Central

    2011-01-01

    Background Diarrhoea disease which has been attributed to poverty constitutes a major cause of morbidity and mortality in children aged five and below in most low-and-middle income countries. This study sought to examine the contribution of individual and neighbourhood socio-economic characteristics to caregiver's treatment choices for managing childhood diarrhoea at household level in sub-Saharan Africa. Methods Multilevel multinomial logistic regression analysis was applied to Demographic and Health Survey data conducted in 11 countries in sub-Saharan Africa. The unit of analysis were the 12,988 caregivers of children who were reported to have had diarrhoea two weeks prior to the survey period. Results There were variability in selecting treatment options based on several socioeconomic characteristics. Multilevel-multinomial regression analysis indicated that higher level of education of both the caregiver and that of the partner, as well as caregivers occupation were associated with selection of medical centre, pharmacies and home care as compared to no treatment. In contrast, caregiver's partners' occupation was negatively associated with selection medical centre and home care for managing diarrhoea. In addition, a low-level of neighbourhood socio-economic disadvantage was significantly associated with selection of both medical centre and pharmacy stores and medicine vendors. Conclusion In the light of the findings from this study, intervention aimed at improving on care seeking for managing diarrhoea episode and other childhood infectious disease should jointly consider the influence of both individual SEP and the level of economic development of the communities in which caregivers of these children resides. PMID:21429217

  6. Where health disparities begin: the role of social and economic determinants--and why current policies may make matters worse.

    PubMed

    Woolf, Steven H; Braveman, Paula

    2011-10-01

    Health disparities by racial or ethnic group or by income or education are only partly explained by disparities in medical care. Inadequate education and living conditions-ranging from low income to the unhealthy characteristics of neighborhoods and communities-can harm health through complex pathways. Meaningful progress in narrowing health disparities is unlikely without addressing these root causes. Policies on education, child care, jobs, community and economic revitalization, housing, transportation, and land use bear on these root causes and have implications for health and medical spending. A shortsighted political focus on reducing spending in these areas could actually increase medical costs by magnifying disease burden and widening health disparities.

  7. Historical notes on immaturity. Part 1: measures of viability.

    PubMed

    Obladen, Michael

    2011-09-01

    The interest in the limit of viability originated from various sources, including legal requirements, the rejection of mechnical life support, competition for resources, concerns about handicaps, and proximity to the fetus with its limited rights. Gestational age was determined from menstrual history by Hippocratic writers, who established the tenacious idea that 7-, but not 8-month infants could survive. Naegele's rule, already published by Boerhaave in 1744, was correct when applied to the last day of menstruation. Birth weight and length were not measured until the end of the 18(th) century. This remarkable disinterest resulted from superstition, grossly inaccurate measurements by the authorities Mauriceau and Smellie, and the conversion chaos of the pre-metric era. A table is provided with historic mass and length units allowing to determine birth weight and body length in the older literature. The idea of viability is a remnant of vitalism, a medical doctrine popularized in 1780 by Brown. Many short-lived statements defined its limit, but until now what was meant by viability remained nebulous.

  8. Economics of Distance Education Reconsidered

    ERIC Educational Resources Information Center

    Laaser, Wolfram

    2008-01-01

    According to Gartner a certain hype of e-Learning was followed by a downturn but eLearning will continue to be an important factor in learning scenarios. However the economic viability of e-learning projects will be questioned with more scrutiny than in earlier periods. Therefore it seems to be a good opportunity to see what can be learned from…

  9. Radiolabeled red cell viability. I. Comparison of /sup 51/Cr, /sup 99m/Tc, and /sup 111/In for measuring the viability of autologous stored red cells

    SciTech Connect

    Marcus, C.S.; Myhre, B.A.; Angulo, M.C.; Salk, R.D.; Essex, C.E.; Demianew, S.H.

    1987-09-01

    The simultaneous determination of autologous /sup 99m/Tc red cell (RBC) and /sup 51/Cr RBC viability at 24 hours was measured in 19 normal volunteers whose RBCs had been stored in additive media (Nutracel) for 42 or 49 days. The ratio of the /sup 51/Cr:/sup 99m/Tc value was 1.23. In this experiment we also calculated /sup 51/Cr RBC viability by both the single-isotope method (extrapolation) and the double-isotope method (using /sup 125/I human serum albumin for an independent plasma volume) in the same volunteers. The corresponding viability values were not significantly different. The simultaneous determination of autologous /sup 111/In-oxine RBC and /sup 51/Cr RBC viability at 24 hours was measured in 19 other normal volunteers whose RBCs had been stored in citrate-phosphate-dextrose-adenine (CPDA-1) for 1 or 15 days. The ratio of the /sup 51/Cr:/sup 111/In value was 1.1. Use of these 24-hour viability ratios as conversion factors permits direct comparison of /sup 99m/Tc or /sup 111/In RBC viability with a /sup 51/Cr standard, and therefore expands the application of these newer RBC radiolabels.

  10. Fiches pratiques: Le circuit de l'herbe; Journal a plusieurs mains; Comment aborder l'economie d'une facon economique; Des articles d'autrefois aux determinants d'aujourd'hui (Practical Ideas: The Path of Grass; Group Diary; Approaching Economics in an Economical Way; From Yesterday's Articles to Today's Determiners).

    ERIC Educational Resources Information Center

    Vever, Daniel; And Others

    1991-01-01

    Four activities for the French language classroom are described, including a comprehension game based on the cow's digestive system, a group journal exercise using current events, an economics vocabulary development activity, and a grammar exercise focusing on the use of determiners in news articles. (MSE)

  11. Poxvirus viability and signatures in historical relics.

    PubMed

    McCollum, Andrea M; Li, Yu; Wilkins, Kimberly; Karem, Kevin L; Davidson, Whitni B; Paddock, Christopher D; Reynolds, Mary G; Damon, Inger K

    2014-02-01

    Although it has been >30 years since the eradication of smallpox, the unearthing of well-preserved tissue material in which the virus may reside has called into question the viability of variola virus decades or centuries after its original occurrence. Experimental data to address the long-term stability and viability of the virus are limited. There are several instances of well-preserved corpses and tissues that have been examined for poxvirus viability and viral DNA. These historical specimens cause concern for potential exposures, and each situation should be approached cautiously and independently with the available information. Nevertheless, these specimens provide information on the history of a major disease and vaccination against it.

  12. Study of quiet turbofan STOL aircraft for short-haul transportation. Volume 5: Economics

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The economic aspects of the STOL aircraft for short-haul air transportation are discussed. The study emphasized the potential market, the preferred operational concepts, the design characteristics, and the economic viability. Three central issues governing economic viability are as follows: (1) operator economics given the market, (2) the required transportation facilities, and (3) the external economic effects of a set of regional STOL transportation systems.

  13. Metronidazole decreases viability of DLD-1 colorectal cancer cell line.

    PubMed

    Sadowska, Anna; Krętowski, Rafał; Szynaka, Beata; Cechowska-Pasko, Marzanna; Car, Halina

    2013-10-01

    The aim of our study was to evaluate the impact of metronidazole (MTZ) on DLD-1 colorectal cancer cell (CRC) line. Toxicity of MTZ was determined by MTT test. Cells were incubated with MTZ used in different concentrations for 24, 48, and 72 hours. The effect of MTZ on DNA synthesis was measured as [3H]-thymidine incorporation. The morphological changes in human DLD-1 cell line were defined by transmission electron microscope OPTON 900. The influence of MTZ on the apoptosis of DLD-1 cell lines was detected by flow cytometry and fluorescence microscopy, while cell concentration, volume, and diameter were displayed by Scepter Cell Counter from Millipore. Our results show that cell viability was diminished in all experimental groups in comparison with the control, and the differences were statistically significant. We did not find any significant differences in [3H]-thymidine incorporation in all experimental groups and times of observation. Cytofluorimetric assays demonstrated a statistically significant increase of apoptotic rate in MTZ concentrations 10 and 50 μg/mL after 24 hours; 0.1, 10, 50, and 250 μg/mL after 48 hours; and in all concentrations after 72 hours compared with control groups. In the ultrastructural studies, necrotic or apoptotic cells were occasionally seen. In conclusion, MTZ affects human CRC cell line viability. The reduction of cell viability was consistent with the apoptotic test.

  14. Reevaluating multicolor flow cytometry to assess microbial viability.

    PubMed

    Buysschaert, Benjamin; Byloos, Bo; Leys, Natalie; Van Houdt, Rob; Boon, Nico

    2016-11-01

    Flow cytometry is a rapid and quantitative method to determine bacterial viability. Although different stains can be used to establish viability, staining protocols are inconsistent and lack a general optimization approach. Very few "true" multicolor protocols, where dyes are combined in one sample, have been developed for microbiological applications. In this mini-review, the discrepancy between protocols for cell-permeant nucleic acid and functional stains are discussed as well as their use as viability dyes. Furthermore, optimization of staining protocols for a specific setup are described. Original data using the red-excitable SYTO dyes SYTO 59 to 64 and SYTO 17, combined with functional stains, for double and triple staining applications is also included. As each dye and dye combination behaves differently within a certain combination of medium matrix, microorganism, and instrument, protocols need to be tuned to obtain reproducible results. Therefore, single, double, and triple stains are reviewed, including the different parameters that influence staining such as stain kinetics, optimal stain concentration, and the effect of the chelator EDTA as membrane permeabilizer. In the last section, we highlight the need to investigate the stability of multicolor assays to ensure correct results as multiwell autoloaders are now commonly used.

  15. Viability and DNA fragmentation in differently sorted boar spermatozoa.

    PubMed

    De Ambrogi, M; Spinaci, M; Galeati, G; Tamanini, C

    2006-11-01

    Sperm cell defense against DNA damage relies on two factors: the tight packaging of chromatin, based on condensation and substitution of histones with protamines, and the antioxidant agents present in seminal plasma. These defenses are extremely important as mature sperm is unable to repair DNA damage and even if a successful fertilization occurs, embryo undergoes apoptosis at the time of genomic activation. Sex-sorting exposes spermatozoa to stress sources such as high pressure, laser beam and electrical charge. The aim of this work was to determine how sorting procedures affect viability and DNA integrity in boar spermatozoa, by using the newly developed Sperm-Sus-Halomax. Four sperm populations were considered: CONTROL (no treatment), REAL (sex-sorted semen), BULK (semen sorted without sex separation) and NO LASER (semen only exposed to the high pressure, but including also cells normally discarded from sex-sorting). A significantly (P=0.019) lower viability in NO LASER (64.71%) than in CONTROL (78.6%) and REAL (80.5%) groups was found; this was accompanied by a significantly (P=0.001) higher DNA fragmentation index (DFI) in NO LASER group (6.86%) respect to CONTROL (3.30%) and REAL (3.42%) groups. BULK group did not show any difference in viability or DFI as compared to the other groups. In conclusion, we may believe that sex-sorting procedure as a whole does not affect either viability or DFI and that shear mechanical forces are a relevant source of DNA damage for sorted semen.

  16. Effects of Fluid Shear Stress on Cancer Stem Cell Viability

    NASA Astrophysics Data System (ADS)

    Sunday, Brittney; Triantafillu, Ursula; Domier, Ria; Kim, Yonghyun

    2014-11-01

    Cancer stem cells (CSCs), which are believed to be the source of tumor formation, are exposed to fluid shear stress as a result of blood flow within the blood vessels. It was theorized that CSCs would be less susceptible to cell death than non-CSCs after both types of cell were exposed to a fluid shear stress, and that higher levels of fluid shear stress would result in lower levels of cell viability for both cell types. To test this hypothesis, U87 glioblastoma cells were cultured adherently (containing smaller populations of CSCs) and spherically (containing larger populations of CSCs). They were exposed to fluid shear stress in a simulated blood flow through a 125-micrometer diameter polyetheretherketone (PEEK) tubing using a syringe pump. After exposure, cell viability data was collected using a BioRad TC20 Automated Cell Counter. Each cell type was tested at three physiological shear stress values: 5, 20, and 60 dynes per centimeter squared. In general, it was found that the CSC-enriched U87 sphere cells had higher cell viability than the CSC-depleted U87 adherent cancer cells. Interestingly, it was also observed that the cell viability was not negatively affected by the higher fluid shear stress values in the tested range. In future follow-up studies, higher shear stresses will be tested. Furthermore, CSCs from different tumor origins (e.g. breast tumor, prostate tumor) will be tested to determine cell-specific shear sensitivity. National Science Foundation Grant #1358991 supported the first author as an REU student.

  17. The role of natural resource and environmental economics in determining the trade-offs in consumption and production of energy inputs: The case of biomass energy crops

    SciTech Connect

    Downing, M.; Graham, R.L.

    1993-12-31

    Natural resource economics issues deal with flows and funds of renewable and nonrenewable resources over time. These issues include topics concerned with management of fisheries, forests, mineral, energy resources, the extinction of species and the irreversibility of development over time. Environmental economics issues deal with regulation of polluting activities and the valuation of environmental amenities. In this study we outline a framework for studying both natural resource and environmental economics issues for any renewable or nonrenewable resource. Valuation from both the cost and benefit sides are addressed as they relate to the valuation of environmental programs or policies. By using this top-down approach to analyze and determine the costs and benefits of using renewable or nonrenewable resources, policy-makers on the global, national and local scales may be better informed as to the probable nonmarket and market ramifications of their natural resource and environmental policy decisions. This general framework for analysis is then focused to address biomass energy crops and their usage as inputs to energy production. As with any energy technology, a complete analysis must include an examination of the entire fuel cycle; specifically both production and consumption sides. From a production standpoint, market valuation issues such as crop management techniques, inputs to production, and community economics issues must be addressed as well as nonmarket valuation issues such as soil erosion, ground water effects and carbon sequestration. On the consumption side, market valuation considerations such as energy fuel efficiency and quality, cost of conversion and employment of labor are important factors while the critical nonmarket valuation factors are ambient air visibility, greenhouse gas release, and disposal of the by-products of conversion and combustion.

  18. Viability of nonminimally coupled f (R) gravity

    NASA Astrophysics Data System (ADS)

    Bertolami, Orfeu; Páramos, Jorge

    2016-03-01

    In this work we explore the viability of nonminimally coupled matter-curvature gravity theories, namely the conditions required for the absence of tachyon instabilities and ghost degrees of freedom. We contrast our finds with recent claims of a pathological behaviour of this class of models, which resorted to, in our view, an incorrect analogy with k-essence.

  19. Observability in strategic models of viability selection.

    PubMed

    Gámez, M; Carreño, R; Kósa, A; Varga, Z

    2003-10-01

    Strategic models of frequency-dependent viability selection, in terms of mathematical systems theory, are considered as a dynamic observation system. Using a general sufficient condition for observability of nonlinear systems with invariant manifold, it is studied whether, observing certain phenotypic characteristics of the population, the development of its genetic state can be recovered, at least near equilibrium.

  20. Viability of mesenchymal stem cells during electrospinning

    PubMed Central

    Zanatta, G.; Steffens, D.; Braghirolli, D.I.; Fernandes, R.A.; Netto, C.A.; Pranke, P.

    2011-01-01

    Tissue engineering is a technique by which a live tissue can be re-constructed and one of its main goals is to associate cells with biomaterials. Electrospinning is a technique that facilitates the production of nanofibers and is commonly used to develop fibrous scaffolds to be used in tissue engineering. In the present study, a different approach for cell incorporation into fibrous scaffolds was tested. Mesenchymal stem cells were extracted from the wall of the umbilical cord and mononuclear cells from umbilical cord blood. Cells were re-suspended in a 10% polyvinyl alcohol solution and subjected to electrospinning for 30 min under a voltage of 21 kV. Cell viability was assessed before and after the procedure by exclusion of dead cells using trypan blue staining. Fiber diameter was observed by scanning electron microscopy and the presence of cells within the scaffolds was analyzed by confocal laser scanning microscopy. After electrospinning, the viability of mesenchymal stem cells was reduced from 88 to 19.6% and the viability of mononuclear cells from 99 to 8.38%. The loss of viability was possibly due to the high viscosity of the polymer solution, which reduced the access to nutrients associated with electric and mechanical stress during electrospinning. These results suggest that the incorporation of cells during fiber formation by electrospinning is a viable process that needs more investigation in order to find ways to protect cells from damage. PMID:22183245

  1. Fetal pain, abortion, viability, and the Constitution.

    PubMed

    Cohen, I Glenn; Sayeed, Sadath

    2011-01-01

    In early 2010, the Nebraska state legislature passed a new abortion restricting law asserting a new, compelling state interest in preventing fetal pain. In this article, we review existing constitutional abortion doctrine and note difficulties presented by persistent legal attention to a socially derived viability construct. We then offer a substantive biological, ethical, and legal critique of the new fetal pain rationale.

  2. Development and validation of a multilateral index to determine economic status in developing countries: the Patient Financial Eligibility Tool (PFET).

    PubMed

    Saba, Joseph; Audureau, Etienne; Bizé, Marion; Koloshuk, Barbara; Ladner, Joël

    2013-04-01

    The objective was to develop and validate a multilateral index to determine patient ability to pay for medication in low- and middle-income countries. Primary data were collected in 2009 from 117 cancer patients in China, India, Thailand, and Malaysia. The initial tool included income, expenditures, and assets-based items using ad hoc determined brackets. Principal components analysis was performed to determine final weights. Agreement (Kappa) was measured between results from the final tool and from an Impact Survey (IS) conducted after beginning drug therapy to quantify a patient's actual ability to pay in terms of number of drug cycles per year. The authors present the step-by-step methodology employed to develop the tool on a country-by-country basis. Overall Cronbach value was 0.84. Agreement between the Patient Financial Eligibility Tool (PFET) and IS was perfect (equal number of drug cycles) for 58.1% of patients, fair (1 cycle difference) for 29.1%, and poor (>1 cycle) for 12.8%. Overall Kappa was 0.76 (P<0.0001). The PFET is an effective tool for determining an individual's ability to pay for medication. Combined with tiered models for patient participation in the cost of medication, it could help to increase access to high-priced products in developing countries.

  3. From Ideas to Development: The Determinants of R&D and Patenting. OECD Economics Department Working Papers, No. 457

    ERIC Educational Resources Information Center

    Jaumotte, Florence; Pain, Nigel

    2005-01-01

    This paper uses panel regressions to investigate the effects of innovation policies and framework factors on business R&D intensity and patenting for a sample of 20 OECD countries over the period 1982- 2001. Both sets of factors are found to matter; the main determinants of innovativeness appear to be the availability of scientists and engineers,…

  4. The xCELLigence system for real-time and label-free monitoring of cell viability.

    PubMed

    Ke, Ning; Wang, Xiaobo; Xu, Xiao; Abassi, Yama A

    2011-01-01

    We describe here the use of the xCELLigence system for label-free and real-time monitoring of cell -viability. The xCELLigence system uses specially designed microtiter plates containing interdigitated gold microelectrodes to noninvasively monitor the viability of cultured cells using electrical impedance as the readout. The continuous monitoring of cell viability by the xCELLigence system makes it possible to distinguish between different perturbations of cell viability, such as senescence, cell toxicity (cell death), and reduced proliferation (cell cycle arrest). In addition, the time resolution of the xCELLigence system allows for the determination of optimal time points to perform standard cell viability assays as well as other end-point assays to understand the mode of action. We have used the WST-1 assay (end-point viability readout), the cell index determination (continuous monitoring of viability by xCELLigence), and the DNA fragmentation assay (end-point apoptosis assay) to systematically examine cytotoxic effects triggered by two cytotoxic compounds with different cell-killing kinetics. Good correlation was observed for viability readouts between WST-1 and cell index. The significance of time resolution by xCELLigence readout is exemplified by its ability to pinpoint the optimal time points for conducting end point viability and apoptosis assays.

  5. Viability of bacteria in unused air filter media

    NASA Astrophysics Data System (ADS)

    Maus, R.; Goppelsröder, A.; Umhauer, H.

    Different experimental techniques were applied to determine the effects of different air filter media on the viability of bacteria. Rinse suspensions of unused filter media were employed in standard inhibition tests to determine the effects of filter ingredients on bacterial growth under ideal nutritional conditions. Furthermore, a new test procedure was proposed and validated to determine the survival of viable microorganisms in fibrous air filters as a function of different parameters. Samples of filter media were challenged with microbial aerosols in an experimental set-up designed for measuring the collection efficiencies of fibrous filters. The loaded filter samples were then challenged with clean air under controlled conditions for a definite time span and numbers of viable microorganisms in the filter media were determined as colony forming units. The filter samples were retrieved from unused filter media usually employed in common air conditioning and ventilation systems. Under ideal nutritional and moisture conditions, growth of investigated microorganisms in nutrient broth and on nutrient agar was not inhibited by the inclusion of filter samples or rinse solutions of different filters in the growth medium with one exception. M. luteus and E. coli collected in air filter media and exposed to low air humidity (RH = 30-60%) showed a decline in their viability as a function of time (within 1 h). The decline rate was dependent on the type of bacteria employed and also the filter material itself.

  6. Socio-economic determinants of child labour and attitudes to child labour among school children in Ibadan.

    PubMed

    Omokhodion, F O; Omokhodion, S I

    2004-12-01

    This cross sectional study was designed to compare the characteristics of working and non-working school children. Two hundred and thirty one working and 236 non-working children were interviewed. The socio economic factors associated with child labour were trading as mother's occupation, father's educational status, religion, family type (monogamous vs polygamous) and type of residence. Family type (OR = 0.562, 95% C.I. 0.353-0.897, p = 0.016), religion (OR = 0.559, 95% C.I. 0.361-0.867, p = 0.009) and trading as mother's occupation (O.R = 2.49, 95% CI 1.68-3.68, p = 0.000) were sustained on logistic regression analysis. With regard to attitude to child work, 186 (40%) of all respondents thought that children should be allowed to work. The majority of those who held this opinion 150, were child workers. Ten percent of working children had themselves chosen to work without any parental influence to do so. Seventy five respondents had ever repeated a class. Forty nine of these were working children a prevalence of 21% of repeaters compared to 26 non working children, (11%.) p = 0.004. Sixty eight percent of children aspiring to careers in artisan trades were child workers. Road traffic accidents and poor school performance were the commonest adverse effects of child labour indicated by school children. Parents should be educated about the adverse effects of child labour on child development. As poverty is one of the major root causes of child labour, free and compulsory primary education may help to reduce the notion of child work as an option for survival in poor families.

  7. Factors determining the viability of radiation processing in developing countries

    NASA Astrophysics Data System (ADS)

    van der Linde, HJ; Basson, RA

    In the fifteen years since the introduction of radiation processing to South Africa, four commercial irradiation facilities have been established. These are involved in the processing of a large variety of products, from syringes and prostheses to strawberries and sugar yeast. Three of the facilities are devoted mainly to food irradiation and several thousand tonnes are now processed annually. During this period it was repeatedly experienced that the successful introduction of radiation processing in general, and food radurization in particular, on a commercial scale was critically dependent on the following factors: acceptance by the producer, industry and consumer; initial capital expenditure; running costs and overheads in general; and continous throughput. All of these factors contribute to the processing cost which is the ultimate factor in determing the value/price ratio for the potential entrepreneur and customer of this new technology. After a market survey had identified the need for a new food irradiation facility to cope with the growing interest in commercial food radurization in the Western Cape, the above-mentioned factors were of cardinal importance in the design and manufacture of a new irradiator. The resulting batch-pallet facility which was commisioned in August 1986, is rather inefficient as far as energy utilization is concerned but this shortcoming is compensated for by its low cost, versatility and low hold-up. Although the facility has limitations as far as the processing of really large volumes of produce is concerned, it is particularly suitable not only for developing countries, but for developed countries in the introductory phase of commercial food radurization.

  8. Understanding Child Stunting in India: A Comprehensive Analysis of Socio-Economic, Nutritional and Environmental Determinants Using Additive Quantile Regression

    PubMed Central

    Fenske, Nora; Burns, Jacob; Hothorn, Torsten; Rehfuess, Eva A.

    2013-01-01

    Background Most attempts to address undernutrition, responsible for one third of global child deaths, have fallen behind expectations. This suggests that the assumptions underlying current modelling and intervention practices should be revisited. Objective We undertook a comprehensive analysis of the determinants of child stunting in India, and explored whether the established focus on linear effects of single risks is appropriate. Design Using cross-sectional data for children aged 0–24 months from the Indian National Family Health Survey for 2005/2006, we populated an evidence-based diagram of immediate, intermediate and underlying determinants of stunting. We modelled linear, non-linear, spatial and age-varying effects of these determinants using additive quantile regression for four quantiles of the Z-score of standardized height-for-age and logistic regression for stunting and severe stunting. Results At least one variable within each of eleven groups of determinants was significantly associated with height-for-age in the 35% Z-score quantile regression. The non-modifiable risk factors child age and sex, and the protective factors household wealth, maternal education and BMI showed the largest effects. Being a twin or multiple birth was associated with dramatically decreased height-for-age. Maternal age, maternal BMI, birth order and number of antenatal visits influenced child stunting in non-linear ways. Findings across the four quantile and two logistic regression models were largely comparable. Conclusions Our analysis confirms the multifactorial nature of child stunting. It emphasizes the need to pursue a systems-based approach and to consider non-linear effects, and suggests that differential effects across the height-for-age distribution do not play a major role. PMID:24223839

  9. Multimodality imaging for assessment of myocardial viability: nuclear, echocardiography, MR, and CT.

    PubMed

    Arrighi, James A; Dilsizian, Vasken

    2012-04-01

    The assessment of myocardial viability may be an important component of the evaluation of patients with coronary artery disease and left ventricular dysfunction. The primary goal of viability assessment in such patients is to guide therapeutic decisions by determining which patients would most likely benefit from revascularization. In patients with chronic coronary artery disease, left ventricular dysfunction may be a consequence of prior myocardium infarction, which is an irreversible condition, or reversible ischemic states such as stunning and hibernation. Imaging techniques utilize several methods to assess myocardial viability: left ventricular function, morphology, perfusion, and metabolism. Each technique (echocardiography, nuclear imaging, magnetic resonance imaging, and x-ray computed tomography) has the ability to assess one or more of these parameters. This article describes how each of these imaging modalities can be used to assess myocardial viability, and reviews the relative strengths and limitations of each technique.

  10. Infrared signatures to discriminate viability of autoclaved Bacillus spores

    NASA Astrophysics Data System (ADS)

    Schneider, Matthew D. W.; Valentine, Nancy B.; Johnson, Timothy J.

    2011-11-01

    Optical methods can offer good sensitivity for detecting small amounts of chemicals and biologicals, and as these methods mature, are some of the few techniques that can offer true standoff detection. For detection of biological species, determining the viability is clearly important: Certain species of gram-positive bacteria are capable of forming endospores, specialized structures that arise when living conditions become unfavorable or little growth medium is available. Spores are also resistant to many chemicals as well as changes in heat or pH; such spores can remain dormant from months to years until more favorable conditions arise, resulting in germination back to the vegetative state. This persistence characteristic of bacterial spores allows for contamination of a surface (e.g. food or medical equipment) even after the surface has been nominally cleaned. Bacterial spores have also been used as biological weapons, as in the case of B. anthracis. Thus, having rapid analytical methods to determine a spore's viability after attempts to clean a given environment is crucial. The increasing availability of portable spectrometers may provide a key to such rapid onsite analysis. The present study was designed to determine whether infrared spectroscopy may be used to differentiate between viable vs. dead B. subtilis and B. atrophaeus spores. Preliminary results show that the reproducible differences in the IR signatures can be used to identify the viable vs. the autoclaved (dead) spores.

  11. Infrared Signatures to Discriminate Viability of Autoclaved Bacillus Spores

    SciTech Connect

    Schneider, Matthew D.; Valentine, Nancy B.; Johnson, Timothy J.

    2011-10-06

    Optical methods can offer good sensitivity for detecting small amounts of chemicals and biologicals, and as these methods mature, are some of the few techniques that can offer true standoff detection. For detection of biological species, determining the viability is clearly important: Certain species of gram-positive bacteria are capable of forming endospores, specialized structures that arise when living conditions become unfavorable or little growth medium is available, being resistant to many chemicals as well as changes in heat or pH. Such spores can remain dormant from months to years until more favorable conditions arise, resulting in germination back to the vegetative state. This persistence characteristic of bacterial spores allows for contamination of a surface (e.g. food or medical equipment) even after the surface has been nominally cleaned. Bacterial spores have also been used as biological weapons, as in the case with B. anthracis. Thus, rapid analysis to determine a spore's viability in a given environment or after attempts to sterilize a given environment is crucial. The increasing availability of portable spectrometers may provide a key to such rapid onsite analysis. The present study was designed to determine whether infrared spectroscopy may be used to differentiate between viable vs. dead B. subtilis and B. atrophaeus spores. Preliminary results show that the reproducible differences in the IR signatures can be used to identify viable vs. autoclaved (dead) B. subtilis and B. atrophaeus bacterial spores.

  12. High-throughput viability assay using an autonomously bioluminescent cell line with a bacterial Lux reporter.

    PubMed

    Class, Bradley; Thorne, Natasha; Aguisanda, Francis; Southall, Noel; McKew, John C; Zheng, Wei

    2015-04-01

    Cell viability assays are extensively used to determine cell health, evaluate growth conditions, and assess compound cytotoxicity. Most existing assays are endpoint assays, in which data are collected at one time point after termination of the experiment. The time point at which toxicity of a compound is evident, however, depends on the mechanism of that compound. An ideal cell viability assay allows the determination of compound toxicity kinetically without having to terminate the assay prematurely. We optimized and validated a reagent-addition-free cell viability assay using an autoluminescent HEK293 cell line that stably expresses bacterial luciferase and all substrates necessary for bioluminescence. This cell viability assay can be used for real-time, long-term measurement of compound cytotoxicity in live cells with a signal-to-basal ratio of 20- to 200-fold and Z-factors of ~0.6 after 24-, 48- 72-, or 96-h incubation with compound. We also found that the potencies of nine cytotoxic compounds correlated well with those measured by four other commonly used cell viability assays. The results demonstrated that this kinetic cell viability assay using the HEK293(lux) autoluminescent cell line is useful for high-throughput evaluation of compound cytotoxicity.

  13. Linking Conservation Actions with Population Viability Models: Reducing Uncertainty to Better Predict Management Effects on Viability

    DTIC Science & Technology

    2011-05-01

    editors. Population viability analysis. University of Chicago Press, Chicago , Illinois, USA. Goodman, L. A. 1971. On the sensitivity of the...stochastic simulation of the extinction process. Version 9.71. Chicago Zoological Society, Brookfield, Illinois. Ladd, C., and L. Gass. 1999...Pages 511-520 in S.R. Beissinger and D.R. McCullough, editors. Population viability analysis. University of Chicago Press, Chicago , Illinois, USA

  14. Non-disruptive measurement system of cell viability in bioreactors

    NASA Astrophysics Data System (ADS)

    Rudek, F.; Nelsen, B. L.; Baselt, T.; Berger, T.; Wiele, M.; Prade, I.; Hartmann, P.

    2016-04-01

    Nutrient and oxygen transport, as well as the removal of metabolic waste are essential processes to support and maintain viable tissue. Current bioreactor technology used to grow tissue cultures in vitro has a fundamental limit to the thickness of tissues. Based on the low diffusion limit of oxygen a maximum tissue thickness of 200 μm is possible. The efficiency of those systems is currently under investigation. During the cultivation process of the artificial tissue in bioreactors, which lasts 28 days or longer, there are no possibilities to investigate the viability of cells. This work is designed to determine the influence of a non-disruptive cell viability measuring system on cellular activity. The measuring system uses a natural cellular marker produced during normal metabolic activity. Nicotinamide adenine dinucleotide (NADH) is a coenzyme naturally consumed and produced during cellular metabolic processes and has thoroughly been studied to determine the metabolic state of a cell. Measuring the fluorescence of NADH within the cell represents a non-disruptive marker for cell viability. Since the measurement process is optical in nature, NADH fluorescence also provides a pathway for sampling at different measurement depths within a given tissue sample. The measurement system we are using utilizes a special UV light source, to excite the NADH fluorescence state. However, the high energy potentially alters or harms the cells. To investigate the influence of the excitation signal, the cells were irradiated with a laser operating at a wavelength of 355 nm and examined for cytotoxic effects. The aim of this study was to develop a non-cytotoxic system that is applicable for large-scale operations during drug-tissue interaction testing.

  15. The cybernetics of viability: an overview

    NASA Astrophysics Data System (ADS)

    Nechansky, Helmut

    2011-10-01

    A three-level approach to viability is developed, considering (1) living systems, (2) a niche, understood as the area within the reach of their actions, and (3) an environment. A systematic analysis of the interrelations between these levels shows that living systems emerge with matter/energy processing systems. These can add controller structures when producing excess energy. A three-sensor controller structure enables a living system to deal with unfavourable and scarce environments. Further evolution of these controller structures offers improved ways to act on niches. Maintaining niches in scarce environments can require technology or economy. So social systems emerge, which are understood as aggregates of living systems. Basic patterns of interactions within social systems are analysed. So the introduction of the notion of the niche into the discussion of viability allows us to explain phenomena ranging from properties of single living systems to societal organization.

  16. Solar energy system economic evaluation for IBM system 1B, Carlsbad, New Mexico

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The economic performance of an operational test site of a solar energy system is described. The viability of the system was tested over a broad range of environmental and economic conditions. Significant results are reported.

  17. Hospital Viability during a Pandemic Influenza Outbreak

    DTIC Science & Technology

    2009-06-01

    provide protection from the next pandemic. 15. SUBJECT TERMS Hospital Security, Pandemic Influenza , Viability Checklist, 1918 Spanish Flu, 2003 SARS...pandemic influenza : 1918 Spanish Flu, 1957 Asian Flu, 1968 Hong Kong Flu, 2003 SARS epidemic, and 2005 Hurricane Katrina. Understanding the...emergency management events: 1918 , Spanish flu (H1N1); 2003, SARS outbreak; 2005, Hurricane Katrina, and the 2009, Swine flu (H1N1) outbreak, for the

  18. [Health Impact Assessments (HIA): an intersectoral process for action on the social, economic and environmental determinants of health].

    PubMed

    Saint-Pierre, Louise; Lamarre, Marie-Claude; Simos, Jean

    2014-03-01

    Health Impact Assessment (HIA) is a practice that has grown in popularity worldwide, since the end of the 1990s. Originally used in the framework of Environmental Impact Assessments (EIAs), HIA has become enriched through the addition of knowledge and principles based on the social determinants of health and the tackling of health inequalities, and has been brought to bear on the policy-planning process at all levels of government. HIA has three overlapping objectives: to assess the potential effects of a policy on health, to encourage citizen and stakeholder participation in the impact analysis process, and to inform the decision-making process. This article briefly defines HIA; defines its standardized process in successive steps, which allows users to give structure to their actions and to establish the steps to be followed (detection, framing, analysis, recommendations and evaluation); and offers three examples of HIA in three different situations: the Geneva canton of Switzerland; Rennes, France; and in the Montérégie region of Quebec, Canada. Together, these illustrations show that HIA is a promising strategy to influence local decisions and to integrate health into projects and policies at the local and regional levels.

  19. Positron Emission Tomography for the Assessment of Myocardial Viability

    PubMed Central

    2005-01-01

    Executive Summary Objective The objective was to update the 2001 systematic review conducted by the Institute For Clinical Evaluative Sciences (ICES) on the use of positron emission tomography (PET) in assessing myocardial viability. The update consisted of a review and analysis of the research evidence published since the 2001 ICES review to determine the effectiveness and cost-effectiveness of PET in detecting left ventricular (LV) viability and predicting patient outcomes after revascularization in comparison with other noninvasive techniques. Background Left Ventricular Viability Heart failure is a complex syndrome that impairs the contractile ability of the heart to maintain adequate blood circulation, resulting in poor functional capacity and increased risk of morbidity and mortality. It is the leading cause of hospitalization in elderly Canadians. In more than two-thirds of cases, heart failure is secondary to coronary heart disease. It has been shown that dysfunctional myocardium resulting from coronary heart disease (CAD) may recover contractile function (i.e. considered viable). Dysfunctional but viable myocardium may have been stunned by a brief episode of ischemia, followed by restoration of perfusion, and may regain function spontaneously. It is believed that repetitive stunning results in hibernating myocardium that will only regain contractile function upon revascularization. For people with CAD and severe LV dysfunction (left ventricular ejection fraction [LVEF] <35%) refractory to medical therapy, coronary artery bypass and heart transplantation are the only treatment options. The opportunity for a heart transplant is limited by scarcityof donor hearts. Coronary artery bypass in these patients is associated with high perioperative complications; however, there is evidence that revascularization in the presence of dysfunctional but viable myocardium is associated with survival benefits and lower rates of cardiac events. The assessment of left

  20. Finding the economics in economic entomology.

    PubMed

    Onstad, David W; Knolhoff, Lisa M

    2009-02-01

    To recommend new pest management tactics and strategies to farmers and policy makers, economic entomologists must evaluate the economics of biologically reasonable approaches. We collected data to determine how frequently these economic evaluations occur. We discovered from our survey of entomological journals representing the discipline of economic entomology that < 1% of research papers published since 1972 include economic evaluations of pest management tactics. At least 85% of these analyses were performed by entomologists and not economists. Much of the research on economic evaluations is performed without special funds granted by agencies separate from the authors' institutions. In the United States, USDA competitive grants supported 20% of the economic evaluations published since 2000. However, only approximately 12% of the projects funded since 2000 by three sections of the USDA (Crops at Risk, Risk Avoidance and Mitigation Program, and Pest Management Alternatives Program) resulted in publications concerning economic evaluations. If the purpose of economic entomology is to ultimately determine the value of different kinds of tactics, the discipline may need to take steps to enhance the research that supports these evaluations.

  1. Agricultural Modernization and Economic Inequality: The Indian Experience

    ERIC Educational Resources Information Center

    Michie, Aruna Nayyar

    1978-01-01

    Argues that agriculture production in developing nations should be organized to ensure economic viability. Government policy must emphasize participants' productive capacities and integrate agricultural workers into the new organization of production. (Author/DB)

  2. Nuclear hydrogen : an assessment of product flexibility and market viability.

    SciTech Connect

    Botterud, A.; Yildiz, B.; Conzelmann, G.; Petri, M.; Massachusetts Inst. of Tech.

    2008-01-01

    Nuclear energy has the potential to play an important role in the future energy system as a large-scale source of hydrogen without greenhouse gas emissions. Thus far, economic studies of nuclear hydrogen tend to focus on the levelized cost of hydrogen without accounting for the risks and uncertainties that potential investors would face. We present a financial model based on real options theory to assess the profitability of different nuclear hydrogen production technologies in evolving electricity and hydrogen markets. The model uses Monte Carlo simulations to represent uncertainty in future hydrogen and electricity prices. It computes the expected value and the distribution of discounted profits from nuclear hydrogen production plants. Moreover, the model quantifies the value of the option to switch between hydrogen and electricity production, depending on what is more profitable to sell. We use the model to analyze the market viability of four potential nuclear hydrogen technologies and conclude that flexibility in output product is likely to add significant economic value for an investor in nuclear hydrogen. This should be taken into account in the development phase of nuclear hydrogen technologies.

  3. COGNITIVE ECONOMICS.

    PubMed

    Kimball, Miles

    2015-06-01

    Cognitive economics is the economics of what is in people's minds. It is a vibrant area of research (much of it within behavioural economics, labour economics and the economics of education) that brings into play novel types of data, especially novel types of survey data. Such data highlight the importance of heterogeneity across individuals and highlight thorny issues for welfare economics. A key theme of cognitive economics is finite cognition (often misleadingly called "bounded rationality"), which poses theoretical challenges that call for versatile approaches. Cognitive economics brings a rich toolbox to the task of understanding a complex world.

  4. COGNITIVE ECONOMICS

    PubMed Central

    KIMBALL, MILES

    2017-01-01

    Cognitive economics is the economics of what is in people’s minds. It is a vibrant area of research (much of it within behavioural economics, labour economics and the economics of education) that brings into play novel types of data, especially novel types of survey data. Such data highlight the importance of heterogeneity across individuals and highlight thorny issues for welfare economics. A key theme of cognitive economics is finite cognition (often misleadingly called “bounded rationality”), which poses theoretical challenges that call for versatile approaches. Cognitive economics brings a rich toolbox to the task of understanding a complex world. PMID:28149186

  5. Solar energy system economic evaluation: Fern Tunkhannock, Tunkhannock, Pennsylvania

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The economic performance of an Operational Test Site (OTS) is described. The long term economic performance of the system at its installation site and extrapolation to four additional selected locations to demonstrate the viability of the design over a broad range of environmental and economic conditions is reported. Topics discussed are: system description, study approach, economic analysis and system optimization, and technical and economical results of analysis. Data for the economic analysis are generated through evaluation of the OTS. The simulation is based on the technical results of the seasonal report simulation. In addition localized and standard economic parameters are used for economic analysis.

  6. Economic evaluation of the Annual Cycle Energy System. Volume I. Executive summary. Final report. [In Minneapolis, Atlanta, and Philadelphia

    SciTech Connect

    Not Available

    1980-05-01

    The objective of this study is to determine the energy effectiveness and the economic viability of the ACES concept. Three different classes of building are investigated, namely: single-family residence; multi-family residence; and commercial office building. The application of ACES to each of these building types is studied in three different climatic regions: Minneapolis, Atlanta, and Philadelphia. Computer programs - ACESIM for the residences and CACESS for the office building - were used, each comprised of four modules: loads; design; simulation; and economic. For each building type in each geographic location, the economic evaluation of the ACES is based on a comparison of the present worth of the ACES to the present worth of a number of conventional systems. The results of this analysis indicate that the economic viability of the ACES is very sensitive to the assumed value of the property tax, maintenace cost, and fuel-escalation rates, while it is relatively insensitive to the assumed values of other parameters. Fortunately, any conceivable change in the fuel-escalation rates would tend to increase the viability of the ACES concept. An increase in the assumed value of the maintenance cost or property tax would tend to make the ACES concept less viable; a decrease in either would tend to make the ACES concept more viable. The detailed results of this analysis are given in Section 5.4 of Volume II. 2 figures, 21 tables.

  7. Salinity effects on viability, metabolic activity and proliferation of three Perkinsus species

    USGS Publications Warehouse

    La, Peyre M.; Casas, S.; La, Peyre J.

    2006-01-01

    Little is known regarding the range of conditions in which many Perkinsus species may proliferate, making it difficult to predict conditions favorable for their expansion, to identify conditions inducing mortality, or to identify instances of potential cross-infectivity among sympatric host species. In this study, the effects of salinity on viability, metabolic activity and proliferation of P. marinus, P. olseni and P. chesapeaki were determined. Specifically, this research examined the effects of 5 salinities (7, 11, 15, 25, 35???), (1) without acclimation, on the viability and metabolic activity of 2 isolates of each Perkinsus species, and (2) with acclimation, on the viability, metabolic activity, size and number of 1 isolate of each species. P. chesapeaki showed the widest range of salinity tolerance of the 3 species, with high viability and cell proliferation at all salinities tested. Although P. chesapeaki originated from low salinity areas (i.e. <15???), several measures (i.e. cell number and metabolic activity) indicated that higher salinities (15, 25???) were more favorable for its growth. P. olseni, originating from high salinity areas, had better viability and proliferation at the higher salinities (15, 25, 35???). Distinct differences in acute salinity response of the 2 P. olseni isolates at lower salinities (7, 11???), however, suggest the need for a more expansive comparison of isolates to better define the lower salinity tolerance. Lastly, P. marinus was more tolerant of the lower salinities (7 and 11???) than P. olseni, but exhibited reduced viability at 7???, even after acclimation. ?? Inter-Research 2006.

  8. Decreased sexual signalling reveals reduced viability in small populations of the drumming wolf spider Hygrolycosa rubrofasciata.

    PubMed Central

    Ahtiainen, Jari J.; Alatalo, Rauno V.; Mappes, Johanna; Vertainen, Laura

    2004-01-01

    One of the important goals in conservation biology is to determine reliable indicators of population viability. Sexual traits have been suggested to indicate population extinction risk, because they may be related to viability through condition dependence. Moreover, condition-dependent sexual traits may be more sensitive indicators of population viability than early life-history traits, because deleterious fitness effects of inbreeding tend to be expressed mainly at the end of the species' life history. However, empirical evidence of the significance of sexual behaviour for population viability is missing. In this study, we examined two male sexual traits and survival in 39 different-sized and isolated natural populations of the wolf spider, Hygrolycosa rubrofasciata. We also used several traits to estimate female reproductive success in 25 populations of H. rubrofasciata. According to previous studies, H. rubrofasciata males have a costly and condition-dependent acoustic signal, courtship drumming, which is the target of female choice. Males with a high drumming rate have considerably higher viability than males with a low drumming rate, and females that mate with the more actively drumming males gain genetic benefits in terms of increased offspring viability. Our results show that males in small populations had both lower survival and lower drumming rate than males in larger populations. However, we did not find any evidence for a decline in important early life-history traits (offspring number, hatching success or offspring body mass) or female body mass in small populations. Our results have two important messages for conservation biology. First, they show that sexual traits can be used as sensitive indicators of population viability. Second, the indirect benefits of female choice in terms of good genes might partially compensate for the reduction of viability in declining populations. Also, our results support the view that deleterious effects of small

  9. Decreased sexual signalling reveals reduced viability in small populations of the drumming wolf spider Hygrolycosa rubrofasciata.

    PubMed

    Ahtiainen, Jari J; Alatalo, Rauno V; Mappes, Johanna; Vertainen, Laura

    2004-09-07

    One of the important goals in conservation biology is to determine reliable indicators of population viability. Sexual traits have been suggested to indicate population extinction risk, because they may be related to viability through condition dependence. Moreover, condition-dependent sexual traits may be more sensitive indicators of population viability than early life-history traits, because deleterious fitness effects of inbreeding tend to be expressed mainly at the end of the species' life history. However, empirical evidence of the significance of sexual behaviour for population viability is missing. In this study, we examined two male sexual traits and survival in 39 different-sized and isolated natural populations of the wolf spider, Hygrolycosa rubrofasciata. We also used several traits to estimate female reproductive success in 25 populations of H. rubrofasciata. According to previous studies, H. rubrofasciata males have a costly and condition-dependent acoustic signal, courtship drumming, which is the target of female choice. Males with a high drumming rate have considerably higher viability than males with a low drumming rate, and females that mate with the more actively drumming males gain genetic benefits in terms of increased offspring viability. Our results show that males in small populations had both lower survival and lower drumming rate than males in larger populations. However, we did not find any evidence for a decline in important early life-history traits (offspring number, hatching success or offspring body mass) or female body mass in small populations. Our results have two important messages for conservation biology. First, they show that sexual traits can be used as sensitive indicators of population viability. Second, the indirect benefits of female choice in terms of good genes might partially compensate for the reduction of viability in declining populations. Also, our results support the view that deleterious effects of small

  10. Viability of microencapsulated bifidobacteria in set yogurt during refrigerated storage.

    PubMed

    Adhikari, K; Mustapha, A; Grün, I U; Fernando, L

    2000-09-01

    Bifidobacteria are probiotic organisms that improve the microbial balance in the human gut. They can be incorporated as live cultures in fermented dairy foods, including yogurt, for transmission to humans. Because bifidobacteria are sensitive to high acidity, their viability in yogurt is limited. The objective of the present study was to investigate the effect of microencapsulation on the viability of bifidobacteria in yogurt during refrigerated storage for 30 d. Live bifidobacterial cells were encapsulated in kappa-carrageenan. Cell enumeration, determination of titratable acidity and pH, quantitation of lactic and acetic acids, and sensory evaluation (consumer test) were carried out on the yogurt samples. Microbiological results showed a decline of 78 and 70.5% in the population of Bifidobacterium longum B6 and B. longum ATCC 15708, respectively, for the treatments containing nonencapsulated cells. No difference in bifidobacterial population was observed in the encapsulated treatments. The acetic acid content in the yogurt with nonencapsulated bifidobacteria was higher than that in the plain yogurt (control) and encapsulated treatments. The increase in lactic acid content during storage was not different among the various treatments for B. longum B6, but was greater for nonencapsulated than encapsulated B. longum 15708 and the control. Consumers judged the nonencapsulated treatment as the most sour, which was likely due to the higher acetic acid content. Consumers preferred the control and nonencapsulated treatments over the encapsulated treatment. Microencapsulation appears to increase the viability of bifidobacteria in yogurt. This technique can be used to transmit bifidobacteria via fermented products provided that sensory characteristics of the product are improved or maintained.

  11. Lactate as a Novel Quantitative Measure of Viability in Schistosoma mansoni Drug Sensitivity Assays

    PubMed Central

    Howe, Stephanie; Zöphel, Dorina; Subbaraman, Harini; Unger, Clemens; Held, Jana; Engleitner, Thomas; Hoffmann, Wolfgang H.

    2014-01-01

    Whole-organism compound sensitivity assays are a valuable strategy in infectious diseases to identify active molecules. In schistosomiasis drug discovery, larval-stage Schistosoma allows the use of a certain degree of automation in the screening of compounds. Unfortunately, the throughput is limited, as drug activity is determined by manual assessment of Schistosoma viability by microscopy. To develop a simple and quantifiable surrogate marker for viability, we targeted glucose metabolism, which is central to Schistosoma survival. Lactate is the end product of glycolysis in human Schistosoma stages and can be detected in the supernatant. We assessed lactate as a surrogate marker for viability in Schistosoma drug screening assays. We thoroughly investigated parameters of lactate measurement and performed drug sensitivity assays by applying schistosomula and adult worms to establish a proof of concept. Lactate levels clearly reflected the viability of schistosomula and correlated with schistosomulum numbers. Compounds with reported potencies were tested, and activities were determined by lactate assay and by microscopy. We conclude that lactate is a sensitive and simple surrogate marker to be measured to determine Schistosoma viability in compound screening assays. Low numbers of schistosomula and the commercial availability of lactate assay reagents make the assay particularly attractive to throughput approaches. Furthermore, standardization of procedures and quantitative evaluation of compound activities facilitate interassay comparisons of potencies and, thus, concerted drug discovery approaches. PMID:25487803

  12. [Nicotinamide influence on pancreatic cells viability].

    PubMed

    Kuchmerovs'ka, T M; Donchenko, H V; Tykhonenko, T M; Huzyk, M M; Stavniĭchuk, R V; Ianits'ka, L V; Stepanenko, S P; Klymenko, A P

    2012-01-01

    The study was undertaken to investigate the modulating effect of nicotinamide (NAm) in different concentrations and under different glucose concentrations on the viability and oxidative stress induced by streptozotocin (STZ, 5 mmol/l) and hydrogen peroxide (H2O2, 100 micromol/l) on isolated rat pancreatic cells of the Langerhans islets in vitro. Cell viability did not depend on the concentration of glucose in the range of 5-20 mmol/l, and in subsequent studies we used glucose in concentration of 10 mmol/l to protect cells against its hypo- and hyperglycemic action. Cytoprotective effect of NAm in concentrations from 5 to 20 mmol/l on cells survival was the same. It was found that the destructive action of STZ and H2O2 during 24 hours on isolated cells of the pancreas resulted in the significant cell death. It was revealed that NAm in concentration of 5 mmol/l not only had cytoprotective effects against STZ and H2O2 but also partially reduced the level of oxidative stress in the investigated cells induced by these compounds. High concentration of NAm, 35 mmol/l, causes cytotoxic effect on the viability of pancreatic islet cells and increase of oxidative stress induced by STZ and H2O2. Most likely these effects could be associated with direct modulatory action of NAm on important effector mechanisms involved in cell death, including PARP-dependent processes, or/and indirectly, through metabolic and antioxidant effects of the compound.

  13. Kinetic viability assays using DRAQ7 probe.

    PubMed

    Wlodkowic, Donald; Akagi, Jin; Dobrucki, Jurek; Errington, Rachel; Smith, Paul J; Takeda, Kazuo; Darzynkiewicz, Zbigniew

    2013-07-01

    Cell death within cell populations is a stochastic process where cell-to-cell variation in temporal progression through the various stages of cell death arises from asynchrony of subtle fluctuations in the signaling pathways. Most cell death assays rely on detection of the specific marker of cell demise at the end-point of cell culturing. Such an approach cannot account for the asynchrony and the stochastic nature of cell response to the death-inducing signal. There is a need therefore for rapid and high-throughput bioassays capable of continuously tracking viability of individual cells from the time of encountering a stress signal up to final stages of their demise. In this context, a new anthracycline derivative, DRAQ7, is gaining increasing interest as an easy-to-use marker capable of long-term monitoring of cell death in real-time. This novel probe neither penetrates the plasma membrane of living cells nor does it affect the cells' susceptibility to the death-inducing agents. However, when the membrane integrity is compromised, DRAQ7 enters cells undergoing demise and binds readily to nuclear DNA to report cell death. Here, we provide three sets of protocols for viability assays using DRAQ7 probe. The first protocol describes the innovative use of single-color DRAQ7 real-time assay to dynamically track cell viability. The second protocol outlines a simplified end-point DRAQ7 staining approach. The final protocol highlights the real-time and multiparametric apoptosis assay utilizing DRAQ7 dye concurrently with tetramethylrhodamine methyl ester (TMRM), the mitochondrial trans-membrane electrochemical potential (ΔΨm) sensing probe.

  14. Echinococcus metacestode: in search of viability markers

    PubMed Central

    Gottstein, Bruno; Wang, Junhua; Blagosklonov, Oleg; Grenouillet, Frédéric; Millon, Laurence; Vuitton, Dominique A.; Müller, Norbert

    2014-01-01

    Epidemiological studies have demonstrated that most humans infected with Echinococcus spp. exhibit resistance to disease. When infection leads to disease, the parasite is partially controlled by host immunity: in case of immunocompetence, the normal alveolar echinococcosis (AE) or cystic echinococcosis (CE) situation, the metacestode grows slowly, and first clinical signs appear years after infection; in case of impaired immunity (AIDS; other immunodeficiencies), uncontrolled proliferation of the metacestode leads to rapidly progressing disease. Assessing Echinococcus multilocularis viability in vivo following therapeutic interventions in AE patients may be of tremendous benefit when compared with the invasive procedures used to perform biopsies. Current options are F18-fluorodeoxyglucose-positron emission tomography (FDG-PET), which visualizes periparasitic inflammation due to the metabolic activity of the metacestode, and measurement of antibodies against recEm18, a viability-associated protein, that rapidly regresses upon metacestode inactivation. For Echinococcus granulosus, similar prognosis-associated follow-up parameters are still lacking but a few candidates may be listed. Other possible markers include functional and diffusion-weighted Magnetic Resonance Imaging (MRI), and measurement of products from the parasite (circulating antigens or DNA), and from the host (inflammation markers, cytokines, or chemokines). Even though some of them have been promising in pilot studies, none has been properly validated in an appropriate number of patients until now to be recommended for further use in clinical settings. There is therefore still a need to develop reliable tools for improved viability assessment to provide the sufficient information needed to reliably withdraw anti-parasite benzimidazole chemotherapy, and a basis for the development of new alternative therapeutic tools. PMID:25429386

  15. Behavioral economics.

    PubMed

    Camerer, Colin F

    2014-09-22

    Behavioral economics uses evidence from psychology and other social sciences to create a precise and fruitful alternative to traditional economic theories, which are based on optimization. Behavioral economics may interest some biologists, as it shifts the basis for theories of economic choice away from logical calculation and maximization and toward biologically plausible mechanisms.

  16. Quintessence reconstructed: New constraints and tracker viability

    SciTech Connect

    Sahlen, Martin; Liddle, Andrew R.; Parkinson, David

    2007-01-15

    We update and extend our previous work reconstructing the potential of a quintessence field from current observational data. We extend the cosmological data set to include new supernova data, plus information from the cosmic microwave background and from baryon acoustic oscillations. We extend the modeling by considering Pade approximant expansions as well as Taylor series, and by using observations to assess the viability of the tracker hypothesis. We find that parameter constraints have improved by a factor of 2, with a strengthening of the preference of the cosmological constant over evolving quintessence models. Present data show some signs, though inconclusive, of favoring tracker models over nontracker models under our assumptions.

  17. Viability of fungal cultures maintained at -70 degrees C.

    PubMed Central

    Pasarell, L; McGinnis, M R

    1992-01-01

    One thousand four hundred forty-seven clinical and environmental isolates of molds, yeasts, aerobic actinomycetes, and algae belonging to 164 genera (382 taxa) maintained on potato dextrose agar at -70 degrees C for periods ranging from 6 months to 13 years were subcultured and then incubated at 25 degrees C to determine their viabilities. Thirty-three isolates, Alternaria alternata (n = 1), Apophysomyces elegans (n = 1), Bipolaris spicifera (n = 1), Blastomyces dermatitidis (n = 4), Cokeromyces recurvatus (n = 1), Coremiella cubispora (n = 1), Cryptococcus ater (n = 1), Curvularia sp. (n = 1), Exserohilum monoceras (n = 1), Exserohilum pedicillatum (n = 1), Exserohilum rostratum (n = 1), Filobasidium floriforme (n = 1), Madurella mycetomatis (n = 1), Oedocephalum spp. (n = 2), Penicillium marneffei (n = 1), Pseudomicrodochium spp. (n = 4), Saksenaea vasiformis (n = 1), Sporothrix sp. (n = 1), and Mycelia Sterilia (n = 8), did not grow after repeated attempts at subculturing. Neither time in storage nor taxonomic classification was associated with a lack of viability. Storage at low temperature for either short or long periods of time is an excellent method for maintaining most medically important fungi. PMID:1572955

  18. Viability of Heterodera glycines Exposed to Fungal Filtrates

    PubMed Central

    Chen, S. Y.; Dickson, D. W.; Mitchell, D. J.

    2000-01-01

    Filtrates from nematode-parasitic fungi have been reported to be toxic to plant-parasitic nematodes. Our objective was to determine the effects of fungal filtrates on second-stage juveniles and eggs of Heterodera glycines. Eleven fungal species that were isolated from cysts extracted from a soybean field in Florida were tested on J2, and five species were tested on eggs in vitro. Each fungal species was grown in Czapek-Dox broth and malt extract broth. No toxic activity was observed for fungi grown in Czapek-Dox broth. Filtrates from Paecilomyces lilacinus, Stagonospora heteroderae, Neocosmospora vasinfecta, and Fusarium solani grown in malt extract broth were toxic to J2, whereas filtrates from Exophiala pisciphila, Fusarium oxysporum, Gliocladium catenulatum, Pyrenochaeta terrestris, Verticillium chlamydosporium, and sterile fungi 1 and 2 were not toxic to J2. Filtrates of P. lilacinus, S. heteroderae, and N. vasinfecta grown in malt extract broth reduced egg viability, whereas F. oxysporum and P. terrestris filtrates had no effect on egg viability. PMID:19270965

  19. Artificial evolution by viability rather than competition.

    PubMed

    Maesani, Andrea; Fernando, Pradeep Ruben; Floreano, Dario

    2014-01-01

    Evolutionary algorithms are widespread heuristic methods inspired by natural evolution to solve difficult problems for which analytical approaches are not suitable. In many domains experimenters are not only interested in discovering optimal solutions, but also in finding the largest number of different solutions satisfying minimal requirements. However, the formulation of an effective performance measure describing these requirements, also known as fitness function, represents a major challenge. The difficulty of combining and weighting multiple problem objectives and constraints of possibly varying nature and scale into a single fitness function often leads to unsatisfactory solutions. Furthermore, selective reproduction of the fittest solutions, which is inspired by competition-based selection in nature, leads to loss of diversity within the evolving population and premature convergence of the algorithm, hindering the discovery of many different solutions. Here we present an alternative abstraction of artificial evolution, which does not require the formulation of a composite fitness function. Inspired from viability theory in dynamical systems, natural evolution and ethology, the proposed method puts emphasis on the elimination of individuals that do not meet a set of changing criteria, which are defined on the problem objectives and constraints. Experimental results show that the proposed method maintains higher diversity in the evolving population and generates more unique solutions when compared to classical competition-based evolutionary algorithms. Our findings suggest that incorporating viability principles into evolutionary algorithms can significantly improve the applicability and effectiveness of evolutionary methods to numerous complex problems of science and engineering, ranging from protein structure prediction to aircraft wing design.

  20. Population Viability Analysis of Riverine Fishes

    SciTech Connect

    Bates, P.; Chandler, J.; Jager, H.I.; Lepla, K.; Van Winkle, W.

    1999-04-12

    Many utilities face conflkts between two goals: cost-efficient hydropower generation and protecting riverine fishes. Research to develop ecological simulation tools that can evaluate alternative mitigation strategies in terms of their benefits to fish populations is vital to informed decision-making. In this paper, we describe our approach to population viability analysis of riverine fishes in general and Snake River white sturgeon in particular. We are finding that the individual-based modeling approach used in previous in-stream flow applications is well suited to addressing questions about the viability of species of concern for several reasons. Chief among these are: (1) the abiIity to represent the effects of individual variation in life history characteristics on predicted population viabili~, (2) the flexibili~ needed to quanti~ the ecological benefits of alternative flow management options by representing spatial and temporal variation in flow and temperaturty and (3) the flexibility needed to quantifi the ecological benefits of non-flow related manipulations (i.e., passage, screening and hatchery supplementation).

  1. Recent trends in automobile recycling: An energy and economic assessment

    SciTech Connect

    Curlee, T.R.; Das, S.; Rizy, C.G.; Schexanyder, S.M.

    1994-03-01

    Recent and anticipated trends in the material composition of domestic and imported automobiles and the increasing cost of landfilling the non-recyclable portion of automobiles (automobile shredder residue or ASR) pose questions about the future of automobile recycling. This report documents the findings of a study sponsored by the US Department of Energy`s Office of Environmental Analysis to examine the impacts of these and other relevant trends on the life-cycle energy consumption of automobiles and on the economic viability of the domestic automobile recycling industry. More specifically, the study (1) reviewed the status of the automobile recycling industry in the United States, including the current technologies used to process scrapped automobiles and the challenges facing the automobile recycling industry; (2) examined the current status and future trends of automobile recycling in Europe and Japan, with the objectives of identifying ``lessons learned`` and pinpointing differences between those areas and the United States; (3) developed estimates of the energy system impacts of the recycling status quo and projections of the probable energy impacts of alternative technical and institutional approaches to recycling; and (4) identified the key policy questions that will determine the future economic viability of automobile shredder facilities in the United States.

  2. Lake eutrophication and environmental change: A viability framework for resilience, vulnerability and adaptive capacity

    NASA Astrophysics Data System (ADS)

    Mathias, Jean-Denis; Rougé, Charles; Deffuant, Guillaume

    2013-04-01

    We present a simple stochastic model of lake eutrophication to demonstrate how the mathematical framework of viability theory fosters operational definitions of resilience, vulnerability and adaptive capacity, and then helps understand which response one should bring to environmental changes. The model represents the phosphorus dynamics, given that high concentrations trigger a regime change from oligotrophic to eutrophic, and causes ecological but also economic losses, for instance from tourism. Phosphorus comes from agricultural inputs upstream of the lake, and we will consider a stochastic input. We consider the system made of both the lake and its upstream region, and explore how to maintain the desirable ecological and economic properties of this system. In the viability framework, we translate these desirable properties into state constraints, then examine how, given the dynamics of the model and the available policy options, the properties can be kept. The set of states for which there exists a policy to keep the properties is called the viability kernel. We extend this framework to both major perturbations and long-term environmental changes. In our model, since the phosphorus inputs and outputs from the lake depend on rainfall, we will focus on extreme rainfall events and long-term changes in the rainfall regime. They can be described as changes in the state of the system, and may displace it outside the viability kernel. Its response can then be described using the concepts of resilience, vulnerability and adaptive capacity. Resilience is the capacity to recover by getting back to the viability kernel where the dynamics keep the system safe, and in this work we assume it to be the first objective of management. Computed for a given trajectory, vulnerability is a measure of the consequence of violating a property. We propose a family of functions from which cost functions and other vulnerability indicators can be derived for any trajectory. There can be

  3. FAK and HAS Inhibition Synergistically Decrease Colon Cancer Cell Viability and Affect Expression of Critical Genes

    PubMed Central

    Heffler, Melissa; Golubovskaya, Vita; Conroy, Jeffrey; Liu, Song; Wang, Dan; Cance, William; Dunn, Kelli B.

    2013-01-01

    Focal adhesion kinase (FAK), hyaluronan (HA), and hyaluronan synthase-3 (HAS3) have been implicated in cancer growth and progression. FAK inhibition with the small molecule inhibitor Y15 decreases colon cancer cell growth in vitro and in vivo. HAS3 inhibition in colon cancer cells decreases FAK expression and activation, and exogenous HA increases FAK activation. We sought to determine the genes affected by HAS and FAK inhibition and hypothesized that dual inhibition would synergistically inhibit viability. Y15 (FAK inhibitor) and the HAS inhibitor 4-methylumbelliferone (4-MU) decreased viability in a dose dependent manner; viability was further inhibited by treatment with Y15 and 4-MU in colon cancer cells. HAS inhibited cells treated with 2μM of Y15 showed significantly decreased viability compared to HAS scrambled cells treated with the same dose (p<0.05) demonstrating synergistic inhibition of viability with dual FAK/HAS inhibition. Microarray analysis showed more than 2-fold up- or down-regulation of 121 genes by HAS inhibition, and 696 genes by FAK inhibition (p<0.05) and revealed 29 common genes affected by both signaling. Among the genes affected by FAK or HAS3 inhibition were genes, playing role in apoptosis, cell cycle regulation, adhesion, transcription, heat-shock and WNT pathways. Thus, FAK or HAS inhibition decreases SW620 viability and affects several similar genes, which are involved in the regulation of tumor survival. Dual inhibition of FAK and HAS3 decreases viability to a greater degree than with either agent alone, and suggests that synergistic inhibition of colon cancer cell growth can result from affecting similar genetic pathways. PMID:22934709

  4. FAK and HAS inhibition synergistically decrease colon cancer cell viability and affect expression of critical genes.

    PubMed

    Heffler, Melissa; Golubovskaya, Vita M; Conroy, Jeffrey; Liu, Song; Wang, Dan; Cance, William G; Dunn, Kelli B

    2013-05-01

    Focal adhesion kinase (FAK), hyaluronan (HA), and hyaluronan synthase-3 (HAS3) have been implicated in cancer growth and progression. FAK inhibition with the small molecule inhibitor Y15 decreases colon cancer cell growth in vitro and in vivo. HAS3 inhibition in colon cancer cells decreases FAK expression and activation, and exogenous HA increases FAK activation. We sought to determine the genes affected by HAS and FAK inhibition and hypothesized that dual inhibition would synergistically inhibit viability. Y15 (FAK inhibitor) and the HAS inhibitor 4-methylumbelliferone (4-MU) decreased viability in a dose dependent manner; viability was further inhibited by treatment with Y15 and 4-MU in colon cancer cells. HAS inhibited cells treated with 2 μM of Y15 showed significantly decreased viability compared to HAS scrambled cells treated with the same dose (p < 0.05) demonstrating synergistic inhibition of viability with dual FAK/HAS inhibition. Microarray analysis showed more than 2-fold up- or down-regulation of 121 genes by HAS inhibition, and 696 genes by FAK inhibition (p < 0.05) and revealed 29 common genes affected by both signaling. Among the genes affected by FAK or HAS3 inhibition were genes, playing role in apoptosis, cell cycle regulation, adhesion, transcription, heatshock and WNT pathways. Thus, FAK or HAS inhibition decreases SW620 viability and affects several similar genes, which are involved in the regulation of tumor survival. Dual inhibition of FAK and HAS3 decreases viability to a greater degree than with either agent alone, and suggests that synergistic inhibition of colon cancer cell growth can result from affecting similar genetic pathways.

  5. Viability of Selected Microorganisms in Hydrocarbon Fuels.

    PubMed

    Hedrick, H G; Carroll, M T; Owen, H P; Pritchard, D J

    1963-11-01

    A laboratory study of the viability of selected microorganisms in a hydrocarbon fuel medium was carried out on 19 species of microorganisms, representative of the types found as natural contaminants in aircraft fuels. More species remained viable when inoculated in pure cultures than when inoculated in mixed (composite) cultures. Of the 19 species selected, 10 were still viable after 3 months and 5 were viable after 4 months in the pure culture inoculants. In the complete composite culture inoculant, the bacterial species which were viable at the end of 4 months were the same as those found in the pure culture inoculant. No fungi remained viable in the complete composite cultures after a 3-week period. The microorganisms which remain viable in a hydrocarbon fuel medium are considered indicative of a satisfactory inoculum to be used as a test culture in laboratory analysis of mechanical control techniques.

  6. VIABILITY OF COLIFORM BACTERIA IN ANTARCTIC SOIL.

    PubMed

    BOYD, W L; BOYD, J W

    1963-05-01

    Boyd, William L. (Ohio State University, Columbus) and Josephine W. Boyd. Viability of coliform bacteria in antarctic soil. J. Bacteriol. 85:1121-1123. 1963.-The distribution of coliform bacteria in soils of Ross Island and the nearby mainland was studied. None was found in almost all of the samples collected, including some from the Adelie penguin rookeries at Cape Royds and Cape Crozier and in soil at the McMurdo Base which had been recently contaminated by human sewage. Samples of pony manure left from previous expeditions were also negative, with one exception where Escherichia coli were present. Studies carried out with two freshly isolated human strains of E. coli and the isolate from pony manure showed that the death rate was extremely rapid, although the animal strain was much more resistant to the various factors of the environment causing death.

  7. Incorporating evolutionary processes into population viability models.

    PubMed

    Pierson, Jennifer C; Beissinger, Steven R; Bragg, Jason G; Coates, David J; Oostermeijer, J Gerard B; Sunnucks, Paul; Schumaker, Nathan H; Trotter, Meredith V; Young, Andrew G

    2015-06-01

    We examined how ecological and evolutionary (eco-evo) processes in population dynamics could be better integrated into population viability analysis (PVA). Complementary advances in computation and population genomics can be combined into an eco-evo PVA to offer powerful new approaches to understand the influence of evolutionary processes on population persistence. We developed the mechanistic basis of an eco-evo PVA using individual-based models with individual-level genotype tracking and dynamic genotype-phenotype mapping to model emergent population-level effects, such as local adaptation and genetic rescue. We then outline how genomics can allow or improve parameter estimation for PVA models by providing genotypic information at large numbers of loci for neutral and functional genome regions. As climate change and other threatening processes increase in rate and scale, eco-evo PVAs will become essential research tools to evaluate the effects of adaptive potential, evolutionary rescue, and locally adapted traits on persistence.

  8. Artificial Evolution by Viability Rather than Competition

    PubMed Central

    Maesani, Andrea; Fernando, Pradeep Ruben; Floreano, Dario

    2014-01-01

    Evolutionary algorithms are widespread heuristic methods inspired by natural evolution to solve difficult problems for which analytical approaches are not suitable. In many domains experimenters are not only interested in discovering optimal solutions, but also in finding the largest number of different solutions satisfying minimal requirements. However, the formulation of an effective performance measure describing these requirements, also known as fitness function, represents a major challenge. The difficulty of combining and weighting multiple problem objectives and constraints of possibly varying nature and scale into a single fitness function often leads to unsatisfactory solutions. Furthermore, selective reproduction of the fittest solutions, which is inspired by competition-based selection in nature, leads to loss of diversity within the evolving population and premature convergence of the algorithm, hindering the discovery of many different solutions. Here we present an alternative abstraction of artificial evolution, which does not require the formulation of a composite fitness function. Inspired from viability theory in dynamical systems, natural evolution and ethology, the proposed method puts emphasis on the elimination of individuals that do not meet a set of changing criteria, which are defined on the problem objectives and constraints. Experimental results show that the proposed method maintains higher diversity in the evolving population and generates more unique solutions when compared to classical competition-based evolutionary algorithms. Our findings suggest that incorporating viability principles into evolutionary algorithms can significantly improve the applicability and effectiveness of evolutionary methods to numerous complex problems of science and engineering, ranging from protein structure prediction to aircraft wing design. PMID:24489790

  9. Glufosinate does not affect floral morphology and pollen viability in glufosinate-resistant cotton (Gossypium hirsutum)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies were conducted to determine whether glufosinate treatments to glufosinate-resistant cotton caused changes in floral morphology, pollen viability, and seed set. Four glufosinate treatments were included: (1) glufosinate applied postemergence over the top (POST) at the four-leaf stage, (2) glu...

  10. Thermoforming of Tracheal Cartilage: Viability, Shape Change, and Mechanical Behavior

    PubMed Central

    Chae, Yongseok; Protsenko, Dmitriy; Holden, Paul K.; Chlebicki, Cara; Wong, Brian J.F.

    2014-01-01

    Background and Objectives Trauma, emergent tracheostomy, and prolonged intubation are common causes of severe deformation and narrowing of the trachea. Laser technology may be used to reshape tracheal cartilage using minimally invasive methods. The objectives of this study were to determine: (1) the dependence of tracheal cartilage shape change on temperature and laser dosimetry using heated saline bath immersion and laser irradiation, respectively, (2) the effect of temperature on the mechanical behavior of cartilage, and (3) tissue viability as a function of laser dosimetry. Materials and Methods Ex vivo rabbit trachea cartilage specimens were bent and secured around a cylinder (6 mm), and then immersed in a saline bath (45 and 72°C) for 5– 100 seconds. In separate experiments, tracheal specimens were irradiated with a diode laser (λ = 1.45 μm, 220–400 J/cm2). Mechanical analysis was then used to determine the elastic modulus in tension after irradiation. Fluorescent viability assays combined with laser scanning confocal microscopy (LSCM) were employed to image and identify thermal injury regions. Results Shape change transition zones, between 62 and 66°C in the saline heating bath and above power densities of 350 J/cm2 (peak temperatures 65±10°C) for laser irradiation were identified. Above these zones, the elastic moduli were higher (8.2±4 MPa) than at lower temperatures (4.5±3 MPa). LSCM identified significant loss of viable chondrocytes within the laser-irradiation zones. Conclusion Our results indicate a change in mechanical properties occurs with laser irradiation and further demonstrates that significant thermal damage is concurrent with clinically relevant shape change in the elastic cartilage tissues of the rabbit trachea using the present laser and dosimetry parameters. PMID:18798288

  11. Economics of residue harvest: Regional partnership evaluation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Economic analyses on the viability of corn (Zea mays, L.) stover harvest for bioenergy production have largely been based on simulation modeling. While some studies have utilized field research data, most field-based analyses have included a limited number of sites and a narrow geographic distributi...

  12. Dry heat effects on survival of indigenous soil particle microflora and particle viability studies of Kennedy Space Center soil

    NASA Technical Reports Server (NTRS)

    Ruschmeyer, O. R.; Pflug, I. J.; Gove, R.; Heisserer, Y.

    1975-01-01

    Research efforts were concentrated on attempts to obtain data concerning the dry heat resistance of particle microflora in Kennedy Space Center soil samples. The in situ dry heat resistance profiles at selected temperatures for the aggregate microflora on soil particles of certain size ranges were determined. Viability profiles of older soil samples were compared with more recently stored soil samples. The effect of increased particle numbers on viability profiles after dry heat treatment was investigated. These soil particle viability data for various temperatures and times provide information on the soil microflora response to heat treatment and are useful in making selections for spacecraft sterilization cycles.

  13. Use of flow cytometry to assess chondrocyte viability after laser reshaping of cartilage

    NASA Astrophysics Data System (ADS)

    Rasouli, Alexandre; Kim, Charlton C.; Basu, Reshmi; Wong, Brian J.

    2000-05-01

    Lasers have been shown to cause permanent shape change in cartilage via photothermally induced mechanical stress relaxation. While the biophysical properties of cartilage during laser irradiation have been studied, tissue viability following laser irradiation has not been fully characterized. In this study, cell viability staining and flow cytometry were used to determine chondrocyte viability following photothermal stress relaxation. Porcine septal cartilage slabs (10 X 25 X 1.5 mm) were irradiated with light from a Nd:YAG laser ((lambda) equals 1.32 micrometer, 25 W/cm2) while surface temperature, stress relaxation, and diffuse reflectance were recorded. Each slab received one, two, or three laser exposures (respective exposure times of 6.7, 7.2, 10 s), determined from measurements of diffuse reflectance, which correlate with mechanical stress relaxation. Irradiated samples were then divided into two groups analyzed immediately and at five days following laser exposure (the latter group was maintained in culture). Chondrocytes were isolated following serial enzymatic digestion with hyaluronidase, protease, and collagenase II for a total of 17 hours. Chondrocytes were then stained using SYTOR/DEAD RedTM (Molecular Probes; Eugene, OR) wherein live cells stained green (530 nm) and dead cells stained red (630 nm) when excited at 488 nm. A flow cytometer (FACScan, Becton Dickinson, Franklin Lakes, NJ) was then used to detect differential cell fluorescence; size; granularity; and the number of live cells, dead cells, and post irradiation debris in each treatment population. Nearly 60% of chondrocytes from reshaped cartilage samples isolated shortly after irradiation, were viable as determined using flow cytometry while non- irradiated controls were 100 percent viable. Specimens irradiated two or three times with the laser demonstrated increasing amounts of cellular debris along with a reduction in chondrocyte viability: 31 percent following two laser exposures, and 16

  14. Stimulating Economics

    ERIC Educational Resources Information Center

    Banaian, King

    2009-01-01

    With the current economic slump possibly the deepest since the Great Depression, interest in the subject of macroeconomics has reignited, and the number of students majoring in economics has increased during the last two years. While this would appear to be good news for educators in the economics field, the profession is nervous about more than…

  15. Fault Detection and Isolation using Viability Theory and Interval Observers

    NASA Astrophysics Data System (ADS)

    Ghaniee Zarch, Majid; Puig, Vicenç; Poshtan, Javad

    2017-01-01

    This paper proposes the use of interval observers and viability theory in fault detection and isolation (FDI). Viability theory develops mathematical and algorithmic methods for investigating the adaptation to viability constraints of evolutions governed by complex systems under uncertainty. These methods can be used for checking the consistency between observed and predicted behavior by using simple sets that approximate the exact set of possible behavior (in the parameter or state space). In this paper, fault detection is based on checking for an inconsistency between the measured and predicted behaviors using viability theory concepts and sets. Finally, an example is provided in order to show the usefulness of the proposed approach.

  16. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of CO2 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales, Class III

    SciTech Connect

    Perri, Pasquale R.; Cooney, John; Fong, Bill; Julander, Dale; Marasigan, Aleks; Morea, Mike; Piceno, Deborah; Stone, Bill; Emanuele, Mark; Sheffield, Jon; Wells, Jeff; Westbrook, Bill; Karnes, Karl; Pearson, Matt; Heisler, Stuart

    2000-04-24

    The primary objective of this project was to conduct advanced reservoir characterization and modeling studies in the Antelope Shale of the Bureau Vista Hills Field. Work was subdivided into two phases or budget periods. The first phase of the project focused on a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work would then be used to evaluate how the reservoir would respond to enhanced oil recovery (EOR) processes such as of CO2 flooding. The second phase of the project would be to implement and evaluate a CO2 in the Buena Vista Hills Field. A successful project would demonstrate the economic viability and widespread applicability of CO2 flooding in siliceous shale reservoirs of the San Joaquin Valley.

  17. Novel Sensor-Enabled Ex Vivo Bioreactor: A New Approach towards Physiological Parameters and Porcine Artery Viability

    PubMed Central

    Mundargi, Raghavendra; Venkataraman, Divya; Kumar, Saranya; Mogal, Vishal; Ortiz, Raphael; Loo, Joachim; Venkatraman, Subbu; Steele, Terry

    2015-01-01

    The aim of the present work is to design and construct an ex vivo bioreactor system to assess the real time viability of vascular tissue. Porcine carotid artery as a model tissue was used in the ex vivo bioreactor setup to monitor its viability under physiological conditions such as oxygen, pressure, temperature, and flow. The real time tissue viability was evaluated by monitoring tissue metabolism through a fluorescent indicator “resorufin.” Our ex vivo bioreactor allows real time monitoring of tissue responses along with physiological conditions. These ex vivo parameters were vital in determining the tissue viability in sensor-enabled bioreactor and our initial investigations suggest that, porcine tissue viability is considerably affected by high shear forces and low oxygen levels. Histological evaluations with hematoxylin and eosin and Masson's trichrome staining show intact endothelium with fresh porcine tissue whereas tissues after incubation in ex vivo bioreactor studies indicate denuded endothelium supporting the viability results from real time measurements. Hence, this novel viability sensor-enabled ex vivo bioreactor acts as model to mimic in vivo system and record vascular responses to biopharmaceutical molecules and biomedical devices. PMID:26609536

  18. High speed measurement of corn seed viability using hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Ambrose, Ashabahebwa; Kandpal, Lalit Mohan; Kim, Moon S.; Lee, Wang-Hee; Cho, Byoung-Kwan

    2016-03-01

    Corn is one of the most cultivated crops all over world as food for humans as well as animals. Optimized agronomic practices and improved technological interventions during planting, harvesting and post-harvest handling are critical to improving the quantity and quality of corn production. Seed germination and vigor are the primary determinants of high yield notwithstanding any other factors that may play during the growth period. Seed viability may be lost during storage due to unfavorable conditions e.g. moisture content and temperatures, or physical damage during mechanical processing e.g. shelling, or over heating during drying. It is therefore vital for seed companies and farmers to test and ascertain seed viability to avoid losses of any kind. This study aimed at investigating the possibility of using hyperspectral imaging (HSI) technique to discriminate viable and nonviable corn seeds. A group of corn samples were heat treated by using microwave process while a group of seeds were kept as control group (untreated). The hyperspectral images of corn seeds of both groups were captured between 400 and 2500 nm wave range. Partial least squares discriminant analysis (PLS-DA) was built for the classification of aged (heat treated) and normal (untreated) corn seeds. The model showed highest classification accuracy of 97.6% (calibration) and 95.6% (prediction) in the SWIR region of the HSI. Furthermore, the PLS-DA and binary images were capable to provide the visual information of treated and untreated corn seeds. The overall results suggest that HSI technique is accurate for classification of viable and non-viable seeds with non-destructive manner.

  19. The viability of photovoltaics on the Martian surface

    NASA Technical Reports Server (NTRS)

    Gaier, James R.; Perez-Davis, Marla E.

    1994-01-01

    The viability of photovoltaics (PV) on the Martian surface may be determined by their ability to withstand significant degradation in the Martian environment. Probably the greatest threat is posed by fine dust particles which are continually blown about the surface of the planet. In an effort to determine the extent of the threat, and to investigate some abatement strategies, a series of experiments were conducted in the Martian Surface Wind Tunnel (MARSWIT) at NASA Ames Research Center. The effects of dust composition, particle size, wind velocity, angle of attack, and protective coatings on the transmittance of light through PV coverglass were determined. Both initially clear and initially dusted samples were subjected both to clear winds and simulated dust storms in the MARSWIT. It was found that wind velocity, particle size, and angle of attack are important parameters affecting occlusion of PV surfaces, while dust composition and protective coatings were not. Neither induced turbulence nor direct current biasing up to 200 volts were effective abatement techniques. Abrasion diffused the light impinging on the PV cells, but did not reduce total coverglass transmittance by more than a few percent.

  20. Behavioral Economics

    PubMed Central

    Reed, Derek D.; Niileksela, Christopher R.; Kaplan, Brent A.

    2013-01-01

    In recent years, behavioral economics has gained much attention in psychology and public policy. Despite increased interest and continued basic experimental studies, the application of behavioral economics to therapeutic settings remains relatively sparse. Using examples from both basic and applied studies, we provide an overview of the principles comprising behavioral economic perspectives and discuss implications for behavior analysts in practice. A call for further translational research is provided. PMID:25729506

  1. Evidence for substantial maintenance of membrane integrity and cell viability in normally developing grape (Vitis vinifera L.) berries throughout development.

    PubMed

    Krasnow, Mark; Matthews, Mark; Shackel, Ken

    2008-01-01

    Fluorescein diacetate (FDA) was used as a vital stain to assay membrane integrity (cell viability) in mesocarp tissue of the developing grape (Vitis vinifera L.) berry in order to test the hypothesis that there is a substantial loss of compartmentation in these cells during ripening. This technique was also used to determine whether loss of viability was associated with symptoms of a ripening disorder known as berry shrivel. FDA fluorescence of berry cells was rapid, bright, and stable for over 1 h at room temperature. Confocal microscopy detected FDA staining through two to three intact surface cell layers (300-400 mum) of bisected berries, and showed that the fluorescence was confined to the cytoplasm, indicating the maintenance of integrity in both cytoplasmic as well as vacuolar membranes, and the presence of active cytoplasmic esterases. FDA clearly discriminated between living cells and freeze-killed cells, and exhibited little, if any, non-specific staining. Propidium iodide and DAPI, both widely used to assess cell viability, were unable to discriminate between living and freeze-killed cells, and did not specifically stain the nuclei of dead cells. For normally developing berries under field conditions there was no evidence of viability loss until about 40 d after veraison, and the majority (80%) of mesocarp cells remained viable past commercial harvest (26 degrees Brix). These results are inconsistent with current models of grape berry development which hypothesize that veraison is associated with a general loss of compartmentation in mesocarp cells. The observed viability loss was primarily in the locule area around the seeds, suggesting that a localized loss of viability and compartmentation may occur as part of normal fruit development. The cell viability of berry shrivel-affected berries was similar to that of normally developing berries until the onset of visible symptoms (i.e. shrivelling), at which time viability declined in visibly shrivelled

  2. The Use of Water Vapor as a Refrigerant: Impact of Cycle Modifications on Commercial Viability

    SciTech Connect

    Brandon F. Lachner, Jr.; Gregory F. Nellis; Douglas T. Reindl

    2004-08-30

    This project investigated the economic viability of using water as the refrigerant in a 1000-ton chiller application. The most attractive water cycle configuration was found to be a flash-intercooled, two-stage cycle using centrifugal compressors and direct contact heat exchangers. Component level models were developed that could be used to predict the size and performance of the compressors and heat exchangers in this cycle as well as in a baseline, R-134a refrigeration cycle consistent with chillers in use today. A survey of several chiller manufacturers provided information that was used to validate and refine these component models. The component models were integrated into cycle models that were subsequently used to investigate the life-cycle costs of both an R-134a and water refrigeration cycle. It was found that the first cost associated with the water as a refrigerant cycle greatly exceeded the savings in operating costs associated with its somewhat higher COP. Therefore, the water refrigeration cycle is not an economically attractive option to today's R-134a refrigeration system. There are a number of other issues, most notably the requirements associated with purging non-condensable gases that accumulate in a direct contact heat exchanger, which will further reduce the economic viability of the water cycle.

  3. Assessment of cryopreserved donor skin viability: the experience of the regional tissue bank of Siena.

    PubMed

    Pianigiani, E; Tognetti, L; Ierardi, F; Mariotti, G; Rubegni, P; Cevenini, G; Perotti, R; Fimiani, M

    2016-06-01

    Skin allografts from cadaver donors are an important resource for treating extensive burns, slow-healing wounds and chronic ulcers. A high level of cell viability of cryopreserved allografts is often required, especially in burn surgery, in Italy. Thus, we aimed to determine which conditions enable procurement of highly viable skin in our Regional Skin Bank of Siena. For this purpose, we assessed cell viability of cryopreserved skin allografts procured between 2011 and 2013 from 127 consecutive skin donors, before and after freezing (at day 15, 180, and 365). For each skin donor, we collected data concerning clinical history (age, sex, smoking, phototype, dyslipidemia, diabetes, cause of death), donation process (multi-tissue or multi-organ) and timing of skin procurement (assessment of intervals such as death-harvesting, harvesting-banking, death-banking). All these variables were analysed in the whole case study (127 donors) and in different groups (e.g. multi-organ donors, non refrigerated multi-tissue donors, refrigerated multi-tissue donors) for correlations with cell viability. Our results indicated that cryopreserved skin allografts with higher cell viability were obtained from female, non smoker, heartbeating donors died of cerebral haemorrhage, and were harvested within 2 h of aortic clamping and banked within 12 h of harvesting (13-14 h from clamping). Age, cause of death and dyslipidaemia or diabetes did not appear to influence cell viability. To maintain acceptable cell viability, our skin bank needs to reduce the time interval between harvesting and banking, especially for refrigerated donors.

  4. Quantifying spore viability of the honey bee pathogen Nosema apis using flow cytometry.

    PubMed

    Peng, Yan; Lee-Pullen, Tracey F; Heel, Kathy; Millar, A Harvey; Baer, Boris

    2014-05-01

    Honey bees are hosts to more than 80 different parasites, some of them being highly virulent and responsible for substantial losses in managed honey bee populations. The study of honey bee pathogens and their interactions with the bees' immune system has therefore become a research area of major interest. Here we developed a fast, accurate and reliable method to quantify the viability of spores of the honey bee gut parasite Nosema apis. To verify this method, a dilution series with 0, 25, 50, 75, and 100% live N. apis was made and SYTO 16 and Propidium Iodide (n = 35) were used to distinguish dead from live spores. The viability of spores in each sample was determined by flow cytometry and compared with the current method based on fluorescence microscopy. Results show that N. apis viability counts using flow cytometry produced very similar results when compared with fluorescence microscopy. However, we found that fluorescence microscopy underestimates N. apis viability in samples with higher percentages of viable spores, the latter typically being what is found in biological samples. A series of experiments were conducted to confirm that flow cytometry allows the use of additional fluorescent dyes such as SYBR 14 and SYTOX Red (used in combination with SYTO 16 or Propidium Iodide) to distinguish dead from live spores. We also show that spore viability quantification with flow cytometry can be undertaken using substantially lower dye concentrations than fluorescence microscopy. In conclusion, our data show flow cytometry to be a fast, reliable method to quantify N. apis spore viabilities, which has a number of advantages compared with existing methods.

  5. In vitro pollen viability and pollen germination in cherry laurel (Prunus laurocerasus L.).

    PubMed

    Sulusoglu, Melekber; Cavusoglu, Aysun

    2014-01-01

    Pollen quality is important for growers and breeders. This study was carried out to determine in vitro pollen viability and pollen germination in seven genotypes of cherry laurel (Prunus laurocerasus L.). Two pollen viability tests, TTC (2,3,5-triphenyl tetrazolium chloride) and IKI (iodine potassium iodide), were used. Pollen traits of genotypes were studied using an in vitro medium containing 0%, 5%, 10%, 15%, and 20% sucrose to determine the best sucrose concentrations for germination. In the second step, the germinated pollen was counted 1, 4, 6, 10, 12, 24, and 48 hours later until there was no further germination. The viability rates were different according to genotypes and tests used. The IKI and TTC staining tests and pollen germination had low correlation (r(2) = 0.0614 and r(2) = 0.0015, resp.). Painted pollen rate was higher and pollen was well-stained with IKI test and pollen viability estimated with TTC staining test was better than that estimated with the IKI staining test. 15% sucrose gave the best germination rates in most of the genotypes. Pollen germination rates were recorded periodically from one hour to 48 hours in 15% sucrose and the results showed that pollen germination rates increased after 6 hours of being placed in culture media.

  6. Protection of L. rhamnosus by spray-drying using two prebiotics colloids to enhance the viability.

    PubMed

    Avila-Reyes, Sandra V; Garcia-Suarez, Francisco J; Jiménez, María Teresa; San Martín-Gonzalez, María F; Bello-Perez, Luis A

    2014-02-15

    Protection of probiotics by substances considered as prebiotics can be an alternative to increase their viability in the large intestine. The objective of this study was to use two wall materials (native rice starch and inulin) without bonding agent to protect Lactobacillus rhamnosus during spray-drying and determine the viability of the microorganism under two storage conditions. For spray-drying conditions tested in this work the product yield with native rice starch (NRS) ranged between 65% and 74% whereas for inulin (IN) it ranged between 43% and 54%. In general, IN solutions exhibited higher outlet temperature than NRS dispersions. Capsules of IN had smaller particle size than those of NRS. Due to the higher hydrophilic nature of IN capsules as compared to NRS, IN capsules exhibited higher water activity than NRS capsules. Confocal microscopy showed marked differences between both wall materials, which could in turn cause differences in the release profile of encapsulated microorganisms. Agglomerates of NRS provided better protection to the microorganisms as evidenced by the lower reduction in viability when compared to IN, and this effect was corroborated by the stability study. It is possible to protect probiotics using both colloids, but differences in the viability and stability during storage were determined. The use of IN could prove beneficial in the encapsulation of probiotic strains since this carbohydrate is not hydrolyzed by human digestive enzymes and may act as prebiotic.

  7. In Vitro Pollen Viability and Pollen Germination in Cherry Laurel (Prunus laurocerasus L.)

    PubMed Central

    Sulusoglu, Melekber; Cavusoglu, Aysun

    2014-01-01

    Pollen quality is important for growers and breeders. This study was carried out to determine in vitro pollen viability and pollen germination in seven genotypes of cherry laurel (Prunus laurocerasus L.). Two pollen viability tests, TTC (2,3,5-triphenyl tetrazolium chloride) and IKI (iodine potassium iodide), were used. Pollen traits of genotypes were studied using an in vitro medium containing 0%, 5%, 10%, 15%, and 20% sucrose to determine the best sucrose concentrations for germination. In the second step, the germinated pollen was counted 1, 4, 6, 10, 12, 24, and 48 hours later until there was no further germination. The viability rates were different according to genotypes and tests used. The IKI and TTC staining tests and pollen germination had low correlation (r2 = 0.0614 and r2 = 0.0015, resp.). Painted pollen rate was higher and pollen was well-stained with IKI test and pollen viability estimated with TTC staining test was better than that estimated with the IKI staining test. 15% sucrose gave the best germination rates in most of the genotypes. Pollen germination rates were recorded periodically from one hour to 48 hours in 15% sucrose and the results showed that pollen germination rates increased after 6 hours of being placed in culture media. PMID:25405230

  8. The Location of Viability Genes within a Testcross Framework.

    PubMed

    Chapco, W

    1972-02-01

    The maximum likelihood method is applied to the problem of estimating the positions and effects of viability genes. Whenever testcross linkage data indicate the presence of differential viability, it is hypothesized that there exists one viability gene between each marker. Estimation is possible only for two-point data since the number of independent expectation expressions is less than the number of parameters for three or more markers. It is pointed out that within the two-point testcross system, it is impossible to distinguish between pleiotropic effects of the marker genes and the effect of a middle viability gene, if existent. The methods outlined will be useful in their application to experiments specifically designed to locate induced viability genes.

  9. Viability and functional integrity of washed platelets

    SciTech Connect

    Pineda, A.A.; Zylstra, V.W.; Clare, D.E.; Dewanjee, M.K.; Forstrom, L.A.

    1989-07-01

    The viability and functional integrity of saline- and ACD-saline-washed platelets were compared with those of unwashed platelets. After template bleeding time (TBT) was measured, 15 healthy volunteers underwent plateletpheresis and ingested 600 mg of aspirin. Autologous /sup 111/In-labeled platelets were transfused: unwashed (n = 5), washed with 0.9 percent saline solution (SS) (n = 5), and washed with a buffered 12.6 percent solution of ACD-A in 0.9 percent saline solution (n = 5). After transfusion, we measured TBT at 1, 4, and 24 hours; platelet survival at 10 minutes and 1, 4, and 24 hours and daily for 6 days; and the percentage of uptake in liver and spleen by quantitative whole-body radionuclide scintigraphy at 24 and 190 hours. We found that saline washing affected platelet recovery, 23.47 +/- 12 percent (p less than 0.001) as compared to 52.43 +/- 17 percent (p less than 0.002) for ACD-saline and 73.17 +/- 8 percent for control; that saline washing resulted in a greater liver uptake than control and ACD-saline-washed platelets (31.9 +/- 8% (p less than 0.001) vs 17.7 +/- 4.1 and 19.3 +/- 2.1% (p greater than 0.1), respectively); that, unlike control and ACD-saline-washed platelets, saline-washed platelets did not shorten bleeding time; and that neither type of washing affected survival. Although ACD-saline washing affects recovery, it also results in intact function, normal survival, higher recovery than SS platelets, and no significant liver uptake.

  10. Assessment of tissue viability by polarization spectroscopy

    NASA Astrophysics Data System (ADS)

    Nilsson, G.; Anderson, C.; Henricson, J.; Leahy, M.; O'Doherty, J.; Sjöberg, F.

    2008-09-01

    A new and versatile method for tissue viability imaging based on polarization spectroscopy of blood in superficial tissue structures such as the skin is presented in this paper. Linearly polarized light in the visible wavelength region is partly reflected directly by the skin surface and partly diffusely backscattered from the dermal tissue matrix. Most of the directly reflected light preserves its polarization state while the light returning from the deeper tissue layers is depolarized. By the use of a polarization filter positioned in front of a sensitive CCD-array, the light directly reflected from the tissue surface is blocked, while the depolarized light returning from the deeper tissue layers reaches the detector array. By separating the colour planes of the detected image, spectroscopic information about the amount of red blood cells (RBCs) in the microvascular network of the tissue under investigation can be derived. A theory that utilizes the differences in light absorption of RBCs and bloodless tissue in the red and green wavelength region forms the basis of an algorithm for displaying a colour coded map of the RBC distribution in a tissue. Using a fluid model, a linear relationship (cc. = 0.99) between RBC concentration and the output signal was demonstrated within the physiological range 0-4%. In-vivo evaluation using transepidermal application of acetylcholine by the way of iontophoresis displayed the heterogeneity pattern of the vasodilatation produced by the vasoactive agent. Applications of this novel technology are likely to be found in drug and skin care product development as well as in the assessment of skin irritation and tissue repair processes and even ultimately in a clinic case situation.

  11. Economics Pupils

    ERIC Educational Resources Information Center

    Scott, Alexander; Straker-Cook, Dawn

    1976-01-01

    This paper contains survey information relating to the relative performance of economics pupils at"A" level, their feelings about the subject, and the type of teaching to which they are exposed. The primary concern is to stimulate debate about the issues raised. Journal is available from: Economics Association, Room 340, Hamilton House, Mabledon…

  12. Pollen viability and transgene expression following storage in honey.

    PubMed

    Eady, C; Twell, D; Lindsey, K

    1995-07-01

    Transgenic plants of tobacco and Arabidopsis that produce genetically marked pollen, expressing the reporter gene uidA (gusA), were generated to determine whether pollen proteins can be expressed and stable in honey, a potential route by which foreign proteins might enter the wider environment. Hydrated tobacco pollen was found to lose viability rapidly in honey, while pollen in the natural dehydrated form remained viable for at least several days and in some cases several weeks, as determined by FDA staining activity and germinability. Dehydrated pollen was found to be capable of transient foreign gene expression, following microprojectile bombardment, after incubation in honey for at least 120 h. PCR amplification of transgene sequences in pollen of transgenic plants revealed that pollen DNA can remain relatively intact after 7 weeks in honey. GUS enzyme activity analysis and SDS-PAGE of pollen proteins revealed that foreign and native pollen proteins are stable in pollen incubated in honey for at least 6 weeks. We conclude that pollen may represent an ecologically important vector for transgenic protein products.

  13. Colony Failure Linked to Low Sperm Viability in Honey Bee (Apis mellifera) Queens and an Exploration of Potential Causative Factors.

    PubMed

    Pettis, Jeffery S; Rice, Nathan; Joselow, Katie; vanEngelsdorp, Dennis; Chaimanee, Veeranan

    2016-01-01

    Queen health is closely linked to colony performance in honey bees as a single queen is normally responsible for all egg laying and brood production within the colony. In the U. S. in recent years, queens have been failing at a high rate; with 50% or greater of queens replaced in colonies within 6 months when historically a queen might live one to two years. This high rate of queen failure coincides with the high mortality rates of colonies in the US, some years with >50% of colonies dying. In the current study, surveys of sperm viability in US queens were made to determine if sperm viability plays a role in queen or colony failure. Wide variation was observed in sperm viability from four sets of queens removed from colonies that beekeepers rated as in good health (n = 12; average viability = 92%), were replacing as part of normal management (n = 28; 57%), or where rated as failing (n = 18 and 19; 54% and 55%). Two additional paired set of queens showed a statistically significant difference in viability between colonies rated by the beekeeper as failing or in good health from the same apiaries. Queens removed from colonies rated in good health averaged high viability (ca. 85%) while those rated as failing or in poor health had significantly lower viability (ca. 50%). Thus low sperm viability was indicative of, or linked to, colony performance. To explore the source of low sperm viability, six commercial queen breeders were surveyed and wide variation in viability (range 60-90%) was documented between breeders. This variability could originate from the drones the queens mate with or temperature extremes that queens are exposed to during shipment. The role of shipping temperature as a possible explanation for low sperm viability was explored. We documented that during shipment queens are exposed to temperature spikes (<8 and > 40°C) and these spikes can kill 50% or more of the sperm stored in queen spermathecae in live queens. Clearly low sperm viability is linked

  14. Colony Failure Linked to Low Sperm Viability in Honey Bee (Apis mellifera) Queens and an Exploration of Potential Causative Factors

    PubMed Central

    Pettis, Jeffery S.; Rice, Nathan; Joselow, Katie; vanEngelsdorp, Dennis; Chaimanee, Veeranan

    2016-01-01

    Queen health is closely linked to colony performance in honey bees as a single queen is normally responsible for all egg laying and brood production within the colony. In the U. S. in recent years, queens have been failing at a high rate; with 50% or greater of queens replaced in colonies within 6 months when historically a queen might live one to two years. This high rate of queen failure coincides with the high mortality rates of colonies in the US, some years with >50% of colonies dying. In the current study, surveys of sperm viability in US queens were made to determine if sperm viability plays a role in queen or colony failure. Wide variation was observed in sperm viability from four sets of queens removed from colonies that beekeepers rated as in good health (n = 12; average viability = 92%), were replacing as part of normal management (n = 28; 57%), or where rated as failing (n = 18 and 19; 54% and 55%). Two additional paired set of queens showed a statistically significant difference in viability between colonies rated by the beekeeper as failing or in good health from the same apiaries. Queens removed from colonies rated in good health averaged high viability (ca. 85%) while those rated as failing or in poor health had significantly lower viability (ca. 50%). Thus low sperm viability was indicative of, or linked to, colony performance. To explore the source of low sperm viability, six commercial queen breeders were surveyed and wide variation in viability (range 60–90%) was documented between breeders. This variability could originate from the drones the queens mate with or temperature extremes that queens are exposed to during shipment. The role of shipping temperature as a possible explanation for low sperm viability was explored. We documented that during shipment queens are exposed to temperature spikes (<8 and > 40°C) and these spikes can kill 50% or more of the sperm stored in queen spermathecae in live queens. Clearly low sperm viability is

  15. ECONOMIC GROWTH AND POVERTY,

    DTIC Science & Technology

    that will determine how rapidly we can eliminate poverty in the United States will be the rate of increase in average incomes . And one of the key...The problems of poverty in the United States, and their resolution, are inextricably connected with the nature of the economic growth process and its...economic deprivation, but the adjustments required by growth have left in their wake new pockets of poverty . In the future, one of the key variables

  16. A novel live-dead staining methodology to study malaria parasite viability

    PubMed Central

    2013-01-01

    Background Malaria is a major health and socio-economical problem in tropical and sub-tropical areas of the world. Several methodologies have been used to assess parasite viability during the adaption of field strains to culture or the assessment of drug potential, but these are in general not able to provide an accurate real-time assessment of whether parasites are alive or dead. Methods Different commercial dyes and kits were assessed for their potential to allow for the real-time detection of whether a blood stage malaria parasite is dead or alive. Results Here, a methodology is presented based on the potential-sensitive mitochondrial probe JC-1, which allows for the real-time visualization of live (red staining) and/or dead (absence of red staining) blood stage parasites in vitro and ex vivo. This method is applicable across malaria parasite species and strains and allows to visualize all parasite blood stages including gametocytes. Further, this methodology has been assessed also for use in drug sensitivity testing. Conclusions The JC-1 staining approach is a versatile methodology that can be used to assess parasite viability during the adaptation of field samples to culture and during drug treatment. It was found to hold promise in the assessment of drugs expected to lead to delayed death phenotypes and it currently being evaluated as a method for the assessment of parasite viability during the adaptation of patient-derived Plasmodium vivax to long-term in vitro culture. PMID:23758788

  17. Swarm Economics

    NASA Astrophysics Data System (ADS)

    Kazadi, Sanza; Lee, John

    The Hamiltonian Method of Swarm Design is applied to the design of an agent based economic system. The method allows the design of a system from the global behaviors to the agent behaviors, with a guarantee that once certain derived agent-level conditions are satisfied, the system behavior becomes the desired behavior. Conditions which must be satisfied by consumer agents in order to bring forth the `invisible hand of the market' are derived and demonstrated in simulation. A discussion of how this method might be extended to other economic systems and non-economic systems is presented.

  18. Viability and Virulence of Entomopathogenic Nematodes Exposed to Ultraviolet Radiation

    PubMed Central

    Shapiro-Ilan, David I.; Hazir, Selcuk; Lete, Luis

    2015-01-01

    Entomopathogenic nematodes (EPNs) can be highly effective biocontrol agents, but their efficacy can be reduced due to exposure to environmental stress such as from ultraviolet (UV) radiation. Our objectives were to 1) compare UV tolerance among a broad array of EPN species, and 2) investigate the relationship between reduced nematode viability (after exposure to UV) and virulence. Nematodes exposed to a UV radiation (254 nm) for 10 or 20 min were assessed separately for viability (survival) and virulence to Galleria mellonella. We compared 9 different EPN species and 15 strains: Heterorhabditis bacteriophora (Baine, fl11, Oswego, and Vs strains), H. floridensis (332), H. georgiana (Kesha), H. indica (HOM1), H. megidis (UK211), Steinernema carpocapsae (All, Cxrd, DD136, and Sal strains), S. feltiae (SN), S. rarum (17C&E), and S. riobrave (355). In viability assessments, steinernematids, particularly strains of S. carpocapsae, generally exhibited superior UV tolerance compared with the heterorhabditids. However, some heterorhabditids tended to be more tolerant than others, e.g., H. megidis and H. bacteriophora (Baine) were most susceptible and H. bacteriophora (Vs) was the only heterorhabditid that did not exhibit a significant effect after 10 min of exposure. All heterorhabditids experienced reduced viability after 20 min exposure though several S. carpocapsae strains did not. In total, after 10 or 20 min exposure, the viability of seven nematode strains did not differ from their non-UV exposed controls. In virulence assays, steinernematids (particularly S. carpocapsae strains) also tended to exhibit higher UV tolerance. However, in contrast to the viability measurements, all nematodes experienced a reduction in virulence relative to their controls. Correlation analysis revealed that viability among nematode strains is not necessarily related to virulence. In conclusion, our results indicate that the impact of UV varies substantially among EPNs, and viability alone

  19. Enhanced cell viability and cell adhesion using low conductivity medium for negative dielectrophoretic cell patterning.

    PubMed

    Puttaswamy, Srinivasu Valagerahally; Sivashankar, Shilpa; Chen, Rong-Jhe; Chin, Chung-Kuang; Chang, Hwan-You; Liu, Cheng Hsien

    2010-10-01

    Negative dielectrophoretic (n-DEP) cell manipulation is an efficient way to pattern human liver cells on micro-electrode arrays. Maintaining cell viability is an important objective for this approach. This study investigates the effect of low conductivity medium and the optimally designed microchip on cell viability and cell adhesion. To explore the influence of conductivity on cell viability and cell adhesion, we have used earlier reported dielectrophoresis (DEP) buffer with a conductivity of 10.2 mS/m and three formulated media with conductivity of 9.02 (M1), 8.14 (M2), 9.55 (M3) mS/m. The earlier reported isotonic sucrose/dextrose buffer (DEP buffer) used for DEP manipulation has the drawback of poor cell adhesion and cell viability. A microchip prototype with well-defined positioning of titanium electrode arrays was designed and fabricated on a glass substrate. The gap between the radial electrodes was accurately determined to achieve good cell patterning performance. Parameters such as dimension of positioning electrode, amplitude, and frequency of voltage signal were investigated to optimize the performance of the microchip.

  20. A study of different buffers to maximize viability of an oral Shigella vaccine.

    PubMed

    Chandrasekaran, Lakshmi; Lal, Manjari; Van De Verg, Lillian L; Venkatesan, Malabi M

    2015-11-17

    Live, whole cell killed and subunit vaccines are being developed for diarrheal diseases caused by V. cholerae, Shigella species, ETEC, and Campylobacter. Some of these vaccines can be administered orally since this route best mimics natural infection. Live vaccines administered orally have to be protected from the harsh acidic gastric environment. Milk and bicarbonate solutions have been administered to neutralize the stomach acid. For many Shigella vaccine trials, 100-120 ml of a bicarbonate solution is ingested followed by the live vaccine candidate, which is delivered in 30 ml of bicarbonate, water or saline. It is not clear if maximum bacterial viability is achieved under these conditions. Also, volumes of neutralizing buffer that are optimal for adults may be unsuitable for children and infants. To address these questions, we performed studies to determine the viability and stability of a Shigella sonnei vaccine candidate, WRSS1, in a mixture of different volumes of five different buffer solutions added to hydrochloric acid to simulate gastric acidity. Among the buffers tested, bicarbonate solution, rotavirus buffer and CeraVacx were better at neutralizing acid and maintaining the viability of WRSS1. Also, a much smaller volume of the neutralizing buffer was sufficient to counteract stomach acid while maintaining bacterial viability.

  1. Dynamic changes in Mcl-1 expression regulate macrophage viability or commitment to apoptosis during bacterial clearance.

    PubMed

    Marriott, Helen M; Bingle, Colin D; Read, Robert C; Braley, Karen E; Kroemer, Guido; Hellewell, Paul G; Craig, Ruth W; Whyte, Moira K B; Dockrell, David H

    2005-02-01

    Macrophages are critical effectors of bacterial clearance and must retain viability, despite exposure to toxic bacterial products, until key antimicrobial functions are performed. Subsequently, host-mediated macrophage apoptosis aids resolution of infection. The ability of macrophages to make this transition from resistance to susceptibility to apoptosis is important for effective host innate immune responses. We investigated the role of Mcl-1, an essential regulator of macrophage lifespan, in this switch from viability to apoptosis, using the model of pneumococcal-associated macrophage apoptosis. Upon exposure to pneumococci, macrophages initially upregulate Mcl-1 protein and maintain viability for up to 14 hours. Subsequently, macrophages reduce expression of full-length Mcl-1 and upregulate a 34-kDa isoform of Mcl-1 corresponding to a novel BH3-only splice variant, Mcl-1(Exon-1). Change in expression of Mcl-1 protein is associated with mitochondrial membrane permeabilization, which is characterized by loss of mitochondrial inner transmembrane potential and translocation of cytochrome c and apoptosis-inducing factor. Following pneumococcal infection, macrophages expressing full-length human Mcl-1 as a transgene exhibit a delay in apoptosis and in bacterial killing. Mcl-1 transgenic mice clear pneumococci from the lung less efficiently than nontransgenic mice. Dynamic changes in Mcl-1 expression determine macrophage viability as well as antibacterial host defense.

  2. Sperm morphometry: a tool for detecting biophysical changes associated with viability in cryopreserved bovine spermatozoa.

    PubMed

    García-Herreros, M; Leal, C L V

    2014-09-01

    The aim of this study was to determine whether computerised sperm head morphometric analysis can be used as a diagnostic tool for detecting biophysical changes associated with sperm viability in frozen-thawed bovine spermatozoa. Ejaculates from five bulls (4 ejaculates/bull) were pooled and processed for computerised morphometric analysis, and SYBR-14 green/ethidium homodimer-1 fluorescence-based live/dead viability assay was used simultaneously to confirm the viability index of frozen-thawed spermatozoa. Sperm samples were assigned to three experimental groups. The first group was enriched in live spermatozoa (after a double Percoll selection), the second group was enriched in dead spermatozoa (after a refreeze-thaw procedure), and the last group was a 50 : 50 pool of live/dead spermatozoa (from first and second group samples). There were significant differences (P < 0.001) related to sperm morphometric dimensional parameters among the three groups analysed, being the lowest overall sperm head dimension found in the second (dead spermatozoa) group. In conclusion, sperm head morphometry can be used as a potential diagnostic tool for detecting biophysical changes associated with sperm viability in frozen-thawed bovine spermatozoa.

  3. The effects of six root-end filling materials and their leachable components on cell viability.

    PubMed

    Al-Sa'eed, Oula R; Al-Hiyasat, Ahmad S; Darmani, Homa

    2008-11-01

    This study investigated the effect of six root-end filling materials (Retroplast [Retroplast Trading, Dybesøvej, Denmark], Geristore, [DEN-MAT Corporation, Santa Maria, CA], Ketac Fil [3M ESPE, Seefeld, Germany], IRM [Caulk-Dentsply, Milford, DE], Super EBA [Bosworth Company, Skokie, IL], and MTA [Dentsply-Tulsa Dental, Johnson City, TN]) on the viability of Balb/C 3T3 fibroblasts using the [3-4, 5-dimethyl thiazol-2-yl]-2,5-diphenyl tetrazolium bromide succinate (MTT) assay. Ten discs (5 mm x 2 mm) of each material were eluted in tissue culture medium for 24 hours at 37 degrees C for 3 successive days and the elutes used for cell viability testing and for determination of leached components. The results showed that Retroplast, Geristore, and Ketac Fil increased cell proliferation, whereas Super-EBA decreased cell viability. The proliferative effect of Retroplast and Geristore increased with the eluting time (24 hours, 48 hours, and 72 hours), whereas the effects of the other materials did not significantly change. IRM and MTA did not affect cell viability. High-performance liquid chromatography analysis and atomic absorption spectroscopy showed that there was variation in the amount of leached components from the materials. Our results indicate that the reaction of cells to root-end filling materials varies considerably between materials.

  4. Imatinib alters cell viability but not growth factors levels in TM4 Sertoli cells

    PubMed Central

    Hashemnia, Seyyed Mohammad Reza; Atari-Hajipirloo, Somayeh; Roshan-Milani, Shiva; Valizadeh, Nasim; Mahabadi, Sonya; Kheradmand, Fatemeh

    2016-01-01

    Background: The anticancer agent imatinib (IM) is a small molecular analog of ATP that inhibits tyrosine kinase activity of platelet derived growth factors (PDGFs) and stem cell factor (SCF) receptor in cancer cells. However these factors have a key role in regulating growth and development of normal Sertoli, Leydig and germ cells. Objective: The aim of this study was to determine cell viability, PDGF and SCF levels in mouse normal Sertoli cells exposed to IM. Materials and Methods: In this experimental study, the mouse TM4 Sertoli cells were treated with 0, 2.5, 5, 10 and 20 μM IM for 2, 4 or 6 days. The cell viability and growth factors levels were assessed by MTT and ELISA methods, respectively. For statistical analysis, One-Way ANOVA was performed. Results: IM showed significant decrease in Sertoli cell viability compared to control group (p=0.001). However, IM increased PDGF and SCF level insignificantly (p>0.05). Conclusion: Results suggested that IM treatment induced a dose dependent reduction of cell viability in Sertoli cells. It seems that treatment with this anticancer drug is involved in the fertility process. Further studies are needed to evaluate the role of PDGF and SCF in this cell. PMID:27738659

  5. Economic Evaluation of Single-Family-Residence Solar-Energy Installation

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Long-term economic performance of a commercial solar-energy system was analyzed and used to predict economic performance at four additional sites. Analysis described in report was done to demonstrate viability of design over a broad range of environmental/economic conditions. Report contains graphs and tables that present evaluation procedure and results. Also contains appendixes that aid in understanding methods used.

  6. Using Bayesian Population Viability Analysis to Define Relevant Conservation Objectives

    PubMed Central

    Green, Adam W.; Bailey, Larissa L.

    2015-01-01

    Adaptive management provides a useful framework for managing natural resources in the face of uncertainty. An important component of adaptive management is identifying clear, measurable conservation objectives that reflect the desired outcomes of stakeholders. A common objective is to have a sustainable population, or metapopulation, but it can be difficult to quantify a threshold above which such a population is likely to persist. We performed a Bayesian metapopulation viability analysis (BMPVA) using a dynamic occupancy model to quantify the characteristics of two wood frog (Lithobates sylvatica) metapopulations resulting in sustainable populations, and we demonstrate how the results could be used to define meaningful objectives that serve as the basis of adaptive management. We explored scenarios involving metapopulations with different numbers of patches (pools) using estimates of breeding occurrence and successful metamorphosis from two study areas to estimate the probability of quasi-extinction and calculate the proportion of vernal pools producing metamorphs. Our results suggest that ≥50 pools are required to ensure long-term persistence with approximately 16% of pools producing metamorphs in stable metapopulations. We demonstrate one way to incorporate the BMPVA results into a utility function that balances the trade-offs between ecological and financial objectives, which can be used in an adaptive management framework to make optimal, transparent decisions. Our approach provides a framework for using a standard method (i.e., PVA) and available information to inform a formal decision process to determine optimal and timely management policies. PMID:26658734

  7. Scaffold architecture controls insulinoma clustering, viability, and insulin production.

    PubMed

    Blackstone, Britani N; Palmer, Andre F; Rilo, Horacio R; Powell, Heather M

    2014-07-01

    Recently, in vitro diagnostic tools have shifted focus toward personalized medicine by incorporating patient cells into traditional test beds. These cell-based platforms commonly utilize two-dimensional substrates that lack the ability to support three-dimensional cell structures seen in vivo. As monolayer cell cultures have previously been shown to function differently than cells in vivo, the results of such in vitro tests may not accurately reflect cell response in vivo. It is therefore of interest to determine the relationships between substrate architecture, cell structure, and cell function in 3D cell-based platforms. To investigate the effect of substrate architecture on insulinoma organization and function, insulinomas were seeded onto 2D gelatin substrates and 3D fibrous gelatin scaffolds with three distinct fiber diameters and fiber densities. Cell viability and clustering was assessed at culture days 3, 5, and 7 with baseline insulin secretion and glucose-stimulated insulin production measured at day 7. Small, closely spaced gelatin fibers promoted the formation of large, rounded insulinoma clusters, whereas monolayer organization and large fibers prevented cell clustering and reduced glucose-stimulated insulin production. Taken together, these data show that scaffold properties can be used to control the organization and function of insulin-producing cells and may be useful as a 3D test bed for diabetes drug development.

  8. Decreased winter severity increases viability of a montane frog population

    PubMed Central

    McCaffery, Rebecca M.; Maxell, Bryce A.

    2010-01-01

    Many proximate causes of global amphibian declines have been well documented, but the role that climate change has played and will play in this crisis remains ambiguous for many species. Breeding phenology and disease outbreaks have been associated with warming temperatures, but, to date, few studies have evaluated effects of climate change on individual vital rates and subsequent population dynamics of amphibians. We evaluated relationships among local climate variables, annual survival and fecundity, and population growth rates from a 9-year demographic study of Columbia spotted frogs (Rana luteiventris) in the Bitterroot Mountains of Montana. We documented an increase in survival and breeding probability as severity of winter decreased. Therefore, a warming climate with less severe winters is likely to promote population viability in this montane frog population. More generally, amphibians and other ectotherms inhabiting alpine or boreal habitats at or near their thermal ecological limits may benefit from the milder winters provided by a warming climate as long as suitable habitats remain intact. A more thorough understanding of how climate change is expected to benefit or harm amphibian populations at different latitudes and elevations is essential for determining the best strategies to conserve viable populations and allow for gene flow and shifts in geographic range. PMID:20421473

  9. Using the pollen viability and morphology for fluoride pollution biomonitoring.

    PubMed

    Malayeri, Behrooz Eshghi; Noori, Mitra; Jafari, Mehrana

    2012-06-01

    The methods using plants for biomonitoring of air and soil quality are simple, cheap, and fast and can supplement the classical physicochemical methods. In this study, biological pollen characterization of some collected legume species from an aluminum smelter area in Iran (IRALCO) was carried out to determine the actual value of pollen as a bioindicator of the effects of soil and atmospheric pollution. Young buds and flowers of six legumes (Cercis siliquastrum L., Medicago sativa L., Robinia pseudoacacia L., Melilotus officinalis (L.) lam, Trifolium repens L., and Sophora alopecuroides L.) in polluted and control plants were removed and compared. Studies of light and electron microscopic preparation showed some abnormalities during pollen development in affect of fluoride pollution. The viability of pollen grains estimated by staining with acetocarmine shows sharp differences in smearing advanced pollen grains from abnormal ones. Except M. officinalis, the pollen grains of C. siliquastrum, M. sativa, R. pseudoacacia, T. repens, and S. alopecuroides in polluted areas showed light, partial, or no staining with acetocarmine, whereas almost all of the control ones clearly stained. Observation of the pollen grains by light microscopy and scanning electron microscopy showed the significant effect of fluoride on shapes and sizes of pollen grains. The stimulation and inhibition of these pollen characteristics depend on the pollen species as well as on the pollutant and its concentration. Therefore, pollen grains provide essential information on biological impact of pollutants and they are good candidates for biomonitoring the atmospheric and edaphic pollutions.

  10. Assessment of viability of the nematode eggs (Ascaris, Toxocara, Trichuris) in sewage sludge with the use of LIVE/DEAD Bacterial Viability Kit.

    PubMed

    Dąbrowska, Joanna; Zdybel, Jolanta; Karamon, Jacek; Kochanowski, Maciej; Stojecki, Krzysztof; Cencek, Tomasz; Kłapeć, Teresa

    2014-01-01

    Sewage sludges from wastewater treatment plants may contain live parasite eggs, which can be a source of humans and animals infection. According to the current rules, parasitological examination includes detection of the Ascaris spp., Trichuris spp. and Toxocara spp. eggs and estimation of their viability. The viability assessment based only on the incubation and observation of isolated egg is long and imprecise. The aim of this study was to develop sensitive and less labour-intensive methods for assessing viability of Ascaris spp., Toxocara spp. and Trichuris spp. eggs in sewage sludge. For this purpose, LIVE/DEAD Kit was used. Firstly, the possibility of distinguishing between live and dead eggs in water was assessed. Secondly, an appropriate amount of dyeing mixture needed to distinguish the live and dead eggs in the sewage sludge was determined using experimentally enriched samples and naturally contaminated samples of sludge. Eggs were isolated from the samples by own method which was a combination of flotation and sedimentation, preceded by a long mixing. After the last stage of the procedure, sediment containing the eggs of parasites was stained by LIVE/DEAD kit according to the manufacturer instructions, but with the use of different variants of dyes mixture concentration. The investigation showed that live and dead eggs of these three parasites could be differed by this method with the use of proper concentration of dyes. Live eggs were stained in green (Ascaris and Trichuris) and green-blue (Toxocara). However, all types of dead eggs were red coloured. The study demonstrated that after some modifications (resulted from the nature of the samples) the LIVE/DEAD kit is useful for assessing the viability of Toxocara, Ascaris and Trichuris eggs occurring in the sludge.

  11. 24 CFR 971.5 - Long-term viability.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... ASSESSMENT OF THE REASONABLE REVITALIZATION POTENTIAL OF CERTAIN PUBLIC HOUSING REQUIRED BY LAW § 971.5 Long... ensure viability and to sustain the operating costs that are described in paragraph (a)(2) of...

  12. 24 CFR 971.5 - Long-term viability.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... ASSESSMENT OF THE REASONABLE REVITALIZATION POTENTIAL OF CERTAIN PUBLIC HOUSING REQUIRED BY LAW § 971.5 Long... ensure viability and to sustain the operating costs that are described in paragraph (a)(2) of...

  13. 24 CFR 971.5 - Long-term viability.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... ASSESSMENT OF THE REASONABLE REVITALIZATION POTENTIAL OF CERTAIN PUBLIC HOUSING REQUIRED BY LAW § 971.5 Long... ensure viability and to sustain the operating costs that are described in paragraph (a)(2) of...

  14. Probiotic fermented sausage: viability of probiotic microorganisms and sensory characteristics.

    PubMed

    Rouhi, M; Sohrabvandi, S; Mortazavian, A M

    2013-01-01

    Probiotics are from functional foods that bring health benefits for humans. Nowadays, a major development in functional foods is related to food containing probiotic cultures, mainly lactic acid bacteria or bifidobacteria. Probiotics must be alive and ingested in sufficient amounts to exert the positive effects on the health and the well-being of the host. Therefore, viability of probiotic products (the minimum viable probiotic cells in each gram or milliliter of product till the time of consumption) is their most important characteristic. However, these organisms often show poor viability in fermented products due to their detrimental conditions. Today, the variety of fermented meat products available around the world is nearly equal to that of cheese. With meat products, raw fermented sausages could constitute an appropriate vehicle for such microorganisms into the human gastrointestinal tract. In present article, the viability of probiotic microorganisms in fermented sausage, the main factors affect their viability, and the sensorial characteristics of final product are discussed.

  15. Socio-economic factors, gender and smoking as determinants of COPD in a low-income country of sub-Saharan Africa: FRESH AIR Uganda

    PubMed Central

    van Gemert, Frederik; Chavannes, Niels; Kirenga, Bruce; Jones, Rupert; Williams, Sian; Tsiligianni, Ioanna; Vonk, Judith; Kocks, Janwillem; de Jong, Corina; van der Molen, Thys

    2016-01-01

    In Uganda, biomass smoke seems to be the largest risk factor for the development of COPD, but socio-economic factors and gender may have a role. Therefore, more in-depth research is needed to understand the risk factors. The aim of this study was to investigate the impact of socio-economic factors and gender differences on the COPD prevalence in Uganda. The population comprised 588 randomly selected participants (>30 years) who previously completed the FRESH AIR Uganda study. In this post hoc analysis, the impact of several socio-economic characteristics, gender and smoking on the prevalence of COPD was assessed using a logistic regression model. The main risk factors associated with COPD were non-Bantu ethnicity (odds ratio (OR) 1.73, 95% confidence interval (CI) 1.06–2.82, P=0.030), biomass fuel use for heating (OR 1.76, 95% CI 1.03–3.00, P=0.038), former smoker (OR 1.87, 95% CI 0.97–3.60, P=0.063) and being unmarried (OR 0.087, 95% CI 0.93–2.95, P=0.087). A substantial difference in the prevalence of COPD was seen between the two ethnic groups: non-Bantu 20% and Bantu 12.9%. Additional analysis between these two groups showed significant differences in socio-economic circumstances: non-Bantu people smoked more (57.7% vs 10.7%), lived in tobacco-growing areas (72% vs 14.8%) and were less educated (28.5% vs 12.9% had no education). With regard to gender, men with COPD were unmarried (OR 3.09, 95% CI 1.25–7.61, P=0.015) and used more biomass fuel for heating (OR 2.15, 95% CI 1.02–4.54, P=0.045), and women with COPD were former smokers (OR 3.35, 95% CI 1.22–9.22, P=0.019). Only a few socio-economic factors (i.e., smoking, biomass fuel use for heating, marital status and non-Bantu ethnicity) have been found to be associated with COPD. This applied for gender differences as well (i.e., for men, marital status and biomass fuel for heating, and for women being a former smoker). More research is needed to clarify the complexity of the different risk factors

  16. Non-destructive monitoring of viability in an ex vivo organ culture model of osteochondral tissue.

    PubMed

    Elson, K M; Fox, N; Tipper, J L; Kirkham, J; Hall, R M; Fisher, J; Ingham, E

    2015-06-30

    Organ culture is an increasingly important tool in research, with advantages over monolayer cell culture due to the inherent natural environment of tissues. Successful organ cultures must retain cell viability. The aim of this study was to produce viable and non-viable osteochondral organ cultures, to assess the accumulation of soluble markers in the conditioned medium for predicting tissue viability. Porcine femoral osteochondral plugs were cultured for 20 days, with the addition of Triton X-100 on day 6 (to induce necrosis), camptothecin (to induce apoptosis) or no toxic additives. Tissue viability was assessed by the tissue destructive XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxyanilide tetrazolium salt) assay method and LIVE/DEAD® staining of the cartilage at days 0, 6 and 20. Tissue structure was assessed by histological evaluation using haematoxylin & eosin and safranin O. Conditioned medium was assessed every 3-4 days for glucose depletion, and levels of lactate dehydrogenase (LDH), alkaline phosphatase (AP), glycosaminoglycans (GAGs), and matrix metalloproteinase (MMP)-2 and MMP-9. Necrotic cultures immediately showed a reduction in glucose consumption, and an immediate increase in LDH, GAG, MMP-2 and MMP-9 levels. Apoptotic cultures showed a delayed reduction in glucose consumption and delayed increase in LDH, a small rise in MMP-2 and MMP-9, but no significant effect on GAGs released into the conditioned medium. The data showed that tissue viability could be monitored by assessing the conditioned medium for the aforementioned markers, negating the need for tissue destructive assays. Physiologically relevant whole- or part-joint organ culture models, necessary for research and pre-clinical assessment of therapies, could be monitored this way, reducing the need to sacrifice tissues to determine viability, and hence reducing the sample numbers necessary.

  17. Ovarian Fluid Mediates the Temporal Decline in Sperm Viability in a Fish with Sperm Storage

    PubMed Central

    Gasparini, Clelia; Evans, Jonathan P.

    2013-01-01

    A loss of sperm viability and functionality during sperm transfer and storage within the female reproductive tract can have important fitness implications by disrupting fertilization and impairing offspring development and survival. Consequently, mechanisms that mitigate the temporal decline in sperm function are likely to be important targets of selection. In many species, ovarian fluid is known to regulate and maintain sperm quality. In this paper, we use the guppy Poecilia reticulata, a highly polyandrous freshwater fish exhibiting internal fertilization and sperm storage, to determine whether ovarian fluid (OF) influences the decline in sperm viability (the proportion of live sperm in the ejaculate) over time and whether any observed effects depend on male sexual ornamentation. To address these questions we used a paired experimental design in which ejaculates from individual males were tested in vitro both in presence and absence of OF. Our results revealed that the temporal decline in sperm viability was significantly reduced in the presence of OF compared to a saline control. This finding raises the intriguing possibility that OF may play a role in mediating the decline in sperm quality due to the deleterious effects of sperm ageing, although other possible explanations for this observation are discussed. Interestingly, we also show that the age-related decline in sperm viability was contingent on male sexual ornamentation; males with relatively high levels of iridescence (indicating higher sexual attractiveness) exhibited a more pronounced decline in sperm viability over time than their less ornamented counterparts. This latter finding offers possible insights into the functional basis for the previously observed trade-off between these key components of pre- and postcopulatory sexual selection. PMID:23691216

  18. Solar energy system economic evaluation: Fern Tunkhannock, Tunkhannock, Pennsylvania. Final report

    SciTech Connect

    Not Available

    1980-09-01

    The economic performance of an Operational Test Site (OTS) is described. The long term economic performance of the system at its installation site and extrapolation to four additional selected locations to demonstrate the viability of the design over a broad range of environmental and economic conditions is reported. Topics discussed are: system description, study approach, economic analysis and system optimization, and technical and economical results of analysis. Data for the economic analysis are generated through evaluation of the OTS. The simulation is based on the technical results of the seasonal report simulation. In addition localized and standard economic parameters are used for economic analysis.

  19. 30 CFR 203.85 - What is in an economic viability and relief justification report?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... “Guidelines for the Application, Review, Approval and Administration of the Deep Water Royalty Relief Program...) Transportation costs; and (6) Before-tax net cash flow without royalties, overrides, sunk costs, and ineligible... specify). (2) Before-tax net present value without royalties, overrides, sunk costs, and ineligible...

  20. 30 CFR 203.85 - What is in an economic viability and relief justification report?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... “Guidelines for the Application, Review, Approval and Administration of the Deep Water Royalty Relief Program...) Transportation costs; and (6) Before-tax net cash flow without royalties, overrides, sunk costs, and ineligible... specify). (2) Before-tax net present value without royalties, overrides, sunk costs, and ineligible...

  1. 30 CFR 203.85 - What is in an economic viability and relief justification report?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... specify are found in the “Guidelines for the Application, Review, Approval and Administration of the Deep...) Operating costs; (5) Transportation costs; and (6) Before-tax net cash flow without royalties, overrides... from within the range we specify). (2) Before-tax net present value without royalties, overrides,...

  2. 30 CFR 203.85 - What is in an economic viability and relief justification report?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... “Guidelines for the Application, Review, Approval and Administration of the Deep Water Royalty Relief Program...) Transportation costs; and (6) Before-tax net cash flow without royalties, overrides, sunk costs, and ineligible... specify). (2) Before-tax net present value without royalties, overrides, sunk costs, and ineligible...

  3. Origins, characteristics, controls, and economic viabilities of deep- basin gas resources

    USGS Publications Warehouse

    Price, L.C.

    1995-01-01

    Dry-gas deposits (methane ???95% of the hydrocarbon (HC) gases) are thought to originate from in-reservoir thermal cracking of oil and C2+ HC gases to methane. However, because methanes from Anadarko Basin dry-gas deposits do not carry the isotopic signature characteristics of C15+ HC destruction, an origin of these methanes from this process is considered improbable. Instead, the isotopic signature of these methanes suggests that they were cogenerated with C15+ HC's. Only a limited resource of deep-basin gas deposits may be expected by the accepted model for the origin of dry-gas deposits because of a limited number of deep-basin oil deposits originally available to be thermally converted to dry gas. However, by the models of this paper (inefficient source-rock oil and gas expulsion, closed fluid systems in petroleum-basin depocenters, and most dry-gas methane cogenerated with C15+ HC's), very large, previously unrecognized, unconventional, deep-basin gas resources are expected. -from Author

  4. Enhancing the economic viability of pastoralism: the need to balance interventions.

    PubMed

    Rueff, H; Rahim, I

    2016-11-01

    Extensive mobile pastoral systems do not follow conventional marketing optimisation models, since they must deal with the factors of mobility, erratic environments, dependency on natural resources, seasonality, and distance to markets. While pastoralist systems contribute substantially to national economies, government investment to support pastoralism remains limited or non-existent. Pastoralists are becoming increasingly integrated into larger market systems and therefore need investment and specially adapted policies to supply a growing demand for livestock products and to support their livelihoods. In this paper, the authors show that investment and technology can support and empower pastoralist marketing strategies in supplying higher-value and more stable livestock products. Furthermore, the authors demonstrate that pastoralists also supply services, broadening the marketing landscape within which they operate to include more players and trading options. Pastoralists are undeniably the custodians of rangelands and provide a wide range of ecosystem services. These new market prospects nevertheless require structuring (e.g. regulation, infrastructure) and adjustments in the trading environment of stakeholders all along the value chain. There is, however, an inherent risk in intervening in pastoral marketing and production processes. Too many or ill-adapted interventions can have severe effects on these systems, resulting in over-intensification and reduced mobility. Finding the right level of intervention to support extensive pastoral systems is important when developing policy, since it is about the only form of land use that can keep a third of the world's land surface in food production without additional inputs.

  5. Consensus among Economics Teachers from Transition Economies

    ERIC Educational Resources Information Center

    Leet, Don R.; Lang, Nancy A.

    2010-01-01

    The authors analyze the economic opinions of teachers and economists from the former Soviet Union who participated in economic education programs sponsored by the U.S. Department of Education under the auspices of the National Council on Economic Education from 1995-2001. They sought to determine the level of consensus on economic topics among the…

  6. Growth habit and leaf economics determine gas exchange responses to high elevation in an evergreen tree, a deciduous shrub and a herbaceous annual

    PubMed Central

    Shi, Zuomin; Haworth, Matthew; Feng, Qiuhong; Cheng, Ruimei; Centritto, Mauro

    2015-01-01

    Plant growth at high elevations necessitates physiological and morphological plasticity to enable photosynthesis (A) under conditions of reduced temperature, increased radiation and the lower partial pressure of atmospheric gases, in particular carbon dioxide (pCO2). Previous studies have observed a wide range of responses to elevation in plant species depending on their adaptation to temperature, elevational range and growth habit. Here, we investigated the effect of an increase in elevation from 2500 to 3500 m above sea level (a.s.l.) on three montane species with contrasting growth habits and leaf economic strategies. While all of the species showed identical increases in foliar δ13C, dark respiration and nitrogen concentration with elevation, contrasting leaf gas exchange and photosynthetic responses were observed between species with different leaf economic strategies. The deciduous shrub Salix atopantha and annual herb Rumex dentatus exhibited increased stomatal (Gs) and mesophyll (Gm) conductance and enhanced photosynthetic capacity at the higher elevation. However, evergreen Quercus spinosa displayed reduced conductance to CO2 that coincided with lower levels of photosynthetic carbon fixation at 3500 m a.s.l. The lower Gs and Gm values of evergreen species at higher elevations currently constrains their rates of A. Future rises in the atmospheric concentration of CO2 ([CO2]) will likely predominantly affect evergreen species with lower specific leaf areas (SLAs) and levels of Gm rather than deciduous species with higher SLA and Gm values. We argue that climate change may affect plant species that compose high-elevation ecosystems differently depending on phenotypic plasticity and adaptive traits affecting leaf economics, as rising [CO2] is likely to benefit evergreen species with thick sclerophyllous leaves. PMID:26433706

  7. Growth habit and leaf economics determine gas exchange responses to high elevation in an evergreen tree, a deciduous shrub and a herbaceous annual.

    PubMed

    Shi, Zuomin; Haworth, Matthew; Feng, Qiuhong; Cheng, Ruimei; Centritto, Mauro

    2015-10-03

    Plant growth at high elevations necessitates physiological and morphological plasticity to enable photosynthesis (A) under conditions of reduced temperature, increased radiation and the lower partial pressure of atmospheric gases, in particular carbon dioxide (pCO2). Previous studies have observed a wide range of responses to elevation in plant species depending on their adaptation to temperature, elevational range and growth habit. Here, we investigated the effect of an increase in elevation from 2500 to 3500 m above sea level (a.s.l.) on three montane species with contrasting growth habits and leaf economic strategies. While all of the species showed identical increases in foliar δ(13)C, dark respiration and nitrogen concentration with elevation, contrasting leaf gas exchange and photosynthetic responses were observed between species with different leaf economic strategies. The deciduous shrub Salix atopantha and annual herb Rumex dentatus exhibited increased stomatal (Gs) and mesophyll (Gm) conductance and enhanced photosynthetic capacity at the higher elevation. However, evergreen Quercus spinosa displayed reduced conductance to CO2 that coincided with lower levels of photosynthetic carbon fixation at 3500 m a.s.l. The lower Gs and Gm values of evergreen species at higher elevations currently constrains their rates of A. Future rises in the atmospheric concentration of CO2 ([CO2]) will likely predominantly affect evergreen species with lower specific leaf areas (SLAs) and levels of Gm rather than deciduous species with higher SLA and Gm values. We argue that climate change may affect plant species that compose high-elevation ecosystems differently depending on phenotypic plasticity and adaptive traits affecting leaf economics, as rising [CO2] is likely to benefit evergreen species with thick sclerophyllous leaves.

  8. Airship economics

    NASA Technical Reports Server (NTRS)

    Neumann, R. D.; Hackney, L. R. M.

    1975-01-01

    Projected operating and manufacturing costs of a large airship design which are considered practical with today's technology and environment are discussed. Data and information developed during an 18-month study on the question of feasibility, engineering, economics and production problems related to a large metalclad type airship are considered. An overview of other classic airship designs are provided, and why metalclad was selected as the most prudent and most economic design to be considered in the 1970-80 era is explained. Crew operation, ATC and enroute requirements are covered along with the question of handling, maintenance and application of systems to the large airship.

  9. Demographic rates and population viability of black bears in Louisiana

    USGS Publications Warehouse

    Laufenberg, Jared S.; Clark, Joseph D.; Hooker, Michael J.; Lowe, Carrie L.; O'Connell-Goode, Kaitlin C.; Troxler, Jesse C.; Davidson, Maria M.; Chamberlain, Michael J.; Chandler, Richard B.

    2015-01-01

    observed 43 yearling litters for 33 females in the TRB and 21 yearling litters for 19 females in the TRC. The estimated number of cubs and number of yearlings produced per breeding adult female was 0.47 and 0.20, respectively, in the TRB and 0.32 and 0.18 in the TRC. On the basis of matrix projection models, asymptotic growth rates ranged from 1.053 to 1.078 for the TRB and from 1.005 to 1.062 for the TRC, depending on how we treated unresolved fates of adult females. Persistence probabilities estimated from stochastic population models based on telemetry data ranged from 0.997 to 0.998 for the TRC subpopulation depending on model assumptions and were >0.999 for the TRB regardless of model assumptions. We extracted DNA from hair collected at baited, barbed-wire enclosures in the TRB, UARB, and LARB to determine individual identities for capture-mark-recapture (CMR) analysis. We used those detection histories to estimate apparent survival (φ), per-capita recruitment (f), abundance (N), realized growth rate (λ), and long-term viability, based on Bayesian hierarchical modeling methods that allowed estimation of temporal process variance and parameter uncertainty. Based on 23,312 hair samples, annual N for females in the TRB ranged from 133 to 164 during 2006–2012, depending on year and how detection heterogeneity was modeled. Geometric mean of λ ranged from 0.996 to 1.002. In the UARB, we collected 11,643 hair samples from 2007 to 2012, from which estimates of N for females ranged from 23 to 43 during the study period, depending on detection heterogeneity model. The geometric mean of λ ranged from 1.038 to 1.059. Estimated N for females in LARB ranged from 69 to 96, and annual λ ranged from 0.80 to 1.11 based on 3,698 hair samples collected during 2010–2012, also depending on year and heterogeneity model. Probabilities of persistence over 100 years for the TRC and TRB based on stochastic matrix projection models that used vital rate estimates from telemetry data were

  10. Behavioral economics: reunifying psychology and economics.

    PubMed

    Camerer, C

    1999-09-14

    "Behavioral economics" improves the realism of the psychological assumptions underlying economic theory, promising to reunify psychology and economics in the process. Reunification should lead to better predictions about economic behavior and better policy prescriptions.

  11. Crime and Economic Incentives

    ERIC Educational Resources Information Center

    Machin, Stephen; Meghir, Costas

    2004-01-01

    The role that economic incentives play in determining crime rates is explored. A number of experiments were carried out with different wage measures and the result that incentives were the most important factor was reinforced by the strong impact of crime of deterrence measures and of a measure of the returns to crime.

  12. Home Economics.

    ERIC Educational Resources Information Center

    Ontario Dept. of Education, Toronto. School Planning and Building Research Section.

    This presentation of suggested layouts and specifications for home economics facilities has been prepared to be of service to school boards, architects, teachers, and administrators who are planning new schools or making renovations to existing structures. Room layouts are shown for a foods and nutrition room, or the foods and nutrition area of a…

  13. Basketball Economics.

    ERIC Educational Resources Information Center

    Scheinman, Daniel; Scheinman, Ted

    This teaching unit offers five economics lessons related to basketball. Lessons include: (1) "Money, Money, Money in the Basketball Player's World"; (2) "Take Me to the Basketball Game Lesson"; (3) "What Does It Take?"; (4) "Productivity of a Basketball Player"; and (5) "Congratulations! You Just Won…

  14. Economic impact

    SciTech Connect

    Technology Transfer Department

    2001-06-01

    In federal fiscal year 2000 (FY00), Berkeley Lab had 4,347 full- and part-time employees. In addition, at any given time of the year, there were more than 1,000 Laboratory guests. These guests, who also reside locally, have an important economic impact on the nine-county Bay Area. However, Berkeley Lab's total economic impact transcends the direct effects of payroll and purchasing. The direct dollars paid to the Lab's employees in the form of wages, salaries, and benefits, and payments made to contractors for goods and services, are respent by employees and contractors again and again in the local and greater economy. Further, while Berkeley Lab has a strong reputation for basic scientific research, many of the Lab's scientific discoveries and inventions have had direct application in industry, spawning new businesses and creating new opportunities for existing firms. This analysis updates the Economic Impact Analysis done in 1996, and its purpose is to describe the economic and geographic impact of Laboratory expenditures and to provide a qualitative understanding of how Berkeley Lab impacts and supports the local community. It is intended as a guide for state, local, and national policy makers as well as local community members. Unless otherwise noted, this analysis uses data from FY00, the most recent year for which full data are available.

  15. Resource Economics

    NASA Astrophysics Data System (ADS)

    Conrad, Jon M.

    2000-01-01

    Resource Economics is a text for students with a background in calculus, intermediate microeconomics, and a familiarity with the spreadsheet software Excel. The book covers basic concepts, shows how to set up spreadsheets to solve dynamic allocation problems, and presents economic models for fisheries, forestry, nonrenewable resources, stock pollutants, option value, and sustainable development. Within the text, numerical examples are posed and solved using Excel's Solver. These problems help make concepts operational, develop economic intuition, and serve as a bridge to the study of real-world problems of resource management. Through these examples and additional exercises at the end of Chapters 1 to 8, students can make dynamic models operational, develop their economic intuition, and learn how to set up spreadsheets for the simulation of optimization of resource and environmental systems. Book is unique in its use of spreadsheet software (Excel) to solve dynamic allocation problems Conrad is co-author of a previous book for the Press on the subject for graduate students Approach is extremely student-friendly; gives students the tools to apply research results to actual environmental issues

  16. Economic Blues

    ERIC Educational Resources Information Center

    Stuart, Reginald

    2009-01-01

    Today, a national economy gone bust has derailed Black Americans' plans across the country. Gone are many of the economic gains, small as they were, achieved in the post-segregation era by millions of 1960s generation children and their children. Black America today is beset by job losses, business closures, pay cuts, furloughs, investment and…

  17. Cable Economics.

    ERIC Educational Resources Information Center

    Cable Television Information Center, Washington, DC.

    A guide to the economic factors that influence cable television systems is presented. Designed for local officials who must have some familiarity with cable operations in order to make optimum decisions, the guide analyzes the financial framework of a cable system, not only from the operators viewpoint, but also from the perspective of the…

  18. Preliminary report on the commercial viability of gas production from natural gas hydrates

    USGS Publications Warehouse

    Walsh, M.R.; Hancock, S.H.; Wilson, S.J.; Patil, S.L.; Moridis, G.J.; Boswell, R.; Collett, T.S.; Koh, C.A.; Sloan, E.D.

    2009-01-01

    Economic studies on simulated gas hydrate reservoirs have been compiled to estimate the price of natural gas that may lead to economically viable production from the most promising gas hydrate accumulations. As a first estimate, $CDN2005 12/Mscf is the lowest gas price that would allow economically viable production from gas hydrates in the absence of associated free gas, while an underlying gas deposit will reduce the viability price estimate to $CDN2005 7.50/Mscf. Results from a recent analysis of the simulated production of natural gas from marine hydrate deposits are also considered in this report; on an IROR basis, it is $US2008 3.50-4.00/Mscf more expensive to produce marine hydrates than conventional marine gas assuming the existence of sufficiently large marine hydrate accumulations. While these prices represent the best available estimates, the economic evaluation of a specific project is highly dependent on the producibility of the target zone, the amount of gas in place, the associated geologic and depositional environment, existing pipeline infrastructure, and local tariffs and taxes. ?? 2009 Elsevier B.V.

  19. Coiled tubing drilling (CTD) moves to commercial viability

    SciTech Connect

    Romagno, R. ); Walker, R. )

    1994-12-01

    Shell Western E and P, Inc. (SWEPI) California Drilling Operations was interested in coiled tubing (CT) for drilling slimhole steam injectors. A four-well pilot project at South Belridge field, Kern County, Calif., was targeted for immediate CT use. Well programs included completion, a goal not previously attempted on wells drilled from surface with CT. This paper reviews the primary project focus which was to develop slimhole steam injectors and improve injection profiles in lower Tulare formation E and G sands. Feasibility of drilling wells with CT and having CT crews run and cement completion tubulars in place was an issue to be determined. Conventional tubing installation is usually outside the scope of CT operations, so it was not known if this would be technically or economically feasible. Another goal was to refine personnel expertise to further develop CTD services as a successful business line. Other items targeted for investigation were: deviation control; lost circulation solutions; WOB optimization to obtain maximum ROP; potential steam blowout intervals; and high temperature. Finally, economic feasibility of using CTD as a rotary rig alternative for specific applications like slimhole wells on sites where surface location is limited was to be determined.

  20. Optimizing conservation strategies for Mexican freetailed bats: a population viability and ecosystem services approach

    USGS Publications Warehouse

    Wiederholt, Ruscena; Lopez-Hoffman, Laura; Svancara, Colleen; McCracken, Gary; Thogmartin, Wayne E.; Diffendorfer, James E.; Mattson, Brady; Bagstad, Kenneth J.; Cryan, Paul; Amy Russell,; Semmens, Darius J.; Rodrigo A. Medellín,

    2015-01-01

    Conservation planning can be challenging due to the need to balance biological concerns about population viability with social concerns about the benefits biodiversity provide to society, often while operating under a limited budget. Methods and tools that help prioritize conservation actions are critical for the management of at-risk species. Here, we use a multi-attribute utility function to assess the optimal maternity roosts to conserve for maintaining the population viability and the ecosystem services of a single species, the Mexican free-tailed bat (Tadarida brasiliensis mexicana). Mexican free-tailed bats provide ecosystem services such as insect pest-suppression in agricultural areas and recreational viewing opportunities, and may be threatened by climate change and development of wind energy. We evaluated each roost based on five attributes: the maternity roost’s contribution to population viability, the pest suppression ecosystem services to the surrounding area provided by the bats residing in the roost, the ecotourism value of the roost, the risks posed to each roost structure, and the risks posed to the population of bats residing in each roost. We compared several scenarios that prioritized these attributes differently, hypothesizing that the set of roosts with the highest rankings would vary according to the conservation scenario. Our results indicate that placing higher values on different roost attributes (e.g. population importance over ecosystem service value) altered the roost rankings. We determined that the values placed on various conservation objectives are an important determinant of habitat planning.

  1. Effects of acetic acid on the viability of Ascaris lumbricoides eggs

    PubMed Central

    Beyhan, Yunus E.; Yilmaz, Hasan; Hokelek, Murat

    2016-01-01

    Objectives: To investigate the effects of acetic acid on durable Ascaris lumbricoides (A. lumbricoides) eggs to determine the effective concentration of vinegar and the implementation period to render the consumption of raw vegetables more reliable. Methods: This experimental study was performed in May 2015 in the Parasitology Laboratory, Faculty of Medicine, Yuzuncu Yil University, Van, Turkey. The A. lumbricoides eggs were divided into 2 groups. Eggs in the study group were treated with 1, 3, 5, and 10% acetic acid concentrations, and eggs in the control group were treated with Eosin. The eggs’ viability was observed at the following points in time during the experiment: 0, 10, 15, 20, 30, 45, and 60 minutes. Results: The 1% acetic acid was determined insufficient on the viability of Ascaris eggs. At the 30th minute, 3% acetic acid demonstrated 95% effectiveness, and at 5% concentration, all eggs lost their viability. Treatment of acetic acid at the ratio of 4.8% in 30 minutes, or a ratio of 4.3% in 60 minutes is required for full success of tretment. Conclusion: Since Ascaris eggs have 3 layers and are very resistant, the acetic acid concentration, which can be effective on these eggs are thought to be effective also on many other parasitic agents. In order to attain an active protection, after washing the vegetables, direct treatment with a vinegar containing 5% acetic acid for 30 minutes is essential. PMID:26905351

  2. New device for high-throughput viability screening of flow biofilms.

    PubMed

    Benoit, Michael R; Conant, Carolyn G; Ionescu-Zanetti, Cristian; Schwartz, Michael; Matin, A

    2010-07-01

    Control of biofilms requires rapid methods to identify compounds effective against them and to isolate resistance-compromised mutants for identifying genes involved in enhanced biofilm resistance. While rapid screening methods for microtiter plate well ("static") biofilms are available, there are no methods for such screening of continuous flow biofilms ("flow biofilms"). Since the latter biofilms more closely approximate natural biofilms, development of a high-throughput (HTP) method for screening them is desirable. We describe here a new method using a device comprised of microfluidic channels and a distributed pneumatic pump (BioFlux) that provides fluid flow to 96 individual biofilms. This device allows fine control of continuous or intermittent fluid flow over a broad range of flow rates, and the use of a standard well plate format provides compatibility with plate readers. We show that use of green fluorescent protein (GFP)-expressing bacteria, staining with propidium iodide, and measurement of fluorescence with a plate reader permit rapid and accurate determination of biofilm viability. The biofilm viability measured with the plate reader agreed with that determined using plate counts, as well as with the results of fluorescence microscope image analysis. Using BioFlux and the plate reader, we were able to rapidly screen the effects of several antimicrobials on the viability of Pseudomonas aeruginosa PAO1 flow biofilms.

  3. The mouse dead-end gene isoform α is necessary for germ cell and embryonic viability

    PubMed Central

    Bhattacharya, Chitralekha; Aggarwal, Sita; Zhu, Rui; Kumar, Madhu; Zhao, Ming; Meistrich, Marvin L.; Matin, Angabin

    2007-01-01

    Inactivation of the dead-end (Dnd1) gene in the Ter mouse strain results in depletion of primordial germ cells (PGCs) so that mice become sterile. However, on the 129 mouse strain background, loss of Dnd1 also increases testicular germ cell tumor incidence in parallel to PGC depletion. We report that inactivation of Dnd1 also affects embryonic viability in the 129 strain. Mouse Dnd1 encodes two protein isoforms, DND1-isoform α (DND1- α) and DND1-isoform β (DND1-β). Using isoform specific antibodies, we determined DND1-α is expressed in embryos and embryonic gonads whereas DND1-β expression is restricted to germ cells of the adult testis. Our data implicates DND1-α isoform to be necessary for germ cell viability and therefore its loss in Ter mice results in PGC depletion, germ cell tumor development and partial embryonic lethality in the 129 strain. PMID:17291453

  4. Estimating Renewable Energy Economic Potential in the United States. Methodology and Initial Results

    SciTech Connect

    Brown, Austin; Beiter, Philipp; Heimiller, Donna; Davidson, Carolyn; Denholm, Paul; Melius, Jennifer; Lopez, Anthony; Hettinger, Dylan; Mulcahy, David; Porro, Gian

    2016-08-01

    This report describes a geospatial analysis method to estimate the economic potential of several renewable resources available for electricity generation in the United States. Economic potential, one measure of renewable generation potential, may be defined in several ways. For example, one definition might be expected revenues (based on local market prices) minus generation costs, considered over the expected lifetime of the generation asset. Another definition might be generation costs relative to a benchmark (e.g., a natural gas combined cycle plant) using assumptions of fuel prices, capital cost, and plant efficiency. Economic potential in this report is defined as the subset of the available resource technical potential where the cost required to generate the electricity (which determines the minimum revenue requirements for development of the resource) is below the revenue available in terms of displaced energy and displaced capacity. The assessment is conducted at a high geospatial resolution (more than 150,000 technology-specific sites in the continental United States) to capture the significant variation in local resource, costs, and revenue potential. This metric can be a useful screening factor for understanding the economic viability of renewable generation technologies at a specific location. In contrast to many common estimates of renewable energy potential, economic potential does not consider market dynamics, customer demand, or most policy drivers that may incent renewable energy generation.

  5. Negative effects of temperature and atmospheric depositions on the seed viability of common juniper (Juniperus communis)

    PubMed Central

    Gruwez, R.; De Frenne, P.; De Schrijver, A.; Leroux, O.; Vangansbeke, P.; Verheyen, K.

    2014-01-01

    Background and Aims Environmental change is increasingly impacting ecosystems worldwide. However, our knowledge about the interacting effects of various drivers of global change on sexual reproduction of plants, one of their key mechanisms to cope with change, is limited. This study examines populations of poorly regenerating and threatened common juniper (Juniperus communis) to determine the influence of four drivers of global change (rising temperatures, nitrogen deposition, potentially acidifying deposition and altering precipitation patterns) on two key developmental phases during sexual reproduction, gametogenesis and fertilization (seed phase two, SP2) and embryo development (seed phase three, SP3), and on the ripening time of seeds. Methods In 42 populations throughout the distribution range of common juniper in Europe, 11 943 seeds of two developmental phases were sampled. Seed viability was determined using seed dissection and related to accumulated temperature (expressed as growing degree-days), nitrogen and potentially acidifying deposition (nitrogen plus sulfur), and precipitation data. Key Results Precipitation had no influence on the viability of the seeds or on the ripening time. Increasing temperatures had a negative impact on the viability of SP2 and SP3 seeds and decreased the ripening time. Potentially acidifying depositions negatively influenced SP3 seed viability, while enhanced nitrogen deposition led to lower ripening times. Conclusions Higher temperatures and atmospheric deposition affected SP3 seeds more than SP2 seeds. However, this is possibly a delayed effect as juniper seeds develop practically independently, due to the absence of vascular communication with the parent plant from shortly after fertilization. It is proposed that the failure of natural regeneration in many European juniper populations might be attributed to climate warming as well as enhanced atmospheric deposition of nitrogen and sulfur. PMID:24284814

  6. Viability of Giardia cysts suspended in lake, river, and tap water.

    PubMed Central

    deRegnier, D P; Cole, L; Schupp, D G; Erlandsen, S L

    1989-01-01

    Numerous waterborne outbreaks of giardiasis have occurred since 1965, yet little or no information has been reported on the viability of Giardia cysts in different aquatic environments. We have studied the viability of Giardia muris cysts suspended in lake, river, and tap water, while also monitoring water temperature, dissolved oxygen, pH, and other water quality parameters. Fecal pellets containing G. muris cysts were placed in glass vials covered with filter paper and exposed to (i) lake water at 15 ft (ca. 4.6 m) and 30 ft (ca. 9.2 m), (ii) river water, (iii) tap water, and (iv) distilled water stored under laboratory conditions. At 3, 7, 14, 28, 56, and 84 days, two vials from each environment were removed, and cyst viability was determined by (i) fluorogenic dye exclusion, (ii) production of giardiasis in an animal, and (iii) cyst morphology by Nomarski microscopy. In the fall, the cysts suspended at 30 ft in lake water remained viable for up to 56 days whereas cysts stored at 15 ft were nonviable after day 28. The G. muris cysts exposed to river water remained viable up to 28 days as determined by the production of giardiasis in mice. G. muris cysts suspended in tap water showed no signs of viability after 14 days, while cysts serving as controls (exposed to refrigerated distilled water) remained viable for up to 56 days. In the winter, Giardia cysts suspended in either lake or river water were viable for 56 to 84 days whereas cysts exposed to tap water were nonviable by day 14.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2757381

  7. Short Peptides Enhance Single Cell Adhesion and Viability on Microarrays

    PubMed Central

    Veiseh, Mandana; Veiseh, Omid; Martin, Michael C.; Asphahani, Fareid; Zhang, Miqin

    2011-01-01

    Single cell patterning holds important implications for biology, biochemistry, biotechnology, medicine, and bioinformatics. The challenge for single cell patterning is to produce small islands hosting only single cells and retaining their viability for a prolonged period of time. This study demonstrated a surface engineering approach that uses a covalently-bound short peptide as a mediator to pattern cells with improved single cell adhesion and prolonged cellular viability on gold patterned SiO2 substrates. The underlying hypothesis is that cell adhesion is regulated by the type, availability and stability of effective cell adhesion peptides, and thus covalently bound short peptides would promote cell spreading and thus, single cell adhesion and viability. The effectiveness of this approach and the underlying mechanism for the increased probability of single cell adhesion and prolonged cell viability by short peptides were studied by comparing cellular behavior of human umbilical cord vein endothelial cells on three model surfaces whose gold electrodes were immobilized with fibronectin, physically adsorbed Arg-Glu-Asp-Val-Tyr, and covalently-bound Lys-Arg-Glu-Asp-Val-Tyr, respectively. The surface chemistry and binding properties were characterized by reflectance Fourier transform infrared spectroscopy. Both short peptides were superior to fibronectin in producing adhesion of only single cells, while the covalently bound peptide also reduced apoptosis and necrosis of adhered cells. Controlling cell spreading by peptide binding domains to regulate apoptosis and viability represents a fundamental mechanism in cell-materials interaction and provides an effective strategy in engineering arrays of single cells. PMID:17371055

  8. Hydrogen Supplementation of Preservation Solution Improves Viability of Osteochondral Grafts

    PubMed Central

    Yamada, Takuya; Onuma, Kenji; Kuzuno, Jun; Ujihira, Masanobu; Kurokawa, Ryosuke; Sakai, Rina; Takaso, Masashi

    2014-01-01

    Allogenic osteochondral tissue (OCT) is used for the treatment of large cartilage defects. Typically, OCTs collected during the disease-screening period are preserved at 4°C; however, the gradual reduction in cell viability during cold preservation adversely affects transplantation outcomes. Therefore, improved storage methods that maintain the cell viability of OCTs are needed to increase the availability of high-quality OCTs and improve treatment outcomes. Here, we evaluated whether long-term hydrogen delivery to preservation solution improved the viability of rat OCTs during cold preservation. Hydrogen-supplemented Dulbecco's Modified Eagles Medium (DMEM) and University of Wisconsin (UW) solution both significantly improved the cell viability of OCTs during preservation at 4°C for 21 days compared to nonsupplemented media. However, the long-term cold preservation of OCTs in DMEM containing hydrogen was associated with the most optimal maintenance of chondrocytes with respect to viability and morphology. Our findings demonstrate that OCTs preserved in DMEM supplemented with hydrogen are a promising material for the repair of large cartilage defects in the clinical setting. PMID:25506061

  9. Exploring the dark side of MTT viability assay of cells cultured onto electrospun PLGA-based composite nanofibrous scaffolding materials.

    PubMed

    Qi, Ruiling; Shen, Mingwu; Cao, Xueyan; Guo, Rui; Tian, Xuejiao; Yu, Jianyong; Shi, Xiangyang

    2011-07-21

    One major method used to evaluate the biocompatibility of porous tissue engineering scaffolding materials is MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The MTT cell viability assay is based on the absorbance of the dissolved MTT formazan crystals formed in living cells, which is proportional to the number of viable cells. Due to the strong dye sorption capability of porous scaffolding materials, we propose that the cell viability determined from the MTT assay is likely to give a false negative result. In this study, we aim to explore the effect of the adsorption of MTT formazan on the accuracy of the viability assay of cells cultured onto porous electrospun poly(lactic-co-glycolic acid) (PLGA) nanofibers, HNTs (halloysite nanotubes)/PLGA, and CNTs (multiwalled carbon nanotubes)/PLGA composite nanofibrous mats. The morphology of electrospun nanofibers and L929 mouse fibroblasts cultured onto the nanofibrous scaffolds were observed using scanning electron microscopy. The viability of cells proliferated for 3 days was evaluated through the MTT assay. In the meantime, the adsorption of MTT formazan onto the same electrospun nanofibers was evaluated and the standard concentration-absorbance curve was obtained in order to quantify the contribution of the adsorbed MTT formazan during the MTT cell viability assay. We show that the PLGA, and the HNTs- or CNTs-doped PLGA nanofibers display appreciable MTT formazan dye sorption, corresponding to 35.6-50.2% deviation from the real cell viability assay data. The better dye sorption capability of the nanofibers leads to further deviation from the real cell viability. Our study gives a general insight into accurate MTT cytotoxicity assessment of various porous tissue engineering scaffolding materials, and may be applicable to other colorimetric assays for analyzing the biological properties of porous scaffolding materials.

  10. What has happened to suicides during the Greek economic crisis? Findings from an ecological study of suicides and their determinants (2003–2012)

    PubMed Central

    Rachiotis, George; Stuckler, David; McKee, Martin; Hadjichristodoulou, Christos

    2015-01-01

    Objectives There is a controversy about the impact of economic crisis on suicide rates in Greece. We analysed recent suicide data to identify who has been most affected and the relationships to economic and labour market indicators. Setting Greece. Primary and secondary outcome measures Age-specific and sex-specific suicide rates in Greece for the period 2003–2012 were calculated using data provided by the Hellenic Statistical Authority. We performed a join-point analysis to identify discontinuities in suicide trends between 2003 and 2010, prior to austerity, and in 2011–2012, during the period of austerity. Regression models were used to assess relationships between unemployment, Gross Domestic Product (GDP) and suicide rates for the entire period by age and sex. Results The mean suicide rate overall rose by 35% between 2010 and 2012, from 3.37 to 4.56/100 000 population. The suicide mortality rate for men increased from 5.75 (2003–2010) to 7.43/100 000 (2011–2012; p<0.01). Among women, the suicide rate also rose, albeit less markedly, from 1.17 to 1.55 (p=0.03). When differentiated by age group, suicide mortality increased among both sexes in the age groups 20–59 and >60 years. We found that each additional percentage point of unemployment was associated with a 0.19/100 000 population rise in suicides (95% CI 0.11 to 0.26) among working age men. Conclusions We found a clear increase in suicides among persons of working age, coinciding with austerity measures. These findings corroborate concerns that increased suicide risk in Greece is a health hazard associated with austerity measures. PMID:25807950

  11. [Hydatid fertility and protoscolex viability in humans: study of 78 hydatid samples collected between 2005 and 2012 and analyzed at the parasitology laboratory of the Mustapha University Hospital Center of Algiers].

    PubMed

    Zait, H; Boulahbel, M; Zait, F; Achir, I; Guerchani, M T; Chaouche, H; Ladjadje, Y; Hamrioui, B

    2013-05-01

    An analysis at the Mustapha University Hospital Center of Algiers examined 78 hydatid samples collected between 2005 and 2012 to determine the fertility rate of metacestodes and the viability of protoscolices. The fertility rate of the hydatid cysts in humans was 88.4% and the protoscolex viability rate 74.5%. The fertility and viability rates found here are high, despite the use of scolicides.

  12. Important population viability analysis parameters for giant pandas (Aliuropoda melanoleuca).

    PubMed

    Gong, Minghao; Song, Yanling; Yang, Zhisong; Lin, Chen

    2012-06-01

    Population viability analysis (PVA) is a tool to evaluate the risk of extinction for endangered species and aid conservation decision-making. The quality of PVA output is dependent on parameters related to population dynamics and life-history; however, it has been difficult to collect this information for the giant panda (Aliuropoda melanoleuca), a rare and endangered mammal native to China, confined to some 30 fragmented habitat patches. Since giant pandas are long-lived, mature late, have lower reproductive rates, and show little sexual dimorphism, obtaining data to perform adequate PVA has been difficult. Here, we develop a parameter sensitivity index by modeling the dynamics of six giant panda populations in the Minshan Mountains, in order to determine the parameters most influential to giant panda populations. Our data shows that the giant panda populations are most sensitive to changes in four female parameters: initial breeding age, reproductive rate, mortality rate between age 0 and 1, and mortality rate of adults. The parameter sensitivity index strongly correlated with initial population size, as smaller populations were more sensitive to changes in these four variables. This model suggests that demographic parameters of females have more influence on the results of PVA, indicating that females may play a more important role in giant panda population dynamics than males. Consequently, reintroduction of female individuals to a small giant panda population should be a high priority for conservation efforts. Our findings form a technical basis for the coming program of giant panda reintroduction, and inform which parameters are crucial to successfully and feasibly monitoring wild giant panda populations.

  13. Metam sodium reduces viability and infectivity of Eimeria oocysts.

    PubMed

    Fetterer, R H; Jenkins, M C; Miska, K B; Cain, G D

    2010-06-01

    Metam sodium (MS, sodium N-methyldithiocarbamate) is a widely used soil pesticide. Fumigation or chemical sterilization of poultry litter containing infectious oocysts could be an effective strategy to block the transmission of avian coccidia. In the current study, the effect of MS on the viability and infectivity of ocysts was investigated. The development of isolated, unsporulated oocysts of both Eimeria tenella and Eimeria maxima was inhibited, in a dose-related manner (IC(50) 8 to 14 microg/ml), by exposure to aqueous MS. Most treated oocysts failed to develop beyond early stages of sporulation. To determine the effect of MS on infectivity, isolated oocysts of E. tenella , Eimeria acervulina , and E. maxima were exposed for 24 hr to aqueous concentrations of MS ranging from 0 to 1,000 microg/ml. Treated oocysts were inoculated into chickens, and parameters of coccidiosis infection were compared to chickens inoculated with equal numbers of untreated oocysts. In a dose-related manner, MS significantly reduced the infectivity of oocysts with maximum effect observed at a dose of 300 microg/ml. When a mixture of oocysts containing 3 coccidian species was exposed to 300 microg/ml MS, from 0 to 24 hr, infectivity of oocysts was significantly reduced after a minimum of 12 hr of exposure. Treatment of aqueous slurries of litter samples obtained from commercial poultry houses, with 300 microg/ml MS for 24 hr, prevented the sporulation of eimerian oocysts in the litter samples relative to untreated control samples. The results indicate that MS could be used to reduce coccidial contamination of poultry litter.

  14. Prospective evaluation of femoral head viability following femoral neck fracture

    SciTech Connect

    Binkert, B.; Kroop, S.A.; Nepola, I.V.; Grantham, A.S.; Alderson, P.O.

    1984-01-01

    The bone scans of 33 patients (pts) with recent subcapital fractures (fx) of the femur were evaluated prospectively to determine their value in predicting femoral head visability. Each of the 33 pts (ll men, 22 women, age range 30-92) had a pre-operative bone scan within 72 hrs of the fx (23 pts within 24 hrs). Anterior and posterior planar views of both hips and pinhole views (50% of pts) were obtained 2 hrs after administration of Tc-99m HDP. The femoral head was classified as perfused if it showed the same activity as the opposite normal side or if it showed only slightly decreased activity. Femoral heads showing absent activity were classified as nonperfused. Overall, 20 of the 33 pts showed a photopenic femoral head on the side of the fx. Only 2 pts showed increased activity at hte site of the fx. Internal fixation of the fx was performed in 23 pts, 12 of whom had one or more follow-up scans. Five of these 12 pts showed absent femoral head activity on their initial scan, but 2 showed later reperfusion. The other 7 pts showed good perfusion initially, with only 1 later showing decreased femoral head activity. The other 10 pts (7 of whom had absent femoral head activity) had immediate resection of the femoral head and insertion of a Cathcart prosthesis. The results suggest that femoral head activity seen on a bone scan in the immediate post-fx period is not always a reliable indicator of femoral head viability. Decreased femoral head activity may reflect, in part, compromised perfusion secondary to post-traumatic edema, with or without anatomic disruption of the blood supply.

  15. Regional population viability of grassland songbirds: Effects of agricultural management

    USGS Publications Warehouse

    Perlut, N.G.; Strong, A.M.; Donovan, T.M.; Buckley, N.J.

    2008-01-01

    Although population declines of grassland songbirds in North America and Europe are well-documented, the effect of local processes on regional population persistence is unclear. To assess population viability of grassland songbirds at a regional scale (???150,000 ha), we quantified Savannah Sparrow Passerculus sandwichensis and Bobolink Dolichonyx oryzivorus annual productivity, adult apparent survival, habitat selection, and density in the four most (regionally) common grassland treatments. We applied these data to a female-based, stochastic, pre-breeding population model to examine whether current grassland management practices can sustain viable populations of breeding songbirds. Additionally, we evaluated six conservation strategies to determine which would most effectively increase population trends. Given baseline conditions, over 10 years, simulations showed a slightly declining or stable Savannah Sparrow population (mean bootstrap ?? = 0.99; 95% CI = 1.00-0.989) and severely declining Bobolink population (mean bootstrap ?? = 0.75; 95% CI = 0.753-0.747). Savannah Sparrow populations were sensitive to increases in all demographic parameters, particularly adult survival. However for Bobolinks, increasing adult apparent survival, juvenile apparent survival, or preference by changing habitat selection cues for late-hayed fields (highest quality) only slightly decreased the rate of decline. For both species, increasing the amount of high-quality habitat (late- and middle-hayed) marginally slowed population declines; increasing the amount of low-quality habitat (early-hayed and grazed) marginally increased population declines. Both species were most sensitive to low productivity and survival on early-hayed fields, despite the fact that this habitat comprised only 18% of the landscape. Management plans for all agricultural regions should increase quality on both low- and high-quality fields by balancing habitat needs, nesting phenology, and species' response to

  16. Engineered cerium oxide nanoparticles: Effects on bacterial growth and viability

    SciTech Connect

    Pelletier, Dale A; Suresh, Anil K; Holton, Gregory A; McKeown, Catherine K; Wang, Wei; Gu, Baohua; Mortensen, Ninell P; Allison, David P; Joy, David Charles; Allison, Martin R; Brown, Steven D; Phelps, Tommy Joe; Doktycz, Mitchel John

    2010-01-01

    Interest in engineered nanostructures has risen in recent years due to their use in energy conservation strategies and biomedicine. To ensure prudent development and use of nanomaterials, the fate and effects of such engineered structures on the environment should be understood. Interactions of nanomaterials with environmental microorganisms are inevitable, but the general consequences of such interactions remain unclear. Further, standardized methods for assessing such interactions are lacking. Therefore, we have initiated a multianalytical approach to understand the interactions of synthesized nanoparticles with bacterial systems. These efforts are focused initially on cerium oxide nanoparticles and model bacteria in order to evaluate characterization procedures and the possible fate of such materials in the environment. In this study the effects of cerium oxide nanoparticles on the growth and viability of Gram-negative Escherichia coli and Shewanella oneidensis, a metal-reducing bacteria, and Gram-positive Bacillus subtilis were examined relative to particle size, growth media, pH, and dosage. A hydrothermal based synthesis procedure was used to prepare cerium oxide nanoparticles of defined sizes in order to eliminate complications originating from the use of organic solvents and surfactants. Bactericidal effects were determined by minimum inhibitory concentration, colony forming units, disc diffusion tests and Live/Dead assays. In growth inhibition experiments involving E. coli and B. subtilis, a clear strain and size-dependent inhibition was observed. S. oneidensis appeared to be unaffected by the cerium oxide nanoparticles. Transmission electron microscopy along with microarray-based transcriptional profiling have been used to understand the response mechanism of the bacteria. The use of multiple analytical approaches adds confidence to toxicity assessments while the use of different bacterial systems highlights the potential wide-ranging effects of

  17. Detection and viability of Lactococcus lactis throughout cheese ripening.

    PubMed

    Ruggirello, Marianna; Dolci, Paola; Cocolin, Luca

    2014-01-01

    Recent evidences highlighted the presence of Lactococcus lactis during late cheese ripening. For this reason, the role of this microorganism, well known as dairy starter, should be reconsidered throughout cheese manufacturing and ripening. Thus, the main objective of this study was to develop a RT-qPCR protocol for the detection, quantification and determination of the viability of L. lactis in ripened cheese samples by direct analysis of microbial nucleic acids. Standard curves were constructed for the specific quantification of L. lactis in cheese matrices and good results in terms of selectivity, correlation coefficient and efficiency were obtained. Thirty-three ripened cheeses were analyzed and, on the basis of RNA analysis, twelve samples showed 106 to 108 CFU of L. lactis per gram of product, thirteen from 103 to 105 CFU/g, and in eight cheeses, L. lactis was not detected. Traditional plating on M17 medium led to loads ranging from 105 to 109 CFU/g, including the cheese samples where no L. lactis was found by RT-qPCR. From these cheeses, none of the colonies isolated on M17 medium was identified as L. lactis species. These data could be interpreted as a lack of selectivity of M17 medium where colony growth is not always related to lactococcal species. At the same time, the absence or low abundance of L. lactis isolates on M17 medium from cheese where L. lactis was detected by RT-qPCR support the hypothesis that L. lactis starter populations are mainly present in viable but not culturable state during ripening and, for this reason, culture-dependent methods have to be supplemented with direct analysis of cheese.

  18. Impedance microflow cytometry for viability studies of microorganisms

    NASA Astrophysics Data System (ADS)

    Di Berardino, Marco; Hebeisen, Monika; Hessler, Thomas; Ziswiler, Adrian; Largiadèr, Stephanie; Schade, Grit

    2011-02-01

    Impedance-based Coulter counters and its derivatives are widely used cell analysis tools in many laboratories and use normally DC or low frequency AC to perform these electrical analyses. The emergence of micro-fabrication technologies in the last decade, however, provides a new means of measuring electrical properties of cells. Microfluidic approaches combined with impedance spectroscopy measurements in the radio frequency (RF) range increase sensitivity and information content and thus push single cell analyses beyond simple cell counting and sizing applications towards multiparametric cell characterization. Promising results have been shown already in the fields of cell differentiation and blood analysis. Here we emphasize the potential of this technology by presenting new data obtained from viability studies on microorganisms. Impedance measurements of several yeast and bacteria strains performed at frequencies around 10 MHz enable an easy discrimination between dead and viable cells. Moreover, cytotoxic effects of antibiotics and other reagents, as well as cell starvation can also be monitored easily. Control analyses performed with conventional flow cytometers using various fluorescent dyes (propidium iodide, oxonol) indicate a good correlation and further highlight the capability of this device. The label-free approach makes on the one hand the use of usually expensive fluorochromes obsolete, on the other hand practically eliminates laborious sample preparation procedures. Until now, online cell monitoring was limited to the determination of viable biomass, which provides rather poor information of a cell culture. Impedance microflow cytometry, besides other aspects, proposes a simple solution to these limitations and might become an important tool for bioprocess monitoring applications in the biotech industry.

  19. Viability and the moral status of the fetus.

    PubMed

    Campbell, A V

    1985-01-01

    The viability of the fetus has played a significant part in the framing of abortion legislation, but the use of viability as a criterion represents a compromise which is conceptually unclear and which fails to satisfy either side in the abortion debate. Both conservative and liberal views on abortion regard fetal development as morally irrelevant. For the moderate (or gradualist) view some point in the development must be found which indicates a change in the moral status of the fetus. Since viability changes according to available techniques for neonatal care it cannot be the criterion. Alternative criteria are surveyed and it is concluded that the onset of sensation is a significant transition point beyond which abortion and infanticide cannot be morally distinguished. It is suggested that either legislation should be amended to prohibit abortion after 18 to 20 weeks, or abortion to full term should be permitted and the possibility of legislation for infanticide be envisaged.

  20. [Selection on viability of individuals heterozygous for the temperature-sensitive lethal mutation l(2)M167(DTS) in experimental populations of Drosophila melanogaster].

    PubMed

    Kulikov, A M; Marec, F; Mitrofanov, V G

    2005-06-01

    In experiments on introduction of mutation l(2)M167(DTS) in Drosophila melanogaster populations, larval and pupal viability and developmental rate are limiting factors determining the intensity of selection on the l(2)M167(DTS) mutation. Notwithstanding the rapid elimination of the mutation from the population, positive selection for viability was shown, which increased fitness of the mutation carriers in generations. The fitness component viability was estimated in individuals l(2)M167(DTS)/+; relative to that of wild-type individuals, it varied from 0.1 to 1. Factors affecting this trait in overcrowded populations were found.

  1. Application of wide-field optical coherence tomography to monitoring of viability of rat brain in vivo

    NASA Astrophysics Data System (ADS)

    Sato, Manabu; Nishidate, Izumi

    2014-05-01

    We investigated the feasibility of OCT in monitoring the viability of the brain. It was confirmed that after an overdose of pentobarbital sodium salt for an euthanasia, the OCT signal intensity increased before cardiac arrest and finally became 2.7 times, and by periodically changing the tissue temperature from 20 to 32 °C in vivo, average correlation coefficients between the ratio of signal intensity (RSI) and temperature were determined to be -0:42 to -0:50. RSI reversibly changed with subsequent variations of temperatures and finally increased rapidly just before cardiac arrest. These results indicate that RSI could correspond to decreases in viability.

  2. Economic analysis

    SciTech Connect

    1980-06-01

    The Energy Policy and Conservation Act (EPCA) mandated that minimum energy efficiency standards be established for classes of refrigerators and refrigerator-freezers, freezers, clothes dryers, water heaters, room air conditioners, home heating equipment, kitchen ranges and ovens, central air conditioners, and furnaces. EPCA requires that standards be designed to achieve the maximum improvement in energy efficiency that is technologically feasible and economically justified. Following the introductory chapter, Chapter Two describes the methodology used in the economic analysis and its relationship to legislative criteria for consumer product efficiency assessment; details how the CPES Value Model systematically compared and evaluated the economic impacts of regulation on the consumer, manufacturer and Nation. Chapter Three briefly displays the results of the analysis and lists the proposed performance standards by product class. Chapter Four describes the reasons for developing a baseline forecast, characterizes the baseline scenario from which regulatory impacts were calculated and summarizes the primary models, data sources and assumptions used in the baseline formulations. Chapter Five summarizes the methodology used to calculate regulatory impacts; describes the impacts of energy performance standards relative to the baseline discussed in Chapter Four. Also discussed are regional standards and other program alternatives to performance standards. Chapter Six describes the procedure for balancing consumer, manufacturer, and national impacts to select standard levels. Details of models and data bases used in the analysis are included in Appendices A through K.

  3. The Economic Case for Education

    ERIC Educational Resources Information Center

    Woessmann, Ludger

    2016-01-01

    The case for education can be made from many perspectives. This paper makes the case for education based on economic outcomes. Surveying the most recent empirical evidence, it shows the crucial role of education for individual and societal prosperity. Education is a leading determinant of economic growth, employment, and earnings in modern…

  4. Rethinking the approach to viability monitoring in seed genebanks.

    PubMed

    Hay, Fiona R; Whitehouse, Katherine J

    2017-01-01

    Seed viability monitoring, usually through a germination test, is a key aspect of genebank management; a low viability result triggers the regeneration of an accession in order to ensure that the genetic diversity of the accession is conserved and available for distribution. However, regular viability monitoring of large collections is costly in terms of seeds, labour and other resources. Genebanks differ in how they conduct their viability monitoring and how they collect, manage and store the data that are generated. In this article, we propose alternatives to the current norm of conducting an initial germination test soon after arrival at the genebank and then testing after regular, set storage intervals, as recommended in the Food and Agriculture Organization's Genebank Standards for Plant Genetic Resources for Food and Agriculture. We use real data from the International Rice Genebank (held at the International Rice Research Institute) to illustrate some of the issues regarding the accuracy and reliability of germination test results, in particular when they are used to predict the longevity of a seed lot in storage and to set viability monitoring intervals. We suggest the use of seed storage experiments on samples of seeds to identify which seed lots from a particular crop season to test first. We also give advice on the use of sequential testing schemes potentially to reduce the number of seeds used for viability testing; the use of tolerance tables to identify unlikely results when samples are subdivided into replicates; and what data to include in a genebank management database to improve the management of seed collections.

  5. Rethinking the approach to viability monitoring in seed genebanks

    PubMed Central

    Whitehouse, Katherine J.

    2017-01-01

    Abstract Seed viability monitoring, usually through a germination test, is a key aspect of genebank management; a low viability result triggers the regeneration of an accession in order to ensure that the genetic diversity of the accession is conserved and available for distribution. However, regular viability monitoring of large collections is costly in terms of seeds, labour and other resources. Genebanks differ in how they conduct their viability monitoring and how they collect, manage and store the data that are generated. In this article, we propose alternatives to the current norm of conducting an initial germination test soon after arrival at the genebank and then testing after regular, set storage intervals, as recommended in the Food and Agriculture Organization's Genebank Standards for Plant Genetic Resources for Food and Agriculture. We use real data from the International Rice Genebank (held at the International Rice Research Institute) to illustrate some of the issues regarding the accuracy and reliability of germination test results, in particular when they are used to predict the longevity of a seed lot in storage and to set viability monitoring intervals. We suggest the use of seed storage experiments on samples of seeds to identify which seed lots from a particular crop season to test first. We also give advice on the use of sequential testing schemes potentially to reduce the number of seeds used for viability testing; the use of tolerance tables to identify unlikely results when samples are subdivided into replicates; and what data to include in a genebank management database to improve the management of seed collections. PMID:28361000

  6. [Viability of facultative anaerobic bacteria in commercial transport systems].

    PubMed

    Gruber, I M; Dmitrieva, M N; Gavrilova, N A; Zhigunova, O V; Nisilevich, V F

    2001-01-01

    The possibilities of the transport systems manufactured by Copan (Italy) and Deltalab (Spain) were studied on 15 microbial strains: representatives of the family Enterobacteriaceae (enterobacterial swabs with Cary-Blair medium) and the genus Streptococcus, as well as the species Neisseria meningitidis, Haemophilus influenzae (universal swabs with charcoal-enriched Amies medium). Microorganisms were shown to retain their viability (in colony-forming units, %) for 48 hours in the systems of both firms. H. influenzae exhibited greater viability in the system manufactured by Copan than in that manufactured by Deltalab (respectively, 62% and 28% in 24 hours, 19% and 6% in 48 hours).

  7. Population-specific life histories contribute to metapopulation viability

    USGS Publications Warehouse

    Halsey, Samniqueka J.; Bell, Timothy J.; McEachern, Kathryn; Pavlovic, Noel B.

    2016-01-01

    Restoration efforts can be improved by understanding how variations in life-history traits occur within populations of the same species living in different environments. This can be done by first understanding the demographic responses of natural occurring populations. Population viability analysis continues to be useful to species management and conservation with sensitivity analysis aiding in the understanding of population dynamics. In this study, using life-table response experiments and elasticity analyses, we investigated how population-specific life-history demographic responses contributed to the metapopulation viability of the Federally threatened Pitcher's thistle (Cirsium pitcheri). Specifically, we tested the following hypotheses: (1) Subpopulations occupying different environments within a metapopulation have independent demographic responses and (2) advancing succession results in a shift from a demographic response focused on growth and fecundity to one dominated by stasis. Our results showed that reintroductions had a positive contribution to the metapopulation growth rate as compared to native populations which had a negative contribution. We found no difference in succession on the contribution to metapopulation viability. In addition, we identified distinct population-specific contributions to metapopulation viability and were able to associate specific life-history demographic responses. For example, the positive impact of Miller High Dunes population on the metapopulation growth rate resulted from high growth contributions, whereas increased time of plant in stasis for the State Park Big Blowout population resulted in negative contributions. A greater understanding of how separate populations respond in their corresponding environment may ultimately lead to more effective management strategies aimed at reducing extinction risk. We propose the continued use of sensitivity analyses to evaluate population-specific demographic influences on

  8. Population viability analysis: using a modeling tool to assess the viability of tapir populations in fragmented landscapes.

    PubMed

    Medici, Emília Patrícia; Desbiez, Arnaud Leonard Jean

    2012-12-01

    A population viability analysis (PVA) was conducted of the lowland tapir populations in the Atlantic Forest of the Pontal do Paranapanema region, Brazil, including Morro do Diabo State Park (MDSP) and surrounding forest fragments. Results from the model projected that the population of 126 tapirs in MDSP is likely to persist over the next 100 years; however, 200 tapirs would be required to maintain a viable population. Sensitivity analysis showed that sub-adult mortality and adult mortality have the strongest influence on the dynamics of lowland tapir populations. High road-kill has a major impact on the MDSP tapir population and can lead to population extinction. Metapopulation modeling showed that dispersal of tapirs from MDSP to the surrounding fragments can be detrimental to the overall metapopulation, as fragments act as sinks. Nevertheless, the model showed that under certain conditions the maintenance of the metapopulation dynamics might be determinant for the persistence of tapirs in the region, particularly in the smaller fragments. The establishment of corridors connecting MDSP to the forest fragments models resulted in an increase in the stochastic growth rate, making tapirs more resilient to threats and catastrophes, but only if rates of mortality were not increased when using corridors. The PVA showed that the conservation of tapirs in the Pontal region depends on: the effective protection of MDSP; maintenance and, whenever possible, enhancement of the functional connectivity of the landscape, reducing mortality during dispersal and threats in the unprotected forest fragments; and neutralization of all threats affecting tapirs in the smaller forest fragments.

  9. Seeds of HOPE: a model for addressing social and economic determinants of health in a women's obesity prevention project in two rural communities.

    PubMed

    Benedict, Salli; Campbell, Marci; Doolen, Anne; Rivera, Imana; Negussie, Tezita; Turner-McGrievy, Gabrielle

    2007-10-01

    Socioeconomic status (SES) and income disparity are strong predictors of health, and health promotion interventions that address them are more likely to be meaningful to participants and to sustain positive effects. Seeds of HOPE is an innovative project that is the result of a long-standing collaboration between the University of North Carolina (UNC) Center for Health Promotion and Disease Prevention, a Centers for Disease Control and Prevention (CDC) Prevention Research Center, and communities in rural North Carolina. Initial formative work, including key informant interviews, community surveys, and focus groups, strengthened our understanding of the link between hope and health and the importance of addressing social and economic issues as part of our health promotion interventions. A Seeds of HOPE strategic plan was developed using a community-based participatory process and led to the idea to start Threads of HOPE, an enterprise that will serve as a business laboratory where women will produce and market a unique product and also learn business skills. Threads of HOPE will be a health-enhancing business and will serve as a training program for a new cadre of women entrepreneurs in two rural communities.

  10. Economic theory and international migration.

    PubMed

    Borjas, G J

    1989-01-01

    The modern literature on the economics of immigration focuses on 3 related issues: 1) what determines the size and skill composition of immigrants flows to any particular host country; 2) how do the immigrants adapt to the host country's economy; and 3) what is the impact of immigrants on the host country's economy? This article reviews the theoretical framework and empirical evidence provided by the economics literature on these questions. It demonstrates that the economic approach, using the assumption that migration behavior is guided by the search for better economic opportunities and that the exchanges among the various players are regulated by an immigration market, leads to substantial insights in to these issues.

  11. Contemporary health care economics: an overview.

    PubMed

    McLaughlin, Nancy; Ong, Michael K; Tabbush, Victor; Hagigi, Farhad; Martin, Neil A

    2014-11-01

    Economic evaluations provide a decision-making framework in which outcomes (benefits) and costs are assessed for various alternative options. Although the interest in complete and partial economic evaluations has increased over the past 2 decades, the quality of studies has been marginal due to methodological challenges or incomplete cost determination. This paper provides an overview of the main types of complete and partial economic evaluations, reviews key methodological elements to be considered for any economic evaluation, and reviews concepts of cost determination. The goal is to provide the clinician neurosurgeon with the knowledge and tools needed to appraise published economic evaluations and to direct high-quality health economic evaluations.

  12. Adhesion to and viability of Listeria monocytogenes on food contact surfaces.

    PubMed

    Silva, Sónia; Teixeira, Pilar; Oliveira, Rosario; Azeredo, Joana

    2008-07-01

    Listeria monocytogenes is an important pathogen responsible for major outbreaks associated with food products. Adhesion to surfaces leads to significant modifications in cell physiology. The aim of this work was to determine the adhesion ability of 10 isolates of L. monocytogenes to eight materials commonly used in kitchens and to evaluate the viability of the adhered cells. The materials assayed were stainless steel 304, marble, granite, glass, polypropylene from a bowl and from a cutting board, and two kinds of silestone. All L. monocytogenes strains attached to all surfaces, although to different extents. L. monocytogenes adhered most tightly to granite and marble, followed by stainless steel 304, glass, silestones, and finally polypropylene surfaces. Surfaces at the threshold between hydrophobicity and hydrophilicity, with high electron acceptor capability and a regular pattern of roughness, were more prone to attachment. Polypropylene surfaces displayed the highest percentage of viable bacteria (nearly 100%), whereas marble and granite had a lower percentage of cultivable cells, 69.5 and 78.7%, respectively. The lowest percentage of culturable bacteria was found on white silestone (18.5%). These results indicate that there are differences in adhered cell viability on different materials. Cell viability assays are important to better understand the cross-contamination process because only adhered bacteria that remain viable are responsible for postprocess contamination.

  13. Influence of oxidized low-density lipoproteins (LDL) on the viability of osteoblastic cells.

    PubMed

    Brodeur, Mathieu R; Brissette, Louise; Falstrault, Louise; Ouellet, Pascale; Moreau, Robert

    2008-02-15

    Cardiovascular diseases have recently been noted as potential risk factors for osteoporosis development. Although it is poorly understood how these two pathologies are related, it is a known fact that oxidized low-density lipoproteins (OxLDL) constitute potential determinants for both of them. The current study investigated the metabolism of OxLDL by osteoblasts and its effect on osteoblastic viability. The results obtained show that OxLDL are internalized but not degraded by osteoblasts while they can selectively transfer their CE to these cells. It is also demonstrated that OxLDL induce proliferation at low concentrations but cell death at high concentrations. This reduction of osteoblast viability was associated with lysosomal membrane damage caused by OxLDL as demonstrated by acridine orange relocalization. Accordingly, chloroquine, an inhibitor of lysosomal activity, accentuated cell death induced by OxLDL. Finally, we demonstrate that osteoblasts have the capacity to oxidize LDL and thereby potentially increase the local concentration of OxLDL. Overall, the current study confirms the potential role of OxLDL in the development of osteoporosis given its influence on osteoblastic viability.

  14. Non-invasive terahertz imaging of tissue water content for flap viability assessment

    PubMed Central

    Bajwa, Neha; Au, Joshua; Jarrahy, Reza; Sung, Shijun; Fishbein, Michael C.; Riopelle, David; Ennis, Daniel B.; Aghaloo, Tara; St. John, Maie A.; Grundfest, Warren S.; Taylor, Zachary D.

    2016-01-01

    Accurate and early prediction of tissue viability is the most significant determinant of tissue flap survival in reconstructive surgery. Perturbation in tissue water content (TWC) is a generic component of the tissue response to such surgeries, and, therefore, may be an important diagnostic target for assessing the extent of flap viability in vivo. We have previously shown that reflective terahertz (THz) imaging, a non-ionizing technique, can generate spatially resolved maps of TWC in superficial soft tissues, such as cornea and wounds, on the order of minutes. Herein, we report the first in vivo pilot study to investigate the utility of reflective THz TWC imaging for early assessment of skin flap viability. We obtained longitudinal visible and reflective THz imagery comparing 3 bipedicled flaps (i.e. survival model) and 3 fully excised flaps (i.e. failure model) in the dorsal skin of rats over a postoperative period of 7 days. While visual differences between both models manifested 48 hr after surgery, statistically significant (p < 0.05, independent t-test) local differences in TWC contrast were evident in THz flap image sets as early as 24 hr. Excised flaps, histologically confirmed as necrotic, demonstrated a significant, yet localized, reduction in TWC in the flap region compared to non-traumatized skin. In contrast, bipedicled flaps, histologically verified as viable, displayed mostly uniform, unperturbed TWC across the flap tissue. These results indicate the practical potential of THz TWC sensing to accurately predict flap failure 24 hours earlier than clinical examination. PMID:28101431

  15. Comparison of five incubation systems for rat liver slices using functional and viability parameters.

    PubMed

    Olinga, P; Groen, K; Hof, I H; De Kanter, R; Koster, H J; Leeman, W R; Rutten, A A; Van Twillert, K; Groothuis, G M

    1997-10-01

    Precision-cut liver slices are presently used for various research objects, e.g. to study metabolism, transport, and toxicity of xenobiotics. Various incubation systems are presently employed, but a systematic comparison between these incubation systems with respect to preservation of slice function has not been performed yet. Therefore, we started a comparative study to evaluate five of these systems: the shaken flask (an Erlenmeyer in a shaking water bath), the stirred-well (24-well culture plate equipped with grids and magnetic stirrers), rocker platform (6-well culture plate with Netwell insert rocked on a platform), the roller system (dynamic organ culture rolled on an insert in a glass vial), and the 6-well shaker (6-well culture plate in a shaking water bath). The liver slices were incubated in these incubation systems for 0.5, 1.5, and 24.5 h and subsequently subjected to viability and metabolic function tests. The viability of the incubated liver slices was evaluated by: potassium content, MTT assay, energy charge, histomorphology, and LDH leakage. Their metabolic functions were studied by determination of the metabolism of lidocaine, testosterone, and antipyrine. Up to 1.5 h of incubation all five incubation systems gave similar results with respect to viability and metabolic function of the liver slices. However, after 24 h, the shaken flask, the rocker platform, and the 6-well shaker incubation systems appeared to be superior to the stirred well and the roller incubation systems.

  16. Evaluation of an automated instrument for viability and concentration measurements of cryopreserved hematopoietic cells.

    PubMed

    Szabo, S E; Monroe, S L; Fiorino, S; Bitzan, J; Loper, K

    2004-01-01

    Two important parameters for determination of deleterious effects of cellular processing on hematopoietic progenitor cells are cell viability and concentration. The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins Hospital evaluated the Beckman Coulter Vi-Cell automated instrument for the measurement of these two parameters. Using 33 thawed hematopoietic progenitor cell samples, automated Vi-Cell viability results were compared to those obtained using the standard trypan blue manual method. In addition, cell concentrations from these samples were compared with results from the Model Z2 Coulter Counter. Chinese Hamster Ovary cells were used for the evaluation of Vi-Cell linearity at the Beckman Coulter Cellular Analysis Development Center. Significant correlation was obtained when the two methods were compared for both cell concentration and percentage viability (P < .0001). The results of the linearity study indicated that the Vi-Cell is linear from approximately 5 x 10(4) to greater than 1 x 10(7) cells/mL. The Vi-Cell uses sample volumes as low as 0.5 mL; cell diameters may be 2 to 70 microns. The Vi-Cell automated instrument offers many significant advantages for cell analyses in today's busy laboratory environment.

  17. Pollen Viability, Pistil Receptivity, and Embryo Development in Hybridization of Nelumbo nucifera Gaertn

    PubMed Central

    Wang, Yan-Li; Guan, Zhi-Yong; Chen, Fa-Di; Fang, Wei-Min; Teng, Nian-Jun

    2012-01-01

    Seed set is usually low and differs for different crosses of flower lotus (Nelumbo nucifera Gaertn.). The reasons remain unknown, and this has a negative impact on lotus breeding. To determine the causes, we carried out two crosses of flower lotus, that is, “Jinsenianhua” × “Qinhuaihuadeng” and “Qinhuaihuadeng” × “Jinsenianhua” and pollen viability, pistil receptivity, and embryo development were investigated. The pollen grains collected at 05:00-06:00 hrs had the highest viability, and the viabilities of “Jinsenianhua” and “Qinhuaihuadeng” were 20.6 and 15.7%, respectively. At 4 h after artificial pollination, the number of pollen grains germinating on each stigma reached a peak: 63.0 and 17.2 per stigma in “Jinsenianhua” × “Qinhuaihuadeng” and “Qinhuaihuadeng” × “Jinsenianhua”, respectively. At 1 d after artificial pollination, the percentages of normal embryos in the two crosses were 55.0 and 21.9%, respectively; however, at 11 d after pollination, the corresponding percentages were 20.8 and 11.2%. Seed sets of the two crosses were 17.9 and 8.0%, respectively. The results suggested that low pistil receptivity and embryo abortion caused low seed set in “Qinhuaihuadeng” × “Jinsenianhua”, whereas low fecundity of “Jinsenianhua” × “Qinhuaihuadeng” was mainly attributable to embryo abortion. PMID:22629182

  18. Protein and carbohydrate intake influence sperm number and fertility in male cockroaches, but not sperm viability

    PubMed Central

    Bunning, Harriet; Rapkin, James; Belcher, Laurence; Archer, C. Ruth; Jensen, Kim; Hunt, John

    2015-01-01

    It is commonly assumed that because males produce many, tiny sperm, they are cheap to produce. Recent work, however, suggests that sperm production is not cost-free. If sperm are costly to produce, sperm number and/or viability should be influenced by diet, and this has been documented in numerous species. Yet few studies have examined the exact nutrients responsible for mediating these effects. Here, we quantify the effects of protein (P) and carbohydrate (C) intake on sperm number and viability in the cockroach Nauphoeta cinerea, as well as the consequences for male fertility. We found the intake of P and C influenced sperm number, being maximized at a high intake of diets with a P : C ratio of 1 : 2, but not sperm viability. The nutritional landscapes for male fertility and sperm number were closely aligned, suggesting that sperm number is the major determinant of male fertility in N. cinerea. Under dietary choice, males regulate nutrient intake at a P : C ratio of 1 : 4.95, which is midway between the ratios needed to maximize sperm production and pre-copulatory attractiveness in this species. This raises the possibility that males regulate nutrient intake to balance the trade-off between pre- and post-copulatory traits in this species. PMID:25608881

  19. Satellite power system: Engineering and economic analysis summary

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A system engineering and economic analysis was conducted to establish typical reference baselines for the photovoltaic, solar thermal, and nuclear satellite power systems. Tentative conclusions indicate that feasibility and economic viability are characteristic of the Satellite Power System. Anticipated technology related to manufacturing, construction, and maintenance operations is described. Fuel consumption, environmental effects, and orbital transfer are investigated. Space shuttles, local space transportation, and the heavy lift launch vehicle required are also discussed.

  20. Feasibility of a novel approach for fast, economical determination of radiation damage in nuclear reactor cores. [Annual report, November 1, 1992--October 30, 1993

    SciTech Connect

    Was, G.S.

    1993-07-07

    Progress was made in the following areas: radioinduced segregation (modeling and experiment), deformation of irradiated microstructures, stress corrosion cracking of irradiated microstructures, and development of an apparatus to determine the role of deformation on the radiation microstructure in-situ. Materials used were based on Ni-Cr-Fe and 304L.

  1. Some economic tables for airships

    NASA Technical Reports Server (NTRS)

    Neumann, R. D.

    1975-01-01

    During the course of the Southern California Aviation Council study on lighter than air it was determined that some form of economic base must be developed for estimation of costs of the airship. The tables are presented.

  2. Preliminary technical and economic evaluation of vortex extraction devices

    SciTech Connect

    Kornreich, T. R.; Kottler, Jr., R. J.; Jennings, D. M.

    1980-04-01

    Two innovative vortex extraction devices - the Tornado Wind Energy System (TWES) and the Vortex Augmentor Concept (VAC) - are critically evaluated to provide a preliminary assessment of their technical and economic viability as compared to conventional horizontal axis wind energy systems. This assessment was carried out over a wide range of power output levels and augmentation ratios appropriate to each of the concepts.

  3. Economic implications of alternative potato cropping systems in Maine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustainable cropping systems and management practices are needed to improve agricultural viability and rural economic vitality in Maine and the surrounding region. Research is being conducted to 1) identify the constraints to potato system sustainability and 2) develop practices and management strat...

  4. Species-specific viability analysis of Pseudomonas aeruginosa, Burkholderia cepacia and Staphylococcus aureus in mixed culture by flow cytometry

    PubMed Central

    2014-01-01

    Background Bacterial species coexist commonly in mixed communities, for instance those occurring in microbial infections of humans. Interspecies effects contribute to alterations in composition of communities with respect to species and thus, to the course and severity of infection. Therefore, knowledge concerning growth and viability of single species in medically-relevant mixed communities is of high interest to resolve complexity of interspecies dynamics and to support development of treatment strategies. In this study, a flow cytometric method was established to assess the species-specific viability in defined three-species mixed cultures. The method enables the characterization of viability of Pseudomonas aeruginosa, Burkholderia cepacia and Staphylococcus aureus, which are relevant to lung infections of Cystic Fibrosis (CF) patients. The method combines fluorescence detection by antibody and lectin labeling with viability fluorescence staining using SYBR®Green I and propidium iodide. In addition, species-specific cell enumeration analysis using quantitative terminal restriction fragment length polymorphisms (qT-RFLP) was used to monitor the growth dynamics. Finally, to investigate the impact of substrate availability on growth and viability, concentrations of main substrates and metabolites released were determined. Results For each species, the time course of growth and viability during mixed culture cultivations was obtained by using qT-RFLP analysis in combination with flow cytometry. Comparison between mixed and pure cultures revealed for every species differences in growth properties, e.g. enhanced growth of P. aeruginosa in mixed culture. Differences were also observed for B. cepacia and S. aureus in the time course of viability, e.g. an early and drastic reduction of viability of S. aureus in mixed culture. Overall, P. aeruginosa clearly dominated the mixed culture with regard to obtained cell concentrations. Conclusions In combination with q

  5. Evaluating the Viability of Mobile Learning to Enhance Management Training

    ERIC Educational Resources Information Center

    Macdonald, Iain; Chiu, Jason

    2011-01-01

    A qualitative research project was conducted to test the viability of augmenting an e-learning program for workplace learners using mobile content delivered through smart phones. Ten learners taking a six week web-based e-learning course were given smart phones which enabled them to access approximately 70% of the course content, in addition to…

  6. 37 CFR 1.807 - Viability of deposit.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Viability of deposit. 1.807 Section 1.807 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES Biotechnology Invention Disclosures Deposit...

  7. 37 CFR 1.807 - Viability of deposit.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Viability of deposit. 1.807 Section 1.807 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES Biotechnology Invention Disclosures Deposit...

  8. 37 CFR 1.807 - Viability of deposit.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Viability of deposit. 1.807 Section 1.807 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES Biotechnology Invention Disclosures Deposit...

  9. 37 CFR 1.807 - Viability of deposit.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Viability of deposit. 1.807 Section 1.807 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES Biotechnology Invention Disclosures Deposit...

  10. 37 CFR 1.807 - Viability of deposit.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Viability of deposit. 1.807 Section 1.807 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES Biotechnology Invention Disclosures Deposit...

  11. Sewage sludge pasteurization by gamma radiation: Financial viability case studies

    NASA Astrophysics Data System (ADS)

    Swinwood, Jean F.; Kotler, Jiri

    This paper examines the financial viability of sewage sludge pasteurization by gamma radiation, by examining the following three North American scenarios: 1) Small volume sewage treatment plant experiencing high sludge disposal costs. 2) Large volume sewage treatment plant experiencing low sludge disposal costs. 3) Large volume sewage treatment plant experiencing high sludge disposal costs.

  12. Proving the Viability of a School Choice Voucher. Policy Brief

    ERIC Educational Resources Information Center

    Haller, Scott

    2015-01-01

    A recent Pioneer Institute report written by Ken Ardon and Cara Stilling Candal, "Modeling Urban Scholarship Vouchers in Massachusetts," explores the viability of a school choice voucher program in the Commonwealth. Nationally, school choice has been shown to improve parent satisfaction and student achievement, reduce racial segregation,…

  13. Influence of electroporation on chicken blastoderm cell viability in vitro.

    PubMed

    Wawrzynska, Magdalena; Bednarczyk, Marek; Łakota, Pawel; Lubiszewska, Marta

    2008-01-01

    The aim of this study was to compare two types of devices used for blastoderm cell (BC) transfection: the Nucleofector (Amaxa, Biosystems) and the Multiporator (Eppendorf). To assess the influence of electric current on BCs, different conditions of both nucleofection and electroporation were used. Next, the viability of cells was assessed. The highest number of cells (90.8%) was viable after nucleofection in the G10 program. After transfection in the presence of pmaxGFP, the A23 program was found to be most advantageous. The elecroporation experiment with the Multiporator (Eppendorf) showed a significant influence of osmotic pressure and voltage on BC viability. Namely, in the isoosmolar buffer BC viability was statistically higher (P < or = 0.05) in comparison to the hypoosmolar buffer. The, viability of cells was statistically higher (P < or = 0.05) after application of 25V as compared to 50V. The efficiency of transfection in the presence of EGFP-C 1 after electroporation in 2 pulses, 25V, 500 micros in the isoosmolar buffer was better than in the recommended conditions in the Amaxa Biosystems A23 program.

  14. Viability of stored seed: extension by cathodic protection.

    PubMed

    Pammenter, N W; Adamson, J H; Berjak, P

    1974-12-20

    Placing seeds on a negatively charged conductor extended their viability during artificial aging. Such cathodic protection may reduce free radical attack by providing a source of electrons. The results stupport the hypothesis of free radical damage to cellular components and are consistent with such damage being important in deteriorative senescence changes.

  15. Behavioral economics: Reunifying psychology and economics

    PubMed Central

    Camerer, Colin

    1999-01-01

    “Behavioral economics” improves the realism of the psychological assumptions underlying economic theory, promising to reunify psychology and economics in the process. Reunification should lead to better predictions about economic behavior and better policy prescriptions. PMID:10485865

  16. Economic assessment of biodiesel production from waste frying oils.

    PubMed

    Araujo, Victor Kraemer Wermelinger Sancho; Hamacher, Silvio; Scavarda, Luiz Felipe

    2010-06-01

    Waste frying oils (WFO) can be a good source for the production of biodiesel because this raw material is not part of the food chain, is low cost and can be used in a way that resolves environmental problems (i.e. WFO is no longer thrown into the sewage network). The goal of this article is to propose a method to evaluate the costs of biodiesel production from WFO to develop an economic assessment of this alternative. This method embraces a logistics perspective, as the cost of collection of oil from commercial producers and its delivery to biodiesel depots or plants can be relevant and is an issue that has been little explored in the academic literature. To determine the logistics cost, a mathematical programming model is proposed to solve the vehicle routing problem (VRP), which was applied in an important urban center in Brazil (Rio de Janeiro), a relevant and potential center for biodiesel production and consumption. Eighty-one biodiesel cost scenarios were compared with information on the commercialization of biodiesel in Brazil. The results obtained demonstrate the economic viability of biodiesel production from WFO in the urban center studied and the relevance of logistics in the total biodiesel production cost.

  17. Molecular Viability Testing of UV-Inactivated Bacteria.

    PubMed

    Weigel, Kris M; Nguyen, Felicia K; Kearney, Moira R; Meschke, John S; Cangelosi, Gerard A

    2017-03-10

    The polymerase chain reaction (PCR) is effective at detecting bacterial DNA in samples, but it is unable to differentiate viable bacteria from inactivated cells or free DNA fragments. New PCR-based analytical strategies have been developed to address this limitation. Molecular viability testing (MVT) correlates bacterial viability with the ability to rapidly synthesize species-specific ribosomal RNA precursor (pre-rRNA) in response to brief nutritional stimulation. Previous studies demonstrated that MVT can assess bacterial inactivation by chlorine, serum, and low-temperature pasteurization. Here, we demonstrate that MVT can detect inactivation of Escherichia coli, Aeromonas hydrophila, and Enterococcus faecalis cells by ultraviolet (UV) irradiation. Some UV-inactivated E. coli cells transiently retained the ability to synthesize pre-rRNA post-irradiation (generating false-positive MVT results), but this activity ceased within one hour following UV exposure. Viable but transiently undetectable (by culture) E. coli cells were consistently detected by MVT. An alternative viability testing method, viability PCR (vPCR), correlates viability with cell envelope integrity. This method did not distinguish viable from UV-inactivated bacteria under some conditions, indicating that the inactivated cells retained intact cell envelopes. MVT holds promise as a means to rapidly assess microbial inactivation by UV treatment.IMPORTANCE Ultraviolet (UV) irradiation is increasingly used to disinfect water, food, and other materials for human use. Confirming the effectiveness of UV disinfection remains a challenging task. In particular, microbiological methods that rely on rapid detection of microbial DNA can yield misleading results. This is due to the detection of "remnant" DNA associated with dead microbial cells. This report describes a novel method that rapidly distinguishes living from dead microbial cells after UV disinfection.

  18. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of C02 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales

    SciTech Connect

    Michael F. Morea

    1997-10-24

    The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO2 enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot CO2 project will demonstrate the economic viability and widespread applicability of CO2 flooding in fractured siliceous shale reservoirs of the San Joaquin Valley. The research consists of four primary work processes: Reservoir Matrix and Fluid Characterization; Fracture Characterization; Reservoir Modeling and Simulation; and CO2 Pilot Flood and Evaluation. Work done in these areas is subdivided into two phases or budget periods. The first phase of the project will focus on the application of a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work will be used to evaluate how the reservoir will respond to secondary recovery and EOR processes. The second phase of the project will include the implementation and evaluation of an advanced enhanced oil recovery (EOR) pilot in the United Anticline (West Dome) of the Buena Vista Hills Field.

  19. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of C02 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales

    SciTech Connect

    Michael F. Morea

    1997-04-25

    The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO2 enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot CO2 project will demonstrate the economic viability and widespread applicability of CO2 flooding in fractured siliceous shale reservoirs of the San Joaquin Valley. The research consists of four primary work processes: Reservoir Matrix and Fluid Characterization; Fracture Characterization; Reservoir Modeling and Simulation; and CO2 Pilot Flood and Evaluation. Work done in these areas is subdivided into two phases or budget periods. The first phase of the project will focus on the application of a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work will be used to evaluate how the reservoir will respond to secondary recovery and EOR processes. The second phase of the project will include the implementation and evaluation of an advanced enhanced oil recovery (EOR) pilot in the West Dome of the Buena Vista Hills Field.

  20. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of CO2 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales

    SciTech Connect

    Morea, Michael F.

    1999-11-01

    The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO2 enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot CO2 project will demonstrate the economic viability and widespread applicability of CO2 flooding in fractured siliceous shale reservoirs of the San Joaquin Valley. The research consists of four primary work processes: (1) Reservoir Matrix and Fluid Characterization; (2) Fracture characterization; (3) reservoir Modeling and Simulation; and (4) CO2 Pilot Flood and Evaluation. Work done in these areas is subdivided into two phases or budget periods. The first phase of the project will focus on the application of a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work will be used to evaluate how the reservoir will respond to secondary recovery and EOR processes. The second phase of the project will include the implementation and evaluation of an advanced enhanced oil recovery (EOR) pilot in the United Anticline (West Dome) of the Buena Vista Hills Field.

  1. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of CO2 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales

    SciTech Connect

    Morea, Michael F.

    1999-11-08

    The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO2 enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot CO2 project will demonstrate the economic viability and widespread applicability of CO2 flooding in fractured siliceous shale reservoirs of the San Joaquin Valley. The research consists of four primary work processes: (1) Reservoir Matrix and Fluid Characterization; (2) Fracture characterization; (3) reservoir Modeling and Simulation; and (4) CO2 Pilot Flood and Evaluation. Work done in these areas is subdivided into two phases or budget periods. The first phase of the project will focus on the application of a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work will be used to evaluate how the reservoir will respond to secondary recovery and EOR processes. The second phase of the project will include the implementation and evaluation of an advanced enhanced oil recovery (EOR) pilot in the United Anticline (West Dome) of the Buena Vista Hills Field.

  2. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of C02 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales

    SciTech Connect

    Michael F. Morea

    1998-04-23

    The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO2 enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot CO2 project will demonstrate the economic viability and widespread applicability of CO2 flooding in fractured siliceous shale reservoirs of the San Joaquin Valley. The research consists of four primary work processes: Reservoir Matrix and Fluid Characterization; Fracture Characterization; Reservoir Modeling and Simulation; and CO2 Pilot Flood and Evaluation. Work done in these areas is subdivided into two phases or budget periods. The first phase of the project will focus on the application of a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work will be used to evaluate how the reservoir will respond to secondary recovery and EOR processes. The second phase of the project will include the implementation and evaluation of an advanced enhanced oil recovery (EOR) pilot in the United Anticline (West Dome) of the Buena Vista Hills Field.

  3. Forest management and economics

    SciTech Connect

    Buongiorno, J.; Gilless, J.K.

    1987-01-01

    This volume provides a survey of quantitative methods, guiding the reader through formulation and analysis of models that address forest management problems. The authors use simple mathematics, graphics, and short computer programs to explain each method. Emphasizing applications, they discuss linear, integer, dynamic, and goal programming; simulation; network modeling; and econometrics, as these relate to problems of determining economic harvest schedules in even-aged and uneven-aged forests, the evaluation of forest policies, multiple-objective decision making, and more.

  4. Basic Economic Principles

    NASA Technical Reports Server (NTRS)

    Tideman, T. N.

    1972-01-01

    An economic approach to design efficient transportation systems involves maximizing an objective function that reflects both goals and costs. A demand curve can be derived by finding the quantities of a good that solve the maximization problem as one varies the price of that commodity, holding income and the prices of all other goods constant. A supply curve is derived by applying the idea of profit maximization of firms. The production function determines the relationship between input and output.

  5. Investigating the determinants of contractor's construction and demolition waste management behavior in Mainland China.

    PubMed

    Wu, Zezhou; Yu, Ann T W; Shen, Liyin

    2017-02-01

    The abundant generation of construction and demolition (C&D) waste presents a significant challenge to the sustainable development of the construction industry in Mainland China. As the implementer of construction activities, the contractor's C&D waste management performance plays an important role in C&D waste minimization. This paper aims to investigate the determinants of the contractor's C&D waste management behavior in Mainland China. The Theory of Planned Behavior (TPB) was selected as the basis of the theoretical model. In addition, three contextual constructs (i.e., economic viability, governmental supervision, and project constraints) were introduced, formulating the initial model. Based on the initial model, eight constructs were identified and seven hypotheses were proposed. A questionnaire survey was conducted to collect data and a Structural Equation Modeling (SEM) analysis was employed to test the proposed hypotheses. Results showed that the C&D waste management intention is not a significant determinant of contractor's C&D waste management behavior. The most important determinant is economic viability, followed by governmental supervision as the second most important determinant. Nevertheless, the construct of project constraints is an insignificant determinant for contractor's adoption of C&D waste management behavior. The research findings imply that, in Mainland China, the government, at this stage, plays an important role in guiding and promoting the contractor to exhibit better C&D waste management behavior.

  6. An economic assessment of STOL aircraft potential including terminal area environmental considerations. Volume 2: Appendices

    NASA Technical Reports Server (NTRS)

    Solomon, H. L.; Sokolsky, S.

    1973-01-01

    An economic assessment of short takeoff aircraft for short haul air transportation applications is presented. The economic viability and environmental compatibility of short takeoff aircraft service in high density areas were evaluated. The subjects discussed are: (1) aircraft configurations and performance, (2) airfield and terminal requirements, and (3) direct and indirect operating costs.

  7. Economic evaluation of a solar hot-water system--Palm Beach County, Florida

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Report projects solar-energy costs and savings for residential hot-water system over 20 year period. Evaluation uses technical and economic models with inputs based on working characteristics of installed system. Primary analysis permits calculation of economic viability for four other U.S. sites.

  8. Impact of release dynamics of laser-irradiated polymer micropallets on the viability of selected adherent cells

    PubMed Central

    Ma, Huan; Mismar, Wael; Wang, Yuli; Small, Donald W.; Ras, Mat; Allbritton, Nancy L.; Sims, Christopher E.; Venugopalan, Vasan

    2012-01-01

    We use time-resolved interferometry, fluorescence assays and computational fluid dynamics (CFD) simulations to examine the viability of confluent adherent cell monolayers to selection via laser microbeam release of photoresist polymer micropallets. We demonstrate the importance of laser microbeam pulse energy and focal volume position relative to the glass–pallet interface in governing the threshold energies for pallet release as well as the pallet release dynamics. Measurements using time-resolved interferometry show that increases in laser pulse energy result in increasing pallet release velocities that can approach 10 m s−1 through aqueous media. CFD simulations reveal that the pallet motion results in cellular exposure to transient hydrodynamic shear stress amplitudes that can exceed 100 kPa on microsecond timescales, and which produces reduced cell viability. Moreover, CFD simulation results show that the maximum shear stress on the pallet surface varies spatially, with the largest shear stresses occurring on the pallet periphery. Cell viability of confluent cell monolayers on the pallet surface confirms that the use of larger pulse energies results in increased rates of necrosis for those cells situated away from the pallet centre, while cells situated at the pallet centre remain viable. Nevertheless, experiments that examine the viability of these cell monolayers following pallet release show that proper choices for laser microbeam pulse energy and focal volume position lead to the routine achievement of cell viability in excess of 90 per cent. These laser microbeam parameters result in maximum pallet release velocities below 6 m s−1 and cellular exposure of transient hydrodynamic shear stresses below 20 kPa. Collectively, these results provide a mechanistic understanding that relates pallet release dynamics and associated transient shear stresses with subsequent cellular viability. This provides a quantitative, mechanistic basis for determining

  9. Dipeptide Piracetam Analogue Noopept Improves Viability of Hippocampal HT-22 Neurons in the Glutamate Toxicity Model.

    PubMed

    Antipova, T A; Nikolaev, S V; Ostrovskaya, P U; Gudasheva, T A; Seredenin, S B

    2016-05-01

    Effect of noopept (N-phenylacetyl-prolylglycine ethyl ester) on viability of neurons exposed to neurotoxic action of glutamic acid (5 mM) was studied in vitro in immortalized mouse hippocampal HT-22 neurons. Noopept added to the medium before or after glutamic acid improved neuronal survival in a concentration range of 10-11-10-5 M. Comparison of the effective noopept concentrations determined in previous studies on cultured cortical and cerebellar neurons showed that hippocampal neurons are more sensitive to the protective effect of noopept.

  10. Geothermal Project Database Supporting Barriers and Viability Analysis for Development by 2020 Timeline

    DOE Data Explorer

    Anna Wall

    2014-10-21

    This data provides the underlying project-level analysis and data sources complied in response to the DOE request to determine the amount of geothermal capacity that could be available to meet the President's request to double renewable energy capacity by 2020. The enclosed data contains compiled data on individual project names and locations (by geothermal area and region), ownership, estimated nameplate capacity, and project status, and also contains inferred data on the barriers and viability of the project to meet a 2020 development timeline. The analysis of this data is discussed in the attached NREL report.

  11. Viability and fertilizing capacity of cryopreserved sperm from three North American acipenseriform species: A retrospective study

    USGS Publications Warehouse

    Horvath, A.; Wayman, W.R.; Dean, J.C.; Urbanyi, B.; Tiersch, T.R.; Mims, S.D.; Johnson, D.; Jenkins, J.A.

    2008-01-01

    Populations of sturgeon across the globe are threatened due to unregulated harvest and habitat loss, and the status varies among species across North America. Ready access to viable and functional sperm would contribute to recovery programmes for these species. In this study, we examined the motility, viability (cell membrane integrity) of cryopreserved sperm from three North American acipenseriform species and fertilizing capacity. Milt samples were collected from captive shortnose sturgeon (Acipenser brevirostrum), wild paddlefish (Polyodon spathula) and pallid sturgeon (Scaphirhynchus albus) and cryopreserved using combinations of Modified Tsvetkova's (MT) extender, Original Tsvetkova's extender, and modified Hanks' balanced salt solution, along with the cryoprotectants methanol (MeOH) or dimethyl sulfoxide (DMSO). A dual-staining technique using the fluorescent stains SYBR-14 and propidium iodide was employed with flow cytometry to determine the percentages of spermatozoa that were viable by virtue of having intact membranes. The percentage of viable spermatozoa ranged from 5% to 12% in shortnose sturgeon, 30-59% in paddlefish, and 44-58% in pallid sturgeon. In the first experiment with shortnose sturgeon sperm, methanol allowed for higher values for dependent variables than did DMSO, and sperm viability generally correlated with post-thaw motility. However, fertilization rate, neurulation, or hatching rates were independent from these factors. In the second experiment with shortnose sturgeon, 5% MeOH combined with MT yielded higher values for all parameters tested than the other combinations: viability was correlated with motility, fertilization rate, and hatching rate. Overall, viability and post-thaw motility was not affected by the use of hyperosmotic extenders (OT) or cryoprotectants (DMSO), but their use decreased fertilization percentages. For paddlefish sperm (experiment 3), MT combined with 10% MeOH was clearly a good choice for cryopreservation

  12. Viability of fat cells over time after syringe suction lipectomy: the effects of cryopreservation.

    PubMed

    Son, Daegu; Oh, Jaehoon; Choi, Taehyun; Kim, Junhyung; Han, Kihwan; Ha, Seongyun; Lee, Kyungho

    2010-09-01

    The purpose of this study was to determine the late decline in viability of fat cells over time for fat tissue stored at -15 degrees C and -70 degrees C after harvest from abdominal liposuction. A total of 16 females were recruited for this study. The viability of fat cell specimens was measured after freezing for 1, 3, 7, 14, 28, and 56 days. A number of viable mature adipocytes were evaluated by fluorescence microscopy after staining with fluorescein diacetate and propidium iodide. The glycerol-3-phosphate dehydrogenase activity was measured in lipoaspirates before digestion and the XTT reduction assay was performed. In addition, the XTT reduction assay was also performed on isolated lipocytes and preadipocytes.The viability of mature adipocytes was very low for both the -15 degrees C and -70 degrees C samples after 1 day of freezing (13.3% +/- 7.4% and 12.6% +/- 6.3%, respectively). There was no statistically significant difference between the samples stored at the 2 temperatures. The GPDH activity of the lipoaspirates frozen, for 1 day, at -15 degrees C and -70 degrees C was 25.1% +/- 10% and 28.7% +/- 11%, respectively. For the XTT test, the fractional enzyme activity of the lipoaspirates frozen, for 1 day, at -15 degrees C and -70 degrees C was 30.0% +/- 10.9% and 36.1% +/- 12.3%, respectively. In addition, the adipocytes had low activity from day one: 15.4% +/- 7.2% at -15 degrees C and 11.5% +/- 5.6% at -70 degrees C. Furthermore, the preadipocytes had a low activity of 8.0% +/- 6.0% at -15 degrees C and 8.6% +/- 3.8% at -70 degrees C. At 8 weeks, there were few viable mature adipocytes and the activity of the cells was very low by XTT and GPDH testing.The results of this study showed that the viability of adipocytes declined rapidly after frozen storage for 1 day at both -15 degrees C and -70 degrees C, and decreased gradually in storage after 8 weeks; at which time only approximately 5% of the fat cells were alive. These findings suggest that the present

  13. Fungal Spores Viability on the International Space Station

    NASA Astrophysics Data System (ADS)

    Gomoiu, I.; Chatzitheodoridis, E.; Vadrucci, S.; Walther, I.; Cojoc, R.

    2016-11-01

    In this study we investigated the security of a spaceflight experiment from two points of view: spreading of dried fungal spores placed on the different wafers and their viability during short and long term missions on the International Space Station (ISS). Microscopic characteristics of spores from dried spores samples were investigated, as well as the morphology of the colonies obtained from spores that survived during mission. The selected fungal species were: Aspergillus niger, Cladosporium herbarum, Ulocladium chartarum, and Basipetospora halophila. They have been chosen mainly based on their involvement in the biodeterioration of different substrate in the ISS as well as their presence as possible contaminants of the ISS. From biological point of view, three of the selected species are black fungi, with high melanin content and therefore highly resistant to space radiation. The visual inspection and analysis of the images taken before and after the short and the long term experiments have shown that all biocontainers were returned to Earth without damages. Microscope images of the lids of the culture plates revealed that the spores of all species were actually not detached from the surface of the wafers and did not contaminate the lids. From the adhesion point of view all types of wafers can be used in space experiments, with a special comment on the viability in the particular case of iron wafers when used for spores that belong to B. halophila (halophilic strain). This is encouraging in performing experiments with fungi without risking contamination. The spore viability was lower in the experiment for long time to ISS conditions than that of the short experiment. From the observations, it is suggested that the environment of the enclosed biocontainer, as well as the species'specific behaviour have an important effect, reducing the viability in time. Even the spores were not detached from the surface of the wafers, it was observed that spores used in the

  14. Fungal Spores Viability on the International Space Station.

    PubMed

    Gomoiu, I; Chatzitheodoridis, E; Vadrucci, S; Walther, I; Cojoc, R

    2016-11-01

    In this study we investigated the security of a spaceflight experiment from two points of view: spreading of dried fungal spores placed on the different wafers and their viability during short and long term missions on the International Space Station (ISS). Microscopic characteristics of spores from dried spores samples were investigated, as well as the morphology of the colonies obtained from spores that survived during mission. The selected fungal species were: Aspergillus niger, Cladosporium herbarum, Ulocladium chartarum, and Basipetospora halophila. They have been chosen mainly based on their involvement in the biodeterioration of different substrate in the ISS as well as their presence as possible contaminants of the ISS. From biological point of view, three of the selected species are black fungi, with high melanin content and therefore highly resistant to space radiation. The visual inspection and analysis of the images taken before and after the short and the long term experiments have shown that all biocontainers were returned to Earth without damages. Microscope images of the lids of the culture plates revealed that the spores of all species were actually not detached from the surface of the wafers and did not contaminate the lids. From the adhesion point of view all types of wafers can be used in space experiments, with a special comment on the viability in the particular case of iron wafers when used for spores that belong to B. halophila (halophilic strain). This is encouraging in performing experiments with fungi without risking contamination. The spore viability was lower in the experiment for long time to ISS conditions than that of the short experiment. From the observations, it is suggested that the environment of the enclosed biocontainer, as well as the species'specific behaviour have an important effect, reducing the viability in time. Even the spores were not detached from the surface of the wafers, it was observed that spores used in the

  15. Fetal viability as a threshold to personhood. A legal analysis.

    PubMed

    Peterfy, A

    1995-12-01

    This essay opens with an examination of US laws concerning fetal viability as they apply to induced abortion, to a mother's right to refuse medical treatment necessary to save the life of a fetus, and to the rights to file suit for the wrongful death of unborn children. The history of abortion policies in the US is traced from the common law period of the early 19th century to the restrictive post-Civil War laws and the decisions of the Supreme Court in Roe vs. Wade, which upheld the constitutionality of previability abortions; Webster vs. Reproductive Health Services, in which the Court assigned viability to the 20th week of pregnancy and acknowledged that States could have a compelling previability interest in the fetus; and the Casey decision, which provided tolerance for limits on the availability of abortion before viability as long as the limits did not create an "undue burden" on the woman seeking the abortion. Courts dealing with the issue of compelling a mother to undergo medical treatment to save her fetus have been inconsistent as they balanced the state's interest in the fetus against the mother's rights to privacy. Judges have tended to err on the side of forcing the medical interventions, but the most recent trend is against this sort of judgement. In these cases, fetal viability has also served as a dividing line. The inconsistency of the legal system is illustrated by the fact that, whereas the fetus now has a legal existence, wrongful death actions entered on behalf of a nonviable fetus have often been denied although courts have been more willing to extend protection to fetuses in wrongful death tort cases than in abortion or medical intervention cases. Criminal law has a unique set of rules for dealing with fetuses as some states have broadened their definitions of "homicide" to include fetuses, even nonviable fetuses. Courts, however, are reluctant to enlarge criminal statutes on their own. While the central position given to the role of

  16. 5 CFR 841.405 - Economic assumptions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Economic assumptions. 841.405 Section 841... (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-GENERAL ADMINISTRATION Government Costs § 841.405 Economic assumptions. The determinations of the normal cost percentage will be based on the economic...

  17. 5 CFR 841.405 - Economic assumptions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Economic assumptions. 841.405 Section 841... (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-GENERAL ADMINISTRATION Government Costs § 841.405 Economic assumptions. The determinations of the normal cost percentage will be based on the economic...

  18. 5 CFR 841.405 - Economic assumptions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Economic assumptions. 841.405 Section 841... (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-GENERAL ADMINISTRATION Government Costs § 841.405 Economic assumptions. The determinations of the normal cost percentage will be based on the economic...

  19. 5 CFR 841.405 - Economic assumptions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Economic assumptions. 841.405 Section 841... (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-GENERAL ADMINISTRATION Government Costs § 841.405 Economic assumptions. The determinations of the normal cost percentage will be based on the economic...

  20. 5 CFR 841.405 - Economic assumptions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Economic assumptions. 841.405 Section 841... (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-GENERAL ADMINISTRATION Government Costs § 841.405 Economic assumptions. The determinations of the normal cost percentage will be based on the economic...

  1. Assessment of cell viability in primary neuronal cultures.

    PubMed

    Aras, Mandar A; Hartnett, Karen A; Aizenman, Elias

    2008-07-01

    This unit contains five protocols for assaying cell viability in vitro using primary neuronal cultures, including a novel method for use with transfected neurons. Three of the assays are based on the principle that cell death cascades alter membrane permeability. The lactate dehydrogenase (LDH) release assay measures the amount of the cytoplasmic enzyme released into the bathing medium, while the trypan blue and propidium iodide assays measure the ability of cells to exclude dye from their cytoplasm. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay measures the mitochondrial activity of viable cells by quantifying the conversion of the tetrazolium salt to its formazan product. Finally, the fifth assay details the measurement of luciferase expression as an indication of neuronal viability within a relatively small population of transfected neurons.

  2. False-Positive Viability PCR Results: An Association with Microtubes.

    PubMed

    Agustí, Gemma; Fittipaldi, Mariana; Codony, Francesc

    2017-03-01

    Currently, one of the most challenged points to expand the use of viability PCR technique is achieving the complete exclusion of dead cells amplification signals, thus avoiding the overestimation of live cells population. Considering that, and based on the hypothesis that DNA may be retained by microtube walls, the impact of the microtube was addressed on signals from live and heat-killed cells. A double-dye reagent, PEMAX™, which comprises a mix of photo-reactive azide forms of phenanthridium, was used in this work. We found that if both the incubation and the photoactivation steps are carried out in different microtubes, the dead cell signal is greatly reduced than when those steps are done in the same tube. Therefore, the strategy depicted in this study presents a simple and efficient step in minimizing false-positive signal when employing viability PCR.

  3. Assessment of canine neonatal viability-the Apgar score.

    PubMed

    Veronesi, M C

    2016-09-01

    Perinatal mortality is relatively high in dogs, with deaths peaking around the time of birth and during the first week of age. Among the several causes of canine perinatal mortality, whelping is the greatest cause. Therefore, early neonatal assistance at birth should be mandatory with dogs. In comparison with human neonatology, knowledge and technological ability in canine neonatology is tremendously scarce. The Apgar score for the newborn viability assessment at birth represents a feasible method for the prompt recognition of newborns that will need special assistance immediately after birth. The five parameters of the Apgar score were adapted to the canine species by different studies. Advantages and limits, as well as clinical applications, are presented and discussed in further detail. It was concluded that the Apgar score represents the easiest and simplest, non-invasive and reliable method, that could be performed under every clinical and practical condition, for newborn puppies viability evaluations and short-term survival prognosis.

  4. Hybrid Viability and Fertility in Co-occuring Plant Species

    NASA Astrophysics Data System (ADS)

    Hernandez, E.; Garcia, C.; Yost, J.

    2012-12-01

    Similar species of plants can co-exist due to reproductive barriers that keep them from hybridizing. In the case of Lasthenia gracilis and L. californica, certain reproductive barriers allow them to co-exist at Jasper Ridge without hybridization. The two species are locally adapted to different regions of the same hillside, and have slight differences in flowering time but hybrids can be created at low rate in the green house. We tested the viability and fertility of green house produced hybrids to quantify post-zygotic reproductive isolation at Jasper Ridge. We planted 10 hybrid seeds and 10 control seeds from 11 different families. We measured the percent germination, survival to flowering and pollen fertility of the seeds. We expect lower germination, lower survival to flowering, and lower pollen viability of hybrid seeds as compared to control seeds.

  5. Song Diversity Predicts the Viability of Fragmented Bird Populations

    PubMed Central

    Laiolo, Paola; Vögeli, Matthias; Serrano, David; Tella, José L.

    2008-01-01

    In the global scenario of increasing habitat fragmentation, finding appropriate indicators of population viability is a priority for conservation. We explored the potential of learned behaviours, specifically acoustic signals, to predict the persistence over time of fragmented bird populations. We found an association between male song diversity and the annual rate of population change, population productivity and population size, resulting in birds singing poor repertoires in populations more prone to extinction. This is the first demonstration that population viability can be predicted by a cultural trait (acquired via social learning). Our results emphasise that cultural attributes can reflect not only individual-level characteristics, but also the emergent population-level properties. This opens the way to the study of animal cultural diversity in the increasingly common human-altered landscapes. PMID:18350158

  6. Nuclear Power Options Viability Study. Volume 4. Bibliography

    SciTech Connect

    Trauger, D B; White, J D; Sims, J W

    1986-09-01

    Documents in the Nuclear Power Options Viability Study (NPOVS) bibliography are classified under one of four headings or categories as follows: nuclear options; light water reactors; liquid metal reactors; and high temperature reactors. The collection and selection of these documents, beginning early in 1984 and continuing through March of 1986, was carried out in support of the study's objective: to explore the viabilities of several nuclear electric power generation options for commercial deployment in the United States between 2000 and 2010. There are approximately 550 articles, papers, reports, and books in the bibliography that have been selected from some 2000 surveyed. The citations have been made computer accessible to facilitate rapid on-line retrieval by keyword, author, corporate author, title, journal name, or document number.

  7. Viability of vector-tensor theories of gravity

    SciTech Connect

    Jimenez, Jose Beltran; Maroto, Antonio L. E-mail: maroto@fis.ucm.es

    2009-02-15

    We present a detailed study of the viability of general vector-tensor theories of gravity in the presence of an arbitrary temporal background vector field. We find that there are six different classes of theories which are indistinguishable from General Relativity by means of local gravity experiments. We study the propagation speeds of scalar, vector and tensor perturbations and obtain the conditions for classical stability of those models. We compute the energy density of the different modes and find the conditions for the absence of ghosts in the quantum theory. We conclude that the only theories which can pass all the viability conditions for arbitrary values of the background vector field are not only those of the pure Maxwell type, but also Maxwell theories supplemented with a (Lorentz type) gauge fixing term.

  8. Assessing population viability while accounting for demographic and environmental uncertainty.

    PubMed

    Oppel, Steffen; Hilton, Geoff; Ratcliffe, Norman; Fenton, Calvin; Daley, James; Gray, Gerard; Vickery, Juliet; Gibbons, David

    2014-07-01

    Predicting the future trend and viability of populations is an essential task in ecology. Because many populations respond to changing environments, uncertainty surrounding environmental responses must be incorporated into population assessments. However, understanding the effects of environmental variation on population dynamics requires information on several important demographic parameters that are often difficult to estimate. Integrated population models facilitate the integration of time series data on population size and all existing demographic information from a species, allowing the estimation of demographic parameters for which limited or no empirical data exist. Although these models are ideal for assessments of population viability, they have so far not included environmental uncertainty. We incorporated environmental variation in an integrated population model to account for both demographic and environmental uncertainty in an assessment of population viability. In addition, we used this model to estimate true juvenile survival, an important demographic parameter for population dynamics that is difficult to estimate empirically. We applied this model to assess the past and future population trend of a rare island endemic songbird, the Montserrat Oriole Icterus oberi, which is threatened by volcanic activity. Montserrat Orioles experienced lower survival in years with volcanic ashfall, causing periodic population declines that were compensated by higher seasonal fecundity in years with high pre-breeding season rainfall. Due to the inclusion of both demographic and environmental uncertainty in the model, the estimated population growth rate in the immediate future was highly imprecise (95% credible interval 0.844-1.105), and the probability of extinction after three generations (in the year 2028) was low (2.1%). This projection demonstrates that accounting for both demographic and environmental sources of uncertainty provides a more realistic assessment

  9. Fermented red ginseng extract inhibits cancer cell proliferation and viability.

    PubMed

    Oh, Jisun; Jeon, Seong Bin; Lee, Yuri; Lee, Hyeji; Kim, Ju; Kwon, Bo Ra; Yu, Kang-Yeol; Cha, Jeong-Dan; Hwang, Seung-Mi; Choi, Kyung-Min; Jeong, Yong-Seob

    2015-04-01

    Red ginseng (Panax ginseng C.A. Meyer) is the most widely recognized medicinal herb due to its remedial effects in various disorders, such as cancers, diabetes, and heart problems. In this study, we investigated the anticancer effect of fermented red ginseng extract (f-RGE; provided by Jeonju Biomaterials Institute, Jeonju, South Korea) in a parallel comparison with the effect of nonfermented red ginseng extract (nf-RGE; control) on several cancer cell lines--MCF-7 breast cancer cells, HepG2 hepatocellular carcinoma cells, and reprogrammed MCF-7 cells (mimicking cancer stem cells). Cells were cultured at various concentrations of RGE (from 0.5 up to 5 mg/mL) and their viabilities and proliferative properties were examined. Our data demonstrate the following: (1) nf-RGE inhibited cell viability at ≥1 mg/mL for MCF-7 cells and ≥2 mg/mL for HepG2 cells, (2) in the presence of a carcinogenic agent, 12-O-tetradecanoylphorbol-13-acetate (TPA), nf-RGE treatment in combination with paclitaxel synergistically decreased MCF-7 as well as HepG2 cell viability, (3) f-RGE (which contained a greater level of Rg3 content) more effectively decreased the viability of MCF-7 and HepG2 cells compared to nf-RGE, and (4) f-RGE appeared more potent for inhibiting cancerous differentiation of reprogrammed MCF-7 cells in a synergistic fashion with paclitaxel, especially in the presence of TPA, compared to nf-RGE. These findings suggest that f-RGE treatment may be more effective for decreasing cancer cell survival by inducing apoptotic cell death and also presumably for preventing cancer stem cell differentiation compared to nf-RGE.

  10. Dormancy, activation and viability of Rhizopus oligosporus sporangiospores.

    PubMed

    Thanh, N V; Nout, M J R

    2004-04-15

    Interruption of dormancy to improve viability of Rhizopus oligosporus sporangiospores is crucial for the application of stored starter cultures for fungal (tempe) production. We aimed to assess the extent of dormancy and factors that could result in activation. Whereas heat treatments were unsuccessful, Malt Extract Broth (MEB) showed to be a good activation medium, with 80% of dormant spores being activated as measured by fluorescence microscopy using a fluorescent marker, compared with 11% with the control. Peptone and yeast extract but not glucose played an important role in activating dormant spores. Metabolically active (fluorescent) and swollen spores, followed by germ tubes were obtained after activation in MEB for 25 min., 2 and 4 h, respectively, at 37 degrees C. Simultaneously, some interesting transitions took place. Dormant spores represent 85-90% of the total spores at harvest and after drying. Their number decreased to 21-32% after activation with MEB with a concomitant increase of metabolically active spores. As a result of storage, some dormancy was lost, yielding an increase of active spores from 11.2% at harvest to 28.8% after 3 months storage. Levels of active spores were well correlated with their viability. By activation of dormant spores, their viability increased; levels of viable and active spores were maximum in 1 month old starter (61.7% and 75.9% of total spores, respectively) but gradually decreased with concomitant increase of the number of dead spores.

  11. Inhibiting ice recrystallization and optimization of cell viability after cryopreservation.

    PubMed

    Chaytor, Jennifer L; Tokarew, Jacqueline M; Wu, Luke K; Leclère, Mathieu; Tam, Roger Y; Capicciotti, Chantelle J; Guolla, Louise; von Moos, Elisabeth; Findlay, C Scott; Allan, David S; Ben, Robert N

    2012-01-01

    The ice recrystallization inhibition activity of various mono- and disaccharides has been correlated with their ability to cryopreserve human cell lines at various concentrations. Cell viabilities after cryopreservation were compared with control experiments where cells were cryopreserved with dimethylsulfoxide (DMSO). The most potent inhibitors of ice recrystallization were 220 mM solutions of disaccharides; however, the best cell viability was obtained when a 200 mM d-galactose solution was utilized. This solution was minimally cytotoxic at physiological temperature and effectively preserved cells during freeze-thaw. In fact, this carbohydrate was just as effective as a 5% DMSO solution. Further studies indicated that the cryoprotective benefit of d-galactose was a result of its internalization and its ability to mitigate osmotic stress, prevent intracellular ice formation and/or inhibit ice recrystallization. This study supports the hypothesis that the ability of a cryoprotectant to inhibit ice recrystallization is an important property to enhance cell viability post-freeze-thaw. This cryoprotective benefit is observed in three different human cell lines. Furthermore, we demonstrated that the ability of a potential cryoprotectant to inhibit ice recrystallation may be used as a predictor of its ability to preserve cells at subzero temperatures.

  12. Drying process strongly affects probiotics viability and functionalities.

    PubMed

    Iaconelli, Cyril; Lemetais, Guillaume; Kechaou, Noura; Chain, Florian; Bermúdez-Humarán, Luis G; Langella, Philippe; Gervais, Patrick; Beney, Laurent

    2015-11-20

    Probiotic formulations are widely used and are proposed to have a variety of beneficial effects, depending on the probiotic strains present in the product. The impact of drying processes on the viability of probiotics is well documented. However, the impact of these processes on probiotics functionality remains unclear. In this work, we investigated variations in seven different bacterial markers after various desiccation processes. Markers were composed of four different viability evaluation (combining two growth abilities and two cytometric measurements) and in three in vitro functionalities: stimulation of IL-10 and IL-12 production by PBMCs (immunomodulation) and bacterial adhesion to hexadecane. We measured the impact of three drying processes (air-drying, freeze-drying and spray-drying), without the use of protective agents, on three types of probiotic bacteria: Bifidobacterium bifidum, Lactobacillus plantarum and Lactobacillus zeae. Our results show that the bacteria respond differently to the three different drying processes, in terms of viability and functionality. Drying methods produce important variations in bacterial immunomodulation and hydrophobicity, which are correlated. We also show that adherence can be stimulated (air-drying) or inhibited (spray-drying) by drying processes. Results of a multivariate analysis show no direct correlation between bacterial survival and functionality, but do show a correlation between probiotic responses to desiccation-rewetting and the process used to dry the bacteria.

  13. Single cell viability and impact of heating by laser absorption.

    PubMed

    Wetzel, Franziska; Rönicke, Susanne; Müller, Karla; Gyger, Markus; Rose, Daniel; Zink, Mareike; Käs, Josef

    2011-09-01

    Optical traps such as tweezers and stretchers are widely used to probe the mechanical properties of cells. Beyond their large range of applications, the use of infrared laser light in optical traps causes significant heating effects in the cell. This study investigated the effect of laser-induced heating on cell viability. Common viability assays are not very sensitive to damages caused in short periods of time or are not practicable for single cell analysis. We used cell spreading, a vital ability of cells, as a new sensitive viability marker. The optical stretcher, a two beam laser trap, was used to simulate heat shocks that cells typically experience during measurements in optical traps. The results show that about 60% of the cells survived heat shocks without vital damage at temperatures of up to 58 ± 2°C for 0.5 s. By varying the duration of the heat shocks, it was shown that 60% of the cells stayed viable when exposed to 48 ± 2°C for 5 s.

  14. Nuclear cardiac imaging for the assessment of myocardial viability

    PubMed Central

    Slart, R.H.J.A.; Bax, J.J.; van der Wall, E.E.; van Veldhuisen, D.J.; Jager, P.L.; Dierckx, R.A.

    2005-01-01

    An important aspect of the diagnostic and prognostic work-up of patients with ischaemic cardiomyopathy is the assessment of myocardial viability. Patients with left ventricular dysfunction who have viable myocardium are the patients at highest risk because of the potential for ischaemia but at the same time benefit most from revascularisation. It is important to identify viable myocardium in these patients, and radionuclide myocardial scintigraphy is an excellent tool for this. Single-photon emission computed tomography perfusion scintigraphy (SPECT), whether using 201thallium, 99mTc-sestamibi, or 99mTc- tetrofosmin, in stress and/or rest protocols, has consistently been shown to be an effective modality for identifying myocardial viability and guiding appropriate management. Metabolic and perfusion imaging with positron emission tomography radiotracers frequently adds additional information and is a powerful tool for predicting which patients will have an improved outcome from revascularisation. New techniques in the nuclear cardiology field, such as attenuation corrected SPECT, dual isotope simultaneous acquisition (DISA) SPECT and gated FDG PET are promising and will further improve the detection of myocardial viability. Also the combination of multislice computed tomography scanners with PET opens possibilities of adding coronary calcium scoring and noninvasive coronary angiography to myocardial perfusion imaging and quantification. ImagesFigure 1Figure 2Figure 3 PMID:25696432

  15. Economic impact of stimulated technological activity. Part 1: Overall economic impact of technological progress: Its measurement

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Investigations were performed at the national economic level to explore the aggregate effects of technological progress on economic growth. Inadequacies in existing marco-economic yardsticks forced the study to focus on the cost savings effects achieved through technological progress. The central questions discussed in this report cover: (1) role of technological progress in economic growth, (2) factors determining the rate of economic growth due to technological progress; (3) quantitative measurements of relationships between technological progress, its determinants, and subsequent economic growth; and (4) effects of research and development activities of the space program. For Part 2, see N72-32174.

  16. Effect of bioink properties on printability and cell viability for 3D bioplotting of embryonic stem cells.

    PubMed

    Ouyang, Liliang; Yao, Rui; Zhao, Yu; Sun, Wei

    2016-09-16

    3D cell printing is an emerging technology for fabricating complex cell-laden constructs with precise and pre-designed geometry, structure and composition to overcome the limitations of 2D cell culture and conventional tissue engineering scaffold technology. This technology enables spatial manipulation of cells and biomaterials, also referred to as 'bioink', and thus allows study of cellular interactions in a 3D microenvironment and/or in the formation of functional tissues and organs. Recently, many efforts have been made to develop new bioinks and to apply more cell sources for better biocompatibility and biofunctionality. However, the influences of printing parameters on the shape fidelity of 3D constructs as well as on cell viability after the cell printing process have been poorly characterized. Furthermore, parameter optimization based on a specific cell type might not be suitable for other types of cells, especially cells with high sensibility. In this study, we systematically studied the influence of bioink properties and printing parameters on bioink printability and embryonic stem cell (ESC) viability in the process of extrusion-based cell printing, also known as bioplotting. A novel method was established to determine suitable conditions for bioplotting ESCs to achieve both good printability and high cell viability. The rheological properties of gelatin/alginate bioinks were evaluated to determine the gelation properties under different bioink compositions, printing temperatures and holding times. The bioink printability was characterized by a newly developed semi-quantitative method. The results demonstrated that bioinks with longer gelation times would result in poorer printability. The live/dead assay showed that ESC viability increased with higher printing temperatures and lower gelatin concentrations. Furthermore, an exponential relationship was obtained between ESC viability and induced shear stress. By defining the proper printability and

  17. Effects of hypothermic storage of striped bass (Morone saxatilis) sperm on intracellular calcium, reactive oxygen species formation, mitochondrial function, motility, and viability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted to determine the effect of hypothermic 24 h storage of striped bass sperm cells (Morone saxatilis) on viability, intracellular Ca2+ [Ca2+]i, mitochondrial membrane potential (''m), and reactive oxygen species (ROS) formation as determined by flow cytometry; motion activati...

  18. Effects of hypothermic storage of striped bass (Morone saxatilis) sperm on intracellular calcium, reactive oxygen species formation, mitochondrial function, motility, and viability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted to determine the effect of hypothermic 24 h storage of striped bass sperm cells on viability, intracellular Ca2+ ([Ca2+]i), mitochondrial membrane potential (D'm), and reactive oxygen species (ROS) formation (oxidation of hydroethidine to ethidium) as determined by flow cy...

  19. Withagulatin A inhibits hepatic stellate cell viability and procollagen I production through Akt and Smad signaling pathways

    PubMed Central

    Liu, Qiong; Chen, Jing; Wang, Xu; Yu, Liang; Hu, Li-hong; Shen, Xu

    2010-01-01

    Aim: To investigate the effects of the natural product Withagulatin A on hepatic stellate cell (HSC) viability and type I procollagen production. The potential mechanism underlying the pharmacological actions was also explored. Methods: The effect of Withagulatin A on cell viability was evaluated in HSC and LX-2 cells using a sulforhodamine B (SRB) assay. Cell cycle distribution was analyzed using flow cytometry. Type I procollagen gene expression was determined using real-time PCR. Regulation of signaling molecules by Withagulatin A was detected using Western blotting. Results: Primary rat HSCs and the human hepatic stellate cell line LX-2 treated with Withagulatin A (0.625-20 μmol/L) underwent a dose-dependent decrease in cell viability, which was associated with S phase arrest and the induction of cell apoptosis. In addition, the natural product decreased phosphorylation of the Akt/mTOR/p70S6K pathway that controls cell proliferation and survival. Furthermore, Withagulatin A (1, 2 μmol/L) inhibited transforming growth factor-β (TGF-β) stimulated type I procollagen gene expression, which was attributable to the suppression of TGF-β stimulated Smad2 and Smad3 phosphorylation. Conclusion: Our results demonstrated that Withagulatin A potently inhibited HSC viability and type I procollagen production, thereby implying that this natural product has potential use in the development of anti-fibrogenic reagents for the treatment of hepatic fibrosis. PMID:20644552

  20. Fibroblast Viability after Storage at 20 °C in Milk, Hank's Balanced Salt Solution and Coconut Water.

    PubMed

    Souza, Beatriz Dulcineia Mendes de; Alves, Ana Maria Hecke; Santos, Luciane Geanini Pena Dos; Simões, Claudia Maria de Oliveira; Felippe, Wilson Tadeu; Felippe, Mara Cristina Santos

    2016-01-01

    The objective of this study was to evaluate the effectiveness of various storage media at 20 °C in maintaining the viability of human periodontal ligament fibroblasts (HPLF) over time. HPLF were maintained at 20 °C in skim milk (SM), whole milk (WM), freshly prepared Hank's balanced salt solution (HBSS), Save-A-Tooth(r), natural coconut water (NCW), coconut water industrialized (ICW) and tap water (negative control) for 3, 6, 24, 48, 72, 96 and 120 h. Cells maintained in Minimal Essential Medium (MEM-37) at 37 °C served as a positive control. Cell viability was determined by MTT assay. Statistical analysis was performed by Kruskal-Wallis test and Scheffe test (α = 5%). From 24 h, NCW was significantly better in maintaining cell viability than all other tested storage media (p<0.05). SM and WM were significantly better than HBSS for up to 72 h. Save-A-Tooth(r) and ICW were the worst conservation storage media. In conclusion, the effectiveness of the tested storage media to maintain the viability of the periodontal ligament cells was as follows, in a descending order: NCW > MEM-37> SM and IM> HBSS> ICW > Save-A-Tooth(r)> tap water.

  1. Multiparametric flow cytometry allows rapid assessment and comparison of lactic acid bacteria viability after freezing and during frozen storage.

    PubMed

    Rault, Aline; Béal, Catherine; Ghorbal, Sarrah; Ogier, Jean-Claude; Bouix, Marielle

    2007-08-01

    Freezing is widely used for the long-term preservation of lactic acid bacteria, but often affects their viability and technological properties. Different methods are currently employed to determine bacterial cryotolerance, but they all require several hours or days before achieving results. The aim of this study was to establish the advantages of multiparametric flow cytometry by using two specific fluorescent probes to provide rapid assessment of the viability of four strains of Lactobacillus delbrueckii after freezing and during frozen storage. The relevance of carboxyfluorescein diacetate and propidium iodide to quantify bacterial viability was proven. When bacterial suspensions were simultaneously stained with these two fluorescent probes, three major subpopulations were identified: viable, dead and injured cells. The cryotolerance of four L. delbrueckii strains was evaluated by quantifying the relative percentages of each subpopulation before and after freezing, and throughout one month of storage at -80 degrees C. Results displayed significant differences in the resistance to freezing and frozen storage of the four strains when they were submitted to the same freezing and storage procedures. Whereas resistant strains displayed less than 10% of dead cells after one month of storage, one sensitive strain exhibited more than 50% of dead cells, together with 14% of stressed cells after freezing. Finally, this study proved that multiparametric flow cytometry was a convenient and rapid tool to evaluate the viability of lactic acid bacteria, and was well correlated with plate count results. Moreover, it made it possible to differentiate strains according to their susceptibility to freezing and frozen storage.

  2. Hydroxyethyl disulfide as an efficient metabolic assay for cell viability in vitro

    PubMed Central

    Li, Jie; Zhang, Donglan; Ward, Kathleen M.; Prendergast, George C.; Ayene, Iraimoudi S.

    2012-01-01

    Cell viability assays have a variety of well known practical and technical limitations. All the available approaches have disadvantages, such as non-linearity, high background and cumbersome protocols. Several commonly used tetrazolium chemicals rely upon generation of a colored formazan product formed by mitochondrial reduction of these compounds via phenazine methosulfate (PMS). However, sensitivity is inherently limited because their reduction relies on mitochondrial bioreduction and cellular transport of PMS, as well as accessibility to tetrazolium chemicals. In this study, we identify hydroxethyldisulfide (HEDS) as an inexpensive probe that can measure cellular metabolic activity without the need of PMS. In tissue culture medium, HEDS accurately quantitated metabolically active live cells in a linear manner superior to tetrazolium based and other assays. Cell toxicity produced by chemotherapeutics (cisplatin, etoposide), oxidants (hydrogen peroxide, acetaminophen), toxins (Phenyl arsine oxide, arsenite) or ionizing radiation was rapidly determined by the HEDS assay. We found that HEDS was superior to other commonly used assays for cell viability determinations in its solubility, membrane permeability, and intracellular conversion to a metabolic reporter that is readily transported into the extracellular medium. Our findings establish the use of HEDS in a simple, rapid and low cost assay to accurately quantify viable cells. PMID:22321380

  3. Hydroxyethyl disulfide as an efficient metabolic assay for cell viability in vitro.

    PubMed

    Li, Jie; Zhang, Donglan; Ward, Kathleen M; Prendergast, George C; Ayene, Iraimoudi S

    2012-06-01

    Cell viability assays have a variety of well known practical and technical limitations. All the available approaches have disadvantages, such as non-linearity, high background and cumbersome protocols. Several commonly used tetrazolium chemicals rely upon generation of a colored formazan product formed by mitochondrial reduction of these compounds via phenazine methosulfate (PMS). However, sensitivity is inherently limited because their reduction relies on mitochondrial bioreduction and cellular transport of PMS, as well as accessibility to tetrazolium chemicals. In this study, we identify hydroxethyldisulfide (HEDS) as an inexpensive probe that can measure cellular metabolic activity without the need of PMS. In tissue culture medium, HEDS accurately quantitated metabolically active live cells in a linear manner superior to tetrazolium based and other assays. Cell toxicity produced by chemotherapeutics (cisplatin, etoposide), oxidants (hydrogen peroxide, acetaminophen), toxins (phenyl arsine oxide, arsenite) or ionizing radiation was rapidly determined by the HEDS assay. We found that HEDS was superior to other commonly used assays for cell viability determinations in its solubility, membrane permeability, and intracellular conversion to a metabolic reporter that is readily transported into the extracellular medium. Our findings establish the use of HEDS in a simple, rapid and low cost assay to accurately quantify viable cells.

  4. Extinction-effective population index: incorporating life-history variations in population viability analysis.

    PubMed

    Fujiwara, Masami

    2007-09-01

    Viability status of populations is a commonly used measure for decision-making in the management of populations. One of the challenges faced by managers is the need to consistently allocate management effort among populations. This allocation should in part be based on comparison of extinction risks among populations. Unfortunately, common criteria that use minimum viable population size or count-based population viability analysis (PVA) often do not provide results that are comparable among populations, primarily because they lack consistency in determining population size measures and threshold levels of population size (e.g., minimum viable population size and quasi-extinction threshold). Here I introduce a new index called the "extinction-effective population index," which accounts for differential effects of demographic stochasticity among organisms with different life-history strategies and among individuals in different life stages. This index is expected to become a new way of determining minimum viable population size criteria and also complement the count-based PVA. The index accounts for the difference in life-history strategies of organisms, which are modeled using matrix population models. The extinction-effective population index, sensitivity, and elasticity are demonstrated in three species of Pacific salmonids. The interpretation of the index is also provided by comparing them with existing demographic indices. Finally, a measure of life-history-specific effect of demographic stochasticity is derived.

  5. The Effect of Tuning Cold Plasma Composition on Glioblastoma Cell Viability

    PubMed Central

    Cheng, Xiaoqian; Sherman, Jonathan; Murphy, William; Ratovitski, Edward; Canady, Jerome; Keidar, Michael

    2014-01-01

    Previous research in cold atmospheric plasma (CAP) and cancer cell interaction has repeatedly proven that the cold plasma induced cell death. It is postulated that the reactive oxygen species (ROS) and reactive nitrogen species (RNS) play a major role in the CAP cancer therapy. In this paper, we seek to determine a mechanism of CAP therapy on glioblastoma cells (U87) through an understanding of the composition of the plasma, including treatment time, voltage, flow-rate and plasma-gas composition. In order to determine the threshold of plasma treatment on U87, normal human astrocytes (E6/E7) were used as the comparison cell line. Our data showed that the 30 sec plasma treatment caused 3-fold cell death in the U87 cells compared to the E6/E7 cells. All the other compositions of cold plasma were performed based on this result: plasma treatment time was maintained at 30 s per well while other plasma characteristics such as voltage, flow rate of source gas, and composition of source gas were changed one at a time to vary the intensity of the reactive species composition in the plasma jet, which may finally have various effect on cells reflected by cell viability. We defined a term “plasma dosage” to summarize the relationship of all the characteristics and cell viability. PMID:24878760

  6. Population viability impacts of habitat additions and subtractions: A simulation experiment with endangered kangaroo rats

    EPA Science Inventory

    Species viability is influenced by the quality, quantity and configuration of habitat. For species at risk, a principal challenge is to identify landscape configurations that, if realized, would improve a population’s viability or restoration potential. Critical habitat patche...

  7. Effects of voluntary exercise on the viability, proliferation and BDNF levels of bone marrow stromal cells in rat pups born from morphine- dependent mothers during pregnancy.

    PubMed

    Haydari, Sakineh; Safari, Manouchehr; Zarbakhsh, Sam; Bandegi, Ahmad Reza; Miladi-Gorji, Hossein

    2016-11-10

    This study was designed to investigate whether free access to a running wheel during pregnancy in morphine-dependent mothers would influence the viability, proliferation and BDNF levels of bone marrow stromal cells in rat pups. Pregnant rats were made dependent by chronic administration of morphine in drinking water simultaneously with free access to a running wheel. Male pups are weaned at 21days of birth and their bones marrows were aspirated from the femurs and tibias and also the bone marrow stromal cells (BMSCs) cultured. MTT assay was used to determine cell viability and proliferation rate. The level of BDNF was measured in the supernant of BMSCs culture by ELISA. The sedentary morphine-dependent mothers' pups showed a significant increase in the percentage cell viability and proliferation rate and also a significant decrease in the BDNF protein levels in BMSCs. The rat pups borne from exercising the control and morphine-dependent mothers exhibited an increase in the percentage viability, proliferation rate and BDNF levels of the BMSCs. This study showed that maternal exercise during pregnancy in morphine-dependent and non-dependent mothers, with increasing of BDNF levels increased the proliferation and viability of BMSCs in the rat pups. Also, chronic administration of morphine during pregnancy was able to increase the proliferation and viability of BMSCs in the rat pups.

  8. Controlling laser-induced jet formation for bioprinting mesenchymal stem cells with high viability and high resolution.

    PubMed

    Ali, Muhammad; Pages, Emeline; Ducom, Alexandre; Fontaine, Aurelien; Guillemot, Fabien

    2014-09-12

    Laser-assisted bioprinting is a versatile, non-contact, nozzle-free printing technique which has demonstrated high potential for cell printing with high resolution. Improving cell viability requires determining printing conditions which minimize shear stress for cells within the jet and cell impact at droplet landing. In this context, this study deals with laser-induced jet dynamics to determine conditions from which jets arise with minimum kinetic energies. The transition from a sub-threshold regime to jetting regime has been associated with a geometrical parameter (vertex angle) which can be harnessed to print mesenchymal stem cells with high viability using slow jet conditions. Finally, hydrodynamic jet stability is also studied for higher laser pulse energies which give rise to supersonic but turbulent jets.

  9. A simplified economic filter for open-pit mining and heap-leach recovery of copper in the United States

    USGS Publications Warehouse

    Long, Keith R.; Singer, Donald A.

    2001-01-01

    Determining the economic viability of mineral deposits of various sizes and grades is a critical task in all phases of mineral supply, from land-use management to mine development. This study evaluates two simple tools for estimating the economic viability of porphyry copper deposits mined by open-pit, heap-leach methods when only limited information on these deposits is available. These two methods are useful for evaluating deposits that either (1) are undiscovered deposits predicted by a mineral resource assessment, or (2) have been discovered but for which little data has been collected or released. The first tool uses ordinary least-squared regression analysis of cost and operating data from selected deposits to estimate a predictive relationship between mining rate, itself estimated from deposit size, and capital and operating costs. The second method uses cost models developed by the U.S. Bureau of Mines (Camm, 1991) updated using appropriate cost indices. We find that the cost model method works best for estimating capital costs and the empirical model works best for estimating operating costs for mines to be developed in the United States.

  10. Supply Chain Viability for the North American Microwave Power Tube Industry

    DTIC Science & Technology

    2007-11-02

    Sponsored by DTIC Supply Chain Viability for the North American Microwave Power Tube Industry Supply Chain Viability for the US Microwave Power Tube...Industry iii Supply Chain Viability for the North American Microwave Power Tube Industry September 2002 Therese M. Philippi Federico M. Sciammarella...Patterson Air Force Base 45433-7739 Supply Chain Viability for the US Microwave Power Tube Industry ii REPORT DOCUMENTATION PAGE Form Approved Public

  11. Correlation of visual in vitro cytotoxicity ratings of biomaterials with quantitative in vitro cell viability measurements.

    PubMed

    Bhatia, Sujata K; Yetter, Ann B

    2008-08-01

    Medical devices and implanted biomaterials are often assessed for biological reactivity using visual scores of cell-material interactions. In such testing, biomaterials are assigned cytotoxicity ratings based on visual evidence of morphological cellular changes, including cell lysis, rounding, spreading, and proliferation. For example, ISO 10993 cytotoxicity testing of medical devices allows the use of a visual grading scale. The present study compared visual in vitro cytotoxicity ratings to quantitative in vitro cytotoxicity measurements for biomaterials to determine the level of correlation between visual scoring and a quantitative cell viability assay. Biomaterials representing a spectrum of biological reactivity levels were evaluated, including organo-tin polyvinylchloride (PVC; a known cytotoxic material), ultra-high molecular weight polyethylene (a known non-cytotoxic material), and implantable tissue adhesives. Each material was incubated in direct contact with mouse 3T3 fibroblast cell cultures for 24 h. Visual scores were assigned to the materials using a 5-point rating scale; the scorer was blinded to the material identities. Quantitative measurements of cell viability were performed using a 3-(4,5-dimethylthiozol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay; again, the assay operator was blinded to material identities. The investigation revealed a high degree of correlation between visual cytotoxicity ratings and quantitative cell viability measurements; a Pearson's correlation gave a correlation coefficient of 0.90 between the visual cytotoxicity score and the percent viable cells. An equation relating the visual cytotoxicity score and the percent viable cells was derived. The results of this study are significant for the design and interpretation of in vitro cytotoxicity studies of novel biomaterials.

  12. Bioluminescent, Nonlytic, Real-Time Cell Viability Assay and Use in Inhibitor Screening.

    PubMed

    Duellman, Sarah J; Zhou, Wenhui; Meisenheimer, Poncho; Vidugiris, Gediminas; Cali, James J; Gautam, Prson; Wennerberg, Krister; Vidugiriene, Jolanta

    2015-10-01

    Real-time continuous monitoring of cellular processes offers distinct advantages over traditional endpoint assays. A comprehensive representation of the changes occurring in live cells over the entire length of an experiment provides information about the biological status of the cell and informs decisions about the timing of treatments or the use of other functional endpoint assays. We describe a homogeneous, nonlytic, bioluminescent assay that measures cell viability in real time. This time-dependent measurement allowed us to monitor cell health for 72 h from the same test samples, distinguish differential cell growth, and investigate drug mechanism of action by analyzing time- and dose-dependent drug effects. The real-time measurements also allowed us to detect cell death immediately (>75% signal decrease within 15 min of digitonin addition), analyze drug potency versus efficacy, and identify cytostatic versus toxic drug effects. We screened an oncology compound library (Z' = 0.7) and identified compounds with varying activity at different time points (1.6% of the library showed activity within 3 h, whereas 35.4% showed a response by 47 h). The assay compared well with orthogonal endpoint cell viability assays and additionally provided data at multiple time points and the opportunity to multiplex assays on the same cells. To test the advantage of time-dependent measurements to direct optimal timing of downstream applications, we used the real-time cell viability assay to determine the ideal time to measure caspase activity by monitoring the onset of cell death and multiplexing a luminescent caspase activation assay on the same test samples.

  13. Bioluminescent, Nonlytic, Real-Time Cell Viability Assay and Use in Inhibitor Screening

    PubMed Central

    Zhou, Wenhui; Meisenheimer, Poncho; Vidugiris, Gediminas; Cali, James J.; Gautam, Prson; Wennerberg, Krister; Vidugiriene, Jolanta

    2015-01-01

    Abstract Real-time continuous monitoring of cellular processes offers distinct advantages over traditional endpoint assays. A comprehensive representation of the changes occurring in live cells over the entire length of an experiment provides information about the biological status of the cell and informs decisions about the timing of treatments or the use of other functional endpoint assays. We describe a homogeneous, nonlytic, bioluminescent assay that measures cell viability in real time. This time-dependent measurement allowed us to monitor cell health for 72 h from the same test samples, distinguish differential cell growth, and investigate drug mechanism of action by analyzing time- and dose-dependent drug effects. The real-time measurements also allowed us to detect cell death immediately (>75% signal decrease within 15 min of digitonin addition), analyze drug potency versus efficacy, and identify cytostatic versus toxic drug effects. We screened an oncology compound library (Z′ = 0.7) and identified compounds with varying activity at different time points (1.6% of the library showed activity within 3 h, whereas 35.4% showed a response by 47 h). The assay compared well with orthogonal endpoint cell viability assays and additionally provided data at multiple time points and the opportunity to multiplex assays on the same cells. To test the advantage of time-dependent measurements to direct optimal timing of downstream applications, we used the real-time cell viability assay to determine the ideal time to measure caspase activity by monitoring the onset of cell death and multiplexing a luminescent caspase activation assay on the same test samples. PMID:26383544

  14. Criteria for viability assessment of discarded human donor livers during ex vivo normothermic machine perfusion.

    PubMed

    Sutton, Michael E; op den Dries, Sanna; Karimian, Negin; Weeder, Pepijn D; de Boer, Marieke T; Wiersema-Buist, Janneke; Gouw, Annette S H; Leuvenink, Henri G D; Lisman, Ton; Porte, Robert J

    2014-01-01

    Although normothermic machine perfusion of donor livers may allow assessment of graft viability prior to transplantation, there are currently no data on what would be a good parameter of graft viability. To determine whether bile production is a suitable biomarker that can be used to discriminate viable from non-viable livers we have studied functional performance as well as biochemical and histological evidence of hepatobiliary injury during ex vivo normothermic machine perfusion of human donor livers. After a median duration of cold storage of 6.5 h, twelve extended criteria human donor livers that were declined for transplantation were ex vivo perfused for 6 h at 37 °C with an oxygenated solution based on red blood cells and plasma, using pressure controlled pulsatile perfusion of the hepatic artery and continuous portal perfusion. During perfusion, two patterns of bile flow were identified: (1) steadily increasing bile production, resulting in a cumulative output of ≥ 30 g after 6 h (high bile output group), and (2) a cumulative bile production <20 g in 6 h (low bile output group). Concentrations of transaminases and potassium in the perfusion fluid were significantly higher in the low bile output group, compared to the high bile output group. Biliary concentrations of bilirubin and bicarbonate were respectively 4 times and 2 times higher in the high bile output group. Livers in the low bile output group displayed more signs of hepatic necrosis and venous congestion, compared to the high bile output group. In conclusion, bile production could be an easily assessable biomarker of hepatic viability during ex vivo machine perfusion of human donor livers. It could potentially be used to identify extended criteria livers that are suitable for transplantation. These ex vivo findings need to be confirmed in a transplant experiment or a clinical trial.

  15. Demographics of polycystic kidney disease and captive population viability in pygmy hippopotamus (Choeropsis liberiensis).

    PubMed

    Flacke, Gabriella L; Tomkins, Joseph L; Black, Robert; Steck, Beatrice

    2017-02-15

    Polycystic kidney disease (PKD) was previously diagnosed at necropsy in several pygmy hippopotami (Choeropsis liberiensis) from the Smithsonian National Zoo and Zoo Basel, suggesting a threat to the long-term viability of the captive population. We determined the incidence and demographics of PKD in the captive population historically; we tested if the condition is linked to pedigree; we investigated mode of inheritance; we examined effects of PKD on longevity; we conducted survival analysis; and we examined long-term population viability. Thirty-seven percent of 149 necropsied adult pygmy hippos were affected by PKD, and it was more common in females, controlling for the overall female-biased sex-ratio. Prevalence increased significantly with age, but most hippos were beyond their reproductive prime before developing clinical signs; thus fecundity was likely unaffected. PKD was linked to pedigree and may exhibit X-linked dominance, but further research is needed to definitively establish the mode of inheritance. PKD did not affect longevity, overall or within any age class. There was no significant correlation between inbreeding coefficient (F) and PKD, and the prevalence in wild-caught and captive-born animals was similar. Longevity for both captive-born and inbred hippos (F > 0) was significantly shorter than longevity for their wild-caught and non-inbred counterparts. Demographic projections indicated the extant population will likely experience a slow increase over time, provided there are no space constraints. We conclude that although PKD is an important cause of morbidity and mortality in pygmy hippos, the condition is not a primary concern for overall viability of the captive population.

  16. Ketone supplementation decreases tumor cell viability and prolongs survival of mice with metastatic cancer.

    PubMed

    Poff, A M; Ari, C; Arnold, P; Seyfried, T N; D'Agostino, D P

    2014-10-01

    Cancer cells express an abnormal metabolism characterized by increased glucose consumption owing to genetic mutations and mitochondrial dysfunction. Previous studies indicate that unlike healthy tissues, cancer cells are unable to effectively use ketone bodies for energy. Furthermore, ketones inhibit the proliferation and viability of cultured tumor cells. As the Warburg effect is especially prominent in metastatic cells, we hypothesized that dietary ketone supplementation would inhibit metastatic cancer progression in vivo. Proliferation and viability were measured in the highly metastatic VM-M3 cells cultured in the presence and absence of β-hydroxybutyrate (βHB). Adult male inbred VM mice were implanted subcutaneously with firefly luciferase-tagged syngeneic VM-M3 cells. Mice were fed a standard diet supplemented with either 1,3-butanediol (BD) or a ketone ester (KE), which are metabolized to the ketone bodies βHB and acetoacetate. Tumor growth was monitored by in vivo bioluminescent imaging. Survival time, tumor growth rate, blood glucose, blood βHB and body weight were measured throughout the survival study. Ketone supplementation decreased proliferation and viability of the VM-M3 cells grown in vitro, even in the presence of high glucose. Dietary ketone supplementation with BD and KE prolonged survival in VM-M3 mice with systemic metastatic cancer by 51 and 69%, respectively (p < 0.05). Ketone administration elicited anticancer effects in vitro and in vivo independent of glucose levels or calorie restriction. The use of supplemental ketone precursors as a cancer treatment should be further investigated in animal models to determine potential for future clinical use.

  17. Ketone supplementation decreases tumor cell viability and prolongs survival of mice with metastatic cancer

    PubMed Central

    Poff, AM; Ari, C; Arnold, P; Seyfried, TN; D’Agostino, DP

    2014-01-01

    Cancer cells express an abnormal metabolism characterized by increased glucose consumption owing to genetic mutations and mitochondrial dysfunction. Previous studies indicate that unlike healthy tissues, cancer cells are unable to effectively use ketone bodies for energy. Furthermore, ketones inhibit the proliferation and viability of cultured tumor cells. As the Warburg effect is especially prominent in metastatic cells, we hypothesized that dietary ketone supplementation would inhibit metastatic cancer progression in vivo. Proliferation and viability were measured in the highly metastatic VM-M3 cells cultured in the presence and absence of β-hydroxybutyrate (βHB). Adult male inbred VM mice were implanted subcutaneously with firefly luciferase-tagged syngeneic VM-M3 cells. Mice were fed a standard diet supplemented with either 1,3-butanediol (BD) or a ketone ester (KE), which are metabolized to the ketone bodies βHB and acetoacetate. Tumor growth was monitored by in vivo bioluminescent imaging. Survival time, tumor growth rate, blood glucose, blood βHB and body weight were measured throughout the survival study. Ketone supplementation decreased proliferation and viability of the VM-M3 cells grown in vitro, even in the presence of high glucose. Dietary ketone supplementation with BD and KE prolonged survival in VM-M3 mice with systemic metastatic cancer by 51 and 69%, respectively (p < 0.05). Ketone administration elicited anticancer effects in vitro and in vivo independent of glucose levels or calorie restriction. The use of supplemental ketone precursors as a cancer treatment should be further investigated in animal models to determine potential for future clinical use. PMID:24615175

  18. Pollen viability and storage temperature for Southern highbush and Rabbiteye blueberry breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pollen viability, as measured by tetrad germination, has been reported, but these studies focused on freshly collected pollen and did not address viability of pollen stored at different temperatures over time. Moreover, genetic differences in pollen viability have been reported in blueberry genotype...

  19. Monitoring viability of seeds in gene banks: developing software tools to increase efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Monitoring the decline of seed viability is essential for effective long term seed storage in ex situ collections. Recent FAO Genebank Standards recommend monitoring intervals at one-third the time predicted for viability to fall to 85% of initial viability. This poster outlines the development of ...

  20. Production of fortified food for a public supplementary nutrition program: performance and viability of a decentralised production model for the Integrated Child Development Services Program, India.

    PubMed

    Antier, Clémentine; Kumar, Salil; Bhagwat, Sadhana; Sankar, Rajan

    2014-01-01

    Integrated Child Development Services in India through its supplementary nutrition programme covers over 100 million children, pregnant and lactating women across the country. Providing a hot cooked meal each day to children aged between 3-6 years and a take-home ration to children aged between 6-36 months, pregnant and lactating women, the Integrated Child Development Services faces a monumental task to deliver this component of services of desired quality and regularity at scale. From intermediaries or contractors who acted as agents for procuring and distributing food to procurement directly from large food manufacturers to using women groups as food producers, different State Governments have adopted a variety of strategies to procure and distribute food, especially the take-home ration. India's Supreme Court, through its directive of 2004, encouraged the Government to engage women's groups for the production of the supplementary food. This study was conducted to determine the operational performance, economic sustainability and social impact of a decentralised production model for India's Supplementary Nutrition Program, in which women groups run smallscale industrialised units. Data were collected through observation, interviews and group discussions with key stakeholders. Operational performance was analysed through standard performance indicators that measured consistency in production, compliance with quality standards and distribution regularity. Assessment of the economic viability included cost structure analysis, five-year projections, and financial ratios. Social impact was assessed using a qualitative approach. The pilot unit has demonstrated its operational performance and cost-efficiency. More data is needed to evaluate the scalability and sustainability of this decentralised model.

  1. Economic benefits of supersonic overland operation

    NASA Technical Reports Server (NTRS)

    Metwally, Munir

    1992-01-01

    Environmental concerns are likely to impose some restrictions on the next generation of supersonic commercial transport. There is a global concern over the effects of engine emissions on the ozone layer which protects life on Earth from ultraviolet radiation. There is also some concern over community noise. The High Speed Civil Transport (HSCT) must meet at least the current subsonic noise certification standards to be compatible with the future subsonic fleet. Concerns over sonic boom represent another environmental and marketing challenge to the HSCT program. The most attractive feature of the supersonic transport is speed, which offers the traveling public significant time-savings on long range routes. The sonic boom issue represents a major environmental and economic challenge as well. Supersonic operation overland produces the most desirable economic results. However, unacceptable overland sonic boom raise levels may force HSCT to use subsonic speeds overland. These environmental and economic challenges are likely to impose some restrictions on supersonic operation, thus introducing major changes to existing route structures and future supersonic network composition. The current subsonic route structure may have to be altered for supersonic transports to avoid sensitive areas in the stratosphere or to minimize overland flight tracks. It is important to examine the alternative route structure and the impact of these restrictions on the economic viability of the overall supersonic operation. Future market potential for HSCT fleets must be large enough to enable engine and airframe manufacturers to build the plane at a cost that provides them with an attractive return on investment and to sell it at a price that allows the airlines to operate with a reasonable margin of profit. Subsonic overland operation of a supersonic aircraft hinders its economic viability. Ways to increase the market potential of supersonic operation are described.

  2. Influence of electric current on bacterial viability in wastewater treatment.

    PubMed

    Wei, V; Elektorowicz, M; Oleszkiewicz, J A

    2011-10-15

    Minimizing the influence of electric current on bacterial viability in the electro-technologies such as electrophoresis and electrocoagulation is crucial in designing and operating the electric hybrid wastewater treatment system. In this study the biomass from a membrane bioreactor (MBR) was subjected to constant direct current and the bacterial viability was monitored against electrical intensity, duration as well as the spatial vicinity related to the electrodes. It was found that the bacterial viability was not significantly affected (less than 10% of death percentage) when the applied electric current density (CD) was less than 6.2 A/m2 after 4 h. The percentage of live cell dropped by 15% and 29% at CD of 12.3 A/m2 and 24.7 A/m2, respectively. The pH of electrolytic biomass fluid has shifted to alkaline (from nearly neutral to around pH 10) at CD above 12.3 A/m2, which could have been the contributing factor for the bacterial inactivation. The temperature change in the electrolytic media at all current densities during 4 h of experiment was less than 2 °C, thus temperature effects were negligible. Bacteria experienced different micro-environments in the electrochemical reactor. Bacterial cells on the cathode surface exhibited highest death rate, whereas bacteria outside the space between electrodes were the least affected. It was concluded that in an electro-technology integrated wastewater treatment process, sufficient mixing should be used to avoid localized inactivation of bacterial cells.

  3. Air quality biomonitoring through pollen viability of Fabaceae.

    PubMed

    Duro, Anna; Piccione, Vincenzo; Zampino, Daniela

    2013-05-01

    In this study, pollen viability and germination of three plant species, Cercis siliquastrum L., Robinia pseudoacacia L., and Spartium junceum L., belonging to the Fabaceae family, was evaluated in sites with different intensity of road traffic, constantly monitored with continuous analysers for air pollutants (carbon monoxide (CO), sulphur dioxide (SO(2)), and nitrogen dioxide (NO(2))) by the Municipality of Catania. Two sites, in which road traffic was absent, were selected, too. The percentages of viable pollen by 2,3,5-trypheniltetrazolium chloride (TTC) test ranged from 59.0 to 90.2 % in C. siliquastrum, from 61.5 to 83.5 % in S. junceum and from 67.5 to 84.3 % in R. pseudoacacia. The percentages of germination varied from 41.0 to 72.7 % in C. siliquastrum, from 42.0 to 64.7 % in S. junceum and from 38.3 to 66.3 % in R. pseudoacacia. The highest percentages of viable pollens were found in no-road traffic stations by either TTC or germination tests, while the lowest values were detected in a site characterised by heavy road traffic. In the monitored period (2007-2009), pollen viability, germinability and tube length of C. siliquastrum resulted in a significant negative correlation to CO, SO(2) and NO(2), whereas data from TTC and germination tests on S. junceum and R. pseudoacacia pollens were not well correlated to air pollutants. The results showed that pollen viability, germination and tube growth in C. siliquastrum were affected by air pollution. S. junceum and R. pseudoacacia were not very influenced by air pollutants, suggesting a different pollen sensitivity of these species.

  4. Projecting the success of plant restoration with population viability analysis

    USGS Publications Warehouse

    Bell, T.J.; Bowles, M.L.; McEachern, A.K.; Brigham, C.A.; Schwartz, M.W.

    2003-01-01

    Conserving viable populations of plant species requires that they have high probabilities of long-term persistence within natural habitats, such as a chance of extinction in 100 years of less than 5% (Menges 1991, 1998; Brown 1994; Pavlik 1994; Chap. 1, this Vol.). For endangered and threatened species that have been severely reduces in range and whose habitats have been fragmented, important species conservation strategies may include augmenting existing populations or restoring new viable populations (Bowles and Whelan 1994; Chap. 2, this Vol.). Restoration objectives may include increasing population numbers to reduce extinction probability, deterministic manipulations to develop a staged cohort structure, or more complex restoration of a desired genetic structure to allow outcrossing or increase effective population size (DeMauro 1993, 1994; Bowles et al. 1993, 1998; Pavlik 1994; Knapp and Dyer 1998; Chap. 2, this Vol.). These efforts may require translocation of propagules from existing (in situ) populations, or from ex situ botanic gardens or seed storage facilities (Falk et al. 1996; Guerrant and Pavlik 1998; Chap. 2, this Vol.). Population viability analysis (PVA) can provide a critical foundation for plant restoration, as it models demographic projections used to evaluate the probability of population persistence and links plant life history with restoration strategies. It is unknown how well artificially created populations will meet demographic modeling requirements (e.g., due to artificial cohort transitions) and few, if any, PVAs have been applied to restorations. To guide application of PVA to restored populations and to illustrate potential difficulties, we examine effects of planting different life stages, model initial population sizes needed to achieve population viability, and compare demographic characteristics between natural and restored populations. We develop and compare plant population restoration viability analysis (PRVA) case studies of

  5. Evolution of recombination rates in a multi-locus, haploid-selection, symmetric-viability model.

    PubMed

    Chasnov, J R; Ye, Felix Xiaofeng

    2013-02-01

    A fast algorithm for computing multi-locus recombination is extended to include a recombination-modifier locus. This algorithm and a linear stability analysis is used to investigate the evolution of recombination rates in a multi-locus, haploid-selection, symmetric-viability model for which stable equilibria have recently been determined. When the starting equilibrium is symmetric with two selected loci, we show analytically that modifier alleles that reduce recombination always invade. When the starting equilibrium is monomorphic, and there is a fixed nonzero recombination rate between the modifier locus and the selected loci, we determine analytical conditions for which a modifier allele can invade. In particular, we show that a gap exists between the recombination rates of modifiers that can invade and the recombination rate that specifies the lower stability boundary of the monomorphic equilibrium. A numerical investigation shows that a similar gap exists in a weakened form when the starting equilibrium is fully polymorphic but asymmetric.

  6. Viability of Cladosporium herbarum spores under 157 nm laser and vacuum ultraviolet irradiation, low temperature (10 K) and vacuum

    NASA Astrophysics Data System (ADS)

    Sarantopoulou, E.; Stefi, A.; Kollia, Z.; Palles, D.; Petrou, P. S.; Bourkoula, A.; Koukouvinos, G.; Velentzas, A. D.; Kakabakos, S.; Cefalas, A. C.

    2014-09-01

    Ultraviolet photons can damage microorganisms, which rarely survive prolonged irradiation. In addition to the need for intact DNA, cell viability is directly linked to the functionality of the cell wall and membrane. In this work, Cladosporium herbarum spore monolayers exhibit high viability (7%) when exposed to 157 nm laser irradiation (412 kJm-2) or vacuum-ultraviolet irradiation (110-180 nm) under standard pressure and temperature in a nitrogen atmosphere. Spore viability can be determined by atomic-force microscopy, nano-indentation, mass, μ-Raman and attenuated reflectance Fourier-transform far-infrared spectroscopies and DNA electrophoresis. Vacuum ultraviolet photons cause molecular damage to the cell wall, but radiation resistance in spores arises from the activation of a photon-triggered signaling reaction, expressed via the exudation of intracellular substances, which, in combination with the low penetration depth of vacuum-ultraviolet photons, shields DNA from radiation. Resistance to phototoxicity under standard conditions was assessed, as was resistance to additional environmental stresses, including exposure in a vacuum, under different rates of change of pressure during pumping time and low (10 K) temperatures. Vacuum conditions were far more destructive to spores than vacuum-ultraviolet irradiation, and UV-B photons were two orders of magnitude more damaging than vacuum-ultraviolet photons. The viability of irradiated spores was also enhanced at 10 K. This work, in addition to contributing to the photonic control of the viability of microorganisms exposed under extreme conditions, including decontamination of biological warfare agents, outlines the basis for identifying bio-signaling in vivo using physical methodologies.

  7. Viability of Cladosporium herbarum spores under 157 nm laser and vacuum ultraviolet irradiation, low temperature (10 K) and vacuum

    SciTech Connect

    Sarantopoulou, E. Stefi, A.; Kollia, Z.; Palles, D.; Cefalas, A. C.; Petrou, P. S.; Bourkoula, A.; Koukouvinos, G.; Kakabakos, S.; Velentzas, A. D.

    2014-09-14

    Ultraviolet photons can damage microorganisms, which rarely survive prolonged irradiation. In addition to the need for intact DNA, cell viability is directly linked to the functionality of the cell wall and membrane. In this work, Cladosporium herbarum spore monolayers exhibit high viability (7%) when exposed to 157 nm laser irradiation (412 kJm⁻²) or vacuum-ultraviolet irradiation (110–180 nm) under standard pressure and temperature in a nitrogen atmosphere. Spore viability can be determined by atomic-force microscopy, nano-indentation, mass, μ-Raman and attenuated reflectance Fourier-transform far-infrared spectroscopies and DNA electrophoresis. Vacuum ultraviolet photons cause molecular damage to the cell wall, but radiation resistance in spores arises from the activation of a photon-triggered signaling reaction, expressed via the exudation of intracellular substances, which, in combination with the low penetration depth of vacuum-ultraviolet photons, shields DNA from radiation. Resistance to phototoxicity under standard conditions was assessed, as was resistance to additional environmental stresses, including exposure in a vacuum, under different rates of change of pressure during pumping time and low (10 K) temperatures. Vacuum conditions were far more destructive to spores than vacuum-ultraviolet irradiation, and UV-B photons were two orders of magnitude more damaging than vacuum-ultraviolet photons. The viability of irradiated spores was also enhanced at 10 K. This work, in addition to contributing to the photonic control of the viability of microorganisms exposed under extreme conditions, including decontamination of biological warfare agents, outlines the basis for identifying bio-signaling in vivo using physical methodologies.

  8. Spore Density and Viability of Entomopathogenic Fungal Isolates from Indonesia, and Their Virulence against Aphis gossypii Glover (Homoptera: Aphididae).

    PubMed

    Herlinda, Siti

    2010-08-01

    The focus of this study was on quantifying fitness attributes, such as spore density and viability, and determining the virulence level against aphid (Aphis gossypii) nymphs of isolates from the fungal species Beauveria bassiana and Metarhizium anisopliae. The fungal isolates were obtained from several insects, including Plutella xylostella, Hypothenemus hampei, Bronstispa longissima, A. gossypii, Tenebrio molitor, and Leptocorisa acuta, that were collected from Indonesian islands, such as Sumatera, Java, and Sulawesi. Third instar aphid nymphs were inoculated via topical application of 10(6) conidia ml(-1) of the entomopathogenic fungal isolates. All of the B. bassiana and M. anisopliae isolates could produce very dense spores. The M. anisopliae isolate MaAg, which was obtained from the aphid, had the highest spore density at 6.70 × 10(8) conidia ml(-1). Among the B. bassiana isolates, the highest conidial viability belonged to isolate CPJW8, which was obtained from Chrysodeixis chalcites, with a 39% average viability. Among the M. anisopliae isolates, the highest viabilities belonged to the isolates MaAg and MaLa, which were obtained from L. acuta, with a 33% and 32% average viabilities, respectively. All of the B. bassiana and M. anisopliae isolates were virulent against aphid nymphs, with mortality rates ranging from 64% to 94%. The three most virulent isolates were BBY715 (94%), MPx (92%), and MaTm (92%), and the least virulent isolate was MaLa (64%). BBY715, the most virulent isolate, had the shortest lethal time median (LT50) against aphid nymphs at 2.97 hours, and MaLa had the longest LT50 at 61.81 hours.

  9. Effects of trehalose supplementation on cell viability and oxidative stress variables in frozen-thawed bovine calf testicular tissue.

    PubMed

    Zhang, Xiao-Gang; Wang, Yan-Hua; Han, Cong; Hu, Shan; Wang, Li-Qiang; Hu, Jian-Hong

    2015-06-01

    Trehalose is widely used for cryopreservation of various cells and tissues. Until now, the effect of trehalose supplementation on cell viability and antioxidant enzyme activity in frozen-thawed bovine calf testicular tissue remains unexplored. The objective of the present study was to compare the effect of varying doses of trehalose in cryomedia on cell viability and key antioxidant enzymes activities in frozen-thawed bovine calf testicular tissue. Bovine calf testicular tissue samples were collected and cryopreserved in the cryomedias containing varying doses (0, 5, 10, 15, 20 and 25%; v/v) of trehalose, respectively. Cell viability, total antioxidant capacity (T-AOC) activity, catalase (CAT) activity, superoxide dismutase (SOD) activity, glutathione (GSH) content and malondialdehyde (MDA) content were measured and analyzed. The results showed that cell viability, T-AOC activity, SOD activity, CAT activity and GSH content of frozen-thawed bovine calf testicular tissue was decreased compared with that of fresh group (P<0.05). MDA content in frozen-thawed bovine calf testicular tissue was significantly increased compared with that of fresh group (P<0.05). The cryomedia added 15% trehalose exhibited the greatest percentage of cell viability and antioxidant enzyme activity (SOD and CAT) among frozen-thawed groups (P<0.05). Meanwhile, GSH content was the lowest among frozen-thawed groups (P<0.05). However, there were no significance differences in MDA content among the groups added 10, 15 and 20% trehalose (P>0.05). In conclusion, the cryomedia added 15% trehalose reduced the oxidative stress and improved the cryoprotective effect of bovine calf testicular tissue. Further studies are required to obtain more concrete results on the determination of antioxidant capacity of trehalose in frozen-thawed bovine calf testicular tissue.

  10. Effects of Cartilage Impact with and without Fracture on Chondrocyte Viability and the Release of Inflammatory Markers

    PubMed Central

    Stolberg-Stolberg, Josef A.; Furman, Bridgette D.; Garrigues, N. William; Lee, Jaewoo; Pisetsky, David S.; Stearns, Nancy A; DeFrate, Louis E.; Guilak, Farshid; Olson, Steven A.

    2014-01-01

    Post-traumatic arthritis (PTA) frequently develops after intra-articular fracture of weight bearing joints. Loss of cartilage viability and post-injury inflammation have both been implicated as possible contributing factors to PTA progression. In order to further investigate chondrocyte response to impact and fracture, we have developed a blunt impact model applying 70%, 80% or 90% surface-to-surface compressive strain with or without induction of an articular fracture in a cartilage explant model. Following mechanical loading, chondrocyte viability and apoptosis were assessed. Culture media were evaluated for the release of double-stranded DNA (dsDNA) and immunostimulatory activity via nuclear factor kappa B (NF-κB) activity in Toll-like receptor-expressing Ramos-Blue reporter cells. High compressive strains, with or without articular fracture, resulted in significantly reduced chondrocyte viability. Blunt impact at 70% strain induced a loss in viability over time through a combination of apoptosis and necrosis, whereas blunt impact above 80% strain caused predominantly necrosis. In the fracture model, a high level of primarily necrotic chondrocyte death occurred along the fracture edges. At sites away from the fracture, viability was not significantly different than controls. Interestingly, both dsDNA release and NF-κB activity in Ramos-Blue cells increased with blunt impact, but was only significantly increased in the media from fractured cores. This study indicates that the mechanism of trauma determines the type of chondrocyte death as well as the potential for post-injury inflammation. PMID:23620164

  11. Viability of Stored Rabbit Erythrocytes Carrying Number C3c.

    DTIC Science & Technology

    1984-05-31

    A-A165 440 VIABILITY OF STORED RABBIT ERYTHROCYTES CARRYING NUBR V no C3C(U) MASSACHUSETTS UNIV MEDICAL SCHOOL MORCESTER UNCLRSSIFI 0 SZYMANSKI 31...Carrying No C3c 0 Annual and Final Report Irma 0. Szymanski, M.D. Ln CD May 31, 1984 I Supported by U.S. ARMY MEDICAL RESEARCH AND DEVELOPMENT COMMAND...Fort Detrick, Frederick, Maryland 21701-5012 Contract No. DAMD17-82-C-2150 .TICD ET University of Massachusetts Medical Center .EC, Worcester

  12. Methods for isolation and viability assessment of biological organisms

    DOEpatents

    Letant, Sonia Edith; Baker, Sarah Elyse; Bond, Tiziana; Chang, Allan Shih-Ping

    2015-02-03

    Isolation of biological or chemical organisms can be accomplished using a surface enhanced Raman scattering (SERS) system. The SERS system can be a single or a stacked plurality of photonic crystal membranes with noble-metal lined through pores for flowing analyte potentially containing the biological or chemical organisms. The through pores can be adapted to trap individual biological or chemical organisms and emit SERS spectra, which can then be detected by a detector and further analyzed for viability of the biological or chemical organism.

  13. Effect of microemulsions on cell viability of human dermal fibroblasts

    NASA Astrophysics Data System (ADS)

    Li, Juyi; Mironava, Tatsiana; Simon, Marcia; Rafailovich, Miriam; Garti, Nissim

    Microemulsions are optically clear, thermostable and isotropic mixture consisting of water, oil and surfactants. Their advantages of ease preparation, spontaneous formation, long-term stability and enhanced solubility of bioactive materials make them great potentials as vehicles in food and pharmaceutical applications. In this study, comparative in vitro cytotoxicity tests were performed to select a best formulation of microemulsion with the least toxicity for human dermal fibroblasts. Three different kinds of oils and six different kinds of surfactants were used to form microemulsions by different ratios. The effect of oil type and surfactant type as well as their proportions on cell proliferation and viability were tested.

  14. Short communication: The effect of water temperature on the viability of silage inoculants.

    PubMed

    Mulrooney, C N; Kung, L

    2008-01-01

    The objective of this study was to determine if exposure to high temperatures in water affects the viability of various silage inoculants. Inoculants were enumerated on De Man, Rogosa, Sharpe agar to standardize a final count (colony-forming units) in water such that about 500 mL added to 1 tonne of wet forage would achieve a recommended application rate of about 100,000 cfu of lactic acid bacteria (LAB) per gram of wet forage. Testing was done in 4 sequences (SEQ). For each SEQ, inoculants were mixed in deionized water for 45 min at 30 degrees C followed by incubation for 6 h at 30 degrees C (SEQ 1), 35 degrees C (SEQ 2), 40 degrees C (SEQ 3), or 45 degrees C (SEQ 4) in duplicate 125-mL flasks rotating at 125 rpm. After 6 h, rotation was stopped and the temperature was lowered to 30 degrees C for the next 18 h for all SEQ. Numbers of LAB were enumerated at 0, 3, 6, and 24 h. Each sequence was repeated twice. Incubation at a moderate temperature (SEQ 1) did not affect the viability of the microbial inoculants. The viability of the inoculants declined with increasing temperature (SEQ 2 to 4) but the effect varied by inoculant. For some inoculants exposure to 35 degrees C resulted in substantial decreases in viable cells (loss of 0.5 to 1 log cfu/mL). Incubation at higher temperatures resulted in even greater losses in viability for some inoculants. Losses of more than 0.5 log cfu/mL would most likely make the application of these inoculants ineffective in the field. Lactobacillus plantarum MTD/1 was the most thermotolerant organism tested, because it was unaffected by all temperatures (30 to 45 degrees C) after 3 h of incubation. Lactobacillus plantarum MTD/1 and Lactobacillus buchneri 40788 also appeared to have better thermotolerance as their numbers substantially increased between 6 and 24 h in SEQ 4. These data show that some silage inoculants are more thermotolerant than others and that precautions should be taken to ensure that microbial inoculants that are

  15. Applications of a rapid endospore viability assay for monitoring UV inactivation and characterizing arctic ice cores.

    PubMed

    Shafaat, Hannah S; Ponce, Adrian

    2006-10-01

    We have developed a rapid endospore viability assay (EVA) in which endospore germination serves as an indicator for viability and applied it to (i) monitor UV inactivation of endospores as a function of dose and (ii) determine the proportion of viable endospores in arctic ice cores (Greenland Ice Sheet Project 2 [GISP2] cores; 94 m). EVA is based on the detection of dipicolinic acid (DPA), which is released from endospores during germination. DPA concentrations were determined using the terbium ion (Tb3+)-DPA luminescence assay, and germination was induced by L-alanine addition. The concentrations of germinable endospores were determined by comparison to a standard curve. Parallel EVA and phase-contrast microscopy experiments to determine the percentage of germinable spores yielded comparable results (54.3% +/- 3.8% and 48.9% +/- 4.5%, respectively), while only 27.8% +/- 7.6% of spores produced CFU. EVA was applied to monitor the inactivation of spore suspensions as a function of UV dose, yielding reproducible correlations between EVA and CFU inactivation data. The 90% inactivation doses were 2,773 J/m2, 3,947 J/m2, and 1,322 J/m2 for EVA, phase-contrast microscopy, and CFU reduction, respectively. Finally, EVA was applied to quantify germinable and total endospore concentrations in two GISP2 ice cores. The first ice core contained 295 +/- 19 germinable spores/ml and 369 +/- 36 total spores/ml (i.e., the percentage of germinable endospores was 79.9% +/- 9.3%), and the second core contained 131 +/- 4 germinable spores/ml and 162 +/- 17 total spores/ml (i.e., the percentage of germinable endospores was 80.9% +/- 8.8%), whereas only 2 CFU/ml were detected by culturing.

  16. China Report, Economic Affairs.

    DTIC Science & Technology

    2007-11-02

    This is China Report include Economic Affairs. It contains the issues with different topics on People’s Republic of China: Provincial Affairs, Economic Planning, Economic Management, Finance and Banking, Mineral Resources , Industry, Transportation.

  17. Effects of borate-based bioactive glass on neuron viability and neurite extension.

    PubMed

    Marquardt, Laura M; Day, Delbert; Sakiyama-Elbert, Shelly E; Harkins, Amy B

    2014-08-01

    Bioactive glasses have recently been shown to promote regeneration of soft tissues by positively influencing tissue remodeling during wound healing. We were interested to determine whether bioactive glasses have the potential for use in the treatment of peripheral nerve injury. In these experiments, degradable bioactive borate glass was fabricated into rods and microfibers. To study the compatibility with neurons, embryonic chick dorsal root ganglia (DRG) were cultured with different forms of bioactive borate glass. Cell viability was measured with no media exchange (static condition) or routine media exchange (transient condition). Neurite extension was measured within fibrin scaffolds with embedded glass microfibers or aligned rod sheets. Mixed cultures of neurons, glia, and fibroblasts growing in static conditions with glass rods and microfibers resulted in decreased cell viability. However, the percentage of neurons compared with all cell types increased by the end of the culture protocol compared with culture without glass. Furthermore, bioactive glass and fibrin composite scaffolds promoted neurite extension similar to that of control fibrin scaffolds, suggesting that glass does not have a significant detrimental effect on neuronal health. Aligned glass scaffolds guided neurite extension in an oriented manner. Together these findings suggest that bioactive glass can provide alignment to support directed axon growth.

  18. A viability assay for Candida albicans based on the electron transfer mediator 2,6-dichlorophenolindophenol.

    PubMed

    Hassan, Rabeay Y A; Bilitewski, Ursula

    2011-12-01

    Candida albicans is an opportunistic fungal pathogen with comparably high respiratory activity. Thus, we established a viability test based on 2,6-dichlorophenolindophenol (DCIP), a membrane-permeable electron transfer agent. NADH dehydrogenases catalyze the reduction of DCIP by NADH, and the enzymatic activity can be determined either electrochemically via oxidation reactions of DCIP or photometrically. Among the specific respiratory chain inhibitors, only the complex I inhibitor rotenone decreased the DCIP signal from C. albicans, leaving residual activity of approximately 30%. Thus, the DCIP-reducing activity of C. albicans was largely dependent on complex I activity. C. albicans is closely related to the complex I-negative yeast Saccharomyces cerevisiae, which had previously been used in DCIP viability assays. Via comparative studies, in which we included the pathogenic complex I-negative yeast Candida glabrata, we could define assay conditions that allow a distinction of complex I-negative and -positive organisms. Basal levels of DCIP turnover by S.cerevisiae and C. glabrata were only 30% of those obtained from C. albicans but could be increased to the C. albicans level by adding glucose. No significant increases were observed with galactose. DCIP reduction rates from C. albicans were not further increased by any carbon source.

  19. Application of cyclic biamperometry to viability and cytotoxicity assessment in human corneal epithelial cells.

    PubMed

    Rahimi, Mehdi; Youn, Hyun-Yi; McCanna, David J; Sivak, Jacob G; Mikkelsen, Susan R

    2013-05-01

    The application of cyclic biamperometry to viability and cytotoxicity assessments of human corneal epithelial cells has been investigated. Electrochemical measurements have been compared in PBS containing 5.0 mM glucose and minimal essential growth medium. Three different lipophilic mediators including dichlorophenol indophenol, 2-methyl-1,4-naphthoquinone (also called menadione or vitamin K3) and N,N,N',N'-tetramethyl-p-phenylenediamine have been evaluated for shuttling electrons across the cell membrane to the external medium. Transfer of these electrons to ferricyanide in the extra cellular medium results in the accumulation of ferrocyanide. The amount of ferrocyanide is then determined using cyclic biamperometry and is related to the extent of cell metabolic activity and therefore cell viability. To illustrate cytotoxicity assessment of chemicals, hydrogen peroxide, benzalkonium chloride and sodium dodecyl sulfate have been chosen as sample toxins, the cytotoxicities of which have been evaluated and compared to values reported in the literature. Similar values have been reported using colorimetric assays; however, the simplicity of this electrochemical assay can, in principle, open the way to miniaturization onto lab-on-chip devices and its incorporation into tiered-testing approaches for cytotoxicity assessment.

  20. Impacts of viability and purification on the specific gravity of Cryptosporidium oocysts.

    PubMed

    Young, Pamela L; Komisar, Simeon J

    2005-09-01

    The specific gravity of unpurified and purified Cryptosporidium oocysts was measured using an isopycnic gradient centrifugation technique. Specific gravity varied depending on the viability of the oocysts, as defined by permeabilty to 4',6-diamidino-2-phenylindole (DAPI) and propidium iodide (PI), the presence or absence of internal structures, and whether or not oocysts were purified. The modal range of densities for a population of 1.4-week-old unpurified oocysts, was 1070-1073 kg/m3. This range was higher than that determined for 14-week-old purified oocysts, 1067-1070 kg/m3. Eleven- and 12-week-old unpurified populations exhibited a bimodal distribution of densities, with densities most frequently in the 1005-1041 and in the 1077-1108 kg/m3 range. In these populations, a high percentage of the oocysts having densities greater than 1077 kg/m3 were viable, while oocysts in the 1005-1024 kg/m3 range were predominately nonintact, and oocysts in the 1024-1041 kg/m3 range were intact, but permeable to DAPI and PI (nonviable). This work demonstrates the importance of controlling factors that may impact the viability of oocysts when conducting studies that examine the transport of these microorganisms in the environment and through water treatment processes.

  1. Antigenicity and viability of Anisakis larvae infesting hake heated at different time-temperature conditions.

    PubMed

    Vidacek, Sanja; de las Heras, Cristina; Solas, Maria Teresa; Mendizábal, Angel; Rodriguez-Mahillo, Ana I; Tejada, Margarita

    2010-01-01

    Heat treatments (40 to 94 degrees Celsius, 30 s to 60 min) were applied to different batches of Anisakis simplex L3 larvae isolated from hake ovaries and viscera to study the effect of heat on the viability of the larvae measured as mobility, emission of fluorescence under UV light, and changes in color after staining with specific dyes, and on A. simplex antigenic proteins. The aim was to determine the lowest time-temperature conditions needed to kill the larvae to avoid anisakiasis in consumers, and to evaluate whether high temperature modifies the antigenicity of A. simplex extracts. Heating at 60 degrees Celsius for 10 min (recommended by some authors) was considered unsafe, as differences in viability between batches were found, with some larvae presenting spontaneous movements in one batch. At higher temperatures (> or = 70 degrees Celsius for > or = 1 min), no movement of the larvae was observed. Antigenic protein Ani s 4 and A. simplex crude antigens were detected in the larvae heated at 94 + or - 1 degrees Celsius for 3 min. This indicates that allergic symptoms could be provoked in previously sensitized consumers, even if the larvae were killed by heat treatment.

  2. Opiates do not violate the viability and proliferative activity of human articular chondrocytes.

    PubMed

    Chechik, Ofir; Arbel, Ron; Salai, Moshe; Gigi, Roy; Beilin, Mark; Flaishon, Ron; Sever, Ronen; Khashan, Morsi; Ben-Tov, Tomer; Gal-Levy, Ronit; Yayon, Avner; Blumenstein, Sara

    2014-09-01

    Articular cartilage injuries present a challenge for the clinician. Autologous chondrocyte implantation embedded in scaffolds are used to treat cartilage defects with favorable outcomes. Autologous serum is often used as a medium for chondrocyte cell culture during the proliferation phase of the process of such products. A previous report showed that opiate analgesics (fentanyl, alfentanil and diamorphine) in the sera have a significant inhibitory effect on chondrocyte proliferation. In order to determine if opiates in serum inhibit chondrocyte proliferation, twenty two patients who underwent knee arthroscopy and were anesthetized with either fentanyl or remifentanil were studied. Blood was drawn before and during opiate administration and up to 2 h after its discontinuation. The sera were used as medium for in vitro proliferation of both cryopreserved and freshly isolated chondrocytes, and the number and viability of cells were measured. There was no difference in the yield or cell viability between the serum samples of patients anesthetized with fentanyl when either fresh or cryopreserved human articular chondrocytes (hACs) were used. Some non-significant reduction in the yield of cells was observed in the serum samples of patients anesthetized with remifentanil when fresh hAC were used. We conclude that Fentanyl in human autologous serum does not inhibit in vitro hAC proliferation. Remifentanil may show minimal inhibitory effect on in vitro fresh hAC proliferation.

  3. Metabolic activity of sperm cells: correlation with sperm cell concentration, viability and motility in the rabbit.

    PubMed

    Sabés-Alsina, Maria; Planell, Núria; Gil, Sílvia; Tallo-Parra, Oriol; Maya-Soriano, Maria José; Taberner, Ester; Piles, Miriam; Sabés, Manel; Lopez-Bejar, Manel

    2016-10-01

    The resazurin reduction test (RRT) is a useful technique to assess the metabolic rate of sperm cells. RRT depends on the ability of metabolically active cells to reduce the non-fluorescent dye resazurin to the fluorescent resorufin. The aim of this study was to develop a vital fluorometric method to evaluate metabolic activity of rabbit sperm cells. Twenty-five rabbit males were included in the study. Viability and morphology, motility and metabolic activity were evaluated using an eosin-nigrosin staining, a computer-assisted semen analysis (CASA) and the RRT, respectively. Spearman rank correlation analysis was used to determine the correlation between RRT and semen parameters. After evaluation, a concentration of 10 × 106 sperm cells/ml was selected for further experiments with RRT. No significant correlation was found between the RRT results and the motility parameters. However, after RRT a significant positive correlation between relative fluorescence units and the percentage of alive spermatozoa (r = 0.62; P = 0.001) and a negative one with the percentage of sperm cells with acrosomic abnormalities (r = -0.45; P < 0.05) were detected. The vital assessment of metabolic rate of sperm cells by RRT could provide more information about semen quality than other routine semen analysis, correlating with sperm viability and acrosome status information.

  4. Pressurized liquid extraction of Aglaonema sp. iminosugars: Chemical composition, bioactivity, cell viability and thermal stability.

    PubMed

    Rodríguez-Sánchez, S; Martín-Ortiz, A; Carrero-Carralero, C; Ramos, S; Sanz, M L; Soria, A C

    2016-08-01

    Pressurized liquid extraction of Aglaonema sp. iminosugars has been optimized. A single cycle under optimal conditions (80mg, 100°C, 2min) was enough to extract ⩾96% of most iminosugars. Further incubation with Saccharomyces cerevisiae for 5h removed coextracted interfering low molecular weight carbohydrates from extracts of different Aglaonema cultivars. A complete characterization of these extracts was carried out by gas chromatography-mass spectrometry: three iminosugars were tentatively identified for the first time; α-homonojirimycin and 2,5-dideoxy-2,5-imino-d-mannitol were the major iminosugars determined. α-Glucosidase inhibition activity, cell viability and thermal stability of Aglaonema extracts were also evaluated. Extracts with IC50 for α-glucosidase activity in the 0.010-0.079mgmL(-1) range showed no decrease of Caco-2 cell viability at concentrations lower than 125μgmL(-1) and were stable at 50°C for 30days. These results highlight the potential of Aglaonema extracts as a source of bioactives to be used as functional ingredients.

  5. Candida albicans RHO1 is required for cell viability in vitro and in vivo.

    PubMed

    Smith, Susan E; Csank, Csilla; Reyes, Guadalupe; Ghannoum, Mahmoud A; Berlin, Vivian

    2002-05-01

    In Saccharomyces cerevisiae, Rho1p plays an important role in cell wall integrity by regulating beta-1,3-glucan synthase, Pkc1p and the actin cytoskeleton. To determine the physiological role of Rho1p in the dimorphic fungus Candida albicans, the major human fungal pathogen, we constructed mutants that conditionally express Rho1p from the glucose-repressible phosphoenolpyruvate carboxykinase promoter (pPCK1). We examined the growth of these cells in a range of conditions. Depletion of Rho1p from yeast cells resulted in cell death, lysis, and aggregation. The Rho1p conditional mutant was inviable on 10% serum indicating that Rho1p was also required for hyphal viability. Furthermore, in a mouse model of systemic candidiasis, strains dependent on pPCK1-driven RHO1 expression failed to colonise the kidneys and establish disease, suggesting that the level of glucose in serum was sufficient to repress the pPCK1 and that Rho1p-depleted strains were inviable within the host. Therefore, Rho1p is essential for the viability of C. albicans in vitro and in vivo.

  6. Monitoring of microbial cell viability using nanostructured electrodes modified with Graphene/Alumina nanocomposite.

    PubMed

    Hassan, Rabeay Y A; Mekawy, Moataz M; Ramnani, Pankaj; Mulchandani, Ashok

    2017-05-15

    Microbial infections are rapidly increasing; however most of the existing microbiological and molecular detection methods are time consuming and/or cannot differentiate between the viable and dead cells which may overestimate the risk of infections. Therefore, a bioelectrochemical sensing platform with a high potential to the microbial-electrode interactions was designed based on decorated graphene oxide (GO) sheet with alumina (Al2O3) nanocrystals. GO-Al2O3 nanocomposite was synthesized using self-assembly of GO and Al2O3 and characterized using the scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), Raman-spectroscopy, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Enhancement of electrocatalytic activity of the composite-modified electrode was demonstrated. Thus, using the GO-Al2O3 nanocomposite modified electrode, the cell viability was determined by monitoring the bioelectrochemical response of the living microbial cells (bacteria and yeast) upon stimulation with carbon source. The bioelectrochemical assay was optimized to obtain high sensitivity and the method was applied to monitor cell viability and screen susceptibility of metabolically active cells (E. coli, B. subtilis, Enterococcus, P. aeruginosa and Salmonella typhi) to antibiotics such as ampicillin and kanamycin. Therefore, the developed assay is suitable for cell proliferation and cytotoxicity testing.

  7. Ischemia-reperfusion model in rat spinal cord: cell viability and apoptosis signaling study

    PubMed Central

    de Lavor, Mário Sérgio Lima; Binda, Nancy Scardua; Fukushima, Fabíola Bono; Caldeira, Fátima Maria Caetano; da Silva, Juliana Figueira; Silva, Carla Maria Osório; de Oliveira, Karen Maciel; Martins, Bernardo de Caro; Torres, Bruno Benetti Junta; Rosado, Isabel Rodrigues; Gomez, Renato Santiago; Gomez, Marcus Vinícius; de Melo, Eliane Gonçalves

    2015-01-01

    This work aimed at determining the ideal ischemia time in an in vitro ischemia-reperfusion model of spinal cord injury. Rat spinal cord slices were prepared and then exposed or not to oxygen deprivation and low glucose (ODLG) for 30, 45, 60, 75 and 90 minutes. Cell viability was assessed by triphenyltetrazolium (TTC), lactate dehydrogenase (LDH) release, and fluorochrome dyes specific for cell dead (ethidium homodimer) using the apotome system. Glutamate release was enzymatically measured by a fluorescent method. Gene expression of apoptotic factors was assessed by real time RT-PCR. Whereas spinal cord slices exposed to ODLG exhibited mild increase in fluorescence for 30 minutes after the insult, the 45, 60, 75 and 90 minutes caused a 2-fold increase. ODLG exposure for 45, 60, 75 or 90 minutes, glutamate and LDH release were significantly elevated. nNOS mRNA expression was overexpressed for 45 minutes and moderately increased for 60 minutes in ODLG groups. Bax/bcl-xl ratio, caspase 9 and caspase 3 mRNA expressions were significantly increased for 45 minutes of ODLG, but not for 30, 60, 75 and 90 minutes. Results showed that cell viability reduction in the spinal cord was dependent on ischemic time, resulting in glutamate and LDH release. ODLG for 45 minutes was adequate for gene expression evaluation of proteins and proteases involved in apoptosis pathways. PMID:26617703

  8. Viability of the Alaskan breeding population of Steller’s eiders

    USGS Publications Warehouse

    Dunham, Kylee; Grand, James B.

    2016-10-11

    The U.S. Fish and Wildlife Service is tasked with setting objective and measurable criteria for delisting species or populations listed under the Endangered Species Act. Determining the acceptable threshold for extinction risk for any species or population is a challenging task, particularly when facing marked uncertainty. The Alaskan breeding population of Steller’s eiders (Polysticta stelleri) was listed as threatened under the Endangered Species Act in 1997 because of a perceived decline in abundance throughout their nesting range and geographic isolation from the Russian breeding population. Previous genetic studies and modeling efforts, however, suggest that there may be dispersal from the Russian breeding population. Additionally, evidence exists of population level nonbreeding events. Research was conducted to estimate population viability of the Alaskan breeding population of Steller’s eiders, using both an open and closed model of population process for this threatened population. Projections under a closed population model suggest this population has a 100 percent probability of extinction within 42 years. Projections under an open population model suggest that with immigration there is no probability of permanent extinction. Because of random immigration process and nonbreeding behavior, however, it is likely that this population will continue to be present in low and highly variable numbers on the breeding grounds in Alaska. Monitoring the winter population, which includes both Russian and Alaskan breeding birds, may offer a more comprehensive indication of population viability.

  9. Bcl-2 expression in synovial fibroblasts is essential for maintaining mitochondrial homeostasis and cell viability.

    PubMed

    Perlman, H; Georganas, C; Pagliari, L J; Koch, A E; Haines, K; Pope, R M

    2000-05-15

    The regulation of proliferation and cell death is vital for homeostasis, but the mechanism that coordinately balances these events in rheumatoid arthritis (RA) remains largely unknown. In RA, the synovial lining thickens in part through increased proliferation and/or decreased synovial fibroblast cell death. Here we demonstrate that the anti-apoptotic protein, Bcl-2, is highly expressed in RA compared with osteoarthritis synovial tissues, particularly in the CD68-negative, fibroblast-like synoviocyte population. To determine the importance of endogenous Bcl-2, an adenoviral vector expressing a hammerhead ribozyme to Bcl-2 (Ad-Rbz-Bcl-2) mRNA was employed. Ad-Rbz-Bcl-2 infection resulted in reduced Bcl-2 expression and cell viability in synovial fibroblasts isolated from RA and osteoarthritis synovial tissues. In addition, Ad-Rbz-Bcl-2-induced mitochondrial permeability transition, cytochrome c release, activation of caspases 9 and 3, and DNA fragmentation. The general caspase inhibitor zVAD.fmk blocked caspase activation, poly(ADP-ribose) polymerase cleavage, and DNA fragmentation, but not loss of transmembrane potential or viability, indicating that cell death was independent of caspase activation. Ectopically expressed Bcl-xL inhibited Ad-Rbz-Bcl-2-induced mitochondrial permeability transition and apoptosis in Ad-Rbz-Bcl-2-transduced cells. Thus, forced down-regulation of Bcl-2 does not induce a compensatory mechanism to prevent loss of mitochondrial integrity and cell death in human fibroblasts.

  10. Exposure to the proton scavenger glycine under alkaline conditions induces Escherichia coli viability loss.

    PubMed

    Vanhauteghem, Donna; Janssens, Geert Paul Jules; Lauwaerts, Angelo; Sys, Stanislas; Boyen, Filip; Cox, Eric; Meyer, Evelyne

    2013-01-01

    Our previous work described a clear loss of Escherichia coli (E. coli) membrane integrity after incubation with glycine or its N-methylated derivatives N-methylglycine (sarcosine) and N,N-dimethylglycine (DMG), but not N,N,N-trimethylglycine (betaine), under alkaline stress conditions. The current study offers a thorough viability analysis, based on a combination of real-time physiological techniques, of E. coli exposed to glycine and its N-methylated derivatives at alkaline pH. Flow cytometry was applied to assess various physiological parameters such as membrane permeability, esterase activity, respiratory activity and membrane potential. ATP and inorganic phosphate concentrations were also determined. Membrane damage was confirmed through the measurement of nucleic acid leakage. Results further showed no loss of esterase or respiratory activity, while an instant and significant decrease in the ATP concentration occurred upon exposure to either glycine, sarcosine or DMG, but not betaine. There was a clear membrane hyperpolarization as well as a significant increase in cellular inorganic phosphate concentration. Based on these results, we suggest that the inability to sustain an adequate level of ATP combined with a decrease in membrane functionality leads to the loss of bacterial viability when exposed to the proton scavengers glycine, sarcosine and DMG at alkaline pH.

  11. Viability of probiotic (Bifidobacterium, Lactobacillus acidophilus and Lactobacillus casei) and nonprobiotic microflora in Argentinian Fresco cheese.

    PubMed

    Vinderola, C G; Prosello, W; Ghiberto, T D; Reinheimer, J A

    2000-09-01

    We evaluated the suitability of Argentinian Fresco cheese as a food carrier of probiotic cultures. We used cultures of Bifidobacterium bifidum (two strains), Bifidobacterium longum (two strains), Bifidobacterium sp. (one strain), Lactobacillus acidophilus (two strains), and Lactobacillus casei (two strains) in different combinations, as probiotic adjuncts. Probiotic, lactic starter (Lactococcus lactis and Streptococcus thermophilus), and contaminant (coliforms, yeasts, and molds) organisms were counted at 0, 30, and 60 d of refrigerated storage. Furthermore, the acid resistance of probiotic and starter bacteria was determined from hydrochloric solutions (pH 2 and 3) of Fresco cheese. The results showed that nine different combinations of bifidobacteria and L. acidophilus had a satisfactory viability (count decreases in 60 d <1 log order) in the cheese. Both combinations of bifidobacteria and L. casei cultures assayed also showed a satisfactory survival (counts decreased <1 log order for bifidobacteria but no decrease was detected for L. casei). On the other hand, the three combinations of bifidobacteria, L. acidophilus, and L. casei tested adapted well to the Fresco cheese environment. When a cheese homogenate at pH 3 was used to partially simulate the acidic conditions in the stomach, the probiotic cultures had an excellent ability to remain viable up to 3 h. At pH 2, the cell viability was more affected; B. bifidum was the most resistant organism. This study showed that the Argentinian Fresco cheese could be used as an adequate carrier of probiotic bacteria.

  12. Study of the competitive viability of minority fuel oil marketers. Final report

    SciTech Connect

    1981-09-30

    Previous studies on the competitive viability of the fuel oil heating market had addressed some of the unique problems facing minority fuel oil marketers (MFMs) within the total market sector (TMS). This study focused on identifying and developing quantitative information on MFMs in the TMS. The specific objective was to determine whether the business problems experienced by MFMs were directly related to their minority status or were characterstic of any firm in the TMS operating under comparable conditions. As an overall conclusion, thorough investigation of the MFMs considered to constitute the universe of minoriy firms within the TMS did not reveal any evidence of overt discrimination affecting the competitive viability of MFMs. Upon analysis, the problems reported by MFMs could not be reasonably ascribed to discrimination on the basis of their minority business status. The study, however, did point up problems unique to MFMs as the result of typical operational and financial characteristics. For example, MFMs, compared to the TMS norm, have not been in the market as long and are smaller in terms of total assets, number of employees, number of trucks, number of accounts and annual volume of oil delivered. Their primary customers are low-income families in urban areas. Financial indicators suggest that the average MFM does not have long-term financial stability. The basis for this overall conclusion, derived by analyses of information from MFMs, as well as many independent sources, is summarized in three parts: (1) MFM industry profile; (2) financial analyses; and (3) problem analyses.

  13. Monitoring water supplies for weaponized bacteria and bacterial toxins using rapid fluorescence-based viability and affinity assays

    NASA Astrophysics Data System (ADS)

    Van Tassell, Roger L.; Evans, Mishell

    2004-03-01

    The rapid detection of weaponized bacteria and toxins is a major problem during a biological attack. Although sensitive detection formats exist for many biowarfare agents, they often require advanced training and complex procedures. Luna has developed simple, rapid means for determining the presence of pathogens and bacterial toxins in water supplies using fluorescence-based assays that can be adapted for field use. The batteries of rapid assays are designed for i) determining cell viability and bacterial loads by exploiting metabolic markers (e.g., acid-production, redox potentials, etc) and ii) detecting bacterial toxins using fluorescent, polymerized affinity liposomes (fluorosomes). The viability assays were characterized using E. coli, S. aureus and the anthrax simulant, B. globigii. The viability assays detected bacterial loads of ~ 104 CFU/ml and with simple filtration ~ 100CFU/ml could be detected. The affinity fluorosomes were characterized using cholera toxin (CT). Affinity liposomes displaying GM1 and anti-CT antibodies could detect CT at <μg/ml levels. Stability studies showed that affinity vesicles could be stored for weeks at 4°C or freeze-dried with no significant loss of binding capacity. Using an in-house fiber optic fluorescence system, Luna characterized the binding of affinity fluorosomes to respective targets and determined the responses of bacterial loads in the fluorescent viability assays. Using this two-tiered approach, Luna demonstrated that water susceptible to sabotage could be easily monitored and confirmed for specific agents using simple, general and specific fluorescence-based detection schemes based on metabolism and ligand-target interactions.

  14. Technical and economic analyses of hydrogen production via indirectly heated gasification and pyrolysis

    SciTech Connect

    Mann, M.K.

    1995-09-01

    Technoeconomic analyses have been conducted on two processes to produce hydrogen from biomass: indirectly-heated gasification of biomass followed by steam reforming of the syngas, and biomass pyrolysis followed by steam reforming of the pyrolysis oil. The analysis of the gasification-based process was highly detailed, including a process flowsheet, material and energy balances calculated with a process simulation program, equipment cost estimation, and the determination of the necessary selling price of hydrogen. The pyrolysis-based process analysis was of a less detailed nature, as all necessary experimental data have not been obtained; this analysis is a follow-up to the preliminary economic analysis presented at the 1994 Hydrogen Program Review. A coproduct option in which pyrolysis oil is used to produce hydrogen and a commercial adhesive was also studied for economic viability. Based on feedstock availability estimates, three plant sizes were studied: 907 T/day, 272 T/day, and 27 T/day. The necessary selling price of hydrogen produced by steam reforming syngas from the Battelle Columbus Laboratories indirectly heated biomass gasifier falls within current market values for the large and medium size plants within a wide range of feedstock costs. Results show that the small scale plant does not produce hydrogen at economically competitive prices, indicating that if gasification is used as the upstream process to produce hydrogen, local refueling stations similar to current gasoline stations, would probably not be feasible.

  15. Effect of various commercial buffers on sperm viability and capacitation.

    PubMed

    Andrisani, Alessandra; Donà, Gabriella; Ambrosini, Guido; Bonanni, Guglielmo; Bragadin, Marcantonio; Cosmi, Erich; Clari, Giulio; Armanini, Decio; Bordin, Luciana

    2014-08-01

    A wide variety of sperm preparation protocols are currently available for assisted conception. They include density gradient separation and washing methods. Both aim at isolating and capacitating as much motile sperm as possible for subsequent oocyte fertilization. The aim of this study was to examine the effects of four commercial sperm washing buffers on sperm viability and capacitation. Semen samples from 48 healthy donors (normal values of sperm count, motility, morphology, and volume) were analyzed. After separation (density gradient 40/80%), sperm were incubated in various buffers then analysed for reactive oxygen species (ROS) production, viability, tyrosine phosphorylation (Tyr-P), cholera toxin B subunit (CTB) labeling, and the acrosome reaction (AR). The buffers affected ROS generation in various ways resulting either in rapid cell degeneration (when the amount of ROS was too high for cell survival) or the inability of the cells to maintain correct functioning (when ROS were too few). Only when the correct ROS generation curve was maintained, suitable membrane reorganization, evidenced by CTB labeling was achieved, leading to the highest percentages of both Tyr-P- and acrosome-reacted-cells. Distinguishing each particular pathological state of the sperm sample would be helpful to select the preferred buffer treatment since both ROS production and membrane reorganization can be significantly altered by commercial buffers.

  16. Cell Viability and Functionality of Probiotic Bacteria in Dairy Products

    PubMed Central

    Vinderola, Gabriel; Binetti, Ana; Burns, Patricia; Reinheimer, Jorge

    2011-01-01

    Probiotic bacteria, according to the definition adopted by the World Health Organization in 2002, are live microorganisms, which when administered in adequate amounts confer a health benefit to the host. Recent studies show that the same probiotic strain produced and/or preserved under different storage conditions, may present different responses regarding their susceptibility to the adverse conditions of the gastrointestinal tract, its capacity to adhere to the intestinal epithelium, or its immunomodulating capacity, the functionality being affected without changes in cell viability. This could imply that the control of cell viability is not always enough to guarantee the functionality (probiotic capacity) of a strain. Therefore, a new challenge arises for food technologists and microbiologists when it comes to designing and monitoring probiotic food: to be able to monitor the functionality of a probiotic microorganism throughout all the stages the strain goes through from the moment it is produced and included in the food vehicle, until the moment of consumption. Conventional methodological tools or others still to be developed must be used. The application of cell membrane functionality markers, the use of tests of resistance to intestinal barriers, the study of surface properties and the application of in vivo models come together as complementary tools to assess the actual capacity of a probiotic organism in a specific food, to exert functional effects regardless of the number of viable cells present at the moment of consumption. PMID:21833320

  17. Noninvasive diagnosis of seed viability using infrared thermography

    PubMed Central

    Kranner, Ilse; Kastberger, Gerald; Hartbauer, Manfred; Pritchard, Hugh W.

    2010-01-01

    Recent advances in the noninvasive analyses of plant metabolism include stress imaging techniques, mainly developed for vegetative tissues. We explored if infrared thermography can be used to predict whether a quiescent seed will germinate or die upon water uptake. Thermal profiles of viable, aged, and dead Pisum sativum seeds were recorded, and image analysis of 22,000 images per individual seed showed that infrared thermography can detect imbibition- and germination-associated biophysical and biochemical changes. These “thermal fingerprints” vary with viability in this species and in Triticum aestivum and Brassica napus seeds. Thermogenesis of the small individual B. napus seeds was at the limit of the technology. We developed a computer model of “virtual pea seeds,” that uses Monte Carlo simulation, based on the heat production of major seed storage compounds to unravel physico-chemical processes of thermogenesis. The simulation suggests that the cooling that dominates the early thermal profiles results from the dissolution of low molecular-weight carbohydrates. Moreover, the kinetics of the production of such “cooling” compounds over the following 100 h is dependent on seed viability. We also developed a deterministic tool that predicts in the first 3 hours of water uptake, when seeds can be redried and stored again, whether or not a pea seed will germinate. We believe that the early separation of individual, ungerminated seeds (live, aged, or dead) before destructive germination assessment creates unique opportunities for integrative studies on cell death, differentiation, and development. PMID:20133712

  18. Population viability analysis with species occurrence data from museum collections.

    PubMed

    Skarpaas, Olav; Stabbetorp, Odd E

    2011-06-01

    The most comprehensive data on many species come from scientific collections. Thus, we developed a method of population viability analysis (PVA) in which this type of occurrence data can be used. In contrast to classical PVA, our approach accounts for the inherent observation error in occurrence data and allows the estimation of the population parameters needed for viability analysis. We tested the sensitivity of the approach to spatial resolution of the data, length of the time series, sampling effort, and detection probability with simulated data and conducted PVAs for common, rare, and threatened species. We compared the results of these PVAs with results of standard method PVAs in which observation error is ignored. Our method provided realistic estimates of population growth terms and quasi-extinction risk in cases in which the standard method without observation error could not. For low values of any of the sampling variables we tested, precision decreased, and in some cases biased estimates resulted. The results of our PVAs with the example species were consistent with information in the literature on these species. Our approach may facilitate PVA for a wide range of species of conservation concern for which demographic data are lacking but occurrence data are readily available.

  19. Effects of Triclosan on Neural Stem Cell Viability and Survival

    PubMed Central

    Park, Bo Kyung; Gonzales, Edson Luck T.; Yang, Sung Min; Bang, Minji; Choi, Chang Soon; Shin, Chan Young

    2016-01-01

    Triclosan is an antimicrobial or sanitizing agent used in personal care and household products such as toothpaste, soaps, mouthwashes and kitchen utensils. There are increasing evidence of the potentially harmful effects of triclosan in many systemic and cellular processes of the body. In this study, we investigated the effects of triclosan in the survivability of cultured rat neural stem cells (NSCs). Cortical cells from embryonic day 14 rat embryos were isolated and cultured in vitro. After stabilizing the culture, triclosan was introduced to the cells with concentrations ranging from 1 μM to 50 μM and in varied time periods. Thereafter, cell viability parameters were measured using MTT assay and PI staining. TCS decreased the cell viability of treated NSC in a concentration-dependent manner along with increased expressions of apoptotic markers, cleaved caspase-3 and Bax, while reduced expression of Bcl2. To explore the mechanisms underlying the effects of TCS in NSC, we measured the activation of MAPKs and intracellular ROS. TCS at 50 μM induced the activations of both p38 and JNK, which may adversely affect cell survival. In contrast, the activities of ERK, Akt and PI3K, which are positively correlated with cell survival, were inhibited. Moreover, TCS at this concentration augmented the ROS generation in treated NSC and depleted the glutathione activity. Taken together, these results suggest that TCS can induce neurodegenerative effects in developing rat brains through mechanisms involving ROS activation and apoptosis initiation. PMID:26759708

  20. The evolutionary dynamics of haplodiploidy: Genome architecture and haploid viability.

    PubMed

    Blackmon, Heath; Hardy, Nate B; Ross, Laura

    2015-11-01

    Haplodiploid reproduction, in which males are haploid and females are diploid, is widespread among animals, yet we understand little about the forces responsible for its evolution. The current theory is that haplodiploidy has evolved through genetic conflicts, as it provides a transmission advantage to mothers. Male viability is thought to be a major limiting factor; diploid individuals tend to harbor many recessive lethal mutations. This theory predicts that the evolution of haplodiploidy is more likely in male heterogametic lineages with few chromosomes, as genes on the X chromosome are often expressed in a haploid environment, and the fewer the chromosome number, the greater the proportion of the total genome that is X-linked. We test this prediction with comparative phylogenetic analyses of mites, among which haplodiploidy has evolved repeatedly. We recover a negative correlation between chromosome number and haplodiploidy, find evidence that low chromosome number evolved prior to haplodiploidy, and that it is unlikely that diplodiploidy has reevolved from haplodiploid lineages of mites. These results are consistent with the predicted importance of haploid male viability.