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1

Economic viability of cogeneration  

SciTech Connect

This paper relates the incremental heat rate of steam turbines, gas turbines and combined cycle topping units to their economic performance as a function of the available differential between fuel and power costs. A few examples are provided for a simple analysis which lends itself to the quick assessment of the economic viability of a cogeneration plant and its sensitivity to energy cost changes. 4 references, 6 figures.

Gorges, H.A.

1986-03-01

2

Economic Viability and Regional Development.  

National Technical Information Service (NTIS)

An area will be considered developed if all members of its population are able to earn as much as people of comparable ability elsewhere in the national economy, and if regional aggregate welfare is at a maximum. A region will be considered economically v...

S. S. Handel

1966-01-01

3

Economic viability of a wind-powered hydroelectric system  

Microsoft Academic Search

To provide a realistic basis of determining the viability of a wind-powered hydroelectric system at a potential site, an evaluation technique has been developed to determine the ideal combination of models and quantities of various wind energy conversion systems under consideration. Basically, this approach uses a synthesized wind speed time series to simulate the operation of a wind-powered hydroelectric system

E. Cheng

1998-01-01

4

Sperm viability - Determination of sperm viability using fluorescence microscopy  

Technology Transfer Automated Retrieval System (TEKTRAN)

To determine the percentage of viable sperm in a semen sample using stains that differentiates viable (live) sperm from nonviable (dead) sperm. Viable sperm are detected by SYBR-14, which stains the sperm nuclei green. Nonviable sperm are detected by propidium iodide (PI), which stains the sperm red...

5

Purification and viability determinations of plant protoplasts  

Microsoft Academic Search

A method is described for purifying plant protoplasts from cellular and subcellular debris. The procedure utilizes a density buffer containing 9.6% sodium metrizoate and 5.6% Ficoll. The use of fluorescein diacetate for assessing the viability of plant protoplasts is also reported.

P. J. Larkin

1976-01-01

6

Phytoextraction: an assessment of biogeochemical and economic viability  

Microsoft Academic Search

Phytoextraction describes the use of plants to remove metals and other contaminants from soils. This low-cost technology has potential for the in situ remediation of large areas of contaminated land. Despite more than 10 years of intensive research on the subject, very few commercial phytoextraction operations have been realised. Here, we investigate the viability of phytoextraction as an effective land-treatment

Brett Robinson; José-Enrique Fernández; Paula Madejón; Teodoro Marañón; José M. Murillo; Steve Green; Brent Clothier

2003-01-01

7

Economic viability of heat pump desuperheaters for supplying domestic hot water  

Microsoft Academic Search

The heat reclaimer is a heat exchange device that removes superheat from the refrigerant gas in a heat pump or central air conditioning unit and uses that extracted energy to heat water for domestic uses. This analysis examines the energy-saving potential and economic benefit of the heat reclaimer. Energy savings were calculated using a modified bin analytical technique. Economic viability

Olszewski

1984-01-01

8

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

Microsoft Academic Search

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

Al-Salem

1987-01-01

9

Economic viability study of a separate household waste collection in a developing country  

Microsoft Academic Search

This article reports a study of the economic viability of a separate household waste collection project, and considers its social and environmental benefits. The study was developed from the database obtained through the pilot project on separate collections in João Pessoa, the capital of Paraíba, in the northeast region of Brazil. The pilot project had been supported by the local

Heber Pimentel Gomes; Claudia Coutinho Nóbrega

2005-01-01

10

Economic viability analysis of planned WEC system installations for electrical power production  

Microsoft Academic Search

The aim of this investigation is the development and implementation of a general and systematic procedure for the evaluation of the economic viability of planned installations of wind energy converters (WEC) for the purpose of electrical power production. The procedure is based on: the assessment of wind energy potential of an area (of interest); the limitations involved in selecting specific

Demetrios P Papadopoulos; John Ch Dermentzoglou

2002-01-01

11

Viability of Giardia intestinalis Cysts and Viability and Sporulation State of Cyclospora cayetanensis Oocysts Determined by Electrorotation  

PubMed Central

Electrorotation is a noninvasive technique that is capable of detecting changes in the morphology and physicochemical properties of microorganisms. Electrorotation studies are reported for two intestinal parasites, Giardia intestinalis and Cyclospora cayetanensis. It is concluded that viable and nonviable G. intestinalis cysts can be differentiated by this technique, and support for this conclusion was obtained using a fluorogenic vital dye assay and morphological indicators. The viability of C. cayetanensis oocysts (for which no vital dye assay is currently available) can also be determined by electrorotation, as can their sporulation state. Modeling of the electrorotational response of these organisms was used to determine their dielectric properties and to gain an insight into the changes occurring within them. Electrorotation offers a new, simple, and rapid method for determining the viability of parasites in potable water and food products and as such has important healthcare implications.

Dalton, C.; Goater, A. D.; Pethig, R.; Smith, H. V.

2001-01-01

12

Economic viability of stand-alone solar photovoltaic system in comparison with diesel-powered system for India  

Microsoft Academic Search

The economic viability of a stand-alone solar photovoltaic (PV) system with the most likely conventional alternative system, i.e. a diesel-powered system, has been analysed for energy demand through sensitivity analysis using a life-cycle cost computation. The sensitivity analysis allows estimation of the comparative viability of PV against a conventional alternative system based on particular country-specific parameters. The overall PV best

Mohanlal Kolhe; Sunita Kolhe; J. C. Joshi

2002-01-01

13

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

SciTech Connect

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.

Al-Salem, A.M.

1987-01-01

14

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

ERIC Educational Resources Information Center

|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…

Chan, James L.; Snyder, Gerald E.

15

Economical and Technical Viability of a Thermosyphon Solar Water Heater in Cote D` Ivoire  

NASA Astrophysics Data System (ADS)

We propose a comparative study between solar water heater energy and classical sources of domestic hot water production. This study shows that Solar Water Heater (SWH) could be more competitive if the purchase price was reduced. In order to strengthen local technical capacity, to accelerate dissemination and insure appropriation of SWH technology as well as to stimulate acceptance of other solar technologies in Cote d`Ivoire, we propose an innovated design of a thermosyphon solar water heater, using available local materials in order to reduce cost. A prototype of the study SWH has been built and tested experimentally. The results show that the system is suitable for application in Cote d`Ivoire weather conditions. All those performances, combined with manufacturing simplicity and the absence of moving parts, make the system an interesting technological solution. The results can then be used for the dissemination of the system. The economic study confirms the viability and the real potential market of the locally manufactured SWH. The purchase cost is 2.0 times lower than the imported ones.

Sako, M. K.; N`Guessan, Y.; Andoh, H. Y.; Koffi, P. M. E.; Gbaha, P.; Sangare, M. K.

16

[Use of dimiphen blue to determine the viability of mechanically injured tissues].  

PubMed

Results of the experimental use of Dimiphen blue for determination of viability of tissues are presented. Experiments were made in 23 rabbits with standard contusion-crush skin-muscle wounds. the results have shown that the method is good for diagnosis and may be recommended for clinical use. PMID:3992817

Kalnberz, V K; Kalnin, Ia Ia; Stepanova, A A; Amelin, A Z

1985-01-01

17

CASE STUDY: ECONOMIC VIABILITY OF COMPONENT MANAGEMENT FOR A NEW DESIGN  

Microsoft Academic Search

This paper explores the viability of standardization of design and manufacturing techniques to expedite product development and control design proliferation using an example of a leading transport refrigeration unit manufacturer. As an incremental approach to implementing standardization in a product development environment, a conceptual framework for component management decision support system is presented to build a case for its technical

SAMEER KUMAR; CHARU CHANDRA

2001-01-01

18

A Flow Cytometric Method for Rapid Determination of Sperm Concentration and Viability in Mammalian and Avian Semen  

Microsoft Academic Search

A new flow cytometric method has been developed to rapidly determine sperm concentration and viability in semen from bulls and boars. Sperm viability was determined on the basis of stain- ing with SYBR-14 and propidium iodide (PI), and this allowed detec- tion of live (membrane-intact) sperm, dying (moribund) sperm, as well as dead cells. Fluorescent microspheres (beads) were used to

PREBEN CHRISTENSEN; JENS P. STENVANG; WILLIAM L. GODFREY

2004-01-01

19

The economic viability of commercial wind plants in Greece A complete sensitivity analysis  

Microsoft Academic Search

The influence of the governing techno-economic parameters on the economic behaviour of commercial wind parks is investigated. For this purpose, a complete cost–benefit analysis model, properly adapted for the Greek market, is developed in order to calculate the pay-back period and the economic efficiency of similar investments in the energy production sector. Moreover, the impact of various parameters — such

J. K. Kaldellis; Th. J. Gavras

2000-01-01

20

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

Microsoft Academic Search

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

Nicholas Kalaitzandonakes

2005-01-01

21

Social determinants of health: an economic perspective.  

PubMed

The World Health Organization has recently received the findings of its Commission on the Social Determinants of Health. The Commission's report offers a remarkable summary of the evidence, and makes a passionate case for government action to address the social determinants of health, especially as they relate to health inequity. This paper summarizes the ways in which economic analysis could strengthen policy under three headings: examining the causal impact of the determinants of health and of associated policies; prioritizing actions; and determining the role of government in influencing behaviour. PMID:19370713

Epstein, David; Jiménez-Rubio, Dolores; Smith, Peter C; Suhrcke, Marc

2009-05-01

22

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

SciTech Connect

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.

Nicholas Kalaitzandonakes

2005-11-30

23

ECONOMIC VIABILITY OF BT-CORN IN THE U.S  

Microsoft Academic Search

Bt-corn, a genetically engineered insect resistant variety, has been adopted by almost one-quarter of all corn farmers, resulting in economic impacts on both conventional corn growers and Bt-corn growers. we estimate changes in profits for both types of farmers with different levels of seed premiums, yield increases and adoption rates. We find that Bt-corn growers will see their profits decline

Hong-Jin Kim; Kazim Konyar; Keith Sargent

2002-01-01

24

Financial and economic determinants of firm default  

Microsoft Academic Search

This paper investigates the relevance of financial and economic variables as determinants of firm default. Our analysis covers\\u000a a large sample of medium-sized limited liability firms. Since default might lead, through bankruptcy or radical restructuring,\\u000a to firm’s exit, our work also relates to previous contributions on industrial demography. Using non parametric tests we assess\\u000a to what extent defaulting firms differ

Giulio Bottazzi; Marco Grazzi; Angelo Secchi; Federico Tamagni

2011-01-01

25

A Study of the Economics and Environmental Viability of a U.S. Flag Toxic Chemical Incinerator Ship. Volume I: Executive Summary.  

National Technical Information Service (NTIS)

This report details the economic and environmental viability of incinerating toxic chemical wastes at sea using a U.S. flag ship(s). The ocean incineration history in Europe and the United States is reviewed first. The impact of international, national, a...

M. Halebsky

1978-01-01

26

A Study of the Economics and Environmental Viability of a U.S. Flag Toxic Chemical Incinerator Ship. Volume II: Detailed Study.  

National Technical Information Service (NTIS)

This report details the economic and environmental viability of incinerating toxic chemical wastes at sea using a U.S. flag ship(s). The ocean incineration history in Europe and the United States is reviewed first. The impact of international, national, a...

M. Halebsky

1978-01-01

27

Accuracy of three techniques to determine cell viability in 3D tissues or scaffolds.  

PubMed

Several different assays are commonly used to evaluate survival of cells inside tissues or three-dimensional carriers, but their accuracy and reliability have not been evaluated. Here, we compare three methods for cell viability (CV) determination: (i) lactate dehydrogenase (LDH) staining on cryosections, (ii) calcein AM/ethidium homodimer-1 (CaAM/EthH) staining, and (iii) carrier digestion and trypan blue (TB) assay. Living and dead cell populations were generated from bovine chondrocytes and combined to produce approximately 0%, 25%, 50%, 75%, and 100% CV mixtures. CV ratios were measured with TB assay (MIX) before seeding cells into fibrin carriers. CV was then determined using the three methods (n = 5/method). Custom-written macros were used to process LDH- and CaAM/EthH-stained images, and hand counting with hemocytometer was used for the TB method. Absolute error and intraclass correlation (ICC) were used for accuracy and reliability evaluation. All methods estimated CV values close to MIX values. TB method was the most accurate (ICC = 0.99) followed by CaAM/EthH (ICC = 0.98) and LDH (ICC = 0.97). As for absolute quantification of living and dead cells, TB and LDH methods performed well (ICC = 0.75-0.96), whereas CaAM/EthH largely overestimated cell numbers (living, ICC = 0.30; dead, ICC = 0.30). Although TB was the most accurate, LDH and CaAM/EthH provide valuable information on cell shape and spatial distribution of cells in tissue or a scaffold. PMID:18800876

Gantenbein-Ritter, Benjamin; Potier, Esther; Zeiter, Stephan; van der Werf, Marije; Sprecher, Christoph M; Ito, Keita

2008-12-01

28

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

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.

Not Available

1980-09-01

29

Africa's Past Economic Development and its Determinants  

Microsoft Academic Search

From the colonial era to the present, economic progress in sub-Saharan Africa has been slow. This paper argues that Africa's stagnation started be- fore the European expansion and that modern influences are not able to fully account for Africa's growth tragedy. The paper uses measures of urbanization to proxy for economic progress in pre-modern times and shows that before the

Javier A. Birchenall

30

The determination of cellular viability of hybridoma cells in microtitre plates: A colorimetric assay based on neutral red  

Microsoft Academic Search

A colorimetric assay utilising Neutral Red (C.I. 50040), a nuclear stain, was developed to determine the cellular viability of hybridoma cells in microtitre plates. A linear correlation (r=0.99) was found to exist between the uptake of Neutral Red by viable cells and the viable cell count determined by Trypan blue exclusion test. The linearity stretched over the range of cell

K. Modha; J. P. Whiteside; R. E. Spier

1993-01-01

31

Measuring the Determinants of Relative Economic Performance of Rural Areas  

ERIC Educational Resources Information Center

|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…

Agarwal, Sheela; Rahman, Sanzidur; Errington, Andrew

2009-01-01

32

Economic determinants of IMF financial arrangements  

Microsoft Academic Search

We analyze factors that lead to IMF approval of financial arrangements. We account for both economic variables that induce a country to seek an IMF arrangement (‘demand-side’ factors) and macroeconomic policy commitments that the IMF considers when deciding whether to approve it (‘supply-side’ factors). Using a pooled sample of annual observations for 91 developing countries over 1973–1991, we obtain maximum

Malcolm Knight; Julio A. Santaella

1997-01-01

33

Cytotoxicity of T-2 toxin and its metabolites determined with the neutral red cell viability assay.  

PubMed Central

The neutral red (NR) cell viability assay was used with various cell types of human origin to quantitate the potency of T-2 mycotoxin and its metabolites. The human melanoma SK-Mel/27 cell line was the most sensitive, with a midpoint cytotoxicity value of 2.8 ng of T-2 per ml. With the human hepatoma cell line, HepG2, the sequence of potency for a series of mycotoxins was T-2 greater than HT-2 greater than T-2 triol greater than T-2 tetraol.

Babich, H; Borenfreund, E

1991-01-01

34

Quality of Financial Reporting Choice: Determinants and Economic Consequences  

Microsoft Academic Search

I investigate the determinants and economic consequences associated with firms financial reporting choices. Recognizing the endogeneity associated with these choices, Ifind evidence of a positive association between investors demands for firm-specificinformation and financial reporting quality. I also find that higher proprietary costs areassociated with a lower quality of financial information. As for the economic consequences, the evidence suggests that firms

Daniel A. Cohen

2003-01-01

35

Integrating SocioEconomic Determinants of Canadian Women's Health  

Microsoft Academic Search

HEALTH ISSUE: The association between a number of socio-economic determinants and health has been amply demonstrated in Canada and elsewhere. Over the past decades, women's increased labour force participation and changing family structure, among other changes in the socio-economic environment, have altered social roles considerably and lead one to expect that the pattern of disparities in health among women and

Bilkis Vissandjee; Marie Desmeules; Zheynuan Cao; Shelly Abdool

2004-01-01

36

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

PubMed

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. PMID:23410926

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

2013-01-07

37

Rational Economic-Social Planning Based on Needs Determination.  

National Technical Information Service (NTIS)

A project was initiated by the Department of Human Resources in Long Beach, Calif., to guide the development of the city's human resource plan. The project was titled Rational Economic - Social Planning based on Needs Determination (RESPOND). A problem - ...

P. Pflaum P. Levine M. McClelland M. McDonald S. Weinberger

1978-01-01

38

Economic determinants of emerging stock market interdependence  

Microsoft Academic Search

There is a wealth of literature on how integrated stock markets are, but very few studies attempts to determine why stock markets are integrated. However, it is arguably even more important to understand the driving forces behind stock market relationships than to know whether they exist. Such an understanding will provide a better grasp of the functioning of the global

Elna Pretorius

39

Economic determinants of emerging stock market interdependence  

Microsoft Academic Search

There is a wealth of literature on how integrated stock markets are, but very few studies attempts to determine why stock markets are integrated. However, it is arguably even more important to understand the driving forces behind stock market relationships than to know whether they exist. Such an understanding will provide a better grasp of the functioning of the global

Elna Pretorius

2002-01-01

40

Electrical determination of viability in saline-treated mouse myeloma cells  

SciTech Connect

Suspension of mouse myeloma cells in phosphate buffered saline (PBS) induced a significant amount of cell death. The lethal effects of PBS include an increase in cell lysis, a decreased ability of cells to exclude trypan blue, and a decrease in the colony-forming ability of these cells. Dead cells were also detected on a Coulter counter by the increase in the fraction of cells with a smaller electrical size distribution (ESD). Comparing mixtures of live and dead cells by ESD and trypan-blue exclusion showed a high correlation of electrical size with viability (correlation coefficient = 0.98). Sizing of PBS-treated cells by light microscopy suggested that the altered ESD of the PBS-treated cells was due to a downward shift in the volume distribution. Light-scattering experiments also suggested a decrease in the size of cells after PBS treatment. An increase in permeability of the cell membrane may also contribute to these results. We conclude that electrical sizing is an excellent indicator of physical changes that result from PBS-induced cell death, and is an effective method for distinguishing live and dead mouse myeloma cells after PBS treatment.

Matsushita, T.; Brendzel, A.M.; Shotola, M.A.; Groh, K.R.

1982-07-01

41

Electrical determination of viability in saline-treated mouse myeloma cells.  

PubMed Central

Suspension of mouse myeloma cells in phosphate buffered saline (PBS) induced a significant amount of cell death. The lethal effects of PBS include an increase in cell lysis, a decreased ability of cells to exclude trypan blue, and a decrease in the colony-forming ability of these cells. Dead cells were also detected on a Coulter counter by the increase in the fraction of cells with a smaller electrical size distribution (ESD). Comparing mixtures of live and dead cells by ESD and trypan-blue exclusion showed a high correlation of electrical size with viability (correlation coefficient = 0.98). Sizing of PBS-treated cells by light microscopy suggested that the altered ESD of the PBS-treated cells was due to a downward shift in the volume distribution. Light-scattering experiments also suggested a decrease in the size of cells after PBS treatment. An increase in permeability of the cell membrane may also contribute to these results. We conclude that electrical sizing is an excellent indicator of physical changes that result from PBS-induced cell death, and is an effective method for distinguishing live and dead mouse myeloma cells after PBS treatment.

Matsushita, T; Brendzel, A M; Shotola, M A; Groh, K R

1982-01-01

42

Determination of viability within serotypes of a soil population of Rhizobium leguminosarum bv. trifolii.  

PubMed Central

Concern has been raised about the percentage of viable cells within soil rhizobia populations measured by the immunofluorescence direct count method. The purpose of this study was to evaluate a direct viable count technique which is based on the fact that viable bacteria in natural populations undergo cell elongation when they are exposed to a combination of substrate and the inhibitor of DNA gyrase, nalidixic acid. A soil extraction procedure was developed to recover a high proportion of soil bacteria (ca. 10(9)/g of soil) in suspensions with an optical clarity suitable for accurate microscopic enumeration. After incubation for 16 to 20 h at 27 degrees C in the presence of yeast extract (200 mg/liter) and nalidixic acid (10 mg/liter), between 65 and 74% of the bacteria in soil suspension became significantly elongated (greater than or equal to 4.2 microns). In contrast, less than or equal to 0.5% of the same population could be cultured, regardless of the medium composition, nutrient concentration, or incubation conditions. The direct viable count method was combined with immunofluorescence to compare the percent viability and kinetics of appearance of elongated cells within serotypes of a soil population of Rhizobium leguminosarum bv. trifolii. Although the majority of these organisms were viable, as observed by immunofluorescence, we obtained evidence that subpopulations within the soil rhizobia community were in different states of competence to respond to substrate. A consistently low percentage (less than or equal to 30%) of the population of serotype 23 was elongated even after 24 h of incubation and regardless of when the soil was sampled.(ABSTRACT TRUNCATED AT 250 WORDS)

Bottomley, P J; Maggard, S P

1990-01-01

43

The Evolution of Citizenship: Economic and Institutional Determinants  

Microsoft Academic Search

We investigate the evolution of the legal institution of citizenship from a political economy perspective. We first present a median-voter model of the determination of citizenship laws. Next we test the implications of the model on a new set of data on citizenship laws across countries. We show that citizenship laws respond to economic and institutional determinants endogenously. When facing

Graziella Bertocchi; Chiara Strozzi

2010-01-01

44

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

PubMed

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. PMID:23524327

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

2013-03-22

45

Osmotic properties of stallion sperm subpopulations determined by simultaneous assessment of cell volume and viability.  

PubMed

The aim of this study was to determine the osmotic tolerance limits of stallion sperm as well as the osmotic behavior of different sperm subpopulations, including viable and non-viable cells as well as viable cells of different average sizes. A flow cytometric approach was used for simultaneous assessment of cell volume and permeability of the plasma membrane for the fluorescent dye propidium iodide while exposing the cells to media with different solute concentrations. Equine spermatozoa have limited osmotic tolerance limits: exposure to hypotonic conditions below approximately 240 mOsm kg(-1) already results in an increase in plasma membrane damaged cells, increasing up to 50% at an osmolality of 136 mOsm kg(-1). Plasma membrane damaged stallion sperm do not show an osmotic response after 10 min incubation in hypotonic conditions, and their volume is smaller as compared to viable cells. It is shown that inclusion or exclusion of different subpopulations greatly affects Boyle van 't Hoff behavior and therewith determination of the osmotic inactive volume. Osmotic inactive volumes were determined to be 76% and 46% of the isotonic volume for the whole sperm population and the plasma membrane intact viable cells, respectively. In addition, viable subpopulations with different average cell volumes also show different osmotic behavior. The main subpopulation of viable cells increased up to 1.6 times its isotonic volume upon exposure to 150 mOsm kg(-1), and exhibited an osmotic inactive volume of 79%. PMID:21497391

Oldenhof, Harriëtte; Blässe, Anne-Kathrin; Wolkers, Willem F; Bollwein, Heinrich; Sieme, Harald

2011-04-15

46

SPECT imaging for detecting coronary artery disease and determining prognosis by noninvasive assessment of myocardial perfusion and myocardial viability.  

PubMed

Basic knowledge of active and passive transport mechanisms for concentrating monovalent cations in myocardial cells led to the investigation of the application of radioisotopes of potassium, thallium, rubidium, and ammonia to the in vivo noninvasive assessment of regional myocardial perfusion and viability utilizing gamma camera or positron emission tomographic (PET) imaging technology. Subsequently, technetium-99m (Tc-99m)-labeled isonitriles (sestamibi and tetrofosmin), which bind to mitochondrial membranes, emerged as superior imaging agents with single photon emission tomography (SPECT) imaging. When any of these imaging agents are injected intravenously during either exercise or pharmacologic stress, myocardial defects in tracer uptake represent either abnormal regional flow reserve or myocardial scar reflecting of coronary artery disease (CAD). The major clinical indications for stress SPECT or PET myocardial perfusion imaging are for detection of CAD as the cause of chest pain and risk stratification for prognostication. Patients with normal stress myocardial perfusion scans have an excellent prognosis with <1.0% annual rate future annual death or nonfatal infarction. The greater the extent and severity of ischemic perfusion defects (defects seen on stress images but improve on resting images), the greater the subsequent death or infarction rate during follow-up. Rest imaging alone is performed for determination of myocardial viability in patients with CAD and severe left ventricular dysfunction. Myocardial segments showing >50% uptake compared to normal uptake have a better long-term outcome with revascularization than with medical therapy with enhanced left ventricular function and improved survival. Other applications of SPECT imaging include the evaluation of cardiac sympathetic function, assessment of myocardial metabolism in health and disease, and molecular imaging of coronary atherosclerosis and myocardial stem cell therapy. PMID:21732226

Beller, George A; Heede, Ruth C

2011-07-06

47

Far-red fluorescence gene reporter tomography for determination of placement and viability of cell-based gene therapies.  

PubMed

Non-invasive injectable cellular therapeutic strategies based on sustained delivery of physiological levels of BMP-2 for spinal fusion are emerging as promising alternatives, which could provide sufficient fusion without the associated surgical risks. However, these injectable therapies are dependent on bone formation occurring only at the specific target region. In this study, we developed and deployed fluorescence gene reporter tomography (FGRT) to provide information on in vivo cell localization and viability. This information is sought to confirm the ideal placement of the materials with respect to the area where early bone reaction is required, ultimately providing three dimensional data about the future fusion. However, because almost all conventional fluorescence gene reporters require visible excitation wavelengths, current in vivo imaging of fluorescent proteins is limited by high tissue absorption and confounding autofluorescence. We previously administered fibroblasts engineered to produce BMP-2, but is difficult to determine 3-D information of placement prior to bone formation. Herein we used the far-red fluorescence gene reporter, IFP1.4 to report the position and viability of fibroblasts and developed 3-D tomography to provide placement information. A custom small animal, far-red fluorescence tomography system integrated into a commercial CT scanner was used to assess IFP1.4 fluorescence and to demark 3-D placement of encapsulated fibroblasts with respect to the vertebrae and early bone formation as assessed from CT. The results from three experiments showed that the placement of the materials within the spine could be detected. This work shows that in vivo fluorescence gene reporter tomography of cell-based gene therapy is feasible and could help guide cell-based therapies in preclinical models. PMID:24104323

Lu, Yujie; Darne, Chinmay D; Tan, I-Chih; Zhu, Banghe; Hall, Mary A; Lazard, Zawaunyka W; Davis, Alan R; Simpson, Lashan; Sevick-Muraca, Eva M; Olmsted-Davis, Elizabeth A

2013-10-01

48

Models for Determining the Economic Value of Cable Television Systems  

Microsoft Academic Search

Five profit-based valuation models are estimated from a recent group of announced cable system sales. The regression-based models identify determinants of cable systems' economic value, provide elasticities, and explain over 99% of the variation in value for a sample that reflects the industry trend of consolidation. System appraisers can use both the model coefficients as well as the method to

Ian Miller

1997-01-01

49

Determinants of Grades in Maths for Students in Economics  

ERIC Educational Resources Information Center

|This paper investigates the determinants of grades achieved in maths by first-year students in economics. We use individual administrative data from 1993 to 2005 to fit an educational production function. Our main findings suggest that good secondary school achievements and the type of school attended are significantly associated with maths…

Cappellari, Lorenzo; Lucifora, Claudio; Pozzoli, Dario

2012-01-01

50

Determinants of Grades in Maths for Students in Economics  

Microsoft Academic Search

This paper investigates the determinants of grades achieved in mathematics by rst-year students in Economics. We use individual administrative data from 1993 to 2005 to t an educational production function. Our main ndings suggest that good secondary school achievements and the type of school attended are signi cantly associated with maths grades. Ceteris paribus, females typically do better than males.

Lorenzo Cappellari; Claudio Lucifora; Dario Pozzoli

2009-01-01

51

An economic model for determining AGV fleet size  

Microsoft Academic Search

One of the important issues in the design of an automated guided vehicles system (AGVS) is the determination of the number of vehicles needed to operate the system in an efficient and economical way. In this paper a multi-criteria optimization model is developed using two goals, cost and throughput performance. By using a trade-off ratio between the goals the number

D. SINRIECH; J. M. A. TANCHOCO

1992-01-01

52

Determinants of grades in maths for students in economics  

Microsoft Academic Search

This paper investigates the determinants of grades achieved in maths by first?year students in economics. We use individual administrative data from 1993 to 2005 to fit an educational production function. Our main findings suggest that good secondary school achievements and the type of school attended are significantly associated with maths grades. Ceteris paribus, females typically do better than males. Since

Lorenzo Cappellari; Claudio Lucifora; Dario Pozzoli

2010-01-01

53

Determinants of emerging market bond spread : do economic fundamentals matter?  

Microsoft Academic Search

In the 1990s international bond issues from developing countries surged dramatically, becoming one of the fastest-growing devices for financing external development. Their terms have improved as institutional investors have become more interested in emerging market securities and better economic prospects in a number of developing countries. But little is known about what determines the pricing and thus the yield spreads

Hong G. Min

1998-01-01

54

Determinants of economic growth : a bayesian panel data approach  

Microsoft Academic Search

Model uncertainty hampers consensus on the key determinants of economic growth. Some recent cross-country, cross-sectional analyses have employed Bayesian Model Averaging to address the issue of model uncertainty. This paper extends that approach to panel data models with country-specific fixed effects. The empirical results show that the most robust growth determinants are the price of investment goods, distance to major

Enrique Moral-Benito

2009-01-01

55

RAPID COMMUNICATION: A combined travelling wave dielectrophoresis and electrorotation device: applied to the concentration and viability determination of Cryptosporidium  

NASA Astrophysics Data System (ADS)

We describe a microelectrode device, fabricated using photolithography and laser ablation, that combines the electrokinetic effects of travelling wave dielectrophoresis and electrorotation. Here it has been used to concentrate and then assay the viability of Cryptosporidium parvum oocysts.

Goater, Andrew D.; Burt, Julian P. H.; Pethig, Ronald

1997-09-01

56

Determinants of grades in maths for students in economics  

Microsoft Academic Search

This paper investigates the determinants of grades achieved in maths by first-year students in economics. We use individual administrative data from 1993 to 2005 to fit an educational production function. Our main findings suggest that good secondary school achievements and the type of school attended are significantly associated with maths grades. Ceteris paribus<\\/italic>, females typically do better than males. Since

Lorenzo Cappellari; Claudio Lucifora; Dario Pozzoli

2011-01-01

57

The economic determinants of land degradation in developing countries  

PubMed Central

The following paper investigates the economic determinants of land degradation in developing countries. The main trends examined are rural households' decisions to degrade as opposed to conserve land resources, and the expansion of frontier agricultural activity that contributes to forest and marginal land conversion. These two phenomena appear often to be linked. In many developing areas, a poor rural household's decision whether to undertake long-term investment in improving existing agricultural land must be weighed against the decision to abandon this land and migrate to environmentally fragile areas. Economic factors play a critical role in determining these relationships. Poverty, imperfect capital markets and insecure land tenure may reinforce the tendency towards short-term time horizons in production decisions, and may bias land use decisions against long-term land management strategies. In periods of commodity booms and land speculation, wealthier households generally take advantage of their superior political and market power to ensure initial access to better quality resources, in order to capture a larger share of the resource rents. Poorer households are confined either to marginal environmental areas where resource rents are limited, or only have access to resources once they are degraded and rents dissipated.
Overall trends in land degradation and deforestation are examined, followed by an overview of rural households' resource management decisions with respect to land management, frontier agricultural expansion, and migration from existing agricultural land to frontiers. Finally, the discussion focuses on the scope for policy improvements to reduce economic constraints to effective land management.

Barbier, E. B.

1997-01-01

58

Cell Size and Water Permeability as Determining Factors for Cell Viability after Freezing at Different Cooling Rates  

PubMed Central

This work studied the viabilities of five types of cells (two yeast cells, Saccharomyces cerevisiae CBS 1171 and Candida utilis; two bacterial strains, Escherichia coli and Lactobacillus plantarum; and one human leukemia K562 cell) as a function of cooling rate during freezing. The range of investigated cooling rates extended from 5 to 30,000°C/min. Cell viability was classified into three ranges: (i) high viability for low cooling rates (5 to 180°C/min), which allow cell water outflow to occur completely and do not allow any intracellular crystallization; (ii) low viability for rapid cooling rates (180 to 5,000°C/min), which allow the heat flow to prevail over water outflow (in this case, cell water crystallization would occur as water was flowing out of the cell); (iii) high viability for very high cooling rates (>5,000°C/min), which allow the heat flow to be very rapid and induce intracellular crystallization and/or vitrification before any water outflow from the cell. Finally, an assumption relating cell death to the cell water crystallization as water is flowing out of the cell is made. In addition, this general cell behavior is different for each type of cell and seems to be moderated by the cell size, the water permeability properties, and the presence of a cell wall.

Dumont, Frederic; Marechal, Pierre-Andre; Gervais, Patrick

2004-01-01

59

NEW METHOD TO DETERMINE 'GIARDIA' CYST VIABILITY: CORRELATION OF FLUORESCEIN DIACETATE AND PROPIDIUM IODIDE STAINING WITH ANIMAL INFECTIVITY  

EPA Science Inventory

The viability of Giardia muris cysts was studied using the fluorogenic dyes, fluorescein diacetate (FDA) and propidium iodide (PI). Using the mouse model for giardiasis, FDA or PI stained cysts were inoculated into neonatal mice. Feces were examined at days 3, 5, 8, and 11 post-i...

60

The social and economic context and determinants of schistosomiasis japonica.  

PubMed

A variety of biological and social factors govern schistosomiasis japonica in China. Social factors include those at a national and regional level, such as policies and patterns of development, which impact on local economic activities, and affect community, household and personal risk factors of infection. Drawing on research conducted in China, we illustrate how social structural and related factors influence individual risk and prevalence of infection. At a macro-level, political changes have occurred resulting in the shift from collective to family-based production, leading to clustering of infection in families. Industrialization and urbanization, and associated increased population mobility, have also influenced patterns of transmission and infection. Types of activities and local production patterns determine the exposure of individuals to schistosome-infested water sources. Fishermen have the most frequent water contact, aquatic workers the second and farmers the third; the relative risk of Schistosoma japonicum infection follows the same order. Among farmers, human infection is significantly related to agricultural production in rice fields infested with the intermediate host snail, and to rates of the infection in livestock. Risk of S. japonicum infection is also influenced by the domestic environment, including both the location of the house in relation to snail-colonized water sources, access to safe water, and improved sanitation. Household wealth and income determine family ability to provide and maintain safe water and sanitation, while determining or interacting with other variables. At an individual level, sex, age, educational level and ethnicity are all associated with different patterns of water use and water contact behaviour thereby affecting infection rates. Schistosomiasis impairs the growth and nutrition of children and the physical work capacity of adults, and so affects economic development. Given this, we note the importance of further research and social and contextual aspects of schistosomiasis infection in order to develop and sustain sound control strategies. PMID:16202596

Huang, Yi-Xin; Manderson, Lenore

2005-10-03

61

SPECT Imaging for Detecting Coronary Artery Disease and Determining Prognosis by Noninvasive Assessment of Myocardial Perfusion and Myocardial Viability  

Microsoft Academic Search

Basic knowledge of active and passive transport mechanisms for concentrating monovalent cations in myocardial cells led to\\u000a the investigation of the application of radioisotopes of potassium, thallium, rubidium, and ammonia to the in vivo noninvasive\\u000a assessment of regional myocardial perfusion and viability utilizing gamma camera or positron emission tomographic (PET) imaging\\u000a technology. Subsequently, technetium-99m (Tc-99m)-labeled isonitriles (sestamibi and tetrofosmin), which

George A. Beller; Ruth C. Heede

2011-01-01

62

Determination of water-soluble vitamins using a colorimetric microbial viability assay based on the reduction of water-soluble tetrazolium salts  

Microsoft Academic Search

A method for the determination of water-soluble vitamins using a colorimetric microbial viability assay based on the reduction of the tetrazolium salt {2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt (WST-8)} via 2-methyl-1,4-napthoquinone (NQ) was developed. Measurement conditions were optimized for the microbiological determination of water-soluble vitamins, such as vitamin B6, biotin, folic acid, niacin, and pantothenic acid, using microorganisms that have a water-soluble vitamin

Tadayuki Tsukatani; Hikaru Suenaga; Munetaka Ishiyama; Takatoshi Ezoe; Kiyoshi Matsumoto

2011-01-01

63

Myocardial viability.  

PubMed Central

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 myocardial stunning in which function is expected to recover spontaneously. Because combinations of all of these disorders may occur, even in the same segments, caution should be used in interpreting the imaging results.

Birnbaum, Y; Kloner, R A

1996-01-01

64

The Political and Economic Determinants of Hunger in Latin America  

Microsoft Academic Search

Hunger remains a problem in much of Latin America. This paper brings together work on hunger in economics and work on the welfare state in political science to see if politics helps predict hunger better than economics alone. I hypothesize that inequality and poverty will correlate with higher levels of hunger and democracy and left government will correlate with lower

Russell Bither-Terry

65

Using Economics to Determine the Efficient Curtailment of Wind Energy  

SciTech Connect

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.

Ela, E.

2009-02-01

66

Investigating the Determinants of Relative Economic Performance for Irish Towns: A Finite Mixture Modelling Approach  

Microsoft Academic Search

Cullinan J., Garvey E. and Keane M. Investigating the determinants of relative economic performance for Irish towns: a finite-mixture modelling approach, Regional Studies. This paper uses a finite-mixture modelling approach to investigate the likely determinants of relative economic performance for Irish towns. The main argument put forward is that determinants of success can act in different ways for different groups

John Cullinan; Eoghan Garvey; Micheal Keane

2011-01-01

67

Mycobacterium avium subsp. paratuberculosis viability determination using F57 quantitative PCR in combination with propidium monoazide treatment.  

PubMed

Mycobacterium avium subsp. paratuberculosis (MAP) is known to be a very slow-growing organism. The fact that cells typically need several weeks to form visible colonies severely compromises the suitability of plate counting for assessment of viable cell counts. This problem might be overcome by the application of fast molecular methods containing a viability component. We have evaluated a promising technology combining sample treatment with propidium monoazide (PMA) prior to DNA extraction for selective detection of cells with intact cell membranes with detection of sequence element F57 by quantitative PCR (F57 qPCR). Element F57 is unique for MAP and is not known to exist in any other bacterial species. Conditions of PMA treatment were optimised for MAP isolate 7082 using live and heat-killed cells and comparing different DNA extraction procedures. The subsequent successful application of the optimised protocol to four other MAP isolates of different origins suggested that the optimised protocol might be broadly applicable to different MAP strains. Furthermore, different equations were compared to use the data resulting from this technology to optimally predict the percentage of live MAP cells in mixtures containing both live and dead cells. The presented protocol holds promise to be used routinely for detecting MAP with intact cell membranes in research applications. PMID:20385417

Kralik, P; Nocker, A; Pavlik, I

2010-03-19

68

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

Code of Federal Regulations, 2013 CFR

...economic loss for claimants who suffered physical harm. 104.45 Section 104.45...economic loss for claimants who suffered physical harm. In reaching presumed determinations...economic loss for claimants who suffered physical harm (but did not die), the...

2013-07-01

69

A theorem on the determination of economic order quantity under conditions of permissible delay in payments  

Microsoft Academic Search

This article discusses the economic quantity under conditions of permissible delay in payments. First, this article shows that the total annual variable cost function is convex. Second, with convexity, a theorem is developed to determine the economic order quantity. The theorem also reveals that the economic order quantity under conditions of permissible delay in payments is generally higher than the

Kun-jen Chung

1998-01-01

70

A factor analysis of socio-economic determinants of property crimes in cities  

Microsoft Academic Search

In the past a number of studies on the economics of crime have emphasized the importance of deterrence in crime prevention while assigning lesser importance to socio-economic determinants. Others have concentrated on the role of the socio-economic variables in crime production and have utilized the multiple regression analysis which has produced ambiguous results due to the presence of strong multicollinearity

Vijay K. Mathur

1976-01-01

71

The Determinants of Economic Sanctions Success and Failure  

Microsoft Academic Search

With an inconclusive track record, questions about the future utility of sanctions continue to plague policy makers and scholars. Drawing on previous episodes, both successful and failed sanctions tell us a great deal about economic coercion, but the causes of failure have been largely understudied. In order to further understanding of the coercive influence of sanctions, the analysis presented here

Susan Hannah Allen

2005-01-01

72

Situational determinism revisited: scientific research programmes in economics twenty years on  

Microsoft Academic Search

Spiro Latsis (Latsis 1972) applied Imre Lakatos’ methodology of scientific research programmes (MSRP) to economics. In that paper he proposed a distinction between ‘situational determinism’ and alternative theory. His distinction is effective at highlighting the importance of determinism in economics, the drive of economists to create fully deterministic models, at least up to a probability distribution. But he has been

John Nightingale

1994-01-01

73

Economics and the determination of Indian reserved water rights  

SciTech Connect

Economics plays a major role in the historically controversial Indian reserved water rights in which reserved rights differ from appropriated rights because Indian reservations predate other appropriated rights of settlers and miners. Other aspects of Indian reserved rights are their magnitude and their coexistence with the land regardless of use. Court decisions relating to practicably irrigable acres (PIA) are examined in terms of quantification of water rights and ethics. The legal analysis concludes that PIA will probably continue, but needs adjustments to the criteria to make them more strict and more appropriate. 62 references. (DCK)

Brookshire, D.S. (Univ. of Wyoming, Laramie); Merrill, J.L.; Watts, G.L.

1983-10-01

74

Viability of Rhizobium bacteroids.  

PubMed Central

Bacteroids prepared from nodules of soybean and bean were tested for viability. Contrary to the prevailing view that bacteroids are nonviable, it was found that bacteroids averaged 90% viability, irrespective of Rhizobium strain, nodule age, or nodule environment.

Tsien, H C; Cain, P S; Schmidt, E L

1977-01-01

75

Economics  

Microsoft Academic Search

The twelfth edition of this classic text has built upon the success of previous editions and has been thoroughly updated and revised to give students a deeper understanding and appreciation of the core principles of Economics. Suitable for beginners, Economics is accessible but has a rigour that will stretch readers to achieve their full potential. In-depth explanations of key theoretical

Richard G. Lipsey; Gordon R. Sparks; Peter O. Steiner

1979-01-01

76

Determinants of Economic Growth Across Embedded Economies: A Transformational Analogy of Mining Population for Human Capital  

Microsoft Academic Search

Emerging evidence shows a strong correlation between institutions and economic growth, and explains the recent research shift from focus on resources and resource productivity to institutions as determinants of economic growth. The positive correlation is read by some as indication that economies with similar institutions should perform approximately the same, and by extension embedded economies should perform like their host(s).

Voxi Heinrich S. Amavilah

2004-01-01

77

The Performance of Economics Graduates over the Entire Curriculum: The Determinants of Success  

ERIC Educational Resources Information Center

|Most studies of the determinants of understanding in economics focus on performance in a single course or standardized exam. Taking advantage of a large data set available at the U.S. Naval Academy (USNA), the authors examined the performance of economics majors over an entire curriculum. They found that gender was not a significant predictor of…

Swope, Kurtis J.; Schmitt, Pamela M.

2006-01-01

78

Determining the Economic Benefits of Attending Community College. New Directions for Community Colleges, Number 104.  

ERIC Educational Resources Information Center

This volume addresses the efforts in several states, including California, Florida, North Carolina, and Washington, to determine the economic gains of community college graduates by measuring their post-college earnings. Articles include: (1) "Economic Benefits of a Community College Education: Issues of Accountability and Performance Measures"…

Sanchez, Jorge R., Ed.; Laanan, Frankie Santos, Ed.

1998-01-01

79

Economics.  

ERIC Educational Resources Information Center

|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)|

James, L. D.

1978-01-01

80

Determination of economically feasible parameters of conduits of hydroelectric stations  

Microsoft Academic Search

Conclusions 1.The optimal cross sections of tunnels (pressure and free-flow) and of steel conduits should be determined by means of exact equations for detailed design stages and by approximate equations for rough calculations.2.In the case of complex layout schemes with the presence of daily storage reservoirs it is not possible to use analytical methods of calculating the cross sections of

V. M. Adamov

1983-01-01

81

Clinical utility and economic viability of a 3T MRI in an anti-cancer centre: The experience of the centre Oscar Lambret.  

PubMed

This paper will try and describe the installation of a 3T MRI in an anti-cancer centre. Functional sequences become indispensable in the assessment of targeted treatments. It is only possible to carry out these treatments on a routine basis in acceptable examination times with 3T. The technical constraints are overcome with third generation MRI and the improvement of the spatial resolution in examination times reduced by 30 to 50% increases patient comfort. Nevertheless, the financial constraints represent a major handicap. It is not possible to obtain an economic balance with rates based on the cost and depreciation of 1.5T imagers that are half the price. PMID:22726637

Taïeb, S; Devise, V; Pouliquen, G; Rocourt, N; Faivre-Pierret, M; Brongniart, S; Peugny, P; Ceugnart, L

2012-06-20

82

Determining the environmental fate of a filamentous fungus, Trichoderma reesei, in laboratory-contained intact soil-core microcosms using competitive PCR and viability plating.  

PubMed

Trichoderma spp. are used extensively in industry and are routinely disposed of in landfill sites as spent biomass from fermentation plants. However, little is known regarding the environmental fate of this biomass. We tracked the survival of T. reesei strain QM6A#4 (a derivative of strain QM6A marked with a recombinant construct) over a 6-month period in laboratory-contained, intact soil-core microcosms incubated in a growth chamber. Survival was tested in 3 different soils and the effect of a plant rhizosphere (bush lima beans, Phaseolus limensis) was investigated. Levels and viability of the fungus were determined, respectively, by quantitative competitive polymerase chain reaction analysis of total soil DNA extracts and dilution-plating of soil on a semiselective growth medium. Whereas chemically killed QM6A#4 became undetectable within 3 d, QM6A#4 added as a live inoculum decreased approximately 4- to approximately 160-fold over the first 1-3 months and then reached a steady state. After 4 months, soil cores were subjected to a 1.5-month simulated winter period, which did not significantly affect QM6A#4 levels. Throughout the experiment, QM6A#4 remained viable. These results indicate that, following release into the environment, live T. reesei will persist in soil for at least 2 seasons. PMID:15467788

Providenti, Miguel A; Mautner, Selma I; Chaudhry, Omar; Bombardier, Manon; Scroggins, Richard; Gregorich, Edward; Smith, Myron L

2004-08-01

83

Assessing the Financial Viability of Academic Programmes  

ERIC Educational Resources Information Center

This paper reviews and examines approaches to determining the financial viability of academic programmes as a critical component of assessing a programme's overall sustainability. Key to assessing the financial viability of a programme is understanding the teaching activities required to deliver the programme and the cost of those activities. A…

Swift, Lynette

2012-01-01

84

Economics, adoption determinants, and impacts of micro-irrigation technologies: empirical results from India  

Microsoft Academic Search

Micro-irrigation technologies are promoted for various reasons in India. Despite the reported significant economic advantages,\\u000a and the concerted support of the government and NGOs, the current micro-irrigation area in India remains an insignificant\\u000a proportion of its potential. This paper analyzes: (1) the economics of alternative micro-irrigation technologies, (2) the\\u000a determinants of adoption, (3) the poverty outreach of the different micro-irrigation

R. E. Namara; R. K. Nagar; B. Upadhyay

2007-01-01

85

VIABILIDADE TÉCNICA E ECONÔMICA DA APLICAÇÃO DE ÁGUA NA CULTURA DO FEIJOEIRO COMUM ( Phaseolus vulgaris L.) Technical and economic viability of the application of water on the culture of common bean (Phaseolus vulgaris L.)  

Microsoft Academic Search

This experiment was carried out at campus II of Patos de Minas University Center (Centro Universitário de Patos de Minas (UNIPAM) in Patos de Minas, MG, during the year of 2005, with the purpose of evaluating the yield of the common bean plant, cultivar Talismã, submitted to different levels of irrigation water replacement, as well as determining the optimum economic

Márcio José de Santana; Jacinto de Assunção Carvalho; Messias José; Bastos de Andrade; Gilson Gerson Gervásio; José Carlos Braga; Eduardo Branquinho Lepri

86

DETERMINATION OF POLLEN VIABILITY AND ROLE OF HONEY BEES APIS CERANA F. IN THE POLLINATION OF SUNFLOWER CMS LINES IN ISOLATED TUNNELS  

Microsoft Academic Search

Viability of sunflower pollen was studied by planting cytoplasmic male sterile lines (CMS) of sunflower in isolated tunnels through the sealing of Apis cerana F. for 12, 36, 60, and 84 hours in their bee hives and then bees were allowed to pollinate CMS lines in isolated tunnels. Pollination was recorded in terms of seed setting of sunflower heads at

Munir Ahmad Shahzad; Muhammad Rashid

87

A viability analysis for a stock/price model  

NASA Astrophysics Data System (ADS)

We examine the conditions for the sustainability of a stock/price system based on the use of a marine renewable resource. Instead of studying the environmental and economic interactions in terms of optimal control, we focus on the viability of the system. These viability/crisis situations are defined by a set of economic state constraints. This constraints combine a guaranteed consumption and a minimum income for fishermen. Using the mathematical concept of viability kernel, we reveal that with only economics constraints we guarantee a perennial stock/price system.

Jerry, Chakib; Raissi, Nadia

2012-09-01

88

LIMITATIONS OF THE FLUORESCENT PROBE VIABILITY ASSAY  

EPA Science Inventory

Cell viability commonly is determined flow cytometrically by the carboxyfluorescein diacetate (CFDA)/propidium iodide (PI) assay. FDA is taken up by the viable cell and converted via cytoplasmic esterase-catalyzed hydrolysis to carboxyfluorescein (CF). F fluorescence intensity is...

89

Survive Then Thrive: Determining Success in the Economics Ph.D. Program  

Microsoft Academic Search

This study investigates the completion of the Ph.D. in Economics. We use ex ante information, based solely upon reviewing a set of individual applications from former doctoral students. Estimation for determining success is done by logit, multinomial logit, and generalized ordered logit. We find that students need different skills and attributes to succeed at each distinct and sequential stage of

Wayne A. Grove; Donald H. Dutkowsky; Andrew Grodner

90

SURVIVE THEN THRIVE: DETERMINANTS OF SUCCESS IN THE ECONOMICS PH.D. PROGRAM  

Microsoft Academic Search

This study investigates the completion of the Ph.D. in economics. We use ex ante information, based upon reviewing individual applications from former doctoral students. Students need different skills to succeed at each distinct stage of the doctoral program. Significant determinants for passing the comprehensive exams include Graduate Record Exam (GRE) verbal and quantitative scores, a Masters degree, and prior focus

WAYNE A. GROVE; DONALD H. DUTKOWSKY; ANDREW GRODNER

2007-01-01

91

ECONOMIC AND NONECONOMIC DETERMINANTS OF POLITICAL DEMOCRACY IN THE 1960s  

Microsoft Academic Search

Most cross-national empirical research on political democracy has focused largely on the relationship between economic development and democracy. However, a rich theoretical and substantive literature exists which suggests the importance of noneconomic determinants. In this study, we review the work of a number of scholars who suggest that cultural pluralism, Protes- tantism, and colonial experience may affect a country's chances

Kenneth A. Bollen; Robert W. Jackrnan

92

An Economic Analysis of the Determination of Interchange Fees in Payment Card Systems  

Microsoft Academic Search

The paper investigates, in a non-technical fashion, the economic determinants of interchange fees in payment card systems and the potential need for their regulation. Among other things, it demonstrates that the proposal for a cost-based regulation of interchange fees relies on an erroneous, vertically organized, model of the payment card industry.

Jean-Charles Rochet; Jean Tirole

2003-01-01

93

THE EOQ-FAS MODEL: A FUZZY ANT SYSTEM FOR DETERMINING ECONOMIC ORDER QUANTITY  

Microsoft Academic Search

This paper presents the application of an Ant System designed to facilitate decision making in stock management, specifically, the determination of economic order quantity under conditions of uncertainty and non-linearity. Thereafter, its validity and applicability is tested through a sam- ple practical experiment.

Cristina Mendaña Cuervo; Enrique López González; Belén Vaquerizo García; Dpto. Dirección

94

Economic and Technical Feasibility of Utilizing Fish Waste as Organic Nutrients for Farm/Horticultural Use. Final Report.  

National Technical Information Service (NTIS)

Results of a study to determine the technical and economic viability of utilizing fish wastes and other organic residues as organic peat nutrients for agriculture/horticulture applications are presented. The project tasks included: (1) Reputable analysis ...

R. E. Gargasz E. K. Pye

1985-01-01

95

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

SciTech Connect

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.

Annecke, W. (Energy and Development Research Center, University of Cape Town, South Africa)

1999-03-29

96

Social and institutional factors as determinants of economic growth: Evidence from the United States counties  

Microsoft Academic Search

.   In the search for explanations of persistent differences in economic growth rates, the conditional convergence growth model\\u000a has introduced the possibility of incorporating a wide set of factors as determinants of growth. Controlling for spatial dependence,\\u000a we assess the contribution of differences in social and institutional variables on growth rates of per capita income for counties\\u000a in the United

Anil Rupasingha; Stephan J. Goetz; David Freshwater

2002-01-01

97

A Review of the Literature on the Social and Economic Determinants of Parental Time  

Microsoft Academic Search

Parental time has been identified as a key determinant in the healthy development of a child. The literature on this topic\\u000a has rapidly increased in recent years and has revealed large variations in the amount of time that parents devote to their\\u000a children, including variations over time and across social and economic subgroups of the population. This paper synthesizes\\u000a research

Berenice Monna; Anne H. Gauthier

2008-01-01

98

Using Panel Data to Estimate the Economic Determinants of CEO Compensation  

Microsoft Academic Search

The present study uses the latest data available from ExecuComp in order to estimate an economic model of the determinants of CEO compensation. Examining 975 CEO’s over the period 1992-2002, the present study finds that experience had a positive effect on CEO pay, while industry specific dummy variables had little, if any, effect on compensation. Performance measures, such as net

Mark Gius

2007-01-01

99

Investigating socio-economic-demographic determinants of tobacco use in Rawalpindi, Pakistan  

Microsoft Academic Search

BACKGROUND: To investigate the socio-economic and demographic determinants of tobacco use in Rawalpindi, Pakistan. METHODS: Cross sectional survey of households (population based) with 2018 respondent (1038 Rural; 980 Urban) was carried out in Rawalpindi (Pakistan) and included males and females 18–65 years of age. Main outcome measure was self reported daily tobacco use. RESULTS: Overall 16.5% of the study population

Ali Yawar Alam; Azhar Iqbal; Khalif Bile Mohamud; Ronald E Laporte; Ashfaq Ahmed; Sania Nishtar

2008-01-01

100

Myocardial viability assessed by dobutamine stress echocardiography predicts reduced mortality early after acute myocardial infarction: determining the risk of events after myocardial infarction (DREAM) study  

PubMed Central

Objective To establish further the role of dobutamine stress echocardiography (DSE) in prognostication of outcome early after acute myocardial infarction (AMI) Methods Consecutive patients presenting with AMI were screened for inclusion into the study. 212 stable consenting patients underwent DSE a mean (SD) of 4.8 (1.5) days after AMI. Patients were then followed up for 803 (297) days. Results The mean (SD) resting systolic wall thickening index (SWTI) was 1.6 (0.4), 44% patients had evidence of viability at low dose, and 38% had evidence of ischaemia. During the follow up period 27 (13%) patients died and 16 (8%) had a non?fatal AMI. Independent predictors of both mortality and combined mortality and non?fatal AMI were age (hazard ratio (HR) 1.04/year, p??=??0.01, and HR 1.03/year, p??=??0.04, respectively) and SWTI at low dose (HR 3.6, p?viability has a positive impact on survival.

Swinburn, J M A; Senior, R

2006-01-01

101

Positron Emission Tomography for the Assessment of Myocardial Viability  

PubMed Central

Executive Summary In July 2009, the Medical Advisory Secretariat (MAS) began work on Non-Invasive Cardiac Imaging Technologies for the Assessment of Myocardial Viability, an evidence-based review of the literature surrounding different cardiac imaging modalities to ensure that appropriate technologies are accessed by patients undergoing viability assessment. This project came about when the Health Services Branch at the Ministry of Health and Long-Term Care asked MAS to provide an evidentiary platform on effectiveness and cost-effectiveness of non-invasive cardiac imaging modalities. After an initial review of the strategy and consultation with experts, MAS identified five key non-invasive cardiac imaging technologies that can be used for the assessment of myocardial viability: positron emission tomography, cardiac magnetic resonance imaging, dobutamine echocardiography, and dobutamine echocardiography with contrast, and single photon emission computed tomography. A 2005 review conducted by MAS determined that positron emission tomography was more sensitivity than dobutamine echocardiography and single photon emission tomography and dominated the other imaging modalities from a cost-effective standpoint. However, there was inadequate evidence to compare positron emission tomography and cardiac magnetic resonance imaging. Thus, this report focuses on this comparison only. For both technologies, an economic analysis was also completed. The Non-Invasive Cardiac Imaging Technologies for the Assessment of Myocardial Viability is made up of the following reports, which can be publicly accessed at the MAS website at: www.health.gov.on.ca/mas or at www.health.gov.on.ca/english/providers/program/mas/mas_about.html Positron Emission Tomography for the Assessment of Myocardial Viability: An Evidence-Based Analysis Magnetic Resonance Imaging for the Assessment of Myocardial Viability: An Evidence-Based Analysis Objective The objective of this analysis is to assess the effectiveness and safety of positron emission tomography (PET) imaging using F-18-fluorodeoxyglucose (FDG) for the assessment of myocardial viability. To evaluate the effectiveness of FDG PET viability imaging, the following outcomes are examined: the diagnostic accuracy of FDG PET for predicting functional recovery; the impact of PET viability imaging on prognosis (mortality and other patient outcomes); and the contribution of PET viability imaging to treatment decision making and subsequent patient outcomes. Clinical Need: Condition and Target Population Left Ventricular Systolic Dysfunction and Heart Failure Heart failure is a complex syndrome characterized by the heart’s inability to maintain adequate blood circulation through the body leading to multiorgan abnormalities and, eventually, death. Patients with heart failure experience poor functional capacity, decreased quality of life, and increased risk of morbidity and mortality. In 2005, more than 71,000 Canadians died from cardiovascular disease, of which, 54% were due to ischemic heart disease. Left ventricular (LV) systolic dysfunction due to coronary artery disease (CAD)1 is the primary cause of heart failure accounting for more than 70% of cases. The prevalence of heart failure was estimated at one percent of the Canadian population in 1989. Since then, the increase in the older population has undoubtedly resulted in a substantial increase in cases. Heart failure is associated with a poor prognosis: one-year mortality rates were 32.9% and 31.1% for men and women, respectively in Ontario between 1996 and 1997. Treatment Options In general, there are three options for the treatment of heart failure: medical treatment, heart transplantation, and revascularization for those with CAD as the underlying cause. Concerning medical treatment, despite recent advances, mortality remains high among treated patients, while, heart transplantation is affected by the limited availability of donor hearts and consequently has long waiting lists. The third option, revascularization, is used to restore the flow of blood t

2010-01-01

102

Pathways of neighbourhood-level socio-economic determinants of adverse birth outcomes  

PubMed Central

Background Although socio-economic factors have been identified as one of the most important groups of neighbourhood-level risks affecting birth outcomes, uncertainties still exist concerning the pathways through which they are transferred to individual risk factors. This poses a challenge for setting priorities and developing appropriate community-oriented public health interventions and planning guidelines to reduce the level of adverse birth outcomes. Method This study examines potential direct and mediated pathways through which neighbourhood-level socio-economic determinants exert their impacts on adverse birth outcomes. Two hypothesized models, namely the materialist and psycho-social models, and their corresponding pathways are tested using a binary-outcome multilevel mediation analysis. Live birth data, including adverse birth outcomes and person-level exposure variables, were obtained from three public health units in the province of Ontario, Canada. Corresponding neighbourhood-level socio-economic, psycho-social and living condition variables were extracted or constructed from the 2001 Canadian Census and the first three cycles (2001, 2003, and 2005) of the Canadian Community Health Surveys. Results Neighbourhood-level socio-economic-related risks are found to have direct effects on low birth weight and preterm birth. In addition, 20-30% of the total effects are contributed by indirect effects mediated through person-level risks. There is evidence of four person-level pathways, namely through individual socio-economic status, psycho-social stress, maternal health, and health behaviours, with all being simultaneously at work. Psycho-social pathways and buffering social capital-related variables are found to have more impact on low birth weight than on preterm birth. Conclusion The evidence supports both the materialist and psycho-social conceptualizations and the pathways that describe them, although the magnitude of the former is greater than the latter.

2013-01-01

103

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

PubMed Central

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.

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

2013-01-01

104

Nutritional status of children in India: household socio-economic condition as the contextual determinant  

PubMed Central

Background Despite recent achievement in economic progress in India, the fruit of development has failed to secure a better nutritional status among all children of the country. Growing evidence suggest there exists a socio-economic gradient of childhood malnutrition in India. The present paper is an attempt to measure the extent of socio-economic inequality in chronic childhood malnutrition across major states of India and to realize the role of household socio-economic status (SES) as the contextual determinant of nutritional status of children. Methods Using National Family Health Survey-3 data, an attempt is made to estimate socio-economic inequality in childhood stunting at the state level through Concentration Index (CI). Multi-level models; random-coefficient and random-slope are employed to study the impact of SES on long-term nutritional status among children, keeping in view the hierarchical nature of data. Main findings Across the states, a disproportionate burden of stunting is observed among the children from poor SES, more so in urban areas. The state having lower prevalence of chronic childhood malnutrition shows much higher burden among the poor. Though a negative correlation (r = -0.603, p < .001) is established between Net State Domestic Product (NSDP) and CI values for stunting; the development indicator is not always linearly correlated with intra-state inequality in malnutrition prevalence. Results from multi-level models however show children from highest SES quintile posses 50 percent better nutritional status than those from the poorest quintile. Conclusion In spite of the declining trend of chronic childhood malnutrition in India, the concerns remain for its disproportionate burden on the poor. The socio-economic gradient of long-term nutritional status among children needs special focus, more so in the states where chronic malnutrition among children apparently demonstrates a lower prevalence. The paper calls for state specific policies which are designed and implemented on a priority basis, keeping in view the nature of inequality in childhood malnutrition in the country and its differential characteristics across the states.

2010-01-01

105

Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of C02 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales  

Microsoft Academic Search

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

Michael F. Morea

1998-01-01

106

Advanced reservoir characterization in the antelope shale to establish the viability of COâ enhanced oil recovery in California`s Monterey formation siliceous shales. Technical progress report  

Microsoft Academic Search

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 COâ enhanced oil recovery project in the Buena Vista Hills field. The Buena Vista Hills pilot COâ project will demonstrate the economic viability and widespread applicability of

1996-01-01

107

Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of C02 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales  

Microsoft Academic Search

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

Michael F. Morea

1997-01-01

108

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

Microsoft Academic Search

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

Morea; Michael F

1999-01-01

109

Magnetic Resonance Imaging (MRI) for the Assessment of Myocardial Viability  

PubMed Central

Executive Summary In July 2009, the Medical Advisory Secretariat (MAS) began work on Non-Invasive Cardiac Imaging Technologies for the Assessment of Myocardial Viability, an evidence-based review of the literature surrounding different cardiac imaging modalities to ensure that appropriate technologies are accessed by patients undergoing viability assessment. This project came about when the Health Services Branch at the Ministry of Health and Long-Term Care asked MAS to provide an evidentiary platform on effectiveness and cost-effectiveness of noninvasive cardiac imaging modalities. After an initial review of the strategy and consultation with experts, MAS identified five key non-invasive cardiac imaging technologies that can be used for the assessment of myocardial viability: positron emission tomography, cardiac magnetic resonance imaging, dobutamine echocardiography, and dobutamine echocardiography with contrast, and single photon emission computed tomography. A 2005 review conducted by MAS determined that positron emission tomography was more sensitivity than dobutamine echocardiography and single photon emission tomography and dominated the other imaging modalities from a cost-effective standpoint. However, there was inadequate evidence to compare positron emission tomography and cardiac magnetic resonance imaging. Thus, this report focuses on this comparison only. For both technologies, an economic analysis was also completed. A summary decision analytic model was then developed to encapsulate the data from each of these reports (available on the OHTAC and MAS website). The Non-Invasive Cardiac Imaging Technologies for the Assessment of Myocardial Viability is made up of the following reports, which can be publicly accessed at the MAS website at: www.health.gov.on.ca/mas or at www.health.gov.on.ca/english/providers/program/mas/mas_about.html Positron Emission Tomography for the Assessment of Myocardial Viability: An Evidence-Based Analysis Magnetic Resonance Imaging for the Assessment of Myocardial Viability: An Evidence-Based Analysis Objective The objective of this analysis is to assess the effectiveness and cost-effectiveness of cardiovascular magnetic resonance imaging (cardiac MRI) for the assessment of myocardial viability. To evaluate the effectiveness of cardiac MRI viability imaging, the following outcomes were examined: the diagnostic accuracy in predicting functional recovery and the impact of cardiac MRI viability imaging on prognosis (mortality and other patient outcomes). Clinical Need: Condition and Target Population Left Ventricular Systolic Dysfunction and Heart Failure Heart failure is a complex syndrome characterized by the heart’s inability to maintain adequate blood circulation through the body leading to multiorgan abnormalities and, eventually, death. Patients with heart failure experience poor functional capacity, decreased quality of life, and increased risk of morbidity and mortality. In 2005, more than 71,000 Canadians died from cardiovascular disease, of which, 54% were due to ischemic heart disease. Left ventricular (LV) systolic dysfunction due to coronary artery disease (CAD) 1 is the primary cause of heart failure accounting for more than 70% of cases. The prevalence of heart failure was estimated at one percent of the Canadian population in 1989. Since then, the increase in the older population has undoubtedly resulted in a substantial increase in cases. Heart failure is associated with a poor prognosis: one-year mortality rates were 32.9% and 31.1% for men and women, respectively in Ontario between 1996 and 1997. Treatment Options In general, there are three options for the treatment of heart failure: medical treatment, heart transplantation, and revascularization for those with CAD as the underlying cause. Concerning medical treatment, despite recent advances, mortality remains high among treated patients, while, heart transplantation is affected by the limited availability of donor hearts and consequently has long waiting lists. The third option, revascularization, is used

2010-01-01

110

Review article Molecular methods for the assessment of bacterial viability  

Microsoft Academic Search

A significant number of pathogenic microorganisms can be found in environmental reservoirs (air, water, soil). It is important to assess the viability status of these organisms to determine whether they pose a threat to public health. Classical methods for determining viability are time consuming. Hence, molecular methods have been developed to address this problem. Molecular methods offer speed, sensitivity and

J. T. Keer; L. Birch

111

Agriculture and Rural Viability.  

ERIC Educational Resources Information Center

|Agriculture and the rural economic bases in mining, fisheries, forestry, and natural resource extraction are experiencing major social and economic changes. The farm and rural crises of the 1980s are not short-term aberrations, but symptoms of long-term trends that were partially hidden by the relatively good times for agriculture and rural areas…

North Carolina State Univ., Raleigh. Agricultural Experiment Station.

112

The socio-economic determinants of terrorism and political violence in Western Europe (1994–2007)  

Microsoft Academic Search

The main objective of this paper is to empirically investigate the socio-economic causes of terrorism and political violence in a sample of 12 countries in Western Europe. First, we show that in western European countries the classical economic argument of opportunity cost is confirmed. That is, the larger is the set of current economic opportunities for individuals the lower is

Raul Caruso; Friedrich Schneider

2011-01-01

113

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

PubMed

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. PMID:22305807

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

2012-01-21

114

Viability, Advantages and Design Methodologies of M-Learning Delivery  

ERIC Educational Resources Information Center

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…

Zabel, Todd W.

2010-01-01

115

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

PubMed Central

Executive Summary Objective The objective of this health technology policy assessment was to determine the effectiveness safety and cost-effectiveness of using functional cardiac magnetic resonance imaging (MRI) for the assessment of myocardial viability and perfusion in patients with coronary artery disease and left ventricular dysfunction. Results Functional MRI has become increasingly investigated as a noninvasive method for assessing myocardial viability and perfusion. Most patients in the published literature have mild to moderate impaired LV function. It is possible that the severity of LV dysfunction may be an important factor that can alter the diagnostic accuracy of imaging techniques. There is some evidence of comparable or better performance of functional cardiac MRI for the assessment of myocardial viability and perfusion compared with other imaging techniques. However limitations to most of the studies included: Functional cardiac MRI studies that assess myocardial viability and perfusion have had small sample sizes. Some studies assessed myocardial viability/perfusion in patients who had already undergone revascularization, or excluded patients with a prior MI (Schwitter et al., 2001). Lack of explicit detail of patient recruitment. Patients with LVEF >35%. Interstudy variability in post MI imaging time(including acute or chronic MI), when patients with a prior MI were included. Poor interobserver agreement (kappa statistic) in the interpretation of the results. Traditionally, 0.80 is considered “good”. Cardiac MRI measurement of myocardial perfusion to as an adjunct tool to help diagnose CAD (prior to a definitive coronary angiography) has also been examined in some studies, with methodological limitations, yielding comparable results. Many studies examining myocardial viability and perfusion report on the accuracy of imaging methods with limited data on long-term patient outcome and management. Kim et al. (2000) revealed that the transmural 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 better select which patients [who have CAD and severe LV dysfuncti

2003-01-01

116

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

PubMed Central

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.

Moreira, Pedro A; Padrao, Patricia D

2004-01-01

117

Area at Risk and Viability after Myocardial Ischemia and Reperfusion Can Be Determined by Contrast-Enhanced Cardiac Magnetic Resonance Imaging  

Microsoft Academic Search

Background\\/Aims: Clinical differentiation between infarcted and viable myocardium in the ischemic area at risk is controversial. We investigated the potential of contrast-enhanced cardiac magnetic resonance imaging (ceCMRI) in determining the area at risk 24 h after ischemia. Methods: Myocardial ischemia was induced by percutaneous coronary intervention of the left anterior descending coronary artery in pigs. Coronary occlusion time was 30

M. Vosseler; N. Abegunewardene; N. Hoffmann; S. E. Petersen; D. Becker; D. Cleppien; P. Kunz; K.-F. Kreitner; M. Lauterbach; B. Bierbach; C. Düber; T. Gori; T. Münzel; L. M. Schreiber; G. Horstick

2009-01-01

118

Light quality and phytoplankton viability  

Microsoft Academic Search

A method is presented, using calculations of the underwater light field, to examine viability of phytoplankton at depth. For this study, viability is defined as the ability of phytoplankton to harvest, and efficiently convert enough photons into primary production to overcome metabolic demands. How the available light field influences the production environment is examined. Changes in water column constituents, such

Lisa A Malick

2004-01-01

119

The business of palliative medicine—Part 2: The economics of acute inpatient palliative medicine  

Microsoft Academic Search

Economic feasibility is a major factor in the viability of established acute inpatient palliative medicine. Several clinical, administrative, and financial parameters determine the financial health of inpatient care. Financial management metrics include case mix index (CMI) (as determined by the Federal Register as an assigned relative weight to the diagnosis-related group (DRG) reflecting resource consumption), direct costs, indirect costs, contribution

Mellar P. Davis; Declan Walsh; Kristine A. Nelson; Dale Konrad; Susan B. LeGrand; Lisa Rybicki

2002-01-01

120

Getting More Bang for the Buck: Determining the Economic Rationale of Vocational Education. A VES Monograph.  

ERIC Educational Resources Information Center

|Vocational education in the United States has come under increased scrutiny, and its proponents need the tools to convince the critics of its merits. Many economic conditions have a strong impact on vocational education, and understanding of economics is important in offering a rationale of vocational education. In a time of shrinking revenues,…

McElhinney, Kerry R.; Pershing, James A.

121

Determinants of Human Capital Formation and Economic Growth of African Countries  

ERIC Educational Resources Information Center

|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,…

Oketch, Moses O.

2006-01-01

122

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

ERIC Educational Resources Information Center

|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…

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

2012-01-01

123

Characterization of edge radial electric field structures in the Large Helical Device and their viability for determining the location of the plasma boundary  

NASA Astrophysics Data System (ADS)

This paper provides a systematic investigation on how plasma conditions (magnetic configuration, collisionality and beta) affect the edge radial electric field (Er) structure derived from charge exchange spectroscopic measurements in the Large Helical Device. We found that the location at which the spatial derivative in the Er structure (?Er) had a local maximum value (R_{LCFS}^{CXS}) shifts outwards from the vacuum last closed flux surface location (R_{LCFS}^{VACUUM}) as the volume-averaged plasma beta (the ratio of the plasma pressure to the magnetic pressure, ? ? measured by a diamagnetic loop) becomes large. The loss of electrons on the open field lines, leaving the ions behind, might be the physics that determines the positive Er structure just outside the plasma boundary. The collisionality dependence of the experimentally observed Er values inside the plasma boundary is found to be consistent with a neoclassical ambipolar condition, while the Er formation outside the plasma boundary is different from the trend that is predicted by the neoclassical theory inside the plasma boundary. Furthermore, experimental data on saturation in the shift of the R_{LCFS}^{CXS} location even in a higher ? regime (3% ? ? ? 4.5%) are presented, inferring and predicting shrinkage of the plasma (i.e. a reduction in the averaged minor radius) in the higher ? regime in which the Shafranov shift becomes larger.

Kamiya, K.; Ida, K.; Yoshinuma, M.; Suzuki, C.; Suzuki, Y.; Yokoyama, M.; the LHD Experiment Group

2013-01-01

124

Advanced reservoir characterizstion in the Antelope Shale to establish the viability of COâ enhanced oil recovery in California`s Monterey formation siliceous shales. Quarterly report, July 1 - September 30, 1996  

Microsoft Academic Search

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 COâ enhanced oil recovery project in the Antelope Shale in Buena Vista Hills field. The Buena Vista Hills Pilot COâ project will demonstrate the economic viability and

1996-01-01

125

Advanced reservoir characterization in the Antelope Shale to establish the viability of COâ enhanced oil recovery in California`s Monterey Formation siliceous shales. Quarterly progress report, January 1March 31, 1998  

Microsoft Academic Search

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 COâ enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot COâ project will demonstrate the economic viability and

Morea

1998-01-01

126

Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of CO(2) Enhanced Oil Recovery in California`s Monterey formation Siliceous Shales. Progress report, April 1June 30, 1997  

Microsoft Academic Search

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 C0â enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills Pilot C0â project will demonstrate the economic viability and

Morea

1997-01-01

127

Advanced reservoir characterization in the Antelope Shale to establish the viability of COâ enhanced oil recovery in California`s Monterey formation siliceous shales. Quarterly report, April 1, 1997June 30, 1997  

Microsoft Academic Search

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 COâ enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot COâ project will demonstrate the economic viability and

Morea

1997-01-01

128

Advanced reservoir characterization in the Antelope Shale to establish the viability of COâ enhanced oil recovery in California`s Monterey Formation siliceous shales. Quarterly report, October 1, 1996December 31, 1996  

Microsoft Academic Search

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 COâ enhanced oil recovery project in the Antelope Shale in Buena Vista Hills field. The Buena Vista Hills pilot COâ project will demonstrate the economic viability and

Toronyi

1996-01-01

129

Advanced reservoir characterization in the Antelope Shale to establish the viability of COâ enhanced oil recovery in California`s Monterey formation siliceous shales. Quarterly report, April 1, 1996 - June 30, 1996  

Microsoft Academic Search

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 COâ enhanced oil recovery project in the Buena Vista Hills field. The Buena Vista Hills pilot COâ project will demonstrate the economic viability and widespread applicability Of

1996-01-01

130

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

PubMed Central

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.

2011-01-01

131

Trustworthiness as a Moral Determinant of Economic Activity: Lessons from the Classics  

Microsoft Academic Search

This paper reviews the way that social norms and ethical values in general, and trustworthiness in particular, is perceived\\u000a to affect the behavior of economic agents in view of the work of Adam Smith, Nassau William Senior and John Stuart Mill. Classical\\u000a Political economists held that economic actions are context-dependent and thus constantly under the influence of social norms\\u000a and

Michel S. Zouboulakis

2010-01-01

132

Viability and sunlight sensitivity of oak pollen and its implications for pollen-mediated gene flow  

Microsoft Academic Search

Pollen-mediated gene flow and the male reproductive success of wind-pollinated trees depend on the initial viability of the pollen and the changes that occur in its viability during transport in the atmosphere. The viability of Quercus robur pollen was determined before and during exposure to sunlight by in vitro germination and the fluorescein diacetate reaction (FCR) in 2002 and 2003,

Silvio Schueler; Katharina Heinke Schlünzen; Florian Scholz

2005-01-01

133

Television Economics.  

ERIC Educational Resources Information Center

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…

Owen, Bruce M.; And Others

134

Television Economics.  

ERIC Educational Resources Information Center

|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…

Owen, Bruce M.; And Others

135

Economic and technical feasibility of utilizing fish waste as organic nutrients for farm/horticultural use. Final report  

SciTech Connect

Results of a study to determine the technical and economic viability of utilizing fish wastes and other organic residues as organic peat nutrients for agriculture/horticulture applications are presented. The project tasks included: (1) Reputable analysis of the waste products to determine the primary plant nutrients, nitrogen, phosphorus, and potash as well as trace elements; (2) Technical feasibility of reducing these organic wastes into nutrients, valuable and assimilable by agricultural or horticultural crops or as a high protein animal feed; and (3) The economic viability of commercializing, manufacturing, and marketing these waste products as a specialty plant growth substance/high protein feed supplement.

Gargasz, R.E.; Pye, E.K.

1985-01-01

136

THE DETERMINANTS OF THE VIETNAMESE ECONOMICS COMPETITIVENESS, A LESSON FOR DEVELOPING COUNTRIES  

Microsoft Academic Search

Vietnam has been very successful for the last two decades, since the adoption of “Doi moi” in 1986. Over the last two decades, an economic growth rate in Vietnam has been one of the highest worldwide (with GDP growing by respectively 8% per year). The increase of the Vietnamese share of world trade is the highest of all major Asian

Van Ha NGUYEN; Xavier GALIEGUE

2011-01-01

137

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

ERIC Educational Resources Information Center

|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…

Farrell, Terence; Casavant, Ken; Jessup, Eric

2007-01-01

138

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

ERIC Educational Resources Information Center

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…

Jojola, Theodore S.; Agoyo, Herman

139

Economic Conditions as a Determinant of Political Violence in the Palestinian Territories  

Microsoft Academic Search

This paper argues against the findings of Krueger and Maleckova (2002) and that of Berrebi (2003). I provide evidence that Palestinian economic conditions are related to the level of attacks against Israelis. The results of the negative binomial regression suggest that the number of shooting attacks against Israelis will rise with the number of Palestinians killed. However, I don't find

Basel A. Saleh

140

An economic spreadsheet model to determine optimal breeding and replacement decisions for dairy cattle  

Microsoft Academic Search

The aim of this paper is to describe a user-friendly spreadsheet culling model that was constructed to support economical, optimal breeding and replacement decisions on dairy farms. The model was based on the marginal net revenue technique. Inputs for the model can be entered for specific farm conditions, and the output is easily accessible. In the model, the retention pay-off

H. Groenendaal; D. T. Galligan; H. A. Mulder

2004-01-01

141

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

ERIC Educational Resources Information Center

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…

Carvajal, Manuel J.; And Others

1993-01-01

142

Young polish consumers: Economic determinants, household equipment, skills, participation in culture  

Microsoft Academic Search

The collapse of the communist system in Poland and the rise of a new market economy increasingly oriented towards and integrated with the world economy has changed the economic expectations of the younger generation in particular. They increasingly exhibit patterns of earning and spending that are characteristic of the youth in Western countries. Surveys reveal both growing diversity in income

Bohdan Jung

1995-01-01

143

A Systematic Approach to Determine Economic Potential and Environmental Impact of Biorefineries  

Microsoft Academic Search

The integrated biorefinery has the potential to provide a strong, self-dependent alternative to the use of fossil fuels for the production of chemicals and energy, but difficulties arise in measuring the potential economic and environmental benefit of the biorefinery. A myriad of products and production pathways are possible in this growing field of biorefining, and the production path with maximum

Norman Sammons; Wei Yuan; Susilpa Bommareddy; Mario Eden; Burak Aksoy; Harry Cullinan

2009-01-01

144

The characteristics of overseas Chinese business: cultural determination or choice of economic role  

Microsoft Academic Search

People tend to attribute characteristics of Chinese business practices to the unique Chinese cultural influences. This paper will try to study the origins of overseas Chinese enterprise management style from the perspective of local economic and global surroundings. (1) The multinational enterprises can make large profits relying on their brand names and advanced technology. Overseas Chinese businesspeople, on the other

Denggao Long; Qiming Han

145

Recent Trends in the Economic Status of Boston's Aged: Determinants and Policy Implications  

Microsoft Academic Search

The economic status of the older population has improved significantly since the early 1970s. Yet poverty rates among certain groups of elderly, especially older minorities, have declined very little. To understand the reasons for these seemingly contradictory trends, changes in the income composition of the elderly in Boston are compared to changes in income for the elderly in the United

William H. Crown

1988-01-01

146

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

Microsoft Academic Search

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

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

2003-01-01

147

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

PubMed

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. PMID:12881622

Kabir, Zubair

2003-07-01

148

Physical and Economic Potential of Geological CO2 Storage in Saline Aquifers  

Microsoft Academic Search

Carbon sequestration in sandstone saline reservoirs holds great potential for mitigating climate change, but its storage potential and cost per ton of avoided CO2emissions are uncertain. We develop a general model to determine the maximum theoretical constraints on both storage potential and injection rate and use it to characterize the economic viability of geosequestration in sandstone saline aquifers. When applied

JORDAN K. E CCLES; LINCOLN P RATSON; RICHARD G. N EWELL; ROBERT B. J ACKSON

2009-01-01

149

Viability of keratocytes in epikeratophakia lenticules.  

PubMed Central

AIM: To study the influence of cryoprotectant, cooling rate, and warming rate on recovery and viability of keratocytes from corneas for cryolathing. METHODS: Corneas were frozen at -50 degrees C for 2 minutes either after exposure to 10% dimethyl sulphoxide in Eagle's MEM for 15 minutes at room temperature (about 22 degrees C), or without earlier exposure to the cryoprotectant. Corneas were cooled either rapidly (20 degrees C/min) or slowly (1 degree C/min), and they were warmed either rapidly (> 50 degrees C/min) by direct transfer into medium at 22 degrees C or slowly (< 20 degrees C/min) in air at 22 degrees C. The cryoprotectant was removed by dilution in medium containing 0.5 mol/l sucrose. Recovery of keratocytes was determined by using collagenase digestion to release the cells from the stroma and trypan blue staining. Viability was assessed by the outgrowth of cells from stromal explants in primary tissue culture. RESULTS: The use of a cryoprotectant before freezing was beneficial, irrespective of the different cooling and warming regimens. Both collagenase digestion and tissue culture revealed that keratocyte survival was improved when corneas were warmed rapidly rather than slowly. The collagenase digestion assay showed an apparently higher recovery of keratocytes after slow cooling (54.3%) than after rapid cooling (34.1%), but no differences in cell viability could be demonstrated by primary tissue culture. CONCLUSION: Although in these experiments slow cooling apparently provided the best recovery of keratocyte numbers (though not viability), previous work had revealed some disruption of the epithelial basement membrane after slow cooling. If viable keratocytes and good preservation of epithelial basement membrane are considered to be prerequisites for epikeratophakia lenticules then it is suggested that corneas should be prepared for cryolathing by freezing rapidly after exposure to 10% dimethyl sulphoxide and, following cryolathing, they should be warmed rapidly.

Cheng, H C; Armitage, W J; Yagoubi, M I; Easty, D L

1996-01-01

150

Viability of Urban Social Technologies  

Microsoft Academic Search

From the perspective of viability, we critically examine the attractiveness of urban social technologies. We discuss two inherent difficulties in design of this type of technology, namely intentional design of social activity and the need for social innovation a long side a technical innovation. Fi- nally, we touch upon the relevance of ethnographic inspired methods in the design of urban

Jens Pedersen; Anna Vallgarda

151

Pollen viability and pollen vigor  

Microsoft Academic Search

Investigations were carried out to correlate pollen viability, assessed on the basis of a fluorochromatic reaction (FCR) test, with pollen vigor, assessed on the basis of the time taken for in vitro germination in pollen grains subjected to high humidity (>95% RH) and temperature (38 °C) or storage stress of Nicotiana tabacum, Agave sp., Tradescantia virginiana, and Iris sp. Both

K. R. Shivanna; H. F. Linskens; M. Cresti

1991-01-01

152

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

PubMed

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. PMID:12665744

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

2003-04-01

153

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

Code of Federal Regulations, 2011 CFR

...2011-10-01 false What rules determine...DISADVANTAGED BUSINESS ENTERPRISES...26.67 What rules determine...disadvantage? (a) Presumption...disadvantaged owner is, in fact...notarized statement of personal...1) If the statement of personal...paragraph (a)(2) of...disadvantage is...

2011-10-01

154

The cardiac magnetic resonance (CMR) approach to assessing myocardial viability  

PubMed Central

Cardiac magnetic resonance (CMR) is a noninvasive imaging method that can determine myocardial anatomy, function, perfusion, and viability in a relative short examination. In terms of viability assessment, CMR can determine viability in a non-contrast enhanced scan using dobutamine stress following protocols comparable to those developed for dobutamine echocardiography. CMR can also determine viability with late gadolinium enhancement (LGE) methods. The gadolinium-based contrast agents used for LGE differentiate viable myocardium from scar on the basis of differences in cell membrane integrity for acute myocardial infarction. In chronic myocardial infarction, the scarred tissue enhances much more than normal myocardium due to increases in extracellular volume. LGE is well validated in pre-clinical and clinical studies that now span from almost a cellular level in animals to human validations in a large international multicenter clinical trial. Beyond infarct size or infarct detection, LGE is a strong predictor of mortality and adverse cardiac events. CMR can also image microvascular obstruction and intracardiac thrombus. When combined with a measure of area at risk like T2-weighted images, CMR can determine infarct size, area at risk, and thus estimate myocardial salvage 1–7 days after acute myocardial infarction. Thus, CMR is a well validated technique that can assess viability by gadolinium-free dobutamine stress testing or late gadolinium enhancement.

Arai, Andrew E.

2012-01-01

155

A viability analysis of fishery controlled by investment rate.  

PubMed

This work presents a stock/effort model describing both harvested fish population and fishing effort dynamics. The fishing effort dynamic is controlled by investment which corresponds to the revenue proportion generated by the activity. The dynamics are subject to a set of economic and biological state constraints. The analytical study focuses on the compatibility between state constraints and controlled dynamics. By using the mathematical concept of viability kernel, we reveal situations and management options that guarantee a sustainable system. PMID:24002567

Sanogo, C; Raïssi, N; Ben Miled, S; Jerry, C

2013-09-04

156

Storage Viability and Optimization Web Service  

SciTech Connect

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-integer linear program (MILP) written and executed in the General Algebraic Modeling System (GAMS) optimization software. LBNL has released version 1.2.0.11 of SVOW. Information can be found at http://der.lbl.gov/microgrids-lbnl/current-project-storage-viability-website.

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

2010-10-11

157

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

PubMed Central

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 health systems and social policies are needed.

2012-01-01

158

Nanotechnology and economic resiliency  

Microsoft Academic Search

Today a country's economic viability and its citizens’ job mobility require that its workforce have a strong micro- and nanotechnology education providing a skill set covering synthesis, fabrication, and characterization. An international model is offered for creating such a skilled workforce which is based on a resource sharing approach between research universities and technical colleges. For the good of a

Stephen J. Fonash

2009-01-01

159

Viability of preserved Cryptosporidium baileyi oocysts.  

PubMed

The present study was undertaken to determine the viability and infectivity of oocysts of Cryptosporidium baileyi that had been stored from 1 to 40 months at 4 degrees C preserved in 2.5% potassium dichromate solution. Oocysts of C. baileyi were purified from the feces of experimentally infected chickens using discontinuous sucrose gradients. Subsequently, the purified oocysts were suspended in 2.5% potassium dichromate solution at a concentration of 1 x 10(7) organism/ml, and their viabilities were assessed by nucleic acid staining, histologic examination, and infectivity to 2-day-old chickens. All chickens inoculated with oocysts that had been stored for 1-18 months developed patent infections, while chickens infected with older oocysts remained uninfected. Between 5.8% and 82.2% of the oocysts, stored at 4 degrees C in 2.5% potassium dichromate solution, were found to be viable, as determined by nucleic acid staining. Parasite colonization in the bursa of Fabricius was detected in the microvillus border of bursal epithelium. The finding that C. baileyi oocysts remain infective to chickens for at least 18 months offers important time-saving advantages to investigators who frequently require large numbers of oocysts. PMID:14699260

Surl, Chan-Gu; Kim, Se-Min; Kim, Hyeon-Cheol

2003-12-01

160

Macro Economic Instability and Business Exit: Determinants of Failures and Acquisitions of Large UK Firms  

Microsoft Academic Search

Using data over a 34-year span on UK quoted firms, this paper seeks to identify the factors that increase the likelihood of exit of firms. Firms may disappear through the mutually precluding events of bankruptcies and acquisitions. We use a competing-risks hazard model to determine characteristics leading to each outcome. Hazard models make use of the data on timing of

Arnab Bhattacharjee; Chris Higson; Sean Holly; Paul A. Kattuman

2002-01-01

161

Economic Transition, Firm Organization, and Internal Control Determinants of Audit Structure in Russian firms  

Microsoft Academic Search

With a unique dataset of joint-stock companies, this paper aims to thoroughly describe the corporate audit structure in transition Russia and empirically analyze its determinants. When compared to the international standard, Russian firms have a weak audit structure in terms of the independence and expertise of the board of auditors and the accounting auditor. We found that board composition, affiliation

Ichiro Iwasaki

2010-01-01

162

Economic transition, firm organisation and internal control: determinants of audit structure in Russian firms  

Microsoft Academic Search

With a unique dataset of joint-stock companies, this paper describes the corporate audit structure in Russia and empirically analyses its determinants. When compared to the international standard, Russian firms have a weak audit structure in terms of the independence and expertise of the board of auditors and the accounting auditor. We found that board composition, affiliation with a business group

Ichiro Iwasaki; John van Reenen; Toby Wolfe

2011-01-01

163

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

PubMed

Options for treatment and discharge of wastewater in regional Western Australia (WA) are examined from the perspective of overall sustainability and social net benefit. Current practice in the state has typically involved a basic standard of treatment deemed to be protective of human health, followed by discharge to surface water bodies. Community and regulatory pressure to move to higher standards of treatment is based on the presumption that a higher standard of treatment is more protective of the environment and society, and thus is more sustainable. This analysis tests that hypothesis for Western Australian conditions. The merits of various wastewater treatment and discharge strategies are examined by quantifying financial costs (capital and operations), and by monetising the wider environmental and social costs and benefits of each option over an expanded planning horizon (30 years). Six technical treatment-disposal options were assessed at a test site, all of which met the fundamental criterion of protecting human health. From a financial perspective, the current business-as-usual option is preferred - it is the least cost solution. However, valuing externalities such as water, greenhouse gases, ecological impacts and community amenity, the status quo is revealed as sub-optimal. Advanced secondary treatment with stream disposal improves water quality and provides overall net benefit to society. All of the other options were net present value (NPV) negative. Sensitivity analysis shows that the favoured option outperforms all of the others under a wide range of financial and externality values and assumptions. Expanding the findings across the state reveals that moving from the identified socially optimal level of treatment to higher (tertiary) levels of treatment would result in a net loss to society equivalent to several hundred million dollars. In other words, everyone benefits from improving treatment to the optimum point. But society, the environment, and the Corporation are all worse off when treatment levels are pushed beyond what is economic and sustainable. PMID:23183146

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

2012-11-24

164

Cell viability test after laser guidance  

NASA Astrophysics Data System (ADS)

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.

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

2006-03-01

165

Rapid onsite assessment of spore viability.  

SciTech Connect

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.

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

2005-12-01

166

Modeling and simulation of novel method of single cell viability detection via electrical measurement using dual nanoprobes  

Microsoft Academic Search

Cell viability is important in biological studies. The detection of cell viability is simply checking whether the cell is alive or dead. This is important in experiments when cells are placed in a new foreign environment and when cells are being manipulated for testing either mechanically, chemically or electrically. Basically, there are two ways to determine the cell viability, one

Abdul Hafiz Mat Sulaiman; Mohd Ridzuan Ahmad

2012-01-01

167

Solar cooling technologies in Greece. An economic viability analysis  

Microsoft Academic Search

In Greece, during the summer, the demand for electricity greatly increases because of the extensive use of air-conditioning systems. This is a source of major problems in the country’s electricity supply and contributes to an increase of the CO2 emissions. The use of solar energy (SE) to drive cooling cycles is attractive since the cooling load is roughly in phase

Theocharis Tsoutsos; Joanna Anagnostou; Colin Pritchard; Michalis Karagiorgas; Dimosthenis Agoris

2003-01-01

168

Economic viability of photovoltaic power for development assistance applications  

SciTech Connect

This paper briefly discusses the development assistance market and examines a number of specific 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.

Bifano, W.J.

1982-09-01

169

The viability of skin flaps.  

PubMed Central

The historical development of skin flaps is outlined, and in particular their division into two types: random, which are supplied by small musculocutaneous vessels; and axial flaps, which are supplied by named cutaneous vessels running within the flap. Experiments are described into the viability of random skin flaps, using the pig as an experimental model. These experiments confirm that random flaps should not be designed longer than their base and probably should not exceed 12.5 cm (5 in) in length. Images Fig. 1

Stell, P. M.

1977-01-01

170

Meter-level orbit determination of geosynchronous satellites by an economical tracking system  

NASA Astrophysics Data System (ADS)

Covariance analyses to study the performance of a proposed high precision and low cost geosynchronous satellites tracking system are presented. The tracking systems main components are one TDRS, a near-by geosynchronous satellite, 4-5 automatic ground stations, and a Very Long Baseline Interferometric (VLBI) system. The automated ground station provides doubly differenced ranging measurements without precision clock. The VLBI system consists of 4 one meter antennas positioned on orthogonal 6000 km baselines and uses a GPS signal for clock synchronization. Based on the anticipated characteristics of the 1990 era VLBI system, doubly differenced ranging and dynamic model, a factor of 20 or better improvement can be expected in the TDRSS orbit determination accuracy. This would make the satellite-based delta-VLBI deep space navigation system more attractive than the other systems which have been proposed.

Culp, R. D.; Wang, T.-H.

171

Is the Spatial Distribution of Mankind's Most Basic Economic Traits Determined by Climate and Soil Alone?  

PubMed Central

Background Several authors, most prominently Jared Diamond (1997, Guns, Germs and Steel), have investigated biogeographic determinants of human history and civilization. The timing of the transition to an agricultural lifestyle, associated with steep population growth and consequent societal change, has been suggested to be affected by the availability of suitable organisms for domestication. These factors were shown to quantitatively explain some of the current global inequalities of economy and political power. Here, we advance this approach one step further by looking at climate and soil as sole determining factors. Methodology/Principal Findings As a simplistic ‘null model’, we assume that only climate and soil conditions affect the suitability of four basic landuse types – agriculture, sedentary animal husbandry, nomadic pastoralism and hunting-and-gathering. Using ecological niche modelling (ENM), we derive spatial predictions of the suitability for these four landuse traits and apply these to the Old World and Australia. We explore two aspects of the properties of these predictions, conflict potential and population density. In a calculation of overlap of landuse suitability, we map regions of potential conflict between landuse types. Results are congruent with a number of real, present or historical, regions of conflict between ethnic groups associated with different landuse traditions. Furthermore, we found that our model of agricultural suitability explains a considerable portion of population density variability. We mapped residuals from this correlation, finding geographically highly structured deviations that invite further investigation. We also found that ENM of agricultural suitability correlates with a metric of local wealth generation (Gross Domestic Product, Purchasing Power Parity). Conclusions/Significance From simplified assumptions on the links between climate, soil and landuse we are able to provide good predictions on complex features of human geography. The spatial distribution of deviations from ENM predictions identifies those regions requiring further investigation of potential explanations. Our findings and methodological approaches may be of applied interest, e.g., in the context of climate change.

Beck, Jan; Sieber, Andrea

2010-01-01

172

Predictive model for the determination of the economic feasibility of construction and demolition waste recycling in the Air Force. Master's thesis  

Microsoft Academic Search

This study created a model to be used at a CONUS Air Force base to determine the economic feasibility of Construction and Demolition (CD) waste recycling. Three areas investigated to develop this model: the methods to determine amounts and types of CD waste generated at a specific location, the markets for recycled CD wastes, and the recycling methods currently available.

1993-01-01

173

Local economic policies as determinants of the local business climate: Empirical results from a cross-section analysis among East German municipalities  

Microsoft Academic Search

Blume L. (2006) Local economic policies as determinants of the local business climate: empirical results from a cross-section analysis among East German municipalities, Regional Studies40, 321–333. For the period after 1995, there is empirical evidence that differences in East German local economic policies explain a significant part of the variation in the local business climate. A cross-section analysis among 92

Lorenz Blume

2006-01-01

174

Impact Of Asset Age\\/Fiscal Viability On Selected Measures Of Patient Care In Nursing Homes  

Microsoft Academic Search

Forty-five New York nursing homes were examined to determine if a relationship between age of assets, fiscal viability and quality of nursing homes, as measured by patient care indices and survey deficiencies, existed. These factors were examined on 2004 data for the nursing homes selected. Several financial variables were used to construct a fiscal viability index; and a patient care

Jim Morey

175

Applications of a Rapid Endospore Viability Assay for Monitoring UV Inactivation and Characterizing Arctic Ice Cores  

Microsoft Academic Search

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

Hannah S. Shafaat; Adrian Ponce

2006-01-01

176

HPC viability measurement: trypan blue versus acridine orange and propidium iodide  

Microsoft Academic Search

BACKGROUND: A reliable, validated method for rapidly determining HPC viability is essential for clinical cell en- gineering. STUDY DESIGN AND METHODS: A fluorometric cell viability assay using acridine orange and propidium io- dide (AO\\/PI) was compared to the current standard, trypan blue (TB) exclusion. Viable cells stained with AO\\/ PI fluoresce green under darkfield fluorescence micros- copy, while nonviable cells

K. Mascotti; J. McCullough; S. R. Burger

2000-01-01

177

Luminescent multiplex viability assay for Trypanosoma brucei gambiense  

PubMed Central

Background New compounds for the treatment of human African trypanosomiasis (HAT) are urgently required. Trypanosoma brucei (T.b.) gambiense is the leading cause of HAT, yet T.b. gambiense is often not the prime target organism in drug discovery. This may be attributed to the difficulties in handling this subspecies and the lack of an efficient viability assay to monitor drug efficacy. Methods In this study, a T.b. gambiense strain, recently isolated in the D.R. Congo, was made bioluminescent by transfection with Renilla luciferase (RLuc) without altering its in vitro and in vivo growth characteristics. A luminescent multiplex viability assay (LMVA), based on measurement of the Renilla luciferase activity and the ATP content of the cells within the same experiment, was investigated as an alternative to the standard fluorimetric resazurin viability assay for drug sensitivity testing of T.b. gambiense. Results In a 96-well format, the RLuc transfected strain showed a detection limit of 2 × 104 cells ml-1 for the Renilla luciferase measurement and 5 × 103 cells ml-1 for the ATP measurement. Both assays of the LMVA showed linearity up to 106 cells ml-1 and correlated well with the cell density during exponential growth of the long slender bloodstream forms. The LMVA was compared to the fluorimetric resazurin viability assay for drug sensitivity testing of pentamidine, eflornithine, nifurtimox and melarsoprol with both the wild type and the RLuc transfected population. For each drug, the IC50 value of the RLuc population was similar to that of the wild type when determined with either the fluorimetric resazurin method or the LMVA. For eflornithine, nifurtimox and melarsoprol we found no difference between the IC50 values in both viability assays. In contrast, the IC50 value of pentamidine was higher when determined with the fluorimetric resazurin method than in both assays of the LMVA. Conclusions LMVA has some advantages for viability measurement of T.b. gambiense: it requires less incubation time for viability detection than the fluorimetric resazurin assay and in LMVA, two sensitive and independent viability assays are performed in the same experiment.

2013-01-01

178

Ecological economics and economic growth.  

PubMed

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. PMID:20146773

Victor, Peter A

2010-01-01

179

Experiments with the Viability of Chicken Eggs  

ERIC Educational Resources Information Center

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)

Garigliano, Leonard J.

1975-01-01

180

Viability of piping plover Charadrius melodus metapopulations  

Microsoft Academic Search

The metapopulation viability analysis package, vortex, was used to examine viability and recovery objectives for piping plovers Charadrius melodus, an endangered shorebird that breeds in three distinct regions of North America. Baseline models indicate that while Atlantic Coast populations, under current management practices, are at little risk of near-term extinction, Great Plains and Great Lakes populations require 36% higher mean

Jonathan H Plissner; Susan M Haig

2000-01-01

181

Experiments with the Viability of Chicken Eggs  

ERIC Educational Resources Information Center

|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)|

Garigliano, Leonard J.

1975-01-01

182

Viability and predictive control for safe locomotion  

Microsoft Academic Search

The problem of safe locomotion of legged and wheeled robots, when trying to avoid falling, tipping over or hitting obstacles, appears to be a problem of viability and not of Lyapunov stability. Theoretically speaking, viability and Model Predictive Control are unquestionably related, but both can quickly lead to untractable numerical problems. We present here a promising approach for the problem

Pierre-brice Wieber

2008-01-01

183

Oil, the Suez canal, and sterling reserves: economic factors determining British decisionmaking during the 1967 Arab–Israeli crisis  

Microsoft Academic Search

This article assesses the importance of economic factors for the development of British Middle Eastern policy during the 1967 Arab-Israeli crisis, based on newly declassified government documents. Policy shifted from threatening unilateral action against Nasser to multilateralism and neutraliry shortly before the June war. Economic considerations will be put in the context of anti-interventionist voices in the cabinet, in the

Gernot Klantschnig

2003-01-01

184

Institutional Determinants of Economic Policymaking in Latin America 1978-2006: Legislative Bargaining, Separation of Powers, and Fiscal Policy  

Microsoft Academic Search

This paper aims to evaluate the effect of different institutional designs on the economic policymaking process and outcomes. I focus on the bargaining between executive and legislative branches of government over the definition of fiscal policy under separation of powers in presidential regimes. Using data for 17 countries in Latin America between 1977 and 2006, I argue that economic policymaking

Nestor Castaneda-Angarita

185

Quantitative preservation of viability of Aspergillus fumigatus.  

PubMed

Quantitative preservation of the viability of two isolates of Aspergillus fumigatus was studied over a 15-month period of storage. Significant loss of viability occurred in isolates preserved at -70 degrees C in both phosphate-buffered saline with Tween (PBST) and 0.1% gelatin, immediately, and between 6 and 15 months. Storage in 10% and 25% dimethyl sulphoxide at -70 degrees C was successful up to 8 weeks with gradual loss of viability later. PBST at 4 degrees C or room temperature, or 10% glycerol at -70 degrees C maintained 100% viability of the cultures up to 6 months and 15 months, respectively. To preserve 100% viability, long-term storage of A. fumigatus is best done in 10% glycerol in PBST at -70 degrees C compared with the other methods tested. PMID:1287169

Denning, D W; Clemons, K V; Stevens, D A

1992-01-01

186

Insecticide resistance and malaria vector control: the importance of fitness cost mechanisms in determining economically optimal control trajectories.  

PubMed

The evolutionary dynamics of insecticide resistance in harmful arthropods has economic implications, not only for the control of agricultural pests (as has been well studied), but also for the control of disease vectors, such as malaria-transmitting Anopheles mosquitoes. Previous economic work on insecticide resistance illustrates the policy relevance of knowing whether insecticide resistance mutations involve fitness costs. Using a theoretical model, this article investigates economically optimal strategies for controlling malaria-transmitting mosquitoes when there is the potential for mosquitoes to evolve resistance to insecticides. Consistent with previous literature, we find that fitness costs are a key element in the computation of economically optimal resistance management strategies. Additionally, our models indicate that different biological mechanisms underlying these fitness costs (e.g., increased adult mortality and/or decreased fecundity) can significantly alter economically optimal resistance management strategies. PMID:23448053

Brown, Zachary S; Dickinson, Katherine L; Kramer, Randall A

2013-02-01

187

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

NASA Astrophysics Data System (ADS)

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 analysis, policy options

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

2012-04-01

188

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

PubMed

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. PMID:20565070

Liu, Yunbao; Nair, Muraleedharan G

2010-07-23

189

Effects of cryoprotectants on viability of Lactobacillus reuteri CICC6226.  

PubMed

Freeze-drying is commonly used to preserve probiotics, but it could cause cell damage and loss of viability. The cryoprotectants play an important role in the conservation of viability during freeze-drying. In this study, we investigated the survival rates of Lactobacillus reuteri CICC6226 in the presence of cryoprotectants such as sucrose, trehalose, and reconstituted skim milk (RSM). In addition, we determined the activities of hexokinase (HK), pyruvate kinase (PK), lactate dehydrogenase (LDH), and ATPases immediately following the freeze-drying. The results showed that the differences in HK and PK activities with and without the cryoprotectants during freeze-drying were not significant, but cell viability and activities of LDH and ATPase were significantly different (P<0.01) prior to and after freeze-drying. Meanwhile, the results showed that the maintenance of the membrane integrity and fluidity was improved in the presence of the 10% trehalose or 10% RSM than other treatments during freeze-drying. These results have provided direct biochemical and metabolic evidence of injured cell during freeze-drying. Freeze-drying damaged membrane structure and function of cell and inactivated enzymes (LDH and ATPases). The results imply that LDH and ATPases are key markers and could be used to evaluate the effect of cryoprotectants on viability and metabolic activities of L. reuteri CICC6226 during freeze-drying. PMID:21626024

Li, Baokun; Tian, Fengwei; Liu, Xiaoming; Zhao, Jianxin; Zhang, Hao; Chen, Wei

2011-05-29

190

Effect of vinegar on the viability of Giardia duodenalis cysts.  

PubMed

The inactivation of Giardia duodenalis cysts by vinegar was investigated. Experiments were carried out in 100 ml volume of vinegar (acetic acid 4%), undiluted or diluted in distilled water in ratios of 1:1, 1:15.6, and 1:62.5 (vol/vol), which were inoculated with 5x10(5) cysts obtained from human feces. Experiments were performed at room temperature (21+/-1 degrees C) and at 4 degrees C. After contact times of 1.5 min, 10, 30, and 60 min, the cysts were recovered from the treatment fluid and subjected to an in vitro excystation assay to determine their viability. The relative viability, which was calculated in relation to controls (maximum excystation percentage), was significantly affected (p<0.1) by the vinegar concentration, contact time, and temperature. At 21+/-1 degrees C, no cysts remained viable after being treated with undiluted vinegar for 60 min, while the treatment with 1:1, 1:15.6, and 1:62.5 vinegar-water mixtures decreased the relative viability to 1.8%, 19.4%, and 56.4%, respectively. The relative viability after corresponding treatments at 4 degrees C also decreased, but 23.6% to 48.8% remained viable after 60 min, and thus complete inactivation was not obtained with any treatment at that temperature. PMID:18986724

Costa, Adriana Oliveira; Thomaz-Soccol, Vanete; Paulino, Rosangela Clara; Alcântara de Castro, Edilene

2008-10-11

191

Rural hospitals' viability and strategic responses.  

PubMed

In 1989 the Catholic Health Association, in conjunction with the University of Iowa Center for Health Services Research, surveyed chief executive officers (CEOs) of rural hospitals regarding their hospital's viability and strategic behaviors and orientations. An extensive questionnaire was sent to the CEOs of all Catholic, all other religious not-for-profit, and all investor-owned rural hospitals, as well as to a 50 percent random sample of government and other not-for-profit rural hospitals. CEOs on average perceived that their hospital's viability relative to that of other rural hospitals was higher in 1989 than it had been in 1987. Ninety-four percent of hospitals whose CEOs perceived an increase in viability had been medium- or low-viability hospitals two years earlier. Thus, despite reports of deteriorating conditions for rural hospitals, rural hospital CEOs appeared to be relatively optimistic regarding their institution's viability. Changes in strategic direction accompanied these perceived increases in viability. The predominant strategic orientation adopted by rural hospitals in 1987 was that of the defender, but many hospitals that used this approach switched to the analyzer orientation by 1989. Significant shifts also occurred toward the reactor orientation from the analyzer and defender orientations. A greater percentage of hospitals with a perceived increase in viability between 1987 and 1989 altered their organizational role. The most common change for these hospitals was from limited care to basic care. PMID:10117404

Ludke, R L; Westhoff, L J; Flood, B M

1992-05-01

192

Determination of Maximum Permissible Levels of Selected Chemicals that Exert Toxic Effects on Plants of Economic Importance in Illinois.  

National Technical Information Service (NTIS)

The publication deals with the toxic effects of pollutants on plants of economic importance in Illinois. The following pollutants were considered: Aluminum; barium; beryllium; boron; bromine; cadmium; carbon-ethylent; chlorine; chromium; copper; fluorine;...

J. H. Yopp R. W. Holst W. E. Schmid

1974-01-01

193

Assessment of skin flap viability using visible diffuse reflectance spectroscopy and auto-fluorescence spectroscopy  

NASA Astrophysics Data System (ADS)

The accurate assessment of skin flap viability is vitally important in reconstructive surgery. Early identification of vascular compromise increases the change of successful flap salvage. The ability to determine tissue viability intraoperatively is also extremely useful when the reconstructive surgeon must decide how to inset the flap and whether any tissue must be discarded. Visible diffuse reflectance and auto-fluorescence spectroscopy, which yield different sets of biochemical information, have not been used in the characterization of skin flap viability simultaneously to our best knowledge. We performed both diffuse reflectance and fluorescence measurements on a reverse MacFarlane rat dorsal skin flap model to identify the additional value of auto-fluorescence spectroscopy to the assessment of flap viability. Our result suggests that auto-fluorescence spectroscopy appears to be more sensitive to early biochemical changes in a failed flap than diffuse reflectance spectroscopy, which could be a valuable complement to diffuse reflectance spectroscopy for the assessment of flap viability.

Zhu, Caigang; Chen, Shuo; Chui, Christopher Hoe-Kong; Liu, Quan

2012-12-01

194

Assessing the viability of computational fluid dynamics (CFD) for siting small wind turbines in an urban area  

NASA Astrophysics Data System (ADS)

A complete wind resource assessment (WRA) in the urban area of SUNY-ESF was conducted using initial assessment, wind map examination, statistical analysis of measured wind data, and CFD modeling, for the potential installation of small wind turbines. Results consisting of mean wind velocity, annual energy prediction, turbulence, and net present value were used first to determine suitable locations for small wind turbines, and second to determine viability of each method of WRA. This study found that the CFD analysis provides a reasonably accurate and detailed analysis of wind resource in an urban area. The detailed level of analysis can ultimately lead to optimal economic decisions regarding installation, more so than the other explored methods. Also examined, were wind data sets from different locations for use as input data into the CFD model, ultimately finding that CFD output results can be significantly distorted with unsuitable data sets.

Pasco, Nicholas L.

195

A new fluorescent viability test for fungi cells  

Microsoft Academic Search

The fluorescein diacetate-ethidium bromide (FDA-EB) fluorescence method, primarily used to determine viability of mammalian cells, was applied to several fungi species. Living fungi cells produced fluorochromasia, i.e., an intracellular accumulation of fluorescein which could be easily visualized as a green color under the U.V. microscope. Dead cells showed a red bright color due to ethidium bromide penetration. The FDA-EB test

Vera Lúcia G. Calich; Adhemar Purchio; Claudete R. Paula

1979-01-01

196

Economics of Distance Education Reconsidered  

ERIC Educational Resources Information Center

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…

Laaser, Wolfram

2008-01-01

197

Access to Post-Compulsory Education and Training: Economic, Sociological and Political Determinants and Remaining Research Gaps  

ERIC Educational Resources Information Center

|This paper presents a review and assessment of existing theoretical accounts to explain differentials in access to education and training in advanced economies. These theories tend to focus on the analysis of the influence of a set of economic, sociological and political variables on access to education. Existing theories are criticized on two…

Otero, Manuel Souto

2007-01-01

198

The Convergence Theory Reconsidered: Political and Economic Determinants of Social Welfare Effort, A Cross-National Analysis.  

ERIC Educational Resources Information Center

|The convergence theory asserts that industrial nations are becoming increasingly alike due to their economic and technological development. Most interpretations of the convergence theory either state or imply that political factors are unimportant in shaping the common welfare state toward which all industrial nations are converging. Using data…

Weiss, Joseph W.; Williamson, John B.

199

The Paradox of Expected Punishment: Legal and Economic Factors Determining Success and Failure in the Fight against Organized Crime  

Microsoft Academic Search

The legal and economic analysis presented here empirically tests the theoretical framework advanced by Kugler, Verdier, and Zenou (2003) and Buscaglia (1997). This paper goes beyond the prior literature by focusing on the empirical assessment of the actual implementation of the institutional deterrence and prevention mechanisms contained in the United Nations’ Convention against Transnational Organized Crime (Palermo Convention). A sample

Edgardo Buscaglia

2008-01-01

200

Methods of Economic Analysis Applied to Fusion Research: Discount Rate Determination and the Fossil Fuel Price Effect.  

National Technical Information Service (NTIS)

In current and previous efforts, ECON has provided a preliminary economic assessment of a fusion research program. Part of this effort was the demonstration of a methodology for the estimation of reactor system costs and risk and for the treatment of prog...

1978-01-01

201

Economic openness and trade linkages of China: An empirical study of the determinants of chinese trade intensities from 1993 to 1999  

Microsoft Academic Search

In the 1980s, the Chinese regime took a number of piecemeal steps toward economic liberalization. This process accelerated\\u000a impressively in the 1990s. This paper reports an empirical study into the determinants of the emerging pattern of Chinese\\u000a trade (export and import) intensities in the liberalization decade by exploring international trade statistics for 1993 and\\u000a 1999. Four models are estimated that

Jianhong Zhang; Arjen van Witteloostuijn

2004-01-01

202

Viability of cartilage grafts in various forms.  

PubMed

The viability of cartilage grafts, in many forms, has been researched since the using of cartilage grafts in surgical procedures. Cryopreservation period and viability of cartilage grafts have remained unclear. This study was performed to investigate the durability, viability, and behavior of fresh or cryopreserved cartilage grafts when used as autografts or allografts in various forms.Six cartilage grafts (1 of each preparation type; 3 blocks and 3 diced) were prepared by wrapping with Surgicel or autogenous fascia, or they were left bare. After the graft preparation stage, the cartilage grafts were inserted into pockets prepared on the dorsum of each rabbit. Groups 1, 2, 3, and 4 (6 rabbits in each group) received autogenous fresh grafts, allogenous fresh grafts, autogenous cryopreserved grafts, and allogenous cryopreserved grafts, respectively. All cartilage grafts were implanted for 2 months.At the end of the second month, specimens were harvested and analyzed. The bare grafts provided the most viable specimens. There was no significant difference between the frozen or fresh and allograft or autograft groups with respect to viability and resorption ratios. The bare block graft, in all groups, survived significantly more than the other graft types.Allografts (homografts), similar autografts, did not create major problems, and they had excellent host tolerance and low antigenicity, especially when the perichondrium was removed. Viability and durability of the bare grafts (diced and block) were better than fascia or Surgicel-wrapped cartilage graft forms. PMID:21959409

Firat, Cemal; Gurlek, Ali; Aydin, Nasuhi Engin; Aydn, Nasuhi Engin

2011-09-01

203

Comparing a high-dose dipyridamole SPECT imaging protocol with dobutamine and exercise stress testing protocols. Part III: Using dobutamine to determine lung-to-heart ratios, left ventricular dysfunction, and a potential viability marker  

Microsoft Academic Search

Determination of the severity of coronary artery disease (CAD) by single photon emission computed tomography (SPECT) imaging has previously been shown to have greater sensitivity, specificity, and accuracy when performed with pharmacologic stress using dobutamine than by standard dose dipyridamole (SDD) or exercise stress testing (EST) prior to SPECT imaging. The use of lung to heart (L:H) ratios has been

Richard M. Fleming; Kristine M. Feldmann; Diane M. Fleming

1999-01-01

204

Bioenergy and economic development  

SciTech Connect

Bioenergy, a promising alternative for developing countries, is already a key resource (in the form of fuelwood, for example) in millions of households around the world. In this book, William Ramsay details the characteristics of a wide variety of bioenergy crops and discusses planning for bioenergy development, emphasising its economic, social, and political aspects. He also analyses how general cost trends, credit problems, and the pricing of alternative fuels affect the viability of various bioenergy options. Concluding with a discussion of how energy and national economic development planning can be coordinated, he argues that some kind of durable national or regional commitment to bioenergy programs is vital if bioenergy is to become a successful modern alternative to fuel and play a key role in the economic development process.

Ramsay, W.

1985-01-01

205

Sphingosine Kinase Activity Is Not Required for Tumor Cell Viability  

PubMed Central

Sphingosine kinases (SPHKs) are enzymes that phosphorylate the lipid sphingosine, leading to the formation of sphingosine-1-phosphate (S1P). In addition to the well established role of extracellular S1P as a mitogen and potent chemoattractant, SPHK activity has been postulated to be an important intracellular regulator of apoptosis. According to the proposed rheostat theory, SPHK activity shifts the intracellular balance from the pro-apoptotic sphingolipids ceramide and sphingosine to the mitogenic S1P, thereby determining the susceptibility of a cell to apoptotic stress. Despite numerous publications with supporting evidence, a clear experimental confirmation of the impact of this mechanism on tumor cell viability in vitro and in vivo has been hampered by the lack of suitable tool reagents. Utilizing a structure based design approach, we developed potent and specific SPHK1/2 inhibitors. These compounds completely inhibited intracellular S1P production in human cells and attenuated vascular permeability in mice, but did not lead to reduced tumor cell growth in vitro or in vivo. In addition, siRNA experiments targeting either SPHK1 or SPHK2 in a large panel of cell lines failed to demonstrate any statistically significant effects on cell viability. These results show that the SPHK rheostat does not play a major role in tumor cell viability, and that SPHKs might not be attractive targets for pharmacological intervention in the area of oncology.

Brown, Matthew L.; Carlson, Timothy; Coxon, Angela; Fajardo, Flordeliza; Frank, Brendon; Gustin, Darin; Kamb, Alexander; Kassner, Paul D.; Li, Shyun; Li, Yihong; Morgenstern, Kurt; Plant, Matthew; Quon, Kim; Ruefli-Brasse, Astrid; Schmidt, Joanna; Swearingen, Elissa; Walker, Nigel; Wang, Zhulun; Watson, J. E. Vivienne; Wickramasinghe, Dineli; Wong, Mariwil; Xu, Guifen; Wesche, Holger

2013-01-01

206

Viability and apoptosis in spermatozoa of transgenic rabbits.  

PubMed

The aim of our study was to compare the viability of sperm cells from transgenic (mWAP-hFVIII gene) or non-transgenic (normal) rabbit males as assessed by viability (SYBR-14/PI) and apoptosis (annexin V) tests. These results were evaluated using female conception rates following insemination with the respective sperm samples. No significant differences were found in concentration and motility between transgenic and non-transgenic spermatozoa. Spermatozoa from both transgenic (63.05 ± 20.05%) or non-transgenic (65.75 ± 22.15%) males, stained with SYBR-14 (green), were found to be morphologically normal. In both groups, the highest proportion of annexin V-positive sperm staining was found in the post-acrosomal part of the sperm head (8.66 and 27.53%). The percentage of sperm that stained with SYBR-14/PI or with annexin V/DAPI was correlated with liveborn in transgenic rabbits (R2 = 0.6118 and R2 = 0.2187, respectively) or non-transgenic rabbits (R2 = 0.671 and R2 = 0.3579, respectively). These data indicate that there was no difference in the viability of rabbit transgenic and non-transgenic spermatozoa when determined by both fluorescence assays. PMID:21144118

Chrenek, P; Makarevich, A V; Simon, M

2010-12-13

207

Sphingosine kinase activity is not required for tumor cell viability.  

PubMed

Sphingosine kinases (SPHKs) are enzymes that phosphorylate the lipid sphingosine, leading to the formation of sphingosine-1-phosphate (S1P). In addition to the well established role of extracellular S1P as a mitogen and potent chemoattractant, SPHK activity has been postulated to be an important intracellular regulator of apoptosis. According to the proposed rheostat theory, SPHK activity shifts the intracellular balance from the pro-apoptotic sphingolipids ceramide and sphingosine to the mitogenic S1P, thereby determining the susceptibility of a cell to apoptotic stress. Despite numerous publications with supporting evidence, a clear experimental confirmation of the impact of this mechanism on tumor cell viability in vitro and in vivo has been hampered by the lack of suitable tool reagents. Utilizing a structure based design approach, we developed potent and specific SPHK1/2 inhibitors. These compounds completely inhibited intracellular S1P production in human cells and attenuated vascular permeability in mice, but did not lead to reduced tumor cell growth in vitro or in vivo. In addition, siRNA experiments targeting either SPHK1 or SPHK2 in a large panel of cell lines failed to demonstrate any statistically significant effects on cell viability. These results show that the SPHK rheostat does not play a major role in tumor cell viability, and that SPHKs might not be attractive targets for pharmacological intervention in the area of oncology. PMID:23861887

Rex, Karen; Jeffries, Shawn; Brown, Matthew L; Carlson, Timothy; Coxon, Angela; Fajardo, Flordeliza; Frank, Brendon; Gustin, Darin; Kamb, Alexander; Kassner, Paul D; Li, Shyun; Li, Yihong; Morgenstern, Kurt; Plant, Matthew; Quon, Kim; Ruefli-Brasse, Astrid; Schmidt, Joanna; Swearingen, Elissa; Walker, Nigel; Wang, Zhulun; Watson, J E Vivienne; Wickramasinghe, Dineli; Wong, Mariwil; Xu, Guifen; Wesche, Holger

2013-07-05

208

Autofluorescence as a viability marker for detection of bacterial spores.  

PubMed

Recent biological terrorism events have indicated that bacterial spores such as Bacillus anthracis are real threat agents. Real time detection of biological agents is possible with the use of an ultraviolet Fluorescent Aerodynamic Particle Sizer (FLAPS) that measures particles' intrinsic fluorescence. It is important to know whether intrinsic fluorescence could be used to estimate agents' viability. Two categories of Bacillus spore populations can be differentiated by the intensity of intrinsic fluorescence emitted by ultraviolet (UV) stimulation : autofluorescent and non-autofluorescent. This study was performed to determine whether intensity of autofluorescence correlates with spore viability. Spores were analyzed using flow cytometer (equipped with a cell sorter) to mimic optical properties of FLAPS. Autofluorescent and non-autofluorescent spores were sorted according to the intensity of autofluorescence emitted following UV stimulation. Culturability, membrane integrity, membrane potential and dipicolinic acid (DPA) content were assessed. Autofluorescent spores were 1.7 times more culturable than the corresponding non-autofluorescent population. Moreover, a small proportion of autofluorescent spores exhibited extracellular membrane damages. Autofluorescent spores also showed higher membrane potential activity and contained higher levels of DPA. In conclusion, this study documents that the overall viability potential of bacterial spores can be assessed by UV flow cytometry used in the FLAPS technology. PMID:15769654

Laflamme, Christian; Verreault, Daniel; Lavigne, Sophie; Trudel, Luc; Ho, Jim; Duchaine, Caroline

2005-05-01

209

Metronidazole Decreases Viability of DLD-1 Colorectal Cancer Cell Line.  

PubMed

Abstract 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??g/mL after 24 hours; 0.1, 10, 50, and 250??g/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. PMID:23777253

Sadowska, Anna; Kr?towski, Rafa?; Szynaka, Beata; Cechowska-Pasko, Marzanna; Car, Halina

2013-06-18

210

Religion and Economic Growth  

Microsoft Academic Search

Empirical research on the determinants of economic growth has typically neglected the influence of religion. To fill this gap, we use international survey data on religiosity for a broad panel of countries to investigate the effects of church attendance and religious beliefs on economic growth. To isolate the direction of causation from religiosity to economic performance, we use instrumental variables

Robert J. Barro; Rachel M. Mccleary

2003-01-01

211

Crop productivity and economics during the transition to alternative cropping systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Increasing economic pressures and continued environmental concerns in agricultural production have heightened the need for more sustainable cropping systems. Research is needed to identify systems that simultaneously improve the economic and social viability of farms and rural communities while prot...

212

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

PubMed Central

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.

2011-01-01

213

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

Microsoft Academic Search

Fluorescein diacetate (FDA) was used as a vital stain to assay membrane integrity (cell viability) in meso- carp 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

Mark Krasnow; Mark Matthews; Ken Shackel

2008-01-01

214

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

PubMed

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. PMID:21976326

Woolf, Steven H; Braveman, Paula

2011-10-01

215

Rural Education and Rural Community Viability.  

ERIC Educational Resources Information Center

|This thesis examines the ways in which rural schools support or undermine rural community viability in the United States. Beginning in the late 19th century, the diverse people of the United States came under the power of a single ideology of modernization and the superiority of urban culture. This ideology has resulted in the American transition…

Hammer, Patricia Cahape

216

Viability of smallholder dairying in Wedza, Zimbabwe.  

PubMed

Viability differences in smallholder dairy farming are a result of differences in access to markets and services. It is hypothesized that innovations that improve productivity and market linkages also improve returns and viability. The viability of smallholder dairying in Wedza was characterised by interviewing 52 households using semi-structured questionnaires. Information on demographics, production, marketing, livestock numbers, assets and constraints was obtained. Farmers were resource-constrained with differences in access to resources. The highly resourced farmers had higher milk output and numbers of livestock. Almost 40 % of the households were female-headed, and these dominated the poor category. Household sizes ranged from 4 to 13 persons. Milk off-take was low (3.7 ± 0.53 l/cow/day), due to various constraints. Only rich farmers had viable enterprises in purely financial terms. Per litre cost of milk was more than selling price (US$0.96) for most farmers except the relatively rich. Operating ratios were 1.7, 0.6, 1.4 and 1.1 for the poor, rich, sub-centre and milk collection centre farmers, respectively. This means incomes from the dairy activities did not cover costs. Sensitivity analysis indicated that increases in total variable costs and labour reduced returns. Milk production and viability were influenced by access to resources and markets. PMID:23212836

Zvinorova, Plaxedis Ivy; Halimani, Tinyiko Edward; Mano, Renneth T; Ngongoni, Nobbert Takarwirwa

2012-12-05

217

Optimal optical trap for bacterial viability  

NASA Astrophysics Data System (ADS)

Optical trapping is a powerful tool for the micromanipulation of living cells—especially bacteria—but photodamage induced by the laser beam can adversely affect viability. We have explored optical trapping conditions in the near infrared (840-930nm) that preserve the viability of E. coli, as measured by gene expression of green fluorescent protein. We have found that time-sharing the optical traps, i.e., dwelling only 10?s-1ms on the cell, improves viability relative to continuous wave (CW) exposure for the same exposure time. We have also observed that similar to CW traps the photodamage in a time-shared trap depends weakly on wavelength, but linearly on peak power, implying an effect induced by single photon absorption. Taken altogether, integrating the exposure time and peak power, the data indicate that there is a lethal energy dose of about 5J for E. coli. Thus a single parameter—the energy—can be used to describe the limitation on viability.

Mirsaidov, Utkur; Timp, Winston; Timp, Kaethe; Mir, Mustafa; Matsudaira, Paul; Timp, Gregory

2008-08-01

218

Population Viability Analysis for an Endangered Plant  

Microsoft Academic Search

Demographic modeling is used to understand the Resumen: En este trabajo se emplea el modelaje de- population viability of Furbish's lousewort, Pedicularis fur- mografico para esclarecer la viabilidad poblacional de la bishiae, a perennial plant species endemic to the St. John planta perenne Pedicularis furbishiae, (Furbish's lousewort), River Valley in northern Maine. Environment-specific sum- enddmica al valle del rio S£

ERIC S. MENGES

1990-01-01

219

Gonzales, Casey and the Viability Rule  

Microsoft Academic Search

Gonzales v. Carhart upheld a federal ban on intact D&E abortions. The dissenters in Gonzales accused the majority of ignoring the rule that a state may only prohibit abortion of a viable fetus, one capable of life outside the womb. The continuing discord over the viability rule highlights an issue that remains unsettled 34 years after Roe: Why may a

Randy Beck

2009-01-01

220

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

PubMed

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. PMID:22231930

Arrighi, James A; Dilsizian, Vasken

2012-04-01

221

Human telomerase reverse transcriptase antisense treatment downregulates the viability of prostate cancer cells in vitro.  

PubMed

Telomerase, a ribonucleoprotein complex is activated in the vast majority of human malignancies, including prostate cancer. Its inhibition is a putative way to affect cancer proliferation and might be used in the therapy of tumors. We analysed the influence of antisense phosphorothioate oligonucleotides (PTO) against the reverse transcriptase subunit of telomerase on prostate cancer cell viability, telomerase activity and telomere length. DU145 prostate cancer cells were cultivated in PTO containing medium. The PTO-incorporation was confirmed by confocal laser scanning microscopy. Cell viability was measured by a WST-1 tetrazolium assay. After 15 days of antisense PTO treatment, a significant inhibition of cell viability occurred. Telomerase activity was determined by a telomeric repeat amplification protocol (TRAP) assay and telomere length by Southern blot analysis. Since the long-term telomerase antisense treatment reduces the viability of prostate cancer cells significantly, this antisense approach could be a new therapeutic strategy to treat patients with advanced prostate cancer. PMID:11408918

Schindler, A; Fiedler, U; Meye, A; Schmidt, U; Füssel, S; Pilarsky, C; Herrmann, J; Wirth, M P

2001-07-01

222

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

SciTech Connect

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.

Not Available

1980-05-01

223

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

NASA Astrophysics Data System (ADS)

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.

1980-09-01

224

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

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.

Downing, M.; Graham, R.L.

1993-12-31

225

Finding the economics in economic entomology.  

PubMed

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. PMID:19253610

Onstad, David W; Knolhoff, Lisa M

2009-02-01

226

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

Microsoft Academic Search

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

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

2004-01-01

227

Viability and storage of bromeliad pollen  

Microsoft Academic Search

Several bromeliad species from two different subfamilies, were used to develop a reliable method to evaluate pollen viability.\\u000a Pollen germination on a medium containing 20% sucrose, 0.001%H3BO3 and 0.5% agar was comparable to germination on a compatible stigma. Maximum germination was reached within 2 to 10 hours\\u000a depending on the species. Based on this test, six species were considered as

E. Parton; I. Vervaeke; R. Delen; B. Vandenbussche; R. Deroose; M. De Proft

2002-01-01

228

The Effect of Centrifugation Condition on Mature Adipocytes and Adipose Stem Cell Viability.  

PubMed

Different researchers have recommended different lipoaspirate centrifugation speeds and times, probably due to the limits in fat cell viability assays. We assessed fat cell viability using a fluorescein diacetate and propidium iodide (FDA-PI) stain and 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay after harvesting syringe liposuction and spun with different centrifugation speeds to determine the optimal conditions. Lipoaspirates, harvested from 13 donors, were transferred into a centrifuge tube and spun at 1000, 3000, and 4000 rpm for 3 minutes. Mature adipocytes and adipose stem cells were isolated and tested with a direct counting of FDA-PI-stained cells under fluorescence microscope and XTT assay. We incubated adipocytes and adipose stem cells for 1 day and 3 days, and we compared both of them with fresh samples to evaluate the influence of culturing condition on fat cell viability. Centrifugation speeds from 1000 rpm to 4000 rpm for 3 minutes showed no change in the percentage of adipocytes and adipose stem cell viability not only in the fresh samples but also in the cultured samples (1 day and 3 days). Centrifugation speeds under 4000 rpm do not change the percentage of fat cell viability. To differentiate viable cells from dying or dead mature adipocytes and oil accurately, combinations of viability tests are essential. PMID:23636113

Son, Daegu; Choi, Taehyun; Yeo, Hyeonjung; Kim, Junhyung; Han, Kihwan

2013-04-30

229

Estimation of Pollen Viability, Shedding Pattern, and Longevity of Creeping Bentgrass on Artificial Media  

Microsoft Academic Search

be determined. Pollen longevity may also be studied, which will facilitate the estimation of how far viable An estimation of pollen viability is needed to determine pollen daily pollen can potentially travel. This information may then shedding pattern and longevity. Both parameters provide valuable information for plant breeding and contribute to the risk assessment be used to better develop guidelines

S. Fei; E. Nelson

2003-01-01

230

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

ERIC Educational Resources Information Center

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,…

Jaumotte, Florence; Pain, Nigel

2005-01-01

231

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

ERIC Educational Resources Information Center

|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,…

Jaumotte, Florence; Pain, Nigel

2005-01-01

232

Towards "Lisbon Objectives": Economic Determinants of Participation Rates in University Education--An Empirical Analysis in 14 European Countries  

ERIC Educational Resources Information Center

Participation rates in higher education are an important indicator to pursue one of the main European policy objectives, which is to increase the proportion of population attending higher education. A model used to detect the determinants of participation rates is proposed in this paper, and it is empirically tested for 14 European countries…

Agasisti, Tommaso

2009-01-01

233

Towards "Lisbon Objectives": Economic Determinants of Participation Rates in University Education--An Empirical Analysis in 14 European Countries  

ERIC Educational Resources Information Center

|Participation rates in higher education are an important indicator to pursue one of the main European policy objectives, which is to increase the proportion of population attending higher education. A model used to detect the determinants of participation rates is proposed in this paper, and it is empirically tested for 14 European countries…

Agasisti, Tommaso

2009-01-01

234

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

PubMed Central

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 population size are expressed at the end of the species' life history.

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

2004-01-01

235

Assessing yeast viability from cell size measurements?  

PubMed

During microbial cell cultures, environmental conditions affect cell physiology and subsequently process efficiency. Physiological changes result in changing cell morphology, such as cell size variations. The aim of this work was to study cell size evolution of a Saccharomyces cerevisiae population exposed to various stresses during alcoholic batch fermentations, and to evaluate the potential use of cell size measurements to infer cell viability. During a reference culture, without perturbation, viability as assessed by propidium iodide staining (PI) remained 100% and mean cell diameter was found to be above 5microm. A rapid temperature shift from 33 to 43 degrees C at 50gl(-1) of ethanol resulted in an immediate arrest of growth and triggered a progressive loss of viability from 100% to 0% and a decrease of mean cell diameter from 5.2 to 3.7microm. Cell size distribution curves obtained with a cell counter showed an increasing subpopulation of significantly smaller cells. At single-cell level, combined microscopy size measurements and PI staining showed that this subpopulation was exclusively composed of dead cells. Similar results were obtained after acetic acid or furfural additions. Accordingly, a multivariate data analysis was achieved to estimate the ratio of dead cells from cell size distributions obtained using the cell counter. PMID:20599572

Tibayrenc, Pierre; Preziosi-Belloy, Laurence; Roger, Jean-Michel; Ghommidh, Charles

2010-06-25

236

Routine assessment of viability in split-thickness skin.  

PubMed

Effective quality control of allograft skin that is cryopreserved for transplantation requires a simple, reproducible technique for the assessment of cell viability. Tetrazolium reduction assays and an oxygen consumption technique have been the two methods of choice to determine the metabolic function of allograft skin after it has been thawed. In this study, we investigated the use of a novel tetrazolium salt, WST-1 (4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzen e disulfonate), that is cleaved to a water-soluble formazan product. Porcine split-thickness skin in minimal essential medium without cryoprotectant was subjected to a graded freezing protocol to generate progressive amounts of cryoinjury. Recovery as determined with WST-1 was compared with measurements made with the use of the oxygen consumption technique. The similarity of the resulting recovery curves indicates that WST-1 is a simple, effective, and convenient technique for the assessment of metabolic function in porcine split-thickness skin. The WST-1 assay is applicable for the routine assessment of tissue viability in cryopreserved allograft skin. PMID:10752741

Yang, H; Jia, X M; Acker, J P; Lung, G; McGann, L E

237

An analysis of the determinants in Economics and Business publications by Spanish universities between 1994 and 2004  

Microsoft Academic Search

The objective of this study consists, firstly, of quantifying differences between Spanish universities’ output (in terms of\\u000a publications and citations), and secondly, analysing its determinants. The results obtained show that there are factors which\\u000a have a positive influence on these indicators, such as having a third-cycle programme, with public financing obtained in competitive\\u000a selection procedures, having a large number of

Raúl Ramos; Vicente Royuela; Jordi Suriñach

2007-01-01

238

Viability of Multimedia Retrieval Systems for Marketing and Sales.  

National Technical Information Service (NTIS)

The thesis addresses the issue of the viability of Multimedia Retrieval Systems (MRSs) for Marketing & Sales (M&S). The study focuses on increasing insight into viability, and factors influencing viability, to improve MRSs for M&S and the way they are dev...

M. J. Hoogeveen

1994-01-01

239

Social and Economic Determinants of Disparities in Professional Help-Seeking for Child Mental Health Problems: Evidence from a National Sample  

PubMed Central

Objective To test the role of social determinants—including race, education, income, and demographic factors—of child mental health services use, defined as having had a visit to a mental health professional for depression, attention-deficit, or for any reason. Data Sources/Study Setting National Longitudinal Survey of Youth and the Child/Young Adult supplement, a nationally representative sample of 7–14-year-old children born to women who were 14–22 years old at the start of data collection, in 1979. African Americans and Latinos were over-sampled, and population weights are available to make nationally representative inferences. Study Design Indicators of mental health service use were regressed on social and economic determinants, family structure variables, and insurance variables, controlling for need as captured by several different symptom scales. Principal Findings Girls are much less likely to obtain needed treatment for externalizing behavior disorders than are boys, and are somewhat less likely to obtain needed treatment for depression than boys. Middle children are less likely to obtain needed treatment for any mental health problem than are oldest, youngest, or only children. The presence of the father inhibits the likelihood that the child will receive treatment, particularly for depression. African Americans and Latinos are less likely than white children to receive treatment. In contrast to these rich results for the social and demographic determinants of children's specialty mental health utilization, the economic and insurance variables (including maternal education and income) seem to hold little predictive power. Conclusions These results argue for interventions to sensitize parents—especially fathers—to the need to pay attention to the mental health needs of their children, in particular girls and middle children. The analysis also suggests that the literature on intrahousehold decision making and on the gender dimensions of investment in children is worth extending to mental health treatment decisions.

Zimmerman, Frederick J

2005-01-01

240

Economic Imperialism  

Microsoft Academic Search

Economics is not only a social science, it is a genuine science. Like the physical sciences, economics uses a methodology that produces refutable implications and tests these implications using solid statistical techniques. In particular, economics stresses three factors that distinguish it from other social sciences. Economists use the construct of rational individuals who engage in maximizing behavior. Economic models adhere

Edward P. Lazear

2000-01-01

241

Economic Imperialism  

Microsoft Academic Search

Economics is not only a social science, it is a genuine science. Like the physical sciences, economics uses a methodology that produces refutable implications and tests these implications using solid statistical techniques. In particular, economics stresses three factors that distinguish it from other social sciences. Economists use the construct of rational individuals who engage in maximizing behavior. Economic models adhere

Edward P. Lazear

1999-01-01

242

Quintessence reconstructed: New constraints and tracker viability  

SciTech Connect

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.

Sahlen, Martin; Liddle, Andrew R.; Parkinson, David [Astronomy Centre, University of Sussex, Brighton BN1 9QH (United Kingdom)

2007-01-15

243

Resilience and vulnerability to a natural hazard: A mathematical framework based on viability theory  

NASA Astrophysics Data System (ADS)

This deals with the response of a coupled human and natural system (CHANS) to a natural hazard by using the concepts of resilience and vulnerability within the mathematical framework of viability theory. This theory applies to time-evolving systems such as CHANS and assumes that their desirable properties can be defined as a subset of their state space. Policies can also apply to influence the dynamics of such systems: viability theory aims at finding the policies which keep the properties of a controlled dynamical system for so long as no disturbance hits it. The states of the system such that the properties are guaranteed constitute what is called the viability kernel. This viability framework has been extended to describe the response to a perturbation such as a natural hazard. Resilience describes the capacity of the CHANS to recover by getting back in the viability kernel, where its properties are guaranteed until the onset of the next major event. Defined for a given controlled trajectory that the system may take after the event ends, resilience is (a) whether the system comes back to the viability kernel within a given budget such as a time constraint, but also (b) a decreasing function of vulnerability. Computed for a given trajectory as well, 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 a certain trajectory. There can be several vulnerability functions, representing for instance social, economic or ecological vulnerability, and each representing the violation of an associated property, but these functions need to be ultimately aggregated as a single indicator. Computing the resilience and vulnerability of a trajectory enables the viability framework to describe the response of both deterministic and stochastic systems to hazards. In the deterministic case, there is only one response trajectory for a given action policy, and methods exist to find the actions which yield the most resilient trajectory, namely the least vulnerable trajectory for which recovery is complete. In the stochastic case however, there is a range of possible trajectories. Statistics can be derived from the probability distribution of the resilience and vulnerability of the trajectories. Dynamic programming methods can then yield either the policies that maximize the probability of being resilient by achieving recovery within a given time horizon, or these which minimize a given vulnerability statistic. These objectives are different and can be in contradiction, so that trade-offs may have to be considered between them. The approach is illustrated in both the deterministic and stochastic cases through a simple model of lake eutrophication, for which the desirable ecological properties of the lake conflict with the economic interest of neighboring farmers.

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

2013-04-01

244

Development and validation of a highly sensitive economic enzymeimmunoassay for prolactin determination in blood plasma of mithun (bos frontalis) and its application during milk let down and cyclicity.  

PubMed

The objective of the present study was to develop and validate highly sensitive and economic enzymeimmunoassay (EIA) for prolactin determination in mithun blood plasma on microtitreplates using the biotin-streptavidin amplification system and second antibody coating technique and to apply this procedure during milk let down and cyclicity in mithuns (Bos frontalis), a semi-wild ruminant. Biotin was coupled to prolactin and used to bridge between streptavidin peroxidase and immobilized antiserum in competitive assay. The EIA was carried out directly in 50 microl mithun plasma. The sensitivity of the EIA procedure was 0.1 ng/ml plasma. Plasma volumes viz., 12.5, 25 and 50 microl did not influence much the shape of standard curve though a slight drop in the OD450 was seen with higher plasma volumes. A parallelism test was carried out to compare the endogenous mithun plasma prolactin with bovine prolactin standards used in the assay. It showed good parallelism with the bovine standard curve. Plasma prolactin was estimated in six cyclic mithun cows during an estrous cycle. Mean plasma prolactin concentrations around the day of estrus were recorded to be higher than any other day of the cycle. Prolactin profiles were also obtained in three mithuns before, during and after milking. A sharp release of prolactin shortly after udder stimulation was observed. High levels of prolactin were maintained during milking, falling sharply thereafter. In conclusion, the EIA developed for prolactin determination in mithun blood plasma is sufficiently reliable, economic and sensitive enough to estimate prolactin in all physiological variation in mithun. PMID:16769186

Mondal, Mohan; Rajikhowa, Chandan; Prakash, B S

2007-05-01

245

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

NASA Astrophysics Data System (ADS)

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 several vulnerability functions, representing for instance social, economic or ecological vulnerability, and each representing the violation of the associated property, but these functions need to be ultimately aggregated as a single indicator. Due to the stochastic nature of the system, there is a range of possible trajectories. Statistics can be derived from the probability distribution of the vulnerability of the trajectories. Dynamic programming methods can then yield the policies which, among available policies, minimize a given trajectory. Thus, this viability framework gives indication on both the possible consequences of a hazard or an environmental change, and on the policies that can mitigate or avert it. It also enables to assess the benefits of extending the set of available policy options, and we define adaptive capacity as the reduction in a given vulnerability statistic due to the introduction of new policy options.

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

2013-04-01

246

Microbial and environmental effects on avian egg viability: do tropical mechanisms act in a temperate environment?  

PubMed

The viability of freshly laid avian eggs declines after several days of exposure to ambient temperatures above physiological zero, and declines occur faster in tropical than temperate ecosystems. Microbial infection during preincubation exposure has recently been shown as a second cause of egg viability decline in the tropics, but whether microbial processes influence the viability of wild bird eggs in temperate ecosystems is unknown. We determined the microbial load on eggshells, the incidence of microbial penetration of egg contents, and changes in the viability of wild bird eggs (Sialia mexicana, Tachycineta bicolor, Tachycineta thalassina) experimentally exposed to temperate-zone ambient conditions in situ in a mediterranean climate in northern California. Initial microbial loads on eggshells were generally low, although they were significantly higher on eggs laid in old boxes than in new boxes. Eggshell microbial loads did not increase with exposure to ambient conditions, were not reduced by twice-daily disinfection with alcohol, and were unaffected by parental incubation. The rate of microbial penetration into egg contents was low and unaffected by the duration of exposure. Nevertheless, egg viability declined very gradually and significantly with exposure duration, and the rate of decline differed among species. In contrast to studies performed in the tropics, we found little evidence that temperature or microbial mechanisms of egg viability decline were important at our temperate-zone site; neither temperatures above physiological zero nor alcohol disinfection was significantly related to hatching success. Delaying the onset of incubation until the penultimate or last egg of a clutch at our study site may maintain hatching synchrony without a large trade-off in egg viability. These results provide insight into the environmental mechanisms that may be responsible for large-scale latitudinal patterns in avian clutch size and hatching asynchrony. PMID:21661574

Wang, Jennifer M; Firestone, Mary K; Beissinger, Steven R

2011-05-01

247

Evaluation of the Cell Viability of Human Wharton's Jelly Stem Cells for Use in Cell Therapy  

PubMed Central

Human umbilical cord Wharton's jelly stem cells (HWJSCs) are gaining attention as a possible clinical source of mesenchymal stem cells for cell therapy and tissue engineering due to their high accessibility, expansion potential, and plasticity. We employed a combination of highly sensitive techniques to determine the average cell viability levels and proliferation capabilities of 10 consecutive cell passages of cultured HWJSCs and then used RNA microarrays to identify genes associated with changes in cell viability levels. We found an initial decrease in cell viability from the first to the third cell passage followed by an increase until the sixth passage and a final decrease from the sixth to tenth cell passages. The highest cell viability levels corresponded to the fifth and sixth passages. The intracellular ionic contents of potassium, sodium, and chlorine suggest that the lower cell viability levels at passages 2, 3, and 8–10 may be associated with apoptotic cell death. In fact, gene expression analysis revealed that the average cell viability was significantly associated with genes with a function in apoptotic cell death, especially pro-apoptotic FASTKD2, BNIP3L genes and anti-apoptotic TNFAIP8 and BCL2L2 genes. This correlation with both pro-apoptotic and anti-apoptotic genes suggests that there may be a complex live-death equilibrium in cultured HWJSCs kept in culture for multiple cell passages. In this study, the highest cell viability levels corresponded to the fifth and sixth HWJSC passages, suggesting that these passages should be preferentially employed in cell therapy or tissue engineering protocols using this cell type.

Garzon, Ingrid; Perez-Kohler, Barbara; Garrido-Gomez, Juan; Carriel, Victor; Nieto-Aguilar, Renato; Martin-Piedra, Miguel Angel; Garcia-Honduvilla, Natalio; Bujan, Julia; Campos, Antonio

2012-01-01

248

Cell viability in a wet silica gel.  

PubMed

A modified two-step sol-gel route using silicon ethoxide (TEOS) has been used to synthesize amorphous sol-gel-derived silica, which has been successfully used as a cell encapsulation matrix for 3T3 mouse fibroblasts and CRL-2595 epithelial cells due to its non-toxicity. The sol-gel procedure comprised a first, low pH hydrolysis step, followed by a neutral condensation-gelation step. A high water-to-TEOS ratio and the addition of d-glucose as a porogen and source of nutrients were chosen to minimize silica dissolution and improve the biocompatibility of the process. Indeed, the cell integrity in the encapsulation process was preserved by alcohol removal from the starting solution. Cells were then added in a buffered medium, causing rapid gelation and entrapment of the cells within a randomly structured siloxane matrix in the shape of a monolith, which was maintained in the wet state. MTT and alamarBlue assays were used to check the cytotoxicity of the silica gels and the viability of entrapped cells at initial times in contact with silica. To improve cell attachment, cell clumping experiments - where groups of cells were formed - were designed, rendering improved viability. The obtained materials are therefore excellent candidates for designing tissue-culture scaffolds and implantable bioreactors for biomedical applications. PMID:19481618

Nieto, Alejandra; Areva, Sami; Wilson, Timothy; Viitala, Reeta; Vallet-Regi, Maria

2009-05-28

249

Population Viability Analysis of Riverine Fishes  

SciTech Connect

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).

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

1999-04-12

250

Myocardial viability assessment in 18FDG PET/CT study (18FDG PET myocardial viability assessment).  

PubMed

Accurate identification of viable myocardium is crucial in patient qualification for medical or surgical treatment. Only persons with confirmed cardiac viability will benefit from revascularization procedures. It is also well known, that the amount of viable myocardium assessed preoperatively is the best indicator of long term cardiac event free survival after cardiac intervention.There are several diagnostic approaches used in current clinical practice for assessment of myocardial viability. Analysis of wall thickness or myocardial contraction, evaluation of cardiac perfusion or metabolism can be assessed using following modalities: Echocardiography, Cardiac Molecular Imaging techniques (PET, SPECT), Cardiovascular MR or Cardiovascular CT. The article describes the methods and problems of viability assessment in 18FDG PET study. PET imaging has proved its accuracy and reproducibility for myocardial ischemia and viability assessment. However this unique in its ability for showing the particular substrate metabolism technique has unfortunately some disadvantages: currently achieved PET resolution is 0.4 cm. However the combined devices multislice computed tomography scanners with PET (PET/CT) are now widely used in clinical practice. This combination allows for wider morphologic assessments: coronary calcium scoring and non-invasive coronary angiography may be added to myocardial perfusion/metabolic imaging if necessary. PMID:23047574

Kobylecka, Ma?gorzata; M?czewska, Joanna; Fronczewska-Wieniawska, Katarzyna; Mazurek, Tomasz; P?azi?ska, Maria Teresa; Królicki, Leszek

2012-04-24

251

Does ex vivo vascular resistance reflect viability of non–heart-beating donor livers?  

Microsoft Academic Search

AimsThe use of non–heart-beating (NHB) donor livers is limited by a higher risk for primary nonfunction and the absence of methods to measure this risk. This study was designed to determine whether ex vivo vascular resistance of livers correlates with the length of warm ischemia (WI), and, thus, with viability of NHB livers.

K. Derveaux; D. Monbaliu; T. Crabbé; D. Schein; J. Brassil; D. Kravitz; J. Fevery; L. Jacobbi; T. Roskams; J. Pirenne

2005-01-01

252

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...

253

Effects of Decontamination Methods and Culture Conditions on Viability of Mycobacterium ulcerans in the BACTEC System  

Microsoft Academic Search

We used the BACTEC system to evaluate the effects of several decontamination methods and the addition of antibiotics on the viability of Mycobacterium ulcerans. The effects of polyoxyethylene stearate or egg yolk as supplements were also evaluated to determine their impact on the growth of M. ulcerans. Strains of different geographic origins were subjected to Petroff, reversed Petroff, oxalic acid,

J. C. PALOMINO; F. PORTAELS

254

Studies of In Vitro Activities of Voriconazole and Itraconazole against Aspergillus Hyphae Using Viability Staining  

Microsoft Academic Search

The minimal fungicidal concentrations (MFCs) of voriconazole and itraconazole for five clinical isolates each of Aspergillus terreus, Aspergillus fumigatus, Aspergillus flavus, and Aspergillus niger were determined by a broth macrodilution method. Conidial suspensions as inocula were compared to hyphae as inocula since the invasive form of aspergillosis is manifested by the appearance of hyphal structures. In addition, cell viability staining

CORNELIA LASS-FLORL; MARKUS NAGL; CORNELIA SPETH; HANNO ULMER; MANFRED P. DIERICH; REINHARD WURZNER

2001-01-01

255

Cryopreservation time does not decrease follicular viability in ovarian tissue frozen for fertility preservation  

PubMed Central

OBJECTIVE: To determine the effect of storage duration on cryopreserved ovarian tissue using fresh and frozen-thawed samples. METHODS: Seventeen fertile patients underwent an ovarian biopsy during elective laparoscopic tubal ligation. The tissue sample was divided into three parts: one part was processed fresh (FG), and two were slowly frozen, cryopreserved for 30 (G30) or 180 days (G180), thawed and analyzed. Follicular density, follicular viability, and steroidogenic capacity were assessed. RESULTS: We observed no differences between the groups in follicular density, which was assessed in hematoxylin and eosin–stained tissue sections. A heterogeneous follicular distribution was observed in the parenchyma, with a mean density of 361.3±255.4, 454.9±676.3, and 296.8±269.0 follicles/mm3 for FG, G30 and G180, respectively (p?=?0.46). Follicular viability was greater in FG (93.4%) when compared with the cryopreserved tissues (70.8% for G30 (p<0.001) and 78.4% for G180 (p<0.001)), with no difference in viability between the frozen samples (p>0.05). The steroidogenic capacity of the tissue was not significantly reduced following cryopreservation. CONCLUSION: The slow freezing procedures used for ovarian cryopreservation are capable of preserving follicular viability and maintaining the steroidogenic capacity of the tissue despite a roughly 30% decrease in follicular viability. Furthermore, short-term storage of ovarian tissue does not appear to compromise follicle integrity.

Campos, Jacira Ribeiro; Rosa-e-Silva, Julio Cesar; Carvalho, Bruno Ramalho; Vireque, Alessandra Aparecida; Silva-de-Sa, Marcos Felipe; de Sa Rosa-e-Silva, Ana Carolina Japur

2011-01-01

256

Economic Sanctions  

NSDL National Science Digital Library

Provided by the Institute for International Economics (IIE) (reviewed in the December 4, 1997 Scout Report for Business & Economics), this site is a useful resource for Economics or International Relations courses. Using testimony, speeches, articles, working papers, and an interesting case study (of Myanmar), the site explains and explores the economic and political goals and impact of sanctions. Additional Hot Topics features include the Japan Crisis, the Asian Financial Crisis, and the Euro Conversion.

1999-01-01

257

Introducing Economics.  

ERIC Educational Resources Information Center

The booklet outlines and presents examples of basic economics concepts. Objectives are to help elementary and secondary teachers introduce economic concepts in the classroom and to help teachers grasp some of the fundamentals of economics. The document is divided into seven sections. Each section presents concepts, offers three supporting…

Federal Reserve Bank of Boston, MA.

258

Stimulating Economics  

ERIC Educational Resources Information Center

|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…

Banaian, King

2009-01-01

259

Behavioral Economics  

Microsoft Academic Search

Behavioral economics uses evidence from psychology and other disciplines to create models of limits on rationality, willpower and self-interest, and explo re their implications in economic aggregates. This paper reviews the basic themes of behavioral economics: S ensitivity of revealed preferences to descriptions of goods and procedures; generalizations of models of choice over risk, ambiguity, and time; fairness and recip

Colin F. Camerer

260

Stimulating Economics  

ERIC Educational Resources Information Center

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…

Banaian, King

2009-01-01

261

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

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.

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

262

Financial viability, medical technology, and hospital closures.  

PubMed

Informed investments in medical technology and information systems are associated with the financial viability of community hospitals. Financially distressed facilities are 3 to 4 years behind proactive hospitals in supporting high-speed data, voice, and image transmissions to physicians in various locations. Impact of the Balanced Budget Act of 1997, fraud and abuse activities, Y2K issues, and lack of information systems support for physicians will result in 800 hospital closures and mergers of distressed hospitals over the next 60 months. These findings are based on the application of an eight-step framework for classifying information systems in health care entities. This framework is validated by survey instruments, site visits, interviews with senior management in 44 health care entities containing 576 hospitals, and judgments on the financial status of the health care entities. PMID:10845382

Prince, T R; Sullivan, J A

2000-01-01

263

Magnetic resonance imaging for myocardial viability.  

PubMed

Detection of myocardial viability is an important issue that needs to be addressed when patients with dysfunctional myocardium are considered to be revascularised. The pathophysiological substrate may include myocardial hibernation, myocardial stunning, or both. The greatest benefit is in terms of myocardial function recovery and prognosis is obtained if the revascularised vascular territory contains viable myocardium. Viable myocardium can be detected with nuclear techniques (SPECT, PET), low dose dobutamine stress echocardiography and MRI. With MRI robust detection of viable myocardium can be performed with delayed enhancement (with gadolinium contrast agent), low dose dobutamine stress, and stress/rest perfusion imaging. For recovery of myocardial function there are relatively small differences between all available techniques, whereas for improvement of prognosis all techniques perform equally. Myocardial delayed enhancement imaging can also visualise micro-embolisation as a result of percutaneous coronary intervention. Furthermore, MRI delayed enhancement enables differentiation between ischaemic and non-ischaemic heart disease and can identify specific cardiomyopathies. PMID:20542816

Siebelink, Hans-Marc J; Lamb, Hildo J

2010-05-01

264

Evaluation of myocardial viability with cardiac magnetic resonance imaging.  

PubMed

Assessment of myocardial viability is of clinical and scientific significance. Traditionally, the detection of myocardial viability (either stunning or hibernation) has been used in aiding diagnosis before revascularization, especially in high-risk patients. There is a considerable body of observational evidence showing substantial improvement after revascularization in patients with significant left ventricular dysfunction and myocardial viability. Recent randomized evidence has questioned the benefit of viability testing but must be interpreted with caution. Dobutamine stress echocardiography, nuclear imaging, and cardiovascular magnetic resonance are the mainstays of viability testing and provide information on contractile function, cellular metabolism, and myocardial fibrosis, respectively. Larger, multicenter trials with outcome data are needed to define the nature of viability testing and, particularly, cardiovascular magnetic resonance in moderate-to-severe ischemic cardiomyopathy. PMID:22014488

Grover, Suchi; Srinivasan, Govindarajan; Selvanayagam, Joseph B

265

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

SciTech Connect

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.

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

2004-08-30

266

Socio-Economic and Health Access Determinants of Breast and Cervical Cancer Screening in Low-Income Countries: Analysis of the World Health Survey  

PubMed Central

Background Breast and Cervical cancer are the two most common cancers among women in developing countries. Regular screening is the most effective way of ensuring that these cancers are detected at early stages; however few studies have assessed factors that predict cancer screening in developing countries. Purpose To assess the influence of household socio-economic status (SES), healthcare access and country level characteristics on breast and cervical cancer screening among women in developing countries. Methods Women ages 18–69 years (cervical cancer screening) and 40–69 years (breast cancer screening) from 15 developing countries who participated in the 2003 World Health Survey provided data for this study. Household SES and healthcare access was assessed based on self-reported survey responses. SAS survey procedures (SAS, Version 9.2) were used to assess determinants of breast and cervical cancer screening in separate models. Results 4.1% of women ages 18–69 years had received cervical cancer screening in the past three years, while only 2.2% of women ages 40–69 years had received breast cancer screening in the past 5 years in developing countries. Cancer screening rates varied by country; cervical cancer screening ranged from 1.1% in Bangladesh to 57.6% in Congo and breast cancer screening ranged from 0% in Mali to 26% in Congo. Significant determinants of cancer screening were household SES, rural residence, country health expenditure (as a percent of GDP) as well as healthcare access. Discussion A lot more needs to be done to improve screening rates for breast and cervical cancer in developing countries, such as increasing health expenditure (especially in rural areas), applying the increased funds towards the provision of more, better educated health providers as well as improved infrastructure.

Akinyemiju, Tomi F.

2012-01-01

267

Property Rights and Economic Development  

Microsoft Academic Search

This chapter develops a unified analytical framework, drawing on and extending the existing literature on the subject, for studying the role of property rights in economic development. It addresses two fundamental and related questions concerning the relationship between property rights and economic activity. (i) What are the mechanisms through which property rights affect economic activity? (ii) What are the determinants

Timothy Besley; Maitreesh Ghatak

2010-01-01

268

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  

Microsoft Academic Search

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

M. Downing; R. L. Graham

1993-01-01

269

Rapid flow cytometric method for the assessment of toxic dinoflagellate cyst viability.  

PubMed

The inadvertent transfer and dispersal of non-indigenous marine species via shipping ballast water is of increasing environmental concern. Despite a major global effort to develop new ballast water treatment technologies, their acceptance has been hampered by the lack of suitable indicator species for assessing treatment effectiveness. Resistant dinoflagellate cysts are one proposed test organism, however their use has been limited due to difficulties in assessing their viability after treatment. The paper describes the development of a rapid method to determine the viability of cysts of the dinoflagellate Alexandrium catenella using staining with SYTOX Green and flow-cytometric analysis. The viability of A. catenella cysts was inversely proportional to their ability to take up the stain. There was excellent agreement between cysts measured as viable/non-viable using flow cytometry and cyst viability determined in standard long-term germination tests. Advantages of the flow-cytometric method include high test precision and rapid testing times of < 2 days, compared to > 4 weeks using existing germination methods. PMID:16740303

Binet, M T; Stauber, J L

2006-04-18

270

Viability of Trichomonas vaginalis in Urine: Epidemiologic and Clinical Implications?  

PubMed Central

The impact of the viability of Trichomonas vaginalis in urine on wet mount, culture, and PCR methods was assessed. To minimize the chance of false-negative results, urine specimens should be processed within 30 min of specimen collection and maintained at 37°C, since temperature appears to affect the viability of Trichomonas.

Shafir, Shira C.; Sorvillo, Frank J.

2006-01-01

271

Assessing the viability of tiger subpopulations in a fragmented landscape  

Microsoft Academic Search

Summary 1. Conservation managers require accurate and timely information on the occurrence, size and viability of populations, but this is often difficult for cryptic species living at low densities over large areas. This study aimed to provide such information for tigers in the 36 400-km 2 Kerinci Seblat (KS) region, Sumatra, by identifying and assessing subpopu- lation viability under different

MATTHEW LINKIE; GUILLAUME CHAPRON; DEBORAH J. MARTYR; JEREMY HOLDEN; NIGEL LEADER-WILLIAMS

2006-01-01

272

Ingredient Supplementation Effects on Viability of Probiotic Bacteria in Yogurt  

Microsoft Academic Search

The present investigation studied the effects of cysteine, whey powder, whey protein concentrate, acid casein hydrolysates, or tryptone on the viability of Streptococcus thermophilus, Lactobacillus acidophi- lus, and bifidobacteria. Changes in pH, titratable acidity, redox potential, and viability of bacteria were monitored during 24 h of fermentation and refriger- ated storage ( 4°C) of yogurt for 35 d. The incubation

R. I. Dave; N. P. Shah

1998-01-01

273

Human cell viability to laser pulse and ion transport processes  

NASA Astrophysics Data System (ADS)

We have studied experimentally the problem of cell viability during laser-tissue interaction: how the cell viability can be regulated under certain laser regime. Many modern laser therapeutic techniques assume that cells should survive laser therapy or even to become activated (laser stimulation of immune system). An influence of ion balance was studied for human Red Blood Cells (RBC) during in vitro measurements of single RBC viability after laser pulse. Single cell viability was measured optically with Laser Viability Test which is based upon interpretation of cell photothermal response to pump pulse (532 nm, 10 ns, 10 - 50 (mu) J at 12 micrometer diameter). According to our experiments laser-induced cell damage occurs at different laser energy levels within one cell population (heterogeneity of cell viability) and besides is donor-dependent. The latter result means that laser therapeutic dose should be adjusted individually. For solutions of the ions Na+, K+, Ca++ and Mg++ we have found strong dependence of cell viability upon the process of ion transport through the cell membrane which was regulated by variation of concentration and composition of above mentioned ions. An increase of Na+ or K+ concentration causes a decrease of RBC laser viability.

Lapotko, Dmitry; Romanovskaya, Tat'yana

2000-06-01

274

Microbial engineering strategies to improve cell viability for biochemical production.  

PubMed

Efficient production of biochemicals using engineered microbes as whole-cell biocatalysts requires robust cell viability. Robust viability leads to high productivity and improved bioprocesses by allowing repeated cell recycling. However, cell viability is negatively affected by a plethora of stresses, namely chemical toxicity and metabolic imbalances, primarily resulting from bio-synthesis pathways. Chemical toxicity is caused by substrates, intermediates, products, and/or by-products, and these compounds often interfere with important metabolic processes and damage cellular infrastructures such as cell membrane, leading to poor cell viability. Further, stresses on engineered cells are accentuated by metabolic imbalances, which are generated by heavy metabolic resource consumption due to enzyme overexpression, redistribution of metabolic fluxes, and impaired intracellular redox state by co-factor imbalance. To address these challenges, herein, we discuss a range of key microbial engineering strategies, substantiated by recent advances, to improve cell viability for commercially sustainable production of biochemicals from renewable resources. PMID:23403071

Lo, Tat-Ming; Teo, Wei Suong; Ling, Hua; Chen, Binbin; Kang, Aram; Chang, Matthew Wook

2013-02-10

275

Economic Feasibility of Import Substitution of Livestock Feed in the Caribbean Community.  

National Technical Information Service (NTIS)

Widespread use of import substitution (replacing imported with domestic goods) in the Caribbean Community (CARICOM) makes CARICOM an ideal focus for evaluating the viability of this strategy. This study examines the economic feasibility of import substitu...

C. F. Charles D. Blandford R. N. Boisvert

1980-01-01

276

Marketing Economics  

Microsoft Academic Search

This note helps prepare the student for a series of exercises in making calculations of marketing economics. These calculations are not replacements for spreadsheets or more detailed economic calculations such as net present value or return on investment. They are "back-of-the-envelope" estimates that can easily be communicated to others to buttress arguments about what a company should or should not

Paul Farris; Ron Mentus; Richard Johnson; Ronald Wilcox; Marian Moore

277

Behavioral Economics  

Microsoft Academic Search

Behavioral Economics is the combination of psychology and economics that investigates what happens in markets in which some of the agents display human limitations and complications. We begin with a preliminary question about relevance. Does some combination of market forces, learning and evolution render these human qualities irrelevant? No. Because of limits of arbitrage less than perfect agents survive and

Sendhil Mullainathan; Richard H. Thaler

2000-01-01

278

A bacteriophage detection tool for viability assessment of Salmonella cells.  

PubMed

Salmonellosis, one of the most common food and water-borne diseases, has a major global health and economic impact. Salmonella cells present high infection rates, persistence over inauspicious conditions and the potential to preserve virulence in dormant states when cells are viable but non-culturable (VBNC). These facts are challenging for current detection methods. Culture methods lack the capacity to detect VBNC cells, while biomolecular methods (e.g. DNA- or protein-based) hardly distinguish between dead innocuous cells and their viable lethal counterparts. This work presents and validates a novel bacteriophage (phage)-based microbial detection tool to detect and assess Salmonella viability. Salmonella Enteritidis cells in a VBNC physiological state were evaluated by cell culture, flow-cytometry and epifluorescence microscopy, and further assayed with a biosensor platform. Free PVP-SE1 phages in solution showed the ability to recognize VBNC cells, with no lysis induction, in contrast to the minor recognition of heat-killed cells. This ability was confirmed for immobilized phages on gold surfaces, where the phage detection signal follows the same trend of the concentration of viable plus VBNC cells in the sample. The phage probe was then tested in a magnetoresistive biosensor platform allowing the quantitative detection and discrimination of viable and VBNC cells from dead cells, with high sensitivity. Signals arising from 3 to 4 cells per sensor were recorded. In comparison to a polyclonal antibody that does not distinguish viable from dead cells, the phage selectivity in cell recognition minimizes false-negative and false-positive results often associated with most detection methods. PMID:24055938

Fernandes, E; Martins, V C; Nóbrega, C; Carvalho, C M; Cardoso, F A; Cardoso, S; Dias, J; Deng, D; Kluskens, L D; Freitas, P P; Azeredo, J

2013-09-07

279

[In vitro viability and glutathione levels in mesencephalic neurons after seven days hibernation].  

PubMed

In embryonic mesencephalic transplant in patients with Parkinson s disease dopaminergic survival is low (5 10%), and for this reason the use of multiple donors has been considered. The difficulty of obtaining more tissue determines the need for a procedure that enables human nigral tissue to be stored for a time without affecting its physiological state in any significant way. This study was designed to determine whether hibernation of tissue fragments has any influence on viability, how the viability of the mesencephalic cells behaves after 7 days hibernation and the glutathione levels in the hibernated tissue (HT). The viability of the HT in pieces (82.37 2.12) was found to be higher than the value for the whole mesencephalon (70.29 3.43). Viability of the HT, seven days at 4 C, at different post dissociation times, did not differ significantly. Despite the significant differences found between hibernated and fresh tissue at t= 0, this procedure does not seem to affect the mesencephalic tissue in any significant way, as it conserved a 94% viability after hibernation. No evidence was found of increased glutathione content as an antioxidizing response to the damage that might be caused by hibernation. These results suggest that since hibernation does not have any significant effect on the state of the cells it could be considered a useful procedure for conserving tissue to be used in clinical transplants. Moreover, further research is needed on survival and functionality of hibernated cells after being transplanted into animal models in order to evaluate their potential for use in cell therapy. PMID:12134300

De La Cuétara-Bernal, K; Castillo-Díaz, L; Cruz-Aguado, R; González-Mena, Y; García-Varona, A Y

280

Assessment of tissue viability by polarization spectroscopy  

NASA Astrophysics Data System (ADS)

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.

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

2008-09-01

281

Viability and functional integrity of washed platelets  

SciTech Connect

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.

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

1989-07-01

282

The effect of 2.1 T static magnetic field on astrocyte viability and morphology.  

PubMed

The viability and a number of morphological properties of in situ astrocytes of rat spinal cord cultures including changes in surface area and migration of both cell body and nucleus were investigated at magnetic field intensities comparable to those currently used for magnetic resonance imaging. Viability of rat spinal astrocytes was studied after up to 72 hours of 2.1T static magnetic field exposure. Surface areas and two-dimensional centroids of both soma and nucleus after 2 hours of magnetic field exposure were determined and compared with those of the same cells before magnetic field exposure. Cell membrane ruffling was quantified using fractal analysis. Viability of astrocytes remained unchanged at 4, 16, 24, 48 and 72 hours. The mean soma area before and after 2 hours of field exposure was 6450 microm(2) and 6299 microm(2), respectively, whereas the values for nuclear area were 185.6 microm(2) and 185.7 microm(2). The mean displacement of the centroid of soma parallel and perpendicular to the magnetic field direction was 1.07 microm and 0.78 microm, respectively. The corresponding quantities for nuclei were 0.29 microm and -2.00 microm. None of these changes were statistically significant. No membrane protrusion was observed by fractal analysis. In conclusion, strong static magnetic field at 2.1 T does not significantly affect the viability and morphological properties of rat astrocytes. PMID:20456893

Khodarahmi, Iman; Mobasheri, Hamid; Firouzi, Masoumeh

2010-04-24

283

Effects of fat preparation methods on the viabilities of autologous fat grafts.  

PubMed

Fat grafts are commonly used in plastic surgery, but their unpredictable absorption rates are a considerable disadvantage. Furthermore, no agreement has been reached regarding the method that best enables fat graft survival. This study aimed to evaluate the effects of different preparation methods on fat graft viability. Fat tissue was harvested from the remnants of transverse rectus abdominis musculocutaneous (TRAM) flaps by syringe aspiration. Harvested fat tissue was prepared using three different methods: centrifugation, metal sieve concentration, and cotton gauze concentration. To evaluate the viabilities of fat cells, XTT assays were performed. For the study, 18 nude mice were allocated to three groups: the centrifugation, metal sieve, and cotton gauze groups (6 mice per group). Prepared fat (1 ml) was injected into the nuchal area of the mice, and 12 weeks later, grafts were dissected to determine graft survival rates and subjected to histologic analysis. No significant differences were observed in graft survival rates and histologic findings (necrosis and vascularity) between the three groups. However, histologic analysis found the metal sieve group to have significantly lower fat cell viability and more inflammation than the other two groups. The findings suggest that the closed centrifugation technique has no advantage over the open cotton gauze technique in terms of fat graft viability, and that the metal sieve concentration method is deficient as a preparation method because it can cause grafted fat degradation. PMID:20442997

Minn, Kyung-Won; Min, Kyung-Hee; Chang, Hak; Kim, Sukwha; Heo, Eun-Ju

2010-05-05

284

ECONOMIC SYSTEMS  

NSDL National Science Digital Library

The information you will explore is: List and categorize the four main types of Economic Systems in our world today. Create graphic Illustrations of thoughts and concepts. Express how economic system structures effect the lives of the people living in that system. Write to express an opinion or point of view. Experience a simulation of the marketplace. Research a country of your choice and find important factors about their economic system. Each country structures their economic system after one of the four main types or a combination of these. The assignments on this page will help you to gain a better understanding of the characteristics of the four main types of economic systems. Process: 1. Click on the following link Marketing Calendar Open the Global Economy power point. Use the Chapter 4 listening guide with the power point. chap4 listening guide 2. List the four main economic systems and find the main characterisitics of each. Compare strengths and weaknesses of each. Economic Systems Characteristics 3.Create a ...

Mrs.owen

2006-10-10

285

Phenoxybenzamine treatment can lead to loss of endothelial cell viability.  

PubMed

Phenoxybenzamine, an irreversible alpha-adrenoceptor antagonist, is used as a topical treatment against catecholamine-induced contraction in radial artery bypass grafts. Published data suggest that a wide range of phenoxybenzamine doses may be equally effective. This study aimed to investigate whether lower doses of phenoxybenzamine would benefit grafts by better preserving endothelium. To this end human vascular endothelial cells were isolated from sections of radial artery or saphenous vein, and treated with phenoxybenzamine for 30 min. Cells were then washed free of drug and viability assayed using a resazurin-based toxicology assay or returned to culture for assay at 24 h. Phenoxybenzamine treatment showed a dose-dependent effect on cell viability over several clinically employed concentrations. Concentrations above 0.1 mM led to a loss of viability, which became more pronounced with time. The loss of viability was shown to be independent of the carrier used, as results were identical when phenoxybenzamine was dissolved in dimethylsulphoxide, which alone did not affect viability. Changes in pH alone were also not sufficient to affect viability. In conclusion, phenoxybenzamine treatment is likely to cause damage to graft endothelium if employed at concentrations above 0.1 mM (0.03 mg/ml). Phenoxybenzamine may be safely used at lower doses with no potential loss of endothelial cell viability. PMID:18573847

Pai, Krishnanand R; Conant, Alan R; Browning, Paul G; Dihmis, Walid C

2008-06-23

286

Resource Economics  

NASA Astrophysics Data System (ADS)

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. Through these examples and additional exercises at the end of each chapter, 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.

Conrad, Jon M.

1999-10-01

287

Market Myths in Contemporary Economics  

Microsoft Academic Search

This paper elaborates on the economic operating system (EOS) the role it can play in growth. It focuses on markets, price determination and forces of demand and supply in order to illustrate how an EOS model offers greater economic growth, stability and safety. It delves into market theory to determine whether what is commonly understood about market forces and free

Siize Punabantu

2010-01-01

288

Cell viability monitoring using Fano resonance in gold nanoslit array  

NASA Astrophysics Data System (ADS)

Cell viability is a crucial issue in biological research. We present label-free monitoring of adhesion cells viability by gold nanoslits-based Fano resonance biosensors. Plastic multiple wells with gold nanoslits substrate were made using a thermal nanoimprint method. Adhesion cells in the wells were treated with doxorubicin for inducing cell death and compared with conventional colorimetric assay. The nanoslits method shows better respones of viability tests under low concentration and short interaction time due to its high surface sensitivies. The vinculin labelling indicates that the measured signals are in good agreement with the adhesion abilities of cells.

Wu, Shu-Han; Hsieh, Shu-Yi; Lee, Kuang-Li; Weng, Ruei-Hung; Chiou, Arthur; Wei, Pei-Kuen

2013-09-01

289

Single-cell analysis of cell viability after a biocide treatment unveils an absence of positive correlation between two commonly used viability markers  

PubMed Central

Discrimination among viable/active or dead/inactive cells in a microbial community is a vital question to address issues on ecological microbiology or microbiological quality control. It is commonly assumed that metabolically active cells (ChemchromeV6 [CV6] procedure) correspond to viable cells (direct viable count procedure [DVC]), although this assumption has never been demonstrated and is therefore a matter of debate. Indeed, simultaneous determination of cell viability and metabolic activity has never been performed on the same cells. Here, we developed a microfluidic device to investigate the viability and the metabolic activity of Escherichia coli cells at single-cell level. Cells were immobilized in a flow chamber in which different solutions were sequentially injected according to different scenarios. By using time-lapse microscopy combined with automated tracking procedures, we first successfully assessed the ability of cells to divide and their metabolic activity at single-cell level. Applying these two procedures on the same cells after a hypochlorous acid (HOCl) treatment, we showed that the ability of cells to divide and their metabolic activity were anticorrelated. These results indicate that the relation between CV6 uptake and cell viability may be partially incorrect. Care must be taken in using the terms “CV6-positive” and “viable” synonymously.

Ducret, Adrien; Dukan, Sam

2013-01-01

290

Economic Indicators  

NSDL National Science Digital Library

Both scholars and those with a penchant for statistics will want to bookmark this fine website created and maintained by the federal government. The site provides monthly compilations of economic indicators covering prices, wages, production, business activity, purchasing power, credit, money, and Federal finance. Visitors can use the search engine to type in their desired terms, or they can browse every month from January 1998 forward via a series of drop down tabs. For those who might be looking for more specific data, the "Search Tips" feature is quite useful. The site also contains links to the Federal Reserve Archival System for Economic Research (FRASER), which contains economic indicators back to 1948. Overall, the site will be a real boon to those looking for high quality, accurate information regarding current and past economic trends and patterns in the United States.

291

Economic History  

Microsoft Academic Search

\\u000a The history of a region or people encompasses a multitude of aspects of social life: culture, religion, political institutions,\\u000a social movements, environmental change, technology, population—and the circumstances and processes of economic change that\\u000a the region undergoes. One does not need to be a reductionist in order to observe that the economic circumstances a society\\u000a experiences, and the processes of change

Daniel Little

292

Behavioral economics  

PubMed Central

Economics, like behavioral psychology, is a science of behavior, albeit highly organized human behavior. The value of economic concepts for behavioral psychology rests on (1) their empirical validity when tested in the laboratory with individual subjects and (2) their uniqueness when compared to established behavioral concepts. Several fundamental concepts are introduced and illustrated by reference to experimental data: open and closed economies, elastic and inelastic demand, and substitution versus complementarity. Changes in absolute response rate are analyzed in relation to elasticity and intensity of demand. The economic concepts of substitution and complementarity are related to traditional behavioral studies of choice and to the matching relation. The economic approach has many implications for the future of behavioral research and theory. In general, economic concepts are grounded on a dynamic view of reinforcement. The closed-economy methodology extends the generality of behavioral principles to situations in which response rate and obtained rate of reinforcement are interdependent. Analysis of results in terms of elasticity and intensity of demand promises to provide a more direct method for characterizing the effects of “motivational” variables. Future studies of choice should arrange heterogeneous reinforcers with varying elasticities, use closed economies, and modulate scarcity or income. The economic analysis can be extended to the study of performances that involve subtle discriminations or skilled movements that vary in accuracy or quality as opposed to rate or quantity, and thus permit examination of time/accuracy trade-offs.

Hursh, Steven R.

1984-01-01

293

Effect of Cadmium on Cellular Viability in Two Species of Microalgae ( Scenedesmus sp. and Dunaliella viridis )  

Microsoft Academic Search

We determined the effect of several concentrations of cadmium (0, 5, 10, and 20 ?g\\/l) on cellular viability in the microalgae\\u000a Scenedesmus sp. and Dunaliella viridis, by measuring growth at 0, 24, 48, 72, and 96 h and pigment production at 10 days. Algae were obtained from the Nonvascular\\u000a Plant Laboratory collection, in the Facultad Experimental de Ciencias, Universidad del Zulia, Venezuela. Growth

Letty Beatriz C. Marcano; Ingrid M. Carruyo; Xiomara M. Montiel; Carolina B. Morales; Patricia Moreno de Soto

2009-01-01

294

Viability and permeability across Caco-2 cells of CBZ solubilized in fully dilutable microemulsions  

Microsoft Academic Search

The purpose of this study was to evaluate the viability and permeability of carbamazepine (CBZ) solubilized in fully dilutable non-ionic microemulsions across Caco-2 cells used as a model for intestinal epithelium. Maximum solubilization capacity (SC) of CBZ was determined within water-in-oil (W\\/O), bicontinuous and oil-in-water (O\\/W) structures formed upon dilution. The effect of the nature of the oil phase, surfactant

Anna Kogan; Ellina Kesselman; Dganit Danino; Abraham Aserin; Nissim Garti

2008-01-01

295

Influence of storage method on the viability, mycelial growth and pathogenicity of Sclerotinia sclerotiorum sclerotia  

Microsoft Academic Search

The effect of three storage methods on the viability, mycelial growth and pathogenicity of Sclerotinia sclerotiorum (isolate S36) sclerotia was determined with a view towards establishing an optimal method for storing this pathogen during\\u000a its mass production as a mycoherbicide for controlling the weed Ranunculus acris. Sclerotia were stored at ?80°C, 4°C after desiccation, or at room temperature after freeze-drying

B. M. Pottinger; H. J. Ridgway; G. W. Bourdôt; A. Stewart

2008-01-01

296

Ovarian fluid mediates the temporal decline in sperm viability in a fish with sperm storage.  

PubMed

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

Gasparini, Clelia; Evans, Jonathan P

2013-05-14

297

37 CFR 1.807 - Viability of deposit.  

Code of Federal Regulations, 2013 CFR

...Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES Biotechnology Invention Disclosures Deposit of Biological Material § 1.807 Viability of deposit. (a) A deposit...

2013-07-01

298

Viability Assay Validation Protocol Telecon, January 23, 2012 ...  

Center for Biologics Evaluation and Research (CBER)

... Q: is this -----b)(4)---- should be a set amount…not a range. Q: protocol states this gives 'very low viability” upon thawing. ... More results from www.fda.gov/biologicsbloodvaccines/cellulargenetherapyproducts/approvedproducts

299

Non-Rail Vehicle Market Viability Study. Executive Summary.  

National Technical Information Service (NTIS)

Currently, only four manufacturers account for most of the transit bus production in the United States. Nevertheless, buses represent the largest single mode of public transportation. In order to investigate the viability of the U.S. transit bus manufactu...

2006-01-01

300

Using the pollen viability and morphology for fluoride pollution biomonitoring.  

PubMed

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. PMID:22161315

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

2011-12-13

301

Tissue viability imaging for quantification of skin erythema and blanching  

NASA Astrophysics Data System (ADS)

Naked eye observation has up to recently been the main method of determining skin erythema (vasodilatation) and blanching (vasoconstriction) in skin testing. Since naked eye observation is a highly subjective and investigatordependent method, it is difficult to attain reproducibility and to compare results reported by different researchers performing their studies at different laboratories. Consequently there is a need for more objective, quantitative and versatile methods in the assessment of alterations in skin erythema and blanching caused by internal and external factors such as the intake of vasoactive drugs, application of agents on the skin surface and by constituents in the environment. Since skin microcirculation is sensitive to applied pressure and heat, such methods should preferably be noninvasive and designed for remote use without touching the skin. As skin microcirculation further possesses substantial spatial variability, imaging techniques are to be preferred before single point measurements. An emerging technology based on polarization digital camera spectroscopy - Tissue Viability Imaging (TiVi) - fulfills these requirements. The principles of TiVi (1) and some of its early applications (2-5) are addressed in this paper.

Nilsson, Gert E.; Leahy, Martin J.

2010-02-01

302

Light exposure and cell viability in fluorescence microscopy.  

PubMed

Test systems for measuring cell viability in optical microscopy (based on colony formation ability or lysosomal integrity) were established and applied to native cells as well as to cells incubated with fluorescence markers or transfected with genes encoding for fluorescent proteins. Human glioblastoma and Chinese hamster ovary cells were irradiated by various light doses, and maximum doses where at least 90% of the cells survived were determined. These tolerable light doses were in the range between 25 J cm?² and about 300 J cm?² for native cells (corresponding to about 250-3000 s of solar irradiance and depending on the wavelength as well as on the mode of illumination, e.g. epi- or total internal reflection illumination) and decreased to values between 50 J cm?² and less than 1 J cm?² upon application of fluorescent markers, fluorescent proteins or photosensitizers. In high-resolution wide field or laser scanning microscopy of single cells, typically 10-20 individual cell layers needed for reconstruction of a 3D image could be recorded with tolerable dose values. Tolerable light doses were also maintained in fluorescence microscopy of larger 3D samples, e.g. cell spheroids exposed to structured illumination, but may be exceeded in super-resolution microscopy based on single molecule detection. PMID:22126439

Schneckenburger, H; Weber, P; Wagner, M; Schickinger, S; Richter, V; Bruns, T; Strauss, W S L; Wittig, R

2011-11-29

303

Decreased winter severity increases viability of a montane frog population.  

PubMed

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

McCaffery, Rebecca M; Maxell, Bryce A

2010-04-26

304

The inositol regulon controls viability in Candida glabrata  

PubMed Central

Inositol is essential in eukaryotes, and must be imported or synthesized. Inositol biosynthesis in Saccharomyces cerevisiae is controlled by three non-essential genes that make up the inositol regulon: ScINO2 and ScINO4, which together encode a heterodimeric transcriptional activator, and ScOPI1, which encodes a transcriptional repressor. ScOpi1p inhibits the ScIno2-ScIno4p activator in response to extracellular inositol levels. An important gene controlled by the inositol regulon is ScINO1, which encodes inositol-3-phosphate synthase, a key enzyme in inositol biosynthesis. In the pathogenic yeast Candida albicans, homologues of the S. cerevisiae inositol regulon genes are ‘transcriptionally rewired’. Instead of regulating the CaINO1 gene, CaINO2 and CaINO4 regulate ribosomal genes. Another Candida species that is a prevalent cause of infections is Candida glabrata; however, C. glabrata is phylogenetically more closely related to S. cerevisiae than C. albicans. Experiments were designed to determine if C. glabrata homologues of the inositol regulon genes function similarly to S. cerevisiae or are transcriptionally rewired. CgINO2, CgINO4 and CgOPI1 regulate CgINO1 in a manner similar to that observed in S. cerevisiae. However, unlike in S. cerevisiae, CgOPI1 is essential. Genetic data indicate that CgOPI1 is a repressor that affects viability by regulating activation of a target of the inositol regulon.

Bethea, Emily K.; Carver, Billy J.; Montedonico, Anthony E.; Reynolds, Todd B.

2010-01-01

305

Sperm viability staining in ecology and evolution: potential pitfalls  

Microsoft Academic Search

The causes and consequences of variation in sperm quality, survival and ageing are active areas of research in ecology and\\u000a evolution. In order to address these topics, many recent studies have measured sperm viability using fluorescent staining.\\u000a Although sperm viability staining has produced a number of interesting results, it has some potential pitfalls that have rarely\\u000a been discussed. In the

Luke Holman

2009-01-01

306

Bacterial plasmolysis as a physical indicator of viability  

Microsoft Academic Search

Bacterial plasmolytic response to osmotic stress was evaluated as a physical indicator of membrane integrity and hence cellular viability. Digital image analysis and either low-magnification dark-field, high-magnification phase-contrast, or confocal laser microscopy, in conjunction with pulse application of a 1.5 NaCl solution, were used as a rapid, growth-independent method for quantifying the viability of attached biofilm bacteria. Bacteria were considered

D. R. Korber; A. Choi; G. M. Wolfaardt; D. E. Caldwell

1996-01-01

307

Neonatal Ethical Issues: Viability, Advance Directives, Family-Centered Care.  

PubMed

Ethical issues in perinatal and NICU settings can arise from a variety of situations. This article focuses on issues surrounding viability and the incorporation of advance directives and family-centered care. Prenatal education about infant viability, probable scenarios, and parental involvement in decisionmaking are addressed. Considerations for advance directives for complex births and critical decisions at the time of birth are also discussed. Implications for nurses and suggested dialogue strategies are provided. PMID:21407121

Sudia-Robinson, Tanya

2011-03-14

308

Multimodality imaging in the assessment of myocardial viability  

Microsoft Academic Search

The prevalence of heart failure due to coronary artery disease continues to increase, and it portends a worse prognosis than\\u000a non-ischemic cardiomyopathy. Revascularization improves prognosis in these high-risk patients who have evidence of viability;\\u000a therefore, optimal assessment of myocardial viability remains essential. Multiple imaging modalities exist for differentiating\\u000a viable myocardium from scar in territories with contractile dysfunction. Given the multiple

Sara L. Partington; Raymond Y. Kwong; Sharmila Dorbala

2011-01-01

309

On the Relations Between Politics and Economics  

Microsoft Academic Search

The Marxist viewpoint concerning the relationship between politics and economics is a development of the historical materialist doctrine on the relations between the productive forces and production relations and between the economic base and the superstructure in the real life. According to the theory of historical materialism, economics determines politics, and politics in turn reacts on economics. The Wang, Zhang,

Lin Zili; You Lin

1979-01-01

310

Honesty and trust in economic relationships  

Microsoft Academic Search

Trust is not a homogeneous phenomenon. In economic relationships different trust structures are at work, including distrust, negative trust and lack of trust. Perceived honesty and competence co-determine the trust structures economic agents have in their interactions with others. Trust structures influence the way agents engage in economic relationships. Honesty and competence should be developed to improve trust in economic

Laszlo Zsolnai

2004-01-01

311

Technical and economic feasibility of telerobotic on-orbit satellite servicing  

NASA Astrophysics Data System (ADS)

The aim of this research is to devise an improved method for evaluating the technical and economic feasibility of telerobotic on-orbit satellite servicing scenarios. Past, present, and future telerobotic on-orbit servicing systems and their key capabilities are examined. Previous technical and economic analyses of satellite servicing are reviewed and evaluated. The standard method employed by previous feasibility studies is extended, developing a new servicing decision approach incorporating operational uncertainties (launch, docking, et cetera). Comprehensive databases of satellite characteristics and on-orbit failures are developed to provide input to the expected value evaluation of the servicing versus no-servicing decision. Past satellite failures are reviewed and analyzed, including the economic impact of those satellite failures. Opportunities for spacecraft life extension are also determined. Servicing markets of various types are identified and detailed using the results of the database analysis and the new, expected-value-based servicing feasibility method. This expected value market assessment provides a standard basis for satellite servicing decision-making for any proposed servicing architecture. Finally, the method is demonstrated by evaluating a proposed small, lightweight servicer providing retirement services for geosynchronous spacecraft. An additional benefit of the method is that it enables parametric analysis of the sensitivity of economic viability to the probability of docking success, thus establishing a threshold for that critical value. While based on a more economically conservative approach, the new method demonstrates the feasibility of the proposed server in the face of operational uncertainties.

Sullivan, Brook Rowland

312

Viable cell yield from active dry yeast products and effects of storage temperature and diluent on yeast cell viability.  

PubMed

Active dry yeast (ADY) products are commonly fed in the dairy industry, but research regarding quality control for such products is limited. The objectives of this study were to determine yeast viability in field samples relative to manufacturers' guarantees (experiment 1), measure the effects of high-temperature storage on yeast viability (experiment 1), and determine the effect of vitamin-trace mineral (VTM) premix on yeast viability (experiment 2). Commercially available ADY products were acquired in triplicate through normal distribution channels and stored at 4°C upon receipt. Initial samples were evaluated for colony-forming units and compared with product label guarantees. Only 1 of the 6 products sampled in experiment 1 met product guarantees for all 3 samples. To determine effects of storage temperature and duration on viability, ADY samples were stored in an incubator at 40°C with ambient humidity for 1, 2, and 3 mo. High-temperature storage significantly decreased viability over the 3-mo period; approximately 90% of viable cells were lost each month. Three of the 5 products sampled in experiment 2 met product guarantees. Fresh samples of 4 of these 5 ADY products were mixed in duplicate with ground corn (GC) or a VTM premix to achieve a target concentration of 2.2×10(8) cfu/g. For each product, GC and VTM samples were stored at ambient temperature (22°C) and at an elevated temperature (40°C) for 2 wk. No differences in viable yeast count were observed between GC and VTM samples immediately after mixing or after storage at ambient temperature. Yeast viability in GC and VTM samples decreased during storage at an elevated temperature. There also was a significant interaction of diluent and storage temperature; VTM samples had higher cell viability than GC samples when subjected to high-temperature storage. Results suggest that (1) ADY products failed to consistently meet product guarantees; (2) viability of ADY products was greatly diminished during storage at 40°C for 2 wk; and (3) the loss in viability at elevated temperatures may be attenuated when ADY products are diluted with a premix containing VTM. PMID:21183066

Sullivan, M L; Bradford, B J

2011-01-01

313

AIDS Economics  

NSDL National Science Digital Library

UNAIDS (The Joint United Nations Programme on HIV/AIDS) and the World Bank worked together to create the AIDS Economics site to help improve understanding of the economics of HIV/AIDS and to "help researchers and policymakers in developing countries to define and implement humane, cost-effective policies to fight the disease." The highlight of the site is the summary of the findings and statistical appendices from Confronting AIDS: Public Priorities in a Global Epidemic, a World Bank report. The full text of the report will be available shortly. The site also features a toolkit to assist consultants in assessing the implications of HIV/AIDS in the distribution of development assistance. Visitors to the site can also sign up for AIDS Economics, a free electronic newsletter.

1998-01-01

314

An Economic Approach to Business Ethics: Moral Agency of the Firm and the Enabling and Constraining Effects of Economic Institutions and Interactions in a Market Economy  

Microsoft Academic Search

The paper maps out an alternative to a behavioural (economic) approach to business ethics. Special attention is paid to the fundamental philosophical principle that any moral ‘ought’ implies a practical ‘can’, which the paper interprets with regard to the economic viability of moral agency of the firm under the conditions of the market economy, in particular competition. The paper details

Sigmund Wagner-Tsukamoto

2005-01-01

315

[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

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. PMID:24001653

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

2013-05-01

316

Assessment of the viability of skin grafts  

SciTech Connect

A number of tests are available to monitor the blood flow in free and distant pedicle skin grafts. The information from these tests aids in the development of measures to enhance vascularization and is occasionally needed to make clinical decisions in patients with distant pedicle grafts. Measurements of the disappearance of an intradermally injected small amount of /sup 133/Xe allows determination of a clearance rate and blood flow before and after clamping the original blood supply through the base. With /sup 99m/Tc, which is generally more readily available, a flow index and block index can be determined. Clinically both procedures give equally good results in determining a safe time for pedicle base separation. The fluorescein test allows assessment of regional blood flow distribution within the pedicle.

Wahner, H.W.

1988-07-01

317

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

PubMed

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. PMID:20435763

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

2010-04-30

318

Effect of octenidine dihydrochloride on viability of protoscoleces in hepatic and pulmonary hydatid diseases.  

PubMed Central

BACKGROUND: Use of effective scolicidal agents during puncture, aspiration or injection of a scolicidal agent and reaspiration (PAIR) and surgery for hydatid cysts are essential to reduce the recurrence rate. In this in vitro study, we tried to determine the scolicidal property of a new agent, octenidine dihydrochloride, and of various agents in different concentrations and exposure times. MATERIAL AND METHODS: Echinococcus granulosus protoscoleces were obtained from six patients with liver (n=3) and lung (n=3) hydatid cysts. Various concentrations of octenidine dihydrochloride (0.1%, 0.01% and 0.001% diluted form), povidone iodine (10%, 1% and 0.1% diluted) and 20% saline were used in this study. Viability of protoscoleces was determined with dye-uptake (0.1% eosin) and flame cell activity. RESULTS: Octenidine dihydrochloride 0.1% had strong scolicidal effect in 15 min and octenidine dihydrochloride 0.01% in 30 min. Sixty percent of protoscoleces lost viability at 5 min with octenidine dihydrochloride 0.1%. Viability ratio decreased to 20% at 10 min, and all of them died at 15 min. Povidone iodine 10% and 1% had strong scolicidal effects after 15- and 30 min of exposure, respectively. Saline 20% killed all the protoscoleces in 30-min exposure. CONCLUSION: Because of the rapid and strong scolocidal effectiveness of octenidine dihydrochloride on protoscoleces, it may be used as a scolocidal agent during both perioperative and in the PAIR method.

Ciftci, Ihsan Hakki; Esme, Hidir; Sahin, Dursun Ali; Solak, Okan; Sezer, Murat; Dilek, Osman Nuri

2007-01-01

319

How to assess intestinal viability during surgery: A review of techniques  

PubMed Central

Objective and quantitative intraoperative methods of bowel viability assessment are essential in gastrointestinal surgery. Exact determination of the borderline of the viable bowel with the help of an objective test could result in a decrease of postoperative ischemic complications. An accurate, reproducible and cost effective method is desirable in every operating theater dealing with abdominal operations. Numerous techniques assessing various parameters of intestinal viability are described by the studies. However, there is no consensus about their clinical use. To evaluate the available methods, a systematic search of the English literature was performed. Virtues and drawbacks of the techniques and possibilities of clinical application are reviewed. Valuable parameters related to postoperative intestinal anastomotic or stoma complications are analyzed. Important issues in the measurement and interpretation of bowel viability are discussed. To date, only a few methods are applicable in surgical practice. Further studies are needed to determine the limiting values of intestinal tissue oxygenation and flow indicative of ischemic complications and to standardize the methods.

Urbanavicius, Linas; Pattyn, Piet; Van de Putte, Dirk; Venskutonis, Donatas

2011-01-01

320

New Device for High-Throughput Viability Screening of Flow Biofilms ?  

PubMed Central

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.

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

2010-01-01

321

Assessment of losses in honey yield due to the chalkbrood disease, with reference to the determination of its economic injury levels in Egypt.  

PubMed

In Egypt, the chalk brood (CHB) disease caused by the fungus, Ascosphaera apis Maassen started again infesting the honeybee, Apis melifera L (Hymenoptera: Apidae) colonies after a cessation pause of seven to nine years. For the first time, an attempt has been made to look into the problem of the CHB disease from the view point of assessing losses in both clover (Trifolium alexandrinum) and chinus (Chinus molus) honey yields. In this regard, two techniques were adopted. Under the natural conditions of the experimental apiary (first technique), loss in clover honey was 18.412 +/- 0.663%, on average, whereas the average loss in chinus honey was 18.332 +/- 1.536%. In the second technique of loss appraisal (artificial infection). The tested honeybee colonies were artificially infected with four sources of A. apis infection, I.e. black mummies, white mummies, pollen grains and water, in addition to controls to create the so-called "different levels of infection". The mean percentages of losses in clover honey were 30.06 +/- 1.807, 27.95 +/- 1.062; 21.13 +/- 0.987; 16.96 +/- 0.672 and 0.00 +/- 0.00 for black mummies, white mummies, pollen grains, water and control, respectively. Taking into account the relationship between number of resulted mummies in each source of infection and % loss in clover honey, it could be concluded that as the resulted mummies increased, the corresponding clover honey yield decreased in each source of infection. It was noticed that the % loss in clover honey differed as the used technique differed. For example, the percentage loss in clover honey produced from colonies exposed to the natural conditions was relatively less than that of the artificially infected ones. This has been discussed in the text. However, the causative pathogen of CHB disease resulted in serious decrease in honey production. Loss appraisal is a perquisite step for the determination of the economic injury levels (EILs). By regressing % loss in clover honey yield against the total number of fallen mummies, the linear equation was worked out to be: Y = 0.242 + 0.040 x (r2 = 0.99, F = 62408.865). Depending on the total costs of controlling CHB disease, the EIL values were 31.875 and 11.250 mummies/colony for cedar oil and thymol granules, subsequently. As to the chinus honey the corresponding EILs were 18.940 and 6.683 mummies/colony for cedar oil and thymol granules, in respect, as a result of adopting the regression formula: Y = -6.762 + 0.101 X. As for the clover honey (artificial infection) the EIL values were 39.844 and 14.063 mummies/ colony in case of using cedar oil and thymol grains, subsequently. These values were worked out using the formula Y = 5.871 + 0.032 X. From the practical point of view, apiarists should not use thymol or cedar oil as fallen mummies don't reach the suggested EILs values to minimize control costs as much as possible. PMID:16628907

Zaghloul, O A; Mourad, A K; El Kady, Magda B; Nemat, F M; Morsy, M E

2005-01-01

322

The mouse dead-end gene isoform ? is necessary for germ cell and embryonic viability  

PubMed Central

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 ? (DND1- ?) and DND1-isoform ? (DND1-?). Using isoform specific antibodies, we determined DND1-? is expressed in embryos and embryonic gonads whereas DND1-? expression is restricted to germ cells of the adult testis. Our data implicates DND1-? 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.

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

2007-01-01

323

Economics of productivity and farm structure: A comparison of organic and conventional dairy farms in the United States  

Microsoft Academic Search

This dissertation broadens and deepens the understanding of the economics of organic dairy farming by applying economic theory of the firm, modern econometric methods, and the first large-scale, representative sample of organic dairy farms in the United States. With national standards for organic production only recently established in 2002, little is known about the productivity and economic viability of organic

Carlos David Mayen Solorzano

2009-01-01

324

ECONOMIC SANCTIONS AND CULTURE  

Microsoft Academic Search

We address empirically the question of why international economic sanctions are, or are not, chosen as instruments of foreign policy and the question of what determines their success. We hypothesize that cultural linkages between nations are an important factor in explaining both instrument choice and conflict outcomes. Countries that share significant cultural attributes are found to be less likely to

Donna Driscoll; Dennis Halcoussis; Anton D. Lowenberg

2010-01-01

325

ECONOMIC SANCTIONS AND CULTURE  

Microsoft Academic Search

We address empirically the question of why international economic sanctions are, or are not, chosen as instruments of foreign policy and the question of what determines their success. We hypothesize that cultural linkages between nations are an important factor in explaining both instrument choice and conflict outcomes. Countries that share significant cultural attributes are found to be less likely to

Donna Driscoll; Dennis Halcoussis; Anton D. Lowenberg

2011-01-01

326

INNOVATIVE ECONOMIC DEVELOPMENT  

Microsoft Academic Search

Communities faced with the challenge of attracting and retaining industrial and commercial businesses to increase economic development can increase their effectiveness and decision making processes through the use of GIS and 3D visualization. The ability to communicate visually proposed plans for developments, determine the potential visual impact on surrounding areas, and educate the public about how these proposed developments appear

Robert Montgomery

327

Crime and Economic Incentives  

ERIC Educational Resources Information Center

|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.|

Machin, Stephen; Meghir, Costas

2004-01-01

328

Home Economics.  

ERIC Educational Resources Information Center

|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…

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

329

Resource Economics  

NASA Astrophysics Data System (ADS)

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

Conrad, Jon M.

2000-01-01

330

Economic Blues  

ERIC Educational Resources Information Center

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…

Stuart, Reginald

2009-01-01

331

Economic & commercial viability of hydrogen fuel cell vehicles from an automotive manufacturer perspective  

Microsoft Academic Search

Ford Motor Company's experience with Fuel Cell Vehicle (FCV) technology began over ten years ago with the P2000 concept. Development of this vehicle demonstrated technological feasibility of, and revealed a number of challenges to, automotive fuel cell commercialization. By 2005, Ford launched the Focus FCV fleet in partnership with the U.S. Department of Energy, Fuel Cells Canada (now Hydrogen and

Greg Frenette; Daniel Forthoffer

2009-01-01

332

Economic viability of NaS battery plant in a competitive electricity market  

Microsoft Academic Search

Unlike markets for storable commodities, electricity markets depend on the real-time balance of supply and demand. Although much of the present-day grid operate effectively without storage technologies, cost-effective ways of storing electrical energy can make the grid more efficient and reliable. One of the emerging electric energy storage technologies is NaS (Natrium Sulfur) battery system. Recently, this technology is strongly

S. Jalal Kazempour; Mohsen Parsa Moghaddam

2009-01-01

333

Economic viability of small nuclear reactors in future European cogeneration markets  

Microsoft Academic Search

Small nuclear reactors align well with the small heat-capacity needs for many European process industries. Combined heat and power (CHP) reactors can support the EU low-carbon society goals while providing stability in production and cost. High temperature reactor technologies are well suited for the production of “high value†heat by producing temperatures of 200–550°C. However, little is known about the

Johan Carlsson; David E. Shropshire; Aliki van Heek

2012-01-01

334

Rapid and economical high-performance liquid chromatographic method for the determination of norfloxacin in serum using a microparticulate C 18 guard cartridge  

Microsoft Academic Search

A rapid and economical high-performance liquid chromatographic assay is described for norfloxacin in serum. Samples (100 ?l) containing N-ethylnorfloxacin as the internal standard were extracted into 1 ml of chloroform. Chromatography was performed at 30°C on a 40×3.2 mm I.D. C18 guard cartridge (3 ?m spherical particles) using a mobile phase of 11% (v\\/v) acetonitrile in 0.01 M phosphate buffer

Steven C. Wallis; Bruce G. Charles; Lawrence R. Gahan

1995-01-01

335

[Economic crime].  

PubMed

Economic crime, often also referred to as white collar crime, is one of the most incidious and predatory of offenses. Unlike street crime, for which there may well be some protection, the average citizen is completely at the mercy of the perpetrators of economic crimes. The concept of white collar crime was first identified by Edwin H. Sutherland. He dealt with the problem as a violation of trust involving either or both misrepresentation and duplicity. He argued for the use of criminal sanctions rather than civil remedies as a means of dealing with white collar offenses. Sutherland's views were attacked by the legal profession, by sociologists and criminologists and by public opinion specialists. They contended that an act treated in civil court is not a crime; that criminals are those persons who are defined as such and white collar criminals are neither so defined nor do they define themselves as criminals and, finally, that economic crime is universal. Can anyone be criminal, then, ask the critics? A number of studies by Clinard, Quinney, Black, Ball, Cressey, Newman and others have translated the interest in white collar crime into empirical terms. The last thirty-five years have also witnessed the elaboration and alteration of the theory itself. Geis' work has been particularly important in this respect. His "street" versus "suite" crime is a useful dichotomy. Most important, however, have been the monograph and papers by Herbert Edelhertz who has conceptualized the issues on various levels - from consumer fraud to the illegal activities of the multinational corporation. This article is concerned with the exposition of the theory and research in the field. Most significant, the paper raises serious doubts whether the problem of economic crime can be researched and studied; it raises even more difficult issues concerning the legal and sociological implications of economic crime and of its prevention, management and control. PMID:1030807

Dinitz, S

336

Viability study of photo-voltaic systems added to terrestrial electric vehicles  

SciTech Connect

The purpose of the following computer study is to determine the set of necessary conditions under which the addition of photo-voltaic (PV) cells to electric vehicles provides a net utility or economic benefit. Economic benefits are given the primary focus and are evaluated in terms of a payback period.

Rippel, W.E.

1990-09-01

337

Economic Analysis of Effluent Guidelines: The Textiles, Friction and Sealing Materials Segment of the Asbestos Manufacturing Industry.  

National Technical Information Service (NTIS)

This report estimates the broad economic effects (including product price increases, continued viability of affected plants, employment, industry growth and foreign trade) of the required application of various control technologies.

S. V. Margolin B. U. N. Igwe

1975-01-01

338

Goals Study for Technical Development and Economic Evaluation of the Compound Parabolic Concentrator Concept for Solar Energy Collector Applications.  

National Technical Information Service (NTIS)

The Argonne National Laboratories, contracted with Arthur D. Little, Inc. (ADL), to perform a 6 week goal study for the purpose of evaluating the technical applicability and the economic viability of the compound parabolic concentrator (CPC) concept for a...

1975-01-01

339

Emerging national space launch programs: Economics and safeguards  

Microsoft Academic Search

Most ballistic missile nonproliferation studies have focused on trends in the numbers and performance of missiles and the resulting security threats. This report concentrates on the economic viability of emerging national space launch programs and the prospects for imposing effective safeguards against the use of space launch technology for military missiles. For the convenience of discussion in this report, a

Brian G. Chow

1993-01-01

340

Argument Schemes and Critical Questions for Heterogeneous Agents to Argue Over the Viability of a Human Organ for Transplantation  

Microsoft Academic Search

In this paper we present a framework in which heterogeneous agents can argue over the viability of a human organ for transplantation. This collaborative decision making process among human and\\/or software agents is mediated by a soft- ware agent that uses argument schemes and critical questions to direct the deliberation, and determines a final evaluation of the given arguments. The

Pancho Tolchinsky; Sanjay Modgil; Ulises Cortes

341

Myocardial Viability Testing and the Effect of Early Intervention in Patients With Advanced Left Ventricular Systolic Dysfunction  

Microsoft Academic Search

Background—The clinical value of revascularization and other procedures in patients with severe systolic heart failure is unclear. It has been suggested that assessing ischemia and viability by positron emission tomography (PET) with fluorodeoxyglucose (FDG) imaging may identify patients for whom revascularization may lead to improved survival. We performed a propensity analysis to determine whether there might be a survival advantage

Khaldoun G. Tarakji; Richard Brunken; Patrick M. McCarthy; M. Obadah Al-Chekakie; Ahmed Abdel-Latif; Claire E. Pothier; Eugene H. Blackstone; Michael S. Lauer

2010-01-01

342

Myocardial Viability: What We Knew and What Is New  

PubMed Central

Some patients with chronic ischemic left ventricular dysfunction have shown significant improvements of contractility with favorable long-term prognosis after revascularization. Several imaging techniques are available for the assessment of viable myocardium, based on the detection of preserved perfusion, preserved glucose metabolism, intact cell membrane and mitochondria, and presence of contractile reserve. Nuclear cardiology techniques, dobutamine echocardiography and positron emission tomography are used to assess myocardial viability. In recent years, new advances have improved methods of detecting myocardial viability. This paper summarizes the pathophysiology, methods, and impact of detection of myocardial viability, concentrating on recent advances in such methods. We reviewed the literature using search engines MIDLINE, SCOUPS, and EMBASE from 1988 to February 2012. We used key words: myocardial viability, hibernation, stunning, and ischemic cardiomyopathy. Recent studies showed that the presence of viable myocardium was associated with a greater likelihood of survival in patients with coronary artery disease and LV dysfunction, but the assessment of myocardial viability did not identify patients with survival benefit from revascularization, as compared with medical therapy alone. This topic is still debatable and needs more evidence.

Shabana, Adel; El-Menyar, Ayman

2012-01-01

343

Effects of cartilage impact with and without fracture on chondrocyte viability and the release of inflammatory markers.  

PubMed

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. To further investigate chondrocyte response to impact and fracture, we 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-?B) activity in Toll-like receptor (TLR) -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-?B 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 and the potential for post-injury inflammation. PMID:23620164

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

2013-04-25

344

Effect of HUVEC apoptosis inducing proteinase from Vipera lebetina venom (VLAIP) on viability of cancer cells and on platelet aggregation.  

PubMed

Three cancer cell lines, the human androgen independent prostate cancer PC-3, androgen dependent LNCaP prostate cancer and human chronic myeloid leukaemia cell line K-562, were treated with Sephadex G-100 sf fractions of Vipera lebetina venom and with HUVEC apoptosis inducing heterodimeric metalloproteinase (VLAIP) from the same venom. The venom was separated into nine fractions using size-exclusion chromatography on Sephadex G-100 sf. The effect of V. lebetina venom gel filtration fractions on the viability of studied cancer cells was different: high molecular mass fractions were the most effective on PC-3 cells. The viability of LNCaP cells was inhibited most strongly by the third fraction. The first and the second fractions contain different metalloproteinases including VLAIP that also most effectively reduced the viability of PC-3 cells. VLAIP decreased PC-3 cell viability in a concentration- and time-dependent manner but did not induce apoptosis as shown by DNA fragmentation assay. VLAIP induced changes in cell shape, rounding up and detachment. VLAIP inhibited the PC-3 cell adhesion to extracellular matrix proteins collagen I, fibronectin and vitronectin but not to fibrinogen. VLAIP had no significant effect on the viability of LNCaP and K-562 cells. VLAIP was also capable to inhibit ADP- and collagen-induced platelet aggregation dose-dependently. IC(50) was determined to be 1.89 ?M and 0.94 ?M, respectively. PMID:22781133

Samel, Mari; Trummal, Katrin; Siigur, Ene; Siigur, Jüri

2012-04-09

345

Human sperm DNA oxidation, motility and viability in the presence of L-carnitine during in vitro incubation and centrifugation.  

PubMed

In vitro incubation and centrifugation is known to decrease human sperm quality. In the human body, besides its antioxidant effects, L-carnitine (LC) facilitates the transport of activated fatty acids from the cytosol to the mitochondrial matrix. In this study, we investigated the effect of LC on human sperm motility, viability and DNA oxidation after incubation and centrifugation, following the sperm preparation protocols of assisted reproduction. Normozoospermic semen samples (n = 55) were analysed according to the World Health Organization (WHO) guidelines. LC concentrations that are not toxic to spermatozoa as determined by sperm motility and viability were standardised after 2 and 4 h of incubation at 37 °C. Semen samples to which the optimal LC concentrations were added were also centrifuged for 20 min at 300 g and analysed for sperm motility, viability and DNA oxidation. Sperm motility was improved at 0.5 mg ml(-1) LC after incubation and centrifugation with 5 × 10(6) sperm ml(-1). Higher concentration of LC (50 mg ml(-1)) significantly decreased sperm motility and viability. LC did not alter the baseline of sperm DNA oxidation during both incubation and centrifugation. In conclusion, LC may enhance sperm motility following incubation and centrifugation, while it might not affect sperm viability and DNA oxidation. PMID:21950483

Banihani, S; Sharma, R; Bayachou, M; Sabanegh, E; Agarwal, A

2011-09-26

346

America's Economic Way of War  

Microsoft Academic Search

How did economic and financial factors determine how America waged war in the twentieth century? This important new book exposes the influence of economics and finance on the questions of whether the nation should go to war, how wars would be fought, how resources would be mobilized, and the long-term consequences for the American economy. Ranging from the Spanish–American War

Hugh Rockoff

347

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

PubMed

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. PMID:22653866

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

2012-06-01

348

Impedance microflow cytometry for viability studies of microorganisms  

NASA Astrophysics Data System (ADS)

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.

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

2011-02-01

349

COST IMPACT OF ROD CONSOLIDATION ON THE VIABILITY ASSESSMENT DESIGN  

SciTech Connect

The cost impact to the Civilian Radioactive Waste Management System of using rod consolidation is evaluated. Previous work has demonstrated that the fuel rods of two assemblies can be packed into a canister that can fit into the same size space as that used to store a single assembly. The remaining fuel assembly hardware can be compacted into the same size canisters with a ratio of 1 hardware canister per each 6 to 12 assemblies. Transportation casks of the same size as currently available can load twice the number of assemblies by placing the compacted assemblies in the slots currently designed for a single assembly. Waste packages similarly could contain twice the number of assemblies; however, thermal constraints would require considering either a low burnup or cooling. The analysis evaluates the impact of rod consolidation on CRWMS costs for consolidation at prior to transportation and for consolidation at the Monitored Geological Repository surface facility. For this study, no design changes were made to either the transport casks or waste packages. Waste package designs used for the Viability Assessment design were employed but derated to make the thermal limits. A logistics analysis of the waste was performed to determine the number of each waste package with each loading. A review of past rod consolidation experience found cost estimates which range from $10/kgU to $32/kgU. $30/kgU was assumed for rod consolidation costs prior to transportation. Transportation cost savings are about $17/kgU and waste package cost savings are about $21/kgU. The net saving to the system is approximately $500 million if the consolidation is performed prior to transportation. If consolidation were performed at the repository surface facilities, it would cost approximately $15/kgU. No transportation savings would be realized. The net savings for consolidation at the repository site would be about $400 million dollars.

D. Lancaster

1999-03-29

350

Use of partial budgeting to determine the economic benefits of antibiotic treatment of chronic subclinical mastitis caused by Streptococcus uberis or Streptococcus dysgalactiae.  

PubMed

The economic effect of lactational antibiotic treatment of chronic subclinical intramammary infections due to Streptococcus uberis or Streptococcus dysgalactiae was explored by means of partial budgeting. Effects at cow level and herd level were modelled, including prevention of clinical mastitis episodes and the prevention of transmission of infections. Input variables for our deterministic model were derived from literature or based on 2002/2003 dairy prices and farming conditions in The Netherlands. Sensitivity analysis was used to examine the effect of uncertainty around input variables or changes in price estimates. On farms where pathogen transmission was prevented through proper udder health management, 3-d antibiotic treatment during lactation resulted in an average net profit of euro+11.62 over no treatment while 8-d antibiotic treatment had an average negative net result of euro-21.83. Sensitivity analysis showed that profitability depends on the probability of treatment-induced cure, pathogen transmission rates, culling rate, retention pay-off, and costs of antibiotic treatment. Three-day antibiotic treatment of chronic subclinical streptococcal mastitis is economically profitable over a range of input values for cure probabilities, transmission rates and losses due to culling. In contrast, 8-d lactational treatment is only profitable for very valuable animals, on farms where the risk of pathogen transmission is high and/or when the farmer is likely to cull a high percentage of cows with subclinical mastitis. Because bacterial flora, cow characteristics and management differ widely between farms, the economic outcome of lactational treatment of chronic subclinical streptococcal mastitis may be highly farm-dependent. PMID:15747734

Swinkels, Jantijn M; Rooijendijk, Jolanda G A; Zadoks, Ruth N; Hogeveen, Henk

2005-02-01

351

Influence of Waveform on Cell Viability during Ultrasound Exposure  

NASA Astrophysics Data System (ADS)

We examined the role of ultrasound standing waves, and their travelling wave counterparts, on cell viability in an in-vitro insonation apparatus. Furthermore, the effect of distinct waveforms (sine and top-hat) was also explored, together with the role of microbubble presence. Measurements of cell viability in standing wave scenarios demonstrated a relatively higher rate of lysis (63.13+/-10.89% remaining viable) compared with the travelling wave data, where 96.22+/-4.0% remained viable. Significant differences were also seen as a function of waveform, where insonations employing top-hat wave shapes resulted in an average end stage viability of 30.31+/-5.71% compared with 61.94+/-14.28% in the sinusoidal counterparts.

Saliev, Timur; Feril, Loreto B.; McLean, Donald A.; Tachibana, Katsuro; Campbell, Paul A.

2011-09-01

352

Steroid Mechanisms Affecting Yeast Permeability and Viability1  

PubMed Central

A synthetic aza-cholestane amine was found to be rapidly lethal to Saccharomyces cerevisiae. Lethal action was prevented by pretreating cells with 10-3m uranyl nitrate. Sublethal concentrations of the steroid prevented the uptake of glucose and alanine. This demonstrated one means by which the steroid affected cell permeability, limiting the growth of the organism. Decreases in viability were related to increases in 260 and 280 m? absorbing materials. Uranyl protection of viability was found to be related to cellular retention of the ultraviolet-absorbing materials. The steroid, dequadin acetate, and cetyl pyridinium chloride were comparable in lethal action and in causing the leakage of cytoplasmic constituents. Loss of viability and cytoplasmic excretion were detected within minutes after cells were exposed to the steroid. The rate or degree of metabolism of glucose by resting cells did not appear to influence steroid action or the sensitivity of the cells to the steroid.

Smith, Rodney F.; Shay, Donald E.

1966-01-01

353

Multimodality imaging in the assessment of myocardial viability.  

PubMed

The prevalence of heart failure due to coronary artery disease continues to increase, and it portends a worse prognosis than non-ischemic cardiomyopathy. Revascularization improves prognosis in these high-risk patients who have evidence of viability; therefore, optimal assessment of myocardial viability remains essential. Multiple imaging modalities exist for differentiating viable myocardium from scar in territories with contractile dysfunction. Given the multiple modalities available, choosing the best modality for a specific patient can be a daunting task. In this review, the physiology of myocardial hibernation and stunning will be reviewed. All the current methods available for assessing viability including echocardiography, cardiac magnetic resonance imaging, nuclear imaging with single photon emission tomography and positron emission tomography imaging and cardiac computed tomography will be reviewed. The effectiveness of the various techniques will be compared, and the limitations of the current literature will be discussed. PMID:21069458

Partington, Sara L; Kwong, Raymond Y; Dorbala, Sharmila

2011-07-01

354

Managerial Economics  

NSDL National Science Digital Library

This Principles of Macroeconomics course page was developed by Robert Forsythe, Associate Professor of Economics at University of Iowa. The course introduces students to basic concepts in macroeconomics such as GDP, inflation and interest rates. Visitors to the site can either view the lecture notes in slide form or listen to lectures via RealAudio. Exams and quizzes (including answers) are also available at the site.

1997-01-01

355

Economic Consequences  

Microsoft Academic Search

\\u000a The economic impacts of computer crimes involving malicious code attacks, unauthorized intrusion into networks and computer\\u000a systems, denial of service of attacks, and others are substantial. In testifying before the Senate Select Committee on Intelligence\\u000a on 6 February 2002, Dale L. Watson, Executive Assistant Director, Counter-terrorism and Counterintelligence of the FBI, pointed\\u000a out that during the past several years the

Michael Erbschloe

356

Integrated economics  

SciTech Connect

This article offers ideas for evaluating integrated solid waste management systems through the use of a conceptual cost overview. The topics of the article include the integrated solid waste management system; making assumptions about community characteristics, waste generation rates, waste collection responsibility, integrated system components, sizing and economic life of system facilities, system implementation schedule, facility ownership, and system administration; integrated system costs; integrated system revenues; system financing; cost projections; and making decisions.

Bratton, T.J. (Gershman, Brickner and Bratton Inc., Falls Church, VA (United States))

1992-09-01

357

Shopbot Economics  

Microsoft Academic Search

Shopbots are agents that search the Internet for information pertaining to the price and quality of goods or services. With\\u000a the advent of shopbots, a dramatic reduction in search costs is imminent, which promises (or threatens) to radically alter\\u000a market behavior. This research includes the proposal and theoretical analysis of a simple economic model which is intended\\u000a to capture some

Jeffrey O. Kephart; Amy R. Greenwald

2002-01-01

358

Economic Feasibility of Commercial Algae Oil Production in the United States  

Microsoft Academic Search

A Monte Carlo simulation model was constructed to analyze the economic feasibility of growing algae as a renewable fuel source. Increasing growth rates, pond water depth, oil content, and facility size are important for ensuring the economic viability of a commercial algae facility.

Bart L. Fischer; James W. Richardson; Joe L. Outlaw; Marc S. Allison

2011-01-01

359

The Economics of Canola Production by Limited-Resource Farmers in South Carolina  

Microsoft Academic Search

The purpose of this study is to examine the economic viability of canola production as an additional or alternative crop for limited-resource fanners in South Carolina, and to investigate the economics of its production as a competing rapeseed and oil crop. Canola offers farmers an additional or alternative crop to fall-planted crops such as winter wheat. Canola seed is in

Emmanuel N. Onunkwo; Natasha W. Holston

1997-01-01

360

Is Online News an Inferior Good? Examining the Economic Nature of Online News among Users  

Microsoft Academic Search

The U.S. newspaper industry is transitioning from print to online, but users' response to online news has fallen short of expectations and thus raised questions about the economic viability of the new medium. This study explores the economic concept of “inferior goods” and its applicability to online news consumption. Analysis of Pew Research Center survey data shows that as income

Hsiang Iris Chyi; Mengchieh Jacie Yang

2009-01-01

361

Assessment of economic and ecological carrying capacity of agricultural crops in Nicaragua  

Microsoft Academic Search

The relationships between, and usefulness of, three different analysis methods: (1) economic cost and return estimation (CAR), (2) ecological footprint (EF) and (3) emergy analysis (EA) in assessing economic viability, ecological carrying capacity and sustainability in tropical crop production was the focus for this study. The analyses were conducted on six agricultural crop production systems in Nicaragua: common bean (Phaseolus

M. Cuadra; J. Björklund

2007-01-01

362

Adhesion to and viability of Listeria monocytogenes on food contact surfaces.  

PubMed

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. PMID:18680936

Silva, Sónia; Teixeira, Pilar; Oliveira, Rosario; Azeredo, Joana

2008-07-01

363

Pollen Viability, Pistil Receptivity, and Embryo Development in Hybridization of Nelumbo nucifera Gaertn  

PubMed Central

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.

Wang, Yan-Li; Guan, Zhi-Yong; Chen, Fa-Di; Fang, Wei-Min; Teng, Nian-Jun

2012-01-01

364

Lack of effect of the ghrelin gene-derived peptide obestatin on cardiomyocyte viability and metabolism.  

PubMed

Obestatin is a recently discovered peptide encoded by the ghrelin gene that opposes ghrelin effects on food intake and gastrointestinal function. The biological activity of obestatin depends on amidation at its carboxyl terminus and on its postulated binding to the orphan G protein-coupled receptor 39 (GPR39). We have previously demonstrated that ghrelin is synthesized by cardiomyocytes and has direct effects on its viability. Our aim was to know if obestatin, derived from the same gene as ghrelin, also affects cardiomyocyte physiology. By RT-PCR and immunocytochemistry we have demonstrated that murine cardiomyocytes cultured in vitro and human atrial tissue express GPR39 receptor. Competitive binding studies with radioiodine 125I-labeled obestatin recognized specific binding sites for this peptide in the murine cardiomyocyte cell line HL-1. However, obestatin did not modify the cell cycle or viability of these cells, and it was not able to prevent the cytosine arabinoside-induced apoptosis of HL-1 cardiomyocytes, as assessed by Hoechst dye vital staining, flow cytometry analysis and determination of lactate dehydrogenase in the culture media. Finally, treatment with obestatin did not affect fatty acid or glucose uptake by HL-1 cardiomyocytes. In conclusion, obestatin is not a relevant metabolic or viability modifier for cardiomyocytes. PMID:17646721

Iglesias, M J; Salgado, A; Piñeiro, R; Rodiño, B K; Otero, M F; Grigorian, L; Gallego, R; Diéguez, C; Gualillo, O; González-Juanatey, J R; Lago, F

2007-06-01

365

Comparison of five incubation systems for rat liver slices using functional and viability parameters.  

PubMed

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. PMID:9403776

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

366

In situ assessment of cell viability within biodegradable polylactic acid polymer matrices.  

PubMed

Efforts to expand treatment options for articular cartilage repair have increasingly focussed on the implantation of cell polymer constructs. Primary cells cultured from perichondrium, a chondrogenic tissue, were found to survive in vitro within a biodegradable porous polylactic acid matrix. The novel application of an in situ fluorescent double-stain protocol to cell polymer constructs was supported by increased 3H-thymidine uptake and the ability of cell seeded polylactic acid to form first passage explant cultures. This in situ viability staining technique allowed for rapid determination of cell viability and, in conjunction with confocal microscopy, assessment of cellular distribution within a biodegradable scaffold. Advantages of using this method over histological and electron microscopic analysis include in situ observation, absence of distortion in scaffold architecture due to polymer dissolution and disruption during processing, and obtaining a viability assessment within 30 min. Potential applications of this protocol as a screening tool for laboratory engineered tissues and in the evaluation of cellular injury in natural tissues are discussed. PMID:8590764

Chu, C R; Monosov, A Z; Amiel, D

1995-12-01

367

Improved osteoblast viability in the presence of smaller nanometre dimensioned carbon fibres  

NASA Astrophysics Data System (ADS)

Carbon nanofibres have been proposed as a possible new orthopaedic/dental implant material due to their unique mechanical, electrical, and cytocompatibility properties. Specifically, these fibres have dimensions (diameters ranging between 60 and 200 nm and aspect ratios of about 500) similar to hydroxyapatite crystals and collagen fibres found in bone. More importantly, previous in vitro studies have provided evidence that nanophase ({\\le } 100 nm diameter) carbon fibres enhance osteoblast (the bone-producing cell) function over conventional (>100 nm diameter) carbon fibres and current orthopaedic implant materials such as titanium, Ti6Al4V, and CoCrMo. However, articulating components of orthopaedic implant materials may generate harmful wear debris. To determine, for the first time, the influence of carbon nanofibre wear debris on osteoblast viability, direct contact toxicity studies were performed in the present in vitro study. Not surprisingly, the results from direct-contact toxicity studies over a 24 h time period provided evidence of time- and concentration-dependent cell viability decreases when exposed to carbon nanofibres. Most importantly, the results from this study provided the first evidence that nanophase carbon fibres were less detrimental to osteoblast viability compared to larger diameter conventional carbon fibres. For this reason, this in vitro study provided continuing evidence of the promise of nanophase materials (particularly, carbon nanofibres) in improving orthopaedic implant efficiency.

Price, Rachel L.; Haberstroh, Karen M.; Webster, Thomas J.

2004-08-01

368

Evaluation of myocardial ischemia and viability by noninvasive cardiac imaging.  

PubMed

Noninvasive cardiac imaging plays a central role in the diagnosis of coronary artery disease and cardiomyopathy, as well as in the decision making for therapeutic interventions. Proper assessment of the degree of myocardial ischemia and viability is essential to aid in therapies that may improve patient outcomes. In addition, a wealth of evidence exists on the prognostic value of the information obtained from noninvasive imaging. One must utilize an imaging study or studies in an organized fashion, incorporating the latest scientific evidence, guidelines and appropriateness criteria. This review summarizes the advantages, disadvantages and relevant literature on various imaging modalities currently available for the evaluation of myocardial ischemia and viability. PMID:22149526

Katikireddy, Chandra K; Mann, Noelle; Brown, David; Van Tosh, Andrew; Stergiopoulos, Kathleen

2012-01-01

369

Is viability still viable after the STICH trial?  

PubMed

Stunning and hibernation represent two different forms of tissue viability identifiable in acute coronary syndromes and chronic ischaemic cardiomyopathy, respectively. Functional recovery occurs spontaneously with myocardial stunning, while it generally follows revascularization in case of hibernating myocardium. Low-dose dobutamine stress echocardiography is an accurate modality for identifying myocardial stunning and provides important information on ventricular remodelling after both systemic thrombolysis and primary angioplasty. In patients with conservatively treated infarction, the prognostic significance of viability by dobutamine stress echocardiography correlates with residual pump function. Substantial contractile reserve is predictive of favourable outcome in patients with poor but not in those with preserved or slightly reduced left ventricular function. Non-invasive assessment of coronary flow reserve with transthoracic Doppler echocardiography of the left anterior descending coronary artery allows to distinguish between necrotic and stunned myocardium and predicts ventricular remodelling following primary angioplasty. Resting echocardiographic examination can provide information on hibernating myocardium. In particular, systolic thickening <7 mm, restrictive filling pattern, and high end-systolic volume are predictive of no viability. Compared with nuclear imaging, dobutamine stress echocardiography is more specific for predicting functional recovery, less expensive, more generally available and radiation-free. A large body of evidence collected over the years demonstrates the favourable prognostic impact of revascularizing extensive myocardial territories which are found viable at dobutamine stress echocardiography in patients with ischaemic cardiomyopathy. The prognostic implications of viability-guided revascularization have been clearly established in both diabetic and non-diabetic patients. However, the prognostic value of myocardial viability has been questioned by the results of the STICH trial that did not demonstrate any advantage of survival in the patients with a large extent of myocardial viability undergoing revascularization. Is the end of a paradigm that deeply influenced clinical practice so far or just a neutral result that can be ignored due to the several limitations of study design? In the present review, we will address the main advantages and limitations of ultrasounds for the evaluation of myocardial viability and try to demonstrate that viability is still viable. PMID:22080451

Cortigiani, Lauro; Bigi, Riccardo; Sicari, Rosa

2011-11-11

370

Aptamer-based viability impedimetric sensor for viruses.  

PubMed

The development of aptamer-based viability impedimetric sensor for viruses (AptaVISens-V) is presented. Highly specific DNA aptamers to intact vaccinia virus were selected using cell-SELEX technique and integrated into impedimetric sensors via self-assembly onto a gold microelectrode. Remarkably, this aptasensor is highly selective and can successfully detect viable vaccinia virus particles (down to 60 virions in a microliter) and distinguish them from nonviable viruses in a label-free electrochemical assay format. It also opens a new venue for the development of a variety of viability sensors for detection of many microorganisms and spores. PMID:22303883

Labib, Mahmoud; Zamay, Anna S; Muharemagic, Darija; Chechik, Alexey V; Bell, John C; Berezovski, Maxim V

2012-02-01

371

Economic assessment of biodiesel production from waste frying oils.  

PubMed

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. PMID:20153167

Araujo, Victor Kraemer Wermelinger Sancho; Hamacher, Silvio; Scavarda, Luiz Felipe

2010-02-11

372

The history of economics as economics?  

Microsoft Academic Search

This paper critically evaluates the current decline of the relationship between economics and the history of economics, and proposes a framework called the panorama-cum-scenario model for the practice of the history of economics. Starting with the Hegelian thesis that the history of economics is economics itself, the paper argues that such a relationship is necessary but not sufficient because the

Yuichi Shionoya

2009-01-01

373

Population viability analysis: using a modeling tool to assess the viability of tapir populations in fragmented landscapes.  

PubMed

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. PMID:23253367

Medici, Emília Patrícia; Desbiez, Arnaud Leonard Jean

2012-12-01

374

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

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.

Michael F. Morea

1997-10-24

375

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

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.

Michael F. Morea

1998-04-23

376

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

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.

Michael F. Morea.

1997-04-25

377

Anti-epileptic drugs inhibit viability of synoviocytes in vitro.  

PubMed

Introduction and objective: The hyperplasia of synovial fibroblasts is considered to be essential for the evolution of joint destruction in rheumatoid arthritis (RA). Previously, we reported that anti-rheumatic drugs, both COX inhibitors and disease-modifying anti-rheumatic drugs inhibit proliferation of synoviocytes in vitro. The presented study investigates the effect of anti-epileptic drugs on the viability and proliferation of synovial fibroblasts in vitro. Methods: Experiments were conducted on human synoviocytes derived from an RA patient and rabbit synoviocytes cell line HIG-82. Cell proliferation and viability were assessed by means of BrdU assay and MTT assay, respectively. The IC50 value (the concentration of drug necessary to induce 50% inhibition) together with confidence limits was calculated. Results: Carbamazepine inhibited proliferation of human fibroblasts and viability of HIG-82 with IC 50 values of 86 µM and 82 µM, respectively. Diphenylhydantoin, valproate and phenobarbital inhibited viability of HIG-82 cells with the IC50 values of 110, 500 and 1031 µM, respectively. Conclusion: Based on these findings, it can be suggested that anti-epileptic drugs may have a disease-modifying effect on rheumatoid synovial proliferation. PMID:24069867

Parada-Turska, Jolanta; Nowicka-St??ka, Patrycja; Majdan, Maria; Jab?o?ski, Miros?aw; Turski, Waldemar A; Rzeski, Wojciech

2013-09-20

378

Agile ITQFD and its financial viability: a pilot project approach  

Microsoft Academic Search

Purpose – The purpose of this paper is to explore the feasibility of adopting a pilot project approach for foreseeing the working and financial viability of a technique, named as agile innovative total quality function deployment (agile ITQFD). Design\\/methodology\\/approach – The agile ITQFD technique and its financial accounting system were designed. The implementation study of two pilot projects on agile

S. Vinodh; G. Sundararaj; S. R. Devadasan; S. Rajanayagam; Immanuel Edinbarough

2008-01-01

379

Nuclear power options viability: Oak Ridge National Laboratory's study  

SciTech Connect

Seven criteria, augmented by desired characteristics, were established to assess the viability of nuclear reactors for the timeframe beginning at 2005 for the United States. Earlier nuclear power needs will be filled by LWRs. Several advanced concepts were selected, based on three ground rules, and assessed. It was concluded that there are several acceptable and viable concepts.

Gat, U.; Trauger, D.B.; White, J.D.

1986-01-01

380

The viability of Campylobacter jenuni on refrigerated chicken drumsticks  

Microsoft Academic Search

Radappertized chicken drumsticks were experimentally contaminated with suspensions ofCampylobacterjejuni in two trials. Qualitative analysis on drumsticks with an initial level of contamination of 4.8×103 CFU\\/cm2 showed that viability was retained for at least 10 days of storage at either 9° or ?12°C.

K. Yogasundram; Simon M. Shane

1986-01-01

381

Handicap signalling: when fecundity and viability do not add up  

Microsoft Academic Search

It is widely accepted that a requirement for honest handicap signalling is that higher-quality signallers pay lower marginal costs for advertising. This is a simple, powerful principle, but it is correct only if the fitness effects of fecundity and viability are strictly additive. Additivity would not be expected from most life history models. The general criterion for honest handicap signalling

1998-01-01

382

Analysis of the Competitive Viability of Independent Middle Distillate Marketers.  

National Technical Information Service (NTIS)

The viability of the home heating oil dealer is being threatened by changes in the basic conditions of the middle distillate industry. These changes, which were examined over the study period from 1972 through 1978, are summarized below. (1) The overall n...

1979-01-01

383

Population viability analysis of the Endangered shortnose sturgeon  

Microsoft Academic Search

This study used population viability analysis (PVA) to partition the influences of potential threats to the endangered shortnose sturgeon (Acipenser brevirostrum). A workshop brought together experts to help identify potential threats including groundwater withdrawal, poor water quality, saltwater intrusion, mercury effects, harvest as by-catch, and sedimentation of spawning habitat. During the course of the project, we eliminated some threats and

Yetta Jager; Mark S Bevelhimer; Douglas L. Peterson

2011-01-01

384

Metam sodium reduces viability and infectivity of Eimeria oocysts  

Technology Transfer Automated Retrieval System (TEKTRAN)

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 ...

385

Analysis of the Viability of Umbilical Cord blood Stem Cells  

Microsoft Academic Search

The investigations on sources and viability of stem cells are important as stem cell transplantation has shown promising results in diseases like leukemias and lymphomas. Umbilical cord blood samples were collected in a closed aseptic system. The samples were diluted with phosphate buffered saline, treated with ficol and centrifuged at 15,000 rpm for the recovery of progenitor stem cells.The stem

Sachdeva N; Neelam Sachdeva Reader

2009-01-01

386

Scale of Viability and Minimal Time of Crisis  

Microsoft Academic Search

In this paper, we introduce and study the minimal time of a crisis map which measures the minimal time spent outside a given closed domain of constraints by trajectory solutions of a differential inclusion. The interest of such a notion is basically to tackle simultaneously viability and target issues. The main mathematical result characterizes the epigraph of the crisis map

L. Doyen; P. Saint-Pierre

1997-01-01

387

Assessment of islet cell viability using fluorescent dyes  

Microsoft Academic Search

Summary  A rapid fluorometric method has been developed to evaluate the viability of isolated islet cells. The assay differentiates between viable and nonviable cells by the simultaneous use of the inclusion and exclusion dyes acridine orange and propidium iodide. When viewed by fluorescent microscopy, viable cells fluoresce green, while nonviable cells fluoresce bright red. Although the acridine orange and propidium iodide

H. L. Bank

1987-01-01

388

Viability of stored seed: extension by cathodic protection.  

PubMed

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. PMID:17818626

Pammenter, N W; Adamson, J H; Berjak, P

1974-12-20

389

Flow cytometric analysis of phytoplankton viability in Elkhorn Slough, California  

Microsoft Academic Search

The phytoplankton community structure of Elkhorn Slough was characterized flow cytometrically and found to be dominated in the upper reaches by small cryptophytes (< 5 microm) and picoeukaryotic phytoplankton (< 3 microm). Cell-specific viability of the small cryptophyte population was quantified along a 5 km transect from the mouth to the shallow upper reaches of Elkhorn Slough using fluorescein diacetate

Sarah Rose Smith

2009-01-01

390

A Measurement of Financial Viability Among Private Colleges.  

ERIC Educational Resources Information Center

|The financial viability of private colleges was assessed by examining the relationship of expenditures to endowment to voluntary support (nongovernment gifts and grants). A sample of 284 private coeducational colleges was drawn from the Council for Financial Aid to Education's (CFAE) annual survey of voluntary support (1976-1977 to 1980-1981).…

Bolda, Phillip J.; Mack, Bruce A.

391

Population viability analyses on a cycling population: a cautionary tale  

Microsoft Academic Search

Population viability analysis (PVA) packages do not always allow realistic simulation of particular life cycle features, so they may produce unrealistic predictions of extinction risk. This was suspected for a cycling Soay sheep population, Ovis aries L., that grows, overeats its habitat and then suffers high winter mortality. We compared projections of PVA models for the sheep that incorporated either

Andrew P. Chapman; Barry W. Brook; Tim H. Clutton-Brock; Bryan T. Grenfell; Richard Frankham

2001-01-01

392

SVM Viability Controller Active Learning: Application to Bike Control  

Microsoft Academic Search

It was shown recently that SVMs are particularly adequate to define action policies to keep a dynamical system inside a given constraint set (in the framework of viability theory). However, the training set of the SVMs face the dimensionality curse, because it is based on a regular grid of the state space. In this paper, we propose an active learning

Laetitia Chapel; G. Deffuant

2007-01-01

393

Impact of release dynamics of laser-irradiated polymer micropallets on the viability of selected adherent cells.  

PubMed

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 optimal operating conditions for laser microbeam-based pallet release systems for the isolation and selection of adherent cells. PMID:22158840

Ma, Huan; Mismar, Wael; Wang, Yuli; Small, Donald W; Ras, Mat; Allbritton, Nancy L; Sims, Christopher E; Venugopalan, Vasan

2011-12-07

394

Aspirin Blocks EGF-stimulated Cell Viability in a COX-1 Dependent Manner in Ovarian Cancer Cells  

PubMed Central

Objective: Although aspirin has been associated with a reduction of the risk of cancer when used as a nonsteroidal anti-inflammatory drug, its use to reduce the risk of ovarian cancer is controversial. Ovarian cancer cells usually express high levels of cyclooxygenase-1 (COX)-1. Because aspirin is a rather selective inhibitor of COX-1, the ability of aspirin to reduce the risk of ovarian cancer may be dependent on the level of COX-1 expression in those cells. Furthermore, epidermal growth factor receptor (EGFR) is frequently overexpressed in the malignant phenotype of ovarian cancer leading to increased cell proliferation and survival. Here we investigated if aspirin attenuates EGFR-activated ovarian cancer cell growth in a COX-1 dependent manner. Methods: Cell viability assays and Western blot analyses were used to determine the effect of aspirin on EGF-stimulated cell proliferation. Gene silencing and gene expression techniques were employed to knockdown or to express COX-1, respectively. Results: Aspirin inhibited cell viability induced by EGF in a dose dependent manner in COX-1 positive ovarian cancer cells. On the other hand, aspirin had no effect on cell viability in COX-1 negative ovarian cancer cells. In particular, aspirin decreased phosphorylated Akt and Erk activated by EGF. COX-1 silencing in COX-1 positive cells attenuated the inhibitory effect of aspirin on EGF-stimulated cell viability. Furthermore, we developed a COX-1 expressing cell line (SKCOX-1) by stably transfecting COX-1 expression vector into COX-1 negative SKOV-3 cells. SKCOX-1 cells were more responsive to aspirin when compared to cells transfected with empty vector, and decreased EGF-activated Akt and Erk as well as cell viability. Conclusions: Taken together, aspirin inhibits viability of ovarian cancer cells by blocking phosphorylation of Akt and Erk activated by EGF. Thus it may potentiate the therapeutic efficacy of drugs used to treat COX-1 positive ovarian cancer subsets.

Cho, May; Kabir, Syeda M.; Dong, Yuanlin; Lee, Eunsook; Rice, Valerie Montgomery; Khabele, Dineo; Son, Deok-Soo

2013-01-01

395

Myocardial Viability and Survival in Ischemic Left Ventricular Dysfunction  

PubMed Central

BACKGROUND The assessment of myocardial viability has been used to identify patients with coronary artery disease and left ventricular dysfunction in whom coronary-artery bypass grafting (CABG) will provide a survival benefit. However, the efficacy of this approach is uncertain. METHODS In a substudy of patients with coronary artery disease and left ventricular dysfunction who were enrolled in a randomized trial of medical therapy with or without CABG, we used single-photon-emission computed tomography (SPECT), dobutamine echocardiography, or both to assess myocardial viability on the basis of pre-specified thresholds. RESULTS Among the 1212 patients enrolled in the randomized trial, 601 underwent assessment of myocardial viability. Of these patients, we randomly assigned 298 to receive medical therapy plus CABG and 303 to receive medical therapy alone. A total of 178 of 487 patients with viable myocardium (37%) and 58 of 114 patients without viable myocardium (51%) died (hazard ratio for death among patients with viable myocardium, 0.64; 95% confidence interval [CI], 0.48 to 0.86; P = 0.003). However, after adjustment for other baseline variables, this association with mortality was not significant (P = 0.21). There was no significant interaction between viability status and treatment assignment with respect to mortality (P = 0.53). CONCLUSIONS The presence of viable myocardium was associated with a greater likelihood of survival in patients with coronary artery disease and left ventricular dysfunction, but this relationship was not significant after adjustment for other baseline variables. The assessment of myocardial viability did not identify patients with a differential survival benefit from CABG, as compared with medical therapy alone. (Funded by the National Heart, Lung, and Blood Institute; STICH ClinicalTrials.gov number, NCT00023595.)

Bonow, Robert O.; Maurer, Gerald; Lee, Kerry L.; Holly, Thomas A.; Binkley, Philip F.; Desvigne-Nickens, Patrice; Drozdz, Jaroslaw; Farsky, Pedro S.; Feldman, Arthur M.; Doenst, Torsten; Michler, Robert E.; Berman, Daniel S.; Nicolau, Jose C.; Pellikka, Patricia A.; Wrobel, Krzysztof; Alotti, Nasri; Asch, Federico M.; Favaloro, Liliana E.; She, Lilin; Velazquez, Eric J.; Jones, Robert H.; Panza, Julio A.

2012-01-01

396

Effect of alternative on-site wastewater treatment on the viability and culturability of Salmonella choleraesuis.  

PubMed

The objective of this study was to determine how alternative on-site wastewater treatment systems (i.e. subsurface flow constructed wetlands, intermittent sand filters and intermittent peat filters) affect the viability and culturability of Salmonella choleraesuis (serotype typhimurium, ATCC 23567). Influent was a high strength septic tank effluent (BOD5 240-344 mgL(-1), TN approximately 100 mgL(-1), TP approximately 15 mgL(-1)) at the Natural Resources Research Institute's (NRRI) alternative treatment system test facility in northern Minnesota. Treatment systems were inoculated with cultures of S. choleraesuis for 5-7 consecutive days in summer and winter during 1998-99. After the seeding, outflow samples were taken until Salmonella counts were sustained at background levels. In addition to culture-based enumeration, S. choleraesuis abundances were also measured using fluorescent in situ hybridization (FISH) alone and in combination with the direct viable count method (DVC) to determine if plate counts underestimated total and viable Salmonella abundances and if the Salmonella cell viability changed after passing through the treatment systems. In most cases, total and viable cell abundances in treatment system effluents were several orders of magnitude higher than cultured cell abundances. Our results indicate that the culture-based method underestimated viable concentrations of the model pathogen, S. choleraesuis. Salmonella cell viability decreased in effluents during the summer but increased during the winter. Using a culture-based enumeration method alone to determine removal efficiencies of bacterial indicators and pathogens for wastewater treatment systems may result in artificially high estimates of effective treatment. PMID:15952448

Pundsack, J W; Hicks, R E; Axler, R P

2005-03-01

397

A Qualitative Exploration of the Economic and Social Effects of Microcredit among People Living with HIV/AIDS in Uganda  

PubMed Central

HIV medical care, including antiretroviral therapy (ART), is often successful in restoring physical health and functioning. But in developing countries, HIV medical care is often insufficient to achieve social and economic health, and hence innovative economic support programs are much needed. We conducted semistructured interviews with 30 adults receiving ART and microcredit loans operated by Uganda Cares. Using content analysis, we explored the impact of the microcredit loans on the economic, social, and psychological well-being of respondents. Most respondents indicated that the microcredit loans played a positive role in their lives, helped them to keep their children in school and sustain their families, and improved their self-esteem and status in the community. In addition, we also found significant positive knowledge spill-over and network effects in the program with regard to business management and support. However, more than half of the participants indicated experiencing repayment problems either personally or with other group members due to unexpected emergencies and sickness. These findings highlight that microcredit programs have the potential of being an economic support system for HIV clients trying to reestablish their livelihoods, especially in resource-constrained settings, though more research is needed to determine the overall economic viability of such programs.

Wagner, Glenn; Rana, Yashodhara; Linnemayr, Sebastian; Balya, James; Buzaalirwa, Lydia

2012-01-01

398

A Qualitative Exploration of the Economic and Social Effects of Microcredit among People Living with HIV/AIDS in Uganda.  

PubMed

HIV medical care, including antiretroviral therapy (ART), is often successful in restoring physical health and functioning. But in developing countries, HIV medical care is often insufficient to achieve social and economic health, and hence innovative economic support programs are much needed. We conducted semistructured interviews with 30 adults receiving ART and microcredit loans operated by Uganda Cares. Using content analysis, we explored the impact of the microcredit loans on the economic, social, and psychological well-being of respondents. Most respondents indicated that the microcredit loans played a positive role in their lives, helped them to keep their children in school and sustain their families, and improved their self-esteem and status in the community. In addition, we also found significant positive knowledge spill-over and network effects in the program with regard to business management and support. However, more than half of the participants indicated experiencing repayment problems either personally or with other group members due to unexpected emergencies and sickness. These findings highlight that microcredit programs have the potential of being an economic support system for HIV clients trying to reestablish their livelihoods, especially in resource-constrained settings, though more research is needed to determine the overall economic viability of such programs. PMID:22778923

Wagner, Glenn; Rana, Yashodhara; Linnemayr, Sebastian; Balya, James; Buzaalirwa, Lydia

2012-06-21

399

Forest management and economics  

SciTech Connect

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.

Buongiorno, J.; Gilless, J.K.

1987-01-01

400

Viability and fertilizing capacity of cryopreserved sperm from three North American acipenseriform species: A retrospective study  

USGS Publications Warehouse

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; viability and motility results were correlated, but independent of fertilization. For pallid sturgeon sperm (experiment 4), MT with 5-10% MeOH showed significantly higher sperm quality and fertilization parameters. Membrane integrity can be used as a predictor of fertilization by cryopreserved sperm, however additional sperm quality parameters, supplementary to motility and membrane integrity, would be useful in the refining and optimizing cryopreservation protocols with acipenseriform sperm. ?? 2008 Blackwell Verlag, Berlin.

Horvath, A.; Wayman, W. R.; Dean, J. C.; Urbanyi, B.; Tiersch, T. R.; Mims, S. D.; Johnson, D.; Jenkins, J. A.

2008-01-01

401

Bacterial viability on surface-modified resin-based dental restorative materials.  

PubMed

The purpose of the present investigation was to investigate the viability of early colonizers on the surfaces of resin-based dental restorative materials modified with low-surface tension active agents in comparison with the unmodified material. A novel polymeric sorption material, loaded with two low-surface tension ?(L) active agents (hydroxyfunctional polydimethylsiloxane and polydimethylsiloxane) or a polymerizable active agent (silicone polyether acrylate), was used to modify commonly formulated experimental dental resin composites. The non-modified resin was used as the standard (ST). The viability of Actinomyces naeslundii, Actinomyces viscosus, Streptococcus mitis, Streptococcus oralis, and Streptococcus sanguinis on water-stored, polished, and human saliva pellicle-coated specimens was determined using a fluorescence microscope after 8 and 24h. Total, vital, and non-vital cells were calculated from the microscopic images by counting pixels per colour. Means, standard deviations, univariate ANOVA and multiple comparisons with post hoc Scheffé's tests were calculated. t-Test was done to compare 8-h and 24-h bacteria counts. For all tests p<0.05 was chosen. Null hypothesis: the test materials and the standard did not differ either in the total bacterial counts or in the respective bacterium's viability after 8 or 24h. The test materials modified with the silicone polyether acrylate showed lower total bacteria count after 8 or 24h than ST. But all test materials had significantly fewer vital cells after 8 or 24h compared to ST. The contact angle did not influence bacterial adhesion, but low total SFE and a low polar term of SFE resulted in fewer bacteria. The material's chemistry also affected the total and vital cell counts. Different bacteria viabilities needed to be explored to obtain relevant information regarding bacterial adhesion on dental composite resins. The novel sorption material loaded with low ?(L) active agents or with a low ?(L) polymerizable silicone polyether acrylate used to modify the chemistry of the test materials was appropriate to reduce bacterial adhesion or cell viability, respectively. PMID:22673754

Rüttermann, Stefan; Bergmann, Nora; Beikler, Thomas; Raab, Wolfgang H-M; Janda, Ralf

2012-06-04

402

Religion and Economic Growth across Countries  

Microsoft Academic Search

Empirical research on the determinants of economic growth typically neglects the influence of religion. To fill this gap, this study uses international survey data on religiosity for a broad panel of countries to investigate the effects of church attendance and religious beliefs on economic growth. To isolate the direction of causation from religiosity to economic performance, the estimation relies on

Rachel McCleary; Robert Barro

2003-01-01

403

New Directions for Vocational Home Economics.  

ERIC Educational Resources Information Center

|A 2-day conference jointly sponsored by the American Home Economics Association and the American Vocational Association was attended by approximately 400 home economists who sought to determine new directions for vocational home economics. Some presentations were: (1) -The Cooperative Role of AHEA" by D. Hanson, (2) "Vocational Home Economics in…

Fane, Xenia F.

404

New Directions for Vocational Home Economics.  

ERIC Educational Resources Information Center

A 2-day conference jointly sponsored by the American Home Economics Association and the American Vocational Association was attended by approximately 400 home economists who sought to determine new directions for vocational home economics. Some presentations were: (1) -The Cooperative Role of AHEA" by D. Hanson, (2) "Vocational Home Economics in…

Fane, Xenia F.

405

Foreign debt, economic growth and economic crisis  

Microsoft Academic Search

Purpose – The purpose of this paper is to examine the relationship between foreign debt, economic growth and economic crisis. Design\\/methodology\\/approach – This paper constructs a Ramsey-Cass-Koopmans model theoretically and examines empirically the relationship between foreign debt, economic growth and economic crisis using US data over the period of 2003 and 2008. Findings – The paper finds that if the

Xuan Changyong; Sun Jun; Yan Chen

2012-01-01

406

Fetal viability as a threshold to personhood. A legal analysis.  

PubMed

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 viability in the Roe vs. Wade decision was intended to apply only to abortion (and is diminishing there), state courts have accepted viability as equating personhood and have used the concept to decide medical treatment, wrongful death, and criminal cases. In order to resolve the inconsistencies exhibited by these decisions, states should be allowed to make all decisions regarding the treatment of fetuses. PMID:8568420

Peterfy, A

1995-12-01

407

Economic History Services  

NSDL National Science Digital Library

Despite its reputation as Âthe dismal scienceÂ, economics continues to attract new scholars in great numbers every year, and a number of websites provide high-quality materials for those interested in the subject. The Economic History Services website began life in 1994 as a mere discussion list, and since then has grown to include numerous resources that include book reviews, a collection of course syllabi, a directory of economic historians, along with the ever-popular ÂHow Much is That? service. The ÂHow Much is That? area is quite useful, as visitors can use it to determine historical prices for goods and services, interest rates, wage rates, and inflation rates. Budding economic historians will want to check out the ÂAsk The Professor feature, which allows users to submit queries related to the subject. The section also contains an archive of answered questions, which include such enigmas as ÂIs deflation bad for the economy? The site also includes a calendar of events for persons interested in learning about upcoming lectures, conferences, workshops, and the like.

408

Selective, sensitive and economical method for the adsorptive voltammetric determination of trace amounts of Mo(VI) in organic matter rich environmental samples.  

PubMed

A differential pulse adsorptive stripping voltammetric method has been developed for molybdenum trace determination in environmental water samples containing organic compounds. It was proved that interferences from the organic matrix such as surface active substances and humic substances could be removed by the addition of resin to the analysed sample prior to voltammetric measurement. The parameters for Mo(VI) determination in the presence of resin, using a hanging mercury drop as the working electrode, were examined systematically for two complexing agents: cupferron and chloranilic acid. The detection limits estimated from 3 times the standard deviation for a low Mo(VI) concentrations were equal to 5 × 10(-11) and 3 × 10(-10) mol L(-1) for cupferron and chloranilic acid, respectively. At the optimized conditions the quantitative Mo(VI) determination in the presence of even 50 mg L(-1) of surface active compounds can be performed. The proposed procedures were validated in the course of Mo(VI) determination in certified reference material NASS-5 and in the course of studying recovery of Mo(VI) from spiked river water samples. PMID:21376963

Grabarczyk, Malgorzata; Koper, Anna

2011-01-26

409

Determination of the optimal installation capacity of small hydro-power plants through the use of technical, economic and reliability indices  

Microsoft Academic Search

One of the most important issues in planning Small Hydro-Power Plants (SHPPs) of the “run-off river” type is to determine the optimal installation capacity of the SHPP and estimate its optimal annual energy value. In this paper, a method to calculate the annual energy is presented, as is the program developed using Excel software. This program analyzes and estimates the

S. M. H. Hosseini; F. Forouzbakhsh; M. Rahimpoor

2005-01-01

410

Cosmological viability conditions for f(T) dark energy models  

NASA Astrophysics Data System (ADS)

Recently f(T) modified teleparallel gravity where T is the torsion scalar has been proposed as the natural gravitational alternative for dark energy. We perform a detailed dynamical analysis of these models and find conditions for the cosmological viability of f(T) dark energy models as geometrical constraints on the derivatives of these models. We show that in the phase space exists two cosmologically viable trajectory which (i) The universe would start from an unstable radiation point, then pass a saddle standard matter point which is followed by accelerated expansion de sitter point. (ii) The universe starts from a saddle radiation epoch, then falls onto the stable matter era and the system can not evolve to the dark energy dominated epoch. Finally, for a number of f(T) dark energy models were proposed in the more literature, the viability conditions are investigated.

Setare, M. R.; Mohammadipour, N.

2012-11-01

411

Functional maturation of neocortex: a base of viability.  

PubMed

The term "viability" is not simply a synonymous with being "born alive," but is closely related to the capability of having a "meaningful life" and having a reasonable period of survival. The definition of "viability" is generally based on two major criteria: the biological, which takes into consideration the maturity of the foetus, and the epidemiological, which is based on the survival rates reported in literature. The neuromaturation of the cerebral cortex is a dynamic process promoted by the subplate, a transient population of neurons that guides the development of cortical and thalamocortical connections. These connections are for example fundamental for cortical processing of sensory information and mental processes. The first thalamocortical and cortico-cortical connections grows at 23-24 postconceptional weeks, which coincides with the age limit for premature baby survival. PMID:22393933

Gatti, M G; Becucci, E; Fargnoli, F; Fagioli, Massimo; Ådén, U; Buonocore, G

2012-03-06

412

Song Diversity Predicts the Viability of Fragmented Bird Populations  

PubMed Central

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.

Laiolo, Paola; Vogeli, Matthias; Serrano, David; Tella, Jose L.

2008-01-01

413

Effects of corticosteroid on the expressions of neuropeptide and cytokine mRNA and on tenocyte viability in lateral epicondylitis  

PubMed Central

Background The purpose of this study was to determine the reaction mechanism of corticosteroid by analyzing the expression patterns of neuropeptides (substance P (SP), calcitonin gene related peptide (CGRP)) and of cytokines (interleukin (IL)-1?, tumor growth factor (TGF)-?) after corticosteroid treatment in lateral epicondylitis. In addition, we also investigated whether corticosteroid influenced tenocyte viability. Methods The corticosteroid triamcinolone acetonide (TAA) was applied to cultured tenocytes of lateral epicondylitis, and the changes in the mRNA expressions of neuropeptides and cytokines and tenocyte viabilities were analyzed at seven time points. Quantitative real-time polymerase chain reaction and an MTT assay were used. Results The expression of SP mRNA was maximally inhibited by TAA at 24 hours but recovered at 72 hours, and the expressions of CGRP mRNA and IL-1? mRNA were inhibited at 24 and 3 hours, respectively. The expression of TGF-? mRNA was not significant. Tenocyte viability was significantly reduced by TAA at 24 hours. Conclusions We postulate that the reaction mechanism predominantly responsible for symptomatic relief after a corticosteroid injection involves the inhibitions of neuropeptides and cytokines, such as, CGRP and IL-1?. However the tenocyte viability was compromised by a corticosteroid.

2012-01-01

414

Optical Wireless for Intravehicle Communications: A Channel Viability Analysis  

Microsoft Academic Search

This paper provides an initial analysis into the viability of implementing an optical wireless system for intravehicle communications. Based on the use of a simple linearly scalable infrared light-emitting-diode transmitter, the results for received power, bandwidth, and root-mean-square (RMS) delay spread are shown at more than 3000 locations within a sports utility vehicle. Several of these locations, including the rear

Matthew D. Higgins; Roger J. Green; Mark S. Leeson

2012-01-01

415

Long-term viability of preserved eukaryotic algae  

Microsoft Academic Search

Levels of viability of Chlorella emersonii after storage of dried material for one year were 0.1% on rehydration, all other\\u000a dried organisms examined in this study failed to recover after prolonged storage. In addition, no detectable recovery was\\u000a observed in any of the algae tested after storage of freeze-dried cultures. Methods have also been developed to cryopreserve\\u000a a range of

John G. Day; Makoto M. Watanabe; G. John Morris; Roland A. Fleck; Mark R. McLellan

1997-01-01

416

Phenomenological viability of orbifold models with three Higgs families  

Microsoft Academic Search

We discuss the phenomenological viability of string multi-Higgs doublet models, namely a scenario of heterotic Z3 orbifolds with two Wilson lines, which naturally predicts three supersymmetric families of matter and Higgs fields. We study the orbifold parameter space, and discuss the compatibility of the predicted Yukawa couplings with current experimental data. We address the implications of tree-level flavour changing neutral

Nicolás Escudero; Carlos Muñoz; Ana M. Teixeira

2006-01-01

417

Embryonic platelet-activating factor: an indicator of embryo viability  

Microsoft Academic Search

BACKGROUND: A definitive need exists to identify a biomarker of embryonic viability. Platelet-activating factor (PAF) production by human embryos is related to pregnancy potential. METHODS: Conditioned embryo culture media were obtained following conventional IVF on day 3, with PAF levels and pregnancy outcomes correlated. RESULTS: Overall pregnancy rate was 68% (17\\/25) with a mean of 84.1 ( 8.5) pmol\\/l\\/embryo PAF

W. E. Roudebush; J. D. Wininger; A. E. Jones; G. Wright; A. A. Toledo; H. I. Kort; J. B. Massey; D. B. Shapiro

2002-01-01

418

Research paper: Characteristics associated with Regional Health Information Organization viability  

Microsoft Academic Search

ObjectiveRegional Health Information Organizations (RHIOs) will likely play a key role in our nation's effort to catalyze health information exchange. Yet we know little about why some efforts succeed while others fail. We sought to identify factors associated with RHIO viability.DesignUsing data from a national survey of RHIOs that we conducted in mid-2008, we examined factors associated with becoming operational

Julia Adler-Milstein; John Landefeld; Ashish K. Jha

2010-01-01

419

Cell viability analysis using trypan blue: manual and automated methods.  

PubMed

One of the traditional methods of cell viability analysis is the use of trypan blue dye exclusion staining. This technique has been the standard methodology used in academic research laboratories and industrial biotechnology plants. Cells were routinely counted manually with a hemocytometer. In recent years, modern automated instrumentation has been introduced to supplement this traditional technique with the efficiency and reproducibility of computer control, advanced imaging, and automated sample handling. PMID:21468962

Louis, Kristine S; Siegel, Andre C

2011-01-01

420

Economic Information: First Union  

NSDL National Science Digital Library

First Union, a large bank holding company, has made available its economic publications at its web site. The Economic Indicator Analysis section analyzes the main economic indicators as they are released, such as GDP, durable goods orders, housing demand, trade deficit, and prices. The Weekly Economic Commentary examines a domestic economic issue, while the Weekly International Economic Commentary offers a brief survey of selected aspects of the global economic situation. The site also houses the Regional Economic Review, Quarterly Economic Outlook, and summary tables of economic and financial data.

421

Disruptive viability selection on adult exploratory behaviour in eastern chipmunks.  

PubMed

Heterogeneous forces of selection associated with fluctuating environments are recognized as important factors involved in the maintenance of inter-individual phenotypic variance within populations. Consistent behavioural differences over time and across situations (e.g. personality) are increasingly cited as examples of individual variation observed within populations. However, the suggestion that heterogeneous selective pressures target different animal personalities remains largely untested in the wild. In this 5-year study, we investigated the dynamics of viability selection on a personality trait, exploration, in a population of eastern chipmunks (Tamias striatus) experiencing substantial seasonal variations in weather conditions and food availability associated with masting trees. Contrary to our expectations, we found no evidence of fluctuating selection on exploration. Instead, we found strong disruptive viability selection on adult exploration behaviour, independent of seasonal variations. Individuals with either low or high exploration scores were almost twice as likely to survive over a 6-month period compared with individuals with intermediate scores. We found no evidence of viability selection on juvenile exploration. Our results highlight that disruptive selection might play an important role in the maintenance of phenotypic variance of wild populations through its effect on different personality types across temporally varying environmental conditions. PMID:23437956

Bergeron, P; Montiglio, P-O; Réale, D; Humphries, M M; Gimenez, O; Garant, D

2013-02-25

422

Viability studies of optically trapped T-cells  

NASA Astrophysics Data System (ADS)

We present a viability study of optically trapped live T cell hybridomas. T cells form an important part of the adaptive immune response system which is responsible for fighting particular pathogens or diseases. The cells of interest were directly trapped by a laser operating at a wavelength of 1064 nm and their viability measured as a function of time. Cell death was monitored using an inverted fluorescent microscope to observe the uptake by the cell of the fluorescent dye propidium iodide. Studies were undertaken at various laser powers and beam profiles. There is a growing interest in optically trapping immune cells and this is the first study that investigates the viability of a T cell when trapped using a conventional optical trapping system. In such experiments it is crucial that the T cell remains viable and trapping the cell directly means that any artefacts due to a cell-bead interface are removed. Our motivation behind this experiment is to use optical tweezers to gain a greater understanding of the interaction forces between T cells and antigen presenting cells. Measuring these interactions has become important due to recent theories which indicate that the strength of this interaction may underlie the activation of the T-cell and subsequent immune response.

McAlinden, Niall; Glass, David G.; Millington, Owain; Wright, Amanda J.

2011-09-01

423

Honeybee workers use cues other than egg viability for policing.  

PubMed

Worker policing, wherein social insect workers prevent their sisters from reproducing by eating worker-laid eggs, is recognized as a textbook example of kin selection in action. However, the evolutionary basis of policing was recently challenged in a study that suggested that police-workers remove worker-laid eggs not because rearing workers' sons reduces worker fitness, but merely because worker-laid eggs have low viability. Here, we refute Pirk et al.'s conclusions. First, we confirm earlier work that showed equal viability of eggs laid by queens and workers. Second, a statistical analysis of the data of Pirk et al. reveals that their own data do not support the conclusion that worker-laid eggs are policed merely because of their low viability. Third, we present data that unequivocally show that police-workers cannot discriminate between dead and live eggs. Hence, our study seriously weakens the challenge to the kin-selected basis of policing in honeybees. PMID:17148146

Beekman, Madeleine; Oldroyd, Benjamin P

2005-06-22

424

Nuclear cardiac imaging for the assessment of myocardial viability  

PubMed Central

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

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

425

Comparative study of classical, colorimetric and immunologic staining methods for the assessment of tumor cell viability.  

PubMed

The trypan blue exclusion test, the MTT test and an immunostaining test for apoptosis were performed before and after incubation of SW620 human colonic carcinoma cells with different cytotoxic agents (CTAs) in order to assess tumor cell viability and CTA efficacy in vitro. A modified MTT test using light microscopy was also performed. A good correlation was found between the trypan blue assay and the MTT test, as determined by spectrophotometry. There was no 'overestimation' of cell viability as measured by the trypan blue test. The monitoring of formazan formation by light microscopy was feasible, but not very reliable since it did not show a good correlation with findings determined by spectrophotometry. The apoptosis test failed to show good correlation with other tests. Distilled water had no relevant cytotoxic effect, while chlorhexidine cetrimide (HAC 3.5%), chloramine 0.5% and polyvinylpyrrolidone iodine (PVP-I) > or = 0.05% damaged a large majority of cells. PVP-I at a concentration of > or = 5% was found to be the most effective CTA. PMID:8938951

Basha, G; Yap, P; Penninckx, F

1996-01-01

426

Effect of the kinetics of temperature variation on Saccharomyces cereuisiae viability and permeability  

Microsoft Academic Search

The variation rate of the temperature increase was found to have a great effect on the viability of Saccharomyces cerevisiae subjected to heat perturbations between 25°C and 50°C. A low intensity of the increase rate of temperature could maintain an important viability of the cells (about 34% of the initial population) with regard to the corresponding viability (about 1%) observed

Patrick Gervais; Iñigo Martinez de Marañon

1995-01-01

427

Contested paradigms of ‘viability’ in redistributive land reform: perspectives from southern Africa  

Microsoft Academic Search

Viability’ is a key term in debates about land redistribution in southern African and beyond. It is often used to connote ‘successful’ and ‘sustainable’– but what is meant by viability in relation to land reform, and how have particular conceptions of viability informed state policies and planning approaches over time? How have such notions influenced the contested politics of land

Ben Cousins; Ian Scoones

2010-01-01

428

Comparative evaluation of effects of chlorhexidine and tetracycline on neutrophil viability and functions in vitro  

PubMed Central

Background: Chlorhexidine (CHX) and Tetracycline (TET) are the two antimicrobial agents used in the management of periodontal infections, due to their antimicrobial potency and substantivity. The benefits and limitations of an antimicrobial agent can only be assessed by determining their relative toxicity to microbes and host cells. Objectives: (1) To detect the effects of CHX and TET on neutrophil viability and functions in vitro. (2) To compare the effects of CHX and TET on crevicular blood neutrophils. Materials and Methods: Crevicular blood was collected using 5-?l pipette, stored in EDTA-containing vacutainers and sent for evaluation of Cell Viability- Neutrophils would be mixed with 0.25 volume of 0.4% trypan blue in Hank's balanced salt solution (HBSS) and counted to assess the viability. Chemotaxis- Evaluated under agarose slides, a total of 100 ?l crevicular blood Neutrophils-0.2% BSA or HBSS-0.2% containing concentration of CHX and TET. Oxidative Metabolism- would be assessed using nitro blue tetrazolium. In all experiments, three concentrations of TET (0.1%, 0.05%, 0.025%) and CHX (0.01%, 0.005%, 0.0025%) respectively were used. N-Formyl methionyl leucyl phenylalanine (1 ?m) in the presence of 2 ?g/ml cytochalasin B will be used as the activating agent. Neutrophils would be treated with CHX and TET similarly to that for chemotaxis. Results: TET comparatively has less deleterious effects on neutrophil functions as compared with that of CHX with statistically significant results for all parameters tested. Conclusion: From this study, it is inferred that CHX and TET do cause certain changes in neutrophil functions.

Dundappa, Jyothi; Kanteshwari, K.

2012-01-01

429

Introduce a dexamethasone mouse model for monitoring in vivo viability of stored human platelets.  

PubMed

OBJECTIVES: The aim of this study is to establish an available animal model which can evaluate in vivo viability of stored human platelets (HuPLTs). BACKGROUND: The viability in vivo of HuPLTs was usually evaluated by transfusing HuPLTs into animals before clinical trials. It is necessary to develop a method which may slow down rapid clearance of HuPLTs from circulation of the animal. METHODS: Carbon clearance tests were performed by treating mice with dexamethasone (DEX) to determine the phagocytic ability of the mice macrophages. HuPLTs in mice whole blood were detected by flow cytometric analysis with mouse anti-human CD41-fluorescein isothiocyanate monoclonal antibody. Recovery and survival of the HuPLTs stored at 22 °C for 1?day were evaluated after transfusing these HuPLTs into DEX-treated mice, and compared with those either stored at 22 °C for 5?days or at 4 °C for 1?day. RESULTS: Corrected phagocytic indexes of DEX-treated mice decreased significantly compared with those of control mice (P?viability of stored HuPLTs. PMID:23772863

Xie, R F; Yang, J; Ren, Y N; Fan, H H; Qian, K C

2013-06-18

430

Effects of High Pressure on the Viability, Morphology, Lysis, and Cell Wall Hydrolase Activity of Lactococcus lactis subsp. cremoris  

Microsoft Academic Search

Viability, morphology, lysis, and cell wall hydrolase activity of Lactococcus lactis subsp. cremoris MG1363 and SK11 were determined after exposure to pressure. Both strains were completely inactivated at pressures of 400 to 800 MPa but unaffected at 100 and 200 MPa. At 300 MPa, the MG1363 and SK11 populations decreased by 7.3 and 2.5 log cycles, respectively. Transmission electron microscopy

A. S. Malone; T. H. Shellhammer; P. D. Courtney

2002-01-01

431

Blastocyst viability and generation of transgenic cattle following freezing of in vitro produced, DNA-injected embryos  

Microsoft Academic Search

This study examined whether the viability, determined in vitro, of DNA-injected bovine embryos produced in vitro was affected by freezing, and if the frozen embryos developed to term following transfer to recipients. In vitro fertilized zygotes were injected with the pBL1 gene and then co-cultured with mouse embryonic fibroblasts (MEF) in CR1aa medium. Embryos were prepared for cryopreservation by exposure

Y. M Han; S. J Kim; J. S Park; I. Y Park; Y. K Kang; C. S Lee; D. B Koo; T. H Lee; D. Y Yu; Y. H Kim; K. J Lee; K. K Lee

2000-01-01

432

Viability of Carbon Dioxide Storage in Deep Sea Sediment  

NASA Astrophysics Data System (ADS)

Despite the public's general aversion to using the ocean to dispose of captured carbon dioxide (CO2), recent revisions of the London Protocol have removed a hurdle to subsea injection of CO2. This paper constructs a map of the worldwide "prospectivity" of CO2 storage in deep sea sediment, i.e. amenable locations are determined and storage capacities estimated. CO2 injected into deep sea sediment is expected to be gravitationally trapped and secondarily capped by CO2 hydrate formation. Capture, transport, and storage costs are estimated and a mixed-integer linear programming model that generates spatially optimized infrastructure networks is applied. The model captures CO2 from fixed point sources, uses minimum cost routing paths, aggregates CO2 flow into trunk distribution pipelines where appropriate, and injects the CO2 in potential deep sea injection sites. Economies of scale for this climate change mitigation intervention in the United States Exclusive Economic Zone are discussed, including provisions for destabilizing and/or harvesting methane from in situ gas hydrates.

Bielicki, J. M.

2007-12-01

433

Economic growth, ecological economics, and wilderness preservation  

Treesearch

Jul 21, 2013 ... Global Forest Information Service ... Perpetual economic growth and wilderness preservation are mutually ... The alternative, ecological economics paradigm faces a formidable struggle for credibility in the policy arena.

434

Economics is philosophy, economics is not science  

Microsoft Academic Search

An environmentalist's outlook is typically claimed to be based on or even constituted by sound science. It would be natural then for a version of economics based on such insights to claim to be 'even more' scientific than traditional economics. I argue for a conclusion radically opposed to this. I suggest that a genuinely green economics will\\/should eschew any claims

Rupert Read

2007-01-01

435

China Report, Economic Affairs.  

National Technical Information Service (NTIS)

This report contains articles on Economic Affairs from China. The Topics include National affairs and Policy, Provincial Affairs, Economic Statistics, Foreign Trade and Investment, Economic Zones, Finance and Banking, Industry, Agriculture, Construction a...

1987-01-01

436

Emergy evaluation and economic analysis of three wetland fish farming systems in Nansi Lake area, China.  

PubMed

Emergy and economic methods were used to evaluate and compare three fish production models, i.e., cage fish farming system, pond intensive fish rearing system and semi-natural extensive pond fish rearing system, in Nansi Lake area in China in the year 2007. The goal of this study was to understand the benefits and driving forces of selected fish production models from ecological and economic points of view. The study considered input structure, production efficiency, environmental impacts, economic viability and sustainability. Results show that the main difference among the three production systems was the emergy cost for fish feed associated with their feeding system, i.e., feeding on natural biomass such as plankton and grass or on commercial feedstock. As indicated by EYR, ELR and ESI, it can be clearly shown that the intensive production model with commercial feed is not a sustainable pattern. However, the point is that more environmentally sound patterns do not seem able to provide a competitive net profit in the short run. The intensive pond fish farming system had a net profit of 2.57E+03 $/ha, much higher than 1.27E+03 $/ha for cage fish farming system and slightly higher than 2.37E+03 $/ha for semi-natural fish farming system. With regard to the drivers of local farmer's decisions, the accessibility of land for the required use and investment ability determine the farmer's choice of the production model and the scale of operation, while other factors seem to have little effect. Theoretically, the development of environmentally sustainable production patterns, namely water and land conservation measures, greener feed as well as low waste systems is urgently needed, to keep production activities within the carrying capacity of ecosystems. Coupled emergy and economic analyses can provide better insight into the environmental and economic benefits of fish production systems and help solve the problems encountered during policy making. PMID:20970243

Zhang, L X; Ulgiati, S; Yang, Z F; Chen, B

2010-10-20

437

Cell Viability Assessment: Toward Content-Rich Platforms  

PubMed Central

Importance of the field Monitoring cell viability in vitro is critical in many areas of biomedical research, and the ultimate goal in drug discovery is the ability to predict the in vivo toxicology of drug candidates based on their toxicity profile in vitro. Over the last decade, the contribution of high-throughput screening (HTS) toward this goal has been tremendous, providing the ability to screen compounds in parallel against multiple cell types. However, the toxic effects of drug candidates uncovered during clinical trials are by far the main reason for their failure. Over the same period, our understanding of programmed cell death has evolved dramatically with the identification of critical control points in the cell death pathways. As a result, cell viability should no longer be characterized solely on the basis of discrete endpoint measurements such as membrane permeability. Areas covered in this review/What the reader will gain This review summarizes the traditional viability assays currently commercially available, focusing on methods amenable to high density format. Assays categorized into the following classes are discussed: dye exclusion assays, DNA condensation-based assays and assays monitoring a metabolic function. We describe each approach, and using case studies, we emphasize their limitations. Take home message Current low-content methods based on single parameter readouts are prone to error due to the heterogeneity of cell populations and the multi-faceted nature of cell death. High-content approaches based on continuous, multiplexed readouts are becoming increasingly important for monitoring multiple markers of cell death induction simultaneously, on a cell by cell basis. The use of such content-rich platforms is a necessity to predict the toxicology of drug candidates accurately.

Ramirez, Christina Nicole; Antczak, Christophe; Djaballah, Hakim

2013-01-01

438

Interleukin-1 receptor role in the viability of corneal myofibroblasts  

PubMed Central

The purpose of this study was to investigate the role of interleukin-1 (IL-1) in modulating myofibroblast viability in mouse corneas with stromal opacity. Twenty-four female B6;129S1-Il1r1tm1Roml/J homozygous IL-1RI knockout mice and 24 control B6129SF2/J mice were included in this study. Each mouse had opacity-generating irregular phototherapeutic keratectomy (PTK) performed with an excimer laser in one eye. Groups of 8 mice from each group were euthanized at one month, three months and six months after surgery and the eyes cryo-preserved. The contralateral eye served as unwounded control. Immunohistochemistry was performed for ?-smooth muscle actin (SMA) in central sections of all corneas. The TUNEL assay for apoptosis was performed on 8 sections of four eyes from each group. No SMA+ cells were detected in the stroma of unwounded control or knockout corneas. SMA+ myofibroblast density was significantly higher (p < 0.001) in the IL-1RI knockout group than in the control group at one month, three and six months after irregular PTK. Mean TUNEL+ stromal cells in the anterior 50 µm of stroma was significantly lower in the IL-1RI knockout group compared to the control group at six months after irregular PTK (p = 0.04). These results corroborate the findings of recent in vitro work that demonstrated an antagonistic effect of TGF? and IL-1 on myofibroblast viability, and found that IL-1-triggered myofibroblast apoptosis was suppressed by TGF?. Thus, IL-1 is an important modulator of myofibroblast viability during corneal wound healing.

Barbosa, F. L.; Lin, M.; Santhiago, M. R.; Singh, V.; Agrawal, V.; Wilson, S. E.

2012-01-01

439

Monitoring water supplies for weaponized bacteria and bacterial toxins using rapid fluorescence-based viability and affinity assays  

NASA Astrophysics Data System (ADS)

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 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.

Van Tassell, Roger L.; Evans, Mishell

440

Applications of a rapid endospore viability assay for monitoring UV inactivation and characterizing arctic ice cores.  

PubMed

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. PMID:17021233

Shafaat, Hannah S; Ponce, Adrian

2006-10-01

441

Effect of vital dyes on retinal pigmented epithelial cell viability and apoptosis: implications for chromovitrectomy.  

PubMed

Purpose: To investigate the in vitro effect of vital dyes on toxicity and apoptosis in a human retinal pigment epithelial cell line. Methods: ARPE-19 cells were exposed to brilliant blue (BBG), Evans Blue (EB), bromophenol blue (BroB), indocyanine green (ICG), infracyanine green (IfCG), light green (LG), fast green (FG), indigo carmine (IC) and Congo red (CR). Balanced salt solution was used as the control. Five different concentrations and 2 exposure times were tested. Cell viability was determined by the MTS (1-solution methyl thiazolyl tetrazolium) assay and apoptosis by Bax expression on Western blot. Results: All dyes significantly reduced cell viability after 3 min of exposure at all concentrations (p < 0.01), except for BBG that was safe at concentrations up to 0.25 mg/ml and CR up to 0.05 mg/ml, while LG was safe at all concentrations. Toxicity was higher after 30 min of exposure. Expression of Bax was upregulated after all dye exposures, except BBG; ICG had the highest Bax expression (p < 0.01). Conclusions: Overall the safest dye was BBG followed by LG, IfCG, FG, CR, IC, BroB, EB and ICG. ICG was toxic at all concentrations and exposure times tested. Moreover, BBG was the only dye that did not induce apoptosis in ARPE-19 cells. © 2013 S. Karger AG, Basel. PMID:24022718

Penha, Fernando M; Pons, Marianne; de Paula Fiod Costa, Elaine; Rodrigues, Eduardo B; Maia, Mauricio; Marin-Castaño, Maria E; Farah, Michel Eid

2013-09-06

442

Effect of cadmium on cellular viability in two species of microalgae (Scenedesmus sp. and Dunaliella viridis).  

PubMed

We determined the effect of several concentrations of cadmium (0, 5, 10, and 20 microg/l) on cellular viability in the microalgae Scenedesmus sp. and Dunaliella viridis, by measuring growth at 0, 24, 48, 72, and 96 h and pigment production at 10 days. Algae were obtained from the Nonvascular Plant Laboratory collection, in the Facultad Experimental de Ciencias, Universidad del Zulia, Venezuela. Growth was measured by cellular counting, while pigment content was evaluated using conventional spectrophotometric techniques. Growth of both species decreased in the exposed cultures comparing with the control, but its behavior was similar, because in both control and exposed cultures, its was observed an adaptive phase in the first hours, as well as a growth phase after 72 h. Cadmium concentrations above 10 microg/l produced an adverse effect on pigment production, depending on the concentration and/or exhibition time. However, even though cadmium inhibited growth and pigment production, levels of both parameters indicated cellular viability, demonstrating the adaptability of the algae cultures when they were exposed to the metal. PMID:19172231

Marcano, Letty Beatriz C; Carruyo, Ingrid M; Montiel, Xiomara M; Morales, Carolina B; de Soto, Patricia Moreno

2009-01-27

443

Application of cyclic biamperometry to viability and cytotoxicity assessment in human corneal epithelial cells.  

PubMed

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. PMID:23443523

Rahimi, Mehdi; Youn, Hyun-Yi; McCanna, David J; Sivak, Jacob G; Mikkelsen, Susan R

2013-02-27

444

Effects of lead on viability and intracellular metal content of C6 rat glioma cells  

SciTech Connect

Cultured C6 rat glioma cells were exposed to lead (Pb) acetate (0, 1, 10, or 100 ..mu..M) for 3-4 d. Cells were analyzed for changes in viability and intracellular lead, iron, and copper concentrations after Pb treatment was discontinued. The results were compared with previous findings on astroglia and oligodendroglia in culture in order to evaluate C6 cultures as a model for Pb toxicity in glia. Viability was measured by three methods on the day Pb was removed from the cells (designated d 0), and 2 and 9 d after Pb treatment was discontinued (designated d 2 and 9). The methods used were trypan blue dye exclusion, total cell counts, and incorporation of (/sup 3/H)-L-leucine into proteins. With respect to Pb and Fe uptake, C6 cells closely resembled immature astroglia in culture. Unlike C6 cells, however, astroglia showed elevations of intracellular Fe and Cu after treatment. Thus, Pb effects on C6 cells resembled those on cultured oligodendroglia and astroglia in some respects but not in others. C6 cells appear to be an adequate model for selected events in glial toxicosis, such as PB-stimulated protein synthesis in oligodendroglia and Pb uptake in astroglia, but not Pb-induced alterations of intracellular Cu and Fe in astroglia. Their use as a model for glial progenitor cells in Pb toxicity studies remains to be determined.

Tiffany-Castiglioni, E.; Garcia, D.M.; Wu, J.N.; Zmudzki, J.; Bratton, G.R.

1988-01-01

445

Study of the competitive viability of minority fuel oil marketers. Final report  

SciTech Connect

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.

None

1981-09-30

446

Ozone affects pollen viability and NAD(P)H oxidase release from Ambrosia artemisiifolia pollen  

PubMed Central

Air pollution is frequently proposed as a cause of the increased incidence of allergy in industrialised countries. We investigated the impact of ozone (O3) on reactive oxygen species (ROS) and allergen content of ragweed pollen (Ambrosia artemisiifolia). Pollen was exposed to acute O3 fumigation, with analysis of pollen viability, ROS and nitric oxide (NO) content, activity of nicotinamide adenine dinucleotide phosphate (NAD[P]H) oxidase, and expression of major allergens. There was decreased pollen viability after O3 fumigation, which indicates damage to the pollen membrane system, although the ROS and NO contents were not changed or were only slightly induced, respectively. Ozone exposure induced a significant enhancement of the ROS-generating enzyme NAD(P)H oxidase. The expression of the allergen Amb a 1 was not affected by O3, determined from the mRNA levels of the major allergens. We conclude that O3 can increase ragweed pollen allergenicity through stimulation of ROS-generating NAD(P)H oxidase.

Pasqualini, Stefania; Tedeschini, Emma; Frenguelli, Giuseppe; Wopfner, Nicole; Ferreira, Fatima; D'Amato, Gennaro; Ederli, Luisa

2011-01-01

447

Effect of various concentrations of antibiotics on osteogenic cell viability and activity.  

PubMed

Infection is a common complication of open fractures. Systemic antibiotics often cause adverse events before eradication of infected bone occurs. The local delivery of antibiotics and the use of implants that deliver both growth factors and antimicrobials are ways to circumvent systemic toxicity while decreasing infection and to reach extremely high levels required to treat bacterial biofilms. When choosing an antibiotic for a local delivery system, one should consider the effect that the antibiotic has on cell viability and osteogenic activity. To address this concern, osteoblasts were treated with 21 different antibiotics over 8 concentrations from 0 to 5000?µg/ml. Osteoblast deoxyribonucleic acid content and alkaline phosphatase activity (ALP) were measured to determine cell number and osteogenic activity, respectively. Antibiotics that caused the greatest decrement include rifampin, minocycline, doxycycline, nafcillin, penicillin, ciprofloxacin, colistin methanesulfonate, and gentamicin; their cell number and ALP were significantly less than control at drug concentrations ? 200?µg/ml. Conversely, amikacin, tobramycin, and vancomycin were the least cytotoxic and did not appreciably affect cell number and ALP until very high concentrations were used. This comprehensive evaluation of numerous antibiotics' effects on osteoblast viability and activity will enable clinicians and researchers to choose the optimal antibiotic for treatment of infection and maintenance of healthy host bone. PMID:21567453

Rathbone, Christopher R; Cross, Jessica D; Brown, Kate V; Murray, Clinton K; Wenke, Joseph C

2011-02-24

448

Impact of Hypothermia upon Chondrocyte Viability and Cartilage Matrix Permeability after 1 Month of Refrigerated Storage  

PubMed Central

Background The purpose of this research was to assess the extracellular matrix and chondrocytes of articular cartilage during refrigerated storage and to determine whether changes could be detected in the time frame that cartilage is stored for clinical use. Mathods Porcine cartilage was stored as either bisected femoral heads with bone attached or plugs without the underlying bone in culture medium with fetal bovine serum for 1 month at 4 °C. Metabolic activity was tested using a resazurin reduction method on intact tissue and viable cell recovery after enzymatic tissue digestion at each time point. Cartilage plug permeability was evaluated by measuring electrical conductivity. Results Storage in culture medium provided good cartilage viability and metabolic function for 7 days; however, significant changes were observed in femoral heads (p < 0.05). All mean chondrocyte assessment values were <30% of fresh controls at 28 days. Cartilage plugs tended to perform better after 7 days of storage than the femoral heads and retained significantly higher metabolic activity (mean = 94.5% vs. 70.5%; p < 0.05). Cartilage plugs demonstrated consistent changes in electrical conductivity after 28 days of storage (p < 0.05). Conclusion Refrigerated storage of cartilage results in both loss of chondrocyte viability and matrix permeability.

Brockbank, Kelvin G.M.; Rahn, Eliza; Wright, Gregory J.; Chen, Zhenzhen; Yao, Hai

2011-01-01

449

Viability of probiotic (Bifidobacterium, Lactobacillus acidophilus and Lactobacillus casei) and nonprobiotic microflora in Argentinian Fresco cheese.  

PubMed

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. PMID:11003217

Vinderola, C G; Prosello, W; Ghiberto, T D; Reinheimer, J A

2000-09-01

450

Turkmenistan: An Economic Profile.  

National Technical Information Service (NTIS)

Contents: Geography and Climate; History and Government; Population and Labor Force; Structure and Performance of the Economy; Economic Reform; Foreign Economic Relations; Living Standards and Social Indicators; Appendix.

1993-01-01

451

Potential of chlorophyll fluorescence imaging for assessing bio-viability changes of biodeteriogen growths on stone monuments  

NASA Astrophysics Data System (ADS)

A systematic study on the use of Chlorophyll Fluorescence (CF) imaging in Pulsed Amplitude Modulated (PAM) for assessing viability changes of biodeteriogen on stone artifacts has been carried out. The experimentation has been performed on different phototrophic organisms of gravestone slabs from the monumental British Cemetery of Florence (Italy). Since the viability of these organisms and then their chlorophyll fluorescence emission is strongly dependent on the environmental conditions, a preliminary study on the effects of local patterns during the season was carried out. The trend of the fluorescence quantum yield (QYmax) at different dark adapted times in different periods of the year was determined. The results achieved in our work proves the effectiveness of the CF-PAM imaging for in situ lichen characterizations in conservation studies and defines an optimized application protocol.

Osticioli, I.; Mascalchi, M.; Pinna, D.; Siano, S.

2013-05-01

452

Effects of anticancer agents on cell viability, proliferative activity and cytokine production of peripheral blood mononuclear cells  

PubMed Central

We investigated the effects of anticancer agents on peripheral blood mononuclear cells for the purpose of providing data to support new translational chemoimmunotherapy regimens. Peripheral-blood mononuclear cells were treated with one of four anticancer agents (5-fluorouracil, irinotecan, cisplatin, and gemcitabine) for 2 h, after which cell viability was determined. For assessment of effects of each drug on proliferation and cytokine production, cells were stimulated with phytohemagglutinin for 48 h. As a result, the anticancer agents did not affect cell viability. Cell proliferation was unaffected by 5-fluorouracil and irinotecan but inhibited by cisplatin and gemcitabine. Treatment with gemcitabine enhanced the production of IFN-? and decreased the number of regulatory T cells. gemcitabine treatment increased IFN-? production among CD4 T cells but not among CD8 T cells. The results indicated that GEM had immunoregulatory properties that might support immune response against cancer. This finding has implications for designing chemoimmunotherapy strategies.

Sakai, Hiromi; Kokura, Satoshi; Ishikawa, Takeshi; Tsuchiya, Reiko; Okajima, Manabu; Matsuyama, Tatsuzou; Adachi, Satoko; Katada, Kazuhiro; Kamada, Kazuhiro; Uchiyama, Kazuhiko; Handa, Osamu; Takagi, Tomohisa; Yagi, Nobuaki; Naito, Yuji; Yoshikawa, Toshikazu

2013-01-01

453