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1

WEM — Estimation methodology to determinate the economic and financial viability of Web projects  

Microsoft Academic Search

The effort estimation in early stages of the life cycle of software projects is an essential tool for making business decisions at the need for a methodology together with an estimation model is the key to start or abort development projects software. This paper presents a new methodology to determine the economic viability of a software development project, which is

Carlos Mauricio Gaona

2011-01-01

2

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

NASA Technical Reports Server (NTRS)

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

Mavris, Dimitri N.

1998-01-01

3

Economic viability of biogas technology  

Microsoft Academic Search

Biogas has emerged as a suitable technology for providing alternative and additional sources of energy, especially for rural areas of developing countries. Although the experience gained in China and India established its technological success, social scientists are still involved in the controversial issue of its economic viability. The available literature presents very contradictory situations, ranging between the two extreme poles

S. C. Agrawal; O. P. Khare

1983-01-01

4

Economic viability of biogas technology  

SciTech Connect

Biogas has emerged as a suitable technology for providing alternative and additional sources of energy, especially for rural areas of developing countries. Although the experience gained in China and India established its technological success, social scientists are still involved in the controversial issue of its economic viability. The available literature presents very contradictory situations, ranging between the two extreme poles of high economic viability and nonviability. Such contradictory conclusions are derived since economic benefits from the technology are influenced by a number of factors. A review of the literature reveals that various factors are either not considered, or that the economics have been worked out assuming a very ideal situation, while biogas plants are operating under very different conditions. Using the coal replacement method even as coal is seldom used by villages is only a single example of this approach. In most of the developing countries, rural populations depend mainly on non-commercial fuels like firewood, dungcakes, agricultural wastes and leaves for cooking and heating purposes. Under the present technological limitations, biogas can most commonly be used for cooking and lighting. For testing the economic viability of biogas systems, a number of authors have considered the benefits in terms of savings in traditional fuels. But considering the actual thermal efficiency of different non-commercial fuel items, as well as biogas, it has still be be decided at what point of the market prices of fuel items that the biogas system becomes economically viable and remains viable. The present paper thus reviews different approaches adopted and suggested for working out the economics or the cost-benefit ratio of the biogas technology at the first stage, and then spells out the factors influencing the economic benefits of the technology under various situations, with the help of empirical

Agrawal, S.C.; Agrawal, S.; Khare, O.P.

1983-12-01

5

Economic viability of anaerobic digestion  

SciTech Connect

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

Wellinger, A. [INFOENERGIE, Ettenhausen (Switzerland)

1996-01-01

6

DETERMINATION OF 'GIARDIA' CYST VIABILITY  

EPA Science Inventory

The principal objective of this research was the development of a sensitive, standardized method of determining whether or not Giardia cysts are viable. The availability of such a method is necessary to determine the effect of chemical and physical agents on the viability of thes...

7

The Economic Viability of Mars Colonization  

Microsoft Academic Search

The economic viability of colonizing Mars is examined. It is shown, that of all bodies in the solar system other than Earth, Mars is unique in that it has the resources required to support a population of sufficient size to create locally a new branch of human civilization. It is also shown that while Mars may lack any cash material

Robert Zubrin

8

Economic viability of geriatric hip fracture centers.  

PubMed

Management of geriatric hip fractures in a protocol-driven center can improve outcomes and reduce costs. Nonetheless, this approach has not spread as broadly as the effectiveness data would imply. One possible explanation is that operating such a center is not perceived as financially worthwhile. To assess the economic viability of dedicated hip fracture centers, the authors built a financial model to estimate profit as a function of costs, reimbursement, and patient volume in 3 settings: an average US hip fracture program, a highly efficient center, and an academic hospital without a specific hip fracture program. Results were tested with sensitivity analysis. A local market analysis was conducted to assess the feasibility of supporting profitable hip fracture centers. The results demonstrate that hip fracture treatment only becomes profitable when the annual caseload exceeds approximately 72, assuming costs characteristic of a typical US hip fracture program. The threshold of profitability is 49 cases per year for high-efficiency hip fracture centers and 151 for the urban academic hospital under review. The largest determinant of profit is reimbursement, followed by costs and volume. In the authors’ home market, 168 hospitals offer hip fracture care, yet 85% fall below the 72-case threshold. Hip fracture centers can be highly profitable through low costs and, especially, high revenues. However, most hospitals likely lose money by offering hip fracture care due to inadequate volume. Thus, both large and small facilities would benefit financially from the consolidation of hip fracture care at dedicated hip fracture centers. Typical US cities have adequate volume to support several such centers. PMID:24579222

Clement, R Carter; Ahn, Jaimo; Mehta, Samir; Bernstein, Joseph

2013-12-01

9

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

Code of Federal Regulations, 2010 CFR

...false What pre-application costs will MMS consider in determining...REDUCTION IN ROYALTY RATES OCS Oil, Gas, and Sulfur General...68 What pre-application costs will MMS consider in determining...will not consider ineligible costs as set forth in §...

2010-07-01

10

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

Code of Federal Regulations, 2013 CFR

...false What pre-application costs will BSEE consider in determining...REDUCTION IN ROYALTY RATES OCS Oil, Gas, and Sulfur General § 203.68 What pre-application costs will BSEE consider in determining...will not consider ineligible costs as set forth in §...

2013-07-01

11

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

Code of Federal Regulations, 2012 CFR

...false What pre-application costs will BSEE consider in determining...REDUCTION IN ROYALTY RATES OCS Oil, Gas, and Sulfur General § 203.68 What pre-application costs will BSEE consider in determining...will not consider ineligible costs as set forth in §...

2012-07-01

12

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

Code of Federal Regulations, 2011 CFR

...false What pre-application costs will MMS consider in determining...REDUCTION IN ROYALTY RATES OCS Oil, Gas, and Sulfur General...68 What pre-application costs will MMS consider in determining...will not consider ineligible costs as set forth in §...

2011-07-01

13

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

Code of Federal Regulations, 2014 CFR

...false What pre-application costs will BSEE consider in determining...REDUCTION IN ROYALTY RATES OCS Oil, Gas, and Sulfur General § 203.68 What pre-application costs will BSEE consider in determining...will not consider ineligible costs as set forth in §...

2014-07-01

14

Economic viability of a commingled/backgrounded cattle sale  

E-print Network

OF SCIENCE Approved as to style and content by: Ermest E. Davis (Chair of Committee) Ted Mc ollum (Member) Oral Cap s (Member) M. Edward Rister (Member) A Gene Nelson (Head of Department) December 2001 Ma)or Subject: Agricultural Economics... ABSTRACT Economic Viability of a Commingled/Backgrounded Cattle Sale. (December 2001) Jaret Roy Schulte, B. S. , Texas Tech University Chair of Advisory Committee: Dr. Ernest E. Davis Focusing on the increasing emphasis of value added to the beef...

Schulte, Jaret Roy

2001-01-01

15

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...

16

A Neural Network Approach to Determining Cellular Viability John Quinn+  

E-print Network

@cbis.ece.drexel.edu Abstract ­ Determination of cellular viability is a frequent goal of flow cytometry assays, and most parameters. Cells were analyzed with a FACS caliburTM flow cytometer (Becton Dickinson) and data were

17

Economic viability of multiple-lateral horizontal wells  

E-print Network

. It will focus on the application of multiple-lateral horizontal wells to reduce the risks of economic uncertainty associated with poor reservoir characterization in areally anisotropic reservoirs. Using a state-of-the-art productivity index model, the study...

Smith, Christopher Jason

1995-01-01

18

Key issues for the economic viability of magnetic fusion power  

Microsoft Academic Search

This report presents an overview of fusion electricity generating costs relative to coal, fission, and renewables. The magnetic fusion costs are benchmarked by comparison with those for ITER. The overall conclusion is that the likely economic performance of fusion, combined with its excellent safety and environmental qualities, makes it a serious contender as one of the few major contributors to

T. C. Hender; P. J. Knight; I. Cook

1996-01-01

19

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

20

A Method for Quantitative Determination of Biofilm Viability  

PubMed Central

In this study we present a scheme for quantitative determination of biofilm viability offering significant improvement over existing methods with metabolic assays. Existing metabolic assays for quantifying viable bacteria in biofilms usually utilize calibration curves derived from planktonic bacteria, which can introduce large errors due to significant differences in the metabolic and/or growth rates of biofilm bacteria in the assay media compared to their planktonic counterparts. In the presented method we derive the specific growth rate of Streptococcus mutans bacteria biofilm from a series of metabolic assays using the pH indicator phenol red, and show that this information could be used to more accurately quantify the relative number of viable bacteria in a biofilm. We found that the specific growth rate of S. mutans in biofilm mode of growth was 0.70 h?1, compared to 1.09 h?1 in planktonic growth. This method should be applicable to other bacteria types, as well as other metabolic assays, and, for example, to quantify the effect of antibacterial treatments or the performance of bactericidal implant surfaces. PMID:24955541

Welch, Ken; Cai, Yanling; Strřmme, Maria

2012-01-01

21

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

PubMed

Nutrition is affected by numerous environmental and societal causes. This paper starts with a simple framework based on three domains: nutritional quality, economic viability, and environmental sustainability, and calls for an integrated approach in research to simultaneously account for all three. It highlights limitations in the current understanding of each domain, and how they influence one another. Five research topics are identified: measuring the three domains (nutritional quality, economic viability, environmental sustainability); modeling across disciplines; furthering the analysis of food systems in relation to the three domains; connecting climate change and variability to nutritional quality; and increasing attention to inequities among population groups in relation to the three domains. For an integrated approach to be developed, there is a need to identify and disseminate available metrics, modeling techniques, and tools to researchers, practitioners, and policy makers. This is a first step so that a systems approach that takes into account potential environmental and economic trade-offs becomes the norm in analyzing nutrition and food-security patterns. Such an approach will help fill critical knowledge gaps and will guide researchers seeking to define and address specific research questions in nutrition in their wider socioeconomic and environmental contexts. PMID:25351044

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

2014-12-01

22

Economic viability of short rotation coppice for energy production for reuse of caesium-contaminated land in Belarus  

Microsoft Academic Search

Following the Chernobyl accident, changed land use such that the products of the land are radiologically acceptable and assure an economic return is a potentially sustainable remediation option. In this study, Short rotation coppice (SRC) for energy production is evaluated as an alternative land use in contaminated areas. If the radiological and technical feasibility criteria are met, the economic viability

H. Vandenhove; F. Goor; S. O'Brien; A. Grebenkov; S. Timofeyev

2002-01-01

23

Fluorescence Microscopy Methods for Determining the Viability of Bacteria in Association with Mammalian Cells  

PubMed Central

Central to the field of bacterial pathogenesis is the ability to define if and how microbes survive after exposure to eukaryotic cells. Current protocols to address these questions include colony count assays, gentamicin protection assays, and electron microscopy. Colony count and gentamicin protection assays only assess the viability of the entire bacterial population and are unable to determine individual bacterial viability. Electron microscopy can be used to determine the viability of individual bacteria and provide information regarding their localization in host cells. However, bacteria often display a range of electron densities, making assessment of viability difficult. This article outlines protocols for the use of fluorescent dyes that reveal the viability of individual bacteria inside and associated with host cells. These assays were developed originally to assess survival of Neisseria gonorrhoeae in primary human neutrophils, but should be applicable to any bacterium-host cell interaction. These protocols combine membrane-permeable fluorescent dyes (SYTO9 and 4',6-diamidino-2-phenylindole [DAPI]), which stain all bacteria, with membrane-impermeable fluorescent dyes (propidium iodide and SYTOX Green), which are only accessible to nonviable bacteria. Prior to eukaryotic cell permeabilization, an antibody or fluorescent reagent is added to identify extracellular bacteria. Thus these assays discriminate the viability of bacteria adherent to and inside eukaryotic cells. A protocol is also provided for using the viability dyes in combination with fluorescent antibodies to eukaryotic cell markers, in order to determine the subcellular localization of individual bacteria. The bacterial viability dyes discussed in this article are a sensitive complement and/or alternative to traditional microbiology techniques to evaluate the viability of individual bacteria and provide information regarding where bacteria survive in host cells. PMID:24056524

Johnson, M. Brittany; Criss, Alison K.

2013-01-01

24

A comparative study on egg hatching methods and oncosphere viability determination for Taenia solium eggs  

Microsoft Academic Search

The efficiencies of an enzyme method and the sodium hypochlorite method in hatching eggs of Taenia solium (Henan strain) were compared. The viability of the hatched oncospheres was determined by staining with trypan blue. For the former method, the hatching rate and viability percentage were 85.7% and 79.7%, respectively. The corresponding figures for the latter method were 97.9% and 86.7%,

I. C. Wang; Y. X. Ma; C. H. Kuo; P. C. Fan

1997-01-01

25

Molecular Assays for Determining Mycobacterium leprae Viability in Tissues of Experimentally Infected Mice  

PubMed Central

Background The inability of Mycobacterium leprae to grow on axenic media has necessitated specialized techniques in order to determine viability of this organism. The purpose of this study was to develop a simple and sensitive molecular assay for determining M. leprae viability directly from infected tissues. Methodology/Principle Findings Two M. leprae-specific quantitative reverse transcription PCR (qRT-PCR) assays based on the expression levels of esxA, encoding the ESAT-6 protein, and hsp18, encoding the heat shock 18 kDa protein, were developed and tested using infected footpad (FP) tissues of both immunocompetent and immunocompromised (athymic nu/nu) mice. In addition, the ability of these assays to detect the effects of anti-leprosy drug treatment on M. leprae viability was determined using rifampin and rifapentine, each at 10 mg/kg for 1, 5, or 20 daily doses, in the athymic nu/nu FP model. Molecular enumeration (RLEP PCR) and viability determinations (qRT-PCR) were performed via Taqman methodology on DNA and RNA, respectively, purified from ethanol-fixed FP tissue and compared with conventional enumeration (microscopic counting of acid fast bacilli) and viability assays (radiorespirometry, viability staining) which utilized bacilli freshly harvested from the contralateral FP. Both molecular and conventional assays demonstrated growth and high viability of M. leprae in nu/nu FPs over a 4 month infection period. In contrast, viability was markedly decreased by 8 weeks in immunocompetent mice. Rifapentine significantly reduced bacterial viability after 5 treatments, whereas rifampin required up to 20 treatments for the same efficacy. Neither drug was effective after a single treatment. In addition, host gene expression was monitored with the same RNA preparations. Conclusions hsp18 and esxA qRT-PCR are sensitive molecular indicators, reliably detecting viability of M. leprae in tissues without the need for bacterial isolation or immediate processing, making these assays applicable for in vivo drug screening and promising for clinical and field applications. PMID:24179562

Davis, Grace L.; Ray, Nashone A.; Lahiri, Ramanuj; Gillis, Thomas P.; Krahenbuhl, James L.; Williams, Diana L.; Adams, Linda B.

2013-01-01

26

Determination of Jasminum nudiflorum pollen viability and its storage method  

Microsoft Academic Search

Using the fresh pollen of Jasminum nudiflorum as test maierial, germination in vitro, I2-kI staining and TTC staining methods were used to determine the fresh pollen ability. The relationship between pollen germination and morphology was studied, effects of different storage on the pollen germination were studied too. The results show that there was a certain correlation between pollen germination and

Wenqing Jia; Huichao Liu; Xiaohua Du; Xiaobo Xu; Yang You

2011-01-01

27

ECONOMICALLY DETERMINED LIVESTOCK QUARANTINE ZONES  

Microsoft Academic Search

This paper examines economic factors present when setting quarantine zones for contagious livestock diseases like foot-and-mouth disease (FMD). A conceptual model explores the trade-offs as zone size expands. One trade-off is between the cost of economic activity inside the zone and the benefits of reduced disease spread. There are also agricultural and non-agricultural price effects to consider. Two hypothetical counties

Philip L. Paarlberg; Ann Hillberg Seitzinger; John G. Lee

2004-01-01

28

Tiller hierarchy and defoliation frequency determine bud viability in the grass Poa ligularis  

Microsoft Academic Search

Bud viability after various defoliation frequency treatments was determined in the perennial bunchgrass Poa ligularis under arid field conditions from 2002 to 2005. Bud respiratory activity was examined on various stem base hierarchies using\\u000a the tetrazolium test, as validated with the vital stain Evan’s blue. The hypothesis of this work was that the total and viable\\u000a axillary bud numbers on

C. A. Busso; C. Gittins; G. F. Becker; L. Ghermandi

29

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

EPA Science Inventory

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

30

Escherichia coli viability determination using dynamic light scattering: a comparison with standard methods.  

PubMed

To determine the concentration of bacteria in a sample is important in the food industry, medicine and biotechnology. A disadvantage of the plate-counting method is that a microorganism colony could arise from one cell or from many cells. The other standard methodology, known as optical density determination, is based on the turbidity of a suspension and registers all bacteria, dead and alive. In this article, dynamic light scattering is proposed as a fast and reliable method to determine bacterial viability and, consequently, time evolution. Escherichia coli was selected because this microorganism is well known and easy to handle. A correlation between the data from these three techniques was obtained. We were able to calculate the growth rate, usually determined by plate counting or optical density measurement, using dynamic light scattering and to predict bacterial behavior. An analytical relationship between the colony forming units and the light scattered intensity was also deduced. PMID:24853284

Loske, Achim M; Tello, Elba M; Vargas, Susana; Rodriguez, Rogelio

2014-08-01

31

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

Code of Federal Regulations, 2010 CFR

...contain the following items for an oil and gas lease. (a) Economic...which include: (1) Starting oil and gas prices; (2) Real price growth; (3) Real cost growth...values) which shows: (1) Oil and gas production;...

2010-07-01

32

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

Code of Federal Regulations, 2014 CFR

...contain the following items for an oil and gas lease. (a) Economic...which include: (1) Starting oil and gas prices; (2) Real price growth; (3) Real cost growth...values) which shows: (1) Oil and gas production;...

2014-07-01

33

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

Code of Federal Regulations, 2013 CFR

...contain the following items for an oil and gas lease. (a) Economic...which include: (1) Starting oil and gas prices; (2) Real price growth; (3) Real cost growth...values) which shows: (1) Oil and gas production;...

2013-07-01

34

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

Code of Federal Regulations, 2012 CFR

...contain the following items for an oil and gas lease. (a) Economic...which include: (1) Starting oil and gas prices; (2) Real price growth; (3) Real cost growth...values) which shows: (1) Oil and gas production;...

2012-07-01

35

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

36

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

PubMed

This study presents a techno-economic assessment of algae-derived biodiesel under economic and technical uncertainties associated with the development of algal biorefineries. A global sensitivity analysis was performed using a High Dimensional Model Representation (HDMR) method. It was found that, considering reasonable ranges over which each parameter can vary, the sensitivity of the biodiesel production cost to the key input parameters decreases in the following order: algae oil content>algae annual productivity per unit area>plant production capacity>carbon price increase rate. It was also found that the Return on Investment (ROI) is highly sensitive to the algae oil content, and to a lesser extent to the algae annual productivity, crude oil price and price increase rate, plant production capacity, and carbon price increase rate. For a large scale plant (100,000 tonnes of biodiesel per year) the production cost of biodiesel is likely to be Ł0.8-1.6 per kg. PMID:24220544

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

2014-01-01

37

Hypericin as a marker for determination of myocardial viability in a rat model of myocardial infarction.  

PubMed

The aim of this study was to investigate the necrosis-avid agent hypericin as a potential indicator for determination of myocardial infarction (MI). Male Sprague-Dawley rats (n = 30) weighing 350 ± 20 g were subjected to acute reperfused MI. Animals were divided into four groups (n = 6), in which hypericin was intravenously injected at 0, 1, 2 and 5 mg kg(-1) respectively. One day after injection, rats were euthanized with their hearts excised for qualitative and quantitative studies by means of microscopic fluorescence examination to decide the dosage of hypericin. Another group was injected with hypericin at the decided dose and evaluated by fluorescence macroscopy in colocalization with triphenyltetrazoliumchloride (TTC) and histomorphology. Infarct-to-normal contrast ratio and relative infarct size were quantified. Hypericin-induced red fluorescence was significantly brighter in necrotic than in viable myocardium as proven by a six times higher mean fluorescence density. Mean MI area was 35.66 ± 22.88% by hypericin fluorescence and 32.73 ± 21.98% by TTC staining (R(2) = 0.9803). Global MI-volume was 34.56 ± 21.07% by hypericin and 35.11 ± 20.47% by TTC staining (R(2) = 0.9933). The results confirm that hypericin specifically labeled necrosis, and enhanced the imaging contrast between the infarcted and normal myocardium, suggesting its potential applications for the assessment of myocardial viability. PMID:24460608

Jiang, Cuihua; Li, Yue; Jiang, Xiao; Yao, Nan; Gao, Meng; Zhang, Xueli; Wang, Junying; Wang, Xiaoning; Sun, Ziping; Zhang, Jian; Ni, Yicheng

2014-01-01

38

UBC Social Ecological Economic Development Studies (SEEDS) Student Report An Investigation into the Viability of a Waste Heat Powered Greenhouse  

E-print Network

into the Viability of a Waste Heat Powered Greenhouse Do Youl Bae, Calvin Ng, Joseph Pateman University of British Investigation into the Viability of a Waste Heat Powered Greenhouse Do Youl Bae Calvin Ng Joseph Pateman March conservative to construct and maintain. Furthermore, it is a viable, low risk revenue stream generated

39

Determinants of Economic Growth: A Cross-Country Empirical Study  

Microsoft Academic Search

Research on economic growth has exploded in the past decade. Hundreds of empirical studies on economic growth across countries have highlighted the correlation between growth and a variety of variables. Determinants of Economic Growth, based on Robert Barro's Lionel Robbins Memorial Lectures, delivered at the London School of Economics in February 1996, summarizes this important literature. The book contains three

Robert J. Barro

1999-01-01

40

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

41

The determination of the viability of Schistosomal eggs by a novel technique: electrorotation.  

PubMed

Human schistosomiasis is widespread in tropical and subtropical environments. In this study, a novel open cell with liquid medium perfusion system for electrorotation measurement to detect the viability of schistosomal eggs is proposed. With no solid top or bottom surface, the liquid medium perfusion system solves some of the problems of conventional electrorotation testing systems. This kind of open cell successfully detect schistosome egg viability, most prominently, there can be no adhesion or friction of eggs on the surface to encumber their rotation. This newly proposed system can be used to test more types of biological particles compared to a conventional system used in electrorotation measurement, providing more exact results. The new system can be used for rapid analysis of various biological particles in water, which will be potentially significant to public health. PMID:24189668

Liu, L; Tang, J C; Zhang, F; Wang, X; Xu, B J

2013-09-01

42

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 "soft"…

Agarwal, Sheela; Rahman, Sanzidur; Errington, Andrew

2009-01-01

43

Determinants of Income Inequality and its Effects on Economic Growth  

Microsoft Academic Search

The paper empirically investigates, in the context of African countries, the determinants of income distribution and inequality, the effect of inequality on economic growth, and the channels through which inequality affects growth. Data for 35 countries over different periods in the last four decades were employed. Factors identified as having affected income distribution include the level of economic development attained,

Matthew O. Odedokun; Jeffery I. Round

2001-01-01

44

Factors determining the economic value of groundwater  

NASA Astrophysics Data System (ADS)

Increasing groundwater extraction threatens aquifer sustainability for future generations. Making the best use of limited groundwater resources requires knowledge of its alternative extractive and non-extractive values, as well as the cost of extraction and the hydrological interlinkages between alternative uses. Groundwater value is driven by a number of factors including its supply and demand and institutional and policy factors. These factors and how they affect value of groundwater are described. Also described are the various components relevant to the economic valuation of groundwater and there is discussion on the potential difficulties in their practical estimation. It is argued that groundwater management is essential when there are large potential spatial and temporal externalities related to groundwater pumping. Maintaining non-extractive and option values is likely to require trade-offs with current extractive uses. Well-informed management will be required to allocate groundwater efficiently between different users such as agriculture, industry and the environment, while also balancing the needs of current and future generations.

Qureshi, M. Ejaz; Reeson, Andrew; Reinelt, Peter; Brozovi?, Nicholas; Whitten, Stuart

2012-08-01

45

44 Journal of Student Research in Environmental Science at Appalachian Determining the viability of the practical  

E-print Network

energy are too low to implement solar power as an effective replacement for conventional power generation techniques. Moreover, the efficiencies of the applica- tion of solar technology on large scales have not been of Boone (TOB) in North Carolina to determine to what extent the application of current solar power

Thaxton, Christopher S.

46

Environmental and economic assessment of a greenhouse waste heat exchange  

Microsoft Academic Search

As the economic costs of energy and the negative externalities associated with the combustion of fossil fuels threaten the economic viability of greenhouses in northern climates there is a renewed interest in the use of waste heat. This paper presents a technical and economic methodology to determine the viability of establishing waste heat greenhouses using the waste heat from industrial

R. Andrews; J. M. Pearce

2011-01-01

47

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

PubMed Central

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.

2013-01-01

48

Debilitation in conidia of the entomopathogenic fungi Beauveria and Metarhizium anisopliae and implications with respect to viability determinations and mycopesticide quality assessments  

Technology Transfer Automated Retrieval System (TEKTRAN)

Viabilities of entomopathogenic fungal conidia comprising biopesticide products are most commonly determined by suspension of dry conidia from storage in a water/surfactant solution immediately before inoculation onto an agar-based germination substrate; conidia are then incubated at a moderate temp...

49

Russia: Political and Institutional Determinants of Economic Reforms  

Microsoft Academic Search

The purpose of this study is to analyze the course, determinants and political economy of economic reforms in Russia conducted in the period 1985-2003. The year 1985 can be considered an important turning point in Soviet\\/Russian history, marked as it was by the election of Mikhail Gorbachev to the position of General Secretary of the Communist Party of Soviet Union

Rafal Antczak; Vladimir Mau; Aleksey Shapovalov; Irina Sinitsina; Konstantin Yanovskiy; Sergei Zhavoronkov

2004-01-01

50

The Empirical Determination of Key Skills from an Economic Perspective  

ERIC Educational Resources Information Center

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

Van Loo, Jasper B.; Toolsema, Bert

2005-01-01

51

Economic determinants of diet in older adults: systematic review  

PubMed Central

Background and aims Many economic factors are associated with diet, yet the evidence is generally cross-sectional. Older people are considered especially vulnerable to poor diets from negative changes to varied economic factors. This review extends current knowledge on known correlates to decipher actual economic determinants of diet in older adults. Methods Eight bibliometric databases were searched between May and December 2012, supplemented by hand-searches, with no restrictions on publication date or country. Longitudinal studies, or reviews, were eligible when examining diet as a function of change in an economic factor in non-institutionalised adults ?60?years. Data were extracted using a standardised evidence table and quality assessed before narrative synthesis. Results We found nine original studies for inclusion, of which eight examined change from work to retirement and one evaluated a food price intervention. Designs were generally pre-post without controls and varying in follow-up. Studies reported mixed impact on food spending and/or food intake. Retirement was shown to both reduce and have no impact on food spending and to have either positive and negative, or positive and no impact on food intake. Subgroup differences were observed, especially between men and women. Conclusions Despite ample research on economic correlates of older adults' diets, little is still known about actual economic determinants of diet in this population. Studies of retirement suggest divergent effects in some but not all older people. Robust high-quality longitudinal studies to decipher economic drivers of diet must be prioritised in research and policy as firm conclusions remain elusive. PMID:23761410

Conklin, Annalijn I; Maguire, Eva R; Monsivais, Pablo

2013-01-01

52

Cable in Boston; A Basic Viability Report.  

ERIC Educational Resources Information Center

The viability of urban cable television (CATV) as an economic phenomenon is examined via a case study of its feasibility in Boston, a microcosm of general urban environment. To clarify cable's economics, a unitary concept of viability is used in which all local characteristics, cost assumptions, and growth estimates are structured dynamically as a…

Hauben, Jan Ward; And Others

53

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

PubMed Central

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

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

1997-01-01

54

Viability of Baylisascaris procyonis Eggs.  

PubMed

Infection with Baylisascaris procyonis roundworms is rare but often fatal and typically affects children. We attempted to determine parameters of viability and methods of inactivating the eggs of these roundworms. Loss of viability resulted when eggs were heated to 62°C or desiccated for 7 months but not when frozen at -15°C for 6 months. PMID:21762591

Shafir, Shira C; Sorvillo, Frank J; Sorvillo, Teresa; Eberhard, Mark L

2011-07-01

55

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

Code of Federal Regulations, 2012 CFR

...2012-10-01 false What rules determine social and economic disadvantage? 26.67...Standards § 26.67 What rules determine social and economic disadvantage? (a) Presumption...When an individual's presumption of social and/or economic disadvantage has...

2012-10-01

56

Determination of the viability of Toxoplasma gondii in cured ham using bioassay: influence of technological processing and food safety implications.  

PubMed

Toxoplasmosis is a zoonotic disease caused by the protozoan Toxoplasma gondii and distributed worldwide. Ingestion of viable cysts from infected raw or undercooked meat is an important route of horizontal transmission of the parasite to humans. Little information is available concerning the effect of commercial curing on cysts of T. gondii. This study is the first in which the influence of processing of cured ham on the viability of T. gondii has been evaluated, using bioassay to assess the risk of infection from eating this meat product. Naturally infected pigs were selected for the study, and a mouse concentration bioassay technique was used to demonstrate viable bradyzoites of T. gondii in porcine tissues and hams. No viable parasites were found in the final product (14 months of curing) based on results of the indirect immunofluorescence assay and histological and PCR analyses. Our results indicate that the consumption of hams cured as described here poses an insignificant risk of acquiring toxoplasmosis. However, additional studies are required to evaluate the safety of ham products cured under different conditions of curing time, salt, and nitrite concentration. PMID:21219742

Bayarri, Susana; Gracia, María J; Lázaro, Regina; Pe Rez-Arquillué, Consuelo; Barberán, Montserrat; Herrera, Antonio

2010-12-01

57

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

PubMed

A dedicated microscopy imaging system including automated positioning, focusing, image acquisition, and image analysis was developed to characterize a yeast population with regard to cell morphology. This method was used to monitor a stress-model alcoholic fermentation with Saccharomyces cerevisiae. Combination of dark field and epifluorescence microscopy after propidium iodide staining for membrane integrity showed that cell death went along with important changes in cell morphology, with a cell shrinking, the onset of inhomogeneities in the cytoplasm, and a detachment of the plasma membrane from the cell wall. These modifications were significant enough to enable a trained human operator to make the difference between dead and viable cells. Accordingly, a multivariate data analysis using an artificial neural network was achieved to build a predictive model to infer viability at single-cell level automatically from microscopy images without any staining. Applying this method to in situ microscope images could help to detect abnormal situations during a fermentation course and to prevent cell death by applying adapted corrective actions. PMID:21290616

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

2011-01-01

58

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

PubMed Central

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

Ayaki, Masahiko; Iwasawa, Atsuo; Niwano, Yoshimi

2012-01-01

59

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

Code of Federal Regulations, 2010 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...

2010-07-01

60

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

61

The Effects of Economic Factors in Determining the Transition Process in Europe and Central Asia  

Microsoft Academic Search

This paper examines how economic determinants affect foreign direct investment into a sample of Western European and transition countries from 1990 to 2003. The observed differences in the flow of foreign investment into the transition countries, relative to those in Western Europe, provokes the question of whether this phenomenon was determined by the economic factors present in those countries. Using

David A. Lopez

2010-01-01

62

The social and economic context and determinants of schistosomiasis japonica  

Microsoft Academic Search

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

Huang Yi-Xin; Lenore Manderson

2005-01-01

63

Determinants of risk-taking: Behavioral and economic views  

Microsoft Academic Search

The concept of risk-taking is examined from various perspectives: economic, decision theoretic, and psychological. Multiple factors are discussed as complicating the extraction of any presumed risk-taking propensity from a person's real-world behavior.Problem structuring, beliefs, andvalues (defined here as riskless as opposed to risky utility) may of course underlie differences in risk behavior. In addition,context andprocess factors can induce variance in

Paul J. H. Schoemaker

1993-01-01

64

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

65

Pteridophyte spores viability  

Microsoft Academic Search

\\u000a Spore viability is defined as the time that spores retain their capacity to germinate. It is a factor of primary importance\\u000a in the establishment of fern species and populations in a new habitat after spore dispersal. Viability is typically maintained\\u000a for a long period in pteridophytes, but there are great variations in both interspecific and intraspecific levels.\\u000a \\u000a \\u000a Factors affecting viability

Jose María Gabriel y Galán; Carmen Prada

66

Analytical Research to Determine the effects of the Components of ONGABO on the Viability of HepG2 Cancer Cells by Using the Sovereign, Minister, Assistant and Courier Principle (?????)  

PubMed Central

Objectives: This study used the basic principle of Oriental medicine, the sovereign, minister, assistant and courier principle (?????) to investigate the effects of the component of ONGABO, which is composed of Ginseng Radix (Red Ginseng), Angelica Gigantis Radix, Schisandrae Fructus, Cuscuta Semen and Curcumae tuber on the viability of HepG2 cells. Methods: Single and mixed extracts of the component of ONGABO were prepared by lypohilizing powder of Red Ginseng (6-year root from Kanghwa), Angelica Gigantis Radix, Schisandrae Fructus, Cuscuta Semen, Curcumae Tuber (from Omniherb Co., Ltd., Korea) at the laboratory of herbal medicine in Woosuk University and were eluted after being macerated with 100% ethanol for three days. The cell viability of HepG2 was determined by using an absorptiometric analysis with PrestoBlue (Invitrogen) reagent after the plate had been incubated for 48 hours. All of the experiments were repeated three times to obtain the average value and standard deviation. The statistical analysis was done and the correlation factor was obtained by using Microsoft Office Excel 2007 and Origin 6.0 software. Results: Although Ginseng Radix (Red Ginseng) and Schisandrae Fructus did not enhance the viability of HepG2 cells, they were shown to provide protection of those cells. On the other hand, Angelica Gigantis Radix decreased the viability of HepG2 cells significantly, Cuscuta Semen and Curcumae Tuber had a small or no effect on the viability of HepG2 cells. Conclusions: In the sovereign, minister, assistant and courier principle (?????), Ginseng Radix (Red Ginseng) corresponds to the sovereign component because it provides cell protection effects, Angelica Gigantis Radix corresponds to minister medicinal because it kills cells, Schisandrae Fructus corresponds to the assistant medicinal to help red ginseng having cell protect effects. Cuscuta Semen and Curcumae Tuber correspond to the courier medicinal having no effect in cell viability in HepG2. We hope this study provides motivation for advanced research on the sovereign, minister, assistant and courier principle.

Shin, Jeong-Hun; Jun, Seung-lyul; Hwang, Sung-Yeoun; Ahn, Seong-Hun

2012-01-01

67

Determination of the effects of temperature on viability, metabolic activity and proliferation of two Perkinsus species, and its significance to understanding seasonal cycles of perkinsosis.  

PubMed

The range of water temperatures in which Perkinsus species can survive and proliferate remains ill-defined, particularly at lower temperatures. The in vitro viability, metabolic activity, and proliferation of 3 isolates each of P. marinus and P. olseni trophozoites at 28 degrees C, and at 15 and 4 degrees C, after transfer from 28 degrees C, were compared. Both species showed declines in metabolic activity and proliferation from 28 degrees C to 15 degrees C. At 4 degrees C, both species had viability after 30 days incubation time (P. marinus 49%, P. olseni 58%), but limited metabolic activity and no proliferation. Perkinsus marinus viability was further compared when transferred directly from 28 degrees C, 18 degrees C and progressively from 18 degrees C (0.5 degrees C/day) to 2, 4 and 6 degrees C and maintained for up to 4 months. Viability was highest under progressive transfer (77% and 54% after 30 and 60 days exposure to test temperatures). The decrease in P. marinus viability at the lower temperatures in vitro only partially explains decreasing parasite infection intensities in eastern oysters in the colder months of the year. Moreover, the significant decrease in parasite infection intensities in late winter and early spring, as temperatures increase, is likely due to an active process of elimination by oyster host defences. PMID:18248687

La Peyre, M K; Casas, S M; Villalba, A; La Peyre, J F

2008-04-01

68

The Determinants of Child Health in Pakistan: An Economic Analysis  

ERIC Educational Resources Information Center

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

Shehzad, Shafqat

2006-01-01

69

Economic Education in the Middle East: Are the Determinants of Success in Introductory Economics Any Different?  

ERIC Educational Resources Information Center

The author examines the determinants of success in introductory microeconomics, in the context of a Middle Eastern society but within an American educational setting. The data set is rich and covers over 3,500 students in one regional campus, allowing control for a wide range of student and class characteristics, one of which, nationality, is…

Kherfi, Samer

2008-01-01

70

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...

71

Determinants of market-assessed sovereign risk: Economic fundamentals or market risk appetite?  

Microsoft Academic Search

This paper examines the determinants of the market-assessed sovereign risk premium, measured by the Brady bond stripped yield spread. Our study shows that, while standard economic fundamentals of a sovereign significantly affect the bond yield spread, the market's attitude towards risk is another important determinant. We construct a measure of the market's attitude towards risk called the risk appetite index

In-Mee Baek; Arindam Bandopadhyaya; Chan Du

2005-01-01

72

On the significance of the economic determinants of systematic risk: empirical evidence with Finnish data  

Microsoft Academic Search

The individual and incremental information content of different economic determinants of common stock systematic risk is determined in the Finnish stock market. Based on previous theoretical articles, four financial characteristics of a firm are investigated: profitability, financial leverage, operating leverage, and corporate growth, measured as growth in earnings and dividends. In three of the four subperiods, the most important factor

Teppo Martikainen

1991-01-01

73

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

74

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

75

Economics.  

ERIC Educational Resources Information Center

This issue focuses on the theme of economics, and presents educational resources for teaching basics to children. Web sites, CD-ROMs and software, videos, books, and additional resources, as well as activities which focus on economics are described. Includes short features on related topics, and the subtopics of trade, money and banking, and…

Online-Offline, 1998

1998-01-01

76

Assessment of the Long-Term Viability of the Myxospores of Myxobolus cerebralis as Determined by Production of the Actinospores by Tubifex tubifex.  

PubMed

While whirling disease was first observed in Rainbow Trout Oncorhynchus mykiss in 1893, the complete life cycle of Myxobolus cerebralis (Mc), the causative agent of the disease, was not understood until 1984, when it was shown to involve two obligate hosts, a salmonid fish and the aquatic oligochaete Tubifex tubifex (Tt). The viability of the triactinomyxon (TAM) actinospores produced by Tt has been well studied, and is known to be temperature dependent and measured in days and weeks. Assertions that Mc myxospores produced by infected fish remain viable for years or even decades were made during the mid-20th century, decades before the Mc life cycle was described. Moreover, the duration of myxospore viability has not been well studied since the life cycle was elucidated. In a series of time-delay treatments, we assessed the long-term viability of Mc myxospores by exposure to Mc-susceptible Tt oligochaetes and quantified TAM production. As the time delay between inoculation and incubation of Mc myxospores in sand and water and exposure to Tt oligochaetes increased, TAM production decreased exponentially. Production among the 15-d time-delay replicates was reduced 74.7% compared with the 0-d treatment. Likewise, total TAM production was reduced 94.5, 99.4, and 99.9%, respectively, in the 90-, 120-, and 180-d time-delay treatments. Linear regression analysis of our data and the absence of TAM production among replicates of Mc myxospores held at 5°C for 365 d prior to exposure to Mc-susceptible Tt oligochaetes indicate that the long-term viability of Mc myxospores is less than 1 year under the conditions of this study. Received May 14, 2014; accepted September 27, 2014. PMID:25706032

Nehring, R Barry; Schisler, George; Chiaramonte, Luciano; Horton, Annie; Poole, Barbara

2015-03-01

77

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

78

Viability of bacteria in peatlands  

NASA Astrophysics Data System (ADS)

The viability of bacteria in oligotrofic bogs and fens was determined by the luminescent microscopy method with the help of a two-component fluorescent dye (L7012 LIVE/DEAD). Living bacterial cells were found in the entire peat profiles. Their portion was maximal (up to 60%) in the upper layers and did not exceed 25% in the lower layers. The portion of dead bacterial cells varied from 3 to 19%, and dormant cells constituted 25 to 95% of the total number of bacterial cells. The numbers of dormant cells increased down the profiles irrespectively of the peat type. The portion of nanoforms did not exceed 5% of the total. The cells of the nanoforms, unlike the bacteria of typical sizes, were characterized by their high viability (93-98%).

Bogdanova, O. Yu.; Golovchenko, A. V.; Lysak, L. V.; Glukhova, T. V.; Zvyagintsev, D. G.

2014-04-01

79

Oil Production in the Lower 48 States: Economic, Geological, and Institutional Determinants  

Microsoft Academic Search

In this paper, we establish an empirical model for oil production in the lower 48 states that represents its economic, physical, and institutional determinants. We estimate a vector error correction model for oil production in the lower 48 states that specifies real oil prices, average production costs, and prorationing by the Texas Railroad Commission. These modifications enable us to generate

Robert K. Kaufmann; Cutler J. Cleveland

2001-01-01

80

Understanding School Choice: Location as a Determinant of Charter School Racial, Economic, and Linguistic Segregation  

ERIC Educational Resources Information Center

The author analyzes the revealed school preferences of parents in the Washington, D.C., and asks, "What is the main determinant of charter school choice and how does it create racial, economic, and linguistic segregation?" The author first establishes a theory of choice, which incorporates past research and adds an additional variable to our…

Jacobs, Nicholas

2013-01-01

81

The economic and demographic determinants of international migration in Rural Egypt  

Microsoft Academic Search

This study uses data collected in rural Egypt to estimate a micro?level model of the economic and demographic determinants of international migration. This model uses predicted income functions to establish origin incomes (incomes excluding remittances). Three findings are noteworthy. First, the results suggest that education may not necessarily be positively correlated with migration. Second, the data indicate that the relationship

Richard H. Adams Jr

1993-01-01

82

How Do States Formulate Medicaid and SCHIP Policy? Economic and Political Determinants of State Eligibility Levels  

Microsoft Academic Search

We exploit the existence of substantial variation in state policies toward public health insurance for children between 1990 and 2002 to estimate the economic and political determinants of state eligibility levels. Controlling for state and year effects, eligibility levels are not significantly associated with either the percentage of uninsured children in the state or the eligibility policy of neighboring states;

Jeffrey Milyo; Reagan Baughman

2008-01-01

83

Political and economic determinants of budget deficits in the industrial democracies  

Microsoft Academic Search

Given the large deficits in many OECD countries in recent years, and the resulting sharp rise in the public debt, it is important to determine the economic and political forces leading to such large deficits. We lind only partial support for the 'equilibrium approach to liscal policy', which assumes that tax rates are set over time in order to minimize

Nouriel Roubini; Jeffrey D. Sachs

1989-01-01

84

Economic viability of rangeland based ranching enterprises  

E-print Network

and to the study results. Results suggest in a market in which stocker cows are bought or sold at the same price, overall expected net returns from using seasonal climate forecasts are negative. A decrease in net returns does not necessarily imply the value...

Jochec, Kristi Gayle

2000-01-01

85

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

86

Health care utilization in Ecuador: a multilevel analysis of socio-economic determinants and inequality issues.  

PubMed

This article examines socio-economic determinants and inequality of health care utilization in Ecuador. Despite health reform efforts in Latin America, drastic socio-economic inequalities persist across the region, including Ecuador. Almost a third of Ecuador's population lack regular access to health services, while more than two-thirds have no health insurance and insufficient resources to pay for health care services. Using Andersen's model of health care utilization behaviour, relevant variables were selected from the 2004 National Demographic and Maternal & Child Health Survey (ENDEMAIN) household survey. Four outcomes were assessed: use of preventive services, number of curative visits, hospitalization, and use of antiparasitic medicines. Adjusting for various predisposing, enabling and need factors, a significant negative relationship was found between household economic status (as measured by assets and consumption quintiles) and utilization of preventive and curative services. The same was true for use of antiparasitic medicines. Further, indigenous ethnicity was found to be a significant negative predictor of health care utilization, regardless of economic status. These socio-economic inequalities in the use of health care services suggest the need for health care reform in Ecuador to address these issues more systematically. It is necessary for public health authorities to move forward on a reform that will expand coverage, particularly to indigenous and low- and middle-income households. PMID:19917653

López-Cevallos, Daniel F; Chi, Chunhuei

2010-05-01

87

Economic inequality in eye care utilization and its determinants: a Blinder–Oaxaca decomposition  

PubMed Central

Background: The current study aimed to determine eye care utilization, to assess the role of economic inequality in the utilization of eye care services, and to identify its determinants in Shahroud, North of Iran. Methods: Of the 6,311 invited people, 5,190 (82.24%) individuals aged 40 to 64 years old participated in the study. A history of a visit by an ophthalmologist or optometrist was considered as eye care utilization. The gap between low- and high-economic groups was decomposed into its determinants using the Oaxaca decomposition method. Results: Among the participants, 16.32% [95% Confidence Intervals (CI)= 15.31–17.33%] had never been examined by an ophthalmologist or optometrist, and 30.94% (95% CI= 29.69–32.20%) had not undergone an eye examination in the past 5 years. This negative history was significantly higher among female subjects [Odds Ratio (OR)= 1.79, 95% CI= 1.51–2.14], the low-economic group (OR= 2.33, 95% CI= 1.90–2.87), the visually impaired (OR= 1.41, 95% CI= 1.05–1.90), and the uninsured (OR= 1.93, 95% CI= 1.45–2.58). The negative history of eye examination decreased with increasing in age (OR= 0.94, 95% CI= 0.93–0.96) and education (OR= 0.94, 95% CI= 0.92–0.96). In this study, 24.72% (95% CI= 22.30–27.14) of the low-economic group and 9.94% (95% CI= 8.75–11.14) of the high-economic group had no history of eye examination. Decomposition of the gap between the two economic groups showed that education and gender were the most important determinants of inequality. Conclusion: A considerable percentage of adults, even those with visual impairment, do not receive appropriate eye care. There is a definite economic inequality in the community for which poverty per se could be the major cause. PMID:25396206

Emamian, Mohammad Hassan; Zeraati, Hojjat; Majdzadeh, Reza; Shariati, Mohammad; Hashemi, Hassan; Fotouhi, Akbar

2014-01-01

88

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

SciTech Connect

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

Brunner, Norbert, E-mail: norbert.brunner@cemds.org [Center for Environmental Management and Decision Support, Gregor Mendel Str. 33, A-1180 Vienna (Austria); Starkl, Markus, E-mail: markus.starkl@boku.ac.at [Competence Centre for Decision-Aid in Environmental Management, University of Natural Resources and Life Sciences/DIB, Gregor Mendel Strasse 33, 1180 Wien (Austria)

2012-01-15

89

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. PMID:23786633

2013-01-01

90

CYTOCHEMICAL METHODS FOR ASSESSING 'GIARDIA' CYST VIABILITY  

EPA Science Inventory

Giardia lamblia is the most common human intestinal protozoan parasite reported in the United States and England. The objective of the study was to develop a practical, reliable, rapid, microscopically-read method, comparable to excystation for determining the viability of Giardi...

91

EFFECT OF HALOGENS ON 'GIARDIA' CYST VIABILITY  

EPA Science Inventory

The objective of this research was to determine the effect of chlorine and other disinfecting agents on Giardia lamblia cyst viability. The agents studied included free residual chlorine and six different methods recommended for emergency disinfection of small quantities of water...

92

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

ERIC Educational Resources Information Center

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

Bailey, Lora Battle

2006-01-01

93

Determining Employment Needs, Educational Feasibilities, and Potential Enrollments in Occupational Home Economics at the Post-Secondary Level in Oklahoma.  

ERIC Educational Resources Information Center

In order to determine if occupationally-oriented curriculums in home economics should be developed at the post-secondary level in Oklahoma, three groups of people were interviewed: (1) managers of business establishments and supervisors of child care agencies, (2) administrators and instructors of home economics courses, and (3) students enrolled…

Robinson, Lillie McCray

94

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

E-print Network

's cognitive development(8,9) . Needless to say, poor socio-economic status is a strong inhibitor limitingNutritional and socio-economic determinants of cognitive function and educational achievement influencing the cognitive function and educational achievement of these children. Cognitive function

Paris-Sud XI, Université de

95

Spatial variation and socio-economic determinants of Plasmodium falciparum infection in northeastern Tanzania  

Microsoft Academic Search

Background  Malaria due to Plasmodium falciparum is the leading cause of morbidity and mortality in Tanzania. According to health statistics, malaria accounts for about 30%\\u000a and 15% of hospital admissions and deaths, respectively. The risk of P. falciparum infection varies across the country. This study describes the spatial variation and socio-economic determinants of P. falciparum infection in northeastern Tanzania.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  The study

Bruno P Mmbando; Mathias L Kamugisha; John P Lusingu; Filbert Francis; Deus S Ishengoma; Thor G Theander; Martha M Lemnge; Thomas H Scheike

2011-01-01

96

Viability and Resilience of Languages in Competition  

PubMed Central

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

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

2010-01-01

97

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

98

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

99

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

PubMed Central

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

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

2014-01-01

100

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

PubMed Central

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

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

2012-01-01

101

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

102

Cost and Economics for Advanced Launch Vehicles  

NASA Technical Reports Server (NTRS)

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

Whitfield, Jeff

1998-01-01

103

Infrared spectroscopy of plant cell cultures : noninvasive measurement of viability.  

PubMed

Infrared spectroscopy was used to examine suspension-cultured pear (Pyrus communis L.) and Spartina pectinata cells. Noninvasive measurements were made using internal reflectance sampling. Spectra of actively growing cells exhibited a pronounced absorbance at 2343 reciprocal centimeters. The absorbance peak was identified and verified as CO(2) dissolved in water. This peak was absent in nonviable cells. Peak height was directly proportional to percent viability in artificial mixtures of viable and nonviable cells, indicating that the level of intracellular CO(2) production could be used as a viability determinant for plant cells. Suspension-cultured cells were slowly cooled to subzero temperatures and analyzed for viability using infrared spectroscopy and tetrazolium staining. Both methods showed similar trends in viability assessment. Infrared spectroscopy could provide a more detailed understanding of cell viability and allow measurement on a noninvasive basis. PMID:16668026

Sowa, S; Towill, L E

1991-02-01

104

Socio-economic determinants of fertility in some countries of Asia.  

PubMed

An attempt is made in this analysis to determine the individual contribution of 6 factors--health variables, educational variables, variables showing status of women, economic variables, modernization variables, and family planning program performance variables--in determining the level of fertility on the basis of available data for 13 Asian countries. Path analysis and stepwise regression analysis were used. The pattern of the interrelationship between different categories of the variables which are affecting fertility and family planning performance are schematically represented in a chart. The model assumes that socioeconomic development of a country is a precondition for further mortality and fertility decline. The application of the model to any empirical situation calls for the determination of the indicators of the output variable (fertility) and other explanatory factors such as socioeconomic development, modernization, and health variables. For this study only 13 developing countries with 11 variables that are highly correlated with the fertility variables for the year 1975 were selected. 2 measures of fertility, i.e., total fertility rate (TFR) and crude birthrate (CBR) were taken for the purpose of the analysis and are denoted by Xo. The important background variables linked to fertility decline were literacy, urbanization, gross national product (GNP) per capita, and economically active female population in that order. Infant mortality and family planning were the most proximate variables to fertility. One of the reasons that fertility levels varied among the countries was that most of the countries have not as yet crossed the lower limits of the threshold zones with respect to most of the indicators. Except for 3 or 4 of the countries, none of the countries had entered the threshold zone for all the indicators. Particularly countries like Bangladesh, Nepal, and Pakistan were far below the lower limit of threshold zone in respect to all of the indicators, and in these countries the fertility declines were very low. Countries like Hong Kong, Korea, Malaysia, and Singapore had already crossed the threshold zones for almost all of the indicators, and there has been a rapid decline in fertility in these countries. Countries like Sri Lanka and the Philippines have entered the threshold zone only for some of the indicators and hence experienced only moderate fertility decline. As the data used for the analysis are of limited reliability, the findings should be taken only as tentative. PMID:12339046

Pathak, K B; Murty, P K

1982-06-01

105

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

PubMed Central

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

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

2014-01-01

106

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

PubMed

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

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

2014-05-01

107

Socio-Economic and Nutritional Determinants of Low Birth Weight in India  

PubMed Central

Background: Low birth weight (LBW) is an important risk factor for childhood morbidity and mortality, consequently an important public health concern. Aim: This study aims to identify significant socio-economic and nutritional determinants associated with LBW in India. Materials and Methods: Data from 2005 to 2006 National Family Health Survey-3 (NFHS-3) of India was analyzed. A total of 20,946 women (15-49 years) who gave birth at least once 5 years preceding the NFHS-3 were included in this study. Infant's LBW (<2500 grams) as outcome variable was examined in association with all independent predictors as infant's sex, maternal household wealth status, caste, age, education, body mass index (BMI), stature, anemia level, parity, inter-pregnancy interval, antenatal care received, and living place. Results: Almost 20% of the infants were born with LBW. Mother's low education level, BMI <18.5, short stature (height <145 centimeters) and lack of antenatal visits (<4 visits) were significant predictors of LBW. Male gender has a protective effect against LBW. Conclusion: Maternal education, nutritional status and antenatal care received are key determinants that need to be addressed to reduce prevalence of LBW in India. Continue implementation of multifaceted health promotion interventions are needed to address these factors effectively. PMID:25077077

Kader, Manzur; Perera, Nirmala K P Perera

2014-01-01

108

A new procedure to asses pollen viability  

Microsoft Academic Search

We tested pollen viability of eight species using four vital dyes, a new peroxidase test together with three other established\\u000a methods (MTT, Baker’s and X-Gal), to determine their potential to differentiate fresh pollen from pollen heated for 2 h and\\u000a 24 h at 80°C (killed pollen) and compared the results with in vitro germination. We found that two of three

T. Rodriguez-Riano; A. Dafni

2000-01-01

109

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

PubMed Central

Background Malaria transmission is influenced by variations in meteorological conditions, which impact the biology of the parasite and its vector, but also socio-economic conditions, such as levels of urbanization, poverty and education, which impact human vulnerability and vector habitat. The many potential drivers of malaria, both extrinsic, such as climate, and intrinsic, such as population immunity are often difficult to disentangle. This presents a challenge for the modelling of malaria risk in space and time. Methods A statistical mixed model framework is proposed to model malaria risk at the district level in Malawi, using an age-stratified spatio-temporal dataset of malaria cases from July 2004 to June 2011. Several climatic, geographic and socio-economic factors thought to influence malaria incidence were tested in an exploratory model. In order to account for the unobserved confounding factors that influence malaria, which are not accounted for using measured covariates, a generalized linear mixed model was adopted, which included structured and unstructured spatial and temporal random effects. A hierarchical Bayesian framework using Markov chain Monte Carlo simulation was used for model fitting and prediction. Results Using a stepwise model selection procedure, several explanatory variables were identified to have significant associations with malaria including climatic, cartographic and socio-economic data. Once intervention variations, unobserved confounding factors and spatial correlation were considered in a Bayesian framework, a final model emerged with statistically significant predictor variables limited to average precipitation (quadratic relation) and average temperature during the three months previous to the month of interest. Conclusions When modelling malaria risk in Malawi it is important to account for spatial and temporal heterogeneity and correlation between districts. Once observed and unobserved confounding factors are allowed for, precipitation and temperature in the months prior to the malaria season of interest are found to significantly determine spatial and temporal variations of malaria incidence. Climate information was found to improve the estimation of malaria relative risk in 41% of the districts in Malawi, particularly at higher altitudes where transmission is irregular. This highlights the potential value of climate-driven seasonal malaria forecasts. PMID:24228784

2013-01-01

110

Low-level waste vitrification contact maintenance viability study  

SciTech Connect

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

Leach, C.E., Westinghouse Hanford

1996-07-12

111

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

NASA Technical Reports Server (NTRS)

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

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

1996-01-01

112

The influence of socio-demographic indicators economic determinants and social recognition on sport participation in Germany.  

PubMed

This article analyses sport participation using a demographic-economic model which was extended by the construct 'social recognition'. Social recognition was integrated into the model on the understanding that it is the purpose of each individual to maximise his or her utility. A computer-assisted telephone interview survey was conducted in the city of Rheinberg, Germany, producing an overall sample of n=1934. Regression analyses were performed to estimate the impact of socio-demographic, economic determinants, and social recognition on sport participation. The results suggest that various socio-economic factors and social recognition are important determinants of sport participation on the one hand, and on sport frequency on the other. Social recognition plays a significant yet different role for both sport participation and sport frequency. While friends' involvement with sport influences one's sport participation, parents' involvement with sport influences one's sport frequency. PMID:24444226

Hallmann, Kirstin; Breuer, Christoph

2014-01-01

113

Economic Value of Timely Determination of Unexpected Decreases in Detection of Estrus Using Control Charts1  

Microsoft Academic Search

Total economic effects of decreased estrus detection efficiency (EDE) are a function of the economic loss per day and the length of the decrease. A stochastic dynamicdairyherdsimulationmodelwasusedtodeter- mine whether estimates from permanently different EDE rates in herds of 100 and 1000 cows could approxi- mate net returns due to temporary decreases in EDE. The default EDE was 65% and was

A. de Vries; B. J. Conlin

2003-01-01

114

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

115

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

116

JOINT DETERMINATION OF OPTIMUM PROCESS MEAN AND ECONOMIC SPECIFICATION LIMITS FOR RECTIFYING INSPECTION PLAN WITH INSPECTION ERROR  

Microsoft Academic Search

In 2006, Chen presented a modified Pulak and Al-Sultan's model with quadratic quality loss function of product within the specification limits for determining the optimum process parameters. However, he did not consider the problem of inspection error. In this paper, the authors propose an integrated model for obtaining the optimum process mean and economic specification limits based on the modified

Chung-Ho Chen; Michael B. C. Khoo

2008-01-01

117

Gender and viability selection on morphology in fledgling pied flycatchers  

Microsoft Academic Search

Until recently, analyses of gender-dependent differences in viability selection and the ontogeny of sexual size dimorphism have been plagued by difficulties in determining the sex of nestling birds on the basis of morphology. Recently, this problem was overcome using molecular sex identification to report for the first time body-size-mediated anta- gonistic selection on the viability of male and female collared

J. Potti; J. A. Davila; J. L. Tella; O. Frias; S. Villar

2002-01-01

118

Determining Expressed Inservice Needs of Wisconsin Secondary and Post-Secondary Vocational, Technical, and Adult Education Teachers in Home Economics Related Areas. Final Report.  

ERIC Educational Resources Information Center

A study was conducted to determine the felt needs of Wisconsin home economics teachers for inservice education as a basis for designing educational programs to meet these needs. The population consisted of 1,278 home economics public school teachers and 1,430 vocational, technical, and adult education (VTAE) teachers of home economics related…

Hughes, Lois; Dougherty, Barbara

119

Coal-fueled diesel locomotive economic assessment  

SciTech Connect

This report presents an initial effort in determining the eonomic viability of a coal-fueled diesel locomotive for the time period 1995 to 2010. The criteria used for determining the economic viability of a coal-fueled diesel is the internal rate of return on investment (IRR). The coal-fueled diesel locomotive is compared to a baseline petroleum-fueled diesel. The coal-fueled diesel locomotive is still very much conceptual, therefore many assumptions are made with regard to cost, operating procedure, fuel form, fuel cost, maintenance, etc. The assumptions are discussed and the spreadsheet calculation procedure used for determining the IRR is presented. Conclusions based on the assumptions and calculations are given.

Not Available

1986-10-01

120

A rapid, sensitive, and cost-efficient assay to estimate viability of potato cyst nematodes.  

PubMed

Potato cyst nematodes (PCNs) are quarantine organisms, and they belong to the economically most relevant pathogens of potato worldwide. Methodologies to assess the viability of their cysts, which can contain 200 to 500 eggs protected by the hardened cuticle of a dead female, are either time and labor intensive or lack robustness. We present a robust and cost-efficient viability assay based on loss of membrane integrity upon death. This assay uses trehalose, a disaccharide present at a high concentration in the perivitelline fluid of PCN eggs, as a viability marker. Although this assay can detect a single viable egg, the limit of detection for regular field samples was higher, ?10 viable eggs, due to background signals produced by other soil components. On the basis of 30 nonviable PCN samples from The Netherlands, a threshold level was defined (?A(trehalose) = 0.0094) below which the presence of >10 viable eggs is highly unlikely (true for ?99.7% of the observations). This assay can easily be combined with a subsequent DNA-based species determination. The presence of trehalose is a general phenomenon among cyst nematodes; therefore, this method can probably be used for (for example) soybean, sugar beet, and cereal cyst nematodes as well. PMID:21942733

van den Elsen, Sven; Ave, Maaike; Schoenmakers, Niels; Landeweert, Renske; Bakker, Jaap; Helder, Johannes

2012-02-01

121

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

SciTech Connect

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

Olsen, D.R.

1997-07-13

122

Pneumocystis Melanins Confer Enhanced Organism Viability  

PubMed Central

Pneumocystis continues to represent an important opportunistic fungal pathogen of those with compromised immunity. Thus, it is crucial to identify factors that affect its viability and pathogenicity. We previously reported the first identification of melanins in Pneumocystis. In the present study, we sought to further characterize these components and define the function for these melanins. Melanins extracted from Pneumocystis and melanized Pneumocystis cells were analyzed by electron spin resonance spectroscopy, revealing spectra consistent with melanins from other fungi. Immunofluorescence assays using anti-melanin monoclonal antibodies showed that melanins are widely present across Pneumocystis host species, including mouse-, ferret-, and human-derived Pneumocystis organisms, as well as Pneumocystis carinii derived from rat. Using immunoelectron microscopy, melanins were found to localize to the cell wall and cytoplasm of P. carinii cysts, as well as to intracystic bodies within mature cysts. Next, the role of melanins on the maintenance of Pneumocystis viability was determined by using quantitative reverse transcription-PCR measurement of the heat shock protein mRNA under adverse environmental conditions. Using a new method to promote the melanization of Pneumocystis, we observed that strongly melanized Pneumocystis retained viability to a greater degree when exposed to UV irradiation or desiccation compared to less-pigmented organisms. These studies support our previous identification of Pneumocystis melanins across the genus, further characterize these Pneumocystis components, and demonstrate that melanins protect Pneumocystis from environmental stressors. PMID:16757739

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

2006-01-01

123

Stochastic viability and dynamic programming  

E-print Network

This paper deals with the stochastic control of nonlinear systems in the presence of state and control constraints, for uncertain discrete-time dynamics in finite dimensional spaces. In the deterministic case, the viability kernel is known to play a basic role for the analysis of such problems and the design of viable control feedbacks. In the present paper, we show how a stochastic viability kernel and viable feedbacks relying on probability (or chance) constraints can be defined and computed by a dynamic programming equation. An example illustrates most of the assertions.

Doyen, Luc

2010-01-01

124

Seminal Fluid Affects Sperm Viability in a Cricket  

PubMed Central

Recent studies have suggested that males may vary the quality of their ejaculates in response to sperm competition, although the mechanisms by which they do so remain unclear. The viability of sperm is an important aspect of ejaculate quality that determines competitive fertilization success in the field cricket Teleogryllus oceanicus. Using in vitro mixtures of sperm and seminal fluid from pairs of male crickets, we show that seminal fluid can affect the viability of sperm in this species. We found that males who invest greatly in the viability of their own sperm can enhance the viability of rival sperm, providing the opportunity for males to exploit the investments in sperm competition made by their rivals. Transitive effects of seminal fluids across the ejaculates of different males are expected to have important implications for the dynamics of male investments in sperm competition. PMID:21455309

Simmons, Leigh W.; Beveridge, Maxine

2011-01-01

125

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

PubMed Central

Background Governments have been implementing policies aimed at halting the trend towards early retirement for Baby Boomers. Public policies can have a strong effect on when a person retires and this analysis contributes to an improved understanding of retirement aspirations in regards to health, social, workplace and economic determinants. Methods In October 2011 a telephone survey was undertaken with participants aged 50 to 65 years who were in paid employment and who had been in the workforce for the previous three years. Participants were obtained from two identical South Australian cohort studies - the North West Adelaide Health Study and the Florey Adelaide Male Ageing Study. The results of the telephone survey were linked to the original cohort data. Data were weighted by sex, age, postcode and probability of selection in the household. Work related questions included how much they thought about their retirement, current occupation, employment status, type of workplace and hours worked per week. Health related questions included current smoking status, physical activity, body mass index, self-reported health status and overall life satisfaction. Uni-variable and multi-variable analyses were undertaken to compare the different associations between people who were and were not intending to retire. Results In total, 25.9% (n?=?210) of people who were currently in paid employment indicated that they intend to retire completely from the workforce. The remainder indicated that they will continue to work (41.8% retire from full-time work but work part-time, 25.7% continue working part-time but reduce their current hours, and 6.7% never retire). The multi-variable results indicate that those with lower education, having a savings habit, and sales workers more likely to anticipate complete retirement. The self-employed, and those thinking only moderately about retirement, were more likely to extend their working life beyond age 65. Conclusion An important finding of this study is the large number of Baby Boomers who indicated that they would be happy to work part-time or never retire. Policies and continued dialogue aimed at making the workplace a safe, flexible and welcoming environment to accommodate this wish, and to entice others to take up this option over complete withdrawal from the labour force, is required. PMID:24731726

2014-01-01

126

HEALTH DISPARITIES IN LATIN AMERICA AND THE CARIBBEAN: THE ROLE OF SOCIAL AND ECONOMIC DETERMINANTS  

Microsoft Academic Search

parities either between or within countries. Rather, improvements appear to be dispropor- tionately weighted toward those who already have a greater share of social and economic advantages in society, while the health of dis- advantaged groups improves less consistently and at much more modest rates.

Juan Antonio Casas; J. Norberto; W. Dachs; Alexandra Bambas

127

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

128

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

129

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

130

HOUSEHOLD ECONOMIC RESOURCES AS A DETERMINANT OF CHILDHOOD NUTRITION: POLICY RESPONSES FOR NEW ZEALAND  

Microsoft Academic Search

Improving the nutrition of children and reducing rates of childhood overweight and obesity have been high priorities for the New Zealand Government since 2000. The rates of childhood overweight and obesity vary by ethnic group and socio-economic status, and reducing inequalities in the burden of childhood overweight and obesity is an explicit aim of the Government. This paper aims to

Mat Walton; Louise Signal; George Thomson

131

The theory of economic regulation and public choice and the determinants of public sector bargaining legislation  

Microsoft Academic Search

In this study we used the theory of economic regulation and public choice to derive a model to explain the pattern of public sector bargaining laws among the states. We find this type of legislation is influenced by the following demand factors: (1) the extent of public sector union membership, which represents the interest group hypothesis, has a positive influence

Melissa Waters; William J. Moore

1990-01-01

132

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

ERIC Educational Resources Information Center

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

Jagodzinski, Wolfgang

2010-01-01

133

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

134

Relationship between extent of residual myocardial viability and coronary flow reserve in patients with recent myocardial infarction  

Microsoft Academic Search

Background The presence of viability in an infarct zone implies an intact microvasculature. We hypothesized that coronary flow reserve (CFR), which assesses the microcirculation, would correlate with the extent of viability in infarction zones. Methods CFR was measured after stenting in 17 patients with single vessel disease >48 hours from infarction. Viability was determined with use of single-photon emission computed

Michael Ragosta; Eric R. Powers; Habib Samady; Lawrence W. Gimple; Ian J. Sarembock; George A. Beller

2001-01-01

135

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

136

A regional IT occupational partnership for economic development  

Microsoft Academic Search

Increasingly, the economic viability of regions, states and countries is being linked to the viability of technology-enabled, knowledge-intensive economic sectors. Hence, among the factors of interest in regional economic development is the availability of an information technology (IT) talent pool. There is a growing need to understand the regional supply and demand dynamics of appropriately educated IT professionals. Consequently, an

Eileen M. Trauth; Mike Reinert; Michael C. Zigner

2007-01-01

137

The market viability of nuclear hydrogen technologies.  

SciTech Connect

The Department of Energy Office of Nuclear Energy is supporting system studies to gain a better understanding of nuclear power's potential role in a hydrogen economy and what hydrogen production technologies show the most promise. This assessment includes identifying commercial hydrogen applications and their requirements, comparing the characteristics of nuclear hydrogen systems to those market requirements, evaluating nuclear hydrogen configuration options within a given market, and identifying the key drivers and thresholds for market viability of nuclear hydrogen options. One of the objectives of the current analysis phase is to determine how nuclear hydrogen technologies could evolve under a number of different futures. The outputs of our work will eventually be used in a larger hydrogen infrastructure and market analysis conducted for DOE-EE using a system-level market simulation tool now underway. This report expands on our previous work by moving beyond simple levelized cost calculations and looking at profitability, risk, and uncertainty from an investor's perspective. We analyze a number of technologies and quantify the value of certain technology and operating characteristics. Our model to assess the profitability of the above technologies is based on Real Options Theory and calculates the discounted profits from investing in each of the production facilities. We use Monte-Carlo simulations to represent the uncertainty in hydrogen and electricity prices. The model computes both the expected value and the distribution of discounted profits from a production plant. We also quantify the value of the option to switch between hydrogen and electricity production in order to maximize investor profits. Uncertainty in electricity and hydrogen prices can be represented with two different stochastic processes: Geometric Brownian Motion (GBM) and Mean Reversion (MR). Our analysis finds that the flexibility to switch between hydrogen and electricity leads to significantly different results in regards to the relative profitability of the different technologies and configurations. This is the case both with a deterministic and a stochastic analysis, as shown in the tables below. The flexibility in output products clearly adds substantial value to the HPE-ALWR and HTE-HTGR plants. In fact, under the GBM assumption for prices, the HTE-HTGR plant becomes more profitable than the SI-HTGR configuration, although SI-HTGR has a much lower levelized cost. For the HTE-HTGR plant it is also profitable to invest in additional electric turbine capacity (Case b) in order to fully utilize the heat from the nuclear reactor for electricity production when this is more profitable than producing hydrogen. The technologies are all at the research and development stage, so there are significant uncertainties regarding the technology cost and performance assumptions used in this analysis. As the technologies advance, the designers need to refine the cost and performance evaluation to provide a more reliable set of input for a more rigorous analysis. In addition, the durability of the catalytic activity of the materials at the hydrogen plant during repetitive price cycling is of prime importance concerning the flexibility of switching from hydrogen to electricity production. However, given the potential significant economic benefit that can be brought from cogeneration with the flexibility to quickly react to market signals, DOE should consider R&D efforts towards developing durable materials and processes that can enable this type of operation. Our future work will focus on analyzing a range of hydrogen production technologies associated with an extension of the financial analysis framework presented here. We are planning to address a variety of additional risks and options, such as the value of modular expansion in addition to the co-generation capability (i.e., a modular increase in the hydrogen production capacity of a plant in a given market with rising hydrogen demand), and contrast that with economies-of-scale of large-unit designs.

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

2007-04-06

138

Clinical Evaluation of Tuberculosis Viability Microscopy for Assessing Treatment Response  

PubMed Central

Background.?It is difficult to determine whether early tuberculosis treatment is effective in reducing the infectiousness of patients' sputum, because culture takes weeks and conventional acid-fast sputum microscopy and molecular tests cannot differentiate live from dead tuberculosis. Methods.?To assess treatment response, sputum samples (n = 124) from unselected patients (n = 35) with sputum microscopy–positive tuberculosis were tested pretreatment and after 3, 6, and 9 days of empiric first-line therapy. Tuberculosis quantitative viability microscopy with fluorescein diacetate, quantitative culture, and acid-fast auramine microscopy were all performed in triplicate. Results.?Tuberculosis quantitative viability microscopy predicted quantitative culture results such that 76% of results agreed within ±1 logarithm (rS = 0.85; P < .0001). In 31 patients with non-multidrug-resistant (MDR) tuberculosis, viability and quantitative culture results approximately halved (both 0.27 log reduction, P < .001) daily. For patients with non-MDR tuberculosis and available data, by treatment day 9 there was a >10-fold reduction in viability in 100% (24/24) of cases and quantitative culture in 95% (19/20) of cases. Four other patients subsequently found to have MDR tuberculosis had no significant changes in viability (P = .4) or quantitative culture (P = .6) results during early treatment. The change in viability and quantitative culture results during early treatment differed significantly between patients with non-MDR tuberculosis and those with MDR tuberculosis (both P < .001). Acid-fast microscopy results changed little during early treatment, and this change was similar for non-MDR tuberculosis vs MDR tuberculosis (P = .6). Conclusions.?Tuberculosis quantitative viability microscopy is a simple test that within 1 hour predicted quantitative culture results that became available weeks later, rapidly indicating whether patients were responding to tuberculosis therapy. PMID:25537870

Datta, Sumona; Sherman, Jonathan M.; Bravard, Marjory A.; Valencia, Teresa; Gilman, Robert H.; Evans, Carlton A.

2015-01-01

139

Effect of extracorporeal shock wave lithotripsy on bacterial viability  

Microsoft Academic Search

The aim of this study was to determine whether extracorporeal shock wave lithotripsy (ESWL) affected the viability of the infecting bacteria within a simulated struvite stone matrix. A strain, Proteus mirabilis 28cii, was prepared in three forms: (1) suspended in saline and urine, (2) artificially encapsulated by suspending in agar beads and (3) artificially encapsulated and mineralised by suspending in

G. Reid; M. A. S. Jewett; J. C. Nickel; R. J. C. McLean; A. W. Bruce

1990-01-01

140

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. PMID:23245431

2012-01-01

141

Socio-economic and demographic determinants of under-five mortality in rural northern Ghana  

PubMed Central

Background In spite of global decline in under-five mortality, the goal of achieving MDG 4 still remains largely unattained in low and middle income countries as the year 2015 closes-in. To accelerate the pace of mortality decline, proven interventions with high impact need to be implemented to help achieve the goal of drastically reducing childhood mortality. This paper explores the association between socio-economic and demographic factors and under-five mortality in an impoverished region in rural northern Ghana. Methods We used survey data on 3975 women aged 15–49 who have ever given birth. First, chi-square test was used to test the association of social, economic and demographic characteristics of mothers with the experience of under-five death. Subsequently, we ran a logistic regression model to estimate the relative association of factors that influence childhood mortality after excluding variables that were not significant at the bivariate level. Results Factors that significantly predict under-five mortality included mothers’ educational level, presence of co-wives, age and marital status. Mothers who have achieved primary or junior high school education were 45% less likely to experience under-five death than mothers with no formal education at all (OR = 0.55, p < 0.001). Monogamous women were 22% less likely to experience under-five deaths than mothers in polygamous marriages (OR = 0.78, p = 0.01). Similarly, mothers who were between the ages of 35 and 49 were about eleven times more likely to experience under-five deaths than those below the age of 20 years (OR = 11.44, p < 0.001). Also, women who were married had a 27% less likelihood (OR = 0.73, p = 0.01) of experiencing an under-five death than those who were single, divorced or widowed. Conclusion Taken independently, maternal education, age, marital status and presence of co-wives are associated with childhood mortality. The relationship of these indicators with women’s autonomy, health seeking behavior, and other factors that affect child survival merit further investigation so that interventions could be designed to foster reductions in child mortality by considering the needs and welfare of women including the need for female education, autonomy and socioeconomic well-being. PMID:25145383

2014-01-01

142

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

PubMed

Of all the food additives for which the FDA has received adverse reaction reports, the ones that most closely resemble true allergens are sulfur-based preservatives. Sulfites are used primarily as antioxidants to prevent or reduce discoloration of light-colored fruits and vegetables, such as dried apples and potatoes, and to inhibit the growth of microorganisms in fermented foods such as wine. This work aims to prepare an electrochemical biosensor based on bay leaf tissue homogenate that contains polyphenol oxidase enzyme abundantly for sulfite detection in foods. The principle of the biosensor is based on the inhibition effect of sulfites on polyphenol oxidase in the bioactive layer. Optimum conditions for the biosensor, such as temperature and pH, were investigated. Some stability parameters of the biosensor were also identified. The biosensor showed a linear calibration graph in the range of 25-100 microM sulfite. The biosensor presents a very simple, economical, reliable, and feasible method for sulfite detection in foods. PMID:19418312

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

2009-01-01

143

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

SciTech Connect

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

Santini, D.J.

1987-10-01

144

Effect of storage time on the viability of cryopreserved bovine spermatozoa  

Technology Transfer Automated Retrieval System (TEKTRAN)

Long term cryopreserved semen viability can impact the National Animal Germplasm Program’s (NAGP) sampling strategy and ability to reconstitute livestock populations. Therefore, the purpose of this project was to determine if prolonged storage of cryopreserved sperm impacts cell viability. Cryoprese...

145

Socio-economic determinants for malaria transmission risk in an endemic primary health centre in Assam, India  

PubMed Central

Background Malaria is a major cause of morbidity and mortality in Northeast India. As there is limited information available on the potential influence of socio-economic variables on malaria risk, the present study was conducted to assess the influence of demographic factors, the socio-economic status, and knowledge, awareness and education on malaria occurrence. Methods Demographics, malaria knowledge and socio-economic variables were collected in four randomly selected health sub-centres of the Orang primary health centre in the Udalguri district, Assam and the association of malaria occurrence with different variables were analysed. The trend of malaria occurrence for different income groups, proximity to health centres and number of mosquito bites per day was also determined using the chi-square test. Relative risk (RR) for gender, house type, knowledge and use of bed nets was determined using Katz approximation. Results Out of the 71 household heads interviewed, 70.4% (50/71) were males. About half (54.9%, 39/71) of the participants had a history of malaria in the last two years, of which 64.1% (25/39) were males, while 35.9% (14/39) were females (?2 = 5.13; p = 0.02; RR = 1.79). Of the total population surveyed, 49.3% lived in bamboo houses and 35.2% lived at a distance of >3 km from the nearest health centre. The number of participants who had a history of malaria decreased with an increasing monthly income (p < 0.0001). Malaria occurrence was higher among the households living in bamboo houses (69.2%), as compared to Kucha houses (20.5%) and Pucca houses (10.3%). No significant association was observed between education level and malaria occurrence (p = 0.93). The participants who did not use bed nets regularly reported a high occurrence of malaria infection as compared to those who used bed nets everyday (p < 0.0001). Conclusions Lower income, house type, distance to health sub-centre, knowledge and awareness about malaria, number of mosquito bites per day and use of bed nets were positively associated with malaria occurrence. Increasing the number of health sub-centres close to rural areas, improving the economic status and increasing awareness about malaria prevention measures will thus help to reduce malaria-associated morbidities. PMID:24991410

2014-01-01

146

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

2013-01-15

147

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

PubMed Central

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

Assari, Shervin; Ahmadi, Khodabakhsh; Rezazade, Majid

2015-01-01

148

Economic viability of photovoltaic power for development assistance applications  

NASA Technical Reports Server (NTRS)

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

Bifano, W. J.

1982-01-01

149

Expanding Economic Viability for Sustainably Managed Indigenous Beech Forests  

E-print Network

BY PROJECT LEADER DR ROBERT H. DONNELLY New Zealand School of Forestry University of Canterbury Private Bag resources to co-ordinate and provide supply to meet demand. Yet NZ beech forests are 60% of the future and the U.S. The key components of the survey were NZ beech usage and future intentions

Hickman, Mark

150

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

151

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. PMID:23856321

2013-01-01

152

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

SciTech Connect

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

Whitney, Jon R [ORNL; Rodgers, Amanda [Virginia Polytechnic Institute and State University; Harvie, Erica [Virginia Polytechnic Institute and State University; Carswell, William [Virginia Polytechnic Institute and State University; Torti, Suzy [Wake Forest University, Winston-Salem; Puretzky, Alexander A [ORNL; Rouleau, Christopher M [ORNL; Geohegan, David B [ORNL; Rylander, Christopher [Virginia Polytechnic Institute and State University; Rylander, Nichole M [Virginia Polytechnic Institute and State University

2012-01-01

153

A Dynamic Programming Approach to Viability Problems  

E-print Network

A Dynamic Programming Approach to Viability Problems Pierre-Arnaud Coquelin Centre de Math kernel is the zero-level set of a related dynamic programming problem, which opens promising research directions for numerical approximation of the viability kernel using tools from approximate dynamic pro

Paris-Sud XI, Université de

154

Metabolomic Assessment of Embryo Viability  

PubMed Central

Preimplantation embryo metabolism demonstrates distinctive characteristics associated with the developmental potential of embryos. On this basis, metabolite content of culture media was hypothesized to reflect the implantation potential of individual embryos. This hypothesis was tested in consecutive studies reporting a significant association between culture media metabolites and embryo development or clinical pregnancy. The need for a noninvasive, reliable, and rapid embryo assessment strategy promoted metabolomics studies in vitro fertilization (IVF) in an effort to increase success rates of single embryo transfers. With the advance of analytical techniques and bioinformatics, commercial instruments were developed to predict embryo viability using spectroscopic analysis of surplus culture media. However, despite the initial promising results from proof-of-principal studies, recent randomized controlled trials using commercial instruments failed to show a consistent benefit in improving pregnancy rates when metabolomics is used as an adjunct to morphology. At present, the application of metabolomics technology in clinical IVF laboratory requires the elimination of factors underlying inconsistent findings, when possible, and development of reliable predictive models accounting for all possible sources of bias throughout the embryo selection process. PMID:24515909

Uyar, Asli; Seli, Emre

2014-01-01

155

Bacterial plasmolysis as a physical indicator of viability  

SciTech Connect

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 viable if they were capable of plasmolysis, as quantified by changes in cell area or light scattering. When viable Salmonella enteritidis biofilm cells were exposed to 1.5 M NaCl, and {approximately}50% reduction in cell protoplast area (as determined by high-magnification phase-contrast microscopy) was observed. In contrast, heat- and formalin-killed S. enteritidis cells were unresponsive to NaCl treatment. Furthermore, the mean dark-field cell area of a viable, sessile population of Pseudomonas fluorescens cells ({approximately}1,100 cells) increased by 50% as a result of salt stress, from 1,035 {+-} 162 to 1,588 {+-} 284 {mu}m{sup 2}, because of increased light scattering of the condensed, plasmolyzed cell protoplast. Light scattering of ethanol-killed control biofilm cells underwent little change following salt stress. When the results obtained with scanning confocal laser microscopy and a fluorescent viability probe were compared with the accuracy of plasmolysis as a viability indicator, it was found that the two methods were in close agreement. Used alone or in conjunction with fluorochemical probes, physical indicators of membrane integrity provided a rapid, direct, growth-independent method for determining the viability of biofilm bacteria known to undergo plasmolysis, and this method may have value during efficacy testing of biocides and other antimicrobial agents when nondestructive time course analyses and required. 42 refs., 7 figs.

Korber, D.R.; Choi, A.; Wolfaardt, G.M.; Caldwell, D.E. [Univ. of Saskatchewan, Saskatoon (Canada)

1996-11-01

156

Male and female effects on fertilization success and offspring viability in the Peron's tree frog, Litoria peronii  

Microsoft Academic Search

There is increasing theoretical and empirical evidence that genetic compatibility among partners is an important determinant of fertilization success and offspring viability. In amphibians, females often actively choose partners from among a variety of males and polyandry is common. Genetic compatibility among partners may therefore be an important determinant of fertilization success and offspring viability in some amphibians. Amphib- ians

CRAIG D. H. SHERMAN; ERIK WAPSTRA; TOBIAS ULLER; MATS OLSSON

2008-01-01

157

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

158

Viability of ectomycorrhizal fungus mycelium entrapped in calcium alginate gel  

Microsoft Academic Search

We studied the viability of fragmented mycelium of Pisolithus\\u000a tinctorius and Paxillus\\u000a involutus entrapped in calcium alginate gel to determine the efficacy of this method of producing ectomycorrhizal fungus inoculum.\\u000a Fungi were grown in MMN solution at 28??°C before being fragmented in a blender and subsequently entrapped in calcium alginate.\\u000a We tested different ratios of alginate and mycelium suspension to

Luciana da Silva Rodrigues; Maria Catarina Megumi Kasuya; Arnaldo Chaer Borges

1999-01-01

159

Fungus Threatens the Viability of Cotton For more than a century, the fungal disease cotton root  

E-print Network

Fungus Threatens the Viability of Cotton For more than a century, the fungal disease cotton root rot has been one of the most destructive cotton diseases in Texas. Cotton root rot reduces yield. With the disease essentially eliminating harvestable cotton on affected acres, economic losses from the disease

160

A New Methodology for Evaluation of Nematode Viability  

PubMed Central

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

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

2015-01-01

161

Sorting out bacterial viability with optical tweezers.  

PubMed

We have developed a method, using laser, optical tweezers and direct microscopic analysis of reproductive potential and membrane integrity, to assess single-cell viability in a stationary-phase Escherichia coli population. It is demonstrated here that a reduction in cell integrity, determined by using the fluorescent nucleic acid stain propidium iodide, correlated well with a reduction in cell proliferating potential during the stationary-phase period studied. Moreover, the same cells that exhibited reduced integrity were found to be the ones that failed to divide upon nutrient addition. A small but significant number of the intact cells (496 of 7,466 [6.6%]) failed to replicate. In other words, we did not find evidence for the existence of a large population of intact but nonculturable cells during the stationary-phase period studied but it is clear that reproductive ability can be lost prior to the loss of membrane integrity. In addition, about 1% of the stationary-phase cells were able to divide only once upon nutrient addition, and in a few cases, only one of the two cells produced by division was able to divide a second time, indicating that localized cell deterioration, inherited by only one of the daughters, may occur. The usefulness of the optical trapping methodology in elucidating the mechanisms involved in stationary-phase-induced bacterial death and population heterogeneity is discussed. PMID:10986260

Ericsson, M; Hanstorp, D; Hagberg, P; Enger, J; Nyström, T

2000-10-01

162

Viability of fresh mitral homograft valves  

PubMed Central

The present study was undertaken to measure and compare the viability of the mitral leaflet, chordae, and papillary muscle. The viability of the valves was assessed by autoradiography at regular intervals after sterilization and preservation in antibiotics and nutrient medium. The results showed different rates of decline in viability of the leaflet, muscle, and chordae of the mitral valves. Slightly more than 70% of the leaflet fibroblasts took up thymidine during the first 24 hours of storage. This is compared with 68% of papillary muscle fibroblasts and 40% of chordae fibroblasts. Viability of the chordae decreased rapidly and became pronounced at four weeks. One week is the maximum time for storage of mitral valves if it is desirable to preserve living cells in the chordae. PMID:4724496

Al-Janabi, Nawal; Ross, Donald N.

1973-01-01

163

Storage Viability and Optimization Web Service  

E-print Network

Electricity Load (kW): building electricity load profile Thethe modeled building site, including utility electricity andand Electricity Storage and Reliability on Microgrid Viability: A Study of Commercial Buildings

Stadler, Michael

2010-01-01

164

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

165

The effect of ultrasound-related stimuli on cell viability in microfluidic channels  

PubMed Central

Background In ultrasonic micro-devices, contrast agent micro-bubbles are known to initiate cavitation and streaming local to cells, potentially compromising cell viability. Here we investigate the effects of US alone by omitting contrast agent and monitoring cell viability under moderate-to-extreme ultrasound-related stimuli. Results Suspended H9c2 cardiac myoblasts were exposed to ultrasonic fields within a glass micro-capillary and their viability monitored under different US-related stimuli. An optimal injection flow rate of 2.6 mL/h was identified in which, high viability was maintained (~95%) and no mechanical stress towards cells was evident. This flow rate also allowed sufficient exposure of cells to US in order to induce bioeffects (~5 sec), whilst providing economical sample collection and processing times. Although the transducer temperature increased from ambient 23°C to 54°C at the maximum experimental voltage (29 Vpp), computational fluid dynamic simulations and controls (absence of US) revealed that the cell medium temperature did not exceed 34°C in the pressure nodal plane. Cells exposed to US amplitudes ranging from 0–29 Vpp, at a fixed frequency sweep period (tsw = 0.05 sec), revealed that viability was minimally affected up to ~15 Vpp. There was a ~17% reduction in viability at 21 Vpp, corresponding to the onset of Rayleigh-like streaming and a ~60% reduction at 29 Vpp, corresponding to increased streaming velocity or the potential onset of cavitation. At a fixed amplitude (29 Vpp) but with varying frequency sweep period (tsw = 0.02-0.50 sec), cell viability remained relatively constant at tsw ? 0.08 sec, whilst viability reduced at tsw < 0.08 sec and minimum viability recorded at tsw = 0.05 sec. Conclusion The absence of CA has enabled us to investigate the effect of US alone on cell viability. Moderate-to-extreme US-related stimuli of cells have allowed us to discriminate between stimuli that maintain high viability and stimuli that significantly reduce cell viability. Results from this study may be of potential interest to researchers in the field of US-induced intracellular drug delivery and ultrasonic manipulation of biological cells. PMID:23809777

2013-01-01

166

Economic Evaluation of Observatory Solar-Energy System  

NASA Technical Reports Server (NTRS)

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

1982-01-01

167

Modeling the determinants of industry political power: industry winners in the Economic Recovery Tax Act of 1981  

E-print Network

they benefit from the legislation. The Boolean analysis used in this study indicates that a distinct combination of both political action and economic factors present a clear pattern of causal conditions associated with both tax winners and losers. Using...

Kardell, Amy Louise

2004-09-30

168

34 CFR 403.114 - How does a State determine the number of economically disadvantaged students attending vocational...  

Code of Federal Regulations, 2010 CFR

34 Education 3 2010-07-01 2010-07-01 false ...economically disadvantaged students attending vocational education programs under the Secondary School Vocational Education Program? 403.114 Section 403.114...

2010-07-01

169

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

NASA Technical Reports Server (NTRS)

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

1973-01-01

170

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

NASA Astrophysics Data System (ADS)

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

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

2014-06-01

171

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

NASA Astrophysics Data System (ADS)

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

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

2014-02-01

172

Poxvirus Viability and Signatures in Historical Relics  

PubMed Central

Although it has been >30 years since the eradication of smallpox, the unearthing of well-preserved tissue material in which the virus may reside has called into question the viability of variola virus decades or centuries after its original occurrence. Experimental data to address the long-term stability and viability of the virus are limited. There are several instances of well-preserved corpses and tissues that have been examined for poxvirus viability and viral DNA. These historical specimens cause concern for potential exposures, and each situation should be approached cautiously and independently with the available information. Nevertheless, these specimens provide information on the history of a major disease and vaccination against it. PMID:24447382

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

2014-01-01

173

Poxvirus viability and signatures in historical relics.  

PubMed

Although it has been >30 years since the eradication of smallpox, the unearthing of well-preserved tissue material in which the virus may reside has called into question the viability of variola virus decades or centuries after its original occurrence. Experimental data to address the long-term stability and viability of the virus are limited. There are several instances of well-preserved corpses and tissues that have been examined for poxvirus viability and viral DNA. These historical specimens cause concern for potential exposures, and each situation should be approached cautiously and independently with the available information. Nevertheless, these specimens provide information on the history of a major disease and vaccination against it. PMID:24447382

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

2014-02-01

174

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

175

Determining and exploiting the distribution function of wind power forecasting error for the economic operation of autonomous power systems  

Microsoft Academic Search

Many efforts have been presented in the bibliography for wind power forecasting in power systems and few of them have been used for autonomous power systems. The impact of knowing the distribution function of wind power forecasting error in the economic operation of a power system is studied in this paper. The papers proposes that the distribution of the wind

Antonis G. Tsikalakis; Yiannis A. Katsigiannis; Pavlos S. Georgilakis; Nikos D. Hatziargyriou

2006-01-01

176

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

177

Viability of mesenchymal stem cells during electrospinning  

PubMed Central

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

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

2011-01-01

178

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

2013-04-01

179

Storage and Viability of Hedychium Pollen  

Technology Transfer Automated Retrieval System (TEKTRAN)

Hedychium species generally flower in the summer and fall, but some bloom in winter and spring times. The different flowering times of the species implies that there is a need to find a way for storing and conserving viable pollen. The maintenance of pollen viability depends on several factors, incl...

180

Political Economics: Explaining Economic Policy  

Microsoft Academic Search

What determines the size and form of redistributive programs, the extent and type of public goods provision, the burden of taxation across alternative tax bases, the size of government deficits, and the stance of monetary policy during the course of business and electoral cycles? A large and rapidly growing literature in political economics attempts to answer these questions. But so

Torsten Persson; Guido Tabellini

2000-01-01

181

Infrared Signatures to Discriminate Viability of Autoclaved Bacillus Spores  

SciTech Connect

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

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

2011-10-06

182

A cell viability assay based on monitoring respiration by optical oxygen sensing.  

PubMed

A cell viability assay based on monitoring of the metabolic activity of living cells via their consumption of dissolved oxygen has been developed. It uses a microwell plate format and disposable phosphorescent sensor inserts incorporated into each sample. The wells are subsequently sealed from ambient oxygen using a layer of mineral oil, and periodically scanned from underneath with a simple fiber-optic phosphorescent phase detector. Thus, dissolved oxygen levels and time profiles of cell respiration can be determined noninvasively and compared to each other. The system was tested by monitoring the viability of the fission yeast Schizosaccharomyces pombe. In comparison with the conventional cell densitometry assay, the optical oxygen sensor method could reliably monitor lower numbers of cells (10(4)-10(5) vs 10(6)-10(7) cells/ml for densitometry), and accurately determine culture viability within 1 h. The assay was then applied to determine the viability of samples treated with toxic agents such as azide and in response to expression of a physiological inducer of cell death, the Bcl-2 family member Bak. The results obtained confirm that measurement of cell respiration by this assay can serve as a predictable, reliable, and fast method for high-throughput determination of cell viability and growth. PMID:10660466

O'Riordan, T C; Buckley, D; Ogurtsov, V; O'Connor, R; Papkovsky, D B

2000-02-15

183

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...

184

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

ERIC Educational Resources Information Center

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

Vever, Daniel; And Others

1991-01-01

185

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

PubMed

In times of economic crisis, most countries face the dual challenge of fighting unemployment while restraining social expenditures and closing budget deficits. The spending cuts and lack of employment affect a large number of decisions that have a direct or indirect impact on health. This impact is likely to be unevenly distributed among different groups within the population, and therefore not only health levels may be at risk, but also their distribution. The main purpose of this paper is to explore links between unemployment, economic growth, inequality, and health. We regress a measure of health, the Health Human Development Index (HHDI), against a set of explanatory variables accounting for the countries' economic performance (GDP growth, unemployment, and income inequality), and some institutional factors related to welfare spending and the nature of the health systems for the past three decades. In addition, we explore the causes for different results obtained using an inequality-adjusted HHDI, vs. the unadjusted HHDI. We describe a panel data model, estimated by random effects, for 32 countries from 1980-2010, in five-year intervals. Our conclusion is that the high economic growth observed in the last decades, together with an increase in the levels of income inequality and/or poverty, explain the observed changes of our index, particularly when this indicator is weighted by health inequality. The remaining institutional variables (the share of social spending, health care expenditure, and the type of health systems) show the expected sign but are not statistically significant. A comment on the methodological pitfalls of the approach completes the analysis. PMID:24406664

López-Casasnovas, Guillem; Soley-Bori, Marina

2014-01-01

186

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

2014-05-01

187

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

PubMed

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

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

2015-02-01

188

Localization of determinants of fertility through measurement adaptations in developing-country settings: The case of Iran: Comment on "Analysis of economic determinants of fertility in Iran: a multilevel approach".  

PubMed

Studies investigating fertility decline in developing countries often adopt measures of determinants of fertility behavior developed based on observations from developed countries, without adapting them to the realities of the study setting. As a result, their findings are usually invalid, anomalous or statistically non-significant. This commentary draws on the research article by Moeeni and colleagues, as an exemplary work which has not adapted measures of two key economic determinants of fertility behavior, namely gender inequality and opportunity costs of childbearing, to the realities of Iran's economy. Measurement adaptations that can improve the study are discussed. PMID:25489600

Erfani, Amir

2014-12-01

189

[Perinatal care for children born on the threshold of viability--ethical and professional problems].  

PubMed

Determining the prognosis for survival of baby pregnancy with threatened preterm labor between 22 and 25 completed weeks of gestation remains problematic. The children born at the threshold of viability set a variety of complex medical, social and ethical decisions. They can be formolirani as follows: How small is small enough, or how to determine the limit of viability? What are the risks that these children? How to contact the parents of these children? What type of resuscitation is required in this group of children and how? PMID:23610917

Slancheva, B; Nikolov, A

2012-01-01

190

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

191

Maintaining dendritic cell viability in culture.  

PubMed

When mouse dendritic cells (DCs) are isolated from tissues, purified and placed in a nutritive culture they die more rapidly than would be expected from their normal turnover in vivo. This can distort culture assays of DC function. We therefore tested several approaches to prolonging DC survival in culture. Of several cytokines tested granulocyte-macrophage colony stimulating factor was most effective at preserving the viability of conventional DCs (cDCs) but was ineffective for plasmacytoid DCs (pDCs). Surprisingly, Fms-like tyrosine kinase 3 ligand, crucial for DC development, produced only a marginal improvement in DC survival in culture, and interleukin-3, reported to prevent apoptosis of human pDCs, produced only a minor improvement in survival of mouse DCs. Genetic manipulation of cell death pathways was also tested, to avoid activation effects exerted by cytokine signalling. The isolation of DCs from mice overexpressing Bcl-2 was especially effective in maintaining pDC viability but gave a lesser improvement in cDC viability. DCs isolated from Bim(-/-)Noxa(-/-) mice also showed improved culture survival, but in this case with pDCs showing the least improvement. PMID:25081090

Vremec, David; Hansen, Jacinta; Strasser, Andreas; Acha-Orbea, Hans; Zhan, Yifan; O'Keeffe, Meredith; Shortman, Ken

2015-02-01

192

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

193

Determination of the optimal and economical biofilter depth in an anaerobic hybrid reactor for treating livestock industrial wastewater.  

PubMed

A laboratory scale anaerobic hybrid reactor (AHR) being comprised of UASB and anaerobic biofilter was used to study the different biofilter depth with corresponding different critical HRT (1) and HRT (2) in treating livestock industrial wastewater, where the critical HRT (1) was defined as the HRT which resulted in the total COD in the effluent of the AHR exceeding in the influent at unsteady state, and the HRT (2) was defined as the HRT which resulted in the total COD in the effluent of the AHR exceeding the quality standard for discharging to sewer (in Hong Kong is Total COD < 1000 mg L1) at steady state. Two formulas expressing the relationship of different biofilter depth in the AHR and it's critical HRT (1) and HRT (2) in treating livestock industrial wastewater were obtained and used to design optimal and economical biofilter depth in a full scale AHR for treating livestock industrial wastewater on site. The performance of the full scale AHR indicated that using the experience formulas to design the optimal and economical biofilter depth in the full scale AHR for treating livestock industrial wastewater was successful. Experimental results also showed that the biofilter in the full scale AHR had not only physical filtration effect, but also had powerful biodegradation capability, furthermore, at unsteady state, the effect of biofilter on pollutant degrading in the full scale AHR was more great. PMID:15663312

Wang, L; Zhou, Q; Chua, H

2005-01-01

194

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

195

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

NASA Technical Reports Server (NTRS)

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.

1980-01-01

196

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

197

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

198

Kinetic viability assays using DRAQ7 probe.  

PubMed

Cell death within cell populations is a stochastic process where cell-to-cell variation in temporal progression through the various stages of cell death arises from asynchrony of subtle fluctuations in the signaling pathways. Most cell death assays rely on detection of the specific marker of cell demise at the end-point of cell culturing. Such an approach cannot account for the asynchrony and the stochastic nature of cell response to the death-inducing signal. There is a need therefore for rapid and high-throughput bioassays capable of continuously tracking viability of individual cells from the time of encountering a stress signal up to final stages of their demise. In this context, a new anthracycline derivative, DRAQ7, is gaining increasing interest as an easy-to-use marker capable of long-term monitoring of cell death in real-time. This novel probe neither penetrates the plasma membrane of living cells nor does it affect the cells' susceptibility to the death-inducing agents. However, when the membrane integrity is compromised, DRAQ7 enters cells undergoing demise and binds readily to nuclear DNA to report cell death. Here, we provide three sets of protocols for viability assays using DRAQ7 probe. The first protocol describes the innovative use of single-color DRAQ7 real-time assay to dynamically track cell viability. The second protocol outlines a simplified end-point DRAQ7 staining approach. The final protocol highlights the real-time and multiparametric apoptosis assay utilizing DRAQ7 dye concurrently with tetramethylrhodamine methyl ester (TMRM), the mitochondrial trans-membrane electrochemical potential (??m) sensing probe. PMID:23835805

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

2013-07-01

199

Kinetic viability assays using DRAQ7 probe  

PubMed Central

Cell death within cell populations is a stochastic process where cell-to-cell variation in temporal progression through the various stages of cell death arises from asynchrony of subtle fluctuations in the signaling pathways. Most cell death assays rely on detection of the specific marker of cell demise at the end-point of cell culturing. Such an approach cannot account for the asynchrony and the stochastic nature of cell response to the death-inducing signal There is a need therefore for rapid and high-throughput bioassays capable to continuously track viability of individual cells from the time of encountering a stress signal up to final stages of their demise. In this context, a new anthracycline derivative DRAQ7 is gaining increasing interest as an easy to use marker capable of long-term monitoring of cell death in real-time. This novel probe neither penetrates the plasma membrane of living cells nor does it affect cells susceptibility to the death inducing agents. However when the membrane integrity is compromised DRAQ7 enters cells undergoing demise and binds readily to nuclear DNA to report cell death. Here, we provide three sets of protocols for viability assays using DRAQ7 probe. The first protocol describes the innovative use of single color DRAQ7 real-time assay to dynamically track cell viability. The second protocol outlines a simplified end-point DRAQ7 staining approach. The final protocol highlights the real-time and multiparametric apoptosis assay utilizing DRAQ7 dye concurrently with tetramethylrhodamine methyl ester (TMRM), the mitochondrial trans-membrane electrochemical potential (??m) sensing probe. PMID:23835805

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

2013-01-01

200

Echinococcus metacestode: in search of viability markers.  

PubMed

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

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

2014-01-01

201

Echinococcus metacestode: in search of viability markers  

PubMed Central

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

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

2014-01-01

202

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

203

Use of Time-Aggregated Data in Economic Screening Analyses of Combined Heat and Power Systems  

SciTech Connect

Combined heat and power (CHP) projects (also known as cogeneration projects) usually undergo a series of assessments and viability checks before any commitment is made. A screening analysis, with electrical and thermal loads characterized on an annual basis, may be performed initially to quickly determine the economic viability of the proposed project. Screening analyses using time-aggregated data do not reflect several critical cost influences, however. Seasonal and diurnal variations in electrical and thermal loads, as well as time-of-use utility pricing structures, can have a dramatic impact on the economics. A more accurate economic assessment requires additional detailed data on electrical and thermal demand (e.g., hourly load data), which may not be readily available for the specific facility under study. Recent developments in CHP evaluation tools, however, can generate the needed hourly data through the use of historical data libraries and building simulation. This article utilizes model-generated hourly load data for four potential CHP applications and compares the calculated cost savings of a CHP system when evaluated on a time-aggregated (i.e., annual) basis to the savings when evaluated on an hour-by-hour basis. It is observed that the simple, aggregated analysis forecasts much greater savings (i.e., greater economic viability) than the more detailed hourly analysis. The findings confirm that the simpler tool produces results with a much more optimistic outlook, which, if taken by itself, might lead to erroneous project decisions. The more rigorous approach, being more reflective of actual requirements and conditions, presents a more accurate economic comparison of the alternatives, which, in turn, leads to better decision risk management.

Hudson II, Carl Randy [ORNL

2004-09-01

204

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

205

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

206

Morphological observation and analysis using automated image cytometry for the comparison of trypan blue and fluorescence-based viability detection method.  

PubMed

The ability to accurately determine cell viability is essential to performing a well-controlled biological experiment. Typical experiments range from standard cell culturing to advanced cell-based assays that may require cell viability measurement for downstream experiments. The traditional cell viability measurement method has been the trypan blue (TB) exclusion assay. However, since the introduction of fluorescence-based dyes for cell viability measurement using flow or image-based cytometry systems, there have been numerous publications comparing the two detection methods. Although previous studies have shown discrepancies between TB exclusion and fluorescence-based viability measurements, image-based morphological analysis was not performed in order to examine the viability discrepancies. In this work, we compared TB exclusion and fluorescence-based viability detection methods using image cytometry to observe morphological changes due to the effect of TB on dead cells. Imaging results showed that as the viability of a naturally-dying Jurkat cell sample decreased below 70 %, many TB-stained cells began to exhibit non-uniform morphological characteristics. Dead cells with these characteristics may be difficult to count under light microscopy, thus generating an artificially higher viability measurement compared to fluorescence-based method. These morphological observations can potentially explain the differences in viability measurement between the two methods. PMID:24643390

Chan, Leo Li-Ying; Kuksin, Dmitry; Laverty, Daniel J; Saldi, Stephanie; Qiu, Jean

2015-05-01

207

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

208

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

PubMed

The objective was to develop and validate a multilateral index to determine patient ability to pay for medication in low- and middle-income countries. Primary data were collected in 2009 from 117 cancer patients in China, India, Thailand, and Malaysia. The initial tool included income, expenditures, and assets-based items using ad hoc determined brackets. Principal components analysis was performed to determine final weights. Agreement (Kappa) was measured between results from the final tool and from an Impact Survey (IS) conducted after beginning drug therapy to quantify a patient's actual ability to pay in terms of number of drug cycles per year. The authors present the step-by-step methodology employed to develop the tool on a country-by-country basis. Overall Cronbach value was 0.84. Agreement between the Patient Financial Eligibility Tool (PFET) and IS was perfect (equal number of drug cycles) for 58.1% of patients, fair (1 cycle difference) for 29.1%, and poor (>1 cycle) for 12.8%. Overall Kappa was 0.76 (P<0.0001). The PFET is an effective tool for determining an individual's ability to pay for medication. Combined with tiered models for patient participation in the cost of medication, it could help to increase access to high-priced products in developing countries. PMID:23276290

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

2013-04-01

209

Health as an Informational Good: The Determinants of Child Nutrition and Mortality During Political and Economic Recovery in Uganda  

Microsoft Academic Search

Uganda suffers from a high rate of child mortality which has improved little if at all in the last twenty years. The paper uses data from the 1992 Integrated Household Survey to model the determinants of child mortality and malnutrition. Parental beliefs about health have a strong and very highly significant influence on child mortality. Education and income also play

John Mackinnon

210

Political, social and economic determinants of corporate social disclosure by multi-national firms in environmentally sensitive industries  

Microsoft Academic Search

Using examples from environmentally sensitive industries, the paper examines the determinants of corporate social disclosure (CSD). The paper moves beyond the traditional literature in two respects. First it is international in scope, examining the accounting disclosure responses of multi-national companies to the pressures implied by the nature and scope of their operations. Second, variables measuring political risk and social development

Steven Toms; J. Hasseldine; H. Massoud

2007-01-01

211

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

212

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

213

Viability of Sarcocystis neurona sporocysts and dose titration in gamma-interferon knockout mice  

Microsoft Academic Search

Gamma-interferon knockout mice have become the model animal used for studies on Sarcocystis neurona. In order to determine the viability of S. neurona sporocysts and to evaluate the course of the disease in these mice, sporocysts were collected from opossums (Didelphis virginiana), processed, and stored for varying periods of time. Gamma-interferon knockout mice were then inoculated orally with different isolates

M. A. Cheadle; S. M. Tanhauser; T. J. Scase; J. B. Dame; R. J. Mackay; P. E. Ginn; E. C. Greiner

2001-01-01

214

Egg viability in urinary schistosomiasis. II. Simplifying modifications and standardization of new methods.  

PubMed

Two new methods were recently introduced for the determination and quantification of egg viability in Schistosoma haematobium infections by staining eggs filtered from urine on Nytrel filters with mercurochrome and iodine. Both methods showed reasonable agreement with the best currently available method, centrifugation hatching, but it appeared that improved agreement could be obtained by modifications of timing and technique. The present paper describes the standardization of staining times and microscopic counting techniques; the modifications made gave substantially improved agreement with the reference method and achieved the most important objective, not to have zero estimates of viability when the centrifugation method detected hatching. PMID:7681485

Braun-Munzinger, R A; Southgate, B A

1993-04-01

215

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

NASA Astrophysics Data System (ADS)

Lasers have been shown to cause permanent shape change in cartilage via photothermally induced mechanical stress relaxation. While the biophysical properties of cartilage during laser irradiation have been studied, tissue viability following laser irradiation has not been fully characterized. In this study, cell viability staining and flow cytometry were used to determine chondrocyte viability following photothermal stress relaxation. Porcine septal cartilage slabs (10 X 25 X 1.5 mm) were irradiated with light from a Nd:YAG laser ((lambda) equals 1.32 micrometer, 25 W/cm2) while surface temperature, stress relaxation, and diffuse reflectance were recorded. Each slab received one, two, or three laser exposures (respective exposure times of 6.7, 7.2, 10 s), determined from measurements of diffuse reflectance, which correlate with mechanical stress relaxation. Irradiated samples were then divided into two groups analyzed immediately and at five days following laser exposure (the latter group was maintained in culture). Chondrocytes were isolated following serial enzymatic digestion with hyaluronidase, protease, and collagenase II for a total of 17 hours. Chondrocytes were then stained using SYTOR/DEAD RedTM (Molecular Probes; Eugene, OR) wherein live cells stained green (530 nm) and dead cells stained red (630 nm) when excited at 488 nm. A flow cytometer (FACScan, Becton Dickinson, Franklin Lakes, NJ) was then used to detect differential cell fluorescence; size; granularity; and the number of live cells, dead cells, and post irradiation debris in each treatment population. Nearly 60% of chondrocytes from reshaped cartilage samples isolated shortly after irradiation, were viable as determined using flow cytometry while non- irradiated controls were 100 percent viable. Specimens irradiated two or three times with the laser demonstrated increasing amounts of cellular debris along with a reduction in chondrocyte viability: 31 percent following two laser exposures, and 16 percent after three laser exposures. In those samples maintained in culture medium and assayed 5 days after irradiation, viability was reduced by 28 to 88 percent, with the least amount of deterioration in untreated and singly irradiated samples. Functional fluorescent dyes combined with flow cytometric analysis successfully determines the effect of laser irradiation on the viability of reshaped cartilage. The flow cytometric approach to viability is accurate, fast, and can handle large sample numbers and sizes. Most importantly, since the method reveals that a single laser exposure of 6.7 s (sufficient for sustained shape change) causes less than 40 percent acute reduction in viability, photothermal reshaping of cartilage may be further researched as a clinical alternative to conventional techniques.

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

2000-05-01

216

The influence of mechanical stimulation on osteocyte apoptosis and bone viability in human trabecular bone  

PubMed Central

It has been shown previously using in vivo and ex vivo animal models, that cyclical mechanical stimulation is capable of maintaining osteocyte viability through the control of apoptotic cell death. Here we have studied the effect of mechanical stimulation on osteocyte viability in human trabecular bone maintained in a 3-D bioreactor system. Bone samples, maintained in the bioreactor system for periods of 3, 7 and 27 days, were subjected to either cyclical mechanical stimulation which engendered a maximum of 3,000 ?strain in a waveform corresponding to physiological jumping exercise for 5 minutes daily or control unloading. Unloading resulted in a decrease in osteocyte viability within 3 days that was accompanied by increased levels of cellular apoptosis. Mechanical stimulation significantly reduced apoptosis (p?0.032) and improved the maintenance of osteocyte viability in bone from all patient samples. The percentage Alkaline Phosphatase (ALP) labelled bone surface was significantly increased (p?0.05) in response to mechanical stimulation in all samples as was the Bone Formation Rate (BFR/BS) (p=0.005) as determined by calcein label incorporation in the 27-day experiment. These data indicate that in this model system, mechanical stimulation is capable of maintaining osteocyte viability in human bone. PMID:17185839

Mann, V.; Huber, C.; Kogianni, G.; Jones, D.; Noble, B.

2007-01-01

217

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

218

Managing economic and virtual economic capital within financial conglomerates  

Microsoft Academic Search

In the present contribution we show how the optimal amount of economic capital can be derived such that it minimizes the economic cost of risk-bearing. The economic cost of risk-bearing takes into account the cost of the economic capital as well as the cost of the residual risk. In addition to the absolute problem of the determination of the amount

Marc J. Goovaerts; orre E Vanden; Roger J. A. Laeven

2003-01-01

219

Preparation and storage of platelet concentrates. II. Storage variables influencing platelet viability and function.  

PubMed

Factors affecting the viability and function of stored platelet concentrates have been investigated in a blood component programme. It was found that platelets could be maintained for up to 72 h without bacterial contamination under the following conditions: (1) surgical skin preparation at venipuncture site; (2) blood collection in CPD or ACD anticoagulant in a closed bag system; (3) centrifugation of PRP at 3000 g for 20 min; (4) storage in Fenwal PL-146, Cutter CL-2383, or McGaw plastic bags; (5) resuspension of the platelet pellet in 70 ml residual plasma; (6) storage at 22+/-2 degrees C; and (7) constant gentle mixing throughout storage. Platelet viability as determined by recovery and survival is largely maintained, as is platelet function measured by template bleeding time. Both viability and function of concentrated platelets stored at 4 degrees C are severely compromised. PMID:10956

Slichter, S J; Harker, L A

1976-11-01

220

Determinants of road traffic injuries in drivers in a rapid highly economically developing country: a major global public health crisis  

Microsoft Academic Search

AimThe objective of this study was to determine the characteristics of road traffic injuries (RTIs) among Qatari drivers and examine the human behavioural and environmental risk factors associated in occurrence of RTIs.DesignThis is a cross sectional survey.SettingPrimary Healthcare Centers in the State of Qatar.MethodsThis study was conducted during the period of February–July 2009. A random sample of 1800 Qatari drivers

A Bener; H R Burgut; H Sidahmed; R AlBuz; R Sanya; W Ali Khan

2010-01-01

221

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

PubMed Central

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

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

2013-01-01

222

Recent trends in automobile recycling: An energy and economic assessment  

SciTech Connect

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

Curlee, T.R.; Das, S.; Rizy, C.G. [Oak Ridge National Lab., TN (United States); Schexanyder, S.M. [Tennessee Univ., Knoxville, TN (United States). Dept. of Biochemistry

1994-03-01

223

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

224

Determination of natural and socio-economic factors affecting landslide damage: an econometric approach using empirical evidence from the Calabria Region (Southern Italy)  

NASA Astrophysics Data System (ADS)

Many studies investigated how natural and human factors control the occurrence of landslides. In addition, considerable efforts have been made to quantitatively and qualitatively estimate damage, direct as well as indirect, due to the occurrence of landslides. However, only very few studies explicitly investigate how socio-economic factors affect the magnitude of damage caused by a landslide event. Nevertheless, socio-economic factors will be crucial determinants of landslide damage. For example, at household level, more wealthy households will be able to build houses in areas less susceptible to landslides or will be more able to take preventive measures to mitigate landslide damage. At the same time, the higher the income the higher the value of the property that will be damaged in case of a landslide occurrence. At regional level, the landslide damage is likely to depend on factors such as population density, income level and distribution, and rurality. In addition, it should be taken into account that historical data or inventories will be more precise when it comes to reporting landslide frequency and damage in the more recent years, while events that occurred longer ago are less likely to be reported unless major damage was caused. This might give the false impression that landslides occurred less frequently but were more damaging in the past. Therefore, this study econometrically estimates a landslide damage function. Based on a landslide inventory for an Italian region, landslide damage index is calculated for landslide damage assessment. Using state of the art econometric techniques, we identify which natural and socio-economic factors significantly affect landslide damage while correcting for time fixed effects. As such it provides a useful tool to predict future land damage. Furthermore, it provides useful insights for policy makers about the factors they should primarily try to alter in order to reduce landslide damage.

Petrucci, O.; Vranken, L.

2012-04-01

225

Economic perspectives of using indicators  

Microsoft Academic Search

This article deals with the interrelation of ecological and economic aspects through the use of indicators. Two aspects are painted out: the first being the measurement of the economic value of ecological services, and the second being the integration of economic aspects into comprehensive indicator systems.The measurement of the economic value provides a means of determining consumer-orientated values of landscapes

Elisabeth Osinski; Jochen Kantelhardt; Alois Heissenhuber

2003-01-01

226

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

PubMed Central

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

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

2014-01-01

227

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

228

Extending the viability of acute brain slices  

PubMed Central

The lifespan of an acute brain slice is approximately 6–12?hours, limiting potential experimentation time. We have designed a new recovery incubation system capable of extending their lifespan to more than 36?hours. This system controls the temperature of the incubated artificial cerebral spinal fluid (aCSF) while continuously passing the fluid through a UVC filtration system and simultaneously monitoring temperature and pH. The combination of controlled temperature and UVC filtering maintains bacteria levels in the lag phase and leads to the dramatic extension of the brain slice lifespan. Brain slice viability was validated through electrophysiological recordings as well as live/dead cell assays. This system benefits researchers by monitoring incubation conditions and standardizing this artificial environment. It further provides viable tissue for two experimental days, reducing the time spent preparing brain slices and the number of animals required for research. PMID:24930889

Buskila, Yossi; Breen, Paul P.; Tapson, Jonathan; van Schaik, André; Barton, Matthew; Morley, John W.

2014-01-01

229

Artificial evolution by viability rather than competition.  

PubMed

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

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

2014-01-01

230

Measurements of tissue viability in transplantation.  

PubMed Central

Near-infrared spectroscopy has primarily been used in monitoring changes in cerebral haemoglobin oxygenation and haemodynamics. However its use as a method for the assessment of tissue viability following transplantation has recently been explored experimentally in our laboratory. The ability to measure changes in oxygenation and perfusion during harvesting and following transplantation of organs or transfer of free and pedicled flaps potentially important in reconstructive surgery. We have found that near-infrared spectroscopy is extremely useful in detecting vaso-occlusive events and can accurately and reliably distinguish between arterial, venous or total occlusions. Venous congestion indicated by raised levels of deoxygenated haemoglobin with a concomitant increase in blood volume and the presence and magnitude of reactive hyperaemia are both easily recognizable features by near-infrared spectroscopy. We have shown that near-infrared spectroscopy measurements of venous congestion in kidneys (and other tissues) following prolonged storage correlate with medullary vascular congestion confirmed by angiographical and histological analysis of intrarenal perfusion. Clinically we have shown that flap perfusion can be improved by altering fluid replacement regimes and the addition of ionotropes. Cerebral near-infrared spectroscopy measurements in a liver transplant model showed statistically significant differences within minutes after the anhepatic phase in cerebral perfusion and oxygenation, between animals transplanted with ischaemically damaged livers compared to those isografted with minimally stored livers. Similarly we have found that near-infrared spectroscopy can be used as a monitor to assess the adequacy of fluid or blood replacement in haemorrhagic and hypovolaemic models. We believe that near-infrared spectroscopy provides a sensitive and reliable postoperative method for the assessment of tissue viability following the transfer of free and pedicled flaps and organs. PMID:9232856

Thorniley, M S; Simpkin, S; Balogun, E; Khaw, K; Shurey, C; Burton, K; Green, C J

1997-01-01

231

Artificial Evolution by Viability Rather than Competition  

PubMed Central

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

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

2014-01-01

232

Viability and Isolation of Marine Bacteria by Dilution Culture: Theory, Procedures, and Initial Results  

PubMed Central

Dilution culture, a method for growing the typical small bacteria from natural aquatic assemblages, has been developed. Each of 11 experimental trials of the technique was successful. Populations are measured, diluted to a small and known number of cells, inoculated into unamended sterilized seawater, and examined three times for the presence of 104 or more cells per ml over a 9-week interval. Mean viability for assemblage members is obtained from the frequency of growth, and many of the cultures produced are pure. Statistical formulations for determining viability and the frequency of pure culture production are derived. Formulations for associated errors are derived as well. Computer simulations of experiments agreed with computed values within the expected error, which verified the formulations. These led to strategies for optimizing viability determinations and pure culture production. Viabilities were usually between 2 and 60% and decreased with >5 mg of amino acids per liter as carbon. In view of difficulties in growing marine oligobacteria, these high values are noteworthy. Significant differences in population characteristics during growth, observed by high-resolution flow cytometry, suggested substantial population diversity. Growth of total populations as well as of cytometry-resolved subpopulations sometimes were truncated at levels of near 104 cells per ml, showing that viable cells could escape detection. Viability is therefore defined as the ability to grow to that population; true viabilities could be even higher. Doubling times, based on whole populations as well as individual subpopulations, were in the 1-day to 1-week range. Data were examined for changes in viability with dilution suggesting cell-cell interactions, but none could be confirmed. The frequency of pure culture production can be adjusted by inoculum size if the viability is known. These apparently pure cultures produced retained the size and apparent DNA-content characteristic of the bulk of the organisms in the parent seawater. Three cultures are now available, two of which have been carried for 3 years. The method is thus seen as a useful step for improving our understanding of typical aquatic organisms. PMID:16348896

Button, D. K.; Schut, Frits; Quang, Pham; Martin, Ravonna; Robertson, Betsy R.

1993-01-01

233

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

PubMed

Health Impact Assessment (HIA) is a practice that has grown in popularity worldwide, since the end of the 1990s. Originally used in the framework of Environmental Impact Assessments (EIAs), HIA has become enriched through the addition of knowledge and principles based on the social determinants of health and the tackling of health inequalities, and has been brought to bear on the policy-planning process at all levels of government. HIA has three overlapping objectives: to assess the potential effects of a policy on health, to encourage citizen and stakeholder participation in the impact analysis process, and to inform the decision-making process. This article briefly defines HIA; defines its standardized process in successive steps, which allows users to give structure to their actions and to establish the steps to be followed (detection, framing, analysis, recommendations and evaluation); and offers three examples of HIA in three different situations: the Geneva canton of Switzerland; Rennes, France; and in the Montérégie region of Quebec, Canada. Together, these illustrations show that HIA is a promising strategy to influence local decisions and to integrate health into projects and policies at the local and regional levels. PMID:24737808

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

2014-03-01

234

Flow cytometric viability assessment of lactic acid bacteria starter cultures produced by fluidized bed drying.  

PubMed

For starter culture production, fluidized bed drying is an efficient and cost-effective alternative to the most frequently used freeze drying method. However, fluidized bed drying also poses damaging or lethal stress to bacteria. Therefore, investigation of impact of process variables and conditions on viability of starter cultures produced by fluidized bed drying is of major interest. Viability of bacteria is most frequently assessed by plate counting. While reproductive growth of cells can be characterized by the number of colony-forming units, it cannot provide the number of viable-but-nonculturable cells. However, in starter cultures, these cells still contribute to the fermentation during food production. In this study, flow cytometry was applied to assess viability of Lactobacillus plantarum starter cultures by membrane integrity analysis using SYBR®Green I and propidium iodide staining. The enumeration method established allowed for rapid, precise and sensitive determination of viable cell concentration, and was used to investigate effects of fluidized bed drying and storage on viability of L. plantarum. Drying caused substantial membrane damage on cells, most likely due to dehydration and oxidative stress. Nevertheless, high bacterial survival rates were obtained, and granulates contained in the average 2.7?×?10(9) viable cells/g. Furthermore, increased temperatures reduced viability of bacteria during storage. Differences in results of flow cytometry and plate counting suggested an occurrence of viable-but-nonculturable cells during storage. Overall, flow cytometric viability assessment is highly feasible for rapid routine in-process control in production of L. plantarum starter cultures, produced by fluidized bed drying. PMID:24584512

Bensch, Gerald; Rüger, Marc; Wassermann, Magdalena; Weinholz, Susann; Reichl, Udo; Cordes, Christiana

2014-06-01

235

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

PubMed

Little is known regarding the range of conditions in which many Perkinsus species may proliferate, making it difficult to predict conditions favorable for their expansion, to identify conditions inducing mortality, or to identify instances of potential cross-infectivity among sympatric host species. In this study, the effects of salinity on viability, metabolic activity and proliferation of P. marinus, P. olseni and P. chesapeaki were determined. Specifically, this research examined the effects of 5 salinities (7, 11, 15, 25, 35 per thousand), (1) without acclimation, on the viability and metabolic activity of 2 isolates of each Perkinsus species, and (2) with acclimation, on the viability, metabolic activity, size and number of 1 isolate of each species. P. chesapeaki showed the widest range of salinity tolerance of the 3 species, with high viability and cell proliferation at all salinities tested. Although P. chesapeaki originated from low salinity areas (i.e. <15 per thousand), several measures (i.e. cell number and metabolic activity) indicated that higher salinities (15, 25 per thousand) were more favorable for its growth. P. olseni, originating from high salinity areas, had better viability and proliferation at the higher salinities (15, 25, 35 per thousand). Distinct differences in acute salinity response of the 2 P. olseni isolates at lower salinities (7, 11 per thousand), however, suggest the need for a more expansive comparison of isolates to better define the lower salinity tolerance. Lastly, P. marinus was more tolerant of the lower salinities (7 and 11 per thousand) than P. olseni, but exhibited reduced viability at 7 per thousand, even after acclimation. PMID:16922001

La Peyre, Megan; Casas, Sandra; La Peyre, Jerome

2006-07-11

236

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

PubMed Central

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

Sulusoglu, Melekber; Cavusoglu, Aysun

2014-01-01

237

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

2006-10-01

238

ECONOMIC AND FINANCIAL ANALYSIS OF PEANUT PRODUCTION IN BULGARIA ????????? ???????????? ?????? ?? ?????????????? ?? ??????? ? ????????  

Microsoft Academic Search

Peanut is not listed as one of the major crops in the Bulgarian agricultural sector, but its economic and fi nancial viability is promising, but unknown. We use enterprise budgets, capital budgeting techniques, risk analysis and logistic regression models to examine the fi nancial and economic structure of peanut farms and to evaluate the factors infl uencing short and long-term

Nelly Bencheva; Carel Ligeon; Stanko Delikostadinov; Naveen Puppala; Curtis Jolly

239

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

240

Determinants  

NSDL National Science Digital Library

Created by Lewis Blake and Stephanie Fitchett of the Connected Curriculum Project, the purposes of this module are to explore the properties of determinants of matrices and to develop an important theoretical formula. This is part of a larger collection of material hosted by Duke University.

Blake, Lewis

241

The viability of photovoltaics on the Martian surface  

NASA Technical Reports Server (NTRS)

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

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

1994-01-01

242

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

243

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

244

Relationship between desiccation and viability of maize pollen  

Microsoft Academic Search

Controlling pollination is necessary to ensure maximum kernel set and high levels of genetic purity in maize. Current approaches for measuring maize pollen production are fairly simple and accurate, but they do not evaluate pollen viability. A simple and reliable technique to assess loss of pollen viability during its transport in air is required to simulate the pollination process and

Agustin E. Fonseca; Mark E. Westgate

2005-01-01

245

INNOVATION IN HOME ECONOMICS.  

ERIC Educational Resources Information Center

THIS GUIDE IS FOR TEACHER USE IN PLANNING A SHORT COURSE IN HOME ECONOMICS PROGRAM FOR 11TH AND 12TH GRADE BOYS AND GIRLS. IT WAS DEVELOPED BY ARLINGTON COUNTY SCHOOLS, VIRGINIA, AND THE CONTENT WAS DETERMINED BY A COMMITTEE OF HOME ECONOMICS TEACHERS, A PRINCIPAL, AND A FEW SELECTED STUDENTS. THE OBJECTIVE OF THE COURSE IS TO PROVIDE A SERIES OF…

Department of Home Economics, Washington, DC.

246

Economics of Cancer  

Cancer.gov

The Applied Research Program supports several activities relevant to the economics of cancer. These include developing data resources and methods to produce estimates of the economic burden of cancer, developing detailed estimates of and determinants of the cost of cancer prevention, screening, treatment and follow-up services, and estimating the costs of cancer treatment for patients in clinical trials.

247

Economics Department Mission Statement  

E-print Network

decisions rigorously. 4. economic efficiency, and how the market system achieves it and whether and how and benefits. 5. long-run economic growth and its determinants, and the role of the market and public policies of financial markets in both long-run growth and short-term fluctuations. 8. the growing importance

Jiang, Huiqiang

248

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

PubMed Central

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

2013-01-01

249

Bioactive TTR105-115-based amyloid fibrils reduce the viability of mammalian cells.  

PubMed

A growing number of protein-based fibrous biomaterials have been produced with a cross-? amyloid core yet the long-term effect of these materials on cell viability and the influence of core and non-core protein sequences on viability is not well understood. Here, synthetic bioactive TTR1-RGD and control TTR1-RAD or TTR1 fibrils were used to test the response of mammalian cells. At high fibril concentrations cell viability was reduced, as assessed by mitochondrial reduction assays, lactate dehydrogenase membrane integrity assays and apoptotic biomarkers. This reduction occurred despite the high density of RGD cell adhesion ligands and use of cells displaying integrin receptors. Cell viability was affected by fibril size, maturity and whether fibrils were added to the cell media or as a pre-coated surface layer. These findings show that while cells initially interact well with synthetic fibrils, cellular integrity can be compromised over longer periods of time, suggesting a better understanding of the role of core and non-core residues in determining cellular interactions is required before TTR1-based fibrils are used as biomaterials. PMID:25678120

Bongiovanni, Marie N; Gras, Sally L

2015-04-01

250

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

2010-07-01

251

Viability, Apoptosis, Proliferation, Activation, and Cytokine Secretion of Human Keratoconus Keratocytes after Cross-Linking  

PubMed Central

Purpose. The purpose of this study was to determine the impact of cross-linking (CXL) on viability, apoptosis, proliferation, activation, and cytokine secretion of human keratoconus (KC) keratocytes, in vitro. Methods. Primary KC keratocytes were cultured in DMEM/Ham's F12 medium supplemented with 10% FCS and underwent UVA illumination (370?nm, 2?J/cm2) during exposure to 0.1% riboflavin and 20% Dextran in PBS. Twenty-four hours after CXL, viability was assessed using Alamar blue assay; apoptosis using APO-DIRECT Kit; proliferation using ELISA-BrdU kit; and CD34 and alpha-smooth muscle actin (?-SMA) expression using flow cytometry. Five and 24 hours after CXL, FGFb, HGF, TGF?1, VEGF, KGF, IL-1?, IL-6, and IL-8 secretion was measured using enzyme-linked-immunoabsorbent assay (ELISA). Results. Following CXL, cell viability and proliferation decreased (P < 0.05; P = 0.009), the percentage of apoptotic keratocytes increased (P < 0.05) significantly, and CD34 and ?-SMA expression remained unchanged (P > 0.06). Five hours after CXL, FGFb secretion increased significantly (P = 0.037); however no other cytokine secretion differed significantly from controls after 5 or 24 hours (P > 0.12). Conclusions. Cross-linking decreases viability, triggers apoptosis, and inhibits proliferation, without an impact on multipotent hematopoietic stem cell transformation and myofibroblastic transformation of KC keratocytes. CXL triggers FGFb secretion of KC keratocytes transiently (5 hours), normalizing after 24 hours. PMID:25699261

Stachon, Tanja; Wang, Jiong; Seitz, Berthold; Szentmáry, Nóra

2015-01-01

252

Texas plant demonstrates viability of coal option  

Microsoft Academic Search

This article examines the design and economics of a recently operational coal-fired plant that uses proven technology and careful engineering to provide efficient and cost-effective power production and emissions control. The topics of the article include new design features, unit startup, SO[sub 2] removal, cooling requirements, distributed control system, key plant equipment, boiler and auxiliaries, emissions control systems, absorber vessels,

R. R. Bryan; A. A. Smith; C. Farmer

1993-01-01

253

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

254

Medicine prices in urban Mozambique: a public health and economic study of pharmaceutical markets and price determinants in low-income settings.  

PubMed

It has been suggested that medicines are unaffordable in low-income countries and that world manufacturing and trade policies are responsible for high prices. This research investigates medicine prices in urban Mozambique with the objective of understanding how prices are formed and with what public health implications. The study adopts an economic framework and uses a combination of quantitative and qualitative methods to analyse local pharmaceutical prices and markets. The research findings suggest that: (a) local mark-ups are responsible for up to two-thirds of drugs' final prices in private pharmacies; (b) statutory profit and cost ceilings are applied unevenly, due to lack of government control and collusion among suppliers; and (c) the local market appears to respond effectively to the urban population's diverse needs through its low-cost and high-cost segments, although uncertainty around the quality of generics may be inducing consumers to purchase less affordable drugs. We conclude that local markets play a larger than expected role in the determination of prices in Mozambique, and that more research is needed to address the complex issue of affordability of medicines in low-income countries. We also argue that price controls may not be the most effective way to influence access to medicines in low-income countries, and managing demand and supply towards cheaper effective drugs appears a more suitable policy option. PMID:19843636

Russo, Giuliano; McPake, Barbara

2010-01-01

255

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

NASA Technical Reports Server (NTRS)

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

1982-01-01

256

Strengths and Weaknesses of a Population Viability Analysis for Philippine Tarsiers ( Tarsius syrichta )  

Microsoft Academic Search

Population viability analysis (PVA) has been increasingly used to guide conservation planning for many primate species. I\\u000a present an assessment of a PVA for Philippine tarsiers (Tarsius syrichta) in Corella, Bohol. The objectives were to determine 1) area requirements and 2) spatial configurations of habitat patches\\u000a necessary for viable populations in Corella. I used available life history parameters and ecological

Irene Neri-Arboleda

2010-01-01

257

Population Viability Analysis of the Florida Manatee ( Trichechus manatus latirostris ), 1976-1991  

Microsoft Academic Search

Recent development of age-determination techniques for Florida manatees ( Trichechus manatus lati- rostris ) has permitted derivation of age-specific data on reproduction and survival of a sample of 1212 car- casses obtained throughout Florida from 1976-1991. Population viability analysis using these data projects a slightly negative growth rate ( 2 0.003) and an unacceptably low probability of persistence (0.44) over

MIRIAM MARMONTEL; STEPHEN R. HUMPHREY; THOMAS J. O'SHEA

258

Effects of neutrophil-derived oxidants on intestinal permeability, electrolyte transport, and epithelial cell viability  

Microsoft Academic Search

There are several pathophysiologic conditions in which intestinal inflammation is associated with enhanced mucosal permeability, fluid loss, and epithelial cell injury. The objective of this study was to determine the effects of polymorphonuclear leukocyte (PMN) -derived oxidants on ileal mucosal permeability in vivo as well as electrolyte transport and epithelial cell viability in vitro. Using blood-tolumen clearance of [51Cr]EDTA as

Matthew B. Grisham; Timothy S. Gaginella; Christoph Ritter; Hiroshi Tamai; Robert M. Be; D. Neil Granger

1990-01-01

259

Impact of Air Transportation on Regional Economic and Social Connectivity in the United States  

E-print Network

This paper identifies some of the forces that influence the impact of air transportation on regional connectivity and economic productivity in the United States. In light of recent threats to the financial viability of the ...

Tam, Ryan

260

75 FR 74077 - Information Collection for Native American Business Development Institute Funding for Economic...  

Federal Register 2010, 2011, 2012, 2013, 2014

...American Indian tribes and tribal businesses to make informed decisions regarding...viability of an economic development project or business or the practicality of a technology...for research and development projects, requests for funding of...

2010-11-30

261

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

PubMed Central

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.

2013-01-01

262

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.

263

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

2010-05-11

264

Decreased winter severity increases viability of a montane frog population  

PubMed Central

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.

2010-01-01

265

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?˛ and about 300 J cm?˛ 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?˛ and less than 1 J cm?˛ 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

2012-03-01

266

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

2012-06-01

267

CT imaging of myocardial viability: experimental and clinical evidence  

PubMed Central

Summary Summary Over the last decade, imaging of myocardial viability has become a well-established indication in patients suffering from myocardial infarction. Myocardial viability imaging is routinely performed using 18F-fluorodeoxyglucose positron emission tomography, single-photon emission computed tomography or magnetic resonance imaging. Only recently have several multi-slice spiral computed tomography (MSCT) techniques been evaluated for visualisation of myocardial infarction. This review describes the different concepts of MSCT viability imaging. MSCT assessment of myocardial morphology, myocardial perfusion imaging and delayed myocardial contrast enhancement are introduced, with the latter evolving as the key concept of MSCT viability imaging. Clinical relevance of the different MSCT techniques is described. PMID:17612749

Mahnken, Andreas H; Mühlenbruch, Georg; Günther, Rolf W.; Wildberger, Joachim E.

2007-01-01

268

Plant Population Viability and Restoration Potential for Rare Plants  

E-print Network

Plant Population Viability and Restoration Potential for Rare Plants Near Solar Installations solar developments in the Mojave and Sonoran deserts of California will significantly impact plants of current plant populations, assess their habitat requirements, and provide information on the feasibility

269

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

270

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

SciTech Connect

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.

Not Available

1980-09-01

271

Viability of freeze dried microencapsulated human retinal pigment epithelial cells.  

PubMed

Encapsulated human retinal pigment epithelial cell line ARPE-19 has been successfully used in experimental cell therapy of retinal degenerations and Parkinson's disease, but the long-term storage of encapsulated cells is still an unresolved question. Reconstitution of viable encapsulated cells from dry form would benefit the development of cell therapy products. We freeze dried and reconstituted microencapsulated ARPE19 and ARPE19-SEAP cells. Cross-linked alginate matrix with polycation (poly-l-lysine, cationic starch) coating was used for microencapsulation. Cell viability was assessed with fluorescence microscopy and oxygen consumption of the cells. Freeze dried and reconstituted cell microcapsules were imaged using scanning electron microscopy (SEM) and environmental scanning electron microscopy (ESEM). We show partial viability of microencapsulated cells after freeze-drying. Unlike poly-l-lysine (PLL) coating, cationic starch supported microcapsule shape and cell viability during freeze-drying. Trehalose pre-treatment augmented cell viability. Likewise, some lyoprotectants (trehalose, glycerol) enabled preservation of cell viability. Upon reconstitution the freeze dried cell microcapsules rapidly regained their original spherical shape. This proof-of-concept study demonstrates that microencapsulated cells can retain their viability during freeze-drying. Therefore, this approach can be further optimized for the benefit of cell therapy product development. PMID:22820032

Wikström, Jonna; Elomaa, Matti; Nevala, Laura; Räikkönen, Johanna; Heljo, Petteri; Urtti, Arto; Yliperttula, Marjo

2012-09-29

272

Economics & BusinEss Economics  

E-print Network

to develop an interest in fields such as government policy, developing countries and international trade choose from a wide range of other courses, studying topics such as environmental economics, government debt and the macroeconomy, economics of health,economicsofinequalityandpoverty, and economics of team

Guo, Zaoyang

273

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. PMID:21666808

Urbanavi?ius, Linas; Pattyn, Piet; Van de Putte, Dirk; Venskutonis, Donatas

2011-01-01

274

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. PMID:20435763

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

2010-01-01

275

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. PMID:17595938

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

2007-01-01

276

The influence of pleiotropy between viability and pollen fates on mating system evolution.  

PubMed

Floral displays are functionally and genetically integrated structures, so modifications to display will likely affect multiple fitness components (pleiotropy), including pollen export and self-pollination, and therefore selfing rate. Consequently, the great diversities of floral displays and of mating systems found among angiosperms have likely co-evolved. I extend previous models of mating system evolution to determine how pleiotropy that links viability (e.g., probability of survival to reproduction) and the allocation of pollen for export and selfing affects the evolution of selfing, outcrossing, and in particular, mixed mating. I show that the outcome depends on how pollen shifts from being exported, unused, or used for selfing. Furthermore, pleiotropy that affects viability can explain observations not addressed by previous theory, including the evolution of mixed mating despite high inbreeding depression in the absence of pollen-limitation. Therefore, pleiotropy may play a key role in explaining selfing rates for such species that exhibit otherwise enigmatic mating systems. PMID:25448089

Jordan, Crispin Y

2015-02-01

277

Polyphenolic extracts of edible flowers incorporated onto atelocollagen matrices and their effect on cell viability.  

PubMed

The phenolic extract of chives flowers (Allium schoenoprasum, Liliaceae), introduced Sage (Salvia pratensis, Lamiaceae), European elderberry (Sambucus nigra, Caprifoliaceae) and common dandelion (Taraxacum officinale, Asteraceae) were characterised by High Performance Liquid Chromatography and incorporated in different concentrations onto atelocollagen thin films. In order to assess the biological impact of these phenolic compounds on cell viability, human immortalised non-tumorigenic keratinocyte cell line was seeded on the thin films and cell proliferation was determined by using an MTT assay. In addition, their antimicrobial activity was estimated by using an agar diffusion test. Data indicated the concomitance between cell viability and concentration of polyphenols. These findings suggest that these phenolic-endowed atelocollagen films might be suitable for tissue engineering applications, on account of the combined activity of polyphenols and collagen. PMID:24177700

López-García, Jorge; Kuceková, Zdenka; Humpolí?ek, Petr; Ml?ek, Ji?i; Sáha, Petr

2013-01-01

278

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

USGS Publications Warehouse

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

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

2009-01-01

279

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

PubMed Central

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

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

2014-01-01

280

Longitudinal Studies ofGiardiaContamination in Two Community Drinking Water Supplies: Cyst Levels, Parasite Viability, and Health Impact  

Microsoft Academic Search

Giardiacyst concentrations were determined in an inventory of 153 raw and 91 chlorinated drinking water samples collected at 86 sites from throughout the western Canadian province of British Columbia. Sixty-four percent of raw water samples were cyst positive (69% of sites). Cyst concentrations were lower in chlorinated than in raw water. The viability of cysts in drinking water samples assessed

JUDITH ISAAC-RENTON; WILLIAM MOOREHEAD; ANDANDREW ROSS

1996-01-01

281

Latent period and viability of Puccinia jaceae var. solstitialis urediniospores: Implications for biological control of yellow starthistle  

Microsoft Academic Search

Since the introduction of Puccinia jaceae var. solstitialis into California in 2003, multiple urediniospore generations have been observed, along with teliospores and pycnia, on yellow starthistle (Centaurea solstitialis). A field and laboratory study of urediniospore viability was conducted to determine the potential of using infected plant material for redistribution of inoculum into new areas. To better understand the life history

Alison J. Fisher; Dale M. Woods; Lincoln Smith; William L. Bruckart

2008-01-01

282

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

283

Application of wide-field optical coherence tomography to monitoring of viability of rat brain in vivo  

NASA Astrophysics Data System (ADS)

We investigated the feasibility of OCT in monitoring the viability of the brain. It was confirmed that after an overdose of pentobarbital sodium salt for an euthanasia, the OCT signal intensity increased before cardiac arrest and finally became 2.7 times, and by periodically changing the tissue temperature from 20 to 32 °C in vivo, average correlation coefficients between the ratio of signal intensity (RSI) and temperature were determined to be -0:42 to -0:50. RSI reversibly changed with subsequent variations of temperatures and finally increased rapidly just before cardiac arrest. These results indicate that RSI could correspond to decreases in viability.

Sato, Manabu; Nishidate, Izumi

2014-05-01

284

Economics Challenge  

NSDL National Science Digital Library

The Economics Challenge is a economics competition for high school students living in the twelfth district -- Alaska, Arizona, California, Hawaii, Idaho, Oregon, Utah, and Washington. The competition strives to "increase [high school students's] knowledge and understanding of economics." Winning team members will receive $1,000 US savings bonds. The site includes a description of the competition, registration forms for these states, and two sets of practice questions and answers.

285

Differential effects of fucoidans with low and high molecular weight on the viability and function of spleen cells.  

PubMed

Fucoidan is an edible sulfated polysaccharide purified from brown algae that has multiple biological activities. However, the effects of fucoidans of different molecular weights on immune cells have not been determined. Thus, we treated spleen cells with low- and high-molecular-weight fucoidans (LMF and HMF, respectively). Viability assays demonstrated that HMF enhanced the viability and prevented the death of spleen cells. Furthermore, functional analysis revealed that HMF significantly increased the production of interferon-? and nitric oxide. In contrast, LMF had low activity and was relatively toxic to spleen cells. Taken together, these results indicate that HMF makes the greatest contribution to the immunostimulatory activity of fucoidan mixtures. Additionally, fucoidans with different molecular weights may have different effects on the viability and function of immune cells. This study increases our understanding of fucoidans, and may broaden their use in the basic research and clinical fields. PMID:24681238

Jang, Ji-Young; Moon, Sun-Young; Joo, Hong-Gu

2014-06-01

286

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

287

Cougar Population Dynamics and Viability in the  

Microsoft Academic Search

Increasing reports of human\\/cougar conflicts may suggest that cougars are increasing in the Pacific Northwest. We determined minimum relative densities and average fecundity, survival, and growth rate of an apparently increasing cougar population in northeastern Washington, USA; northern Idaho, USA; and southern British Columbia, Canada, from 1998 to 2003. Minimum relative densities declined from 1.47 cougars\\/ 100 km2 to 0.85

288

Peritoneal dialysis effluent, cytokine levels, and peritoneal mesothelial cell viability in CAPD: a possible relationship.  

PubMed

Recent studies have emphasized the role of peritoneal mesothelial cell (PMC) in peritoneal immune defense mechanisms in continuous ambulatory peritoneal dialysis (CAPD). The aim of this study was to evaluate a possible relationship between peritoneal dialysis effluent (PDE), cytokine (Cy) levels, and PMC viability and their impact on peritonitis morbidity. Fifteen patients initiating CAPD for end-stage renal failure participated in the study. The following parameters were evaluated: (1) the levels of interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), interleukin-6 (IL-6), and interleukin-8 (IL-8) in PDE samples taken 7 days after initiating CAPD, at the end of the first, third, and sixth month of CAPD (determined by a solid phase enzyme amplified sensitivity immunoassay EASIA); (2) peritoneal mesothelial cell viability [determined by the release of lactate dehydrogenase (LDH) and by trypan blue extrusion test] by isolating and culturing peritoneal mesothelial cells at the moment of the placement of the peritoneal catheter and at the sixth month of CAPD; (3) peritonitis incidence during the 24 months after starting CAPD. At the first month of CAPD in all patients there was a slight increase in PDE IL-1 beta and TNF-alpha levels, while other Cy were almost undetectable. Time course studies showed that in 10 patients (Group I) there was a significant increase in PDE levels of IL-6, IL-8, and INF-gamma (p < 0.0005) in comparison to other Cy and a good PMC viability. In the other 5 patients (Group II) there were higher PDE levels of IL-1 beta and TNF-alpha (p < 0.0005). This was associated with a marked reduction in PMC viability determined by the release of LDH and by the trypan blue extrusion test. During the 24 months after starting CAPD, incidence of peritonitis was one episode per 24 patient-months in Group I and one episode per 9.2 patient-months in Group II. Our results show that from the beginning of CAPD there are distinct patterns of Cy in the PDE that correlate with a different PMC viability and peritonitis morbidity. Thus the analysis of the above-mentioned parameters may be useful in the early identification of the risk of peritonitis, thus allowing preventive measures. PMID:9360642

Carozzi, S; Nasini, M G; Ravera, M; Sanna, A; Tirotta, A; Lamperi, S

1997-01-01

289

Hydrogen Supplementation of Preservation Solution Improves Viability of Osteochondral Grafts  

PubMed Central

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

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

2014-01-01

290

Economics of DAWT wind energy systems  

NASA Astrophysics Data System (ADS)

The results of a (DAWT) preliminary design investigation to assess the economic viability of its electrical energy generation are presented. Unit costs are estimated for three output ratings and for three different construction approaches. A limited production run of 100 to 500 units is considered for factory-built subassemblies and on-site final assembly and erection. Regional production centers are assumed within about 350 km (217 miles) of installation.

Foreman, K. M.

291

Species-specific viability analysis of Pseudomonas aeruginosa, Burkholderia cepacia and Staphylococcus aureus in mixed culture by flow cytometry  

PubMed Central

Background Bacterial species coexist commonly in mixed communities, for instance those occurring in microbial infections of humans. Interspecies effects contribute to alterations in composition of communities with respect to species and thus, to the course and severity of infection. Therefore, knowledge concerning growth and viability of single species in medically-relevant mixed communities is of high interest to resolve complexity of interspecies dynamics and to support development of treatment strategies. In this study, a flow cytometric method was established to assess the species-specific viability in defined three-species mixed cultures. The method enables the characterization of viability of Pseudomonas aeruginosa, Burkholderia cepacia and Staphylococcus aureus, which are relevant to lung infections of Cystic Fibrosis (CF) patients. The method combines fluorescence detection by antibody and lectin labeling with viability fluorescence staining using SYBR®Green I and propidium iodide. In addition, species-specific cell enumeration analysis using quantitative terminal restriction fragment length polymorphisms (qT-RFLP) was used to monitor the growth dynamics. Finally, to investigate the impact of substrate availability on growth and viability, concentrations of main substrates and metabolites released were determined. Results For each species, the time course of growth and viability during mixed culture cultivations was obtained by using qT-RFLP analysis in combination with flow cytometry. Comparison between mixed and pure cultures revealed for every species differences in growth properties, e.g. enhanced growth of P. aeruginosa in mixed culture. Differences were also observed for B. cepacia and S. aureus in the time course of viability, e.g. an early and drastic reduction of viability of S. aureus in mixed culture. Overall, P. aeruginosa clearly dominated the mixed culture with regard to obtained cell concentrations. Conclusions In combination with qT-RFLP analysis, the methods enabled monitoring of species-specific cell concentrations and viability during co-cultivation of theses strains. Experimental findings suggest that the predominance of P. aeruginosa over B. cepacia and S. aureus in mixed culture under the chosen cultivation conditions is promoted by more efficient substrate consumption of P. aeruginosa, and antagonistic interspecies effects induced by P. aeruginosa. PMID:24606608

2014-01-01

292

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

293

Engineered cerium oxide nanoparticles: Effects on bacterial growth and viability  

SciTech Connect

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

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

2010-01-01

294

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; Largiadčr, Stephanie; Schade, Grit

2011-02-01

295

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

296

Prospective evaluation of femoral head viability following femoral neck fracture  

SciTech Connect

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

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

1984-01-01

297

Detection and Viability of Lactococcus lactis throughout Cheese Ripening  

PubMed Central

Recent evidences highlighted the presence of Lactococcus lactis during late cheese ripening. For this reason, the role of this microorganism, well known as dairy starter, should be reconsidered throughout cheese manufacturing and ripening. Thus, the main objective of this study was to develop a RT-qPCR protocol for the detection, quantification and determination of the viability of L. lactis in ripened cheese samples by direct analysis of microbial nucleic acids. Standard curves were constructed for the specific quantification of L. lactis in cheese matrices and good results in terms of selectivity, correlation coefficient and efficiency were obtained. Thirty-three ripened cheeses were analyzed and, on the basis of RNA analysis, twelve samples showed 106 to 108 CFU of L. lactis per gram of product, thirteen from 103 to 105 CFU/g, and in eight cheeses, L. lactis was not detected. Traditional plating on M17 medium led to loads ranging from 105 to 109 CFU/g, including the cheese samples where no L. lactis was found by RT-qPCR. From these cheeses, none of the colonies isolated on M17 medium was identified as L. lactis species. These data could be interpreted as a lack of selectivity of M17 medium where colony growth is not always related to lactococcal species. At the same time, the absence or low abundance of L. lactis isolates on M17 medium from cheese where L. lactis was detected by RT-qPCR support the hypothesis that L. lactis starter populations are mainly present in viable but not culturable state during ripening and, for this reason, culture-dependent methods have to be supplemented with direct analysis of cheese. PMID:25503474

Cocolin, Luca

2014-01-01

298

Protein and carbohydrate intake influence sperm number and fertility in male cockroaches, but not sperm viability.  

PubMed

It is commonly assumed that because males produce many, tiny sperm, they are cheap to produce. Recent work, however, suggests that sperm production is not cost-free. If sperm are costly to produce, sperm number and/or viability should be influenced by diet, and this has been documented in numerous species. Yet few studies have examined the exact nutrients responsible for mediating these effects. Here, we quantify the effects of protein (P) and carbohydrate (C) intake on sperm number and viability in the cockroach Nauphoeta cinerea, as well as the consequences for male fertility. We found the intake of P and C influenced sperm number, being maximized at a high intake of diets with a P : C ratio of 1 : 2, but not sperm viability. The nutritional landscapes for male fertility and sperm number were closely aligned, suggesting that sperm number is the major determinant of male fertility in N. cinerea. Under dietary choice, males regulate nutrient intake at a P : C ratio of 1 : 4.95, which is midway between the ratios needed to maximize sperm production and pre-copulatory attractiveness in this species. This raises the possibility that males regulate nutrient intake to balance the trade-off between pre- and post-copulatory traits in this species. PMID:25608881

Bunning, Harriet; Rapkin, James; Belcher, Laurence; Archer, C Ruth; Jensen, Kim; Hunt, John

2015-03-01

299

Dead or Alive: Molecular Assessment of Microbial Viability  

PubMed Central

Nucleic acid-based analytical methods, ranging from species-targeted PCRs to metagenomics, have greatly expanded our understanding of microbiological diversity in natural samples. However, these methods provide only limited information on the activities and physiological states of microorganisms in samples. Even the most fundamental physiological state, viability, cannot be assessed cross-sectionally by standard DNA-targeted methods such as PCR. New PCR-based strategies, collectively called molecular viability analyses, have been developed that differentiate nucleic acids associated with viable cells from those associated with inactivated cells. In order to maximize the utility of these methods and to correctly interpret results, it is necessary to consider the physiological diversity of life and death in the microbial world. This article reviews molecular viability analysis in that context and discusses future opportunities for these strategies in genetic, metagenomic, and single-cell microbiology. PMID:25038100

Meschke, John S.

2014-01-01

300

Fever-Range Hyperthermia vs. Hypothermia Effect on Cancer Cell Viability, Proliferation and HSP90 Expression  

PubMed Central

Purpose The current study examines the effect of fever-range hyperthermia and mild hypothermia on human cancer cells focusing on cell viability, proliferation and HSP90 expression. Materials and Methods A549 and H1299 lung carcinoma, MCF7 breast adenocarcinoma, U87MG and T98G glioblastoma, DU145 and PC3 prostate carcinoma and MRC5 normal fetal lung fibroblasts cell lines were studied. After 3-day exposure to 34°C, 37°C and 40°C, cell viability was determined. Cell proliferation (ki67 index), apoptosis (Caspase 9) and HSP90 expression was studied by confocal microscopy. Results Viability/proliferation experiments demonstrated that MRC5 fibroblasts were extremely sensitive to hyperthermia, while they were the most resistant to hypothermia. T98G and A549 were thermo-tolerant, the remaining being thermo-sensitive to a varying degree. Nonetheless, as a universal effect, hypothermia reduced viability/proliferation in all cell lines. Hyperthermia sharply induced Caspase 9 in the U87MG most thermo-sensitive cell line. In T98G and A549 thermo-tolerant cell lines, the levels of Caspase 9 declined. Moreover, hyperthermia strongly induced the HSP90 levels in T98G, whilst a sharp decrease was recorded in the thermo-sensitive PC3 and U87MG cell lines. Hyperthermia sensitized thermo-sensitive cancer cell lines to cisplatin and temozolomide, whilst its sensitizing effect was diminished in thermo-tolerant cell lines. Conclusions The existence of thermo-tolerant and thermo-sensitive cancer cell lines was confirmed, which further encourages research to classify human tumor thermic predilection for patient stratification in clinical trials. Of interest, mild hypothermia had a universal suppressing effect on cancer cell proliferation, further supporting the radio-sensitization hypothesis through reduction of oxygen and metabolic demands. PMID:25635828

Kalamida, Dimitra; Karagounis, Ilias V.; Mitrakas, Achilleas; Kalamida, Sofia; Giatromanolaki, Alexandra; Koukourakis, Michael I.

2015-01-01

301

Economics and Hawaii's Marine Fisheries Introduction  

E-print Network

fishery is limited. Economic Values Determining the economic value of Hawaii's marine fisheries is not sim and recreational re sources and cultural practices, nor even a recitation of the kind of economic processes whichEconomics and Hawaii's Marine Fisheries Introduction Fishing and seafood consumption permeate

302

DETERMINE THE FEASIBILITY OF DEVELOPING A MODEL DESCRIBING THE FLOW OF OCCUPATIONAL AND ECONOMIC INFORMATION INTO THE SECONDARY VOCATIONAL-TECHNICAL SCHOOL. FINAL REPORT.  

ERIC Educational Resources Information Center

THE MAJOR OBJECTIVES OF THIS FEASIBILITY STUDY WERE (1) TO IDENTIFY INFORMATION SOURCES WHICH FURNISH OCCUPATIONAL AND ECONOMIC DATA TO SECONDARY SCHOOLS, (2) TO SELECT THOSE SOURCES WHICH ARE BELIEVED TO HAVE A MEASURABLE INFLUENCE ON THE VOCATIONAL CURRICULUM, AND (3) TO CATEGORIZE, RELATE, AND COMBINE OR RESTRUCTURE THOSE SOURCES INTO A…

SILVERN, LEONARD C.

303

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

SciTech Connect

The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO2 enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot CO2 project will demonstrate the economic viability and widespread applicability of CO2 flooding in fractured siliceous shale reservoirs of the San Joaquin Valley. The research consists of four primary work processes: (1) Reservoir Matrix and Fluid Characterization; (2) Fracture characterization; (3) reservoir Modeling and Simulation; and (4) CO2 Pilot Flood and Evaluation. Work done in these areas is subdivided into two phases or budget periods. The first phase of the project will focus on the application of a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work will be used to evaluate how the reservoir will respond to secondary recovery and EOR processes. The second phase of the project will include the implementation and evaluation of an advanced enhanced oil recovery (EOR) pilot in the United Anticline (West Dome) of the Buena Vista Hills Field.

Morea, Michael F.

1999-11-08

304

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

305

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

306

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

307

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

SciTech Connect

The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO2 enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot CO2 project will demonstrate the economic viability and widespread applicability of CO2 flooding in fractured siliceous shale reservoirs of the San Joaquin Valley. The research consists of four primary work processes: (1) Reservoir Matrix and Fluid Characterization; (2) Fracture characterization; (3) reservoir Modeling and Simulation; and (4) CO2 Pilot Flood and Evaluation. Work done in these areas is subdivided into two phases or budget periods. The first phase of the project will focus on the application of a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work will be used to evaluate how the reservoir will respond to secondary recovery and EOR processes. The second phase of the project will include the implementation and evaluation of an advanced enhanced oil recovery (EOR) pilot in the United Anticline (West Dome) of the Buena Vista Hills Field.

Morea, Michael F.

1999-11-01

308

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

309

Viability of free and encapsulated Escherichia coli overexpressing cyclopentanone monooxygenase monitored during model Baeyer-Villiger biooxidation by confocal laser scanning microscopy.  

PubMed

Baeyer-Villiger biooxidation of 4-methylcyclohexanone-5-methyloxepane-2-one catalysed by recombinant Escherichia coli overexpressing cyclopentanone monooxygenase encapsulated in polyelectrolyte complex capsules was used to investigate effect of substrate conversion on the viability of cells. Confocal laser scanning microscopy (CLSM) was used to assess cell viability using propidium iodide fluorescence marker for necrosis, and flavin autofluorescence to identify living bacteria. Viability of encapsulated cells decreased with increasing substrate concentration from 99 ± 1 to 83 ± 4%, while substrate conversions from decreased 100 to 6 ± 1%. Storage stabilization of encapsulated cells was observed by increased substrate conversion form 68 ± 2 to 96 ± 3%. Measurements by CLSM with standard deviations up to 5% may be regarded as powerful tool for recombinant cell viability determination during Baeyer-Villiger biooxidations. PMID:21983971

Schenkmayerová, Andrea; Bu?ko, Marek; Gemeiner, Peter; Chorvát, Dušan; Lacík, Igor

2012-02-01

310

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

PubMed Central

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

2012-01-01

311

A review of protocols for selecting species at risk in the context of US Forest Service viability assessments  

NASA Astrophysics Data System (ADS)

In December 2000, the USDA Forest Service (USFS) commissioned a review of their process for conducting viability assessments under the National Forest Management Act (NFMA). The objectives of the USFS review were to establish the scientific basis for geographic and temporal scales used in the assessment of viability, to identify and improve approaches that could be used to assess species viability within the context of NFMA, and to describe the strengths and limitations of the approaches used in the viability assessment process. In this paper, we present one aspect of this overall review: methods available and in use for selection of species at risk for the viability assessment process. A representative group of methods includes threatened and endangered species protocols such as the IUCN protocol, the Heritage ranks, the method devised by Millsap et al. (1990) to identify threatened and endangered species in Florida, as well as protocols for narrower taxonomic and geographic ranges. We provide a description of each of the nine protocols reviewed and compare them in terms of their taxonomic and geographic range, biological attributes, consideration of threats and population trends, data requirements, reliability and robustness, transparency and ability to deal with uncertainty. We found that all threatened and endangered species protocols are useful for classifying species at risk, however, those that explicitly include current and future threats are of most use in determining which species will be adversely affected by proposed management actions. We recommend that Heritage ranks be used to identify an initial set of candidate species for assessment of viability considerations, with further refinement and supplementation based on species distributions, relative to the scale of the planning area.

Andelman, Sandy J.; Groves, Craig; Regan, Helen M.

2004-10-01

312

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

Code of Federal Regulations, 2011 CFR

... 203.85 Section 203.85 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT...the Application, Review, Approval and Administration of the Deep Water Royalty Relief Program,” U.S. Department...

2011-07-01

313

Economic viability improvement of solar powered Indian rural banks through DC grids  

Microsoft Academic Search

Power shortages result in power outages for period of 8 to 10 Hrs a day in rural areas due to significant gap between electricity demand and supply. Rural banking is one of the sectors severely affected by power. Majority of population in emerging markets like India live in rural areas. Therefore, reliability and operational efficiency of rural banking is of

RakeshBabu Panguloori; PriyaRanjan Mishra; Ulrich Boeke

2011-01-01

314

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

315

Location of an agribusiness enterprise with respect to economic viability: a risk analysis  

E-print Network

affect the net cash income (NCI) and net present value (NPV). Alternative incentive packages affect the initial cost of investment for the production facility. Objective three is accomplished by using comparative scenario analysis in simulation.... Scenario analysis allows incorporation of alternative control variables to evaluate alternative choices. Stochastic simulation combined with scenario analysis will return distributions of alternative NPVs for each plant location. The results...

Lau, Michael H.

2006-04-12

316

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

317

Satellite power system: Engineering and economic analysis summary  

NASA Technical Reports Server (NTRS)

A system engineering and economic analysis was conducted to establish typical reference baselines for the photovoltaic, solar thermal, and nuclear satellite power systems. Tentative conclusions indicate that feasibility and economic viability are characteristic of the Satellite Power System. Anticipated technology related to manufacturing, construction, and maintenance operations is described. Fuel consumption, environmental effects, and orbital transfer are investigated. Space shuttles, local space transportation, and the heavy lift launch vehicle required are also discussed.

1976-01-01

318

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

319

ECONOMIC ASSESSMENT OF WASTE WATER AQUACULTURE TREATMENT SYSTEMS  

EPA Science Inventory

This study attempted to ascertain the economic viability of aquaculture as an alternative to conventional waste water treatment systems for small municipalities in the Southwestern region of the United States. A multiple water quality objective level cost-effectiveness model was ...

320

Viability changes: Microbiological analysis of dental casts  

PubMed Central

Background This study evaluated the survival of the most prevalent oral bacteria and fungi (Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, and Candida albicans) in dental casts, and compared changes in the amounts of these microorganisms at different time intervals to determine how long dental casts may pose threat to the health of dental personnel and patients. Material/Methods When manufacturing the casts, regular water was replaced with sterile distilled water, where suspensions of the studied bacteria or the fungus at certain concentrations were prepared. When the dental casts were fully set (solidified), plaster shavings were examined immediately after the contact of the studied microorganism with the plaster, as well as after 1, 2, 24, 48, 72, 96, and 120 hours. Following that, we measured how the amount of the studied bacteria and fungi in 1 gram of the plaster changed within the studied period of time. Results Klebsiella pneumoniae survived in plaster for up to 4 days, and the reduction in the number of these bacteria became statistically significant after 1 day (p<0.05). Staphylococcus aureus remained viable in plaster for up to 4 days, and the number of these bacteria dropped after 1 day (p<0.05). Escherichia coli disappeared after 2 days, and a reduction was already observed after 2 hours (p<0.05). Candida albicans in plaster models died within 2 days, and a reduction in their number was observed after 1 day (p<0.05). Conclusions The microorganisms did not multiply in the gypsum casts and their number significantly dropped instead of increasing. PMID:24902637

Žilinskas, Juozas; Junevi?ius, Jonas; Ramonait?, Agn?; Pavilonis, Alvydas; Gleiznys, Alvydas; Sakalauskien?, Jurgina

2014-01-01

321

III. Commercial viability of second generation biofuel technology27  

E-print Network

29 III. Commercial viability of second generation biofuel technology27 The previous chapters focused on first generation biofuels. In this chapter we focus on second generation biofuels, specifically biofuels derived from cellulosic or lignocellulosic conversion. Advocates for the development of cellulosic

322

Tree Squirrel Introduction: A Theoretical Approach with Population Viability Analysis  

Microsoft Academic Search

Reintroduction efforts require knowledge of how many animals are needed for successful establishment. Population viability analysis can be used to predict trajectories of introduced populations and tree squirrels provide an ideal model system to investigate this challenge. Conservation action is needed because more than 80% of species of tree squirrels are of precarious conservation status in some portion of their

David J. A. Wood; John L. Koprowski; Peter W. W. Lurz

2007-01-01

323

THE VIABILITY OF AIR TRANSPORTATION FOR PERISHABLE AGRICULTURAL PRODUCE  

Microsoft Academic Search

This paper evaluates the viability of air transportation for perishable agricultural products. In recent years, fruit has been the major perishable group of agricultural products to use this export option in Brazil, particularly the papaya. The focus of this research, then, will be the assessment of the production and the logistical processes involved the evaluation of the demand and the

Luiz Antonio Tozi; Carlos Muller

324

Evaluating the Viability of Mobile Learning to Enhance Management Training  

ERIC Educational Resources Information Center

A qualitative research project was conducted to test the viability of augmenting an e-learning program for workplace learners using mobile content delivered through smart phones. Ten learners taking a six week web-based e-learning course were given smart phones which enabled them to access approximately 70% of the course content, in addition to…

Macdonald, Iain; Chiu, Jason

2011-01-01

325

Assessment of Myocardial Viability in Patients with Heart Failure  

Microsoft Academic Search

The prognosis for patients with chronic ischemic left ventricular dysfunction is poor, despite advances in different therapies. Noninvasive assessment of myocardial viability may guide pa- tient management. Multiple imaging techniques have been developed to assess viable and nonviable myocardium by eval- uating perfusion, cell membrane integrity, mitochondria, glucose metabolism, scar tissue, and contractile reserve. PET, 201Tl and 99mTc scintigraphy, and

Arend F. L. Schinkel; Don Poldermans; Abdou Elhendy; Jeroen J. Bax

326

A Temperature-sensitive Calmodulin Mutant Loses Viability during Mitosis  

E-print Network

A Temperature-sensitive Calmodulin Mutant Loses Viability during Mitosis Trisha N. Davis Department and the large bud. After nuclear movement, mitosis and could form colonies in G1 and mitosis (Rasmussen and Means, 1989). Consistent with a role in mitosis, calmodulin

Davis, Trisha N.

327

Continued Viability of Universities as Centers for Basic Research.  

ERIC Educational Resources Information Center

The findings and 13 recommendations of a NSF Advisory Council task force that evaluated universities as centers of basic research are presented. Listed are the major strengths of universities as centers for basic research (including continuity and tradition, freedom of research, interactions among disciplines) and such threats to their viability

Carter, Lisle C., Jr.; And Others

328

EFFECT OF FUMIGATION ON VOLUNTEER POTATO (SOLANUM TUBERSOUM) TUBER VIABILITY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Management of volunteer potato requires an integrated approach and soil fumigation is one tactic known to reduce population densities of certain weeds. The effect of 1,3-D and metham sodium on potato tuber viability were tested in sealed glass jars at various doses, incubation temperatures, and tim...

329

Viability and Detectability of Photosynthesis on Earth-like Planets  

Microsoft Academic Search

Based on current understanding of how photosynthesis arose and developed on Earth,we consider what factors would limit or encourage the viability of photosynthetically energized organisms on Earth-like planets (ELP's) orbiting nearby ms stars with a range of surface temperature. Assuming that the ELP originally had an atmosphere similar to that of the early Earth and orbited within the parent star's

Ramon Wolstencroft; John Raven

2000-01-01

330

Effect of lanthanide complex structure on cell viability and association.  

PubMed

A systematic study of the effect of hydrophobicity and charge on the cell viability and cell association of lanthanide metal complexes is presented. The terbium luminescent probes feature a macrocyclic polyaminocarboxylate ligand (DOTA) in which the hydrophobicity of the antenna and that of the carboxyamide pendant arms are independently varied. Three sensitizing antennas were investigated in terms of their function in vitro: 2-methoxyisophthalamide (IAM(OMe)), 2-hydroxyisophthalamide (IAM), and 6-methylphenanthridine (Phen). Of these complexes, Tb-DOTA-IAM exhibited the highest quantum yield, although the higher cell viability and more facile synthesis of the structurally related Tb-DOTA-IAM(OMe) platform renders it more attractive. Further modification of this latter core structure with carboxyamide arms featuring hydrophobic benzyl, hexyl, and trifluoro groups as well as hydrophilic amino acid based moieties generated a family of complexes that exhibit high cell viability (ED50 > 300 ?M) regardless of the lipophilicity or the overall complex charge. Only the hexyl-substituted complex reduced cell viability to 60% in the presence of 100 ?M complex. Additionally, cellular association was investigated by ICP-MS and fluorescence microscopy. Surprisingly, the hydrophobic moieties did not increase cell association in comparison to the hydrophilic amino acid derivatives. It is thus postulated that the hydrophilic nature of the 2-methoxyisophthalamide antenna (IAM(OMe)) disfavors the cellular association of these complexes. As such, responsive luminescent probes based on this scaffold would be appropriate for the detection of extracellular species. PMID:24901440

Peterson, Katie L; Dang, Jonathan V; Weitz, Evan A; Lewandowski, Cutler; Pierre, Valérie C

2014-06-16

331

Evaluating Genetic Viability of Pronghorn in Wind Cave National Park  

E-print Network

155 Evaluating Genetic Viability of Pronghorn in Wind Cave National Park JONATHAN A. JENKS1 Cave National Park, 26611 U.S. Highway 385, Hot Springs, SD 57747 (DER) ABSTRACT -- The pronghorn existence of pronghorn inside Wind Cave National Park. Historically, pronghorn numbers reached greater than

332

SEED GERMINATION AND VIABILITY OF WYOMING SAGEBRUSH IN NORTHERN NEVADA  

Microsoft Academic Search

SUMMARY Seed size and germination behavior affect performance of early seedlings. The purpose of this study was to investigate rela- tionships between seed size and germination percentage, germina- tion rate, time course of germination and seed viability in Wyo- ming big sagebrush (Artemisia tridentata ssp. wyomingensis Beetle and Young). Working hypotheses were: 1) for single seeds, germination percentages and rates

Carlos A. Busso; Mónica Mazzola; Barry L. Perryman

2005-01-01

333

Dual fluorochrome flow cytometric assessment of yeast viability  

Technology Transfer Automated Retrieval System (TEKTRAN)

A novel staining protocol is reported for the assessment of viability in yeast, specifically the biocontrol yeast, Pichia anomala. Employing both the red fluorescent membrane potential sensitive oxonol stain DiBAC4(5) (Bis-(1,3-dibutylbarbituric acid)pentamethine oxonol), a structural analog of the ...

334

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

335

Economic evaluation of a solar hot-water system--Palm Beach County, Florida  

NASA Technical Reports Server (NTRS)

Report projects solar-energy costs and savings for residential hot-water system over 20 year period. Evaluation uses technical and economic models with inputs based on working characteristics of installed system. Primary analysis permits calculation of economic viability for four other U.S. sites.

1981-01-01

336

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

337

An economic assessment of STOL aircraft potential including terminal area environmental considerations. Volume 2: Appendices  

NASA Technical Reports Server (NTRS)

An economic assessment of short takeoff aircraft for short haul air transportation applications is presented. The economic viability and environmental compatibility of short takeoff aircraft service in high density areas were evaluated. The subjects discussed are: (1) aircraft configurations and performance, (2) airfield and terminal requirements, and (3) direct and indirect operating costs.

Solomon, H. L.; Sokolsky, S.

1973-01-01

338

Centre for Economic Performance  

NSDL National Science Digital Library

Established by the Economic and Social Research Council in 1990, the Centre for Economic Performance CEP at the London School of Economics and Political Science is one of the most prominent and established economic research groups in Europe. By focusing on the major links between globalization, technology and institutions, the CEP studies the determinants of economic performance at the level of the company, the nation, and the global economy. Broadly, CEP's research programs are divided into five groups that include research into labor markets, technology and growth, and education and skills. From the prodigious site, visitors can read about CEP In the News, learn about the various staff members' research areas of expertise, and browse their related publications (including occasional papers, working papers, and the like) back to 1990. Overall, this site will merit more than one visit, as it will be of substantial interest to persons interested in the intersections between economics, education, and globalization, to name but a few of the topical areas covered under the remit of the CEP.

339

Effects of hypothermic storage of striped bass (Morone saxatilis) sperm on intracellular calcium, reactive oxygen species formation, mitochondrial function, motility, and viability  

Technology Transfer Automated Retrieval System (TEKTRAN)

Experiments were conducted to determine the effect of hypothermic 24 h storage of striped bass sperm cells on viability, intracellular Ca2+ ([Ca2+]i), mitochondrial membrane potential (D'm), and reactive oxygen species (ROS) formation (oxidation of hydroethidine to ethidium) as determined by flow cy...

340

Corruption, Democracy, and Economic Growth  

Microsoft Academic Search

Scholars have long suspected that political processes such as democracy and corruption are important factors in determining economic growth. Studies show, however, that democracy has only indirect effects on growth, while corruption is generally accepted by scholars as having a direct and negative impact on economic performance. We argue that one of democracy's indirect benefits is its ability to mitigate

A. Cooper Drury; Jonathan Krieckhaus; Michael Lusztig

2006-01-01

341

A 'fragile cell' sub-population revealed during cytometric assessment of Saccharomyces cerevisiae viability in lipid-limited alcoholic fermentation.  

PubMed

Aims:? To show that in anaerobic fermentation with limiting lipid nutrients, cell preparation impacts the viability assessment of yeast cells, and to identify the factors involved. Methods and Results:? Saccharomyces cerevisiae viability was determined using propidium iodide staining and the flow cytometry. Analyses identified intact cells, dead cells and, under certain conditions, the presence of a third subpopulation of apparently damaged cells. This intermediate population could account for up to 40% of the entire cell population. We describe, analyse and discuss the effects of different solutions for cell resuspension on the respective proportion of these three populations, in particular that of the intermediate population. We show that this intermediate cell population forms in the absence of Ca(2+) /Mg(2+) . Conclusions:? Cell preparation significantly impacts population viability assessment by FCM. The intermediate population, revealed under certain conditions, could be renamed as 'fragile cells'. For these cells, Ca(2+) and Mg(2+) reduce cell membrane permeability to PI. Significance and Impact of the Study:? This is the first study that analyses and discusses the factors influencing the formation of an intermediate population when studying viability in yeast alcoholic fermentation. With a wider application in biological research, this study provides important support to the relatively new questioning of propidium iodide staining as a universal cell death indicator. PMID:22909384

Delobel, P; Pradal, M; Blondin, B; Tesniere, C

2012-08-21

342

Investigation into the power of multinational corporations and an anallytical evaluation of the determinants of US foreign direct investment in the European economic community: a special case of multinational oil companies  

SciTech Connect

This study provides historical background on, and explores the philosophy, motivation and nature of, capital movement in general and the role of multinational oil companies in European countries in particular. Also, theoretical and statistical models are developed to determine the major factors affecting the flow of foreign direct investment and to analyze the economic impact of this flow. The study concludes that there are many quantitative as well as non-quantitative factors of various socio-economic and political natures that determine the flows of direct investment abroad. The empirical results, based on yearly data for the period of 1950 to 1979, indicate that, among many variables tested in the model, seven are statistically significant in determining the amount of US direct investment abroad. These variables are: the level of output produced by the affiliates of the US companies in host countries, the US interest rate, retained earnings by the affiliates of the US companies, size of the host market, tariff discrimination, wage differentials and growth of the host market. On the question of the welfare effect of foreign direct investment, it is concluded that developed host nations tend to gain more from foreign direct investment than do other less-developed host countries.

Motavasseli, M.

1982-01-01

343

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. PMID:22778923

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

2012-01-01

344

Airship economics  

NASA Technical Reports Server (NTRS)

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

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

1975-01-01

345

The Effect of Tuning Cold Plasma Composition on Glioblastoma Cell Viability  

PubMed Central

Previous research in cold atmospheric plasma (CAP) and cancer cell interaction has repeatedly proven that the cold plasma induced cell death. It is postulated that the reactive oxygen species (ROS) and reactive nitrogen species (RNS) play a major role in the CAP cancer therapy. In this paper, we seek to determine a mechanism of CAP therapy on glioblastoma cells (U87) through an understanding of the composition of the plasma, including treatment time, voltage, flow-rate and plasma-gas composition. In order to determine the threshold of plasma treatment on U87, normal human astrocytes (E6/E7) were used as the comparison cell line. Our data showed that the 30 sec plasma treatment caused 3-fold cell death in the U87 cells compared to the E6/E7 cells. All the other compositions of cold plasma were performed based on this result: plasma treatment time was maintained at 30 s per well while other plasma characteristics such as voltage, flow rate of source gas, and composition of source gas were changed one at a time to vary the intensity of the reactive species composition in the plasma jet, which may finally have various effect on cells reflected by cell viability. We defined a term “plasma dosage” to summarize the relationship of all the characteristics and cell viability. PMID:24878760

Cheng, Xiaoqian; Sherman, Jonathan; Murphy, William; Ratovitski, Edward; Canady, Jerome; Keidar, Michael

2014-01-01

346

Mammalian cell viability in electrospun composite nanofiber structures.  

PubMed

Incorporation of mammalian cells into nanofibers (cell electrospinning) and multilayered cell-nanofiber structures (cell layering) via electrospinning are promising techniques for tissue engineering applications. We investigate the viability of 3T3-L1 mouse fibroblasts after incorporation into poly(vinyl alcohol) nanofibers and multilayering with poly(caprolactone) nanofibers and analyze the possible factors that affect cell viability. We observe that cells do not survive cell electrospinning but survive cell layering. Assessing the factors involved in cell electrospinning, we find that dehydration and fiber stretching are the main causes of cell death. In cell layering, the choice of solvent is critical, as residual solvent in the electrospun fibers could be detrimental to the cells. PMID:21984502

Canbolat, Mehmet Fatih; Tang, Christina; Bernacki, Susan H; Pourdeyhimi, Behnam; Khan, Saad

2011-10-10

347

Cosmological viability conditions for f(T) dark energy models  

SciTech Connect

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., E-mail: rezakord@ipm.ir, E-mail: N.Mohammadipour@uok.ac.ir [Department of Science, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

2012-11-01

348

Hybrid Viability and Fertility in Co-occuring Plant Species  

NASA Astrophysics Data System (ADS)

Similar species of plants can co-exist due to reproductive barriers that keep them from hybridizing. In the case of Lasthenia gracilis and L. californica, certain reproductive barriers allow them to co-exist at Jasper Ridge without hybridization. The two species are locally adapted to different regions of the same hillside, and have slight differences in flowering time but hybrids can be created at low rate in the green house. We tested the viability and fertility of green house produced hybrids to quantify post-zygotic reproductive isolation at Jasper Ridge. We planted 10 hybrid seeds and 10 control seeds from 11 different families. We measured the percent germination, survival to flowering and pollen fertility of the seeds. We expect lower germination, lower survival to flowering, and lower pollen viability of hybrid seeds as compared to control seeds.

Hernandez, E.; Garcia, C.; Yost, J.

2012-12-01

349

Some economic tables for airships  

NASA Technical Reports Server (NTRS)

During the course of the Southern California Aviation Council study on lighter than air it was determined that some form of economic base must be developed for estimation of costs of the airship. The tables are presented.

Neumann, R. D.

1975-01-01

350

Viability of Cururbita pepo pollen: biophysical and structural data  

Microsoft Academic Search

During ageing of the short-lived pollen grains of Cucurbita pepo L., water loss was examined in relation to viability using biophysical (1H-nuclear magnetic resonance, NMR) and cytological methods (fluorochromatic reaction test, freezefracture and scanning electron microscopy). A semi-logarithmic representation of the pollen weight loss demonstrated the complexity of the dehydration process. A the study of proton loss using 1H-NMR indicated

Catherine Digonnet-Kerhoas; Gilles Gay; Jean Claude Duplan; Christian Dumas

1989-01-01

351

Measurable Viability Theorems and the Hamilton-Jacobi-Bellman Equation  

Microsoft Academic Search

We prove viability and invariance theorems for systems with dynamics depending on time in a measurable way and having time dependent state constraints: x?(t) ? F(t, x(t)), x(t) ? P(t). In the above t ? P(t) is an absolutely continuous set-valued map and (t, x) ? F(t, x) is a set-valued map which is measurable with respect to t and

H. Frankowska; S. Plaskacz; T. Rzezuchowski

1995-01-01

352

Regional population viability of grassland songbirds: Effects of agricultural management  

Microsoft Academic Search

Although population declines of grassland songbirds in North America and Europe are well-documented, the effect of local processes on regional population persistence is unclear. To assess population viability of grassland songbirds at a regional scale (?150,000ha), we quantified Savannah Sparrow Passerculus sandwichensis and Bobolink Dolichonyx oryzivorus annual productivity, adult apparent survival, habitat selection, and density in the four most (regionally)

Noah G. Perlut; Allan M. Strong; Therese M. Donovan; Neil J. Buckley

2008-01-01

353

Cartilage viability after repetitive loading: a preliminary report  

Microsoft Academic Search

Objective To assess matrix changes and chondrocyte viability during static and continuous repetitive mechanical loading in mature bovine articular cartilage explants.MethodsCartilage explants were continuously loaded either statically or cyclically (0.5Hz) for 1–72h (max. stress 1megapascal). Cell death was assessed using fluorescent probes and detection of DNA strand breakage characteristic of apoptosis. Cell morphology and matrix integrity were evaluated using histology

E. Lucchinetti; C. S. Adams; W. E. Horton; P. A. Torzilli

2002-01-01

354

Viability of Homozygous Deficiencies in Somatic Cells of DROSOPHILA MELANOGASTER  

PubMed Central

The viability of cells made homozygous for different deficiencies by induced mitotic recombination was examined. The deficiencies varied in length from two to 30 polytene chromosome bands and were distributed over the five major chromosome arms. Among a sample of 30, ten deficiencies were cell viable. Our results show that 12% of the genome is necessary for cell survival, supporting previous estimates of about 5,000 genes in the genome of Drosophila. PMID:17248892

Ripoll, Pedro; García-Bellido, A.

1979-01-01

355

Assessing population viability while accounting for demographic and environmental uncertainty.  

PubMed

Predicting the future trend and viability of populations is an essential task in ecology. Because many populations respond to changing environments, uncertainty surrounding environmental responses must be incorporated into population assessments. However, understanding the effects of environmental variation on population dynamics requires information on several important demographic parameters that are often difficult to estimate. Integrated population models facilitate the integration of time series data on population size and all existing demographic information from a species, allowing the estimation of demographic parameters for which limited or no empirical data exist. Although these models are ideal for assessments of population viability, they have so far not included environmental uncertainty. We incorporated environmental variation in an integrated population model to account for both demographic and environmental uncertainty in an assessment of population viability. In addition, we used this model to estimate true juvenile survival, an important demographic parameter for population dynamics that is difficult to estimate empirically. We applied this model to assess the past and future population trend of a rare island endemic songbird, the Montserrat Oriole Icterus oberi, which is threatened by volcanic activity. Montserrat Orioles experienced lower survival in years with volcanic ashfall, causing periodic population declines that were compensated by higher seasonal fecundity in years with high pre-breeding season rainfall. Due to the inclusion of both demographic and environmental uncertainty in the model, the estimated population growth rate in the immediate future was highly imprecise (95% credible interval 0.844-1.105), and the probability of extinction after three generations (in the year 2028) was low (2.1%). This projection demonstrates that accounting for both demographic and environmental sources of uncertainty provides a more realistic assessment of the viability of populations under unknown future environmental conditions. PMID:25163115

Oppel, Steffen; Hilton, Geoff; Ratcliffe, Norman; Fenton, Calvin; Daley, James; Gray, Gerard; Vickery, Juliet; Gibbons, David

2014-07-01

356

Population viability impacts of habitat additions and subtractions: A simulation experiment with endangered kangaroo rats  

EPA Science Inventory

Species viability is influenced by the quality, quantity and configuration of habitat. For species at risk, a principal challenge is to identify landscape configurations that, if realized, would improve a population?s viability or restoration potential. Critical habitat patche...

357

45 CFR 1302.20 - Grantee to show both legal status and financial viability.  

Code of Federal Regulations, 2010 CFR

...substantial diminution of the financial resources of a grantee...to have legal status and financial viability. Failure to...grantee in writing of the decision as to the grantee's legal status and financial viability within 30...

2010-10-01

358

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

359

Economic impact  

SciTech Connect

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

Technology Transfer Department

2001-06-01

360

Economic Growth  

Microsoft Academic Search

How can society improve its living standards? What are the conditions necessary for prosperity? These are the questions that define the essence of growth theory. In this user-friendly book, Olivier de la Grandville provides a fascinating introduction to the theory of economic growth and shows how many results from this field are of paramount importance for society. The classical mechanics

Olivier de la Grandville

361

Basketball Economics.  

ERIC Educational Resources Information Center

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

Scheinman, Daniel; Scheinman, Ted

362

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

PubMed Central

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

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

2015-01-01

363

Viability of Cururbita pepo pollen: biophysical and structural data.  

PubMed

During ageing of the short-lived pollen grains of Cucurbita pepo L., water loss was examined in relation to viability using biophysical ((1)H-nuclear magnetic resonance, NMR) and cytological methods (fluorochromatic reaction test, freezefracture and scanning electron microscopy). A semi-logarithmic representation of the pollen weight loss demonstrated the complexity of the dehydration process. A the study of proton loss using (1)H-NMR indicated that two major releases water of had taken place, each with different flux rates. Pulse (1)H-NMR experiments showed the occurrene of non-exponential signal decay as a function of time, indicating the existence of different fractions of water in a pollen grain sample. These fractions leave the pollen grain at different times during pollen dehydration, and one of them (that of the so-called "vital water") can be related to pollen viability. The quantity of protons giving a signal during pulse (1)H-NMR experiments was very low when the pollen grains were judged to be dead according to the fluorochromatic test. Freeze-fracture replicas of these dead pollen grains (less than 25% water content) showed that the plasma membrane had become detached from the intine surface; this ultrastructural feature might therefore be involved in the loss of pollen viability. PMID:24201515

Digonnet-Kerhoas, C; Gay, G; Duplan, J C; Dumas, C

1989-09-01

364

Inhibiting ice recrystallization and optimization of cell viability after cryopreservation.  

PubMed

The ice recrystallization inhibition activity of various mono- and disaccharides has been correlated with their ability to cryopreserve human cell lines at various concentrations. Cell viabilities after cryopreservation were compared with control experiments where cells were cryopreserved with dimethylsulfoxide (DMSO). The most potent inhibitors of ice recrystallization were 220 mM solutions of disaccharides; however, the best cell viability was obtained when a 200 mM d-galactose solution was utilized. This solution was minimally cytotoxic at physiological temperature and effectively preserved cells during freeze-thaw. In fact, this carbohydrate was just as effective as a 5% DMSO solution. Further studies indicated that the cryoprotective benefit of d-galactose was a result of its internalization and its ability to mitigate osmotic stress, prevent intracellular ice formation and/or inhibit ice recrystallization. This study supports the hypothesis that the ability of a cryoprotectant to inhibit ice recrystallization is an important property to enhance cell viability post-freeze-thaw. This cryoprotective benefit is observed in three different human cell lines. Furthermore, we demonstrated that the ability of a potential cryoprotectant to inhibit ice recrystallation may be used as a predictor of its ability to preserve cells at subzero temperatures. PMID:21852258

Chaytor, Jennifer L; Tokarew, Jacqueline M; Wu, Luke K; Leclčre, Mathieu; Tam, Roger Y; Capicciotti, Chantelle J; Guolla, Louise; von Moos, Elisabeth; Findlay, C Scott; Allan, David S; Ben, Robert N

2012-01-01

365

Different effects of sonoporation on cell morphology and viability  

PubMed Central

The objective of our study was to investigate changes in cell morphology and viability after sonoporation. Sonoportion was achieved by ultrasound (21 kHz) exposure on adherent human prostate cancer DU145 cells in the cell culture dishes with the presence of microbubble contrast agents and calcein (a cell impermeant dye). We investigated changes in cell morphology immediately after sonoporation under scanning electron microscope (SEM) and changes in cell viability immediately and 6 h after sonoporation under fluorescence microscope. It was shown that various levels of intracellular calcein uptake and changes in cell morphology can be caused immediately after sonoporation: smooth cell surface, pores in the membrane and irregular cell surface. Immediately after sonoporation, both groups of cells with high levels of calcein uptake and low levels of calcein uptake were viable; 6 h after sonoporation, group of cells with low levels of calcein uptake still remained viable, while group of cells with high levels of calcein uptake died. Sonoporation induces different effects on cell morphology, intracellular calcein uptake and cell viability PMID:22642588

Zhang, Ji-Zhen; Saggar, Jasdeep K.; Zhou, Zhao-Li; Bing-Hu

2012-01-01

366

A simplified economic filter for open-pit mining and heap-leach recovery of copper in the United States  

USGS Publications Warehouse

Determining the economic viability of mineral deposits of various sizes and grades is a critical task in all phases of mineral supply, from land-use management to mine development. This study evaluates two simple tools for estimating the economic viability of porphyry copper deposits mined by open-pit, heap-leach methods when only limited information on these deposits is available. These two methods are useful for evaluating deposits that either (1) are undiscovered deposits predicted by a mineral resource assessment, or (2) have been discovered but for which little data has been collected or released. The first tool uses ordinary least-squared regression analysis of cost and operating data from selected deposits to estimate a predictive relationship between mining rate, itself estimated from deposit size, and capital and operating costs. The second method uses cost models developed by the U.S. Bureau of Mines (Camm, 1991) updated using appropriate cost indices. We find that the cost model method works best for estimating capital costs and the empirical model works best for estimating operating costs for mines to be developed in the United States.

Long, Keith R.; Singer, Donald A.

2001-01-01

367

Preoperative Positron Emission Tomographic Viability Assessment and Perioperative and Postoperative Risk in Patients With Advanced Ischemic Heart Disease  

Microsoft Academic Search

Objectives. This study sought to investigate whether determination of tissue viability by means of positron emission tomography (PET) before coronary artery bypass graft surgery (CABG) affects clinical outcome with respect to both in-hospital mortality and 1-year survival rate.Background. Patients with coronary artery disease (CAD) and severe left ventricular (LV) dysfunction are at higher risk for perioperative complications associated with CABG.

Felix Haas; Christoph J Haehnel; Wolfgang Picker; Stephan Nekolla; Stefan Martinoff; Hans Meisner; Markus Schwaiger

1997-01-01

368

Correlation of visual in vitro cytotoxicity ratings of biomaterials with quantitative in vitro cell viability measurements.  

PubMed

Medical devices and implanted biomaterials are often assessed for biological reactivity using visual scores of cell-material interactions. In such testing, biomaterials are assigned cytotoxicity ratings based on visual evidence of morphological cellular changes, including cell lysis, rounding, spreading, and proliferation. For example, ISO 10993 cytotoxicity testing of medical devices allows the use of a visual grading scale. The present study compared visual in vitro cytotoxicity ratings to quantitative in vitro cytotoxicity measurements for biomaterials to determine the level of correlation between visual scoring and a quantitative cell viability assay. Biomaterials representing a spectrum of biological reactivity levels were evaluated, including organo-tin polyvinylchloride (PVC; a known cytotoxic material), ultra-high molecular weight polyethylene (a known non-cytotoxic material), and implantable tissue adhesives. Each material was incubated in direct contact with mouse 3T3 fibroblast cell cultures for 24 h. Visual scores were assigned to the materials using a 5-point rating scale; the scorer was blinded to the material identities. Quantitative measurements of cell viability were performed using a 3-(4,5-dimethylthiozol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay; again, the assay operator was blinded to material identities. The investigation revealed a high degree of correlation between visual cytotoxicity ratings and quantitative cell viability measurements; a Pearson's correlation gave a correlation coefficient of 0.90 between the visual cytotoxicity score and the percent viable cells. An equation relating the visual cytotoxicity score and the percent viable cells was derived. The results of this study are significant for the design and interpretation of in vitro cytotoxicity studies of novel biomaterials. PMID:17932777

Bhatia, Sujata K; Yetter, Ann B

2008-08-01

369

Ketone supplementation decreases tumor cell viability and prolongs survival of mice with metastatic cancer.  

PubMed

Cancer cells express an abnormal metabolism characterized by increased glucose consumption owing to genetic mutations and mitochondrial dysfunction. Previous studies indicate that unlike healthy tissues, cancer cells are unable to effectively use ketone bodies for energy. Furthermore, ketones inhibit the proliferation and viability of cultured tumor cells. As the Warburg effect is especially prominent in metastatic cells, we hypothesized that dietary ketone supplementation would inhibit metastatic cancer progression in vivo. Proliferation and viability were measured in the highly metastatic VM-M3 cells cultured in the presence and absence of ?-hydroxybutyrate (?HB). Adult male inbred VM mice were implanted subcutaneously with firefly luciferase-tagged syngeneic VM-M3 cells. Mice were fed a standard diet supplemented with either 1,3-butanediol (BD) or a ketone ester (KE), which are metabolized to the ketone bodies ?HB and acetoacetate. Tumor growth was monitored by in vivo bioluminescent imaging. Survival time, tumor growth rate, blood glucose, blood ?HB and body weight were measured throughout the survival study. Ketone supplementation decreased proliferation and viability of the VM-M3 cells grown in vitro, even in the presence of high glucose. Dietary ketone supplementation with BD and KE prolonged survival in VM-M3 mice with systemic metastatic cancer by 51 and 69%, respectively (p < 0.05). Ketone administration elicited anticancer effects in vitro and in vivo independent of glucose levels or calorie restriction. The use of supplemental ketone precursors as a cancer treatment should be further investigated in animal models to determine potential for future clinical use. PMID:24615175

Poff, A M; Ari, C; Arnold, P; Seyfried, T N; D'Agostino, D P

2014-10-01

370

Effects of L-carnitine on leukocyte function and viability in hemodialysis patients: A double-blind randomized trial.  

PubMed

Excess morbidity and mortality among long-term hemodialysis patients because of infectious complications is partly caused by an impairment of cellular immune defense. We hypothesized this impairment is related to an abnormal carnitine metabolism also present in these patients. In a double-blind, randomized, placebo-controlled trial, we investigated the effect of L-carnitine on phagocytic function and viability of blood leukocytes in 17 patients undergoing maintenance hemodialysis. After an observation period of 1 month, the patients received either 10 mg/kg of L-carnitine or placebo intravenously at the end of each hemodialysis session over a period of 4 months. Leukocyte oxidative metabolism was measured by means of luminol-enhanced chemiluminescence and superoxide generation after stimulation with Staphylococcus aureus or phorbol myristate acetate. Killing capacity and phagocytosis of radiolabeled staphylococci were determined. A lactate dehydrogenase (LDH) release test was applied to assess cell viability. We were unable to show an effect of L-carnitine on phagocytic function and viability in vivo. Several clinical parameters were observed during the trial. No statistically significant differences concerning dialysis-related morbidity, anemia, or reduction of blood urea nitrogen and creatinine levels were detected. Additionally, we tested the effect of L-carnitine on phagocytic function after in vitro incubation of blood leukocytes, which also showed no changes. LDH release was decreased, indicating an improved viability of these cells. The latter results were found after in vitro incubation of cells, but could not be confirmed in vivo. In summary, we could not show beneficial effects of L-carnitine administration in hemodialysis patients for the dosage and duration of treatment stated, either on phagocytic function and viability or on the clinical and biochemical parameters observed. PMID:10516349

Thomas, S; Fischer, F P; Mettang, T; Pauli-Magnus, C; Weber, J; Kuhlmann, U

1999-10-01

371

Spore Density and Viability of Entomopathogenic Fungal Isolates from Indonesia, and Their Virulence against Aphis gossypii Glover (Homoptera: Aphididae)  

PubMed Central

The focus of this study was on quantifying fitness attributes, such as spore density and viability, and determining the virulence level against aphid (Aphis gossypii) nymphs of isolates from the fungal species Beauveria bassiana and Metarhizium anisopliae. The fungal isolates were obtained from several insects, including Plutella xylostella, Hypothenemus hampei, Bronstispa longissima, A. gossypii, Tenebrio molitor, and Leptocorisa acuta, that were collected from Indonesian islands, such as Sumatera, Java, and Sulawesi. Third instar aphid nymphs were inoculated via topical application of 106 conidia ml?1 of the entomopathogenic fungal isolates. All of the B. bassiana and M. anisopliae isolates could produce very dense spores. The M. anisopliae isolate MaAg, which was obtained from the aphid, had the highest spore density at 6.70 × 108 conidia ml?1. Among the B. bassiana isolates, the highest conidial viability belonged to isolate CPJW8, which was obtained from Chrysodeixis chalcites, with a 39% average viability. Among the M. anisopliae isolates, the highest viabilities belonged to the isolates MaAg and MaLa, which were obtained from L. acuta, with a 33% and 32% average viabilities, respectively. All of the B. bassiana and M. anisopliae isolates were virulent against aphid nymphs, with mortality rates ranging from 64% to 94%. The three most virulent isolates were BBY715 (94%), MPx (92%), and MaTm (92%), and the least virulent isolate was MaLa (64%). BBY715, the most virulent isolate, had the shortest lethal time median (LT50) against aphid nymphs at 2.97 hours, and MaLa had the longest LT50 at 61.81 hours. PMID:24575186

Herlinda, Siti

2010-01-01

372

Viability of Cladosporium herbarum spores under 157?nm laser and vacuum ultraviolet irradiation, low temperature (10?K) and vacuum  

SciTech Connect

Ultraviolet photons can damage microorganisms, which rarely survive prolonged irradiation. In addition to the need for intact DNA, cell viability is directly linked to the functionality of the cell wall and membrane. In this work, Cladosporium herbarum spore monolayers exhibit high viability (7%) when exposed to 157?nm laser irradiation (412 kJm{sup ?2}) or vacuum-ultraviolet irradiation (110–180?nm) under standard pressure and temperature in a nitrogen atmosphere. Spore viability can be determined by atomic-force microscopy, nano-indentation, mass, ?-Raman and attenuated reflectance Fourier-transform far-infrared spectroscopies and DNA electrophoresis. Vacuum ultraviolet photons cause molecular damage to the cell wall, but radiation resistance in spores arises from the activation of a photon-triggered signaling reaction, expressed via the exudation of intracellular substances, which, in combination with the low penetration depth of vacuum-ultraviolet photons, shields DNA from radiation. Resistance to phototoxicity under standard conditions was assessed, as was resistance to additional environmental stresses, including exposure in a vacuum, under different rates of change of pressure during pumping time and low (10?K) temperatures. Vacuum conditions were far more destructive to spores than vacuum-ultraviolet irradiation, and UV-B photons were two orders of magnitude more damaging than vacuum-ultraviolet photons. The viability of irradiated spores was also enhanced at 10?K. This work, in addition to contributing to the photonic control of the viability of microorganisms exposed under extreme conditions, including decontamination of biological warfare agents, outlines the basis for identifying bio-signaling in vivo using physical methodologies.

Sarantopoulou, E., E-mail: esarant@eie.gr; Stefi, A.; Kollia, Z.; Palles, D.; Cefalas, A. C. [National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, Athens 11635 (Greece); Petrou, P. S.; Bourkoula, A.; Koukouvinos, G.; Kakabakos, S. [N.C.S.R. “Demokritos”, Institute for Nuclear and Radiological Sciences, Energy, Technology and Safety, Patriarchou Gregoriou Str. Aghia Paraskevi, Athens 15310 (Greece); Velentzas, A. D. [University of Athens, Faculty of Biology, Department of Cell Biology and Biophysics, Athens 15784 (Greece)

2014-09-14

373

Viability of Cladosporium herbarum spores under 157 nm laser and vacuum ultraviolet irradiation, low temperature (10 K) and vacuum  

NASA Astrophysics Data System (ADS)

Ultraviolet photons can damage microorganisms, which rarely survive prolonged irradiation. In addition to the need for intact DNA, cell viability is directly linked to the functionality of the cell wall and membrane. In this work, Cladosporium herbarum spore monolayers exhibit high viability (7%) when exposed to 157 nm laser irradiation (412 kJm-2) or vacuum-ultraviolet irradiation (110-180 nm) under standard pressure and temperature in a nitrogen atmosphere. Spore viability can be determined by atomic-force microscopy, nano-indentation, mass, ?-Raman and attenuated reflectance Fourier-transform far-infrared spectroscopies and DNA electrophoresis. Vacuum ultraviolet photons cause molecular damage to the cell wall, but radiation resistance in spores arises from the activation of a photon-triggered signaling reaction, expressed via the exudation of intracellular substances, which, in combination with the low penetration depth of vacuum-ultraviolet photons, shields DNA from radiation. Resistance to phototoxicity under standard conditions was assessed, as was resistance to additional environmental stresses, including exposure in a vacuum, under different rates of change of pressure during pumping time and low (10 K) temperatures. Vacuum conditions were far more destructive to spores than vacuum-ultraviolet irradiation, and UV-B photons were two orders of magnitude more damaging than vacuum-ultraviolet photons. The viability of irradiated spores was also enhanced at 10 K. This work, in addition to contributing to the photonic control of the viability of microorganisms exposed under extreme conditions, including decontamination of biological warfare agents, outlines the basis for identifying bio-signaling in vivo using physical methodologies.

Sarantopoulou, E.; Stefi, A.; Kollia, Z.; Palles, D.; Petrou, P. S.; Bourkoula, A.; Koukouvinos, G.; Velentzas, A. D.; Kakabakos, S.; Cefalas, A. C.

2014-09-01

374

Pollen viability and storage temperature for Southern highbush and Rabbiteye blueberry breeding  

Technology Transfer Automated Retrieval System (TEKTRAN)

Pollen viability, as measured by tetrad germination, has been reported, but these studies focused on freshly collected pollen and did not address viability of pollen stored at different temperatures over time. Moreover, genetic differences in pollen viability have been reported in blueberry genotype...

375

Automated Selection of Interaction Effects in Sparse Kernel Methods to Predict Pregnancy Viability  

E-print Network

Automated Selection of Interaction Effects in Sparse Kernel Methods to Predict Pregnancy Viability the viability of pregnancies at the end of the first trimester based on initial scan findings. I. INTRODUCTION the proposed method on the prediction of the viability of pregnancies at the end of the first trimester, based

376

Viability Kernel for Ecosystem Management Models Eladio Oca~na Anaya  

E-print Network

Viability Kernel for Ecosystem Management Models Eladio Oca~na Anaya Michel De Lara Ricardo task in general. We study the viability of nonlinear generic ecosystem models under preservation in the Peruvian upwelling ecosystem. Key words: control theory; state constraints; viability; predator

Paris-Sud XI, Université de

377

Viability of Rural Banking by The Nationalized Commercial Banks in India  

Microsoft Academic Search

This paper examines the viability of rural banking by the Nationalized Commercial Banks and the factors influencing it. The viability was examined using both cost and profitability analyses. Theory of costs is used for the former, while multi-variate econometric model is formulated for the latter. Factors influencing viability in both the analysis are classified into innovative and non-innovative based on

Bhattacharjee Sourindra; Desai B M; Naik Gopal

378

Economic method and economic rhetoric  

Microsoft Academic Search

McCloskey's work on the rhetoric of economics has little to say about Imre Lakatos, and indeed the scientific method prescribed by Lakatos, as it stands, would support McCloskey's claim that philosophers’ imperatives bear little relation to what economists actually do. But a Bayesianized version of Lakatos is a different matter, and provides a yardstick against which the various rhetorical devices

John Maloney

1994-01-01

379

Economic assessment.  

PubMed

The RCN and the Office for Public Management (OPM) are working together to provide training in how to perform economic assessments and use economic evidence to demonstrate the value of nurse-led innovation. This is a leadership development opportunity, supported by the Burdett Trust for Nursing, which provides participants with: knowledge, skills and confidence to lead and demonstrate the value of person-centred service innovations; the ability to support others doing the same; an Institute of Leadership & Management (ILM) certificate; and the support of the RCN and its networks to share the innovations in a variety of formats with a range of stakeholders. Applicants must be leading a service innovation and be able to secure sponsorship from their employer. The closing date for this round of applications is April 28. For more information and an application form, go to tinyurl.com/p53f6r9. PMID:25727434

2015-03-01

380

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

381

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

2004-03-01

382

Effect of KCl substitution on bacterial viability of Escherichia coli (ATCC 25922) and selected probiotics.  

PubMed

Excessive intake of NaCl has been associated with the increased risk of several diseases, particularly hypertension. Strategies to reduce sodium intake include substitution of NaCl with other salts, such as KCl. In this study, the effects of NaCl reduction and its substitution with KCl on cell membranes of a cheese starter bacterium (Lactococcus lactis ssp. lactis), probiotic bacteria (Bifidobacterium longum, Lactobacillus acidophilus, and Lactobacillus casei), and a pathogenic bacterium (Escherichia coli) were investigated using Fourier-transform infrared (FTIR) spectroscopy. A critical NaCl concentration that inhibited the viability of E. coli without affecting the viability of probiotic bacteria significantly was determined. To find the critical NaCl concentration, de Man, Rogosa, and Sharpe (MRS) broth was supplemented with a range of NaCl concentrations [0 (control), 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0%], and the effect on cell viability and FTIR spectra was monitored for all bacteria. A NaCl concentration of 2.5% was found to be the critical level of NaCl to inhibit E. coli without significantly affecting the viability of most of the probiotic bacteria and the cheese starter bacterium. The FTIR spectral analysis also highlighted the changes that occurred mainly in the amide regions upon increasing the NaCl concentration from 2.5 to 3.0% in most of the bacteria. Escherichia coli and B. longum were more sensitive to substitution of NaCl with KCl, compared with Lb. acidophilus, Lb. casei, and Lc. lactis ssp. lactis. To evaluate the effect of substitution of NaCl with KCl, substitution was carried out at the critical total salt concentration (2.5%, wt/vol) at varying concentrations (0, 25, 50, 75, and 100% KCl). The findings suggest that 50% substitution of NaCl with KCl, at 2.5% total salt, could inhibit E. coli without affecting the probiotic bacteria. PMID:25064650

Gandhi, Akanksha; Cui, Yuxiang; Zhou, Mingyang; Shah, Nagendra P

2014-10-01

383

Short communication: The effect of water temperature on the viability of silage inoculants.  

PubMed

The objective of this study was to determine if exposure to high temperatures in water affects the viability of various silage inoculants. Inoculants were enumerated on De Man, Rogosa, Sharpe agar to standardize a final count (colony-forming units) in water such that about 500 mL added to 1 tonne of wet forage would achieve a recommended application rate of about 100,000 cfu of lactic acid bacteria (LAB) per gram of wet forage. Testing was done in 4 sequences (SEQ). For each SEQ, inoculants were mixed in deionized water for 45 min at 30 degrees C followed by incubation for 6 h at 30 degrees C (SEQ 1), 35 degrees C (SEQ 2), 40 degrees C (SEQ 3), or 45 degrees C (SEQ 4) in duplicate 125-mL flasks rotating at 125 rpm. After 6 h, rotation was stopped and the temperature was lowered to 30 degrees C for the next 18 h for all SEQ. Numbers of LAB were enumerated at 0, 3, 6, and 24 h. Each sequence was repeated twice. Incubation at a moderate temperature (SEQ 1) did not affect the viability of the microbial inoculants. The viability of the inoculants declined with increasing temperature (SEQ 2 to 4) but the effect varied by inoculant. For some inoculants exposure to 35 degrees C resulted in substantial decreases in viable cells (loss of 0.5 to 1 log cfu/mL). Incubation at higher temperatures resulted in even greater losses in viability for some inoculants. Losses of more than 0.5 log cfu/mL would most likely make the application of these inoculants ineffective in the field. Lactobacillus plantarum MTD/1 was the most thermotolerant organism tested, because it was unaffected by all temperatures (30 to 45 degrees C) after 3 h of incubation. Lactobacillus plantarum MTD/1 and Lactobacillus buchneri 40788 also appeared to have better thermotolerance as their numbers substantially increased between 6 and 24 h in SEQ 4. These data show that some silage inoculants are more thermotolerant than others and that precautions should be taken to ensure that microbial inoculants that are applied to forage do not reach elevated temperatures during use. PMID:18096945

Mulrooney, C N; Kung, L

2008-01-01

384

Economic analysis  

SciTech Connect

The Energy Policy and Conservation Act (EPCA) mandated that minimum energy efficiency standards be established for classes of refrigerators and refrigerator-freezers, freezers, clothes dryers, water heaters, room air conditioners, home heating equipment, kitchen ranges and ovens, central air conditioners, and furnaces. EPCA requires that standards be designed to achieve the maximum improvement in energy efficiency that is technologically feasible and economically justified. Following the introductory chapter, Chapter Two describes the methodology used in the economic analysis and its relationship to legislative criteria for consumer product efficiency assessment; details how the CPES Value Model systematically compared and evaluated the economic impacts of regulation on the consumer, manufacturer and Nation. Chapter Three briefly displays the results of the analysis and lists the proposed performance standards by product class. Chapter Four describes the reasons for developing a baseline forecast, characterizes the baseline scenario from which regulatory impacts were calculated and summarizes the primary models, data sources and assumptions used in the baseline formulations. Chapter Five summarizes the methodology used to calculate regulatory impacts; describes the impacts of energy performance standards relative to the baseline discussed in Chapter Four. Also discussed are regional standards and other program alternatives to performance standards. Chapter Six describes the procedure for balancing consumer, manufacturer, and national impacts to select standard levels. Details of models and data bases used in the analysis are included in Appendices A through K.

None

1980-06-01

385

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

386

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

387

NATURAL RESOURCE ABUNDANCE AND ECONOMIC GROWTH REVISITED  

Microsoft Academic Search

Data on energy and mineral reserves suggest that natural resource abundance has not been a significant structural determinant of economic growth between 1970 and 1989. The story behind the effect of natural resources on economic growth is a complex one that typical growth regressions do not capture well. Preliminary evidence suggests that natural resources may affect economic growth through both

Jean-Philippe C. Stijns

2001-01-01

388

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.

389

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. PMID:21605929

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

2011-01-01

390

Effect of selenate on viability and selenomethionine accumulation of Chlorella sorokiniana grown in batch culture.  

PubMed

The aim of this work was to study the effect of Se(+VI) on viability, cell morphology, and selenomethionine accumulation of the green alga Chlorella sorokiniana grown in batch cultures. Culture exposed to sublethal Se concentrations of 40 mg · L(-1) (212 ?M) decreased growth rates for about 25% compared to control. A selenate EC50 value of 45 mg · L(-1) (238.2 ?M) was determined. Results showed that chlorophyll and carotenoids contents were not affected by Se exposure, while oxygen evolution decreased by half. Ultrastructural studies revealed granular stroma, fingerprint-like appearance of thylakoids which did not compromise cell activity. Unlike control cultures, SDS PAGE electrophoresis of crude extracts from selenate-exposed cell cultures revealed appearance of a protein band identified as 53 kDa Rubisco large subunit of Chlorella sorokiniana, suggesting that selenate affects expression of the corresponding chloroplast gene as this subunit is encoded in the chloroplast DNA. Results revealed that the microalga was able to accumulate up to 140 mg · kg(-1) of SeMet in 120 h of cultivation. This paper shows that Chlorella sorokiniana biomass can be enriched in the high value aminoacid SeMet in batch cultures, while keeping photochemical viability and carbon dioxide fixation activity intact, if exposed to suitable sublethal concentrations of Se. PMID:24688385

Gojkovic, Živan; Vílchez, Carlos; Torronteras, Rafael; Vigara, Javier; Gómez-Jacinto, Veronica; Janzer, Nora; Gómez-Ariza, José-Luis; Márová, Ivana; Garbayo, Ines

2014-01-01

391

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

PubMed

Air pollution is frequently proposed as a cause of the increased incidence of allergy in industrialised countries. We investigated the impact of ozone (O(3)) on reactive oxygen species (ROS) and allergen content of ragweed pollen (Ambrosia artemisiifolia). Pollen was exposed to acute O(3) 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 O(3) 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 O(3), determined from the mRNA levels of the major allergens. We conclude that O(3) can increase ragweed pollen allergenicity through stimulation of ROS-generating NAD(P)H oxidase. PMID:21605929

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

2011-10-01

392

Fat Graft Viability in the Subcutaneous Plane versus the Local Fat Pad  

PubMed Central

Background: Fat grafting has been increasingly utilized in both aesthetic and reconstructive surgical procedures, yet the basic scientific understanding of fat grafting has lagged behind the pace of clinical innovation and utilization. This lack of basic scientific understanding has perhaps manifested itself in the wide range of graft viability reported across the literature. This study attempts to further the underlying mechanisms of fat graft take and viability through the comparison of the subcutaneous plane and the local fat pad in athymic rats. Methods: Lipoaspirate from a consenting patient was grafted into 2 locations in the subcutaneous plane and into the 2 inguinal fat pads in each of 4 athymic rats. Specimens were then collected after 47 days, and immunohistochemistry was utilized to determine angiogenesis in the fat grafts as a measure of fat graft take. Data were analyzed using the Student’s t test and analysis of variance followed by multiple comparisons. Results: There was no statistically significant difference (P = 0.2913) between the inguinal fat pad and the subcutaneous plane when measuring neovascularization. Analysis of variance comparing the graft locations also indicated no statistically significant difference when comparing each of the rats. Conclusions: Investigation into fat graft injection location indicates that there is no statistically significant difference in angiogenesis signals between the subcutaneous plane and the local fat pad in the athymic rat model. Further research should aim to continue to close the gap between clinical practice and basic scientific understanding of fat grafting. PMID:25587494

Constantine, Ryan S.; Harrison, Bridget; Davis, Kathryn E.

2014-01-01

393

Effect of Selenate on Viability and Selenomethionine Accumulation of Chlorella sorokiniana Grown in Batch Culture  

PubMed Central

The aim of this work was to study the effect of Se(+VI) on viability, cell morphology, and selenomethionine accumulation of the green alga Chlorella sorokiniana grown in batch cultures. Culture exposed to sublethal Se concentrations of 40 mg·L?1 (212??M) decreased growth rates for about 25% compared to control. A selenate EC50 value of 45?mg·L?1 (238.2??M) was determined. Results showed that chlorophyll and carotenoids contents were not affected by Se exposure, while oxygen evolution decreased by half. Ultrastructural studies revealed granular stroma, fingerprint-like appearance of thylakoids which did not compromise cell activity. Unlike control cultures, SDS PAGE electrophoresis of crude extracts from selenate-exposed cell cultures revealed appearance of a protein band identified as 53?kDa Rubisco large subunit of Chlorella sorokiniana, suggesting that selenate affects expression of the corresponding chloroplast gene as this subunit is encoded in the chloroplast DNA. Results revealed that the microalga was able to accumulate up to 140?mg·kg?1 of SeMet in 120?h of cultivation. This paper shows that Chlorella sorokiniana biomass can be enriched in the high value aminoacid SeMet in batch cultures, while keeping photochemical viability and carbon dioxide fixation activity intact, if exposed to suitable sublethal concentrations of Se. PMID:24688385

Vílchez, Carlos; Torronteras, Rafael; Vigara, Javier; Gómez-Jacinto, Veronica; Janzer, Nora; Gómez-Ariza, José-Luis; Márová, Ivana

2014-01-01

394

Egg viability in urinary schistosomiasis. I. New methods compared with available methods.  

PubMed

A new method of quantifying viability and hatchability of Schistosoma haematobium eggs in urine has been developed. It consists of filtering urine samples through Nytrel filters followed by mercurochrome staining to assist in the detection of viable (motile) miracidia in egg shells, and iodine staining to show hatched miracidia. The new method is compared with two existing techniques for viability/hatchability determination, centrifugation hatching and Nuclepore filtration trypan blue staining. Seventy-three egg positive urine samples are compared; the overall proportions of viable eggs are very close for centrifugation hatching and the new method, but 33% of eggs are lost in centrifugation and 19% of eggs are unclassifiable by Nuclepore filtration trypan blue staining. The main advantages and disadvantages of the new and existing methods are described and discussed; the cheapness, simplicity and ease of performance of the new method make it suitable for large-scale field use. Suggestions for improvements and standardization of the new method are made. PMID:7679149

Braun-Munzinger, R A; Southgate, B A

1993-02-01

395

Effects of Birds Ingesting Heterodera rostochiensis Cysts on Viability of Eggs and Larvae  

PubMed Central

Rate of passage through the digestive systems and effects of ingestion on viability of contents of cysts of Heterodera rostochiensis were determined in feeding trials with pigeons, thrushes, starlings, cowbirds, sparrows, and quails. Depending upon species of birds, 12-82% of the cysts ingested passed through the digestive system within 0.5 h. Pigeons required 6 h for complete evacuation. All other birds cmnpletely evacuated ingested cysts from their digestive systems within 3 h. Contents of cysts were nonviable if they were retained in the digestive system of starlings for more than 1.5 h, pigeons more than 1 h, or other birds more than 0.5 h. Cyst contents were nonviable if they remained in contact with excreta from cowbirds or quails for 4 h, thrushes for 96 h, or other species for 72 h after passage. Viability of contents of cysts was inversely related to exposure to excreta-filtrate concentration. Larvae failed to emerge from cysts that were exposed to a 25% concentration of excreta filtrate from starlings, 50% concentration from pigeons or thrushes, or 100% concentration of excreta filtrates from each of the other species. Cysts that were subjected to 44 C (avg. body temperature of cowbirds) for more than 3.5 h were nonviable. Cysts that passed through birds and collected with excrement on polyethylene or soil produced no infective larvae on potato. PMID:19308240

Brodie, B. B.

1976-01-01

396

Impacts of viability and purification on the specific gravity of Cryptosporidium oocysts.  

PubMed

The specific gravity of unpurified and purified Cryptosporidium oocysts was measured using an isopycnic gradient centrifugation technique. Specific gravity varied depending on the viability of the oocysts, as defined by permeabilty to 4',6-diamidino-2-phenylindole (DAPI) and propidium iodide (PI), the presence or absence of internal structures, and whether or not oocysts were purified. The modal range of densities for a population of 1.4-week-old unpurified oocysts, was 1070-1073 kg/m3. This range was higher than that determined for 14-week-old purified oocysts, 1067-1070 kg/m3. Eleven- and 12-week-old unpurified populations exhibited a bimodal distribution of densities, with densities most frequently in the 1005-1041 and in the 1077-1108 kg/m3 range. In these populations, a high percentage of the oocysts having densities greater than 1077 kg/m3 were viable, while oocysts in the 1005-1024 kg/m3 range were predominately nonintact, and oocysts in the 1024-1041 kg/m3 range were intact, but permeable to DAPI and PI (nonviable). This work demonstrates the importance of controlling factors that may impact the viability of oocysts when conducting studies that examine the transport of these microorganisms in the environment and through water treatment processes. PMID:16054671

Young, Pamela L; Komisar, Simeon J

2005-09-01

397

The Cytotoxic Role of Intermittent High Glucose on Apoptosis and Cell Viability in Pancreatic Beta Cells  

PubMed Central

Objectives. Glucose fluctuations are both strong predictor of diabetic complications and crucial factor for beta cell damages. Here we investigated the effect of intermittent high glucose (IHG) on both cell apoptosis and proliferation activity in INS-1 cells and the potential mechanisms. Methods. Cells were treated with normal glucose (5.5?mmol/L), constant high glucose (CHG) (25?mmol/L), and IHG (rotation per 24?h in 11.1 or 25?mmol/L) for 7 days. Reactive oxygen species (ROS), xanthine oxidase (XOD) level, apoptosis, cell viability, cell cycle, and expression of cyclinD1, p21, p27, and Skp2 were determined. Results. We found that IHG induced more significant apoptosis than CHG and normal glucose; intracellular ROS and XOD levels were more markedly increased in cells exposed to IHG. Cells treated with IHG showed significant decreased cell viability and increased cell proportion in G0/G1 phase. Cell cycle related proteins such as cyclinD1 and Skp2 were decreased significantly, but expressions of p27 and p21 were increased markedly. Conclusions. This study suggested that IHG plays a more toxic effect including both apoptosis-inducing and antiproliferative effects on INS-1 cells. Excessive activation of cellular stress and regulation of cyclins might be potential mechanism of impairment in INS-1 cells induced by IHG. PMID:24772447

Zhang, Zhen; Li, Jing; Yang, Lei; Chen, Rongping; Yang, Rui; Zhang, Hua; Cai, Dehong; Chen, Hong

2014-01-01

398

Quercetin both partially attenuates hydrogen peroxide-induced toxicity and decreases viability of rat glial cells.  

PubMed

Quercetin is one of the most ubiquitous flavonoids in foods of plant origin. Although quercetin is generally considered to provide protection against oxidative injury, recent studies have shown to be cytotoxic to many cell types. We intended here to determine whether quercetin protects against H2O2-induced toxicity and/or affects viability of rat mixed glial cells. The cells were obtained from 1-3 day olds rat brains and incubated in a humidified atmosphere of 5% CO2, at 37 °C in flasks. In the quercetin groups, different quercetin concentrations (1, 10, 50, 75 or 100 ?M) were applied alone for 24 h. For H2O2 cytotoxicity group, the glial cells were treated for 3 h with 100 ?M H2O2 which induced 75% cell death. In another group, the cells were treated with 100 ?M H2O2 plus respective quercetin concentrations simultaneously for 3 h, the medium was removed and refed for 24 h. MTT test was then applied and statistical significance was ascertained by one way analysis of variance, followed by Tukey's multiple comparison test. Quercetin starting from 50 ?M decreased the glia survival significantly. In H2O2 plus quercetin co-treated groups, both 75 and 100 ?M quercetin attenuated toxic effect of H2O2 by 15%. In conclusion, quercetin both partially protects H2O2-induced gliotoxicity and decreases rat glial cell viability in primary culture. PMID:21840824

Kabadere, Selda; Oztopcu-Vatan, Pinar; Uyar, R; Durmaz, R

2011-09-01

399

Heterodera glycines Infectivity and Egg Viability Following Nonhost Crops and During Overwintering.  

PubMed

The most effective management program for soybean cyst nematode, Heterodera glycines, is a crop rotation that uses nonhost crops and resistant soybean cultivars. However, little is known about the effects of rotation crops and overwintering on H. glycines biology. These experiments were initiated to determine the effects of seven alternative crops on H. glycines' ability to infect and mature on subsequent soybean crops, and to assess the viability of eggs during the overwintering months. Rotation studies were conducted for 2 years in each of two naturally infested fields, and overwintering tests were conducted in three consecutive growing seasons in one naturally infested field. Rotation crop and fallow treatments did not have a consistent effect on the ability of H. glycines to infect soybean or mature. Soybean yields were often higher following fallow or a nonhost crop than following soybean, although not usually significantly so. Heterodera glycines egg viability did not differ (P < 0.05) between overwintering months at 0-to-10 or 10-to-20-cm soil depths. These results suggest that H. glycines' ability to infect a subsequent soybean crop and develop to maturity is not diminished by nonhost crops or during the winter months. PMID:19262870

Jackson, T A; Smith, G S; Niblack, T L

2005-09-01

400

Effects of borate-based bioactive glass on neuron viability and neurite extension.  

PubMed

Bioactive glasses have recently been shown to promote regeneration of soft tissues by positively influencing tissue remodeling during wound healing. We were interested to determine whether bioactive glasses have the potential for use in the treatment of peripheral nerve injury. In these experiments, degradable bioactive borate glass was fabricated into rods and microfibers. To study the compatibility with neurons, embryonic chick dorsal root ganglia (DRG) were cultured with different forms of bioactive borate glass. Cell viability was measured with no media exchange (static condition) or routine media exchange (transient condition). Neurite extension was measured within fibrin scaffolds with embedded glass microfibers or aligned rod sheets. Mixed cultures of neurons, glia, and fibroblasts growing in static conditions with glass rods and microfibers resulted in decreased cell viability. However, the percentage of neurons compared with all cell types increased by the end of the culture protocol compared with culture without glass. Furthermore, bioactive glass and fibrin composite scaffolds promoted neurite extension similar to that of control fibrin scaffolds, suggesting that glass does not have a significant detrimental effect on neuronal health. Aligned glass scaffolds guided neurite extension in an oriented manner. Together these findings suggest that bioactive glass can provide alignment to support directed axon growth. PMID:24027222

Marquardt, Laura M; Day, Delbert; Sakiyama-Elbert, Shelly E; Harkins, Amy B

2014-08-01

401

Economic impact of stimulated technological activity. Part 1: Overall economic impact of technological progress: Its measurement  

NASA Technical Reports Server (NTRS)

Investigations were performed at the national economic level to explore the aggregate effects of technological progress on economic growth. Inadequacies in existing marco-economic yardsticks forced the study to focus on the cost savings effects achieved through technological progress. The central questions discussed in this report cover: (1) role of technological progress in economic growth, (2) factors determining the rate of economic growth due to technological progress; (3) quantitative measurements of relationships between technological progress, its determinants, and subsequent economic growth; and (4) effects of research and development activities of the space program. For Part 2, see N72-32174.

1971-01-01

402

Kentucky Annual Economic Report  

E-print Network

; transportation economics; health economics; regulatory reform; public finance; technology use and adoption-term economic, education, health, environmental, energy, community, public finance, and demographic factors

Hayes, Jane E.

403

Kentucky Annual Economic Report  

E-print Network

economics; health economics; regulatory reform; public finance; and economic growth and development, health, environmental, energy, community, public finance, and demographic factors affecting Kentucky

Hayes, Jane E.

404

Basic Economic Principles  

NASA Technical Reports Server (NTRS)

An economic approach to design efficient transportation systems involves maximizing an objective function that reflects both goals and costs. A demand curve can be derived by finding the quantities of a good that solve the maximization problem as one varies the price of that commodity, holding income and the prices of all other goods constant. A supply curve is derived by applying the idea of profit maximization of firms. The production function determines the relationship between input and output.

Tideman, T. N.

1972-01-01

405

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

406

Factors influencing the growth and viability of Actinobacillus actinomycetemcomitans.  

PubMed

The metabolic requirements for the routine growth of Actinobacillus actinomycetemcomitans were investigated by the addition of nutrients to conventional bacteriological and tissue culture media. Commonly used tissue culture media required fetal bovine serum as an additive to sustain bacterial growth rates comparable to those obtained with bacteriological media. The addition of increasing concentrations of yeast extract to bacteriological medium increased the growth rate of several A. actinomycetemcomitans strains. In an attempt to identify the components of yeast extract that enhanced the growth of A. actinomycetemcomitans, a number of vitamins, essential and non-essential amino acids were tested for their role in promoting growth. The addition of L-cystine resulted in bacterial growth rates comparable to those with yeast extract. Thiamine increased the growth of several A. actinomycetemcomitans strains but did not result in growth rates comparable to those with yeast extract. The addition of physiological concentrations of steroid hormones to bacteriological medium enhanced the growth of A. actinomycetemcomitans. Additional iron compounds and fat-soluble vitamins had no influence on A. actinomycetemcomitans growth. However, the requirement of iron for bacterial growth remains unclear. The optimal pH range for growth of A. actinomycetemcomitans was between pH 7.0-8.0 in a medium containing 0.5-1% NaCl. Several interesting observations on the viability of A. actinomycetemcomitans were made. A rapid reduction of A. actinomycetemcomitans viability occurred following suspension in distilled water. The presence of the detergent Triton X-100 at concentrations above 2% (v/v) also decreased the viability of A. actinomycetemcomitans within 10 min. PMID:8152837

Sreenivasan, P K; Meyer, D H; Fives-Taylor, P M

1993-12-01

407

Left Ventricular Remodeling after Late Revascularization Correlates with Baseline Viability  

PubMed Central

The ideal management of stable patients who present late after acute ST-elevation myocardial infarction (STEMI) is still a matter of conjecture. We hypothesized that the extent of improvement in left ventricular function after successful revascularization in this subset was related to the magnitude of viability in the infarct-related artery territory. However, few studies correlate the improvement of left ventricular function with the magnitude of residual viability in patients who undergo percutaneous coronary intervention in this setting. In 68 patients who presented later than 24 hours after a confirmed first STEMI, we performed resting, nitroglycerin-enhanced, technetium-99m sestamibi single-photon emission computed tomography–myocardial perfusion imaging (SPECT–MPI) before percutaneous coronary intervention, and again 6 months afterwards. Patients whose baseline viable myocardium in the infarct-related artery territory was more than 50%, 20% to 50%, and less than 20% were divided into Groups 1, 2, and 3 (mildly, moderately, and severely reduced viability, respectively). At follow-up, there was significant improvement in end-diastolic volume, end-systolic volume, and left ventricular ejection fraction in Groups 1 and 2, but not in Group 3. We conclude that even late revascularization of the infarct-related artery yields significant improvement in left ventricular remodeling. In patients with more than 20% viable myocardium in the infarct-related artery territory, the extent of improvement in left ventricular function depends upon the amount of viable myocardium present. The SPECT–MPI can be used as a guide for choosing patients for revascularization. PMID:25120390

Goel, Pravin K.; Kapoor, Aditya; Gambhir, Sanjay; Pradhan, Prasanta K.; Barai, Sukanta; Tewari, Satyendra; Garg, Naveen; Kumar, Sudeep; Jain, Suruchi; Madhusudan, Ponnusamy; Murthy, Siddegowda

2014-01-01

408

Integrating genetic data and population viability analyses for the identification of harbour seal (Phoca vitulina) populations and management units.  

PubMed

Identification of populations and management units is an essential step in the study of natural systems. Still, there is limited consensus regarding how to define populations and management units, and whether genetic methods allow for inference at the relevant spatial and temporal scale. Here, we present a novel approach, integrating genetic, life history and demographic data to identify populations and management units in southern Scandinavian harbour seals. First, 15 microsatellite markers and model- and distance-based genetic clustering methods were used to determine the population genetic structure in harbour seals. Second, we used harbour seal demographic and life history data to conduct population viability analyses (PVAs) in the vortex simulation model in order to determine whether the inferred genetic units could be classified as management units according to Lowe and Allendorf's (Molecular Ecology, 19, 2010, 3038) 'population viability criterion' for demographic independence. The genetic analyses revealed fine-scale population structuring in southern Scandinavian harbour seals and pointed to the existence of several genetic units. The PVAs indicated that the census population size of each of these genetic units was sufficiently large for long-term population viability, and hence that the units could be classified as demographically independent management units. Our study suggests that population genetic inference can offer the same degree of temporal and spatial resolution as 'nongenetic' methods and that the combined use of genetic data and PVAs constitutes a promising approach for delineating populations and management units. PMID:24382213

Olsen, Morten T; Andersen, Liselotte W; Dietz, Rune; Teilmann, Jonas; Härkönen, Tero; Siegismund, Hans R

2014-02-01

409

Assessment of Cell Viability in Intact Glandular Tissue in Chironomus ramosus using Dye-exclusion and Colorimetric Assays.  

PubMed

Conventionally, dye-exclusion test for determining cell viability has been restricted only for cells in suspension in tissue culture. In this paper, salivary gland of Chironomus has been proposed as a simple tissue model system where dye-exclusion test can be reliably employed for the intact gland. We have compared suitability of commonly used vital dyes and nigrosin was found suitable for the salivary gland cells. Biochemical tests using tetrazolium salts are also commonly used for determining quantitative indices of cell viability in metabolically active cells. Ours is the first attempt to extend the same technique for the whole tissue. We standardized the conditions and prepared a protocol for MTT-based colorimetric assay suitable for the salivary gland of Chironomus. A strong correlation (r(2) = 0.9893) was obtained where increasing O.D. correlated linearly with the number of live glands. We concluded that nigrosin dye-exclusion and MTT metabolic inclusion assays are suitable methods for the viability test of metabolically active intact salivary gland of Chironomus which can serve as a potential model for the assessment of cytotoxicity in future. PMID:19003063

Nath, B B; Babrekar, A A; Parthasarathy, B

2005-09-01

410

HaCaT Keratinocytes Response on Antimicrobial Atelocollagen Substrates: Extent of Cytotoxicity, Cell Viability and Proliferation.  

PubMed

The effective and widely tested biocides: Benzalkonium chloride, bronopol, chitosan, chlorhexidine and irgasan were added in different concentrations to atelocollagen matrices. In order to assess how these antibacterial agents influence keratinocytes cell growth, cell viability and proliferation were determined by using MTT assay. Acquired data indicated a low toxicity by employing any of these chemical substances. Furthermore, cell viability and proliferation were comparatively similar to the samples where there were no biocides. It means that regardless of the agent, collagen-cell-attachment properties are not drastically affected by the incorporation of those biocides into the substrate. Therefore, these findings suggest that these atelocollagen substrates enhanced by the addition of one or more of these agents may render effectiveness against bacterial stains and biofilm formation, being the samples referred to herein as "antimicrobial substrates" a promising view in the design of novel antimicrobial biomaterials potentially suitable for tissue engineering applications. PMID:24956439

López-García, Jorge; Lehocký, Marián; Humpolí?ek, Petr; Sáha, Petr

2014-01-01

411

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

412

Applied studies on the viability of El Tor vibrios*  

PubMed Central

The viability of El Tor vibrios was tested at various temperatures in foodstuffs, kitchen utensils, and water after these materials had been directly contaminated with stools of cholera patients or carriers from the Philippines, collected in 1963-64. The period of survival of vibrios in foodstuffs was 2-5 days at room temperature (30°C-32°C) and as long as 9 days under refrigeration (5°C-10°C). Vibrios survived even longer in refrigerated water. The period of survival was shorter for all materials contaminated with carriers' stools, which contain fewer vibrios. Chlorinated lime was more effective than potassium permanganate as a decontaminant. PMID:4870081

Pesigan, T. P.; Plantilla, J.; Rolda, M.

1967-01-01

413

Tissue viability nurses' experiences of managing wound exudate.  

PubMed

Wound exudate presents several challenges for patients and nurses. The description of exudate volume, colour and viscosity varies greatly, often depending on the personal preference of the nurse. When the nature and volume of exudate has been described, management of exudate presents its own issues in terms of ensuring that the appropriate dressing or intervention is selected and used effectively. This article reports on the outcomes of a series of discussion groups held to explore the difficulties tissue viability nurse specialists experience in relation to advising non-specialist nurses about wound exudate in the practice setting. PMID:25335633

Glover, Deborah

2014-10-28

414

Effect of aerosolization on culturability and viability of gram-negative bacteria.  

PubMed Central

Estimations of the bacterial content of air can be more easily made now than a decade ago, with colony formation the method of choice for enumeration of airborne bacteria. However, plate counts are subject to error because bacteria exposed to the air may remain viable yet lose the ability to form colonies, i.e., they become viable but nonculturable. If airborne bacteria exhibit this phenomenon, colony formation data will significantly underestimate the bacterial populations in air samples. The objective of the study reported here was to determine the effect of aerosolization on viability and colony-forming ability of Serratia marcescens, Klebsiella planticola, and Cytophaga allerginae. A collision nebulizer was used to spray bacterial suspensions into an aerosol chamber, after which duplicate samples were collected in all-glass impingers over a 4-h period. Humidity was maintained at ca. 20 to 25%, and temperature was maintained at 20 to 22 degrees C for each of two replicate trials per microorganism. Viability was determined by using a modified direct viable count method, employing nalidixic acid or aztreonam and p-iodonitrotetrazolium violet (INT). Cells were stained with acridine orange and observed by epifluorescence microscopy to enumerate total and viable cells. Viable cells were defined as those elongating in the presence of antibiotic and/or reducing INT. CFU were determined by plating on tryptic soy agar and R2A agar. It was found that culture techniques did not provide an adequate description of the bacterial burdens of indoor air (i.e., less than 10% of the aerosolized bacteria were capable of forming visible colonies). It is concluded that total cell count procedures provide a better approximation of the number of bacterial cells in air and that procedures other than plate counting are needed to enumerate bacteria in aerosol samples, especially if the public health quality of indoor air is to be estimated. PMID:9293010

Heidelberg, J F; Shahamat, M; Levin, M; Rahman, I; Stelma, G; Grim, C; Colwell, R R

1997-01-01

415

or rain, affect pollen viability and ultimate pollinationUSE OF DIGITAL IMAGE ANALYSIS, of their crops. Therefore simple, inexpensive techniques  

E-print Network

TO ESTIMATE of interest to breeders and growers alike. CONVENTIONAL AND GLYPHOSATE- Numerous methods are used were compared to determine differences in anatomical development, or any combination of these viability glyphosate-resistant (GR) and glyphosate-treated GR cotton (Gos- germination solution on a slide containing

Kalisz, Susan

416

Viability of Construct Validity of the Speaking Modules of International Language Examinations (IELTS vs. TOEFL iBT): Evidence from Iranian Test-Takers  

ERIC Educational Resources Information Center

The aim of the present research is to examine the viability of the construct validity of the speaking modules of two internationally recognized language proficiency examinations, namely IELTS and TOEFL iBT. High-stake standardized tests play a crucial and decisive role in determining the future academic life of many people. Overall obtained scores…

Zahedi, Keivan; Shamsaee, Saeedeh

2012-01-01

417

On economic bicameralism  

E-print Network

(cont.) for both economic profitability and democratic justice, is explored after the roots of the idea of economic bicameralism in socio-economic history and existing socio-economic institutions (such as Works Councils) ...

Ferreras, Isabelle, 1975-

2004-01-01

418

Economic evaluation and cost-effectiveness thresholds: signals to firms and implications for R & D investment and innovation.  

PubMed

In this article we describe how reimbursement cost-effectiveness thresholds, per unit of health benefit, whether set explicitly or observed implicitly via historical reimbursement decisions, serve as a signal to firms about the commercial viability of their R&D projects (including candidate products for in-licensing). Traditional finance methods for R&D project valuations, such as net present value analyses (NPV), incorporate information from these payer reimbursement signals to help determine which R&D projects should be continued and which should be terminated (in the case of the latter because they yield an NPV < 0). Because the influence these signals have for firm R&D investment decisions is so significant, we argue that it is important for reimbursement thresholds to reflect the economic value of the unit of health benefit being considered for reimbursement. Thresholds set too low (below the economic value of the health benefit) will result in R&D investment levels that are too low relative to the economic value of R&D (on the margin). Similarly, thresholds set too high (above the economic value of the health benefit) will result in inefficiently high levels of R&D spending. The US in particular, which represents approximately half of the global pharmaceutical market (based on sales), and which seems poised to begin undertaking cost effectiveness in a systematic way, needs to exert caution in setting policies that explicitly or implicitly establish cost-effectiveness reimbursement thresholds for healthcare products and technologies, such as pharmaceuticals. PMID:19803536

Vernon, John A; Goldberg, Robert; Golec, Joseph

2009-01-01

419

The postmitotic Saccharomyces cerevisiae after spaceflight showed higher viability  

NASA Astrophysics Data System (ADS)

The budding yeast Saccharomyces cerevisiae has been proposed as an ideal model organism for clarifying the biological effects caused by spaceflight conditions. The postmitotic S. cerevisiae cells onboard Practice eight recoverable satellite were subjected to spaceflight for 15 days. After recovery, the viability, the glycogen content, the activities of carbohydrate metabolism enzymes, the DNA content and the lipid peroxidation level in yeast cells were analyzed. The viability of the postmitotic yeast cells after spaceflight showed a three-fold increase as compared with that of the ground control cells. Compared to the ground control cells, the lipid peroxidation level in the spaceflight yeast cells markedly decreased. The spaceflight yeast cells also showed an increase in G2/M cell population and a decrease in Sub-G1 cell population. The glycogen content and the activities of hexokinase and succinate dehydrogenase significantly decreased in the yeast cells after spaceflight. In contrast, the activity of malate dehydrogenase showed an obvious increase after spaceflight. These results suggested that microgravity or spaceflight could promote the survival of postmitotic S. cerevisiae cells through regulating carbohydrate metabolism, ROS level and cell cycle progression.

Yi, Zong-Chun; Li, Xiao-Fei; Wang, Yan; Wang, Jie; Sun, Yan; Zhuang, Feng-Yuan

2011-06-01

420

Proteus mirabilis viability after lithotripsy of struvite calculi  

NASA Astrophysics Data System (ADS)

Urinary calculi composed of struvite harbor urease-producing bacteria within the stone. The photothermal mechanism of holmium:YAG lithotripsy is uniquely different than other lithotripsy devices. We postulated that bacterial viability of struvite calculi would be less for calculi fragmented with holmium:YAG irradiation compared to other lithotripsy devices. Human calculi of known struvite composition (greater than 90% magnesium ammonium phosphate hexahydrate) were incubated with Proteus mirabilis. Calculi were fragmented with no lithotripsy (controls), or shock wave, intracorporeal ultrasonic, electrohydraulic, pneumatic, holmium:YAG or pulsed dye laser lithotripsy. After lithotripsy, stone fragments were sonicated and specimens were serially plated for 48 hours at 38 C. Bacterial counts and the rate of bacterial sterilization were compared. Median bacterial counts (colony forming units per ml) were 8 X 106 in controls and 3 X 106 in shock wave, 3 X 107 in ultrasonic, 4 X 105 in electrohydraulic, 8 X 106 in pneumatic, 5 X 104 in holmium:YAG and 1 X 106 in pulsed dye laser lithotripsy, p less than 0.001. The rate of bacterial sterilization was 50% for holmium:YAG lithotripsy treated stones versus 0% for each of the other cohorts, p less than 0.01. P. mirabilis viability is less after holmium:YAG irradiation compared to other lithotripsy devices.

Prabakharan, Sabitha; Teichman, Joel M. H.; Spore, Scott S.; Sabanegh, Edmund; Glickman, Randolph D.; McLean, Robert J. C.

2000-05-01

421

Assessment of activated sludge viability with flow cytometry.  

PubMed

The aim of the study was to evaluate the applicability of fluorescent dyes and multiparameter flow cytometry for the rapid and direct viability/activity assessment of activated sludge samples taken from wastewater treatment plants. Viability and activity of the biomass were estimated respectively through cellular membrane integrity, staining with SYBR Green I and Propidium Iodide, and through fluorogenic dyes capable of detecting enzymatic activity, as FDA and BCECF-AM. A procedure has been developed to disaggregate sludge flocs before dyes staining and cytometric analysis. The developed procedure allows a high recovery of bacteria with good accuracy and repeatability, and minimize the damage of the cells suspension obtained from the disaggregation of the flocs. These measurements were applied to estimate the two main parameters required to define the biological activated sludge process: the endogenous decay rate and the specific growth rate in exponential phase with high F/M ratio. Oxygen utilization rate measurements (OUR) were conducted to conventionally monitor the activity of the biomass. The preliminary data are encouraging and support the possibility to investigate bacteria dynamics on wastewater treatment plants. PMID:11827352

Ziglio, Giuliano; Andreottola, Gianni; Barbesti, Silvia; Boschetti, Giorgio; Bruni, Laura; Foladori, Paola; Villa, Roberta

2002-01-01

422

Noninvasive assessment myocardial viability: current status and future directions.  

PubMed

Observations of reversibility of cardiac contractile dysfunction in patients with coronary artery disease and ischemia were first made more than 40 years ago. Since that time a wealth of basic science and clinical data has been gathered exploring the mechanisms of this phenomenon of myocardial viability and relevance to clinical care of patients. Advances in cardiac imaging techniques have contributed greatly to knowledge in the area, first with thallium-201 imaging, then later with Tc-99m-based tracers for SPECT imaging and metabolic tracers used in conjunction with positron emission tomography (PET), most commonly F-18 FDG in conjunction with blood flow imaging with N-13 ammonia or Rb-82 Cl. In parallel, stress echocardiography has made great progress also. Over time observational studies in patients using these techniques accumulated and were later summarized in several meta-analyses. More recently, cardiac magnetic resonance imaging (CMR) has contributed further information in combination with either late gadolinium enhancement imaging or dobutamine stress. This review discusses the tracer and CMR imaging techniques, the pooled observational data, the results of clinical trials, and ongoing investigation in the field. It also examines some of the current challenges and issues for researchers and explores the emerging potential of combined PET/CMR imaging for myocardial viability. PMID:23771636

Allman, Kevin C

2013-08-01

423

Effect of various commercial buffers on sperm viability and capacitation.  

PubMed

A wide variety of sperm preparation protocols are currently available for assisted conception. They include density gradient separation and washing methods. Both aim at isolating and capacitating as much motile sperm as possible for subsequent oocyte fertilization. The aim of this study was to examine the effects of four commercial sperm washing buffers on sperm viability and capacitation. Semen samples from 48 healthy donors (normal values of sperm count, motility, morphology, and volume) were analyzed. After separation (density gradient 40/80%), sperm were incubated in various buffers then analysed for reactive oxygen species (ROS) production, viability, tyrosine phosphorylation (Tyr-P), cholera toxin B subunit (CTB) labeling, and the acrosome reaction (AR). The buffers affected ROS generation in various ways resulting either in rapid cell degeneration (when the amount of ROS was too high for cell survival) or the inability of the cells to maintain correct functioning (when ROS were too few). Only when the correct ROS generation curve was maintained, suitable membrane reorganization, evidenced by CTB labeling was achieved, leading to the highest percentages of both Tyr-P- and acrosome-reacted-cells. Distinguishing each particular pathological state of the sperm sample would be helpful to select the preferred buffer treatment since both ROS production and membrane reorganization can be significantly altered by commercial buffers. PMID:24673547

Andrisani, Alessandra; Donŕ, Gabriella; Ambrosini, Guido; Bonanni, Guglielmo; Bragadin, Marcantonio; Cosmi, Erich; Clari, Giulio; Armanini, Decio; Bordin, Luciana

2014-08-01

424

Bacterial abundance and viability in long-range transported dust  

NASA Astrophysics Data System (ADS)

Transports of bacteria in the atmosphere relate to climate and global hydrological cycles by acting as nuclei of ice-cloud formation, and affect the ecosystems and public health in the downwind ecosystems. Here we present quantitative investigations of airborne bacterial cells coupled with LIVE/DEAD BacLight assay in southwestern Japan to show that airborne bacteria were widespread with Asian dust. Total bacterial cell concentrations in dust varied between 1.0 × 10 6 and 1.6 × 10 7 cells m -3, which were one to two orders higher than those in non-dusty air and were correlated with the concentrations of aerosol particles larger than 1 ?m. The ratio of viable bacterial cells to total bacterial cells (viability) of bacteria in dust ranged from 16 to 40%, which was quite smaller than the viability in non-dusty air. However viable bacterial cell concentrations in dust, 2.5 × 10 5 - 3.8 × 10 6 cells m -3, were similar to or higher than those in non-dusty air. Dust is thus a substantial source of airborne bacterial cells as well as mineral particles. These quantitative results suggest Asian dust is one of the processes for dispersal of airborne bacteria in the global atmosphere.

Hara, Kazutaka; Zhang, Daizhou

2012-02-01

425

Economic History Services  

NSDL National Science Digital Library

Despite its reputation as â??the dismal scienceâ?ť, 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 â??How Much is That?â?ť service. The â??How Much is That?â?ť 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 â??Ask The Professorâ?ť 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 â??Is deflation bad for the economy?â?ť The site also includes a calendar of events for persons interested in learning about upcoming lectures, conferences, workshops, and the like.

426

Economic benefits of supersonic overland operation  

NASA Technical Reports Server (NTRS)

Environmental concerns are likely to impose some restrictions on the next generation of supersonic commercial transport. There is a global concern over the effects of engine emissions on the ozone layer which protects life on Earth from ultraviolet radiation. There is also some concern over community noise. The High Speed Civil Transport (HSCT) must meet at least the current subsonic noise certification standards to be compatible with the future subsonic fleet. Concerns over sonic boom represent another environmental and marketing challenge to the HSCT program. The most attractive feature of the supersonic transport is speed, which offers the traveling public significant time-savings on long range routes. The sonic boom issue represents a major environmental and economic challenge as well. Supersonic operation overland produces the most desirable economic results. However, unacceptable overland sonic boom raise levels may force HSCT to use subsonic speeds overland. These environmental and economic challenges are likely to impose some restrictions on supersonic operation, thus introducing major changes to existing route structures and future supersonic network composition. The current subsonic route structure may have to be altered for supersonic transports to avoid sensitive areas in the stratosphere or to minimize overland flight tracks. It is important to examine the alternative route structure and the impact of these restrictions on the economic viability of the overall supersonic operation. Future market potential for HSCT fleets must be large enough to enable engine and airframe manufacturers to build the plane at a cost that provides them with an attractive return on investment and to sell it at a price that allows the airlines to operate with a reasonable margin of profit. Subsonic overland operation of a supersonic aircraft hinders its economic viability. Ways to increase the market potential of supersonic operation are described.

Metwally, Munir

1992-01-01

427

Two essays in environmental economics: An optimal control approach to cross-media variation in the behavior and effects of pollution, and Exploring the determinants of air quality improvements: An empirical study of trends in particulates  

SciTech Connect

The first essay addresses the problem that society confronts in determining optimal methods of disposing of pollutants. The choice of disposal strategy for any given pollutant often determines the environmental medium into which the pollutant is released. In turn, choice of medium may influence both the persistence of the pollutant and the effects that it has on human health. Because the choice of technology has intertemporal implications, an optimal-control model of the problem of allocating a pollutant between two different disposal methods is formulated and characterized. The second essay presents an empirical test of several hypotheses concerning the determinants of changes in US air quality since the late 1960s. These hypotheses are: (1) incentives established by federal clean air legislation have provided a significant impetus to improvements in air quality; (2) trends in the levels of industrial activities, not caused by federal legislation, have led to declines in pollution; and (3) differences across jurisdictions in socio-economic characteristics and unionization have influenced variations in local trends. Cross-section regression analysis was performed on trends in particulate levels at specific air monitoring sites for two time periods: 1967-77 and 1977-82.

Eiswerth, M.E.

1988-01-01

428

Beekeeping Economics Uniting Beekeeping, Economics, Business, and  

E-print Network

NAME: Beekeeping Economics Uniting Beekeeping, Economics, Business, and Mathematics Part 1: You Don to Beekeeping Economics The goal of Beekeeping Economics is to have you develop a 3-year business plan for a beekeeping business. To start the business, you need money in the form of a business loan. To get

Watkins, Joseph C.

429

A staining method for assessing the viability of Esteya vermicola conidia.  

PubMed

The viability of conidia of Esteya vermicola, a potentially important biocontrol agent against the pinewood nematode Bursaphelenchus xylophilus, is usually determined by cultivation for 18-48 h in culture medium. As an alternative to this labor-intensive method, we have developed a rapid, simple, and low-cost staining method for assessing E vermicola conidia survival rates. A mixture of neutral red and methylene blue was found to be the most optimal among several stains that also included safranin O and Janus green B. This mixture stained nonviable conidia blue, in contrast to viable conidia, which were stained red in the cytoplasm and blue in the cell wall. This method may be particularly useful for traditional research laboratories, as it provides rapid results using common, relatively inexpensive laboratory equipment. PMID:24585076

Wang, Yunbo; Thang, NguyenTrong; Li, Zheng; Zhang, Yongan; Li, Jingjie; Xue, Jianjie; Gu, Lijuan; Hong, VuThuy; Mira, Lee; Sung, Changkeun

2014-07-01

430

Assessment of cellular viability on calcium sulphate/hydroxyapatite injectable scaffolds  

PubMed Central

Cements for maxillofacial reconstruction of jaw defects through calcification of rotated muscle have been tested. The objective of this study was to investigate the visibility of loading of two types of commercially available cements, Cerament™ Spine Support and Cerament Bone Void Filler with mesenchymal cells and cytokines (bone morphogenetic protein) to act as a biomimetic scaffolding for future clinical application. Determination of basic biocompatibility (cell viability) using methyl thiazolyl tetrazolium and live/dead assay was carried out using MG-63 cells at various time points. Next, in order to inform potential subsequent in vivo experiments, a collagen tissue mimic was used for characterization of rabbit mesenchymal stromal cells using immunofluorescent cytoskeleton staining, and simultaneous and then sequential injection of Cerament Spine Support cement and cells into collagen gels. Results indicated that Cerament Spine Support was more biocompatible and that sequential injection of cement and then rabbit mesenchymal stromal cells into the tissue mimics is an optimal approach for clinical applications. PMID:24555009

Naudi, Kurt; Dalby, Matthew J; Tanner, K Elizabeth; McMahon, Jeremy D; Ayoub, Ashraf

2013-01-01

431

Effects of solar radiation on viability of two strains of antarctic bacteria  

SciTech Connect

Since El-Sayed called attention to the potential danger to the southern ocean ecosystem from the enhanced ultraviolet-B (UV-B) radiation which results from the seasonal ozone hole over Antarctica, numerous studies have assessed the impact of solar ultraviolet radiation (UVR) on marine organisms. With just a few exceptions, little effort has been devoted to determining the impact of UVR on marine bacteria. This is a notable omission in efforts to assess the impact of enhanced UV-B radiation on the dynamics of the food web in antarctic waters, because bacterioplankton are believed to have a dominant role in the cycling of organic carbon and nutrients in marine waters. In this article, we present preliminary data obtained at Palmer Station (64.7{degrees}S 64.1{degrees}W) during the months of November and December 1993 on the effects of solar UVR on viability of isolated bacterial strains. 6 refs., 2 figs.

Marguet, E.R. [Universidad Nacional de la Patagonia, Chubut (Argentina); Helbling, E.W.; Villafane, V.E. [Univ. of California, La Jolla, CA (United States)] [and others

1994-12-31

432

Simulation modeling of population viability for the leopard darter (Percidae: Percina pantherina)  

USGS Publications Warehouse

We used the computer program RAMAS to perform a population viability analysis for the leopard darter, Percina pantherina. This percid fish is a threatened species confined to five isolated rivers in the Ouachita Mountains of Oklahoma and Arkansas. A base model created from life history data indicated a 6% probability that the leopard darter would go extinct in 50 years. We performed sensitivity analyses to determine the effects of initial population size, variation in age structure, variation in severity and probability of catastrophe, and migration rate. Catastrophe (modeled as the probability and severity of drought) and migration had the greatest effects on persistence. Results of these simulations have implications for management of this species.

Williams, L.R.; Echelle, A.A.; Toepfer, C.S.; Williams, M.G.; Fisher, W.L.

1999-01-01

433

Translation initiation factor IF1 is essential for cell viability in Escherichia coli.  

PubMed Central

Translation initiation factor IF1 is a highly conserved element of the prokaryotic translational apparatus. It has been demonstrated earlier that the factor stimulates in vitro the initiation phase of protein synthesis. However, no mutation in its gene, infA, has been identified, and a role for IF1 in translation has not been demonstrated in vivo. To elucidate the function of IF1 and determine if the protein is essential for cell growth, the chromosomal copy of infA was disrupted. Cell viability is maintained only when infA is expressed in trans from a plasmid, thereby demonstrating that IF1 is essential for cell growth in Escherichia coli. Cells depleted of IF1 exhibit few polysomes, suggesting that IF1 functions in the initiation phase of protein synthesis. Images PMID:8282696

Cummings, H S; Hershey, J W

1994-01-01

434

Viability of T lymphocytes survived in frozen-thawed human bone marrow.  

PubMed

To know immunocompetence of cryopreserved human bone marrow, an optimal condition for cryopreservation of hemopoietic stem cells was determined on the basis of in vitro colony formation. Viability or immune function of frozen-thawed bone marrow lymphocytes was evaluated by spontaneous rosette formation and sheep red blood cells and mixed lymphocyte culture activity. It was demonstrated that the thawed marrow cells could form E rosettes and respond to alloantigens in mixed lymphocyte culture equally or more than those before freezing. Stimulating activity of cryopreserved marrow cells in mixed lymphocyte culture was not altered through a freeze-thawing process. These observations suggest that bone marrow lymphocytes may survive without losing their immunocompetence after freezing as well as hemopoietic stem cells. PMID:147531

Harada, M; Ishino, C; Hattori, K

1978-04-01

435

Is Your Community Ready for Economic Development?  

E-print Network

A critical step in initiating or facilitating an effective economic development project is to determine if the community is actually prepared to take on such a difficult task. This publication can help community leaders determine how "prepared a...

Saldana, Luis

2003-03-30

436

Visualizing Economics  

NSDL National Science Digital Library

Taking a page from Adam Smith, the motto of this delightful site is "Making the 'Invisible Hand' Visible." Under the guidance of Catherine Mulbrandon, the site brings together economic data and the powerful techniques of information visualization. She does this quite effectively through such thematic maps as "Where do Britain's rich and poor live?" and the "United States Household Income Map". Visitors can make their way through the maps here at their leisure, and also post their comments as they see fit. Additionally, users can look through the "Most Popular Posts" area and sign up to receive updates about new maps via email. Overall, the site is quite a find, and could even be used to spark debate and discussion in the classroom or around the break room.

Mulbrandon, Catherine

437

Rapid-Viability PCR Method for Detection of Live, Virulent Bacillus anthracis in Environmental Samples ?  

PubMed Central

In the event of a biothreat agent release, hundreds of samples would need to be rapidly processed to characterize the extent of contamination and determine the efficacy of remediation activities. Current biological agent identification and viability determination methods are both labor- and time-intensive such that turnaround time for confirmed results is typically several days. In order to alleviate this issue, automated, high-throughput sample processing methods were developed in which real-time PCR analysis is conducted on samples before and after incubation. The method, referred to as rapid-viability (RV)-PCR, uses the change in cycle threshold after incubation to detect the presence of live organisms. In this article, we report a novel RV-PCR method for detection of live, virulent Bacillus anthracis, in which the incubation time was reduced from 14 h to 9 h, bringing the total turnaround time for results below 15 h. The method incorporates a magnetic bead-based DNA extraction and purification step prior to PCR analysis, as well as specific real-time PCR assays for the B. anthracis chromosome and pXO1 and pXO2 plasmids. A single laboratory verification of the optimized method applied to the detection of virulent B. anthracis in environmental samples was conducted and showed a detection level of 10 to 99 CFU/sample with both manual and automated RV-PCR methods in the presence of various challenges. Experiments exploring the relationship between the incubation time and the limit of detection suggest that the method could be further shortened by an additional 2 to 3 h for relatively clean samples. PMID:21764960

Létant, Sonia E.; Murphy, Gloria A.; Alfaro, Teneile M.; Avila, Julie R.; Kane, Staci R.; Raber, Ellen; Bunt, Thomas M.; Shah, Sanjiv R.

2011-01-01

438

Intracellular trehalose and sorbitol synergistically promoting cell viability of a biocontrol yeast, Pichia anomala, for aflatoxin reduction.  

PubMed

Pichia anomala (Wickerhamomyces anomalus) WRL-076 was discovered by a visual screening bioassay for its antagonism against Aspergillus flavus. The yeast was shown to significantly inhibit aflatoxin production and the growth of A. flavus. P. anomala is a potential biocontrol agent for reduction of aflatoxin in the food chain. Maintaining the viability of biocontrol agents in formulated products is a great challenge for commercial applications. Four media, NYG, NYGS, NYGT and NYGST are described which support good growth of yeast cells and were tested as storage formulations. Post growth supplement of 5 % trehalose to NYGST resulted in 83 % viable yeast cells after 12 months in cold storage. Intracellular sorbitol and trehalose concentrations were determined by HPLC analysis at the beginning of the storage and at the end of 12 month. Correlation of cell viability to both trehalose and sorbitol suggested a synergistic effect. Bonferroni (Dunn) t Test, Tukey's Studentized Range (HSD) Test and Duncan's Multiple Range Test, all showed that yeast cell viability in samples with both intracellular trehalose and sorbitol were significantly higher than those with either or none, at a 95 % confidence level. DiBAC4(5) and CFDA-AM were used as the membrane integrity fluorescent stains to create a two-color vital staining scheme with red and green fluorescence, respectively. Yeast cells stored in formulations NYG and NYGS with no detectable trehalose, displayed mostly red fluorescence. Yeast cells in NYGST+5T showed mostly green fluorescence. PMID:25700743

Hua, Sui Sheng T; Hernlem, Bradley J; Yokoyama, Wallace; Sarreal, Siov Bouy L

2015-05-01

439

ToHajiilee Economic Development, Inc.(TEDI) Feasibility Study for Utility-Scale Solar  

SciTech Connect

ToĂ?Â?Hajiilee Economic Development, Inc. (TEDI) is the economic development entity representing the ToHajiilee Chapter of the Navajo Nation, also known as the CaĂ?Â?oncito Band of Navajo (CBN). Using DOE funding, TEDI assembled a team of qualified advisors to conduct a feasibility study for a utility-scale 30 MW Photovoltaic (PV) solar power generation facility on TEDI trust lands. The goal for this project has been to gather information and practical business commitments to successfully complete the feasibility analysis. The TEDI approach was to successively make informed decisions to select an appropriate technology best suited to the site, determine environmental viability of the site, secure options for the sale of generated power, determine practicality of transmission and interconnection of power to the local grid, and secure preliminary commitments on project financing. The feasibility study has been completed and provides TEDI with a practical understanding of its business options in moving forward with developing a solar project on CBN tribal lands. Funding from DOE has allowed TEDI and its team of professional advisors to carefully select technology and business partners and build a business model to develop this utility-scale solar project. As a result of the positive feasibility findings, TEDI is moving forward with finalizing all pre-construction activities for its major renewable energy project.

Burpo, Rob

2012-02-29

440

Viability selection on prey morphology by a generalist predator.  

PubMed

Prey use their locomotory capacity to escape predators, and there should thus be strong viability selection on locomotory morphology of prey. We compared feather morphology of wood pigeons Columba palumbus killed by goshawks Accipiter gentilis with that of survivors to quantify directional and quadratic selection on primary and rectrix feathers. The goshawk is mainly a predator attacking by surprise, leaving wood pigeons with an ability to accelerate fast at a selective advantage. There was directional selection for light primary feathers with a narrow calamus. In addition, there was directional selection for increased area of rectrices. These patterns of natural selection were confirmed in multivariate analyses of selection that showed selection for light primary feathers with a large area and narrow calamus and for a large area of rectrix feathers. These results provide evidence of selection on different aspects of feather morphology directly related to flight performance and thus escape ability from predators. PMID:19344382

Mřller, A P; Couderc, G; Nielsen, J T

2009-06-01

441

Dual fluorochrome flow cytometric assessment of yeast viability.  

PubMed

A novel staining protocol is reported for the assessment of viability in yeast, specifically the biocontrol yeast, Pichia anomala. Employing both the red fluorescent membrane potential sensitive oxonol stain DiBAC(4)(5) (Bis-(1,3-dibutylbarbituric acid)pentamethine oxonol), a structural analog of the commonly used DiBAC(4)(3) (Bis-(1,3-dibutylbarbituric acid)trimethine oxonol), with one of the esterase dependent green fluorogenic probes such as CFDA-AM (5-Carboxyfluorescein diacetate, acetoxymethyl ester) or Calcein-AM (Calcein acetoxymethyl ester), a two-color flow cytometric method was developed, which yields rapid quantitative information on the vitality and vigor of yeast cell cultures. The method was validated by cell sorting and analysis of live, heat killed, and UV-treated yeast. PMID:20049598

Hernlem, Bradley; Hua, Sui-Sheng

2010-07-01

442

Glycolytic Metabolites Are Critical Modulators of Oocyte Maturation and Viability  

PubMed Central

The maturation of an oocyte into an egg is a key step in preparation for fertilization. In Xenopus, oocyte maturation is independent of transcription, being regulated at the level of translation and post-translational modifications of proteins. To identify factors involved in the maturation process we used two-dimensional differential gel electrophoresis to compare the proteome of oocytes and eggs. Protein abundance changes were observed in multiple cellular pathways during oocyte maturation. Most prominent was a general reduction in abundance of enzymes in the glycolytic pathway. Injection into oocytes of the glycolytic intermediates glyceraldehyde-3-phosphate, phosphoenolpyruvate and glucose-6-phosphate prevented oocyte maturation. Instead, these metabolites stimulated ROS production and subsequent apoptosis of the oocyte. In contrast, all other metabolites tested had no effect on oocyte maturation and did not induce apoptosis. These data suggest that a subset of glycolytic metabolites have the capacity to regulate oocyte viability. PMID:24167578

Berger, Lloyd; Wilde, Andrew

2013-01-01

443