Measuring efficiency of cotton cultivation in Pakistan: a restricted production frontier study.

PubMed

Watto, Muhammad Arif; Mugera, Amin

2014-11-01

Massive groundwater pumping for irrigation has started lowering water tables rapidly in different regions of Pakistan. Declining water tables have thus prompted research efforts to improve agricultural productivity and efficiency to make efficient use of scarce water resources. This study employs a restricted stochastic production frontier to estimate the level of, and factors affecting, technical efficiency of groundwater-irrigated cotton farms in the Punjab province of Pakistan. The mean technical efficiency estimates indicate substantial technical inefficiencies among cotton growers. On average, tube-well owners and water buyers can potentially increase cotton production by 19% and 28%, respectively, without increasing the existing input level. The most influential factors affecting technical efficiency positively are the use of improved quality seed, consultation with extension field staff and farmers' perceptions concerning the availability of groundwater resources for irrigation in the future. This study proposes that adopting improved seed for new cotton varieties and providing better extension services regarding cotton production technology would help to achieve higher efficiency in cotton farming. Within the context of falling water tables, educating farmers about the actual crop water requirements and guiding them about groundwater resource availability may also help to achieve higher efficiencies. © 2014 Society of Chemical Industry. © 2014 Society of Chemical Industry.

Lessons from the Specific Factors Model of International Trade.

ERIC Educational Resources Information Center

Tohamy, Soumaya M.; Mixon, J. Wilson, Jr.

2003-01-01

Uses the Specific Factors model to illustrate the meaning of economic efficiency, how complex economies simultaneously determine prices and quantities, and how changes in demand conditions or technology can affect income distribution among owners of factors of production. Employs spreadsheets to help students see how the model works. (JEH)

Resolution V fractional factorial design for screening of factors affecting weakly basic drugs liposomal systems.

PubMed

Nageeb El-Helaly, Sara; Habib, Basant A; Abd El-Rahman, Mohamed K

2018-07-01

This study aims to investigate factors affecting weakly basic drugs liposomal systems. Resolution V fractional factorial design (2 V 5-1 ) is used as an example of screening designs that would better be used as a wise step before proceeding with detailed factors effects or optimization studies. Five factors probable to affect liposomal systems of weakly basic drugs were investigated using Amisulpride as a model drug. Factors studied were; A: Preparation technique B: Phosphatidyl choline (PhC) amount (mg) C: Cholesterol: PhC molar ratio, D: Hydration volume (ml) and E: Sonication type. Levels investigated were; Ammonium sulphate-pH gradient technique or Transmembrane zinc chelation-pH gradient technique, 200 or 400 mg, 0 or 0.5, 10 or 20 ml and bath or probe sonication for A, B, C, D and E respectively. Responses measured were Particle size (PS) (nm), Zeta potential (ZP) (mV) and Entrapment efficiency percent (EE%). Ion selective electrode was used as a novel method for measuring unentrapped drug concentration and calculating entrapment efficiency without the need for liposomal separation. Factors mainly affecting the studied responses were Cholesterol: PhC ratio and hydration volume for PS, preparation technique for ZP and preparation technique and hydration volume for EE%. The applied 2 V 5-1 design enabled the use of only 16 trial combinations for screening the influence of five factors on weakly basic drugs liposomal systems. This clarifies the value of the use of screening experiments before extensive investigation of certain factors in detailed optimization studies. Copyright © 2018 Elsevier B.V. All rights reserved.

Evaluating the Efficiency of Research in Academic Departments: An Empirical Analysis in an Italian Region

ERIC Educational Resources Information Center

Agasisti, Tommaso; Dal Bianco, Antonio; Landoni, Paolo; Sala, Alessandro; Salerno, Mario

2011-01-01

This paper investigates the efficiency of university departments in science, technology and medicine in an Italian Region (Lombardy). The aim of the paper is twofold: (i) to analyse the changes in productivity in recent years (from 2004 and 2007); and (ii) to detect factors that are potentially affecting efficiency. The research benefited from a…

Affect asymmetry and comfort food consumption.

PubMed

Dubé, Laurette; LeBel, Jordan L; Lu, Ji

2005-11-15

It is proposed that the emotional triggers of comfort food consumption can reliably be predicted by factors tied to affect asymmetry whereby negative affects dominate one's experience, decision making and behaviors in some instances while positive emotions prevail in others. Specifically, we relate three of these factors (age, gender, and culture) to differences in the emotional triggers of comfort food consumption and we further explore the possibility that the type of food eaten during comfort-seeking episodes can also be tied to affect asymmetry. Two hundred and seventy-seven participants completed a web-based survey conducted to assess the emotional antecedents and consequences of comfort food consumption. Consistent with expectations, results indicate that men's comfort food consumption was motivated by positive emotions whereas women's consumption was triggered by negative affects. Consumption of comfort foods alleviated women's negative emotions but also produced guilt. Positive affect was a particularly powerful trigger of comfort food consumption for older participants and for participants with French cultural background. Younger participants and participants with English background reported more intense negative emotions prior to consuming comfort foods. Foods high in sugar and fat content were more efficient in alleviating negative affects whereas low-calorie foods were more efficient in increasing positive emotions.

Factors affecting the efficient transformation of Colletotrichum species

USGS Publications Warehouse

Redman, Regina S.; Rodriguez, Rusty J.

1994-01-01

Factors affecting the efficient transformation of Colletotrichum species. Experimental Mycology, 18, 230-246. Twelve isolates representing four species of Colletotrichum were transformed either by enhanced protoplast, restriction enzyme-mediated integration (REMI), or electroporation-mediated protocols. The enhanced protoplast transformation protocol resulted in 100- and 50-fold increases in the transformation efficiencies of Colletotrichum lindemuthianum and C. magna , respectively. REMI transformation involved the use of Hin dIII and vector DNA linearized with HindIII to increase the number of integration events and potential gene disruptions in the fungal genome. Combining the enhanced protoplast and the REMI protocols resulted in a 22-fold increase in the number of hygromycin/nystatin-resistant mutants in C. lindemuthianum . Electroporation-mediated transformation was performed on mycelial fragments and spores of four Colletotrichum species, resulting in efficiencies of up to 1000 transformants/μg DNA. The pHA1.3 vector which confers hygromycin resistance contains telomeric sequences from Fusarium oxysporum , transforms by autonomous replication and genomic integration, and was essential for elevated transformation efficiencies of 100 to 10,000 transformants/μg DNA. Modifications of pHA1.3 occurred during bacterial amplification and post fungal transformation resulting in plasmids capable of significantly elevated transformation efficiencies in C. lindemuthianum.

Identifying Nonprovider Factors Affecting Pediatric Emergency Medicine Provider Efficiency.

PubMed

Saleh, Fareed; Breslin, Kristen; Mullan, Paul C; Tillett, Zachary; Chamberlain, James M

2017-10-31

The aim of this study was to create a multivariable model of standardized relative value units per hour by adjusting for nonprovider factors that influence efficiency. We obtained productivity data based on billing records measured in emergency relative value units for (1) both evaluation and management of visits and (2) procedures for 16 pediatric emergency medicine providers with more than 750 hours worked per year. Eligible shifts were in an urban, academic pediatric emergency department (ED) with 2 sites: a tertiary care main campus and a satellite community site. We used multivariable linear regression to adjust for the impact of shift and pediatric ED characteristics on individual-provider efficiency and then removed variables from the model with minimal effect on productivity. There were 2998 eligible shifts for the 16 providers during a 3-year period. The resulting model included 4 variables when looking at both ED sites combined. These variables include the following: (1) number of procedures billed by provider, (2) season of the year, (3) shift start time, and (4) day of week. Results were improved when we separately modeled each ED location. A 3-variable model using procedures billed by provider, shift start time, and season explained 23% of the variation in provider efficiency at the academic ED site. A 3-variable model using procedures billed by provider, patient arrivals per hour, and shift start time explained 45% of the variation in provider efficiency at the satellite ED site. Several nonprovider factors affect provider efficiency. These factors should be considered when designing productivity-based incentives.

Analysis of the restricting factors of laser countermeasure active detection technology

NASA Astrophysics Data System (ADS)

Zhang, Yufa; Sun, Xiaoquan

2016-07-01

The detection effect of laser active detection system is affected by various kinds of factors. In view of the application requirement of laser active detection, the influence factors for laser active detection are analyzed. The mathematical model of cat eye target detection distance has been built, influence of the parameters of laser detection system and the environment on detection range and the detection efficiency are analyzed. Various parameters constraint detection performance is simulated. The results show that the discovery distance of laser active detection is affected by the laser divergence angle, the incident angle and the visibility of the atmosphere. For a given detection range, the laser divergence angle and the detection efficiency are mutually restricted. Therefore, in view of specific application environment, it is necessary to select appropriate laser detection parameters to achieve optimal detection effect.

Application and analysis of debris-flow early warning system in Wenchuan earthquake-affected area

NASA Astrophysics Data System (ADS)

Liu, D. L.; Zhang, S. J.; Yang, H. J.; Zhao, L. Q.; Jiang, Y. H.; Tang, D.; Leng, X. P.

2016-02-01

The activities of debris flow (DF) in the Wenchuan earthquake-affected area significantly increased after the earthquake on 12 May 2008. The safety of the lives and property of local people is threatened by DFs. A physics-based early warning system (EWS) for DF forecasting was developed and applied in this earthquake area. This paper introduces an application of the system in the Wenchuan earthquake-affected area and analyzes the prediction results via a comparison to the DF events triggered by the strong rainfall events reported by the local government. The prediction accuracy and efficiency was first compared with a contribution-factor-based system currently used by the weather bureau of Sichuan province. The storm on 17 August 2012 was used as a case study for this comparison. The comparison shows that the false negative rate and false positive rate of the new system is, respectively, 19 and 21 % lower than the system based on the contribution factors. Consequently, the prediction accuracy is obviously higher than the system based on the contribution factors with a higher operational efficiency. On the invitation of the weather bureau of Sichuan province, the authors upgraded their prediction system of DF by using this new system before the monsoon of Wenchuan earthquake-affected area in 2013. Two prediction cases on 9 July 2013 and 10 July 2014 were chosen to further demonstrate that the new EWS has high stability, efficiency, and prediction accuracy.

Basics for sensorimotor information processing: some implications for learning

PubMed Central

Vidal, Franck; Meckler, Cédric; Hasbroucq, Thierry

2015-01-01

In sensorimotor activities, learning requires efficient information processing, whether in car driving, sport activities or human–machine interactions. Several factors may affect the efficiency of such processing: they may be extrinsic (i.e., task-related) or intrinsic (i.e., subjects-related). The effects of these factors are intimately related to the structure of human information processing. In the present article we will focus on some of them, which are poorly taken into account, even when minimizing errors or their consequences is an essential issue at stake. Among the extrinsic factors, we will discuss, first, the effects of the quantity and quality of information, secondly, the effects of instruction and thirdly motor program learning. Among the intrinsic factors, we will discuss first the influence of prior information, secondly how individual strategies affect performance and, thirdly, we will stress the fact that although the human brain is not structured to function errorless (which is not new) humans are able to detect their errors very quickly and (in most of the cases), fast enough to correct them before they result in an overt failure. Extrinsic and intrinsic factors are important to take into account for learning because (1) they strongly affect performance, either in terms of speed or accuracy, which facilitates or impairs learning, (2) the effect of certain extrinsic factors may be strongly modified by learning and (3) certain intrinsic factors might be exploited for learning strategies. PMID:25762944

Light intensity affects RNA silencing of a transgene in Nicotiana benthamiana plants.

PubMed

Kotakis, Christos; Vrettos, Nicholas; Kotsis, Dimitrios; Tsagris, Mina; Kotzabasis, Kiriakos; Kalantidis, Kriton

2010-10-12

Expression of exogenous sequences in plants is often suppressed through one of the earliest described RNA silencing pathways, sense post-transcriptional gene silencing (S-PTGS). This type of suppression has made significant contributions to our knowledge of the biology of RNA silencing pathways and has important consequences in plant transgenesis applications. Although significant progress has been made in recent years, factors affecting the stability of transgene expression are still not well understood. It has been shown before that the efficiency of RNA silencing in plants is influenced by various environmental factors. Here we report that a major environmental factor, light intensity, significantly affects the induction and systemic spread of S-PTGS. Moreover, we show that photoadaptation to high or low light intensity conditions differentially affects mRNA levels of major components of the RNA silencing machinery. Light intensity is one of the previously unknown factors that affect transgene stability at the post-transcriptional level. Our findings demonstrate an example of how environmental conditions could affect RNA silencing.

[Quality level assessment of lowly efficient Tamarix chinensis secondary shrubs in Laizhou Bay of Yellow River Delta].

PubMed

Xia, Jiang-Bao; Liu, Yu-Ting; Zhu, Jin-Fang; Xu, Jing-Wei; Lu, Zhao-Hua; Liu, Jing-Tao; Liu, Qing

2013-06-01

Taking the Tamarix chinensis secondary shrubs in Laizhou Bay of Yellow River Delta as test objects, and by using synthetic factor method, this paper studied the main factors causing the lowly efficiency of T. chinensis secondary shrubs as well as the main parameters for the classification of lowly efficient T. chinensis secondary shrubs. A total of 24 indices including shrubs growth and soil physical and chemical properties were selected to determine the main affecting factors and parameters in evaluating and classifying the lowly efficient shrubs. There were no obvious correlations between the indices reflecting the shrubs growth and soil quality, and thus, only using shrub growth index to reflect the lowly efficiency level of T. chinensis was not enough, and it would be necessary to combine with soil quality factors to make a comprehensive evaluation. The principal factors reflecting the quality level of lowly efficient T. chinensis shrubs included soil salt content and moisture content, stand age, single tree's aboveground stem, leaf biomass, and basal diameter, followed by soil density, porosity, and soil nutrient status. The lowly efficient T. chinensis shrubs in the Bay could be classified into five types, namely, shrub with growth potential, slightly low quality shrub, moderately lowly efficient shrub, moderately low quality and lowly efficient shrub, and seriously low quality and lowly efficient shrub. The main features, low efficiency causes, and management measures of these shrubs were discussed based on the mean cluster value.

Microgrid Study: Energy Security for DoD Installations

DTIC Science & Technology

2012-06-18

security, efficiency, and the incorporation of renewable and distributed energy resources into microgrids, as well as the factors that might facilitate...better understand how different environmental factors affected the choice of optimal microgrid architecture. Environmental factors in this context...lower costs—Networking generation assets allow for load sharing, allowing fewer generators to run at higher load factors and therefore with greater

European regional efficiency and geographical externalities: a spatial nonparametric frontier analysis

NASA Astrophysics Data System (ADS)

Ramajo, Julián; Cordero, José Manuel; Márquez, Miguel Ángel

2017-10-01

This paper analyses region-level technical efficiency in nine European countries over the 1995-2007 period. We propose the application of a nonparametric conditional frontier approach to account for the presence of heterogeneous conditions in the form of geographical externalities. Such environmental factors are beyond the control of regional authorities, but may affect the production function. Therefore, they need to be considered in the frontier estimation. Specifically, a spatial autoregressive term is included as an external conditioning factor in a robust order- m model. Thus we can test the hypothesis of non-separability (the external factor impacts both the input-output space and the distribution of efficiencies), demonstrating the existence of significant global interregional spillovers into the production process. Our findings show that geographical externalities affect both the frontier level and the probability of being more or less efficient. Specifically, the results support the fact that the spatial lag variable has an inverted U-shaped non-linear impact on the performance of regions. This finding can be interpreted as a differential effect of interregional spillovers depending on the size of the neighboring economies: positive externalities for small values, possibly related to agglomeration economies, and negative externalities for high values, indicating the possibility of production congestion. Additionally, evidence of the existence of a strong geographic pattern of European regional efficiency is reported and the levels of technical efficiency are acknowledged to have converged during the period under analysis.

Factors Affecting Regional Per-Capita Carbon Emissions in China Based on an LMDI Factor Decomposition Model

PubMed Central

Dong, Feng; Long, Ruyin; Chen, Hong; Li, Xiaohui; Yang, Qingliang

2013-01-01

China is considered to be the main carbon producer in the world. The per-capita carbon emissions indicator is an important measure of the regional carbon emissions situation. This study used the LMDI factor decomposition model–panel co-integration test two-step method to analyze the factors that affect per-capita carbon emissions. The main results are as follows. (1) During 1997, Eastern China, Central China, and Western China ranked first, second, and third in the per-capita carbon emissions, while in 2009 the pecking order changed to Eastern China, Western China, and Central China. (2) According to the LMDI decomposition results, the key driver boosting the per-capita carbon emissions in the three economic regions of China between 1997 and 2009 was economic development, and the energy efficiency was much greater than the energy structure after considering their effect on restraining increased per-capita carbon emissions. (3) Based on the decomposition, the factors that affected per-capita carbon emissions in the panel co-integration test showed that Central China had the best energy structure elasticity in its regional per-capita carbon emissions. Thus, Central China was ranked first for energy efficiency elasticity, while Western China was ranked first for economic development elasticity. PMID:24353753

Factors affecting regional per-capita carbon emissions in China based on an LMDI factor decomposition model.

PubMed

Dong, Feng; Long, Ruyin; Chen, Hong; Li, Xiaohui; Yang, Qingliang

2013-01-01

China is considered to be the main carbon producer in the world. The per-capita carbon emissions indicator is an important measure of the regional carbon emissions situation. This study used the LMDI factor decomposition model-panel co-integration test two-step method to analyze the factors that affect per-capita carbon emissions. The main results are as follows. (1) During 1997, Eastern China, Central China, and Western China ranked first, second, and third in the per-capita carbon emissions, while in 2009 the pecking order changed to Eastern China, Western China, and Central China. (2) According to the LMDI decomposition results, the key driver boosting the per-capita carbon emissions in the three economic regions of China between 1997 and 2009 was economic development, and the energy efficiency was much greater than the energy structure after considering their effect on restraining increased per-capita carbon emissions. (3) Based on the decomposition, the factors that affected per-capita carbon emissions in the panel co-integration test showed that Central China had the best energy structure elasticity in its regional per-capita carbon emissions. Thus, Central China was ranked first for energy efficiency elasticity, while Western China was ranked first for economic development elasticity.

Isolation and characterization of lost copper and molybdenum particles in the flotation tailings of Kennecott copper porphyry ores

NASA Astrophysics Data System (ADS)

Tserendavga, Tsend-Ayush

The importance of flotation separation has long been, and continues to be, an important technology for the mining industry, especially to metallurgical engineers. However, the flotation process is quite complex and expensive, in addition to being influenced by many variables. Understanding the variables affecting flotation efficiency and how valuable minerals are lost to the tailings gives metallurgists an advantage in their attempts to increase efficiency by designing operations to target the areas of greatest potential value. A successful, accurate evaluation of lost minerals in the tailings and appropriate solutions to improve flotation efficiency can save millions of dollars in the effective utilization of our mineral resources. In this dissertation research, an attempt has been made to understand the reasons for the loss of valuable mineral particles in the tailings from Kennecott Utah Copper ores. Possibilities include liberation, particle aggregation (slime coating) and surface chemistry issues associated with the flotation separation. This research generally consisted of three main aspects. The first part involved laboratory flotation experiments and factors, which affect the flotation efficiency. Results of flotation testing are reported that several factors such as mineral exposure/liberation and slime coating and surface oxidation strongly affect the flotation efficiency. The second part of this dissertation research was to develop a rapid scan dual energy (DE) methodology using 2D radiography to identify, isolate, and prepare lost sulfide mineral particles with the advantages of simple sample preparation, short analysis time, statistically reliable accuracy and confident identification. The third part of this dissertation research was concerned with detailed characterization of lost particles including such factors as liberation, slime coating, and surface chemistry characteristics using advanced analytical techniques and instruments. Based on the results from characterization, the extent to which these factors contribute to the loss of sulfide mineral particles in the tailings were determined.

Factors Affecting Item Difficulty in English Listening Comprehension Tests

ERIC Educational Resources Information Center

Sung, Pei-Ju; Lin, Su-Wei; Hung, Pi-Hsia

2015-01-01

Task difficulty is a critical issue affecting test developers. Controlling or balancing the item difficulty of an assessment improves its validity and discrimination. Test developers construct tests from the cognitive perspective, by making the test constructing process more scientific and efficient; thus, the scores obtained more precisely…

Accurate Determination of Coulombic Efficiency for Lithium Metal Anodes and Lithium Metal Batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adams, Brian D.; Zheng, Jianming; Ren, Xiaodi

Lithium (Li) metal is an ideal anode material for high energy density batteries. However, its low Coulombic efficiency (CE) and formation of dendrites during the plating and stripping processes has hindered its applications in rechargeable Li metal batteries. The accurate measurement of Li CE is a critical factor to predict the cycle life of Li metal batteries, but the measurement of Li CE is affected by various factors that often leads to conflicting values reported in the literature. Here, we investigate various factors that affect the measurement of Li CE and propose a more accurate method of determining Li CE.more » It was also found that the capacity used for cycling greatly affects the stabilization cycles and the average CE. A higher cycling capacity leads to a shorter number of stabilization cycles and higher average CE. With a proper high-concentration ether-based electrolyte, Li metal can be cycled with a high average CE of 99.5 % for over 100 cycles at a high capacity of 6 mAh cm-2 suitable for practical applications.« less

Size, Loading Efficiency, and Cytotoxicity of Albumin-Loaded Chitosan Nanoparticles: An Artificial Neural Networks Study.

PubMed

Baharifar, Hadi; Amani, Amir

2017-01-01

When designing nanoparticles for drug delivery, many variables such as size, loading efficiency, and cytotoxicity should be considered. Usually, smaller particles are preferred in drug delivery because of longer blood circulation time and their ability to escape from immune system, whereas smaller nanoparticles often show increased toxicity. Determination of parameters which affect size of particles and factors such as loading efficiency and cytotoxicity could be very helpful in designing drug delivery systems. In this work, albumin (as a protein drug model)-loaded chitosan nanoparticles were prepared by polyelectrolyte complexation method. Simultaneously, effects of 4 independent variables including chitosan and albumin concentrations, pH, and reaction time were determined on 3 dependent variables (i.e., size, loading efficiency, and cytotoxicity) by artificial neural networks. Results showed that concentrations of initial materials are the most important factors which may affect the dependent variables. A drop in the concentrations decreases the size directly, but they simultaneously decrease loading efficiency and increase cytotoxicity. Therefore, an optimization of the independent variables is required to obtain the most useful preparation. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Gravity as a factor in the animal environment.

NASA Technical Reports Server (NTRS)

Smith, A. H.

1972-01-01

Review of current knowledge, research, and research planning on the influence of gravity upon living organisms. Discussed factors affecting the adaptability of animals to increased acceleration fields include age, sex, posture, and body size. Affected functions and aspects reviewed cover growth and mature body size, body composition, maintenance feed requirements, and feed utilization efficiency. It is expected that research involving the exposure of animals to altered gravity states will lead to new biological concepts of very broad importance.

[Research on mercury methylation by Geobacter sulfurreducens and its influencing factors].

PubMed

Zou, Yan; Si, You-Bin; Yan, Xue; Chen, Yan

2012-09-01

Mercury methylation by Geobacter sulfurreducens and the effects of environmental factors were studied under laboratory conditions. The results showed that G. sulfurreducens could grow well in the presence of low concentrations of mercuric chloride, but its growth was inhibited to a certain extent, mainly expressed in the prolonged lag phase. G. sulfurreducens could transform inorganic mercury into methylmercury, and this process was affected by many environmental factors. The efficiency of mercury methylation reached 38% under anaerobic conditions with 1 mg x L(-1) HgCl2 and 0.9% salinity at 35 degrees C, pH 6.0. Increasing the initial HgCl2 concentration or salinity in an appropriate manner improved mercury methylation, but the concentration of methylmercury reduced when the concentrations of HgCl2 and salinity were too high. The efficiency of mercury methylation increased with the increasing temperature in range of 4-35 degrees C. Weakly acidic environment was more beneficial to mercury methylation than acidic, neutral or alkaline conditions. In addition, the efficiency of mercury methylation was also affected by humic acid and cysteine. Humic acid inhibited mercury methyaltion, whereas cysteine could improve the efficiency of mercury methylation. This study provided a direct evidence for mercury methylation mediated by iron-reducing bacteria in the natural aquatic ecosystem.

Nitrogen fertilizer rate affects root exudation, the rhizosphere microbiome and nitrogen-use-efficiency of maize

USDA-ARS?s Scientific Manuscript database

The composition and function of microbial communities present in the rhizosphere of crops has been linked to edaphic factors and root exudate composition. In this paper, we examined the effect of N fertilizer rate on maize root exudation, the associated rhizosphere community, and nitrogen-use-effici...

Soil and environmental factors affecting internal N efficiency of maize

USDA-ARS?s Scientific Manuscript database

The inverse of internal N efficiency (IE), N needed per quantity of grain produced, is used in yield-goal based N recommendations to determine the target quantity of N needed to attain a chosen maize yield. Often the value of IE is considered static, irrespective of environment. Evaluation of 47 sit...

Energy efficiency in U.K. shopping centres

NASA Astrophysics Data System (ADS)

Mangiarotti, Michela

Energy efficiency in shopping centres means providing comfortable internal environment and services to the occupants with minimum energy use in a cost-effective and environmentally sensitive manner. This research considers the interaction of three factors affecting the energy efficiency of shopping centres: i) performance of the building fabric and services ii) management of the building in terms of operation, control, maintenance and replacement of the building fabric and services, and company's energy policy iii) occupants' expectation for comfort and awareness of energy efficiency. The aim of the investigation is to determine the role of the above factors in the energy consumption and carbon emissions of shopping centres and the scope for reducing this energy usage by changing one or all the three factors. The study also attempts to prioritize the changes in the above factors that are more cost-effective at reducing that energy consumption and identify the benefits and main economic and legal drivers for energy efficiency in shopping centres. To achieve these targets, three case studies have been analysed. Using energy data from bills, the performance of the selected case studies has been assessed to establish trends and current energy consumption and carbon emissions of shopping centres and their related causes. A regression analysis has attempted to break down the energy consumption of the landlords' area by end-use to identify the main sources of energy usage and consequently introduce cost-effective measures for saving energy. A monitoring and occupants' survey in both landlords' and tenants' areas have been carried out at the same time to compare the objective data of the environmental conditions with the subjective impressions of shoppers and shopkeepers. In particular, the monitoring aimed at assessing the internal environment to identify possible causes of discomfort and opportunities for introducing energy saving measures. The survey looked at determining the occupants' expectation for comfort and awareness of energy efficiency in shopping centres. The results show the complexity of prioritizing the three factors affecting energy efficiency in shopping centres, highlighting the relationships between those factors, and the role of different actors, involved in the life of shopping centres, in the energy and environmental performance of these buildings.

Technical efficiency and productivity of Chinese county hospitals: an exploratory study in Henan province, China.

PubMed

Cheng, Zhaohui; Tao, Hongbing; Cai, Miao; Lin, Haifeng; Lin, Xiaojun; Shu, Qin; Zhang, Ru-Ning

2015-09-09

Chinese county hospitals have been excessively enlarging their scale during the healthcare reform since 2009. The purpose of this paper is to examine the technical efficiency and productivity of county hospitals during the reform process, and to determine whether, and how, efficiency is affected by various factors. 114 sample county hospitals were selected from Henan province, China, from 2010 to 2012. Data envelopment analysis was employed to estimate the technical and scale efficiency of sample hospitals. The Malmquist index was used to calculate productivity changes over time. Tobit regression was used to regress against 4 environmental factors and 5 institutional factors that affected the technical efficiency. (1) 112 (98.2%), 112 (98.2%) and 104 (91.2%) of the 114 sample hospitals ran inefficiently in 2010, 2011 and 2012, with average technical efficiency of 0.697, 0.748 and 0.790, respectively. (2) On average, during 2010-2012, productivity of sample county hospitals increased by 7.8%, which was produced by the progress in technical efficiency changes and technological changes of 0.9% and 6.8%, respectively. (3) Tobit regression analysis indicated that government subsidy, hospital size with above 618 beds and average length of stay assumed a negative sign with technical efficiency; bed occupancy rate, ratio of beds to nurses and ratio of nurses to physicians assumed a positive sign with technical efficiency. There was considerable space for technical efficiency improvement in Henan county hospitals. During 2010-2012, sample hospitals experienced productivity progress; however, the adverse change in pure technical efficiency should be emphasised. Moreover, according to the Tobit results, policy interventions that strictly supervise hospital bed scale, shorten the average length of stay and coordinate the proportion among physicians, nurses and beds, would benefit hospital efficiency. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Technical efficiency and productivity of Chinese county hospitals: an exploratory study in Henan province, China

PubMed Central

Cheng, Zhaohui; Tao, Hongbing; Cai, Miao; Lin, Haifeng; Lin, Xiaojun; Shu, Qin; Zhang, Ru-ning

2015-01-01

Objectives Chinese county hospitals have been excessively enlarging their scale during the healthcare reform since 2009. The purpose of this paper is to examine the technical efficiency and productivity of county hospitals during the reform process, and to determine whether, and how, efficiency is affected by various factors. Setting and participants 114 sample county hospitals were selected from Henan province, China, from 2010 to 2012. Outcome measures Data envelopment analysis was employed to estimate the technical and scale efficiency of sample hospitals. The Malmquist index was used to calculate productivity changes over time. Tobit regression was used to regress against 4 environmental factors and 5 institutional factors that affected the technical efficiency. Results (1) 112 (98.2%), 112 (98.2%) and 104 (91.2%) of the 114 sample hospitals ran inefficiently in 2010, 2011 and 2012, with average technical efficiency of 0.697, 0.748 and 0.790, respectively. (2) On average, during 2010–2012, productivity of sample county hospitals increased by 7.8%, which was produced by the progress in technical efficiency changes and technological changes of 0.9% and 6.8%, respectively. (3) Tobit regression analysis indicated that government subsidy, hospital size with above 618 beds and average length of stay assumed a negative sign with technical efficiency; bed occupancy rate, ratio of beds to nurses and ratio of nurses to physicians assumed a positive sign with technical efficiency. Conclusions There was considerable space for technical efficiency improvement in Henan county hospitals. During 2010–2012, sample hospitals experienced productivity progress; however, the adverse change in pure technical efficiency should be emphasised. Moreover, according to the Tobit results, policy interventions that strictly supervise hospital bed scale, shorten the average length of stay and coordinate the proportion among physicians, nurses and beds, would benefit hospital efficiency. PMID:26353864

The Impact of Cooperative Video Games on Team Cohesion

ERIC Educational Resources Information Center

Anderson, Greg

2010-01-01

In today's economy, productivity and efficiency require collaboration between employees. In order to improve collaboration the factors affecting teamwork must be examined to identify where changes can be made in order to increase performance. One factor contributing to teamwork is team cohesion and represents a process whereby members are joined…

Measuring Search Efficiency in Complex Visual Search Tasks: Global and Local Clutter

ERIC Educational Resources Information Center

Beck, Melissa R.; Lohrenz, Maura C.; Trafton, J. Gregory

2010-01-01

Set size and crowding affect search efficiency by limiting attention for recognition and attention against competition; however, these factors can be difficult to quantify in complex search tasks. The current experiments use a quantitative measure of the amount and variability of visual information (i.e., clutter) in highly complex stimuli (i.e.,…

Improvements in cloning efficiencies may be possible by increasing uniformity in recipient oocytes and donor cells.

PubMed

Miyoshi, Kazuchika; Rzucidlo, S Jacek; Pratt, Scott L; Stice, Steven L

2003-04-01

The low efficiency of somatic cell cloning is the major obstacle to widespread use of this technology. Incomplete nuclear reprogramming following the transfer of donor nuclei into recipient oocytes has been implicated as a primary reason for the low efficiency of the cloning procedure. The mechanisms and factors that affect the progression of the nuclear reprogramming process have not been completely elucidated, but the identification of these factors and their subsequent manipulation would increase cloning efficiency. At present, many groups are studying donor nucleus reprogramming. Here, we present an approach in which the efficiency of producing viable offspring is improved by selecting recipient oocytes and donor cells that will produce cloned embryos with functionally reprogrammed nuclei. This approach will produce information useful in future studies aimed at further deciphering the nuclear reprogramming process.

Photovoltaic Power Systems: A Tour Through the Alternatives

ERIC Educational Resources Information Center

Kelly, Henry

1978-01-01

Photovoltaic systems are examined as potentially major energy sources, along with the economic factors that will affect their future use. Cell design, power efficiency, and manufacturing problems are also considered. (MA)

Exploring Contextual Factors and Patient Activation: Evidence from a Nationally Representative Sample of Patients with Depression

ERIC Educational Resources Information Center

Chen, Jie; Mortensen, Karoline; Bloodworth, Robin

2014-01-01

Patient activation has been considered as a "blockbuster drug of the century." Patients with mental disorders are less activated compared to patients with other chronic diseases. Low activation due to mental disorders can affect the efficiency of treatment of other comorbidities. Contextual factors are significantly associated with…

Impact of environmental production conditions on productivity and efficiency: a case study of wheat farmers in Bangladesh.

PubMed

Rahman, Sanzidur; Hasan, M Kamrul

2008-09-01

Environmental conditions significantly affect production, but are often ignored in studies analysing productivity and efficiency leading to biased results. In this study, we examine the influence of selected environmental factors on productivity and efficiency in wheat farming in Bangladesh. Results reveal that environmental production conditions significantly affect the parameters of the production function and technical efficiency, as well as correlates of inefficiency. Controlling for environmental production conditions improves technical efficiency by 4 points (p<0.01) from 86% to 90%. Large farms are more efficient relative to small and medium sized farms (p<0.01 and 0.05), with no variation among regions. Policy implications include soil fertility improvement through soil conservation and crop rotation, improvement in managerial practices through extension services and adoption of modern technologies, promotion of education, strengthening the research-extension link, and development of new varieties that have higher yield potential and are also suitable for marginal areas.

20 CFR 405.317 - Objections.

Code of Federal Regulations, 2013 CFR

2013-04-01

... requesting the change and the impact of the proposed change on the efficient administration of the hearing process. Factors affecting the impact of the change include, but are not limited to, the effect on the...

Modeling genetic and non-genetic variation of feed efficiency and its partial relationships between component traits as a function of management and environmental factors

USDA-ARS?s Scientific Manuscript database

Feed efficiency (FE), characterized as the ability to convert feed nutrients into saleable milk or meat directly affects the profitability of dairy production, is of increasing economic importance in the dairy industry. We conjecture that FE is a complex trait whose variation and relationships or pa...

Optimization of factors affecting hexavalent chromium removal from simulated electroplating wastewater by synthesized magnetite nanoparticles.

PubMed

Ataabadi, Mitra; Hoodaji, Mehran; Tahmourespour, Arezoo; Kalbasi, Mahmoud; Abdouss, Majid

2015-01-01

Hexavalent chromium is a mutagen and carcinogen that is of significant concern in water and wastewater. In the present study, magnetite nanoparticles (n-Mag) were investigated as a potential remediation technology for the decontamination of Cr (VI)-contaminated wastewater. Synthesized n-Mag was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and BET-N2 technology. To screen and optimize the factors affecting Cr (VI) removal efficiency by synthesized nanoparticles, Plackett-Burman (PB) and Taguchi experimental designs were used respectively. The crystalline produced n-Mag was in the size range of 60-70 nm and had a specific surface area (SSA) of 31.55 m(2) g(-1). Results of PB design showed that the most significant factors affecting Cr (VI) removal efficiency were initial Cr (VI) concentration, pH, n-Mag dosage, and temperature. In a pH of 2, 20 mg L(-1) of Cr (VI) concentration, 4 g L(-1)of n-Mag, temperature of 40 °C, 220 rpm of shaking speed, and 60 min of contact time, the complete removal efficiency of Cr (VI) was achieved. Batch experiments revealed that the removal of Cr (VI) by n-Mag was consistent with pseudo-second order reaction kinetics. The competition from common coexisting ions such as NO₃(-), SO₄(2-), and Cl(-) were not considerable, unless in the higher concentration of SO₄(2-). These results indicated that the readily synthesized magnetite nanoparticles have promising applications for the removal of Cr (VI) from aqueous solution.

Does multi-functionality affect technical efficiency? A non-parametric analysis of the Scottish dairy industry.

PubMed

Barnes, A P

2006-09-01

Recent policy changes within the Common Agricultural Policy have led to a shift from a solely production-led agriculture towards the promotion of multi-functionality. Conversely, the removal of production-led supports would indicate that an increased concentration on production efficiencies would seem a critical strategy for a country's future competitiveness. This paper explores the relationship between the 'multi-functional' farming attitude desired by policy makers and its effect on technical efficiency within Scottish dairy farming. Technical efficiency scores are calculated by applying the non-parametric data envelopment analysis technique and then measured against causes of inefficiency. Amongst these explanatory factors is a constructed score of multi-functionality. This research finds that, amongst other factors, a multi-functional attitude has a significant positive effect on technical efficiency. Consequently, this seems to validate the promotion of a multi-functional approach to farming currently being championed by policy-makers.

A data envelope analysis to assess factors affecting technical and economic efficiency of individual broiler breeder hens.

PubMed

Romero, L F; Zuidhof, M J; Jeffrey, S R; Naeima, A; Renema, R A; Robinson, F E

2010-08-01

This study evaluated the effect of feed allocation and energetic efficiency on technical and economic efficiency of broiler breeder hens using the data envelope analysis methodology and quantified the effect of variables affecting technical efficiency. A total of 288 Ross 708 pullets were placed in individual cages at 16 wk of age and assigned to 1 of 4 feed allocation groups. Three of them had feed allocated on a group basis with divergent BW targets: standard, high (standard x 1.1), and low (standard x 0.9). The fourth group had feed allocated on an individual bird basis following the standard BW target. Birds were classified in 3 energetic efficiency categories: low, average, and high, based on estimated maintenance requirements. Technical efficiency considered saleable chicks as output and cumulative ME intake and time as inputs. Economic efficiency of feed allocation treatments was analyzed under different cost scenarios. Birds with low feed allocation exhibited a lower technical efficiency (69.4%) than standard (72.1%), which reflected a reduced egg production rate. Feed allocation of the high treatment could have been reduced by 10% with the same chick production as the standard treatment. The low treatment exhibited reduced economic efficiency at greater capital costs, whereas high had reduced economic efficiency at greater feed costs. The average energetic efficiency hens had a lower technical efficiency in the low compared with the standard feed allocation. A 1% increment in estimated maintenance requirement changed technical efficiency by -0.23%, whereas a 1% increment in ME intake had a -0.47% effect. The negative relationship between technical efficiency and ME intake was counterbalanced by a positive correlation of ME intake and egg production. The negative relationship of technical efficiency and maintenance requirements was synergized by a negative correlation of hen maintenance and egg production. Economic efficiency methodologies are effective tools to assess the economic effect of selection and flock management programs because biological, allocative, and economic factors can be independently analyzed.

Factors influencing the ablative efficiency of high intensity focused ultrasound (HIFU) treatment for adenomyosis: A retrospective study.

PubMed

Gong, Chunmei; Yang, Bin; Shi, Yarong; Liu, Zhongqiong; Wan, Lili; Zhang, Hong; Jiang, Denghua; Zhang, Lian

2016-08-01

Objectives The aim of this study was to investigate factors affecting ablative efficiency of high intensity focused ultrasound (HIFU) for adenomyosis. Materials and methods In all, 245 patients with adenomyosis who underwent ultrasound guided HIFU (USgHIFU) were retrospectively reviewed. All patients underwent dynamic contrast-enhanced magnetic resonance imaging (MRI) before and after HIFU treatment. The non-perfused volume (NPV) ratio, energy efficiency factor (EEF) and greyscale change were set as dependent variables, while the factors possibly affecting ablation efficiency were set as independent variables. These variables were used to build multiple regression models. Results A total of 245 patients with adenomyosis successfully completed HIFU treatment. Enhancement type on T1 weighted image (WI), abdominal wall thickness, volume of adenomyotic lesion, the number of hyperintense points, location of the uterus, and location of adenomyosis all had a linear relationship with the NPV ratio. Distance from skin to the adenomyotic lesion's ventral side, enhancement type on T1WI, volume of adenomyotic lesion, abdominal wall thickness, and signal intensity on T2WI all had a linear relationship with EEF. Location of the uterus and abdominal wall thickness also both had a linear relationship with greyscale change. Conclusion The enhancement type on T1WI, signal intensity on T2WI, volume of adenomyosis, location of the uterus and adenomyosis, number of hyperintense points, abdominal wall thickness, and distance from the skin to the adenomyotic lesion's ventral side can all be used as predictors of HIFU for adenomyosis.

Communication in cancer care: psycho-social, interactional, and cultural issues. A general overview and the example of India.

PubMed

Chaturvedi, Santosh K; Strohschein, Fay J; Saraf, Gayatri; Loiselle, Carmen G

2014-01-01

Communication is a core aspect of psycho-oncology care. This article examines key psychosocial, cultural, and technological factors that affect this communication. Drawing from advances in clinical work and accumulating bodies of empirical evidence, the authors identify determining factors for high quality, efficient, and sensitive communication and support for those affected by cancer. Cancer care in India is highlighted as a salient example. Cultural factors affecting cancer communication in India include beliefs about health and illness, societal values, integration of spiritual care, family roles, and expectations concerning disclosure of cancer information, and rituals around death and dying. The rapidly emerging area of e-health significantly impacts cancer communication and support globally. In view of current globalization, understanding these multidimensional psychosocial, and cultural factors that shape communication are essential for providing comprehensive, appropriate, and sensitive cancer care.

Evaluation of the Timing Properties of a High Quantum Efficiency Photomultiplier Tube

NASA Astrophysics Data System (ADS)

Peng, Qiyu; Choong, Woon-Seng; Moses, W. William

2013-10-01

We measured the timing resolution of 189 R9800-100 photomultiplier tubes (PMTs), which are a SBA (Super Bialkali, high quantum efficiency) variant of the R9800 high-performance PMT manufactured by Hamamatsu Photonics, and correlated their timing resolutions with various measures of PMT performance, namely Cathode Luminous Sensitivity (CLS), Anode Luminous Sensitivity (ALS), Gain times Collection Efficiency (GCE), Cathode Blue Sensitivity Index (CBSI), Anode Blue Sensitivity Index (ABSI) and dark current. The correlation results show: (1) strong correlations between timing resolution and ALS, ABSI, and GCE; (2) moderate correlations between timing resolution and CBSI; and (3) weak or no correlations between timing resolution and dark current and CLS. The results disclosed that all three measures that include data collected from the anode (ALS, ABSI, and GCE) affect the timing resolution more than either of the two measures that only include photocathode data (CBSI and CLS). We conclude that: (1) the photocathode Quantum Efficiency (QE) and the product of the Gain and the Collection Efficiency (GCE) are the two dominant factors that affect the timing resolution, (2) the GCE variation affects the timing resolution more than the QE variation in the R9800 PMT, and (3) the performance depends on photocathode position.

Factors affecting energy and nitrogen efficiency of dairy cows: a meta-analysis.

PubMed

Phuong, H N; Friggens, N C; de Boer, I J M; Schmidely, P

2013-01-01

A meta-analysis was performed to explore the correlation between energy and nitrogen efficiency of dairy cows, and to study nutritional and animal factors that influence these efficiencies, as well as their relationship. Treatment mean values were extracted from 68 peer-reviewed studies, including 306 feeding trials. The main criterion for inclusion of a study in the meta-analysis was that it reported, or permitted calculation of, energy efficiency (Eeff; energy in milk/digestible energy intake) and nitrogen efficiency (Neff; nitrogen in milk/digestible nitrogen intake) at the digestible level (digestible energy or digestible protein). The effect of nutritional and animal variables, including neutral detergent fiber, acid detergent fiber (ADF), digestible energy, digestible protein, proportion of concentrate (PCO), dry matter intake, milk yield, days in milk, and body weight, on Eeff, Neff, and the Neff:Eeff ratio was analyzed using mixed models. The interstudy correlation between Eeff and Neff was 0.62, whereas the intrastudy correlation was 0.30. The higher interstudy correlation was partly due to milk yield and dry matter intake being present in both Eeff and Neff. We, therefore, also explored the Neff:Eeff ratio. Energy efficiency was negatively associated with ADF and PCO, whereas Neff was negatively associated with ADF and digestible energy. The Neff:Eeff ratio was affected by ADF and PCO only. In conclusion, the results indicate a possibility to maximize feed efficiency in terms of both energy and nitrogen at the same time. In other words, an improvement in Eeff would also mean an improvement in Neff. The current study also shows that these types of transverse data are not sufficient to study the effect of animal factors, such as days in milk, on feed efficiency. Longitudinal measurements per animal would probably be more appropriate. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Factors influencing foraging search efficiency: why do scarce lappet-faced vultures outperform ubiquitous white-backed vultures?

PubMed

Spiegel, Orr; Getz, Wayne M; Nathan, Ran

2013-05-01

The search phase is a critical component of foraging behavior, affecting interspecific competition and community dynamics. Nevertheless, factors determining interspecific variation in search efficiency are still poorly understood. We studied differences in search efficiency between the lappet-faced vulture (Torgos tracheliotus; LFV) and the white-backed vulture (Gyps africanus; WBV) foraging on spatiotemporally unpredictable carcasses in Etosha National Park, Namibia. We used experimental food supply and high-resolution GPS tracking of free-ranging vultures to quantify search efficiency and elucidate the factors underlying the observed interspecific differences using a biased correlated random walk simulation model bootstrapped with the GPS tracking data. We found that LFV's search efficiency was higher than WBV's in both first-to-find, first-to-land, and per-individual-finding rate measures. Modifying species-specific traits in the simulation model allows us to assess the relative role of each factor in LFV's higher efficiency. Interspecific differences in morphology (through the effect on perceptual range and motion ability) and searchers' spatial dispersion (due to different roost arrangements) are in correspondence with the empirically observed advantage of LFV over WBV searchers, whereas differences in other aspects of the movement patterns appear to play a minor role. Our results provide mechanistic explanations for interspecific variation in search efficiency for species using similar resources and foraging modes.

Factors Affecting Survival of Longleaf Pine Seedlings

Treesearch

John S. Kush; Ralph S. Meldahl; William D. Boyer

2004-01-01

Longleaf pine may be managed most efficiently in large even-aged stands. Past research has shown that the effect of trees surrounding the openings (gaps) or the use of fire is a complicating factor, especially with small openings. Longleaf seedlings are considered more susceptible to fire under and nearer to standing trees, and seedling size, kind of fire, soil type,...

EV Charging Through Wireless Power Transfer: Analysis of Efficiency Optimization and Technology Trends

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, John M; Rakouth, Heri; Suh, In-Soo

This paper is aimed at reviewing the technology trends for wireless power transfer (WPT) for electric vehicles (EV). It also analyzes the factors affecting its efficiency and describes the techniques currently used for its optimization. The review of the technology trends encompasses both stationary and moving vehicle charging systems. The study of the stationary vehicle charging technology is based on current implementations and on-going developments at WiTricity and Oak Ridge National Lab (ORNL). The moving vehicle charging technology is primarily described through the results achieved by the Korean Advanced Institute of Technology (KAIST) along with on-going efforts at Stanford University.more » The factors affecting the efficiency are determined through the analysis of the equivalent circuit of magnetic resonant coupling. The air gap between both transmitting and receiving coils along with the magnetic field distribution and the relative impedance mismatch between the related circuits are the primary factors affecting the WPT efficiency. Currently the industry is looking at an air gap of 25 cm or below. To control the magnetic field distribution, Kaist has recently developed the Shaped Magnetic Field In Resonance (SMFIR) technology that uses conveniently shaped ferrite material to provide low reluctance path. The efficiency can be further increased by means of impedance matching. As a result, Delphi's implementation of the WiTricity's technology exhibits a WPT efficiency above 90% for stationary charging while KAIST has demonstrated a maximum efficiency of 83% for moving vehicle with its On Line Vehicle (OLEV) project. This study is restricted to near-field applications (short and mid-range) and does not address long-range technology such as microwave power transfer that has low efficiency as it is based on radiating electromagnetic waves. This paper exemplifies Delphi's work in powertrain electrification as part of its innovation for the real world program geared toward a safer, greener and more connected driving. Moreover, it draws from and adds to Dr. Andrew Brown Jr.'s SAE books 'Active Safety and the Mobility Industry', 'Connectivity and Mobility Industry', and 'Green Technologies and the Mobility Industry'. Magnetic resonant coupling is the foundation of modern wireless power transfer. Its efficiency can be controlled through impedance matching and magnetic field shaping. Current implementations use one or both of these control methods and enable both stationary and mobile charging with typical efficiency within the 80% and 90% range for an air gap up to 25 cm.« less

Pump/Control System Minimum Operating Cost Testing

NASA Technical Reports Server (NTRS)

1977-01-01

A preliminary evaluation of pump performance was initiated to determine the efficiencies of an arbitrary group of small pumps. Trends in factors affecting energy usage in typical prime movers which might be used in liquid transport solar systems were assessed. Comparisons of centrifugal pump efficiencies were made from one manufacturer to another. Tests were also made on two positive-displacement pumps and comparisons with centrifugal pumps were observed.

Collection efficiency of a single optical fiber in turbid media.

PubMed

Bargo, Paulo R; Prahl, Scott A; Jacques, Steven L

2003-06-01

If a single optical fiber is used for both delivery and collection of light, two major factors affect the measurement of collected light: (1) the light transport in the medium that describes the amount of light that returns to the fiber and (2) the light coupling to the optical fiber that depends on the angular distribution of photons entering the fiber. We focus on the importance of the latter factor and describe how the efficiency of the coupling depends on the optical properties of the medium. For highly scattering tissues, the efficiency is well predicted by the numerical aperture (NA) of the fiber. For lower scattering, such as in soft tissues, photons arrive at the fiber from deeper depths, and the coupling efficiency could increase twofold to threefold above that predicted by the NA.

Design, processing and testing of LSI arrays hybrid microelectronics task

NASA Technical Reports Server (NTRS)

Himmel, R. P.; Stuhlbarg, S. M.; Salmassy, S.

1978-01-01

Those factors affecting the cost of electronic subsystems utilizing LSI microcircuits were determined and the most efficient methods for low cost packaging of LSI devices as a function of density and reliability were developed.

Factors Affecting the Corporate Decision-Making Process of Air Transport Manufacturers

NASA Technical Reports Server (NTRS)

Ollila, R. G.; Hill, J. D.; Noton, B. R.; Duffy, M. A.; Epstein, M. M.

1976-01-01

Fuel economy is a pivotal question influencing the future sale and utilization of commercial aircraft. The NASA Aircraft Energy Efficiency (ACEE) Program Office has a program intended to accelerate the readiness of advanced technologies for energy efficient aircraft. Because the decision to develop a new airframe or engine is a major financial hazard for manufacturers, it is important to know what factors influence the decision making process. A method is described for identifying and ranking individuals and organizations involved at each stage of commercial air transport development, and the barriers that must be overcome in adopting new technologies.

Human Factors and Their Effects on Human-Centred Assembly Systems - A Literature Review-Based Study

NASA Astrophysics Data System (ADS)

Wang, Q.; Abubakar, M. I.

2017-09-01

If a product has more than one component, then it must be assembled. Assembly of products relies on assembly systems or lines in which assembly of each product is often carried out manually by human workers following assembly sequences in various forms. It is widely understood that efficiency of assembling a product by reducing assembly times (therefore costs) is vital particularly for small and medium-sized manufacturing companies to survive in an increasingly competitive market. Ideally, it is helpful for pre-determining efficiency or productivity of a human-centred assembly system at the early design stage. To date, most research on performance of an assembly system using modelling simulation methods is focused on its “operational functions”. The term used in a narrow sense always indicates the performance of the “operational system”, which does not incorporate the effect of human factors that may also affect the system performance. This paper presents a research outcome of findings through a literature review-based study by identifying possible human factors that mostly affect the performance on human-centred manufacturing systems as part of the research project incorporating parameters of human factors into a DES (discrete event simulation) tool.

Passing the Bubble: Cognitive Efficiency of Augmented Video for Collaborative Transfer of Situational Understanding

DTIC Science & Technology

2003-01-01

media factors affecting: • Shared Understanding – explicit and operational knowledge • Decision-Making – what information format best helps decision...Passing the Bubble: Cognitive Efficiency of Augmented Video for Collaborative Transfer of Situational Understanding Collaboration and Knowledge ...operational knowledge ? • Informed Decision-Making – what information format is best to pass the bubble to a decision-maker 1/14/2003 ONR David Kirsh

Factors Affecting Aerosol Radiative Forcing from Both Production-based and Consumption-based View

NASA Astrophysics Data System (ADS)

Wang, J.; Lin, J.; Ni, R.

2017-12-01

Aerosol radiative forcing (RF) is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. This problem becomes more complicated when taking into account the role of international trade, which means reallocated aerosol RF due to separation of regions producing goods and emissions and regions consuming those goods. Here we analyze major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA) and black carbon (BC), extending the work of Lin et al. (2016, Nature Geoscience). We contrast five factors determining production-based (RFp, due to a region's production of goods) and consumption-based (RFc, due to a region's consumption) forcing by 11 major regions, including population size, per capita output, emission intensity (emission per output), chemical efficiency (mass per unit emission) and radiative efficiency (RF per unit mass). Comparing across the 11 regions, East Asia produces the strongest RFp and RFc of SIOA and BC and the second largest RFp and RFc of POA primarily due to its high emission intensity. Although Middle East and North Africa has low emissions, its RFp is strengthened by its largest chemical efficiency for POA and BC and second largest chemical efficiency for SIOA. However, RFp of South-East Asia and Pacific is greatly weakened by its lowest chemical efficiency. Economic trade means that net importers (Western Europe, North America and Pacific OECD) have higher RFc than RFp by 50-100%. And such forcing difference is mainly due to the high emission intensity of the exporters supplying these regions. For North America, SIOA's RFc is 50% stronger than RFp, for that emission intensity of SIOA is 5.2 times in East Asia and 2.5 times in Latin America and Caribbean compared with that in North America, and the chemical efficiency in the top four exporters are 1.4-2.1 times of North America. For East Asia, the RFc of SIOA is 20% lower than RFp due to the relatively low emission intensity and chemical efficiency of the top two exporters (Pacific OECD and Western Europe). Overall, economic, emission and atmospheric factors all play important roles in differentiating regions' RFp and RFc.

Organizational commitment and job satisfaction among nurses in Serbia: a factor analysis.

PubMed

Veličković, Vladica M; Višnjić, Aleksandar; Jović, Slađana; Radulović, Olivera; Šargić, Čedomir; Mihajlović, Jovan; Mladenović, Jelena

2014-01-01

One of the basic prerequisites of efficient organizational management in health institutions is certainly monitoring and measuring satisfaction of employees and their commitment to the health institution in which they work. The aim of this article was to identify and test factors that may have a predictive effect on job satisfaction and organizational commitment. We conducted a cross-sectional study that included 1,337 nurses from Serbia. Data were analyzed by using exploratory factor analysis, multivariate regressions, and descriptive statistics. The study identified three major factors of organizational commitment: affective commitment, disloyalty, and continuance commitment. The most important predictors of these factors were positive professional identification, extrinsic job satisfaction, and intrinsic job satisfaction (p < .0001). Predictors significantly affecting both job satisfaction and organizational commitment were identified as well; the most important of which was positive professional identification (p < .0001). This study identified the main factors affecting job satisfaction and organizational commitment of nurses, which formed a good basis for the creation of organizational management policy and human resource management policy in health institutions in Serbia. Copyright © 2014 Elsevier Inc. All rights reserved.

Supernovae Discovery Efficiency

NASA Astrophysics Data System (ADS)

John, Colin

2018-01-01

Abstract:We present supernovae (SN) search efficiency measurements for recent Hubble Space Telescope (HST) surveys. Efficiency is a key component to any search, and is important parameter as a correction factor for SN rates. To achieve an accurate value for efficiency, many supernovae need to be discoverable in surveys. This cannot be achieved from real SN only, due to their scarcity, so fake SN are planted. These fake supernovae—with a goal of realism in mind—yield an understanding of efficiency based on position related to other celestial objects, and brightness. To improve realism, we built a more accurate model of supernovae using a point-spread function. The next improvement to realism is planting these objects close to galaxies and of various parameters of brightness, magnitude, local galactic brightness and redshift. Once these are planted, a very accurate SN is visible and discoverable by the searcher. It is very important to find factors that affect this discovery efficiency. Exploring the factors that effect detection yields a more accurate correction factor. Further inquires into efficiency give us a better understanding of image processing, searching techniques and survey strategies, and result in an overall higher likelihood to find these events in future surveys with Hubble, James Webb, and WFIRST telescopes. After efficiency is discovered and refined with many unique surveys, it factors into measurements of SN rates versus redshift. By comparing SN rates vs redshift against the star formation rate we can test models to determine how long star systems take from the point of inception to explosion (delay time distribution). This delay time distribution is compared to SN progenitors models to get an accurate idea of what these stars were like before their deaths.

Allocative Efficiency Analysys Production Function Of Cassava Farming (Manihot, Sp.) In Tenayan Raya Sub-District Of Pekanbaru City

NASA Astrophysics Data System (ADS)

Nizar, Rini; Nurwati, Niken; Amalia

2017-12-01

Cassava (Manihot sp) has long been known and cultivated by Indonesian farmers. The economic and social potential of cassava aside from foodstuffs can also be used as raw materials for industrial use and animal feed. In Riau Province, Cassva has the potential to be developed considering Cassva is a plant that can easily grow on low altitude to high altitude lands. Cassava does not need a complex maintenance. Conventionally, this plant can be planted and left alone by itself. Cassava roots can be developed to be a processed products that society needs as main foodstuffs ingredients. This research is done in three months and the purpose is to know the influence of input use (pesticide, seeds, fertilizers and labor) on cassava farming to cassava farming by the model of cobb-douglas. Other than that is also the effect on economical efficiency. The method used in this research is a quantitative research by using Cobb-Douglas Function Model. This research was done in the Tenayan Raya sub-district with 55 farmer samples. This research shows Cobb-Douglas Production Function can be used as the predictor for Cassava production function in Tenayan Raya Sub-district of Pekanbaru City. Altogether the production factor used by farmers influence production. Partially only usage of organic fertilizer that does not affect production, while other production factor such as, seeds, pesticides, an-organic fertilizer (urea) and labor affect production by quite a bit. Usage of production factor seeds, urea and pesticides is not yet efficient while usage of organic fertilizer is not efficient and usage of labor on cassava agriculture by respondent farmers is relatively efficient

Liquid Chromatography in 1982.

ERIC Educational Resources Information Center

Freeman, David H.

1982-01-01

Reviews trends in liquid chromatography including apparatus, factors affecting efficient separation of a mixture (peak sharpness and speed), simplified problem-solving, adsorption, bonded phase chromatography, ion selectivity, and size exclusion. The current trend is to control chemical selectivity by the liquid phase. (Author/JN)

NHTS brief : energy use and fuel efficiency

DOT National Transportation Integrated Search

2008-04-01

A number of factors affect fuel consumption in the U.S., such as total driving population and annual vehicle miles of travel per driver. According the National Household Travel Survey (NHTS) data series, both of these have nearly doubled since 1969.

Deciphering the Environmental Impacts on Rice Quality for Different Rice Cultivated Areas.

PubMed

Li, Xiukun; Wu, Lian; Geng, Xin; Xia, Xiuhong; Wang, Xuhong; Xu, Zhengjin; Xu, Quan

2018-01-19

Rice (Oryza sativa L.) is cultivated in a wide range of climatic conditions, and is one of mankind's major staple foods. The interaction of environmental factors with genotype effects major agronomic traits such as yield, quality, and resistance in rice. However, studies on the environmental factors affecting agronomic traits are often difficult to conduct because most environmental factors are dynamic and constantly changing. A series of recombinant inbred lines (RILs) derived from an indica/japonica cross were planted into four typical rice cultivated areas arranging from latitude N22° to N42°. The environmental data from the heading to mature (45 days) stages were recorded for each RIL in the four areas. We determined that light, temperature, and humidity significantly affected the milling quality and cooking quality overall the four areas. Within each area, these environmental factors mainly affected the head rice ratio, grain length, alkali consumption, and amylose and protein content. Moreover, the effect of these environmental factors dynamically changed from heading to mature stage. Compared to light and humidity, temperature was more stable and predictable, and night temperature showed a stronger correlation efficiency to cooking quality than day temperature, and the daily temperature range had contrary effects compared to day and night temperature on grain quality. The present study evaluated the critical phase during the grain filling stage by calculating the dynamic changes of correlation efficiency between the quality traits and climate parameters. Our findings suggest that the sowing date could be adjusted to improve rice quality so as to adjust for environmental changes.

Techno-economical efficiency and productivity change of wastewater treatment plants: the role of internal and external factors.

PubMed

Hernández-Sancho, F; Molinos-Senante, M; Sala-Garrido, R

2011-12-01

Efficiency and productivity are important measures for identifying best practice in businesses and optimising resource-use. This study analyses how these two measures change across the period 2003-2008 for 196 wastewater treatment plants (WWTPs) in Spain, by using the benchmarking methods of Data Envelopment Analysis and the Malmquist Productivity Index. To identify which variables contribute to the sustainability of the WWTPs, differences in efficiency scores and productivity indices for external factors are also investigated. Our results indicate that both efficiency and productivity decreased over the five years. We verify that the productivity drop is primarily explained by technical change. Furthermore, certain external variables affected WWTP efficiency, including plant size, treatment technology and energy consumption. However, plants with low energy consumption are the only ones which improve their productivity. Finally, the benchmarking analyses proved to be useful as management tools in the wastewater sector, by providing vital information for improving the sustainability of plants.

Factors concerned in the efficient steam sterilization of surgical dressings

PubMed Central

Fallon, R. J.

1961-01-01

Some of the factors affecting the efficient steam sterilization of dressings have been examined. A jacketed sterilizer will process a load more quickly than a sterilizer without a jacket. The level of fore-vacuum is critical and must reach an absolute pressure of 20 mm. Hg (29·2 in.Hg vacuum) or less. This will overcome all conditions of overpacking studied. The level of after-vacuum should be 100 mm. Hg absolute or less, preferably near 50 mm. Hg absolute. Overpacking cannot be defined in terms of weight of a fabric per unit volume of container but occurs when a load is compressed in its container. PMID:13891475

Joint and National Intelligence Support to Military Operations

DTIC Science & Technology

2004-10-07

missions. The goal is to maximize the impact of intelligence on military operations by increasing the efficiency of the intelligence process and the...intelligence support to military operations will be affected by non-threat-related environmental factors such as requisite changes in sources and...tailored and highly detailed intelligence analyses of a wide variety of human and information environmental factors, such as public attitudes and

Genome-wide RNAi screening identifies host restriction factors critical for in vivo AAV transduction

PubMed Central

Mano, Miguel; Ippodrino, Rudy; Zentilin, Lorena; Zacchigna, Serena; Giacca, Mauro

2015-01-01

Viral vectors based on the adeno-associated virus (AAV) hold great promise for in vivo gene transfer; several unknowns, however, still limit the vectors’ broader and more efficient application. Here, we report the results of a high-throughput, whole-genome siRNA screening aimed at identifying cellular factors regulating AAV transduction. We identified 1,483 genes affecting vector efficiency more than 4-fold and up to 50-fold, either negatively or positively. Most of these factors have not previously been associated to AAV infection. The most effective siRNAs were independent from the virus serotype or analyzed cell type and were equally evident for single-stranded and self-complementary AAV vectors. A common characteristic of the most effective siRNAs was the induction of cellular DNA damage and activation of a cell cycle checkpoint. This information can be exploited for the development of more efficient AAV-based gene delivery procedures. Administration of the most effective siRNAs identified by the screening to the liver significantly improved in vivo AAV transduction efficiency. PMID:26305933

Detailed Balance Limit of Efficiency of Broadband-Pumped Lasers.

PubMed

Nechayev, Sergey; Rotschild, Carmel

2017-09-13

Broadband light sources are a wide class of pumping schemes for lasers including LEDs, sunlight and flash lamps. Recently, efficient coupling of broadband light to high-quality micro-cavities has been demonstrated for on-chip applications and low-threshold solar-pumped lasers via cascade energy transfer. However, the conversion of incoherent to coherent light comes with an inherent price of reduced efficiency, which has yet to be assessed. In this paper, we derive the detailed balance limit of efficiency of broadband-pumped lasers and discuss how it is affected by the need to maintain a threshold population inversion and thermodynamically dictated minimal Stokes' shift. We show that lasers' slope efficiency is analogous to the nominal efficiency of solar cells, limited by thermalisation losses and additional unavoidable Stokes' shift. The lasers' power efficiency is analogous to the detailed balance limit of efficiency of solar cells, affected by the cavity mirrors and impedance matching factor, respectively. As an example we analyze the specific case of solar-pumped sensitized Nd 3+ :YAG-like lasers and define the conditions to reach their thermodynamic limit of efficiency. Our work establishes an upper theoretical limit for the efficiency of broadband-pumped lasers. Our general, yet flexible model also provides a way to incorporate other optical and thermodynamic losses and, hence, to estimate the efficiency of non-ideal broadband-pumped lasers.

CHARACTERIZATION OF VIRAL RNA EXTRACTION EFFICIENCY FROM ENVIRONMENTAL WATERS

EPA Science Inventory

Inhibition of PCR by environmental factors is a common problem affecting the sensitive detection of pathogenic microorganisms in environmental waters. This inhibition is caused by one of three mechanisms: 1) failure to lyse the microorganism, 2) degradation or sequestering of the...

20 CFR 405.317 - Objections.

Code of Federal Regulations, 2010 CFR

2010-04-01

...' Benefits SOCIAL SECURITY ADMINISTRATION ADMINISTRATIVE REVIEW PROCESS FOR ADJUDICATING INITIAL DISABILITY... requesting the change and the impact of the proposed change on the efficient administration of the hearing process. Factors affecting the impact of the change include, but are not limited to, the effect on the...

Measuring and explaining multi-directional inefficiency in the Malaysian dairy industry.

PubMed

Mohd Suhaimi, Nurul Aisyah Binti; de Mey, Yann; Oude Lansink, Alfons

2017-01-01

The purpose of this paper is to measure the technical inefficiency of dairy farms and subsequently investigate the factors affecting technical inefficiency in the Malaysian dairy industry. This study uses multi-directional efficiency analysis to measure the technical inefficiency scores on a sample of 200 farm observations and single-bootstrap truncated regression model to define factors affecting technical inefficiency. Managerial and program inefficiency scores are presented for intensive and semi-intensive production systems. The results reveal marked differences in the inefficiency scores across inputs and between production systems. Intensive systems generally have lowest managerial and program inefficiency scores in the Malaysian dairy farming sector. Policy makers could use this information to advise dairy farmers to convert their farming system to the intensive system. The results suggest that the Malaysian Government should redefine its policy for providing farm finance and should target young farmers when designing training and extension programs in order to improve the performance of the dairy sector. The existing literature on Southeast Asian dairy farming has neither focused on investigating input-specific efficiency nor on comparing managerial and program efficiency. This paper aims to fill this gap.

Factors Affecting Aerosol Radiative Forcing

NASA Astrophysics Data System (ADS)

Wang, Jingxu; Lin, Jintai; Ni, Ruijing

2016-04-01

Rapid industrial and economic growth has meant a large amount of aerosols in the atmosphere with strong radiative forcing (RF) upon the climate system. Over parts of the globe, the negative forcing of aerosols has overcompensated for the positive forcing of greenhouse gases. Aerosol RF is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. In this study, we analyze the major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA), and black carbon (BC). We analyze the RF of aerosols produced by 11 major regions across the globe, including but not limited to East Asia, Southeast Asia, South Asia, North America, and Western Europe. Factors analyzed include population size, per capita gross domestic production (GDP), emission intensity (i.e., emissions per unit GDP), chemical efficiency (i.e., mass per unit emissions) and radiative efficiency (i.e., RF per unit mass). We find that among the 11 regions, East Asia produces the largest emissions and aerosol RF, due to relatively high emission intensity and a tremendous population size. South Asia produce the second largest RF of SIOA and BC and the highest RF of POA, in part due to its highest chemical efficiency among all regions. Although Southeast Asia also has large emissions, its aerosol RF is alleviated by its lowest chemical efficiency. The chemical efficiency and radiative efficiency of BC produced by the Middle East-North Africa are the highest across the regions, whereas its RF is lowered by a small per capita GDP. Both North America and Western Europe have low emission intensity, compensating for the effects on RF of large population sizes and per capita GDP. There has been a momentum to transfer industries to Southeast Asia and South Asia, and such transition is expected to continue in the coming years. The resulting relocation of emissions would meant drastic changes in both the spatial distribution and the magnitude of RF, with consequences on regional and global climate forcing. Our findings are relevant to global aerosol control and climate mitigation.

Factors Affecting Aerosol Radiative Forcing

NASA Astrophysics Data System (ADS)

Wang, J.; Lin, J.; Ni, R.

2016-12-01

Rapid industrial and economic growth has meant large amount of aerosols in the atmosphere with strong radiative forcing (RF) upon the climate system. Over parts of the globe, the negative forcing of aerosols has overcompensated for the positive forcing of greenhouse gases. Aerosol RF is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. In this study, we analyze the major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA), and black carbon (BC). We analyze the RFof aerosols produced by 11 major regions across the globe, including but not limited to East Asia, Southeast Asia, South Asia, North America, and Western Europe. Factors analyzed include population size, per capita gross domestic production (GDP), emission intensity (i.e., emissionsper unit GDP), chemical efficiency (i.e., mass per unit emissions) and radiative efficiency (i.e., RF per unit mass). We find that among the 11 regions, East Asia produces the largest emissions and aerosol RF, due to relatively high emission intensity and a tremendous population size.South Asia produce the second largest RF of SIOA and BC and the highest RF of POA, in part due to its highest chemical efficiency among all regions. Although Southeast Asia also has large emissions,its aerosol RF is alleviated by its lowest chemical efficiency.The chemical efficiency and radiative efficiency of BC produced by the Middle East-North Africa are the highest across the regions, whereas its RF is loweredbyasmall per capita GDP.Both North America and Western Europe have low emission intensity, compensating for the effects on RF of large population sizes and per capita GDP. There has been a momentum to transfer industries to Southeast Asia and South Asia, and such transition is expected to continue in the coming years. The resulting relocation of emissions would meant drastic changes in both the spatial distribution and the magnitude of RF, with consequences on regional and global climate forcing. Our findings are relevant to global aerosol control and climate mitigation.

Factors affecting sustainable dairy production: A case study from Uva Province of Sri Lanka

NASA Astrophysics Data System (ADS)

Wijethilaka, D.; De Silva, S.; Deshapriya, R. M. C.; Gunaratne, L. H. P.

2018-05-01

Dairy farming has been playing a key role by improving household incomes and food security for rural communities in Sri Lanka. Nevertheless, it has failed to meet the expected self-sufficiency. In 2015, Sri Lanka imported 51percent of the national milk requirement spending US 251 million from its debt-ridden economy. This paper aims to analyse socio-economic characteristics of dairy farmers and factors affecting dairy production efficiency in the Uva Province of Sri Lanka, a highly potential area comprising all the dairy value chain actors. Surveyed was conducted to farmers, key informants from input suppliers, collectors, transporters, processors, sellers and support service providers. Result revealed that intensive farmer’s milk yields per cow was only 7.97 L/day, which was 35% and 60% higher than the yields of semi-intensive and extensive farmers respectively. The highest profit of Rs. 53.30 per litre was earned by extensive farmers, whereas it was Rs. 47.63 for semi-intensive and Rs. 44.76 for intensive farmers respectively if family labour cost was not taken into the account. The Technical Efficiency Analysis revealed that 37.1% and 20% milk production of intensive farmers and semi-intensive is being loss due to inefficiency and could be increased without any additional inputs. The main factors affecting efficiency in milk production included farmers’ socio-economic characteristics and farm characteristics. Based on the results it can be concluded that sustainability dairy production depends on farmer training, collectivizing farmers into farmer societies, culling unproductive male animals, increasing the availability and access to AI/other breading programs and low-cost quality concentrate feed and other supplements, and, thus appropriate measures should be taken to provide these conditions if Sri Lanka aims to achieve self-sufficiency in milk production.

Ecological efficiency in China and its influencing factors-a super-efficient SBM metafrontier-Malmquist-Tobit model study.

PubMed

Ma, Xiaojun; Wang, Changxin; Yu, Yuanbo; Li, Yudong; Dong, Biying; Zhang, Xinyu; Niu, Xueqi; Yang, Qian; Chen, Ruimin; Li, Yifan; Gu, Yihan

2018-05-15

Ecological problem is one of the core issues that restrain China's economic development at present, and it is urgently needed to be solved properly and effectively. Based on panel data from 30 regions, this paper uses a super efficiency slack-based measure (SBM) model that introduces the undesirable output to calculate the ecological efficiency, and then uses traditional and metafrontier-Malmquist index method to study regional change trends and technology gap ratios (TGRs). Finally, the Tobit regression and principal component analysis methods are used to analysis the main factors affecting eco-efficiency and impact degree. The results show that about 60% of China's provinces have effective eco-efficiency, and the overall ecological efficiency of China is at the superior middling level, but there is a serious imbalance among different provinces and regions. Ecological efficiency has an obvious spatial cluster effect. There are differences among regional TGR values. Most regions show a downward trend and the phenomenon of focusing on economic development at the expense of ecological protection still exists. Expansion of opening to the outside, increases in R&D spending, and improvement of population urbanization rate have positive effects on eco-efficiency. Blind economic expansion, increases of industrial structure, and proportion of energy consumption have negative effects on eco-efficiency.

The physiology and biomechanics of competitive swimming.

PubMed

Troup, J P

1999-04-01

Fast swimming, either in the pool, in open water swimming, or in water polo and synchronized swimming, requires maximizing the efficiencies with which the human body can move through a liquid medium. A multitude of factors can affect the ability to swim fast as well as the final outcome. Physiology and biomechanics are the present tools used by sports scientists to determine which factors are important to fast swimming and, subsequently, to determine how the swimmer may maximize these factors to improve performance.

Model and Study on Cascade Control System Based on IGBT Chopping Control

NASA Astrophysics Data System (ADS)

Niu, Yuxin; Chen, Liangqiao; Wang, Shuwen

2018-01-01

Thyristor cascade control system has a wide range of applications in the industrial field, but the traditional cascade control system has some shortcomings, such as a low power factor, serious harmonic pollution. In this paper, not only analyzing its system structure and working principle, but also discussing the two main factors affecting the power factor. Chopping-control cascade control system, adopted a new power switching device IGBT, which could overcome traditional cascade control system’s two main drawbacks efficiently. The basic principle of this cascade control system is discussed in this paper and the model of speed control system is built by using MATLAB/Simulink software. Finally, the simulation results of the system shows that the system works efficiently. This system is worthy to be spread widely in engineering application.

DNA Microarrays for Aptamer Identification and Structural Characterization

DTIC Science & Technology

2012-09-01

appropriate vector (which has a unique set of factors affecting cloning efficiency) and transformed into competent bacterial cells to spatially...818-822. 2) Tuerk, C. and Gold, L., “Systematic Evolution of Ligands by Exponential Enrichment: RNA Ligands to Bacteriophage T4 DNA Polymerase

Won’t soil be damaged if cattle graze cover crops?

USDA-ARS?s Scientific Manuscript database

Integration of crops and livestock could provide economic benefits to producers by intensifying land use and improving resource efficiency, but how this management might affect soil compaction, water infiltration, and soil strength has not been well documented. Key factors in balancing cattle produ...

Recovery of high-purity metallic Pd from Pd(II)-sorbed biosorbents by incineration.

PubMed

Won, Sung Wook; Lim, Areum; Yun, Yeoung-Sang

2013-06-01

This work reports a direct way to recover metallic palladium with high purity from Pd(II)-sorbed polyethylenimine-modified Corynebacterium glutamicum biosorbent using a combined method of biosorption and incineration. This study is focused on the incineration part which affects the purity of recovered Pd. The incineration temperature and the amount of Pd loaded on the biosorbent were considered as major factors in the incineration process, and their effects were examined. The results showed that both factors significantly affected the enhancement of the recovery efficiency and purity of the recovered Pd. SEM-EDX and XRD analyses were used to confirm that Pd phase existed in the ash. As a result, the recovered Pd was changed from PdO to zero-valent Pd as the incineration temperature was increased from 600 to 900°C. Almost 100% pure metallic Pd was recovered with recovery efficiency above 99.0% under the conditions of 900°C and 136.9 mg/g. Copyright © 2013 Elsevier Ltd. All rights reserved.

High hydrostatic pressure inactivation of Lactobacillus plantarum cells in (O/W)-emulsions is independent from cell surface hydrophobicity and lipid phase parameters

NASA Astrophysics Data System (ADS)

Kafka, T. A.; Reitermayer, D.; Lenz, C. A.; Vogel, R. F.

2017-07-01

Inactivation efficiency of high hydrostatic pressure (HHP) processing of food is strongly affected by food matrix composition. We investigated effects of fat on HHP inactivation of spoilage-associated Lactobacillus (L.) plantarum strains using defined oil-in-water (O/W)-emulsion model systems. Since fat-mediated effects on HHP inactivation could be dependent on interactions between lipid phase and microbial cells, three major factors possibly influencing such interactions were considered, that is, cell surface hydrophobicity, presence and type of surfactants, and oil droplet size. Pressure tolerance varied noticeably among L. plantarum strains and was independent of cell surface hydrophobicity. We showed that HHP inactivation of all strains tended to be more effective in presence of fat. The observation in both, surfactant-stabilized and surfactant-free (O/W)-emulsion, indicates that cell surface hydrophobicity is no intrinsic pressure resistance factor. In contrast to the presence of fat per se, surfactant type and oil droplet size did not affect inactivation efficiency.

Factors influencing Agrobacterium-mediated embryogenic callus transformation of Valencia sweet orange (Citrus sinensis) containing the pTA29-barnase gene.

PubMed

Li, D D; Shi, W; Deng, X X

2003-12-01

Valencia sweet orange (Citrus sinensis (L.) Osbeck) calluses were used as explants to develop a new transformation system for citrus mediated by Agrobacterium tumefaciens. Factors affecting Agrobacterium-mediated transformation efficiency included mode of pre-cultivation, temperature of cocultivation and presence of acetosyringone (AS). The highest transformation efficiency was obtained with a 4-day pre-cultivation period in liquid medium. Transformation efficiency was higher when cocultivation was performed for 3 days at 19 degrees C than at 23 or 28 degrees C. Almost no resistant callus was obtained if the cocultivation medium lacked AS. The transformation procedure yielded transgenic Valencia plants containing the pTA29-barnase gene, as verified by PCR amplification and confirmed by Southern blotting. Because male sterility is a common factor leading to seedlessness in citrus cultivars with parthenocarpic characteristics, production of seedless citrus genotypes by Agrobacterium-mediated genetic transformation is a promising alternative to conventional breeding methods.

Differential translation efficiency of orthologous genes is involved in phenotypic divergence of yeast species.

PubMed

Man, Orna; Pilpel, Yitzhak

2007-03-01

A major challenge in comparative genomics is to understand how phenotypic differences between species are encoded in their genomes. Phenotypic divergence may result from differential transcription of orthologous genes, yet less is known about the involvement of differential translation regulation in species phenotypic divergence. In order to assess translation effects on divergence, we analyzed approximately 2,800 orthologous genes in nine yeast genomes. For each gene in each species, we predicted translation efficiency, using a measure of the adaptation of its codons to the organism's tRNA pool. Mining this data set, we found hundreds of genes and gene modules with correlated patterns of translational efficiency across the species. One signal encompassed entire modules that are either needed for oxidative respiration or fermentation and are efficiently translated in aerobic or anaerobic species, respectively. In addition, the efficiency of translation of the mRNA splicing machinery strongly correlates with the number of introns in the various genomes. Altogether, we found extensive selection on synonymous codon usage that modulates translation according to gene function and organism phenotype. We conclude that, like factors such as transcription regulation, translation efficiency affects and is affected by the process of species divergence.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seeley, E.J.

An apple orchard can be a very efficient mechanism for harvesting and storing energy in a usable form. The challenge is to define how the genetic, microclimatic, soil, water and cultural practice interactions limit the productive potential of apple plantings and at the same time to look ahead toward increasing the efficiency of the plant to assume continued increases in productivity for the future. Five papers were presented as summaries of some of the current and past research efforts into the factors affecting apple tree photosynthesis. (DP).

The effect of fragmentation on loader productivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

McGill, M.D.; Freadrich, J.

1994-12-31

There are many factors which affect the productivity of a front end loader. One of the most obvious is the characteristics of the material being mined. Characteristics such as size distribution, swell factor or heave, and material hardness/abrasiveness will all effect the efficiency of the mucking cycle. The focus of this paper is to look specifically at the size distribution of blasted material, and quantify the effects on loader productivity.

Factors affecting the technical efficiency of general hospitals in Iran: data envelopment analysis.

PubMed

Kalhor, Rohollah; Amini, Saeed; Sokhanvar, Mobin; Lotfi, Farhad; Sharifi, Marziye; Kakemam, Edris

2016-03-01

Restrictions on resource accessibility and its optimal application is the main challenge in organizations nowadays. The aim of this research was to study the technical efficiency and its related factors in Tehran general hospitals. This descriptive analytical study was conducted retrospectively in 2014. Fifty-four hospitals with private, university, and social security ownerships from the total 110 general hospitals were randomly selected for inclusion into this study on the basis of the share of ownership. Data were collected using a checklist with three sections, including background variables, inputs, and outputs. Seventeen (31.48%) hospitals had an efficiency score of 1 (highest efficiency score). The highest average efficiency score was in social security hospitals (84.32). Private and university hospitals ranked next with an average of 84.29 and 79.64, respectively. Analytical results showed that there was a significant relationship between hospital ownership, hospital type in terms of duty and specialization, educational field of the chief executive officer, and technical efficiency. There was no significant relationship between education level of hospital manager and technical efficiency. Most of the studied hospitals were operating at low efficiency. Therefore, policymakers should plan to improve the hospital operations and promote hospitals to an optimal level of efficiency.

Trap efficiency of reservoirs

USGS Publications Warehouse

Brune, Gunnar M.

1953-01-01

Forty-four records of reservoir trap efficiency and the factors affecting trap efficiency are analyzed. The capacity-inflow (C/I) ratio is found to offer a much closer correlation with trap efficiency than the capacity-watershed (C/W) ratio heretofore widely used. It appears likely from the cases studied that accurate timing of venting or sluicing operations to intercept gravity underflows can treble or quadruple the amount of sediment discharged from a reservoir. Desilting basins, because of their shape and method of operation, may have trap efficiencies above 90 pct even with very low C/I ratios.Semi-dry reservoirs with high C/I ratios, like John Martin Reservoir, may have trap efficiencies as low as 60 pct. Truly “dry” reservoirs, such as those in the Miami Conservancy District, probably have trap efficiencies in the 10 to 40 pct range, depending upon C/I ratio

Efficient load rating and quantification of life-cycle damage of Indiana bridges due to overweight loads.

DOT National Transportation Integrated Search

2016-02-01

In this study, a computational approach for conducting durability analysis of bridges using detailed finite element models is developed. The underlying approach adopted is based on the hypothesis that the two main factors affecting the life of a brid...

Artificial acceleration of mammalian cell reprogramming by bacterial proteins.

PubMed

Ikeda, Takashi; Uchiyama, Ikuo; Iwasaki, Mio; Sasaki, Tetsuhiko; Nakagawa, Masato; Okita, Keisuke; Masui, Shinji

2017-10-01

The molecular mechanisms of cell reprogramming and differentiation involve various signaling factors. Small molecule compounds have been identified to artificially influence these factors through interacting cellular proteins. Although such small molecule compounds are useful to enhance reprogramming and differentiation and to show the mechanisms that underlie these events, the screening usually requires a large number of compounds to identify only a very small number of hits (e.g., one hit among several tens of thousands of compounds). Here, we show a proof of concept that xenospecific gene products can affect the efficiency of cell reprogramming to pluripotency. Thirty genes specific for the bacterium Wolbachia pipientis were forcibly expressed individually along with reprogramming factors (Oct4, Sox2, Klf4 and c-Myc) that can generate induced pluripotent stem cells in mammalian cells, and eight were found to affect the reprogramming efficiency either positively or negatively (hit rate 26.7%). Mechanistic analysis suggested one of these proteins interacted with cytoskeleton to promote reprogramming. Our results raise the possibility that xenospecific gene products provide an alternative way to study the regulatory mechanism of cell identity. © 2017 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

Analytical method development of nifedipine and its degradants binary mixture using high performance liquid chromatography through a quality by design approach

NASA Astrophysics Data System (ADS)

Choiri, S.; Ainurofiq, A.; Ratri, R.; Zulmi, M. U.

2018-03-01

Nifedipin (NIF) is a photo-labile drug that easily degrades when it exposures a sunlight. This research aimed to develop of an analytical method using a high-performance liquid chromatography and implemented a quality by design approach to obtain effective, efficient, and validated analytical methods of NIF and its degradants. A 22 full factorial design approach with a curvature as a center point was applied to optimize of the analytical condition of NIF and its degradants. Mobile phase composition (MPC) and flow rate (FR) as factors determined on the system suitability parameters. The selected condition was validated by cross-validation using a leave one out technique. Alteration of MPC affected on time retention significantly. Furthermore, an increase of FR reduced the tailing factor. In addition, the interaction of both factors affected on an increase of the theoretical plates and resolution of NIF and its degradants. The selected analytical condition of NIF and its degradants has been validated at range 1 – 16 µg/mL that had good linearity, precision, accuration and efficient due to an analysis time within 10 min.

Design High-Efficiency III-V Nanowire/Si Two-Junction Solar Cell.

PubMed

Wang, Y; Zhang, Y; Zhang, D; He, S; Li, X

2015-12-01

In this paper, we report the electrical simulation results of a proposed GaInP nanowire (NW)/Si two-junction solar cell. The NW physical dimensions are determined for optimized solar energy absorption and current matching between each subcell. Two key factors (minority carrier lifetime, surface recombination velocity) affecting power conversion efficiency (PCE) of the solar cell are highlighted, and a practical guideline to design high-efficiency two-junction solar cell is thus provided. Considering the practical surface and bulk defects in GaInP semiconductor, a promising PCE of 27.5 % can be obtained. The results depict the usefulness of integrating NWs to construct high-efficiency multi-junction III-V solar cells.

Treatment time and occlusal outcome of orthognathic therapy in the East of England region.

PubMed

Jeremiah, Huw G; Cousley, Richard R; Newton, Tim; Abela, Stefan

2012-09-01

To evaluate the process of combined orthognathic and orthodontic care. To identify factors that affect treatment time and percentage Peer Assessment Rating (PAR) reduction, and the PAR efficiency factor for such cases. Retrospective multi centre study of patients who underwent orthognathic treatment in the East of England region. Analysis of consecutive cases that underwent orthognathic surgery in 2008. Inclusion criteria included pre- and post-surgery orthodontic treatment. Ten orthodontic units submitted data for a total of 118 patients. Within the sample, 64% were class III, 35% class II/1 and 1% class II/2. Overall extraction rate, excluding third molars, was 58%. Median age at bond up was 17 years. Mean total number of orthodontic attendances was 23. Median length of pre-surgical orthodontics was 23 months and post-surgical orthodontics was 7 months. Median length of total treatment was 29 months. Mean wait for surgery was 3·6 months. Diagnosis of incisor relationship and skeletal base, transfer of operator, total number of visits, tooth extraction and treatment unit affected treatment duration. Median pre- and post-treatment PAR scores were 43 and 4, respectively. Median change in PAR score was 38·5. Median per cent reduction in PAR was 90·6%. The median PAR efficiency factor (reduction in PAR score divided by treatment time in months) was 1·24. Diagnosis of incisor relationship and skeletal base correlated with percentage reduction in PAR score. Combined orthognathic treatment was effective. Factors affecting treatment duration and percentage reduction in PAR have been established.

Effects of dietary fracture toughness and dental wear on chewing efficiency in geladas (Theropithecus gelada).

PubMed

Venkataraman, Vivek V; Glowacka, Halszka; Fritz, Julia; Clauss, Marcus; Seyoum, Chalachew; Nguyen, Nga; Fashing, Peter J

2014-09-01

Chewing efficiency has been associated with fitness in mammals, yet little is known about the behavioral, ecological, and morphological factors that influence chewing efficiency in wild animals. Although research has established that dental wear and food material properties independently affect chewing efficiency, few studies have addressed the interaction among these factors. We examined chewing efficiency, measured as mean fecal particle size, as a function of seasonal shifts in diet (and corresponding changes in food fracture toughness) in a single breeding population of a grazing primate, the gelada monkey, at Guassa, Ethiopia. We also measured dental topographic traits (slope, angularity, and relief index) and relative two- and three-dimensional shearing crest lengths in a cross-sectional wear series of gelada molars. Chewing efficiency decreased during the dry season, a pattern corresponding to the consumption of foods with higher fracture toughness. Older individuals experienced the most pronounced decreases in chewing efficiency between seasons, implicating dental wear as a causal factor. This pattern is consistent with our finding that dental topographic metrics and three-dimensional relative shearing crest lengths were lowest at the last stage of wear. Integrating these lines of behavioral, ecological, and morphological evidence provides some of the first empirical support for the hypothesis that food fracture toughness and dental wear together contribute to chewing efficiency. Geladas have the highest chewing efficiencies measured thus far in primates, and may be analogous to equids in their emphasis on dental design as a means of particle size reduction in the absence of highly specialized digestive physiology. Copyright © 2014 Wiley Periodicals, Inc.

The efficiency and budgeting of public hospitals: case study of iran.

PubMed

Yusefzadeh, Hasan; Ghaderi, Hossein; Bagherzade, Rafat; Barouni, Mohsen

2013-05-01

Hospitals are the most costly and important components of any health care system, so it is important to know their economic values, pay attention to their efficiency and consider factors affecting them. The aim of this study was to assess the technical scale and economic efficiency of hospitals in the West Azerbaijan province of Iran, for which Data Envelopment Analysis (DEA) was used to propose a model for operational budgeting. This study was a descriptive-analysis that was conducted in 2009 and had three inputs and two outputs. Deap2, 1 software was used for data analysis. Slack and radial movements and surplus of inputs were calculated for selected hospitals. Finally, a model was proposed for performance-based budgeting of hospitals and health sectors using the DEA technique. The average scores of technical efficiency, pure technical efficiency (managerial efficiency) and scale efficiency of hospitals were 0.584, 0.782 and 0.771, respectively. In other words the capacity of efficiency promotion in hospitals without any increase in costs and with the same amount of inputs was about 41.5%. Only four hospitals among all hospitals had the maximum level of technical efficiency. Moreover, surplus production factors were evident in these hospitals. Reduction of surplus production factors through comprehensive planning based on the results of the Data Envelopment Analysis can play a major role in cost reduction of hospitals and health sectors. In hospitals with a technical efficiency score of less than one, the original and projected values of inputs were different; resulting in a surplus. Hence, these hospitals should reduce their values of inputs to achieve maximum efficiency and optimal performance. The results of this method was applied to hospitals a benchmark for making decisions about resource allocation; linking budgets to performance results; and controlling and improving hospitals performance.

Toward large-scale solar energy systems with peak concentrations of 20,000 suns

NASA Astrophysics Data System (ADS)

Kribus, Abraham

1997-10-01

The heliostat field plays a crucial role in defining the achievable limits for central receiver system efficiency and cost. Increasing system efficiency, thus reducing the reflective area and system cost, can be achieved by increasing the concentration and the receiver temperature. The concentration achievable in central receiver plants, however, is constrained by current heliostat technology and design practices. The factors affecting field performance are surface and tracking errors, astigmatism, shadowing, blocking and dilution. These are geometric factors that can be systematically treated and reduced. We present improvements in collection optics and technology that may boost concentration (up to 20,000 peak), achievable temperature (2,000 K), and efficiency in solar central receiver plants. The increased performance may significantly reduce the cost of solar energy in existing applications, and enable solar access to new ultra-high-temperature applications, such as: future gas turbines approaching 60% combined cycle efficiency; high-temperature thermo-chemical processes; and gas-dynamic processes.

Resource Efficient Metal and Material Recycling

NASA Astrophysics Data System (ADS)

Reuter, Markus A.; van Schaik, Antoinette

Metals enable sustainability through their use and their recyclability. However, various factors can affect the Resource Efficiency of Metal Processing and Recycling. Some typical factors that enable Resource Efficiency include and arranged under the drivers of sustainability: Environment (Maximize Resource Efficiency — Energy, Recyclates, Materials, Water, Sludges, Emissions, Land); Economic Feasibility (BAT & Recycling Systems Simulation / Digitalization, Product vis-à-vis Material Centric Recycling); and Social — Licence to Operate (Legislation, consumer, policy, theft, manual labour.). In order to realize this primary production has to be linked systemically with typical actors in the recycling chain such as Original Equipment Manufacturers (OEMs), Recyclers & Collection, Physical separation specialists as well as process metallurgical operations that produce high value metals, compounds and products that recycle back to products. This is best done with deep knowledge of multi-physics, technology, product & system design, process control, market, life cycle management, policy, to name a few. The combination of these will be discussed as Design for Sustainability (DfS) and Design for Recycling (DfR) applications.

Some factors affecting efficiency of the ultrasound-aided enzymatic hydrolysis of cotton cellulose.

PubMed

Szabo, Orsolya Erzsebet; Csiszar, Emilia

2017-01-20

The efficiency of the enzymatic hydrolysis of cellulose with low frequency ultrasound (horn-type reactor) was investigated and characterized by the concentration of reducing sugars liberated. Small squares of bleached cotton fabric were used for comparing the efficiency of different agitation methods (i.e. magnetic stirring, horizontal and vertical mechanical agitation) and ultrasound. At the same enzyme dosage and substrate level, sonication at 40, 60 and 80% amplitudes (I diss : 16.2, 32.2 and 43.4W/cm 2 , respectively) intensified the hydrolysis over the most efficient mechanical agitation (i.e. magnetic stirring) alone by 15%, 24% and 54%, respectively. For mapping the ultrasonicated field, fabric layers positioned perpendicularly to the ultrasonic probe at different distances were hydrolysed. The optimal operating conditions were reached at 60% amplitude and 9mm The yield depended mainly on important factors such as amplitude, the presence of a reflector, distance from horn and form of substrate. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effect of economic factors and energy efficiency programs on residential electricity consumption

NASA Astrophysics Data System (ADS)

Sakai, Mihoko

Many countries have implemented policies to correct market and behavioral failures that lead to inefficient energy use. It is important to know what factors and policies can effectively overcome such failures and improve energy efficiency; however, a comprehensive analysis has been difficult because of data limitations. Using state scores compiled by American organizations recently, and adopting fixed-effects regression models, I analyze the joint impacts of relevant factors and policy programs on residential electricity consumption in each U.S. state. The empirical results reveal that increases in electricity price have small and negative effects, and increases in personal income have positive effects on residential electricity sales per capita (a measure of energy efficiency). The results suggest that it may take time for economic factors to affect electricity sales. The effects of personal income suggest the difficulty of controlling residential electricity consumption; however, they also imply that there is some room in households to reduce electricity use. The study also finds that programs and budgets of several policies seem to be associated with electricity sales. The estimates from a model including interaction terms suggest the importance of including multiple policies when analyzing and designing policies to address electricity efficiency. The results also imply the possibility of rebound effects of some policies, whereby improvements in energy efficiency lead to increases in energy consumption due to the associated lower per unit cost. Future studies should analyze both short-term and long-term effects of economic factors and policies, based on improved and accumulated time series and panel data, in order to design more effective policies for improving residential electricity efficiency.

Influence of Knee Joint Extension on Submaximal Oxygen Consumption and Anaerobic Power in Cyclists

DTIC Science & Technology

1991-06-05

Cycling (pp. 91-122). Champaign, IL: Human Kinetics Books. Cavanagh, P.R. & Kram, R. (1985). Mechanical and muscular factors affecting the efficiency...M.L. (1986). Flexibility standards of the U.S. cycling team. In E.R. Burke (Ed.). Science of Cycling (pp. 47-68). Champaign, IL: Human Kinetics Books...height and pedaling cadence on power output and efficiency. In E.R. Burke (Ed.). Science of Cycling (pp. 69-907). Champaign, IL: Human Kinetics Books

Component research for future propulsion systems

NASA Technical Reports Server (NTRS)

Walker, C. L.; Weden, G. J.; Zuk, J.

1981-01-01

Factors affecting the helicopter market are reviewed. The trade-offs involving acquisition cost, mission reliability, and life cycle cost are reviewed, including civil and military aspects. The potential for advanced vehicle configurations with substantial improvements in energy efficiency, operating economics, and characteristics to satisfy the demands of the future market are identified. Advanced propulsion systems required to support these vehicle configurations are discussed, as well as the component technology for the engine systems. Considerations for selection of components in areas of economics and efficiency are presented.

Internal and external environmental factors affecting the performance of hospital-based home nursing care.

PubMed

Noh, J-W; Kwon, Y-D; Yoon, S-J; Hwang, J-I

2011-06-01

Numerous studies on HNC services have been carried out by signifying their needs, efficiency and effectiveness. However, no study has ever been performed to determine the critical factors associated with HNC's positive results despite the deluge of positive studies on the service. This study included all of the 89 training hospitals that were practising HNC service in Korea as of November 2006. The input factors affecting the performance were classified as either internal or external environmental factors. This analysis was conducted to understand the impact that the corresponding factors had on performance. Data were analysed by using multiple linear regressions. The internal and external environment variables affected the performance of HNC based on univariate analysis. The meaningful variables were internal environmental factors. Specifically, managerial resource (the number of operating beds and the outpatient/inpatient ratio) were meaningful when the multiple linear regression analysis was performed. Indeed, the importance of organizational culture (the passion of HNC nurses) was significant. This study, considering the limited market size of Korea, illustrates that the critical factor for the development of hospital-led HNC lies with internal environmental factors rather than external ones. Among the internal environmental factors, the hospitals' managerial resource-related factors (specifically, the passion of nurses) were the most important contributing element. © 2011 The Authors. International Nursing Review © 2011 International Council of Nurses.

Standardization and optimization of fluorescence in situ hybridization (FISH) for HER-2 assessment in breast cancer: A single center experience.

PubMed

Bogdanovska-Todorovska, Magdalena; Petrushevska, Gordana; Janevska, Vesna; Spasevska, Liljana; Kostadinova-Kunovska, Slavica

2018-05-20

Accurate assessment of human epidermal growth factor receptor 2 (HER-2) is crucial in selecting patients for targeted therapy. Commonly used methods for HER-2 testing are immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Here we presented the implementation, optimization and standardization of two FISH protocols using breast cancer samples and assessed the impact of pre-analytical and analytical factors on HER-2 testing. Formalin fixed paraffin embedded (FFPE) tissue samples from 70 breast cancer patients were tested for HER-2 using PathVysion™ HER-2 DNA Probe Kit and two different paraffin pretreatment kits, Vysis/Abbott Paraffin Pretreatment Reagent Kit (40 samples) and DAKO Histology FISH Accessory Kit (30 samples). The concordance between FISH and IHC results was determined. Pre-analytical and analytical factors (i.e., fixation, baking, digestion, and post-hybridization washing) affected the efficiency and quality of hybridization. The overall hybridization success in our study was 98.6% (69/70); the failure rate was 1.4%. The DAKO pretreatment kit was more time-efficient and resulted in more uniform signals that were easier to interpret, compared to the Vysis/Abbott kit. The overall concordance between IHC and FISH was 84.06%, kappa coefficient 0.5976 (p < 0.0001). The greatest discordance (82%) between IHC and FISH was observed in IHC 2+ group. A standardized FISH protocol for HER-2 assessment, with high hybridization efficiency, is necessary due to variability in tissue processing and individual tissue characteristics. Differences in the pre-analytical and analytical steps can affect the hybridization quality and efficiency. The use of DAKO pretreatment kit is time-saving and cost-effective.

Factors affecting citrus tree absorption of double-stranded ribonucleic acid, and RNAi delivery to psyllids

USDA-ARS?s Scientific Manuscript database

Modern molecular biological techniques allow for the design of molecules of ribonucleic acid capable of disrupting key biological processes of pests and diseases. A major requirement for the practical application of ribonucleic acid interference (RNAi) against insect pests is an efficient entry path...

20 CFR 416.1436 - Time and place for a hearing before an administrative law judge.

Code of Federal Regulations, 2010 CFR

2010-04-01

... SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Determinations, Administrative Review Process... the scheduled hearing because of a serious physical or mental condition, incapacitating injury, or... efficient administration of the hearing process. Factors affecting the impact of the change include, but are...

Realistic Fasting Does Not Affect Stable Isotope Levels of a Metabolically Efficient Salamander

EPA Science Inventory

Stable isotopes are commonly used to examine various aspects of animal ecology. The use of stable isotopes generally proceeds under the implicit assumption that resource use is the only factor driving variation in stable isotope levels; however, a wealth of studies demonstrate a...

Technology Transfer Issues and a New Technology Transfer Model

ERIC Educational Resources Information Center

Choi, Hee Jun

2009-01-01

The following are major issues that should be considered for efficient and effective technology transfer: conceptions of technology, technological activity and transfer, communication channels, factors affecting transfer, and models of transfer. In particular, a well-developed model of technology transfer could be used as a framework for…

[Simulation of three-dimensional green biomass of urban forests in Shenyang City and the factors affecting the biomass].

PubMed

Liu, Chang-Fu; He, Xing-Yuan; Chen, Wei; Zhao, Gui-Ling; Xue, Wen-Duo

2008-06-01

Based on the fractal theory of forest growth, stepwise regression was employed to pursue a convenient and efficient method of measuring the three-dimensional green biomass (TGB) of urban forests in small area. A total of thirteen simulation equations of TGB of urban forests in Shenyang City were derived, with the factors affecting the TGB analyzed. The results showed that the coefficients of determination (R2) of the 13 simulation equations ranged from 0.612 to 0.842. No evident pattern was shown in residual analysis, and the precisions were all higher than 87% (alpha = 0.05) and 83% (alpha = 0.01). The most convenient simulation equation was ln Y = 7.468 + 0.926 lnx1, where Y was the simulated TGB and x1 was basal area at breast height per hectare (SDB). The correlations between the standard regression coefficients of the simulation equations and 16 tree characteristics suggested that SDB was the main factor affecting the TGB of urban forests in Shenyang.

Use of Artificial Neural Networks to Examine Parameters Affecting the Immobilization of Streptokinase in Chitosan

PubMed Central

Modaresi, Seyed Mohamad Sadegh; Faramarzi, Mohammad Ali; Soltani, Arash; Baharifar, Hadi; Amani, Amir

2014-01-01

Streptokinase is a potent fibrinolytic agent which is widely used in treatment of deep vein thrombosis (DVT), pulmonary embolism (PE) and acute myocardial infarction (MI). Major limitation of this enzyme is its short biological half-life in the blood stream. Our previous report showed that complexing streptokinase with chitosan could be a solution to overcome this limitation. The aim of this research was to establish an artificial neural networks (ANNs) model for identifying main factors influencing the loading efficiency of streptokinase, as an essential parameter determining efficacy of the enzyme. Three variables, namely, chitosan concentration, buffer pH and enzyme concentration were considered as input values and the loading efficiency was used as output. Subsequently, the experimental data were modeled and the model was validated against a set of unseen data. The developed model indicated chitosan concentration as probably the most important factor, having reverse effect on the loading efficiency. PMID:25587327

Efficiency droop suppression of distance-engineered surface plasmon-coupled photoluminescence in GaN-based quantum well LEDs

NASA Astrophysics Data System (ADS)

Li, Yufeng; Wang, Shuai; Su, Xilin; Tang, Weihan; Li, Qiang; Guo, Maofeng; Zhang, Ye; Zhang, Minyan; Yun, Feng; Hou, Xun

2017-11-01

Ag coated microgroove with extreme large aspect-ratio of 500:1 was fabricated on p-GaN capping layer to investigate the coupling behavior between quantum wells and surface plasmon in highly spatial resolution. Significant photoluminescence enhancement was observed when the distance between Ag film and QWs was reduced from 220 nm to about 20 nm. A maximum enhancement ratio of 18-fold was achieved at the groove bottom where the surface plasmonic coupling was considered the strongest. Such enhancement ratio was found highly affected by the excitation power density. It also shows high correlation to the internal quantum efficiency as a function of coupling effect and a maximum Purcell Factor of 1.75 was estimated at maximum coupling effect, which matches number calculated independently from the time-resolved photoluminescence measurement. With such Purcell Factor, the efficiency was greatly enhanced and the droop was significantly suppressed.

Efficiency loss of thin film Cu(InxGa1-x)Se(S) solar panels by lamination process

NASA Astrophysics Data System (ADS)

Xu, Li

2017-04-01

Efficiency loss of thin film Cu(InxGa1-x)Se(S) (CIGS) solar panels by lamination process has been compromising the final output power in commercial products of solar modules, but few reports have been published on such issue, as the majority of the investigation is focused on the efficiency at the circuit level, i.e., before lamination process. In this paper, we studied the effect of lamination process to the efficiency loss of thin film CIGS solar panels. It was observed that the fill factor degradation dominated the efficiency loss with the small change of Voc and Jsc. Experiments showed that neither the temperature nor the pressure, nor the two combined in the lamination process is the root cause of the efficiency loss; instead, the ethylene vinyl acetate (EVA) layer as the encapsulation material which directly contacts the solar cell devices was the major factor responsible for the efficiency loss. It was found that the gel content of the cured EVA film after lamination was highly correlated to the efficiency loss. The higher the gel content, the higher the efficiency loss. The mismatch of coefficient of thermal expansion between the EVA film and the CIGS thin film resulted in compressive stress in the device layer after lamination process. The compressive stress is speculated to affect the lattice defects, but need to be confirmed with the measurement of capacitance voltage (CV) and drive level capacitance profiling (DLCP). Three-day sun soak was then carried out and it was observed that the fill factor recovered significantly and so did the efficiency. Experiments also showed that there was no impact of chemical erosion on the front electrode of transparent conductive oxide (TCO) films by chemicals released from the EVA films during lamination.

An approach to optimize the batch mixing process for improving the quality consistency of the products made from traditional Chinese medicines*

PubMed Central

Yan, Bin-jun; Qu, Hai-bin

2013-01-01

The efficacy of traditional Chinese medicine (TCM) is based on the combined effects of its constituents. Variation in chemical composition between batches of TCM has always been the deterring factor in achieving consistency in efficacy. The batch mixing process can significantly reduce the batch-to-batch quality variation in TCM extracts by mixing them in a well-designed proportion. However, reducing the quality variation without sacrificing too much of the production efficiency is one of the challenges. Accordingly, an innovative and practical batch mixing method aimed at providing acceptable efficiency for industrial production of TCM products is proposed in this work, which uses a minimum number of batches of extracts to meet the content limits. The important factors affecting the utilization ratio of the extracts (URE) were studied by simulations. The results have shown that URE was affected by the correlation between the contents of constituents, and URE decreased with the increase in the number of targets and the relative standard deviations of the contents. URE could be increased by increasing the number of storage tanks. The results have provided a reference for designing the batch mixing process. The proposed method has possible application value in reducing the quality variation in TCM and providing acceptable production efficiency simultaneously. PMID:24190450

An approach to optimize the batch mixing process for improving the quality consistency of the products made from traditional Chinese medicines.

PubMed

Yan, Bin-jun; Qu, Hai-bin

2013-11-01

The efficacy of traditional Chinese medicine (TCM) is based on the combined effects of its constituents. Variation in chemical composition between batches of TCM has always been the deterring factor in achieving consistency in efficacy. The batch mixing process can significantly reduce the batch-to-batch quality variation in TCM extracts by mixing them in a well-designed proportion. However, reducing the quality variation without sacrificing too much of the production efficiency is one of the challenges. Accordingly, an innovative and practical batch mixing method aimed at providing acceptable efficiency for industrial production of TCM products is proposed in this work, which uses a minimum number of batches of extracts to meet the content limits. The important factors affecting the utilization ratio of the extracts (URE) were studied by simulations. The results have shown that URE was affected by the correlation between the contents of constituents, and URE decreased with the increase in the number of targets and the relative standard deviations of the contents. URE could be increased by increasing the number of storage tanks. The results have provided a reference for designing the batch mixing process. The proposed method has possible application value in reducing the quality variation in TCM and providing acceptable production efficiency simultaneously.

[Sustainability of ecological water transfer and rehabilitation project based on participatory survey].

PubMed

Wang, Yu; Feng, Qi; Chen, Li-Juan; Yu, Teng-Fei

2014-01-01

In the arid inland area of Northwest China, the ecological water transfer and rehabilitation project (EWTRP) is an important measure to restore the deteriorated ecosystem. However, the sustainability of the project is affected by many socio-economic factors. This research was based on results of the questionnaire from Ejina County's farmer households, which included the farmer households' attitude, livelihood and the efficiency of the water resource usage. The results showed that although the EWTRP had made great achievements in vegetation restoration, but the sustainability of the project was affected by the following factors: the ecologically-motivated relocated/resettled herdsmen mainly relied on the compensation from the project, causing them a hard living, and increasing the risk of maintaining the current achievement; the project didn't have a positive impact on water-saving agriculture, the efficiency of water usage was relatively low and had not yet reached the final goal; the compensation of the project only considered the loss of agriculture, but neglected the externality and publicity of eco-water. We suggest that developing education, offering job opportunity and training programs, improving the efficiency of water usage and establishing reasonable water resources compensation mechanisms are needed to be considered as main domain of environmental recovery as well as ecological water transfer and rehabilitation.

Estimation of hospital efficiency--do different definitions and casemix measures for hospital output affect the results?

PubMed

Vitikainen, Kirsi; Street, Andrew; Linna, Miika

2009-02-01

Hospital efficiency has been the subject of numerous health economics studies, but there is little evidence on how the chosen output and casemix measures affect the efficiency results. The aim of this study is to examine the robustness of efficiency results due to these factors. Comparison is made between activities and episode output measures, and two different output grouping systems (Classic and FullDRG). Non-parametric data envelopment analysis is used as an analysis technique. The data consist of all public acute care hospitals in Finland in 2005 (n=40). Efficiency estimates were not found to be highly sensitive to the choice between episode and activity descriptions of output, but more so to the choice of DRG grouping system. Estimates are most sensitive to scale assumptions, with evidence of decreasing returns to scale in larger hospitals. Episode measures are generally to be preferred to activity measures because these better capture the patient pathway, while FullDRGs are preferred to Classic DRGs particularly because of the better description of outpatient output in the former grouping system. Attention should be paid to reducing the extent of scale inefficiency in Finland.

Experimental investigation on the hydrodynamic performance of a wave energy converter

NASA Astrophysics Data System (ADS)

Zheng, Xiong-bo; Ma, Yong; Zhang, Liang; Jiang, Jin; Liu, Heng-xu

2017-06-01

Wave energy is an important type of marine renewable energy. A wave energy converter (WEC) moored with two floating bodies was developed in the present study. To analyze the dynamic performance of the WEC, an experimental device was designed and tested in a tank. The experiment focused on the factors which impact the motion and energy conversion performance of the WEC. Dynamic performance was evaluated by the relative displacements and velocities of the oscillator and carrier which served as the floating bodies of WEC. Four factors were tested, i.e. wave height, wave period, power take-off (PTO) damping, and mass ratio ( R M) of the oscillator and carrier. Experimental results show that these factors greatly affect the energy conversion performance, especially when the wave period matches R M and PTO damping. According to the results, we conclude that: (a) the maximization of the relative displacements and velocities leads to the maximization of the energy conversion efficiency; (b) the larger the wave height, the higher the energy conversion efficiency will be; (c) the relationships of energy conversion efficiency with wave period, PTO damping, and R M are nonlinear, but the maximum efficiency is obtained when these three factors are optimally matched. Experimental results demonstrated that the energy conversion efficiency reached the peak at 28.62% when the wave height was 120 mm, wave period was 1.0 s, R M was 0.21, and the PTO damping was corresponding to the resistance of 100 Ω.

Economic efficiency of application of innovative materials and structures in high-rise construction

NASA Astrophysics Data System (ADS)

Golov, Roman; Dikareva, Varvara; Gorshkov, Roman; Agarkov, Anatoly

2018-03-01

The article is devoted to the analysis of technical and economic efficiency of application of tube confined concrete structures in high-rise construction. The study of comparative costs of materials with the use of different supporting columns was carried out. The main design, operational, technological and economic advantages of the tube confined concrete technology were evaluated, conclusions were drawn about the high strength and deformation properties of axial compression of steel tubes filled with high-strength concrete. The efficiency of the tube confined concrete use is substantiated, which depends mainly on the scale factor and percentage of reinforcement affecting its load-bearing capacity.

Managing Nitrogen in the anthropocene: integrating social and ecological science

NASA Astrophysics Data System (ADS)

Zhang, X.; Mauzerall, D. L.; Davidson, E. A.; Kanter, D.; Cai, R.; Searchinger, T.

2014-12-01

Human alteration of the global nitrogen cycle by agricultural activities has provided nutritious food to society, but also poses increasing threats to human and ecosystem health through unintended pollution. Managing nitrogen more efficiently in crop production is critical for addressing both food security and environmental challenges. Technologies and management practices have been developed to increase the uptake of applied nitrogen by crops. However, nitrogen use efficiency (NUE, yield per unit nitrogen input) is also affected by social and economic factors. For example, to maximize profit, farmers may change crop choice or their nitrogen application rate, both of which lead to a change in NUE. To evaluate such impacts, we use both theoretical and empirical approaches on micro (farm) and macro (national) scales: 1) We developed a bio-economic model (NUE3) on a farm scale to investigate how market signals (e.g. fertilizer and crop prices), government policies, and nitrogen-efficient technologies affect NUE. We demonstrate that if factors that influence nitrogen inputs (e.g. fertilizer-to-crop price ratios) are not considered, NUE projections will be poorly constrained. The impact of nitrogen-efficient technologies on NUE not only depends on how technology changes the production function, but also relies on the prices of the technologies, fertilizers, and crops. 2) We constructed a database of the nitrogen budget in crop production for major crops and major crop producing countries from 1961 to 2010. Using this database, we investigate historical trends of NUE and its relationship to agronomic, economic, social, and policy factors. We find that NUE in most developed countries follows a "U-shape" relationship with income level, consistent with the Environmental Kuznets Curve theory. According to the dynamics revealed in the NUE3 model, we propose three major pathways by which economic development affects NUE, namely consumption, technology, and public policy. Overall, our research suggests that it is critical to include social and economic processes when studying perturbations of the global nitrogen cycle and crafting environmental and food security policy. Better collaboration across disciplines is essential to improve nitrogen management in the anthropocene.

Comparison of daily and weekly precipitation sampling efficiencies using automatic collectors

USGS Publications Warehouse

Schroder, L.J.; Linthurst, R.A.; Ellson, J.E.; Vozzo, S.F.

1985-01-01

Precipitation samples were collected for approximately 90 daily and 50 weekly sampling periods at Finley Farm, near Raleigh, North Carolina from August 1981 through October 1982. Ten wet-deposition samplers (AEROCHEM METRICS MODEL 301) were used; 4 samplers were operated for daily sampling, and 6 samplers were operated for weekly-sampling periods. This design was used to determine if: (1) collection efficiences of precipitation are affected by small distances between the Universal (Belfort) precipitation gage and collector; (2) measurable evaporation loss occurs and (3) pH and specific conductance of precipitation vary significantly within small distances. Average collection efficiencies were 97% for weekly sampling periods compared with the rain gage. Collection efficiencies were examined by seasons and precipitation volume. Neither factor significantly affected collection efficiency. No evaporation loss was found by comparing daily sampling to weekly sampling at the collection site, which was classified as a subtropical climate. Correlation coefficients for pH and specific conductance of daily samples and weekly samples ranged from 0.83 to 0.99.Precipitation samples were collected for approximately 90 daily and 50 weekly sampling periods at Finley farm, near Raleigh, North Carolina from August 1981 through October 1982. Ten wet-deposition samplers were used; 4 samplers were operated for daily sampling, and 6 samplers were operated for weekly-sampling periods. This design was used to determine if: (1) collection efficiencies of precipitation are affected by small distances between the University (Belfort) precipitation gage and collector; (2) measurable evaporation loss occurs and (3) pH and specific conductance of precipitation vary significantly within small distances.

Quantum chemical study of the inhibition of the corrosion of mild steel in H2SO4 by some antibiotics.

PubMed

Eddy, Nnabuk O; Ibok, Udo J; Ebenso, Eno E; El Nemr, Ahmed; El Ashry, El Sayed H

2009-09-01

The inhibition efficiency of some antibiotics against mild steel corrosion was studied using weight loss and quantum chemical techniques. Values of inhibition efficiency obtained from weight loss measurements correlated strongly with theoretical values obtained through semi empirical calculations. High correlation coefficients were also obtained between inhibition efficiency of the antibiotics and some quantum chemical parameters, including frontier orbital (E (HOMO) and E (LUMO)), dipole moment, log P, TNC and LSER parameters (critical volume and dipolar-polarisability factor), which indicated that these parameters affect the inhibition efficiency of the compounds. It was also found that quantitative structure activity relation can be used to adequately predict the inhibition effectiveness of these compounds.

Determinants of efficiency in the provision of municipal street-cleaning and refuse collection services

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benito-Lopez, Bernardino, E-mail: benitobl@um.es; Rocio Moreno-Enguix, Maria del, E-mail: mrmoreno@um.es; Solana-Ibanez, Jose, E-mail: jsolana@um.es

Effective waste management systems can make critical contributions to public health, environmental sustainability and economic development. The challenge affects every person and institution in society, and measures cannot be undertaken without data collection and a quantitative analysis approach. In this paper, the two-stage double bootstrap procedure of is used to estimate the efficiency determinants of Spanish local entities in the provision of public street-cleaning and refuse collection services. The purpose is to identify factors that influence efficiency. The final sample comprised 1072 municipalities. In the first stage, robust efficiency estimates are obtained with Data Envelopment Analysis (DEA). We apply themore » second stage, based on a truncated-regression, to estimate the effect of a group of environmental factors on DEA estimates. The results show the existence of a significant relation between efficiency and all the variables analysed (per capita income, urban population density, the comparative index of the importance of tourism and that of the whole economic activity). We have also considered the influence of a dummy categorical variable - the political sign of the governing party - on the efficient provision of the services under study. The results from the methodology proposed show that municipalities governed by progressive parties are more efficient.« less

Determinants of efficiency in the provision of municipal street-cleaning and refuse collection services.

PubMed

Benito-López, Bernardino; Moreno-Enguix, María del Rocio; Solana-Ibañez, José

2011-06-01

Effective waste management systems can make critical contributions to public health, environmental sustainability and economic development. The challenge affects every person and institution in society, and measures cannot be undertaken without data collection and a quantitative analysis approach. In this paper, the two-stage double bootstrap procedure of Simar and Wilson (2007) is used to estimate the efficiency determinants of Spanish local entities in the provision of public street-cleaning and refuse collection services. The purpose is to identify factors that influence efficiency. The final sample comprised 1072 municipalities. In the first stage, robust efficiency estimates are obtained with Data Envelopment Analysis (DEA). We apply the second stage, based on a truncated-regression, to estimate the effect of a group of environmental factors on DEA estimates. The results show the existence of a significant relation between efficiency and all the variables analysed (per capita income, urban population density, the comparative index of the importance of tourism and that of the whole economic activity). We have also considered the influence of a dummy categorical variable - the political sign of the governing party - on the efficient provision of the services under study. The results from the methodology proposed show that municipalities governed by progressive parties are more efficient. Copyright © 2011 Elsevier Ltd. All rights reserved.

Research Program on Factors Affecting the Brightness of AC Plasma Panels.

DTIC Science & Technology

1983-06-01

representing the second excited electronic con - figuration in neon. In an effort to devise means to improve the brightness and/or efficiency of neon filled...obtained from several panels was found to be very good (Ref. 6), a factor providing important support for the validity of the kinetic modeling pro - cedures...pressure neon Penning mixtures for I conditions typical of plasma panel displays [II]. Their work has pro - vied valuable insight regarding the electrical

Factors affecting utilization of university health services in a tertiary institution in South-West Nigeria.

PubMed

Obiechina, G O; Ekenedo, G O

2013-01-01

Most university health services have extensive health infrastructures, for the provision of effective and efficient health services to the students. In this study, we have tried to determine student's perception of factors affecting their utilization. To determine students' perception of health care services provided in a tertiary institution and assess students' attitude towards utilization. Simple random sampling technique was used to select 540 respondents, comprising of 390 males and 150 females. A structured and self-administered questionnaire was the instrument used to collect data for the study, while data collected was analyzed using descriptive statistics of frequency count and percentage. High cost of drugs (72.0%), non availability of essential drugs (54.8%), time spent waiting for treatment (67.2%), inadequate referral services (81.7%), and satisfaction with services (60.6%) were considered by the respondents as factors affecting the utilization of university health services. Students-medical staff relationship and accessibility to health facility (77.6% and 74.3% respectively) were, however, not considered as factors that affect utilization of university health services. It is recommended that to improve utilization and cost of care, government should make necessary efforts to incorporate tertiary institution into National Health Insurance scheme so that students above the age of 18 years can benefit from free treatment.

Factors Affecting the Capture Efficiency of a Fume Extraction Torch for Gas Metal Arc Welding.

PubMed

Bonthoux, Francis

2016-07-01

Welding fumes are classified as Group 2B 'possibly carcinogenic' and this prompts to the implementation of local exhaust ventilation (LEV). The fume extraction torch with LEV integrated into the tool is the most attractive solution but its capture efficiency is often disappointing in practice. This study assesses the main parameters affecting fume capture efficiency namely the extraction flow rate, the positioning of the suction openings on the torch, the angle of inclination of the torch to the workpiece during welding, the metal transfer modes, and the welding deposition rate. The theoretical velocity induced by suction, estimated from the extraction flow rate and the position of the suction openings, is the main parameter affecting effectiveness of the device. This is the design parameter and its value should never be <0.25 m s(-1) The angle of the torch relative to the workpiece also has a great deal of influence. To improve efficiency, work station layouts need to favour positions where the torch is held with angles closer to perpendicular (<15°). Welding with high deposition rates (>1.1g s(-1)) and spray transfer leads to low capture efficiency if induced velocities are <0.5 m s(-1) The results of the study can be used in the design of integrated on-torch extraction systems and provide information for fixing system objectives. © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Grain sorghum is a viable feedstock for ethanol production.

PubMed

Wang, D; Bean, S; McLaren, J; Seib, P; Madl, R; Tuinstra, M; Shi, Y; Lenz, M; Wu, X; Zhao, R

2008-05-01

Sorghum is a major cereal crop in the USA. However, sorghum has been underutilized as a renewable feedstock for bioenergy. The goal of this research was to improve the bioconversion efficiency for biofuels and biobased products from processed sorghum. The main focus was to understand the relationship among "genetics-structure-function-conversion" and the key factors impacting ethanol production, as well as to develop an energy life cycle analysis model (ELCAM) to quantify and prioritize the saving potential from factors identified in this research. Genetic lines with extremely high and low ethanol fermentation efficiency and some specific attributes that may be manipulated to improve the bioconversion rate of sorghum were identified. In general, ethanol yield increased as starch content increased. However, no linear relationship between starch content and fermentation efficiency was found. Key factors affecting the ethanol fermentation efficiency of sorghum include protein digestibility, level of extractable proteins, protein and starch interaction, mash viscosity, amount of phenolic compounds, ratio of amylose to amylopectin, and formation of amylose-lipid complexes in the mash. A platform ELCAM with a base case showed a positive net energy value (NEV) = 25,500 Btu/gal EtOH. ELCAM cases were used to identify factors that most impact sorghum use. For example, a yield increase of 40 bu/ac resulted in NEV increasing from 7 million to 12 million Btu/ac. An 8% increase in starch provided an incremental 1.2 million Btu/ac.

Factors Affecting the Adoption of Telemedicine: A Three-Country Empirical Investigation

ERIC Educational Resources Information Center

Mansouri-Rad, Parand

2012-01-01

Telemedicine improves access to information and healthcare services. Not only more cost effective and more efficient method of providing health care than the traditional methods, telemedicine is the most convenient method of delivering healthcare. However, the adoption of telemedicine has been challenging. The purpose of this dissertation is to…

Knowledge of Global Climate Change: View of Iranian University Students

ERIC Educational Resources Information Center

Salehi, Sadegh; Nejad, Zahra Pazuki; Mahmoudi, Hossein; Burkart, Stefan

2016-01-01

This article assesses students' understanding of global climate change (GCC) and social factors affecting it. It was hypothesized that students who demonstrate pro-environmental attitudes are more likely to possess higher knowledge of GCC. It was further hypothesized that trust and personal efficiency would have a positive effect on the knowledge…

Using a Web-Based System to Estimate the Cost of Online Course Production

ERIC Educational Resources Information Center

Gordon, Stuart; He, Wu; Abdous, M'hammed

2009-01-01

The increasing demand for online courses requires efficient and low cost production. Since the decision to develop online courses is often affected by financial factors, it is becoming increasingly important to determine, upfront, the cost of online course production. Many of the programs and educators interested in developing online courses…

Factors affecting expression of the recF gene of Escherichia coli K-12.

PubMed

Sandler, S J; Clark, A J

1990-01-31

This report describes four factors which affect expression of the recF gene from strong upstream lambda promoters under temperature-sensitive cIAt2-encoded repressor control. The first factor was the long mRNA leader sequence consisting of the Escherichia coli dnaN gene and 95% of the dnaA gene and lambda bet, N (double amber) and 40% of the exo gene. When most of this DNA was deleted, RecF became detectable in maxicells. The second factor was the vector, pBEU28, a runaway replication plasmid. When we substituted pUC118 for pBEU28, RecF became detectable in whole cells by the Coomassie blue staining technique. The third factor was the efficiency of initiation of translation. We used site-directed mutagenesis to change the mRNA leader, ribosome-binding site and the 3 bp before and after the translational start codon. Monitoring the effect of these mutational changes by translational fusion to lacZ, we discovered that the efficiency of initiation of translation was increased 30-fold. Only an estimated two- or threefold increase in accumulated levels of RecF occurred, however. This led us to discover the fourth factor, namely sequences in the recF gene itself. These sequences reduce expression of the recF-lacZ fusion genes 100-fold. The sequences responsible for this decrease in expression occur in four regions in the N-terminal half of recF. Expression is reduced by some sequences at the transcriptional level and by others at the translational level.

Plasma-assisted CO2 conversion: optimizing performance via microwave power modulation

NASA Astrophysics Data System (ADS)

Britun, Nikolay; Silva, Tiago; Chen, Guoxing; Godfroid, Thomas; van der Mullen, Joost; Snyders, Rony

2018-04-01

Significant improvement in the energy efficiency of plasma-assisted CO2 conversion is achieved with applied power modulation in a surfaguide microwave discharge. The obtained values of CO2 conversion and energy efficiency are, respectively, 0.23 and 0.33 for a 0.95 CO2  +  0.05 N2 gas mixture. Analysis of the energy relaxation mechanisms shows that power modulation can potentially affect the vibrational-translational energy exchange in plasma. In our case, however, this mechanism does not play a major role, likely due to the low degree of plasma non-equilibrium in the considered pressure range. Instead, the gas residence time in the discharge active zone together with plasma pulse duration are found to be the main factors affecting the CO2 conversion efficiency at low plasma pulse repetition rates. This effect is confirmed experimentally by the in situ time-resolved two-photon absorption laser-induced fluorescence measurements of CO molecular density produced in the discharge as a result of CO2 decomposition.

[New distribution forms for pharmaceuticals--a logistic perspective].

PubMed

Grund, J; Vartdal, T E

1998-11-10

Pharmaceuticals are an important input in health care. As a complement to other modes of treatment and as a substitute for hospitalisation, they affect the health of individuals and populations. Enormous public financial resources are spent on pharmaceuticals, and halting the growth in expenditures is a political objective. Factors with room for improvement include drug use efficiency, cost-efficient prescription, purchasing prices and distribution. High distribution costs affect prices and, thus, the assessment of product cost vs. utility. Changes in the distribution system may be important, for three reasons: First, increased capital costs call for higher efficiency. Second, increased competition requires improved logistics. And third, information technology has opened up for new supply chain solutions. Direct sales solutions are being considered, and were discussed in a Norwegian public report on the matter, but no final conclusion has been reached. This article discusses changes in the supply of pharmaceuticals and the development of the market. Alternative supply chains are outlined, including what role the postal service may play in a deregulated pharmaceutical market.

Review on factors affecting the performance of pulse detonation engine

NASA Astrophysics Data System (ADS)

Tripathi, Saurabh; Pandey, Krishna Murari

2018-04-01

Now a day's rocket engines (air-breathing type) are being used for aerospace purposes but the studies have shown that these are less efficient, so alternatives are being searched for these. Pulse Detonation Engine (PDE) is one such efficient engine which can replace the rocket engines. In this review paper, different researches have been cited. As can be observed from various researches, insertion of obstacles is better. Deflagration to Detonation(DDT) transition process is found to be most important factor. So a lot of researches are being done considering this DDT chamber. Also, the ignition chamber and ejector were found to improve the effectiveness of PDE. The PDE works with a range of Mach 0-4. Flame acceleration is also found to increase the DDT process. Use of valve and valveless engine has also been compared. Various other factors have been focused in this review paper which is found to boost PDE performance.

Growth factors and chronic wound healing: past, present, and future.

PubMed

Goldman, Robert

2004-01-01

Growth substances (cytokines and growth factors) are soluble signaling proteins affecting the process of normal wound healing. Cytokines govern the inflammatory phase that clears cellular and extracellular matrix debris. Wound repair is controlled by growth factors (platelet-derived growth factor [PDGF], keratinocyte growth factor, and transforming growth factor beta). Endogenous growth factors communicate across the dermal-epidermal interface. PDGF is important for most phases of wound healing. Becaplermin (PDGF-BB), the only growth factor approved by the Food and Drug Administration, requires daily application for neuropathic wound healing. Gene therapy is under development for more efficient growth factor delivery; a single application will induce constitutive growth factor expression for weeks. Based on dramatic preclinical animal studies, a phase 1 clinical trial planned on a PDGF genetic construct appears promising.

Benefit Assessment for Metroplex Tactical Runway Configuration Management (mTRCM) in a Simulated Environment

NASA Technical Reports Server (NTRS)

Phojanamongkolkij, Nipa; Oseguera-Lohr, Rosa M.; Lohr, Gary W.; Robbins, Steven W.; Fenbert, James W.; Hartman, Christopher L.

2015-01-01

The System-Oriented Runway Management (SORM) concept is a collection of capabilities focused on a more efficient use of runways while considering all of the factors that affect runway use. Tactical Runway Configuration Management (TRCM), one of the SORM capabilities, provides runway configuration and runway usage recommendations, and monitoring the active runway configuration for suitability given existing factors. This report focuses on the metroplex environment, with two or more proximate airports having arrival and departure operations that are highly interdependent. The myriad of factors that affect metroplex opeations require consideration in arriving at runway configurations that collectively best serve the system as a whole. To assess the metroplex TRCM (mTRCM) benefit, the performance metrics must be compared with the actual historical operations. The historical configuration schedules can be viewed as the schedules produced by subject matter experts (SMEs), and therefore are referred to as the SMEs' schedules. These schedules were obtained from the FAA's Aviation System Performance Metrics (ASPM) database; this is the most representative information regarding runway configuration selection by SMEs. This report focused on a benefit assessment of total delay, transit time, and throughput efficiency (TE) benefits using the mTRCM algorithm at representative volumes for today's traffic at the New York metroplex (N90).

Formulation strategies for optimizing the morphology of polymeric bulk heterojunction organic solar cells: a brief review

NASA Astrophysics Data System (ADS)

Vongsaysy, Uyxing; Bassani, Dario M.; Servant, Laurent; Pavageau, Bertrand; Wantz, Guillaume; Aziz, Hany

2014-01-01

Polymeric bulk heterojunction (BHJ) organic solar cells represent one of the most promising technologies for renewable energy with a low fabrication cost. Control over BHJ morphology is one of the key factors in obtaining high-efficiency devices. This review focuses on formulation strategies for optimizing the BHJ morphology. We address how solvent choice and the introduction of processing additives affect the morphology. We also review a number of recent studies concerning prediction methods that utilize the Hansen solubility parameters to develop efficient solvent systems.

Household adoption of energy and water-efficient appliances: An analysis of attitudes, labelling and complementary green behaviours in selected OECD countries.

PubMed

Dieu-Hang, To; Grafton, R Quentin; Martínez-Espiñeira, Roberto; Garcia-Valiñas, Maria

2017-07-15

Using a household-based data set of more than 12,000 households from 11 OECD countries, we analyse the factors underlying the decision by households to adopt energy-efficient and water-efficient equipment. We evaluate the roles of both attitudes and labelling schemes on the adoption of energy and water-efficient equipment, and also the interaction and complementarity between energy and water conservation behaviours. Our findings show: one, 'green' social norms and favourable attitudes towards the environment are associated with an increased likelihood of households' adoption of energy and water-efficient appliances; two, households' purchase decisions are positively affected by their awareness, understanding, and trust of labelling schemes; and three, there is evidence of complementarity between energy conservation and water conservation behaviours. Copyright © 2017 Elsevier Ltd. All rights reserved.

Putting performance in context: the perceived influence of environmental factors on work-based performance.

PubMed

Stroud, Lynfa; Bryden, Pier; Kurabi, Bochra; Ginsburg, Shiphra

2015-10-01

Context shapes behaviours yet is seldom considered when assessing competence. Our objective was to explore attending physicians' and trainees' perceptions of the Internal Medicine Clinical Teaching Unit (CTU) environment and how they thought contextual factors affected their performance. 29 individuals recently completing CTU rotations participated in nine level-specific focus groups (2 with attending physicians, 3 with senior and 2 with junior residents, and 2 with students). Participants were asked to identify environmental factors on the CTU and to describe how these factors influenced their own performance across CanMEDS roles. Discussions were analyzed using constructivist grounded theory. Five major contextual factors were identified: Busyness, Multiple Hats, Other People, Educational Structures, and Hospital Resources and Policies. Busyness emerged as the most important, but all factors had a substantial perceived impact on performance. Participants felt their performance on the Manager and Scholar roles was most affected by environmental factors (mostly negatively, due to decreased efficiency and impact on learning). In complex workplace environments, numerous factors shape performance. These contextual factors and their impact need to be considered in observations and judgements made about performance in the workplace, as without this understanding conclusions about competency may be flawed.

Search for supersymmetry in 8 TeV proton-proton collision events with bottom-quark jets and missing transverse energy

NASA Astrophysics Data System (ADS)

Kreis, Benjamin

In the absence of meaningful federal action, many states have adopted clean energy policies aimed at reducing carbon emissions. Among these policies is the energy efficiency resource standard (EERS), adopted by 33 states mostly in the last decade, which sets an energy consumption reduction target for some or all regulated utilities within a state. My paper examines what factors affect a state's likelihood of adopting an EERS, and whether those factors are different for EERS policies compared with other clean energy policies. The energy policy literature features many studies of clean energy policy adoption, but none have focused specifically on EERS adoption. I theorized that energy efficiency potential being relatively homogeneously distributed across states (compared to renewable energy potential) and efficiency's relative inexpensiveness as a resource would result in a unique set of factors being associated with the likelihood of EERS adoption. Specifically, I expected that three internal determinants--the presence of utility rate decoupling in a state, a state's political ideology, and the state's average retail price of residential electricity--affect a state's likelihood of adopting an EERS. To test these hypotheses, I estimated several multiple regression models using an event history analysis approach and found that citizen liberalism, level of electricity consumption, and a time counter variable were all statistically significant and positive predictors of state adoption of an EERS, all else equal. I found no association between decoupling or electricity price and EERS adoption, though in the case of the former that may be a result of insufficient data.

Induction of rice mutations by high hydrostatic pressure.

PubMed

Zhang, Wei; Liu, Xuncheng; Zheng, Feng; Zeng, Songjun; Wu, Kunlin; da Silva, Jaime A Teixeira; Duan, Jun

2013-09-01

High hydrostatic pressure (HHP) is an extreme thermo-physical factor that affects the synthesis of DNA, RNA and proteins and induces mutagenesis in microorganisms. Our previous studies showed that exposure to 25-100 MPa HHP for 12 h retarded the germination and affected the viability of rice (Oryza sativa L.) seeds, increased the tolerance of rice plants to cold stress and altered gene expression patterns in germinating rice seeds. However, the mutagenic effect of HHP on rice remains unknown. In this study, exposure to 25, 50, 75 or 100 MPa for 12 h HHP could efficiently induce variation in rice plants. Furthermore, presoaking time and HHP strength during HHP treatment affected the efficiency of mutation. In addition, the Comet assay revealed that exposure to 25-100 MPa HHP for 12 h induced DNA strand breakage in germinating seeds and may have been the source of mutations. Our results suggest that HHP is a promising physical mutagen in rice breeding. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Are participants in markets for water rights more efficient in the use of water than non-participants? A case study for Limarí Valley (Chile).

PubMed

Molinos-Senante, María; Donoso, Guillermo; Sala-Garrido, Ramon

2016-06-01

The need to increase water productivity in agriculture has been stressed as one of the most important factors to achieve greater agricultural productivity and sustainability. The main aim of this paper is to investigate whether there are differences in water use efficiency (WUE) between farmers who participate in water markets and farmers who do not participate in them. Moreover, the use of a non-radial data envelopment analysis model allows to compute global efficiency (GE), WUE as well the efficiency in the use of other inputs such as fertilizers, pesticides, energy, and labor. In a second stage, external factors that may affect GE and WUE are explored. The empirical application focuses on a sample of farmers located in Limarí Valley (Chile) where regulated permanent water rights (WR) markets for surface water have a long tradition. Results illustrate that WR sellers are the most efficient in the use of water while non-traders are the farmers that present the lowest WUE. From a policy perspective, significant conclusions are drawn from the assessment of agricultural water productivity in the framework of water markets.

Factors affecting the retirement of commercial transport jet aircraft

NASA Technical Reports Server (NTRS)

Spencer, F. A.

1979-01-01

The historical background of the technology and economics of aircraft replacement and retirement in the prejet era is reviewed in order to determine whether useful insights can be obtained applicable to the jet era. Significant differences between the two periods are noted. New factors are identified and examined. Topics discussed include concern over current policies regarding deregulation, regulatory reform, and retroactive noise regulations; financing and compliance legislation; aging; economic environment and inflation; technological progress; fuel efficiency and cost; and a financial perspective of replacement decisions.

Are Physicians Likely to Adopt Emerging Mobile Technologies? Attitudes and Innovation Factors Affecting Smartphone Use in the Southeastern United States

PubMed Central

Putzer, Gavin J; Park, Yangil

2012-01-01

The smartphone has emerged as an important technological device to assist physicians with medical decision making, clinical tasks, and other computing functions. A smartphone is a device that combines mobile telecommunication with Internet accessibility as well as word processing. Moreover, smartphones have additional features such as applications pertinent to clinical medicine and practice management. The purpose of this study was to investigate the innovation factors that affect a physician's decision to adopt an emerging mobile technological device such as a smartphone. The study sample consisted of 103 physicians from community hospitals and academic medical centers in the southeastern United States. Innovation factors are elements that affect an individual's attitude toward using and adopting an emerging technology. In our model, the innovation characteristics of compatibility, job relevance, the internal environment, observability, personal experience, and the external environment were all significant predictors of attitude toward using a smartphone. These influential innovation factors presumably are salient predictors of a physician's attitude toward using a smartphone to assist with clinical tasks. Health information technology devices such as smartphones offer promise as a means to improve clinical efficiency, medical quality, and care coordination and possibly reduce healthcare costs. PMID:22737094

How can we maximize the use of our operating lists? An analysis of factors influencing theatre efficiency in oculoplastic day surgery.

PubMed

Nagendran, Sonali T; Siah, We Fong; Litwin, Andre; Barbosa, Christine; Jayatilake, Jan; Malhotra, Raman

2016-12-01

Operating theatre utilization has become the principal measure of NHS operating theatre service performance. We analysed data from oculoplastic theatres in a tertiary centre to identify factors influencing theatre efficiency. We conducted three audits on operating theatre utilization in 2011, 2014 and 2015. Data was collected from real time information entered into the hospital database, including time of arrival, induction, first cut and close of operation. The primary outcome measure was the operating list utilization rate, a combined value of anaesthetic and surgical time as a proportion of the total planned session time. The initial 2011 audit recorded an operating list utilization rate of 81.2%. However, this dropped to 64.5% in 2014 following new management and a move to a new theatre suite. Analysis of the factors contributing to poor theatre efficiency led to changes that streamlined the patient pathway, including standardized case scheduling and reducing staggered patient arrival. A 2015 reaudit analyzing the effects of these changes demonstrated an increase in the operating list utilization rate to 78%. It was significantly higher (p < 0.01) for whole-day lists (85%) compared to half-day lists (75%), suggesting that whole-day lists were more efficient. Operating theatres are a valuable resource and the factors affecting theatre efficiency within our unit are common and will be relevant to units elsewhere. Correcting them can lead to significant improvements in patient care. Data from this study may provide a benchmark for other units in the United Kingdom.

Validating YouTube Factors Affecting Learning Performance

NASA Astrophysics Data System (ADS)

Pratama, Yoga; Hartanto, Rudy; Suning Kusumawardani, Sri

2018-03-01

YouTube is often used as a companion medium or a learning supplement. One of the educational places that often uses is Jogja Audio School (JAS) which focuses on music production education. Music production is a difficult material to learn, especially at the audio mastering. With tutorial contents from YouTube, students find it easier to learn and understand audio mastering and improved their learning performance. This study aims to validate the role of YouTube as a medium of learning in improving student’s learning performance by looking at the factors that affect student learning performance. The sample involves 100 respondents from JAS at audio mastering level. The results showed that student learning performance increases seen from factors that have a significant influence of motivation, instructional content, and YouTube usefulness. Overall findings suggest that YouTube has a important role to student learning performance in music production education and as an innovative and efficient learning medium.

High-efficiency photovoltaic technology including thermoelectric generation

NASA Astrophysics Data System (ADS)

Fisac, Miguel; Villasevil, Francesc X.; López, Antonio M.

2014-04-01

Nowadays, photovoltaic solar energy is a clean and reliable source for producing electric power. Most photovoltaic systems have been designed and built up for use in applications with low power requirements. The efficiency of solar cells is quite low, obtaining best results in monocrystalline silicon structures, with an efficiency of about 18%. When temperature rises, photovoltaic cell efficiency decreases, given that the short-circuit current is slightly increased, and the open-circuit voltage, fill factor and power output are reduced. To ensure that this does not affect performance, this paper describes how to interconnect photovoltaic and thermoelectric technology into a single structure. The temperature gradient in the solar panel is used to supply thermoelectric cells, which generate electricity, achieving a positive contribution to the total balance of the complete system.

Development of an efficient regeneration and transformation method for the new potential oilseed crop Lepidium campestre

PubMed Central

2013-01-01

Background Lepidium campestre is an undomesticated oilseed species with a great potential to become a new crop for both food and industrial feedstocks production. Genetic modification is needed for further improving the oil quantity and quality of Lepidium. Studies on in vitro shoot regeneration of Lepidium are very limited and there is no transformation protocol available. Results We have investigated the effects of different factors, especially the type, concentration and combination of plant growth regulators (PGRs) on in vitro shoot regeneration of Lepidium. The results showed that the 2,4-D treatment was crucial to shoot regeneration from different explants. The duration of 2,4-D exposure between 2-4 days did not show significant difference in shoot regeneration, while the effect of 2,4-D concentration varied greatly depending on the type of explants and cytokinins used, for example, the low concentration of 2,4-D combined with TDZ significantly increased the regeneration frequency of hypocotyls. Cotyledon and hypocotyl explants responded differently to cytokinin, for example, TDZ was more effective than zeatin in promoting shoot regeneration from hypocotyls, but did not affect the regeneration of cotyledons which was more affected by high concentration of zeatin. The results also showed that NAA was not effective for shoot regeneration. Germination in light increased the regeneration frequency compared to that in dark. After optimization of the different conditions, an efficient regeneration protocol was developed with the regeneration efficiency of 92.7%. Using this protocol, the transformation frequency of 6% in average was achieved. The presence of transgenes in the transgenic lines was confirmed by GUS staining, PCR and Southern blot analyses. Conclusion Through systematic investigation of important factors affecting in vitro shoot regeneration, we have developed an efficient regeneration and transformation protocol for the genetic modification of Lepidium campestre. The method may also be applied to the related species. PMID:23937221

The Efficiency and Budgeting of Public Hospitals: Case Study of Iran

PubMed Central

Yusefzadeh, Hasan; Ghaderi, Hossein; Bagherzade, Rafat; Barouni, Mohsen

2013-01-01

Background Hospitals are the most costly and important components of any health care system, so it is important to know their economic values, pay attention to their efficiency and consider factors affecting them. Objective The aim of this study was to assess the technical scale and economic efficiency of hospitals in the West Azerbaijan province of Iran, for which Data Envelopment Analysis (DEA) was used to propose a model for operational budgeting. Materials and Methods This study was a descriptive-analysis that was conducted in 2009 and had three inputs and two outputs. Deap2, 1 software was used for data analysis. Slack and radial movements and surplus of inputs were calculated for selected hospitals. Finally, a model was proposed for performance-based budgeting of hospitals and health sectors using the DEA technique. Results The average scores of technical efficiency, pure technical efficiency (managerial efficiency) and scale efficiency of hospitals were 0.584, 0.782 and 0.771, respectively. In other words the capacity of efficiency promotion in hospitals without any increase in costs and with the same amount of inputs was about 41.5%. Only four hospitals among all hospitals had the maximum level of technical efficiency. Moreover, surplus production factors were evident in these hospitals. Conclusions Reduction of surplus production factors through comprehensive planning based on the results of the Data Envelopment Analysis can play a major role in cost reduction of hospitals and health sectors. In hospitals with a technical efficiency score of less than one, the original and projected values of inputs were different; resulting in a surplus. Hence, these hospitals should reduce their values of inputs to achieve maximum efficiency and optimal performance. The results of this method was applied to hospitals a benchmark for making decisions about resource allocation; linking budgets to performance results; and controlling and improving hospitals performance. PMID:24349726

Lengths of Orthologous Prokaryotic Proteins Are Affected by Evolutionary Factors

PubMed Central

Tatarinova, Tatiana; Dien Bard, Jennifer; Cohen, Irit

2015-01-01

Proteins of the same functional family (for example, kinases) may have significantly different lengths. It is an open question whether such variation in length is random or it appears as a response to some unknown evolutionary driving factors. The main purpose of this paper is to demonstrate existence of factors affecting prokaryotic gene lengths. We believe that the ranking of genomes according to lengths of their genes, followed by the calculation of coefficients of association between genome rank and genome property, is a reasonable approach in revealing such evolutionary driving factors. As we demonstrated earlier, our chosen approach, Bubble-sort, combines stability, accuracy, and computational efficiency as compared to other ranking methods. Application of Bubble Sort to the set of 1390 prokaryotic genomes confirmed that genes of Archaeal species are generally shorter than Bacterial ones. We observed that gene lengths are affected by various factors: within each domain, different phyla have preferences for short or long genes; thermophiles tend to have shorter genes than the soil-dwellers; halophiles tend to have longer genes. We also found that species with overrepresentation of cytosines and guanines in the third position of the codon (GC3 content) tend to have longer genes than species with low GC3 content. PMID:26114113

Lengths of Orthologous Prokaryotic Proteins Are Affected by Evolutionary Factors.

PubMed

Tatarinova, Tatiana; Salih, Bilal; Dien Bard, Jennifer; Cohen, Irit; Bolshoy, Alexander

2015-01-01

Proteins of the same functional family (for example, kinases) may have significantly different lengths. It is an open question whether such variation in length is random or it appears as a response to some unknown evolutionary driving factors. The main purpose of this paper is to demonstrate existence of factors affecting prokaryotic gene lengths. We believe that the ranking of genomes according to lengths of their genes, followed by the calculation of coefficients of association between genome rank and genome property, is a reasonable approach in revealing such evolutionary driving factors. As we demonstrated earlier, our chosen approach, Bubble-sort, combines stability, accuracy, and computational efficiency as compared to other ranking methods. Application of Bubble Sort to the set of 1390 prokaryotic genomes confirmed that genes of Archaeal species are generally shorter than Bacterial ones. We observed that gene lengths are affected by various factors: within each domain, different phyla have preferences for short or long genes; thermophiles tend to have shorter genes than the soil-dwellers; halophiles tend to have longer genes. We also found that species with overrepresentation of cytosines and guanines in the third position of the codon (GC3 content) tend to have longer genes than species with low GC3 content.

Decreasing Cognitive Load for Learners: Strategy of Web-Based Foreign Language Learning

ERIC Educational Resources Information Center

Zhang, Jianfeng

2013-01-01

Cognitive load is one of the important factors that influence the effectiveness and efficiency of web-based foreign language learning. Cognitive load theory assumes that human's cognitive capacity in working memory is limited and if it overloads, learning will be hampered, so that high level of cognitive load can affect the performance of learning…

An Evaluation of Organizational and Experience Factors Affecting the Perceived Transfer of U.S. Air Force Basic Combat Skills Training

DTIC Science & Technology

2007-03-01

to determine the most efficient way to perform a task (Gibson, Ivancevich , Donnelly & Konopaske, 2006). In a series of articles published in 1959...Gibson, J. L., Ivancevich , J. M., Donnelly, Jr., J. H., & Konopaske, R. (2006). Organizations: Behavior, Structure, Processes. New York: McGraw

Factors Influencing Computer Anxiety and Its Impact on E-Learning Effectiveness: A Review of Literature

ERIC Educational Resources Information Center

Chien, Tien-Chen

2008-01-01

Computer is not only a powerful technology for managing information and enhancing productivity, but also an efficient tool for education and training. Computer anxiety can be one of the major problems that affect the effectiveness of learning. Through analyzing related literature, this study describes the phenomenon of computer anxiety,…

Real-Time Imaging of Plant Cell Wall Structure at Nanometer Scale, with Respect to Cellulase Accessibility and Degradation Kinetics (Presentation)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ding, S. Y.

Presentation on real-time imaging of plant cell wall structure at nanometer scale. Objectives are to develop tools to measure biomass at the nanometer scale; elucidate the molecular bases of biomass deconstruction; and identify factors that affect the conversion efficiency of biomass-to-biofuels.

Measurement of Ozone Emission and Particle Removal Rates from Portable Air Purifiers

ERIC Educational Resources Information Center

Mang, Stephen A.; Walser, Maggie L.; Nizkorodov, Sergey A.; Laux, John M.

2009-01-01

Portable air purifiers are popular consumer items, especially in areas with poor air quality. Unfortunately, most users of these air purifiers have minimal understanding of the factors affecting their efficiency in typical indoor settings. Emission of the air pollutant ozone (O[subscript 3]) by certain air purifiers is of particular concern. In an…

Mitigation and treatment of pollutants from railway and highway runoff by pocket wetland system; A case study.

PubMed

Senduran, Cem; Gunes, Kemal; Topaloglu, Duygu; Dede, Omer Hulusi; Masi, Fabio; Kucukosmanoglu, Ozen Arli

2018-08-01

This study performed in Sapanca Lake catchment area, used as a drinking water resource. Two highways located at northern and southern shores, and a railway at its south are significant sources of pollution. As a possible solution for protecting water quality a pocket wetland constructed and operated. Performances statistically interpreted by Spearman's Correlation test and univariate analysis of variance on collected data. The mean removal efficiencies obtaited were 52% (TSS), 4% (Nitrate), 26% (TN), -5% (TOC), 63% (TP), 4.5% (Chloride), 3% (Sulfate), 33% (Cr), 39% (Co), -19.5% (Ni), 7% (Cu), 55% (Zn), 36% (As), 38% (Cd) and 18% (Pb). TSS removal was in positive significant medium correlation with Co, Cu, Zn, and Pb removal respectively (p < 0.05). Other statistically significant positive high correlations calculated between removal efficiency of Nitrate-TN, Chloride-Sulfate, Cr-Co-Cu-As-Cd. According to ANOVA and Kruskal-Wallis test results, removal efficiencies of TSS and TOC partially affected by different temperature (p < 0.1 for TSS and p < 0.05 for TOC) and pH ranges (p < 0.1 for both removal efficiencies), TP removal efficiency significantly affected by different pH ranges (p < 0.001), and Chloride and Sulfate removal efficiencies were significantly (p < 0.001) affected by different temperature ranges. Regardless of geographical location and climatic factors, pocket wetland systems can be relied upon for minimizing heavy metals such as Cr, Co, Zn, As, Cd and Pb and critical pollutants such as TP and TSS caused by highway runoff. Copyright © 2018 Elsevier Ltd. All rights reserved.

The impact of managed care penetration and hospital quality on efficiency in hospital staffing.

PubMed

Mobley, Lee R; Magnussen, Jon

2002-01-01

The state of California has recently mandated minimum nurse-staffing ratios, raising concerns about possible affects on hospital efficiency. In this study, we examine how market factors and quality were related to staffing levels in California hospitals in 1995 (prior to implementation of the new law). We are particularly interested in the affect of managed care penetration on this aspect of hospital efficiency because the call to legislative action was predicated on fears that hospitals were reducing staffing below optimal levels in response to managed care pressures. We derive a unique measure of excess staffing in hospitals based on a data envelopment analysis (DEA) production function model, which explicitly includes ancillary care among the inputs and outputs. This careful specification of production is important because ancillary care use has risen relative to daily hospital services, with the spread of managed care and advances in medical technology. We find that market share (adjusted for size) and market concentration are the major determinants of excess staffing while managed care penetration is insignificant. We also find that poor quality (outcomes worse than expected) is associated with less efficient staffing. These findings suggest that the larger, more efficient urban hospitals will be penalized more heavily under binding staffing ratios than smaller, less-urban hospitals.

[The ways in which variations in space and atmospheric factors act upon the biosphere and humans].

PubMed

Chernogor, L F

2010-01-01

The system analysis is validated to be an efficient means for studying the channels through which variations in space and tropospheric weather affect the biosphere (humans). The basics of the system analysis paradigm are presented. The causes of variations in space and tropospheric weather are determined, and the interrelations between them are demonstrated. The ways in which these variations affect the biosphere (humans) are discussed. Aperiodic and quasi-periodic disturbances in the physical fields that influence the biosphere (humans) are intercompared.

Progress in dimethacrylate-based dental composite technology and curing efficiency.

PubMed

Leprince, Julian G; Palin, William M; Hadis, Mohammed A; Devaux, Jacques; Leloup, Gaetane

2013-02-01

This work aims to review the key factors affecting the polymerization efficiency of light-activated resin-based composites. The different properties and methods used to evaluate polymerization efficiency will also be critically appraised with focus on the developments in dental photopolymer technology and how recent advances have attempted to improve the shortcomings of contemporary resin composites. Apart from the classical literature on the subject, the review focused in particular on papers published since 2009. The literature research was performed in Scopus with the terms "dental resin OR dimethacrylate". The list was screened and all papers relevant to the objectives of this work were included. Though new monomer technologies have been developed and some of them already introduced to the dental market, dimethacrylate-based composites still currently represent the vast majority of commercially available materials for direct restoration. The photopolymerization of resin-based composites has been the subject of numerous publications, which have highlighted the major impact of the setting process on material properties and quality of the final restoration. Many factors affect the polymerization efficiency, be they intrinsic; photoinitiator type and concentration, viscosity (co-monomer composition and ratio, filler content) and optical properties, or extrinsic; light type and spectrum, irradiation parameters (radiant energy, time and irradiance), curing modes, temperature and light guide tip positioning. : This review further highlights the apparent need for a more informative approach by manufacturers to relay appropriate information in order for dentists to optimize material properties of resin composites used in daily practice. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Understanding the human dimensions of a sustainable energy transition.

PubMed

Steg, Linda; Perlaviciute, Goda; van der Werff, Ellen

2015-01-01

Global climate change threatens the health, economic prospects, and basic food and water sources of people. A wide range of changes in household energy behavior is needed to realize a sustainable energy transition. We propose a general framework to understand and encourage sustainable energy behaviors, comprising four key issues. First, we need to identify which behaviors need to be changed. A sustainable energy transition involves changes in a wide range of energy behaviors, including the adoption of sustainable energy sources and energy-efficient technology, investments in energy efficiency measures in buildings, and changes in direct and indirect energy use behavior. Second, we need to understand which factors underlie these different types of sustainable energy behaviors. We discuss three main factors that influence sustainable energy behaviors: knowledge, motivations, and contextual factors. Third, we need to test the effects of interventions aimed to promote sustainable energy behaviors. Interventions can be aimed at changing the actual costs and benefits of behavior, or at changing people's perceptions and evaluations of different costs and benefits of behavioral options. Fourth, it is important to understand which factors affect the acceptability of energy policies and energy systems changes. We discuss important findings from psychological studies on these four topics, and propose a research agenda to further explore these topics. We emphasize the need of an integrated approach in studying the human dimensions of a sustainable energy transition that increases our understanding of which general factors affect a wide range of energy behaviors as well as the acceptability of different energy policies and energy system changes.

Understanding the human dimensions of a sustainable energy transition

PubMed Central

Steg, Linda; Perlaviciute, Goda; van der Werff, Ellen

2015-01-01

Global climate change threatens the health, economic prospects, and basic food and water sources of people. A wide range of changes in household energy behavior is needed to realize a sustainable energy transition. We propose a general framework to understand and encourage sustainable energy behaviors, comprising four key issues. First, we need to identify which behaviors need to be changed. A sustainable energy transition involves changes in a wide range of energy behaviors, including the adoption of sustainable energy sources and energy-efficient technology, investments in energy efficiency measures in buildings, and changes in direct and indirect energy use behavior. Second, we need to understand which factors underlie these different types of sustainable energy behaviors. We discuss three main factors that influence sustainable energy behaviors: knowledge, motivations, and contextual factors. Third, we need to test the effects of interventions aimed to promote sustainable energy behaviors. Interventions can be aimed at changing the actual costs and benefits of behavior, or at changing people’s perceptions and evaluations of different costs and benefits of behavioral options. Fourth, it is important to understand which factors affect the acceptability of energy policies and energy systems changes. We discuss important findings from psychological studies on these four topics, and propose a research agenda to further explore these topics. We emphasize the need of an integrated approach in studying the human dimensions of a sustainable energy transition that increases our understanding of which general factors affect a wide range of energy behaviors as well as the acceptability of different energy policies and energy system changes. PMID:26136705

Post-evaluation of a ground source heat pump system for residential space heating in Shanghai China

NASA Astrophysics Data System (ADS)

Lei, Y.; Tan, H. W.; Wang, L. Z.

2017-11-01

Residents of Southern China are increasingly concerned about the space heating in winter. The chief aim of the present work is to find a cost-effective way for residential space heating in Shanghai, one of the biggest city in south China. Economic and energy efficiency of three residential space heating ways, including ground source heat pump (GSHP), air source heat pump (ASHP) and wall-hung gas boiler (WHGB), are assessed based on Long-term measured data. The results show that the heat consumption of the building is 120 kWh/m2/y during the heating season, and the seasonal energy efficiency ratio (SEER) of the GSHP, ASHP and WHGB systems are 3.27, 2.30, 0.88 respectively. Compared to ASHP and WHGB, energy savings of GSHP during the heating season are 6.2 kgce/(m2.y) and 2.2 kgce/(m2.y), and the payback period of GSHP are 13.3 and 7.6 years respectively. The sensitivity analysis of various factors that affect the payback period is carried out, and the results suggest that SEER is the most critical factor affecting the feasibility of ground source heat pump application, followed by building load factor and energy price factor. These findings of the research have led the author to the conclusion that ground source heat pump for residential space heating in Shanghai is a good alternative, which can achieve significant energy saving benefits, and a good system design and operation management are key factors that can shorten the payback period.

Efficiency limit factor analysis for the Francis-99 hydraulic turbine

NASA Astrophysics Data System (ADS)

Zeng, Y.; Zhang, L. X.; Guo, J. P.; Guo, Y. K.; Pan, Q. L.; Qian, J.

2017-01-01

The energy loss in hydraulic turbine is the most direct factor that affects the efficiency of the hydraulic turbine. Based on the analysis theory of inner energy loss of hydraulic turbine, combining the measurement data of the Francis-99, this paper calculates characteristic parameters of inner energy loss of the hydraulic turbine, and establishes the calculation model of the hydraulic turbine power. Taken the start-up test conditions given by Francis-99 as case, characteristics of the inner energy of the hydraulic turbine in transient and transformation law are researched. Further, analyzing mechanical friction in hydraulic turbine, we think that main ingredients of mechanical friction loss is the rotation friction loss between rotating runner and water body, and defined as the inner mechanical friction loss. The calculation method of the inner mechanical friction loss is given roughly. Our purpose is that explore and research the method and way increasing transformation efficiency of water flow by means of analysis energy losses in hydraulic turbine.

Tree diversity affects chlorophyll a fluorescence and other leaf traits of tree species in a boreal forest.

PubMed

Pollastrini, Martina; Nogales, Ana Garcia; Benavides, Raquel; Bonal, Damien; Finer, Leena; Fotelli, Mariangela; Gessler, Arthur; Grossiord, Charlotte; Radoglou, Kalliopi; Strasser, Reto J; Bussotti, Filippo

2017-02-01

An assemblage of tree species with different crown properties creates heterogeneous environments at the canopy level. Changes of functional leaf traits are expected, especially those related to light interception and photosynthesis. Chlorophyll a fluorescence (ChlF) properties in dark-adapted leaves, specific leaf area, leaf nitrogen content (N) and carbon isotope composition (δ13C) were measured on Picea abies (L.) H.Karst., Pinus sylvestris L. and Betula pendula Roth. in monospecific and mixed boreal forests in Europe, in order to test whether they were affected by stand species richness and composition. Photosynthetic efficiency, assessed by induced emission of leaf ChlF, was positively influenced in B. pendula by species richness, whereas P. abies showed higher photosynthetic efficiency in monospecific stands. Pinus sylvestris had different responses when it coexisted with P. abies or B. pendula. The presence of B. pendula, but not of P. abies, in the forest had a positive effect on the efficiency of photosynthetic electron transport and N in P. sylvestris needles, and the photosynthetic responses were positively correlated with an increase of leaf δ13C. These effects on P. sylvestris may be related to high light availability at the canopy level due to the less dense canopy of B. pendula. The different light requirements of coexisting species was the most important factor affecting the distribution of foliage in the canopy, driving the physiological responses of the mixed species. Future research directions claim to enhance the informative potential of the methods to analyse the responses of pure and mixed forests to environmental factors, including a broader set of plant species' functional traits and physiological responses. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Factor structure and diagnostic efficiency of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria for avoidant personality disorder in Hispanic men and women with substance use disorders.

PubMed

Becker, Daniel F; Añez, Luis Miguel; Paris, Manuel; Bedregal, Luis; Grilo, Carlos M

2009-01-01

This study examined the internal consistency, factor structure, and diagnostic efficiency of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), criteria for avoidant personality disorder (AVPD) and the extent to which these metrics may be affected by sex. Subjects were 130 monolingual Hispanic adults (90 men, 40 women) who had been admitted to a specialty clinic that provides psychiatric and substance abuse services to Spanish-speaking patients. All were reliably assessed with the Spanish-Language Version of the Diagnostic Interview for DSM-IV Personality Disorders. The AVPD diagnosis was determined by the best-estimate method. After evaluating internal consistency of the AVPD criterion set, an exploratory factor analysis was performed using principal components extraction. Afterward, diagnostic efficiency indices were calculated for all AVPD criteria. Subsequent analyses examined men and women separately. For the overall group, internal consistency of AVPD criteria was good. Exploratory factor analysis revealed a 1-factor solution (accounting for 70% of the variance), supporting the unidimensionality of the AVPD criterion set. The best inclusion criterion was "reluctance to take risks," whereas "interpersonally inhibited" was the best exclusion criterion and the best predictor overall. When men and women were examined separately, similar results were obtained for both internal consistency and factor structure, with slight variations noted between sexes in the patterning of diagnostic efficiency indices. These psychometric findings, which were similar for men and women, support the construct validity of the DSM-IV criteria for AVPD and may also have implications for the treatment of this particular clinical population.

Factors influencing specialist outreach and support services to rural populations in the Eden and Central Karoo districts of the Western Cape.

PubMed

Schoevers, Johan; Jenkins, Louis

2015-04-21

Access to health care often depends on where one lives. Rural populations have significantly poorer health outcomes than their urban counterparts. Specialist outreach to rural communities is one way of improving access to care. A multifaceted style of outreach improves access and health outcomes, whilst a shifted outpatients style only improves access. In principle, stakeholders agree that specialist outreach and support (O&S) to rural populations is necessary. In practice, however, factors influence whether or not O&S reaches its goals, affecting sustainability.Aim and setting: Our aim was to better understand factors associated with the success or failure of specialist O&S to rural populations in the Eden and Central Karoo districts in the Western Cape. An anonymous parallel three-stage Delphi process was followed to obtain consensus in a specialist and district hospital panel. Twenty eight specialist and 31 district hospital experts were invited, with response rates of 60.7%-71.4% and 58.1%-74.2% respectively across the three rounds. Relationships, communication and planning were found to be factors feeding into a service delivery versus capacity building tension, which affects the efficiency of O&S. The success of the O&S programme is dependent on a site-specific model that is acceptable to both the outreaching specialists and the hosting district hospital. Good communication, constructive feedback and improved planning may improve relationships and efficiency, which might lead to a more sustainable and mutually beneficial O&S system.

Efficiency Management in Spaceflight Systems

NASA Technical Reports Server (NTRS)

Murphy, Karen

2016-01-01

Efficiency in spaceflight is often approached as “faster, better, cheaper – pick two”. The high levels of performance and reliability required for each mission suggest that planners can only control for two of the three. True efficiency comes by optimizing a system across all three parameters. The functional processes of spaceflight become technical requirements on three operational groups during mission planning: payload, vehicle, and launch operations. Given the interrelationships among the functions performed by the operational groups, optimizing function resources from one operational group to the others affects the efficiency of those groups and therefore the mission overall. This paper helps outline this framework and creates a context in which to understand the effects of resource trades on the overall system, improving the efficiency of the operational groups and the mission as a whole. This allows insight into and optimization of the controlling factors earlier in the mission planning stage.

Factors Involved in Access and Utilization of Adult Hearing Healthcare: A Systematic Review

PubMed Central

Barnett, Margaret; Hixon, Brian; Okwiri, Neville; Irungu, Catherine; Ayugi, John; Thompson, Robin; Shinn, Jennifer B.; Bush, Matthew L.

2016-01-01

Objective/Hypothesis Hearing loss is a public health concern yet hearing healthcare disparities exist and influence utilization of rehabilitation services. The objective of this review was to systematically analyze the published literature on motivators, barriers, and compliance factors affecting adult patient access and utilization of hearing rehabilitation healthcare. Data Sources and Study Eligibility Criteria Pubmed, PsychINFO, CINAHL, Web of Science were searched for relevant articles. Eligible studies were those containing original, peer-reviewed research in English pertaining to factors affecting adult hearing healthcare access and utilization of hearing aids and cochlear implantation. The search encompassed 1990-2015. Study Appraisal and Synthesis Methods Two investigators independently reviewed all articles and extracted data. Specific variables regarding access to care and compliance to recommended care were extracted from each study. Results Thirty articles were reviewed. The factors affecting access and utilization of hearing rehabilitation could be classified into motivators, barriers, and compliance in treatment or device use. The key motivators to seek care include degree of hearing loss, self-efficacy, family support, and self-recognition of hearing loss. The primary barriers to care were financial limitations, stigma of hearing devices, inconvenience, competing chronic health problems, and unrealistic expectations. Compliance is most affected by self-efficacy, education level, and engagement in the rehabilition process. Conclusion Accessing hearing healthcare is complicated by multiple factors. Considering the current climate in healthcare policy and legislation towards improved access of care, a deeper understanding of motivators, barriers and compliance factors can aid in delivery of effective and efficient hearing healthcare. PMID:27545324

Factors involved in access and utilization of adult hearing healthcare: A systematic review.

PubMed

Barnett, Margaret; Hixon, Brian; Okwiri, Neville; Irungu, Catherine; Ayugi, John; Thompson, Robin; Shinn, Jennifer B; Bush, Matthew L

2017-05-01

Hearing loss is a public health concern, yet hearing healthcare disparities exist and influence utilization of rehabilitation services. The objective of this review was to systematically analyze the published literature on motivators, barriers, and compliance factors affecting adult patient access and utilization of hearing rehabilitation healthcare. Pubmed, PsychINFO, CINAHL, and Web of Science were searched for relevant articles. Eligible studies were those containing original, peer-reviewed research in English pertaining to factors affecting adult hearing healthcare access and utilization of hearing aids and cochlear implantation. The search encompassed 1990 to 2015. Two investigators independently reviewed all articles and extracted data. Specific variables regarding access to care and compliance to recommended care were extracted from each study. Thirty articles were reviewed. The factors affecting access and utilization of hearing rehabilitation could be classified into motivators, barriers, and compliance in treatment or device use. The key motivators to seek care include degree of hearing loss, self-efficacy, family support, and self-recognition of hearing loss. The primary barriers to care were financial limitations, stigma of hearing devices, inconvenience, competing chronic health problems, and unrealistic expectations. Compliance is most affected by self-efficacy, education level, and engagement in the rehabilitation process. Accessing hearing healthcare is complicated by multiple factors. Considering the current climate in healthcare policy and legislation toward improved access of care, a deeper understanding of motivators, barriers, and compliance factors can aid in delivery of effective and efficient hearing healthcare. Laryngoscope, 127:1187-1194, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Pathogen and host genotype differently affect pathogen fitness through their effects on different life-history stages.

PubMed

Bruns, Emily; Carson, Martin; May, Georgiana

2012-08-02

Adaptation of pathogens to their hosts depends critically on factors affecting pathogen reproductive rate. While pathogen reproduction is the end result of an intricate interaction between host and pathogen, the relative contributions of host and pathogen genotype to variation in pathogen life history within the host are not well understood. Untangling these contributions allows us to identify traits with sufficient genetic variation for selection to act and to identify mechanisms of coevolution between pathogens and their hosts. We investigated the effects of pathogen and host genotype on three life-history components of pathogen fitness; infection efficiency, latent period, and sporulation capacity, in the oat crown rust fungus, Puccinia coronata f.sp. avenae, as it infects oats (Avena sativa). We show that both pathogen and host genotype significantly affect total spore production but do so through their effects on different life-history stages. Pathogen genotype has the strongest effect on the early stage of infection efficiency, while host genotype most strongly affects the later life-history stages of latent period and sporulation capacity. In addition, host genotype affected the relationship between pathogen density and the later life-history traits of latent period and sporulation capacity. We did not find evidence of pathogen-by-host genotypic (GxG) interactions. Our results illustrate mechanisms by which variation in host populations will affect the evolution of pathogen life history. Results show that different pathogen life-history stages have the potential to respond differently to selection by host or pathogen genotype and suggest mechanisms of antagonistic coevolution. Pathogen populations may adapt to host genotypes through increased infection efficiency while their plant hosts may adapt by limiting the later stages of pathogen growth and spore production within the host.

Hydrologic, abiotic and biotic interactions: plant density, windspeed, leaf size and groundwater all affect oak water use efficiency

Treesearch

Darin J. Law; Deborah M. Finch

2011-01-01

Plant water use in drylands can be complex due to variation in hydrologic, abiotic and biotic factors, particularly near ephemeral or intermittent streams. Plant use of groundwater may be important but is usually uncertain. Disturbances like fire contribute to complex spatiotemporal heterogeneity. Improved understanding of how such hydrologic, abiotic, and biotic...

Factors affecting behavioral changes in response to road fees : some analyses of the effect of attitudes, transit access and fuel efficiency on changes in miles driven, final report, February 2009.

DOT National Transportation Integrated Search

2009-02-01

The Oregon Department of Transportation tested a system to collect a vehicle-based mileage fee as a replacement for the Oregon gas tax. This : project reports on additional analysis of the data from that experiment. Subjects include analysis of the c...

Prediction of Work Efficiency in Early Adolescence under the Effects of Noise

ERIC Educational Resources Information Center

Fosnaric, Samo; Planinsec, Jurij

2008-01-01

This is a short summary of research on how different stress factors in the work environment (climate, light, noise) affect work performance of early adolescents. Due to the complexity of the measurements, the research consisted of a small sample of male adolescents (N = 20); average age 13.5 years (SD = 0.25). Tasks were used which demanded…

Catalytic Hydroamination of Alkynes and Norbornene with Neutral and Cationic Tantalum Imido Complexes

PubMed Central

Anderson, Laura L.; Arnold, John; Bergman, Robert G.

2005-01-01

Several tantalum imido complexes have been synthesized and shown to efficiently catalyze the hydroamination of internal and terminal alkynes. An unusual hydroamination/hydroarylation reaction of norbornene catalyzed by a highly electrophilic cationic tantalum imido complex is also reported. Factors affecting catalyst activity and selectivity are discussed along with mechanistic insights gained from stoichiometric reactions. PMID:15255680

Air regenerating and conditioning

NASA Technical Reports Server (NTRS)

Grishayenkov, B. G.

1975-01-01

Various physicochemical methods of regenerating and conditioning air for spacecraft are described with emphasis on conditions which affect efficiency of the system. Life support systems used in closed, hermetically sealed environments are discussed with references to actual application in the Soviet Soyuz and Voskhod manned spacecraft. Temperature and humidity control, removal of carbon dioxide, oxygen regeneration, and removal of bacteria and viruses are among the factors considered.

Performance Analysis and Optimization on the UCLA Parallel Atmospheric General Circulation Model Code

NASA Technical Reports Server (NTRS)

Lou, John; Ferraro, Robert; Farrara, John; Mechoso, Carlos

1996-01-01

An analysis is presented of several factors influencing the performance of a parallel implementation of the UCLA atmospheric general circulation model (AGCM) on massively parallel computer systems. Several modificaitons to the original parallel AGCM code aimed at improving its numerical efficiency, interprocessor communication cost, load-balance and issues affecting single-node code performance are discussed.

Innovation in the collective brain

PubMed Central

Muthukrishna, Michael; Henrich, Joseph

2016-01-01

Innovation is often assumed to be the work of a talented few, whose products are passed on to the masses. Here, we argue that innovations are instead an emergent property of our species' cultural learning abilities, applied within our societies and social networks. Our societies and social networks act as collective brains. We outline how many human brains, which evolved primarily for the acquisition of culture, together beget a collective brain. Within these collective brains, the three main sources of innovation are serendipity, recombination and incremental improvement. We argue that rates of innovation are heavily influenced by (i) sociality, (ii) transmission fidelity, and (iii) cultural variance. We discuss some of the forces that affect these factors. These factors can also shape each other. For example, we provide preliminary evidence that transmission efficiency is affected by sociality—languages with more speakers are more efficient. We argue that collective brains can make each of their constituent cultural brains more innovative. This perspective sheds light on traits, such as IQ, that have been implicated in innovation. A collective brain perspective can help us understand otherwise puzzling findings in the IQ literature, including group differences, heritability differences and the dramatic increase in IQ test scores over time. PMID:26926282

Agrobacterium tumefaciens-mediated transformation of Campanula carpatica: factors affecting transformation and regeneration of transgenic shoots.

PubMed

Sriskandarajah, Sridevy; Frello, Stefan; Jørgensen, Kirsten; Serek, Margrethe

2004-08-01

An efficient transformation system for Campanula carpatica was developed using Agrobacterium tumefaciens strains LBA4404 (harbouring the plasmid pBI121), and AGL0 (harbouring the plasmid pBEO210). This is the first report on the transformation of C. carpatica. Various factors affecting the transformation efficiency and subsequent regeneration were identified. The age of seedlings from which the explants for transformation studies were taken, and the growth conditions under which the seedlings were grown had a significant influence on the production of transformed shoots. Hypocotyls taken from 12-day-old seedlings grown in the dark were the most productive, with up to 25% of hypocotyls producing transformed shoots. Explants taken from 5-week-old seedlings produced only transformed callus. The medium used for co-cultivation and incubation also had a significant influence on transformation frequency and shoot regeneration. The cultivar "Blue Uniform" was more responsive than "White Uniform". Both bacterial strains and plasmids were equally effective in producing transformed tissue. Transformed shoots were selected on kanamycin medium, and the presence of the uidA and nptII genes in those selected shoots was confirmed by beta-glucuronidase and ELISA analyses, respectively.

Innovation in the collective brain.

PubMed

Muthukrishna, Michael; Henrich, Joseph

2016-03-19

Innovation is often assumed to be the work of a talented few, whose products are passed on to the masses. Here, we argue that innovations are instead an emergent property of our species' cultural learning abilities, applied within our societies and social networks. Our societies and social networks act as collective brains. We outline how many human brains, which evolved primarily for the acquisition of culture, together beget a collective brain. Within these collective brains, the three main sources of innovation are serendipity, recombination and incremental improvement. We argue that rates of innovation are heavily influenced by (i) sociality, (ii) transmission fidelity, and (iii) cultural variance. We discuss some of the forces that affect these factors. These factors can also shape each other. For example, we provide preliminary evidence that transmission efficiency is affected by sociality--languages with more speakers are more efficient. We argue that collective brains can make each of their constituent cultural brains more innovative. This perspective sheds light on traits, such as IQ, that have been implicated in innovation. A collective brain perspective can help us understand otherwise puzzling findings in the IQ literature, including group differences, heritability differences and the dramatic increase in IQ test scores over time. © 2016 The Author(s).

Livestock production: recent trends, future prospects

PubMed Central

Thornton, Philip K.

2010-01-01

The livestock sector globally is highly dynamic. In developing countries, it is evolving in response to rapidly increasing demand for livestock products. In developed countries, demand for livestock products is stagnating, while many production systems are increasing their efficiency and environmental sustainability. Historical changes in the demand for livestock products have been largely driven by human population growth, income growth and urbanization and the production response in different livestock systems has been associated with science and technology as well as increases in animal numbers. In the future, production will increasingly be affected by competition for natural resources, particularly land and water, competition between food and feed and by the need to operate in a carbon-constrained economy. Developments in breeding, nutrition and animal health will continue to contribute to increasing potential production and further efficiency and genetic gains. Livestock production is likely to be increasingly affected by carbon constraints and environmental and animal welfare legislation. Demand for livestock products in the future could be heavily moderated by socio-economic factors such as human health concerns and changing socio-cultural values. There is considerable uncertainty as to how these factors will play out in different regions of the world in the coming decades. PMID:20713389

Human, donkey and cow milk differently affects energy efficiency and inflammatory state by modulating mitochondrial function and gut microbiota.

PubMed

Trinchese, Giovanna; Cavaliere, Gina; Canani, Roberto Berni; Matamoros, Sebastien; Bergamo, Paolo; De Filippo, Chiara; Aceto, Serena; Gaita, Marcello; Cerino, Pellegrino; Negri, Rossella; Greco, Luigi; Cani, Patrice D; Mollica, Maria Pina

2015-11-01

Different nutritional components are able, by modulating mitochondrial function and gut microbiota composition, to influence body composition, metabolic homeostasis and inflammatory state. In this study, we aimed to evaluate the effects produced by the supplementation of different milks on energy balance, inflammatory state, oxidative stress and antioxidant/detoxifying enzyme activities and to investigate the role of the mitochondrial efficiency and the gut microbiota in the regulation of metabolic functions in an animal model. We compared the intake of human milk, gold standard for infant nutrition, with equicaloric supplementation of donkey milk, the best substitute for newborns due to its nutritional properties, and cow milk, the primary marketed product. The results showed a hypolipidemic effect produced by donkey and human milk intake in parallel with enhanced mitochondrial activity/proton leakage. Reduced mitochondrial energy efficiency and proinflammatory signals (tumor necrosis factor α, interleukin-1 and lipopolysaccharide levels) were associated with a significant increase of antioxidants (total thiols) and detoxifying enzyme activities (glutathione-S-transferase, NADH quinone oxidoreductase) in donkey- and human milk-treated animals. The beneficial effects were attributable, at least in part, to the activation of the nuclear factor erythroid-2-related factor-2 pathway. Moreover, the metabolic benefits induced by human and donkey milk may be related to the modulation of gut microbiota. In fact, milk treatments uniquely affected the proportions of bacterial phyla and genera, and we hypothesized that the increased concentration of fecal butyrate in human and donkey milk-treated rats was related to the improved lipid and glucose metabolism and detoxifying activities. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Efficiency enhancement of ZnO nanostructure assisted Si solar cell based on fill factor enlargement and UV-blue spectral down-shifting

NASA Astrophysics Data System (ADS)

Gholizadeh, A.; Reyhani, A.; Parvin, P.; Mortazavi, S. Z.

2017-05-01

ZnO nanostructures (including nano-plates and nano-rods (NRs)) are grown in various temperatures and Ar/O2 flow rates using thermal chemical vapor deposition, which affect the structure, nano-plate/NR population, and the quality of ZnO nanostructures. X-ray diffraction (XRD) attests that the peak intensity of the crystallographic plane (1 0 0) is correlated to nano-plate abundance. Moreover, optical properties elucidate that the population of nano-plates in samples strongly affect the band gap, binding energy of the exciton, and UV-visible (UV-vis) absorption and spectral luminescence emissions. In fact, the exciton binding energy reduces from ~100 to 80 meV when the population of nano-plates increases in samples. Photovoltaic characteristics based on the drop-casting on Si solar cells reveals three dominant factors, namely, the equivalent series resistance, decreasing reflectance, and down-shifting, in order to scale up the absolute efficiency by 3%. As a consequence, the oxygen vacancies in ZnO nanostructures give rise to the down-shifting and increase of free-carriers, leading to a reduction in the equivalent series resistance and an enlargement of fill factor. To obtain a larger I sc, reduction of spectral reflectance is essential; however, the down-shifting process is shown to be dominant by lessening the surface electron-hole recombination rate over the UV-blue spectral range.

Factors Affecting Pheromone Production by the Pepper Weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae) and Collection Efficiency

PubMed Central

Eller, Fred J.; Palmquist, Debra E.

2014-01-01

Several factors affecting pheromone production by male pepper weevils, Anthonomus eugenii Cano (Coleoptera: Curculionidae) as well as collection efficiency were investigated. Factors studied included: porous polymer adsorbents (Tenax versus Super Q), male age, time of day, male density, and male diet. Super Q was found to be a superior adsorbent for the male-produced alcohols and geranic acid as well as the plant-produced E-β-ocimene. Pheromone production increased with male age up to about age 15 days old and then tapered off. Male pepper weevils produced the highest amount of pheromone between noon and 2 pm (i.e., 4 to 6 h after “lights on”) and were producing ca. 800 ng/h during this period. Thereafter, pheromone production decreased and was extremely low during the scotophase (i.e., ca. 12 ng/h). Male pepper weevil density had a significant effect on both release rate and pheromone composition. Pheromone production on a per male basis was highest for individual males and the percentage of geranic acid in the blend was lowest for individual males. Male pepper weevils produced only extremely low amounts of pheromone when feeding on artificial diet; however, they produced very high amounts when on fresh peppers. Together, this information will be useful in designing better attractant lures for pepper weevils. PMID:26462948

Determining major factors controlling phosphorus removal by promising adsorbents used for lake restoration: A linear mixed model approach.

PubMed

Funes, A; Martínez, F J; Álvarez-Manzaneda, I; Conde-Porcuna, J M; de Vicente, J; Guerrero, F; de Vicente, I

2018-05-17

Phosphorus (P) removal from lake/drainage waters by novel adsorbents may be affected by competitive substances naturally present in the aqueous media. Up to date, the effect of interfering substances has been studied basically on simple matrices (single-factor effects) or by applying basic statistical approaches when using natural lake water. In this study, we determined major factors controlling P removal efficiency in 20 aquatic ecosystems in the southeast Spain by using linear mixed models (LMMs). Two non-magnetic -CFH-12 ® and Phoslock ® - and two magnetic materials -hydrous lanthanum oxide loaded silica-coated magnetite (Fe-Si-La) and commercial zero-valent iron particles (FeHQ)- were tested to remove P at two adsorbent dosages. Results showed that the type of adsorbent, the adsorbent dosage and color of water (indicative of humic substances) are major factors controlling P removal efficiency. Differences in physico-chemical properties (i.e. surface charge or specific surface), composition and structure explain differences in maximum P adsorption capacity and performance of the adsorbents when competitive ions are present. The highest P removal efficiency, independently on whether the adsorbent dosage was low or high, were 85-100% for Phoslock and CFH-12 ® , 70-100% for Fe-Si-La and 0-15% for FeHQ. The low dosage of FeHQ, compared to previous studies, explained its low P removal efficiency. Although non-magnetic materials were the most efficient, magnetic adsorbents (especially Fe-Si-La) could be proposed for P removal as they can be recovered along with P and be reused, potentially making them more profitable in a long-term period. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of temperature and salinity on survival rate of cultured corals and photosynthetic efficiency of zooxanthellae in coral tissues

NASA Astrophysics Data System (ADS)

Kuanui, Pataporn; Chavanich, Suchana; Viyakarn, Voranop; Omori, Makoto; Lin, Chiahsin

2015-06-01

This study investigated the effects of temperature and salinity on growth, survival, and photosynthetic efficiency of three coral species, namely, Pocillopora damicornis, Acropora millepora and Platygyra sinensis of different ages (6 and 18 months old). The experimental corals were cultivated via sexual propagation. Colonies were exposed to 5 different temperatures (18, 23, 28, 33, and 38°C) and 5 different salinities (22, 27, 32, 37, and 42 psu). Results showed that temperature significantly affected photosynthetic efficiency (Fv/Fm) (p < 0.05) compared to salinity. The maximum quantum yield of corals decreased ranging from 5% to 100% when these corals were exposed to different temperatures and salinities. Temperature also significantly affected coral growth and survival. However, corals exposed to changes in salinity showed higher survivorship than those exposed to changes in temperature. Results in this study also showed that corals of different ages and of different species did not display the same physiological responses to changes in environmental conditions. Thus, the ability of corals to tolerate salinity and temperature stresses depends on several factors.

Functional and genetic characterization of gas exchange and intrinsic water use efficiency in a full-sib family of Pinus pinaster Ait. in response to drought.

PubMed

de Miguel, Marina; Sánchez-Gómez, David; Cervera, María Teresa; Aranda, Ismael

2012-01-01

Drought is an important environmental factor in Mediterranean ecosystems affecting seedling recruitment, productivity or susceptibility to fires and pathogens. Studying water use efficiency in these environments is crucial due to its adaptive value allowing trees to cope with low water availability. We studied the phenotypic variability and genetic control of intrinsic water use efficiency (WUE(i)) and related traits in a full-sib family of Pinus pinaster under drought imposition. We detected significant differences in WUE(i) between clones of the same family and moderate heritability estimates that indicate some degree of genetic control over this trait. Stomatal conductance to water vapor was the trait most affected by drought imposition and it showed the strongest influence in WUE(i). Stomatal conductance to water vapor and specific leaf area (SLA) were the traits with highest heritabilities and they showed a significant genetic correlation with WUE(i), suggesting that selection of needles with low SLA values will improve WUE(i) in this species by reducing water losses through stomatal control.

"You can save time if…"-A qualitative study on internal factors slowing down clinical trials in Sub-Saharan Africa.

PubMed

Vischer, Nerina; Pfeiffer, Constanze; Limacher, Manuela; Burri, Christian

2017-01-01

The costs, complexity, legal requirements and number of amendments associated with clinical trials are rising constantly, which negatively affects the efficient conduct of trials. In Sub-Saharan Africa, this situation is exacerbated by capacity and funding limitations, which further increase the workload of clinical trialists. At the same time, trials are critically important for improving public health in these settings. The aim of this study was to identify the internal factors that slow down clinical trials in Sub-Saharan Africa. Here, factors are limited to those that exclusively relate to clinical trial teams and sponsors. These factors may be influenced independently of external conditions and may significantly increase trial efficiency if addressed by the respective teams. We conducted sixty key informant interviews with clinical trial staff working in different positions in two clinical research centres in Kenya, Ghana, Burkina Faso and Senegal. The study covered English- and French-speaking, and Eastern and Western parts of Sub-Saharan Africa. We performed thematic analysis of the interview transcripts. We found various internal factors associated with slowing down clinical trials; these were summarised into two broad themes, "planning" and "site organisation". These themes were consistently mentioned across positions and countries. "Planning" factors related to budget feasibility, clear project ideas, realistic deadlines, understanding of trial processes, adaptation to the local context and involvement of site staff in planning. "Site organisation" factors covered staff turnover, employment conditions, career paths, workload, delegation and management. We found that internal factors slowing down clinical trials are of high importance to trial staff. Our data suggest that adequate and coherent planning, careful assessment of the setting, clear task allocation and management capacity strengthening may help to overcome the identified internal factors and allow clinical trials to proceed more efficiently.

The Role of Communications, Socio-Psychological, and Personality Factors in the Maintenance of Crew Coordination

NASA Technical Reports Server (NTRS)

Foushee, H. Clayton

1982-01-01

There is increasing evidence that many air transport incidents and accidents are the result of the improper or inadequate utilization of the resources accessible to flight dock crew members. These resources obviously include the hardware and technical information necessary for the safe and efficient conduct of the flight, but they also Include the human resources which must be coordinated effectively. The focus of this paper is upon the human resources, and how communication styles, socio-psychological factors, and personality characteristics can affect crew coordination.

Review of factors affecting recovery of freshwater stored in saline aquifers

USGS Publications Warehouse

Merritt, Michael L.

1989-01-01

A simulation analysis reported previously, and summarized herein, identified the effects of various geohydrologic and operational factors on recoverability of the injected water. Buoyancy stratification, downgradient advection, and hydrodynamic dispersion are the principal natural processes that reduce the amount of injected water that can be recovered. Buoyancy stratification is shown to depend on injection-zone permeability and the density contrast between injected and saline native water. Downgradient advection occurs as a result of natural or induced hydraulic gradients in the aquifer. Hydrodynamic dispersion reduces recovery efficiency by mixing some of the injected water with native saline aquifer water. In computer simulations, the relation of recovery efficiency to volume injected and its improvement during successive injection-recovery cycles was shown to depend on changes in the degree of hydrodynamic dispersion that occurs. Additional aspects of the subject are discussed.

Adsorption of arsenic from aqueous solution using magnetic graphene oxide

NASA Astrophysics Data System (ADS)

Sherlala, A. I. A.; Raman, A. A.; Bello, M. M.

2017-06-01

A binary of graphene oxide (GO) and iron oxide (IO) was prepared and used for the removal of arsenic from aqueous solution. The synthesized compound was characterized using XRD analysis. The prepared composite was used for the adsorption of arsenic from aqueous solution. Central Composite Design was used to design the adsorption experiments and to investigate the effects of operational parameters (initial concentration of arsenic, adsorbent dosage, pH and time) on the adsorption capacity and efficiency. The adsorbent shows a high adsorption capacity for the arsenic. The adsorption efficiency ranges between 33.2 % and 99.95 %. The most significant factors affecting the adsorption capacity were found to be the initial concentration of arsenic and the adsorbent dosage. The initial pH of the solution slightly affects the adsorption capacity, with the maximum adsorption capacity occurring around pH 6 - 7. Thus, the developed adsorbent has a potential for effective removal of arsenic from aqueous solution.

Acute physical exercise affected processing efficiency in an auditory attention task more than processing effectiveness.

PubMed

Dutke, Stephan; Jaitner, Thomas; Berse, Timo; Barenberg, Jonathan

2014-02-01

Research on effects of acute physical exercise on performance in a concurrent cognitive task has generated equivocal evidence. Processing efficiency theory predicts that concurrent physical exercise can increase resource requirements for sustaining cognitive performance even when the level of performance is unaffected. This hypothesis was tested in a dual-task experiment. Sixty young adults worked on a primary auditory attention task and a secondary interval production task while cycling on a bicycle ergometer. Physical load (cycling) and cognitive load of the primary task were manipulated. Neither physical nor cognitive load affected primary task performance, but both factors interacted on secondary task performance. Sustaining primary task performance under increased physical and/or cognitive load increased resource consumption as indicated by decreased secondary task performance. Results demonstrated that physical exercise effects on cognition might be underestimated when only single task performance is the focus.

Enhanced DEA model with undesirable output and interval data for rice growing farmers performance assessment

NASA Astrophysics Data System (ADS)

Khan, Sahubar Ali Mohd. Nadhar; Ramli, Razamin; Baten, M. D. Azizul

2015-12-01

Agricultural production process typically produces two types of outputs which are economic desirable as well as environmentally undesirable outputs (such as greenhouse gas emission, nitrate leaching, effects to human and organisms and water pollution). In efficiency analysis, this undesirable outputs cannot be ignored and need to be included in order to obtain the actual estimation of firms efficiency. Additionally, climatic factors as well as data uncertainty can significantly affect the efficiency analysis. There are a number of approaches that has been proposed in DEA literature to account for undesirable outputs. Many researchers has pointed that directional distance function (DDF) approach is the best as it allows for simultaneous increase in desirable outputs and reduction of undesirable outputs. Additionally, it has been found that interval data approach is the most suitable to account for data uncertainty as it is much simpler to model and need less information regarding its distribution and membership function. In this paper, an enhanced DEA model based on DDF approach that considers undesirable outputs as well as climatic factors and interval data is proposed. This model will be used to determine the efficiency of rice farmers who produces undesirable outputs and operates under uncertainty. It is hoped that the proposed model will provide a better estimate of rice farmers' efficiency.

An Exponential Luminous Efficiency Model for Hypervelocity Impact into Regolith

NASA Technical Reports Server (NTRS)

Swift, Wesley R.; Moser, D.E.; Suggs, Robb M.; Cooke, W.J.

2010-01-01

The flash of thermal radiation produced as part of the impact-crater forming process can be used to determine the energy of the impact if the luminous efficiency is known. From this energy the mass and, ultimately, the mass flux of similar impactors can be deduced. The luminous efficiency, Eta is a unique function of velocity with an extremely large variation in the laboratory range of under 8 km/s but a necessarily small variation with velocity in the meteoric range of 20 to 70 km/s. Impacts into granular or powdery regolith, such as that on the moon, differ from impacts into solid materials in that the energy is deposited via a serial impact process which affects the rate of deposition of internal (thermal) energy. An exponential model of the process is developed which differs from the usual polynomial models of crater formation. The model is valid for the early time portion of the process and focuses on the deposition of internal energy into the regolith. The model is successfully compared with experimental luminous efficiency data from laboratory impacts and from astronomical determinations and scaling factors are estimated. Further work is proposed to clarify the effects of mass and density upon the luminous efficiency scaling factors

Entrapment of ovalbumin into liposomes--factors affecting entrapment efficiency, liposome size, and zeta potential.

PubMed

Brgles, Marija; Jurasin, Darija; Sikirić, Maja Dutour; Frkanec, Ruza; Tomasić, Jelka

2008-01-01

Various amounts of Ovalbumin (OVA) were encapsulated into positively and negatively charged multilamellar liposomes, with the aim to investigate the entrapment efficiency in different buffers and to study their effects on the liposome size and zeta potential. Results showed that the entrapment efficiency of OVA in anionic liposomes was the same in 10 mM Phosphate Buffer (PB) as in Phosphate-Buffered Saline (PBS; PB + 0.15 M NaCl). Also, liposome size was approximately 1200 nm for all anionic liposomes incorporating OVA. The entrapment efficiency of OVA in cationic liposomes was highly dependent on ionic strength. The size of cationic liposomes was approximately 1200 nm in PBS, regardless of protein content, but increased with the amount of the incorporated protein in PB. Aggregation of cationic liposomes in PB was observed when the mass of the protein was 2.5 mg or greater. The zeta potential of anionic liposomes was negative and of cationic liposomes positive in the whole range of protein mass tested. These results show how different compositions of lipid and aqueous phases can be used to vary the entrapment efficiency, liposome size, and zeta potential--the factors that are of great importance for the use of liposomes as drug carriers.

Hermes CX-7: Air transport system design simulation

NASA Technical Reports Server (NTRS)

Amer, Brian; Barter, John; Colucci, Jay; Foley, Caryn; Kockler, James; Rapp, David; Zeiger, Matthew

1992-01-01

The Hermes CX-7 has been designed to service the overnight parcel package delivery needs of the cities of Aeroworld as determined in the G-Dome Enterprises market survey. The design optimization centers on the prime goal of servicing the needs of these cities as efficiently and profitably as possible. The greatest factors which affect the design of an aircraft for the mission outlined in the Request for Proposal are cost, construction feasibility and effectiveness of the design. Other influencing factors are given by the constraints of the market, including a maximum takeoff and landing distance of 60 feet, storage capability in a container of size 5 ft. x 3 ft. x 2 ft., cargo packages of 2 inch and 4 inch cubes, and ability to turn with a radius no larger than 60 feet. Safety considerations such as flying at or below Mach one (30 ft/s) and controllability and maintainability of the aircraft must also be designed into the aircraft. Another influential factor is the efficiency of the aircraft which involves optimizations and tradeoffs of such factors as weight, lifting surface sizing, structural redundancy, and material costs.

A model of memory impairment in schizophrenia: cognitive and clinical factors associated with memory efficiency and memory errors.

PubMed

Brébion, Gildas; Bressan, Rodrigo A; Ohlsen, Ruth I; David, Anthony S

2013-12-01

Memory impairments in patients with schizophrenia have been associated with various cognitive and clinical factors. Hallucinations have been more specifically associated with errors stemming from source monitoring failure. We conducted a broad investigation of verbal memory and visual memory as well as source memory functioning in a sample of patients with schizophrenia. Various memory measures were tallied, and we studied their associations with processing speed, working memory span, and positive, negative, and depressive symptoms. Superficial and deep memory processes were differentially associated with processing speed, working memory span, avolition, depression, and attention disorders. Auditory/verbal and visual hallucinations were differentially associated with specific types of source memory error. We integrated all the results into a revised version of a previously published model of memory functioning in schizophrenia. The model describes the factors that affect memory efficiency, as well as the cognitive underpinnings of hallucinations within the source monitoring framework. © 2013.

Major factors affecting in situ biodegradation rates of jet-fuel during large-scale biosparging project in sedimentary bedrock.

PubMed

Machackova, Jirina; Wittlingerova, Zdena; Vlk, Kvetoslav; Zima, Jaroslav

2012-01-01

Biodegradation of petroleum hydrocarbons (TPH), mainly jet fuel, had taken place at the former Soviet Army air base in the Czech Republic. The remediation of large-scale petroleum contamination of soil and groundwater has provided valuable information about biosparging efficiency in the sandstone sedimentary bedrock. In 1997 petroleum contamination was found to be present in soil and groundwater across an area of 28 hectares, divided for the clean-up purpose into smaller clean-up fields (several hectares). The total estimated quantity of TPH released to the environment was about 7,000 metric tons. Biosparging was applied as an innovative clean-up technology at the site and was operated over a 10-year period (1997-2008). Importance of a variety of factors that affect bacterial activity in unsaturated and saturated zones was widely studied on the site and influence of natural and technological factors on clean-up efficiency in heavily contaminates areas of clean-up fields (initial contaminant mass 111-452 metric ton/ha) was evaluated. Long-term monitoring of the groundwater temperature has shown seasonal rises and falls of temperature which have caused a fluctuation in biodegradation activity during clean-up. By contrast, an overall rise of average groundwater temperature was observed in the clean-up fields, most probably as a result of the biological activity during the clean-up process. The significant rise of biodegradation rates, observed after air sparging intensification, and strong linear correlation between the air injection rates and biodegradation activities have shown that the air injection rate is the principal factor in biodegradation efficiency in heavily contaminated areas. It has a far more important role for achieving a biodegradation activity than the contamination content which appeared to have had only a slight effect after the removal of about 75% of initial contamination.

An Improved Syringe Agroinfiltration Protocol to Enhance Transformation Efficiency by Combinative Use of 5-Azacytidine, Ascorbate Acid and Tween-20.

PubMed

Zhao, Huimin; Tan, Zilong; Wen, Xuejing; Wang, Yucheng

2017-02-14

Syringe infiltration is an important transient transformation method that is widely used in many molecular studies. Owing to the wide use of syringe agroinfiltration, it is important and necessary to improve its transformation efficiency. Here, we studied the factors influencing the transformation efficiency of syringe agroinfiltration. The pCAMBIA1301 was transformed into Nicotiana benthamiana leaves for investigation. The effects of 5-azacytidine (AzaC), Ascorbate acid (ASC) and Tween-20 on transformation were studied. The β-glucuronidase ( GUS ) expression and GUS activity were respectively measured to determine the transformation efficiency. AzaC, ASC and Tween-20 all significantly affected the transformation efficiency of agroinfiltration, and the optimal concentrations of AzaC, ASC and Tween-20 for the transgene expression were identified. Our results showed that 20 μM AzaC, 0.56 mM ASC and 0.03% ( v / v ) Tween-20 is the optimal concentration that could significantly improve the transformation efficiency of agroinfiltration. Furthermore, a combined supplement of 20 μM AzaC, 0.56 mM ASC and 0.03% Tween-20 improves the expression of transgene better than any one factor alone, increasing the transgene expression by more than 6-fold. Thus, an optimized syringe agroinfiltration was developed here, which might be a powerful method in transient transformation analysis.

Compressor blade clearance measurement using capacitance and phase lock techniques

NASA Astrophysics Data System (ADS)

Demers, Rosario N.

1986-11-01

The clearance measurement system has several unique features which mimimize problems plaguing earlier systems. These include tuning stability and sensitivity drift. Both these problems are intensified by the environmental factors present in compressors i.e., wide temperature fluctuations, vibrations, and conductive contamination of probe tips. The circuitry in this new system provides phase lock feedback to control tuning and shut calibration to measure sensitivity. The use of high frequency excitation lowers the probe tip impedance, thus miminizing the effects of contamination. A prototype has been built and tested. The ability to calibrate has been demonstrated. An eight channel system is now being constructed for use in the Compressor Research Facility at Wright-Patterson AFB. The efficiency of a turbine engine is to a large extent dependent upon the mechanical tolerances maintained between its moving parts. On critical tolerance is the blade span. Although this tolerance may not appear severe, the impact on compressor efficiency is dramatic. The penalty in percent efficiency has been shown to be three times the percent clearance to blade span ratio. In addition, each percent loss in compressor efficiency represents one half percent loss in specific fuel consumption. Factors which affect blade tip clearance are identified.

Temporal effects of post-fire check dam construction on soil functionality in SE Spain.

PubMed

González-Romero, J; Lucas-Borja, M E; Plaza-Álvarez, P A; Sagra, J; Moya, D; De Las Heras, J

2018-06-09

Wildfire has historically been an alteration factor in Mediterranean basins. Despite Mediterranean ecosystems' high resilience, wildfire accelerates erosion and degradation processes, and also affects soil functionality by affecting nutrient cycles and soil structure. In semi-arid Mediterranean basins, check dams are usually built in gullies and channels after fire as a measure against soil erosion. Although check dams have proven efficient action to reduce erosion rates, studies about how they affect soil functionality are lacking. Our approach focuses on how soil functionality, defined as a combination of physico-chemical and biological indicators, is locally affected by check dam construction and the evolution of this effect over time. Soils were sampled in eight check dams in two semi-arid areas at SE Spain, which were affected by wildfire in 2012 and 2016. The study findings reveal that by altering sediments cycle and transport, check dams influence soil's main physico-chemical and biochemical characteristics. Significant differences were found between check dam-affected zones and the control ones for many indicators such as organic matter content, electrical conductivity or enzymatic activity. According to the ANOVA results, interaction between check dams influence and time after fire, was a crucial factor. PCA results clearly showed check-dams influence on soil functionality. Copyright © 2018. Published by Elsevier B.V.

Factors of a noninfectious nature affecting fertility after artificial insemination in lactating dairy cows. A review.

PubMed

López-Gatius, F

2012-04-01

After 80 years of the commercial application of artificial insemination (AI) in the cow, the method still has numerous benefits over natural insemination including worldwide gene improvement. The efficiency of insemination depends, among many other factors, on the delivery of an appropriate number of normal spermatozoa to the appropriate reproductive tract site at the appropriate time of estrus. The metabolic clearance of steroid hormones and pregnancy associated glycoproteins and the negative effects of different types of stress related to high milk production makes the high-producing dairy cow a good animal model for addressing factors affecting fertility. Nevertheless, extensive studies have shown a positive link between high milk production in an individual cow and high fertility. When a cow becomes pregnant, the effect of pregnancy loss on its reproductive cycle is also a topic of interest. This paper reviews the factors of a noninfectious nature that affect the fertility of lactating dairy cows following AI. Special attention is paid to factors related to the cow and its environment and to estrus confirmation at insemination. Pregnancy maintenance during the late embryonic/early fetal period is discussed as a critical step. Finally, the use of Doppler ultrasonography is described as an available research tool for improving our current understanding of the health of the genital structures and conceptus. Copyright © 2012 Elsevier Inc. All rights reserved.

Evaluation of Mismatch Losses due to Shunts in industrial Silicon Photovoltaic Modules

NASA Astrophysics Data System (ADS)

Somasundaran, P.; Shilpi, M.; Gupta, R.

2017-05-01

In order to achieve higher efficiencies in photovoltaic module technology, it is important to characterize the shunts and other defects which degrade the performance of cells and modules as well as decrease their efficiency. These shunts also affect the reliability of cells and modules. It is important to understand how much fill factor and power loss is caused by the presence of shunts in the module. Shunts not only reduce the module power output, but also affect the I-V characteristics of the cell and hence the characteristics of the shunted cells are different from those of the shunt-free cells connected in the module leading to the mismatch effect. This is an interesting effect which has been systematically investigated in the present work. Moreover, the flow of increased shunt current will give rise to increased temperature in the region of shunt, which will affect the cell and hence module performance. In the present study, the distributed diode model has been extended to the module level and applied to evaluate the electrical mismatch losses and thermal mismatch losses due to shunts in industrial Silicon PV modules.

Opportunities and constraints for organizations to help sustain tropical forest resources

NASA Astrophysics Data System (ADS)

Hyman, Eric L.

1986-01-01

A large number of organizations make decisions that directly or indirectly affect tropical forests. The principal constraints that affect these organizations are (1) insufficient funds; (2) insufficient knowledge about the resources and appropriate technologies; (3) institutional, cultural, and political factors; (4) inadequate communication; and (5) contradictory efforts. Opportunities for improving the efficiency and effectiveness of these organizations include (1) increasing cooperation among US government agencies; (2) redirecting international organizations; (3) increasing coordination among organizations; (4) boosting support of nongovernmental organizations and universities; (5) encouraging responsible involvement by private corporations; (6) strengthening existing organizations; and (7) creating new organizations.

Gold and Silver Health Plans: Accommodating Demand Heterogeneity in Managed Competition

PubMed Central

Glazer, Jacob; McGuire, Thomas G.

2011-01-01

New regulation of health insurance markets creates multiple levels of health plans, with designations like “Gold” and “Silver”. The underlying rationale for the heavy-metal approach to insurance regulation is that heterogeneity in demand for health care is not only due to health status (sick demand more than the healthy) but also to other, “taste” related factors (rich demand more than the poor). This paper models managed competition with demand heterogeneity to consider plan payment and enrollee premium policies in relation to efficiency (net consumer benefit) and fairness (the European concept of “solidarity”). Specifically, this paper studies how to implement a “Silver” and “Gold” health plan efficiently and fairly in a managed competition context. We show that there are sharp tradeoffs between efficiency and fairness. When health plans cannot or may not (because of regulation) base premiums on any factors affecting demand, enrollees do not choose the efficient plan. When taste (e.g. income) can be used as a basis of payment, a simple tax can achieve both efficiency and fairness. When only health status (and not taste) can be used as a basis of payment, health status-based taxes and subsidies are required and efficiency can only be achieved with a modified version of fairness we refer to as “weak solidarity.” An overriding conclusion is that the regulation of premiums for both the basic and the higher level plans is necessary for efficiency. PMID:21767887

Characterization and optimization of cell seeding in scaffolds by factorial design: quality by design approach for skeletal tissue engineering.

PubMed

Chen, Yantian; Bloemen, Veerle; Impens, Saartje; Moesen, Maarten; Luyten, Frank P; Schrooten, Jan

2011-12-01

Cell seeding into scaffolds plays a crucial role in the development of efficient bone tissue engineering constructs. Hence, it becomes imperative to identify the key factors that quantitatively predict reproducible and efficient seeding protocols. In this study, the optimization of a cell seeding process was investigated using design of experiments (DOE) statistical methods. Five seeding factors (cell type, scaffold type, seeding volume, seeding density, and seeding time) were selected and investigated by means of two response parameters, critically related to the cell seeding process: cell seeding efficiency (CSE) and cell-specific viability (CSV). In addition, cell spatial distribution (CSD) was analyzed by Live/Dead staining assays. Analysis identified a number of statistically significant main factor effects and interactions. Among the five seeding factors, only seeding volume and seeding time significantly affected CSE and CSV. Also, cell and scaffold type were involved in the interactions with other seeding factors. Within the investigated ranges, optimal conditions in terms of CSV and CSD were obtained when seeding cells in a regular scaffold with an excess of medium. The results of this case study contribute to a better understanding and definition of optimal process parameters for cell seeding. A DOE strategy can identify and optimize critical process variables to reduce the variability and assists in determining which variables should be carefully controlled during good manufacturing practice production to enable a clinically relevant implant.

Identifying the influential aquifer heterogeneity factor on nitrate reduction processes by numerical simulation

NASA Astrophysics Data System (ADS)

Jang, E.; He, W.; Savoy, H.; Dietrich, P.; Kolditz, O.; Rubin, Y.; Schüth, C.; Kalbacher, T.

2017-01-01

Nitrate reduction reactions in groundwater systems are strongly influenced by various aquifer heterogeneity factors that affect the transport of chemical species, spatial distribution of redox reactive substances and, as a result, the overall nitrate reduction efficiency. In this study, we investigated the influence of physical and chemical aquifer heterogeneity, with a focus on nitrate transport and redox transformation processes. A numerical modeling study for simulating coupled hydrological-geochemical aquifer heterogeneity was conducted in order to improve our understanding of the influence of the aquifer heterogeneity on the nitrate reduction reactions and to identify the most influential aquifer heterogeneity factors throughout the simulation. Results show that the most influential aquifer heterogeneity factors could change over time. With abundant presence of electron donors in the high permeable zones (initial stage), physical aquifer heterogeneity significantly influences the nitrate reduction since it enables the preferential transport of nitrate to these zones and enhances mixing of reactive partners. Chemical aquifer heterogeneity plays a comparatively minor role. Increasing the spatial variability of the hydraulic conductivity also increases the nitrate removal efficiency of the system. However, ignoring chemical aquifer heterogeneity can lead to an underestimation of nitrate removals in long-term behavior. With the increase of the spatial variability of the electron donor, i.e. chemical heterogeneity, the number of the ;hot spots; i.e. zones with comparably higher reactivity, should also increase. Hence, nitrate removal efficiencies will also be spatially variable but overall removal efficiency will be sustained if longer time scales are considered and nitrate fronts reach these high reactivity zones.

Development of Solar Grade Silicon (SoG-Si) Feedstock by Recycling SoG-Si Wastes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lifeng Zhang; Anping Dong; Lucas Nana Wiredu Damoah

2013-01-24

Experiment results of EM separation show that the non-metallic inclusions were successfully pushed to the boundary layer of the crucible under EM force. Larger frequency and smaller current generate smaller thickness of accumulated inclusions. More detailed EM separation experiments are undergoing to investigate the factors that affect the removal efficient of inclusions from SoG-Si

Parent Inclusion in Early Intensive Behavioral Intervention: The Influence of Parental Stress, Parent Treatment Fidelity and Parent-Mediated Generalization of Behavior Targets on Child Outcomes

ERIC Educational Resources Information Center

Strauss, Kristin; Vicari, Stefano; Valeri, Giovanni; D'Elia, Lidia; Arima, Serena; Fava, Leonardo

2012-01-01

Although early intensive behavior interventions have been efficient in producing positive behavior outcome in young children with Autism Spectrum Disorder, there is a considerable variety in the children's progress. Research has suggested that parental and treatment factors are likely to affect children's response to treatment. The purpose of the…

Factors that affect fuel consumption in logging systems

Treesearch

Jonathan Kenney; Thomas Gallagher; Matthew Smidt; Dana Mitchell; Timothy and McDonald

2014-01-01

Fuel consumption is an important aspect of the efficiency of timber harvesting. Since loggers are paid based on the weight of wood they produce, it is important to note how many gallons of fuel it takes to produce one ton of wood. An extensive literature review was conducted to evaluate different harvesting systems and the amount of fuel they consumed per unit of wood...

Factors affecting performance and productivity of nurses: professional attitude, organisational justice, organisational culture and mobbing.

PubMed

Terzioglu, Fusun; Temel, Safiye; Uslu Sahan, Fatma

2016-09-01

To identify relationships among variables affecting nurses' performance and productivity, namely professional attitudes, organisational culture, organisational justice and exposure to mobbing. The determination of the factors affecting performance and productivity is important for providing efficient nursing services. These factors have been investigated in the literature independently, but the relationship among them has not been clearly identified. This cross-sectional questionnaire study included 772 nurses working in a University Hospital accredited by Joint Commission International. The professional attitude score of the nurses was high (4.35 ± 0.63). However, their organisational justice (2.22 ± 1.26) and organisational culture (2.47 ± 0.71) scores were low. Nurses were subjected to mobbing at a high level (0.82 ± 0.78). As the organisational justice increased, the organisational culture increased and the mobbing decreased. As the organisation culture decreased, the mobbing increased. There was a positive correlation between organisation culture and organisational justice of the nurses and a negative correlation with mobbing. The results of the study are essential for improving nurses' performance and productivity. © 2016 John Wiley & Sons Ltd.

An ERP study of conflict monitoring in 4-8-year old children: associations with temperament.

PubMed

Buss, Kristin A; Dennis, Tracy A; Brooker, Rebecca J; Sippel, Lauren M

2011-04-01

Although there is great interest in identifying the neural correlates of cognitive processes that create risk for psychopathology, there is a paucity of research in young children. One event-related potential (ERP), the N2, is thought to index conflict monitoring and has been linked cognitive and affective risk factors for anxiety. Most of this research, however, has been conducted with adults, adolescents, and older children, but not with younger children. To address this gap, the current study examined 26 4-8-year-olds, who completed a cued flanker task while EEG was continuously recorded. We assessed whether the N2 was detectable in this group of young children and examined associations between the N2 and factors reflecting affective risk (e.g., reduced executive attention, temperamental effortful control, and temperamental surgency). We documented an N2 effect (greater N2 amplitude to incongruent versus congruent flankers), but only in children older than 6 years of age. Increases in the N2 effect were associated with less efficient executive attention and lower temperamental effortful control. We discuss the implications of these findings and consider how they may inform future studies on biomarkers for cognitive and affective risk factors for anxiety.

Restorative Rehabilitation of a Patient with Dental Erosion

PubMed Central

AlShahrani, Mohammed Thamer; Alqarni, Mohammed

2017-01-01

Dental erosion is the chemical dissolution of the tooth structure. Factors like eating disorders and gastrointestinal diseases are recognized as intrinsic factors for dental erosion. Advanced stages of dental erosion extensively damage the tooth morphology, consequently affecting both esthetics and functions. Reports indicate the growing prevalence of erosion, and hence knowledge of restorative rehabilitation of tooth erosion is an integral part of the contemporary dental practice. This clinical report describes an adult patient with gastroesophageal reflux induced dental erosion involving the palatal surface of the maxillary anterior teeth. The extensive involvement of the palatal surfaces compromised the esthetics, incisal guidance, and functional occlusal efficiency. Indirect all-ceramic restorations were utilized to restore the esthetics and occlusal reconstruction. In conclusion, patients affected by severe dental erosion require prosthetic rehabilitation besides the management of the associated medical condition. PMID:28828189

Restorative Rehabilitation of a Patient with Dental Erosion.

PubMed

AlShahrani, Mohammed Thamer; Haralur, Satheesh B; Alqarni, Mohammed

2017-01-01

Dental erosion is the chemical dissolution of the tooth structure. Factors like eating disorders and gastrointestinal diseases are recognized as intrinsic factors for dental erosion. Advanced stages of dental erosion extensively damage the tooth morphology, consequently affecting both esthetics and functions. Reports indicate the growing prevalence of erosion, and hence knowledge of restorative rehabilitation of tooth erosion is an integral part of the contemporary dental practice. This clinical report describes an adult patient with gastroesophageal reflux induced dental erosion involving the palatal surface of the maxillary anterior teeth. The extensive involvement of the palatal surfaces compromised the esthetics, incisal guidance, and functional occlusal efficiency. Indirect all-ceramic restorations were utilized to restore the esthetics and occlusal reconstruction. In conclusion, patients affected by severe dental erosion require prosthetic rehabilitation besides the management of the associated medical condition.

On the efficiency of the golf swing

NASA Astrophysics Data System (ADS)

White, Rod

2006-12-01

A non-driven double pendulum model is used to explain the principle underlying the surprising efficiency of the golf swing. The principle can be described as a parametric energy transfer between the arms and the club head due to the changing moment of inertia of the club. The transfer is a consequence of conservation of energy and angular momentum. Because the pendulum is not driven by an external force, it shows that the golfer need do little more than accelerate the arms with the wrists cocked and let the double pendulum transfer kinetic energy to the club head. A driven double pendulum model is used to study factors affecting the efficiency of a real golf swing. It is concluded that the wrist-cock angle is the most significant efficiency-determining parameter under the golfer's control and that improvements in golf technology have had a significant impact on driving distance.

Estimation and modeling of electrofishing capture efficiency for fishes in wadeable warmwater streams

USGS Publications Warehouse

Price, A.; Peterson, James T.

2010-01-01

Stream fish managers often use fish sample data to inform management decisions affecting fish populations. Fish sample data, however, can be biased by the same factors affecting fish populations. To minimize the effect of sample biases on decision making, biologists need information on the effectiveness of fish sampling methods. We evaluated single-pass backpack electrofishing and seining combined with electrofishing by following a dual-gear, mark–recapture approach in 61 blocknetted sample units within first- to third-order streams. We also estimated fish movement out of unblocked units during sampling. Capture efficiency and fish abundances were modeled for 50 fish species by use of conditional multinomial capture–recapture models. The best-approximating models indicated that capture efficiencies were generally low and differed among species groups based on family or genus. Efficiencies of single-pass electrofishing and seining combined with electrofishing were greatest for Catostomidae and lowest for Ictaluridae. Fish body length and stream habitat characteristics (mean cross-sectional area, wood density, mean current velocity, and turbidity) also were related to capture efficiency of both methods, but the effects differed among species groups. We estimated that, on average, 23% of fish left the unblocked sample units, but net movement varied among species. Our results suggest that (1) common warmwater stream fish sampling methods have low capture efficiency and (2) failure to adjust for incomplete capture may bias estimates of fish abundance. We suggest that managers minimize bias from incomplete capture by adjusting data for site- and species-specific capture efficiency and by choosing sampling gear that provide estimates with minimal bias and variance. Furthermore, if block nets are not used, we recommend that managers adjust the data based on unconditional capture efficiency.

Diffraction Efficiency of Thin Film Holographic Beam Steering Devices

NASA Technical Reports Server (NTRS)

Titus, Charles M.; Pouch, John; Nguyen, Hung; Miranda, Felix; Bos, Philip J.

2003-01-01

Dynamic holography has been demonstrated as a method for correcting aberrations in space deployable optics, and can also be used to achieve high-resolution beam steering in the same environment. In this paper, we consider some of the factors affecting the efficiency of these devices. Specifically, the effect on the efficiency of a highly collimated beam from the number of discrete phase steps per period is considered for a blazed thin film beam steering grating. The effect of the number of discrete phase steps per period on steering resolution is also considered. We also present some result of Finite-Difference Time-Domain (FDTD) calculations of light propagating through liquid crystal "blazed" gratings. Liquid crystal gratings are shown to spatially modulate both the phase and amplitude of the propagating light.

We have just begun to create efficient transport aircraft

NASA Technical Reports Server (NTRS)

Maglieri, D. J.; Dollyhigh, S. M.

1982-01-01

Factors affecting the cost-effectiveness and economics of the air transportation industry are reviewed. The delivery of more fuel-efficient aircraft and eventual total replacement in the 1990's by fleets of advanced aircraft are seen to offset rising fuel costs. Better airport operations are perceived to eliminate fuel-costly delays due to overcrowded runways, lack of available carriers, and maintenance of aircraft in holding patterns. Noise reduction research will lower the lawsuit costs from noise pollution, and the introduction of advanced turbofans for long, short, and medium range flights, advanced commuter planes, and advanced SSTs offering projected 50% increases in current aircraft efficiencies are seen to be limited only by the airlines' ability to provide purchase financing, rather than by a lack of available new technology.

Optimization of Artificial Propagation in Piracanjuba Fish Brycon orbignyanus Using Cryopreserved Semen.

PubMed

Felizardo, V O; Melo, C C V; Murgas, L D S; Andrade, E S; Navarro, R D; Ftreitas, T F

BACKGROUND: Cryopreserved semen could facilitate procedures during the artificial reproduction in fish. Factors affecting cryopreservation efficiency are important to define efficient protocols. This study investigated the application of cryoprotectants on the quality of piracanjuba fish semen, the sperm concentration required for oocyte fertilization and spermatic activation. We evaluated two intracellular cryoprotectant solutions (DMSO and methanol) and two extracellular cryoprotectant solutions (egg yolk and lactose) to cryopreserved piracanjuba semen. Sperm motility rate, motility duration and spermatic alterations were assessed. The protocol for piracanjuba semen cryopreservation can use solutions including either DMSO or methanol as intracellular cryoprotectant and egg yolk or lactose as extracellular cryoprotectants.

Spatial Characteristics and Driving Factors of Provincial Wastewater Discharge in China.

PubMed

Chen, Kunlun; Liu, Xiaoqiong; Ding, Lei; Huang, Gengzhi; Li, Zhigang

2016-12-09

Based on the increasing pressure on the water environment, this study aims to clarify the overall status of wastewater discharge in China, including the spatio-temporal distribution characteristics of wastewater discharge and its driving factors, so as to provide reference for developing "emission reduction" strategies in China and discuss regional sustainable development and resources environment policies. We utilized the Exploratory Spatial Data Analysis (ESDA) method to analyze the characteristics of the spatio-temporal distribution of the total wastewater discharge among 31 provinces in China from 2002 to 2013. Then, we discussed about the driving factors, affected the wastewater discharge through the Logarithmic Mean Divisia Index (LMDI) method and classified those driving factors. Results indicate that: (1) the total wastewater discharge steadily increased, based on the social economic development, with an average growth rate of 5.3% per year; the domestic wastewater discharge is the main source of total wastewater discharge, and the amount of domestic wastewater discharge is larger than the industrial wastewater discharge. There are many spatial differences of wastewater discharge among provinces via the ESDA method. For example, provinces with high wastewater discharge are mainly the developed coastal provinces such as Jiangsu Province and Guangdong Province. Provinces and their surrounding areas with low wastewater discharge are mainly the undeveloped ones in Northwest China; (2) The dominant factors affecting wastewater discharge are the economy and technological advance; The secondary one is the efficiency of resource utilization, which brings about the unstable effect; population plays a less important role in wastewater discharge. The dominant driving factors affecting wastewater discharge among 31 provinces are divided into three types, including two-factor dominant type, three-factor leading type and four-factor antagonistic type. In addition, the proposals aimed at reducing the wastewater discharge are provided on the basis of these three types.

Factors affecting physicians' responses to patients' requests for antidepressants: focus group study.

PubMed

Tentler, Aleksey; Silberman, Jordan; Paterniti, Debora A; Kravitz, Richard L; Epstein, Ronald M

2008-01-01

The ways in which patients' requests for antidepressants affect physicians' prescribing behavior are poorly understood. To describe physicians' affective and cognitive responses to standardized patients' (SPs) requests for antidepressants, as well as the attitudinal and contextual factors influencing prescribing behavior. Focus group interviews and brief demographic questionnaires. Twenty-two primary care physicians in 6 focus groups; all had participated in a prior RCT of the influence of patients' requests on physicians' prescribing. Iterative review of interview transcripts, involving qualitative coding and thematic analysis. Physicians participating in the focus groups were frequently unaware of and denied the degree to which their thinking was biased by patient requests, but were able to recognize such biases after facilitated reflection. Common affective responses included annoyance and empathy. Common cognitive reactions resulted in further diagnostic inquiry or in acquiescing to the patient's demands to save time or build the patient-clinician relationship. Patients' requests for medication prompted the participants to err on the side of overtreating versus careful review of clinical indications. Lack of time and participants' attitudes--toward the role of the patient and the pharmaceutical ads--also influenced their responses, prompting them to interpret patient requests as diagnostic clues or opportunities for efficiency. This study provides a taxonomy of affective and cognitive responses to patients' requests for medications and the underlying attitudes and contextual factors influencing them. Improved capacity for moment-to-moment self-awareness during clinical reasoning processes may increase the appropriateness of prescribing.

The effect of environmental pH on polymeric transfection efficiency.

PubMed

Kang, Han Chang; Samsonova, Olga; Kang, Sun-Woong; Bae, You Han

2012-02-01

Although polymers, polyplexes, and cells are exposed to various extracellular and intracellular pH environments during polyplex preparation and polymeric transfection, the impact of environmental pH on polymeric transfection has not yet been investigated. This study aims to understand the influence of environmental pH on polymeric transfection by modulating the pH of the transfection medium or the culture medium. Changes in the extracellular pH affected polymeric transfection by way of complex factors such as pH-induced changes in polymer characteristics (e.g., proton buffering capacity and ionization), polyplex characteristics (e.g., size, surface charge, and decomplexation), and cellular characteristics (e.g., cellular uptake, cell cycle phases, and intracellular pH environment). Notably, acidic medium delayed endocytosis, endosomal acidification, cytosolic release, and decomplexation of polyplexes, thereby negatively affecting gene expression. However, acidic medium inhibited mitosis and reduced dilution of gene expression, resulting in increased transfection efficiency. Compared to pH 7.4 medium, acidic transfection medium reduced gene expression 1.6-7.7-fold whereas acidic culture medium enhanced transfection efficiency 2.1-2.6-fold. Polymeric transfection was affected more by the culture medium than by the transfection medium. Understanding the effects of extracellular pH during polymeric transfection may stimulate new strategies for determining effective and safe polymeric gene carriers. Copyright © 2011 Elsevier Ltd. All rights reserved.

Considerations for higher efficiency and productivity in research activities.

PubMed

Forero, Diego A; Moore, Jason H

2016-01-01

There are several factors that are known to affect research productivity; some of them imply the need for large financial investments and others are related to work styles. There are some articles that provide suggestions for early career scientists (PhD students and postdocs) but few publications are oriented to professors about scientific leadership. As academic mentoring might be useful at all levels of experience, in this note we suggest several key considerations for higher efficiency and productivity in academic and research activities. More research is needed into the main work style features that differentiate highly productive scientists and research groups, as some of them could be innate and others could be transferable. As funding agencies, universities and research centers invest large amounts of money in order to have a better scientific productivity, a deeper understanding of these factors will be of high academic and societal impact.

Arabidopsis BPM proteins function as substrate adaptors to a cullin3-based E3 ligase to affect fatty acid metabolism in plants.

PubMed

Chen, Liyuan; Lee, Joo Hyun; Weber, Henriette; Tohge, Takayuki; Witt, Sandra; Roje, Sanja; Fernie, Alisdair R; Hellmann, Hanjo

2013-06-01

Regulation of transcriptional processes is a critical mechanism that enables efficient coordination of the synthesis of required proteins in response to environmental and cellular changes. Transcription factors require accurate activity regulation because they play a critical role as key mediators assuring specific expression of target genes. In this work, we show that cullin3-based E3 ligases have the potential to interact with a broad range of ethylene response factor (ERF)/APETALA2 (AP2) transcription factors, mediated by Math-BTB/POZ (for Meprin and TRAF [tumor necrosis factor receptor associated factor] homolog)-Broad complex, Tramtrack, Bric-a-brac/Pox virus and Zinc finger) proteins. The assembly with an E3 ligase causes degradation of their substrates via the 26S proteasome, as demonstrated for the wrinkled1 ERF/AP2 protein. Furthermore, loss of Math-BTB/POZ proteins widely affects plant development and causes altered fatty acid contents in mutant seeds. Overall, this work demonstrates a link between fatty acid metabolism and E3 ligase activities in plants and establishes CUL3-based E3 ligases as key regulators in transcriptional processes that involve ERF/AP2 family members.

Cost and efficiency of disaster waste disposal: A case study of the Great East Japan Earthquake.

PubMed

Sasao, Toshiaki

2016-12-01

This paper analyzes the cost and efficiency of waste disposal associated with the Great East Japan Earthquake. The following two analyses were performed: (1) a popular parametric approach, which is an ordinary least squares (OLS) method to estimate the factors that affect the disposal costs; (2) a non-parametric approach, which is a two-stage data envelopment analysis (DEA) to analyze the efficiency of each municipality and clarify the best performance of the disaster waste management. Our results indicate that a higher recycling rate of disaster waste and a larger amount of tsunami sediments decrease the average disposal costs. Our results also indicate that area-wide management increases the average cost. In addition, the efficiency scores were observed to vary widely by municipality, and more temporary incinerators and secondary waste stocks improve the efficiency scores. However, it is likely that the radioactive contamination from the Fukushima Daiichi nuclear power station influenced the results. Copyright © 2016 Elsevier Ltd. All rights reserved.

How Redundant Are Redundant Color Adjectives? An Efficiency-Based Analysis of Color Overspecification

PubMed Central

Rubio-Fernández, Paula

2016-01-01

Color adjectives tend to be used redundantly in referential communication. I propose that redundant color adjectives (RCAs) are often intended to exploit a color contrast in the visual context and hence facilitate object identification, despite not being necessary to establish unique reference. Two language-production experiments investigated two types of factors that may affect the use of RCAs: factors related to the efficiency of color in the visual context and factors related to the semantic category of the noun. The results of Experiment 1 confirmed that people produce RCAs when color may facilitate object recognition; e.g., they do so more often in polychrome displays than in monochrome displays, and more often in English (pre-nominal position) than in Spanish (post-nominal position). RCAs are also used when color is a central property of the object category; e.g., people referred to the color of clothes more often than to the color of geometrical figures (Experiment 1), and they overspecified atypical colors more often than variable and stereotypical colors (Experiment 2). These results are relevant for pragmatic models of referential communication based on Gricean pragmatics and informativeness. An alternative analysis is proposed, which focuses on the efficiency and pertinence of color in a given referential situation. PMID:26924999

Predicting a roadkill hotspots based on spatial distribution of Korean water deer (Hydropotes inermis argyropus) using Maxent model in South Korea Expressway : In Case of Cheongju-Sangju Expressway

NASA Astrophysics Data System (ADS)

Park, Hyomin; Lee, Sangdon

2016-04-01

Road construction has direct and indirect effects on ecosystems. Especially wildlife-vehicle conflicts (roadkills) caused by roads are a considerable threat for population of many species. This study aims to identify the effects of topographic characteristics and spatial distribution of Korean water deer (Hydropotes inermis). Korean water deer is indigenous and native species in Korea that listed LC (least concern) by IUCN redlist categories. Korean water deer population is growing every year occupying for most of roadkills (>70%) in Korean express highway. In order to predict a distribution of the Korean water deer, we selected factors that most affected water deer's habitat. Major habitats of waterdeer are known as agricultural area, forest area and water. Based on this result, eight factors were selected (land cover map, vegetation map, age class of forest, diameter class of tree, population, slope of study site, elevation of study site, distance of river), and made a thematic map by using GIS program (ESRI, Arc GIS 10.3.1 ver.). To analyze the affected factors of waterdeer distribution, GPS data and thematic map of study area were entered into Maxent model (Maxent 3.3.3.k.). Results of analysis were verified by the AUC (Area Unit Curve) of ROC (Receiver Operating Characteristic). The ROC curve used the sensitivity and specificity as a reference for determining the prediction efficiency of the model and AUC area of ROC curve was higher prediction efficiency closer to '1.' Selecting factors that affected the distribution of waterdeer were land cover map, diameter class of tree and elevation of study site. The value of AUC was 0.623. To predict the water deer's roadkills hot spot on Cheongju-Sangju Expressway, the thematic map was prepared based on GPS data of roadkill spots. As a result, the topographic factors that affected waterdeer roadkill were land cover map, actual vegetation map and age class of forest and the value of AUC was 0.854. Through this study, we could identify the site and hot spots that water deer frequently expected to use based on quantitative data on the spatial and topographic factors. Therefore, we can suggest ways to minimize roadkills by selecting the hot spots and by suggesting construction of eco-corridors. This study will significantly enhance human-wildlife conflicts by identifying key habitat areas for wild mammals.

Affective temperament and executive functions in emergency medicine professionals.

PubMed

Jaracz, Marcin; Paciorek, Przemysław; Buciński, Adam; Borkowska, Alina

2014-10-01

Recent studies indicate that choice of profession is related to differences in affective temperament, which is probably due to various predispositions needed to efficiently perform particular professions. The aim of the present study was to assess affective temperament and executive functions in a sample of emergency medicine professionals. 75 emergency medicine professionals were enrolled in the study. Affective temperament was assessed by means of TEMPS-A. Executive functions were assessed by means of Trail Making Test and Stroop Color Word Interference Test. Subjects showed significantly higher rates of hyperthymic, compared to depressive, cyclothymic, irritable and anxious temperaments. The principal component analysis revealed that hyperthymic temperament contributes to a different factor, than the remaining ones. Higher rates of depressive, cyclothymic, irritable and anxious temperaments were related to poorer performance in Trail Making Test, whereas hyperthymic temperament had the opposite effect. Due to the size of the sample, results of the present study may have lacked power to show all the relationships between tested variables. Hyperthymic temperament promotes efficient performance of complex tasks under time pressure. Depressive, cyclothymic, irritable and anxious temperaments have the opposite effect. This makes hyperthymic temperament a desirable trait in emergency medicine professionals, performing complex medical tasks under extreme conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

Review of capital investment in economic growth cycle

NASA Astrophysics Data System (ADS)

Shaffie, Siti Salihah; Jaaman, Saiful Hafizah; Mohamad, Daud

2016-11-01

The study of linkages of macroeconomics factors is prominent in order to understand how the economic cycle affects one another. These factors include interest rate, growth rate, saving and capital investment which are mutually correlated to stabilize the GDP. Part of this study, it will look upon the impact of investment which emphasize the efficiency of capital investment to the economic growth. Capital investment is one investment appraisal that gives impact to the economic growth. It is a long term investment and involve with large amount of capital to incorporate the development of private and public capital investment.

Review of factors affecting aircraft wet runway performance

NASA Technical Reports Server (NTRS)

Yager, T. J.

1983-01-01

Problems associated with aircraft operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research results from investigations conducted at the Langley Aircraft Landing Loads and Traction Facility and from tests with instrumented ground vehicles and aircraft are summarized to indicate the effects of different aircraft, tire, and runway parameters. Several promising means are described for improving tire/runway water drainage capability, brake system efficiency, and pilot training to help optimize aircraft traction performance on wet runways.

Preliminary assessment of injection, storage, and recovery of freshwater in the lower Hawthorn aquifer, Cape Coral, Florida

USGS Publications Warehouse

Quinones-Aponte, Vicente; Wexler, Eliezer J.

1995-01-01

A preliminary assessment of subsurface injection, storage and recovery of fresh canal water was made in the naturally brackish lower Hawthorn aquifer in Cape Coral, southwestern Florida. A digital modeling approach was used for this preliminary assessment, incorporating available data on hydrologic conditions, aquifer properties, and water quality to simulate density-dependent ground-water flow and advective-dispersive transport of a conservative ground-water solute (chloride ion). A baseline simulation was used as reference to compare the effects of changing various operational factors on the recovery efficiency. A recovery efficiency of 64 percent was estimated for the baseline simulation. Based on the model, the recovery efficiency increases if the injection rate and recovery rates are increased and if the ratio of recovery rate to injection rate is increased. Recovery efficiency decreases if the amount of water injected is increased; slightly decreases if the storage time is increased; is not changed significantly if the water is injected to a specific flow zone; increases with successive cycles of injection, storage, and recovery; and decreases if the chloride concentrations in either the injection water or native aquifer water are increased. In everal hypothetical tests, the recovery efficiency fluctuated between 22 and about 100 percent. Two successive cycles could bring the recovery efficiency from 60 to about 80 percent. Interlayer solute mass movement across the upper and lower boundaries seems to be the most important factor affecting the recovery efficiency. A sensitivity analysis was performed applying a technique in which the change in the various factors and the corresponding model responses are normalized so that meaningful comparisons among the responses could be made. The general results from the sensitivity analysis indicated that the permeabilities of the upper and lower flow zones were the most important factors that produced the greatest changes in the relative sensitivity of the recovery efficiency. Almost equally significant changes occurred in the relative sensitivity of the recovery efficiency when all porosity values of the upper and lower flow zones and the leaky confining units and the vertical anisotropy ratio were changed. The advective factors are the most important in the Cape Coral area according to the sensitivity analysis. However, the dispersivity values used in the model were extrapolated from studies conducted at the nearby Lee County Water Treatment Plant, and these values might not be representative of the actual dispersive characteristics of the lower Hawthorn aquifer in the Cape Coral area.

Mathematical model of design loading vessel

NASA Astrophysics Data System (ADS)

Budnik, V. Yu

2017-10-01

Transport by ferry is very important in our time. The paper shows the factors that affect the operation of the ferry. The constraints of the designed system were identified. The indicators of quality were articulated. It can be done by means of improving the decision-making process and the choice of the optimum loading options to ensure efficient functioning of Kerch strait ferry line. The algorithm and a mathematical model were developed.

Description and expected performance of flight-model, 12-gigahertz, output stage tube for the communications technology satellite

NASA Technical Reports Server (NTRS)

Chomos, G. J.; Curren, A. N.

1976-01-01

The flight model output stage tube for the Communications Technology Satellite is described. The output stage tube is a 12-GHz, 200-W, coupled cavity traveling wave tube. The tube has a multistage depressed collector for efficiency enhancement. Collector cooling is accomplished by direct radiation to space. Expected rf performance and factors affecting on orbit performance and life are discussed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Padaki, S.; Drzal, L.T.

The consolidation process in composites made out of powder impregnated tapes differs from that of other material forms because of the distribution of fiber and matrix in the unconsolidated state. A number of factors (e.g. time, pressure, particle size, volume fraction and viscosity) affect the efficiency of the consolidation of these tapes. This paper describes the development of a mathematical process model that describes the best set of parameters required for the consolidation of a given prepreg tape.

Effects of MERV 16 filters and routine work practices on enclosed cabs for reducing respirable dust and DPM exposures in an underground limestone mine

PubMed Central

Noll, J.D.; Cecala, A.B.; J.A.Organiscak; Rider, J.P.

2015-01-01

An effective technique to minimize miners’ respirable dust and diesel exposure on mobile mining equipment is to place mine operators in enclosed cabs with designed filtration and pressurization systems. Many factors affect the performance of these enclosed cab systems, and one of the most significant factors is the effectiveness of the filtration system. High-efficiency particulate air (HEPA)-type filters are typically used because they are highly efficient at capturing all types and sizes of particles, including those in the submicron range such as diesel particulate matter (DPM). However, in laboratory tests, minimum efficiency reporting value (MERV) 16 filters have proven to be highly efficient for capturing DPM and respirable dust. Also, MERV 16 filters can be less restrictive to cab airflow and less expensive than HEPA filters. To verify their effectiveness in the field, MERV 16 filters were used in the enclosed cab filtration system on a face drill and roof bolting mining machine and tested at an underground limestone mine. Test results showed that DPM and respirable dust concentrations were reduced by more than 90% when the cabs were properly sealed. However, when the cab door was opened periodically throughout the shift, the reduction efficiency of the MERV 16 filters was reduced to 80% on average. PMID:26236044

Enhanced DEA model with undesirable output and interval data for rice growing farmers performance assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khan, Sahubar Ali Mohd. Nadhar, E-mail: sahubar@uum.edu.my; Ramli, Razamin, E-mail: razamin@uum.edu.my; Baten, M. D. Azizul, E-mail: baten-math@yahoo.com

Agricultural production process typically produces two types of outputs which are economic desirable as well as environmentally undesirable outputs (such as greenhouse gas emission, nitrate leaching, effects to human and organisms and water pollution). In efficiency analysis, this undesirable outputs cannot be ignored and need to be included in order to obtain the actual estimation of firms efficiency. Additionally, climatic factors as well as data uncertainty can significantly affect the efficiency analysis. There are a number of approaches that has been proposed in DEA literature to account for undesirable outputs. Many researchers has pointed that directional distance function (DDF) approachmore » is the best as it allows for simultaneous increase in desirable outputs and reduction of undesirable outputs. Additionally, it has been found that interval data approach is the most suitable to account for data uncertainty as it is much simpler to model and need less information regarding its distribution and membership function. In this paper, an enhanced DEA model based on DDF approach that considers undesirable outputs as well as climatic factors and interval data is proposed. This model will be used to determine the efficiency of rice farmers who produces undesirable outputs and operates under uncertainty. It is hoped that the proposed model will provide a better estimate of rice farmers’ efficiency.« less

Comparative analysis of quantitative efficiency evaluation methods for transportation networks

PubMed Central

He, Yuxin; Hong, Jian

2017-01-01

An effective evaluation of transportation network efficiency could offer guidance for the optimal control of urban traffic. Based on the introduction and related mathematical analysis of three quantitative evaluation methods for transportation network efficiency, this paper compares the information measured by them, including network structure, traffic demand, travel choice behavior and other factors which affect network efficiency. Accordingly, the applicability of various evaluation methods is discussed. Through analyzing different transportation network examples it is obtained that Q-H method could reflect the influence of network structure, traffic demand and user route choice behavior on transportation network efficiency well. In addition, the transportation network efficiency measured by this method and Braess’s Paradox can be explained with each other, which indicates a better evaluation of the real operation condition of transportation network. Through the analysis of the network efficiency calculated by Q-H method, it can also be drawn that a specific appropriate demand is existed to a given transportation network. Meanwhile, under the fixed demand, both the critical network structure that guarantees the stability and the basic operation of the network and a specific network structure contributing to the largest value of the transportation network efficiency can be identified. PMID:28399165

Comparative analysis of quantitative efficiency evaluation methods for transportation networks.

PubMed

He, Yuxin; Qin, Jin; Hong, Jian

2017-01-01

An effective evaluation of transportation network efficiency could offer guidance for the optimal control of urban traffic. Based on the introduction and related mathematical analysis of three quantitative evaluation methods for transportation network efficiency, this paper compares the information measured by them, including network structure, traffic demand, travel choice behavior and other factors which affect network efficiency. Accordingly, the applicability of various evaluation methods is discussed. Through analyzing different transportation network examples it is obtained that Q-H method could reflect the influence of network structure, traffic demand and user route choice behavior on transportation network efficiency well. In addition, the transportation network efficiency measured by this method and Braess's Paradox can be explained with each other, which indicates a better evaluation of the real operation condition of transportation network. Through the analysis of the network efficiency calculated by Q-H method, it can also be drawn that a specific appropriate demand is existed to a given transportation network. Meanwhile, under the fixed demand, both the critical network structure that guarantees the stability and the basic operation of the network and a specific network structure contributing to the largest value of the transportation network efficiency can be identified.

Factors affecting study efficiency and item non-response in health surveys in developing countries: the Jamaica national healthy lifestyle survey.

PubMed

Wilks, Rainford; Younger, Novie; Mullings, Jasneth; Zohoori, Namvar; Figueroa, Peter; Tulloch-Reid, Marshall; Ferguson, Trevor; Walters, Christine; Bennett, Franklyn; Forrester, Terrence; Ward, Elizabeth; Ashley, Deanna

2007-02-28

Health surveys provide important information on the burden and secular trends of risk factors and disease. Several factors including survey and item non-response can affect data quality. There are few reports on efficiency, validity and the impact of item non-response, from developing countries. This report examines factors associated with item non-response and study efficiency in a national health survey in a developing Caribbean island. A national sample of participants aged 15-74 years was selected in a multi-stage sampling design accounting for 4 health regions and 14 parishes using enumeration districts as primary sampling units. Means and proportions of the variables of interest were compared between various categories. Non-response was defined as failure to provide an analyzable response. Linear and logistic regression models accounting for sample design and post-stratification weighting were used to identify independent correlates of recruitment efficiency and item non-response. We recruited 2012 15-74 year-olds (66.2% females) at a response rate of 87.6% with significant variation between regions (80.9% to 97.6%; p < 0.0001). Females outnumbered males in all parishes. The majority of subjects were recruited in a single visit, 39.1% required multiple visits varying significantly by region (27.0% to 49.8% [p < 0.0001]). Average interview time was 44.3 minutes with no variation between health regions, urban-rural residence, educational level, gender and SES; but increased significantly with older age category from 42.9 minutes in the youngest to 46.0 minutes in the oldest age category. Between 15.8% and 26.8% of persons did not provide responses for the number of sexual partners in the last year. Women and urban residents provided less data than their counterparts. Highest item non-response related to income at 30% with no gender difference but independently related to educational level, employment status, age group and health region. Characteristics of non-responders vary with types of questions. Informative health surveys are possible in developing countries. While survey response rates may be satisfactory, item non-response was high in respect of income and sexual practice. In contrast to developed countries, non-response to questions on income is higher and has different correlates. These findings can inform future surveys.

Exploring Physician Perspectives of Residency Holdover Handoffs: A Qualitative Study to Understand an Increasingly Important Type of Handoff.

PubMed

Duong, Jonathan A; Jensen, Trevor P; Morduchowicz, Sasha; Mourad, Michelle; Harrison, James D; Ranji, Sumant R

2017-06-01

The term "holdover admissions" refers to patients admitted by an overnight physician and whose care is then transferred to a new primary team the next morning. Descriptions of the holdover process in internal medicine are sparse. To identify important factors affecting the quality of holdover handoffs at an internal medicine (IM) residency program and to compare them to previously identified factors for other handoffs. We undertook a qualitative study using structured focus groups and interviews. We analyzed data using qualitative content analysis. IM residents, IM program directors, and hospitalists at a large academic medical center. A nine-question open-ended interview guide. We identified 13 factors describing holdover handoffs. Five factors-physical space, standardization, task accountability, closed-loop verification, and resilience-were similar to those described in prior handoff literature in other specialties. Eight factors were new concepts that may uniquely affect the quality of the holdover handoff in IM. These included electronic health record access, redundancy, unwritten thoughts, different clinician needs, diagnostic uncertainty, anchoring, teaching, and feedback. These factors were organized into five overarching themes: physical environment, information transfer, responsibility, clinical reasoning, and education. The holdover handoff in IM is complex and has unique considerations for achieving high quality. Further exploration of safe, efficient, and educational holdover handoff practices is necessary.

Exploring the challenges of the Iranian parliament about passing laws for resource allocation in healthcare: a qualitative study

PubMed Central

Mohsenpour, Seyed Ramezan; Arab, Mohammad; Razavi, Seyed Hasan Emami; Sari, Ali Akbari

2017-01-01

Background Awareness about the process of law making and the factors that affect the legislative process have an important role in improving legislations that are approved by parliaments. Objective This study aimed to explore and analyze the process of development and enactment of law in Iran’s parliament, and factors that might affect the enactment of laws that are related to the allocation and distribution of health sector resources in Iran. Methods In this case study, data were collected through review of literature and national documents, and experts’ interviews. Interviews were performed with selected members of parliament (MPs), ex members of parliament and professionals from the Ministry of Health and Medical Education (MOHME) (15 persons). MAX QDA 10 was used for coding and constructing themes. Data were analyzed in five steps (familiarization, developing a conceptual framework, coding, indexing, and interpretation) using a content analysis with inductive and deductive approaches. Results The main factors that could affect the approval and enactment of legislations related to allocation of healthcare resources in the Iranian parliament were categorized in seven themes including: Importance of issue, resource availability, legislator’s awareness about the topic, lobbying and unofficial relations with influential officials, mentioning strong reasons by MOHME, weakness of previous laws, and positive feedback related to the same laws. Conclusion Although the process of law making in parliament, and implementation of them in health organizations have legal stages, the study showed that several key factors affect this trend. In fact, it is suggested the health policy makers and MPs consider extending a range of factors to improve the process of law making and the efficiency of legislation related to allocation of healthcare resources. PMID:29238478

Exploring the challenges of the Iranian parliament about passing laws for resource allocation in healthcare: a qualitative study.

PubMed

Mohsenpour, Seyed Ramezan; Arab, Mohammad; Razavi, Seyed Hasan Emami; Sari, Ali Akbari

2017-10-01

Awareness about the process of law making and the factors that affect the legislative process have an important role in improving legislations that are approved by parliaments. This study aimed to explore and analyze the process of development and enactment of law in Iran's parliament, and factors that might affect the enactment of laws that are related to the allocation and distribution of health sector resources in Iran. In this case study, data were collected through review of literature and national documents, and experts' interviews. Interviews were performed with selected members of parliament (MPs), ex members of parliament and professionals from the Ministry of Health and Medical Education (MOHME) (15 persons). MAX QDA 10 was used for coding and constructing themes. Data were analyzed in five steps (familiarization, developing a conceptual framework, coding, indexing, and interpretation) using a content analysis with inductive and deductive approaches. The main factors that could affect the approval and enactment of legislations related to allocation of healthcare resources in the Iranian parliament were categorized in seven themes including: Importance of issue, resource availability, legislator's awareness about the topic, lobbying and unofficial relations with influential officials, mentioning strong reasons by MOHME, weakness of previous laws, and positive feedback related to the same laws. Although the process of law making in parliament, and implementation of them in health organizations have legal stages, the study showed that several key factors affect this trend. In fact, it is suggested the health policy makers and MPs consider extending a range of factors to improve the process of law making and the efficiency of legislation related to allocation of healthcare resources.

E-beam column monitoring for improved CD SEM stability and tool matching

NASA Astrophysics Data System (ADS)

Hayes, Timothy S.; Henninger, Randall S.

2000-06-01

Tool matching is an important metric for in-line semiconductor metrology systems. The ability to obtain the same measurement results on two or more systems allows a semiconductor fabrication facility (fab) to deploy product in an efficient manner improving overall equipment efficiency (OEE). Many parameters on the critical dimension scanning electron microscopes (CDSEMs) can affect the long-term precision component to the tool-matching metric. One such class of parameters is related to the electron beam column stability. The alignment and condition of the gun and apertures, as well as astigmatism correction, have all been found to affect the overall measurements of the CDSEM. These effects are now becoming dominant factors in sub-3nm tool-matching criteria. This paper discusses the methodologies of column parameter monitoring and actions and controls for improving overall stability. Results have shown that column instabilities caused by contamination, gun fluctuations, component failures, detector efficiency, and external issues can be identified through parameter monitoring. The Applied Materials (AMAT) 7830 Series CDSEMs evaluated at IBM's Burlington, Vermont manufacturing facility have demonstrated 5 nm tool matching across 11 systems, which has resulted in non-dedicated product deployment and has significantly reduced cost of ownership.

The productivity and cost-efficiency of models for involving nurse practitioners in primary care: a perspective from queueing analysis.

PubMed

Liu, Nan; D'Aunno, Thomas

2012-04-01

To develop simple stylized models for evaluating the productivity and cost-efficiencies of different practice models to involve nurse practitioners (NPs) in primary care, and in particular to generate insights on what affects the performance of these models and how. The productivity of a practice model is defined as the maximum number of patients that can be accounted for by the model under a given timeliness-to-care requirement; cost-efficiency is measured by the corresponding annual cost per patient in that model. Appropriate queueing analysis is conducted to generate formulas and values for these two performance measures. Model parameters for the analysis are extracted from the previous literature and survey reports. Sensitivity analysis is conducted to investigate the model performance under different scenarios and to verify the robustness of findings. Employing an NP, whose salary is usually lower than a primary care physician, may not be cost-efficient, in particular when the NP's capacity is underutilized. Besides provider service rates, workload allocation among providers is one of the most important determinants for the cost-efficiency of a practice model involving NPs. Capacity pooling among providers could be a helpful strategy to improve efficiency in care delivery. The productivity and cost-efficiency of a practice model depend heavily on how providers organize their work and a variety of other factors related to the practice environment. Queueing theory provides useful tools to take into account these factors in making strategic decisions on staffing and panel size selection for a practice model. © Health Research and Educational Trust.

Analysis of the Effects of Residual Strains and Defects on Skin/Stiffener Debonding using Decohesion Elements

NASA Technical Reports Server (NTRS)

Davila, Carlos G.; Camanho, Pedro P.

2003-01-01

Delamination is one of the predominant forms of failure in laminated composites especially when there is no reinforcement in the thickness direction. To develop composite structures that are more damage tolerant, it is necessary to understand how delamination develops and how it can affect the residual performance. A number of factors such as residual thermal strains, matrix curing shrinkage, and manufacturing defects affect how damage will grow in a composite structure. It is important to develop analysis methods that are computationally efficient that can account for all such factors. The objective of the current work is to apply a newly developed decohesion element to investigate the debond strength of skin/stiffener composite specimens. The process of initiation of delaminations and the propagation of delamination fronts is investigated. The numerical predictions are compared with published experimental results.

SEMICONDUCTOR TECHNOLOGY: An efficient dose-compensation method for proximity effect correction

NASA Astrophysics Data System (ADS)

Ying, Wang; Weihua, Han; Xiang, Yang; Renping, Zhang; Yang, Zhang; Fuhua, Yang

2010-08-01

A novel simple dose-compensation method is developed for proximity effect correction in electron-beam lithography. The sizes of exposed patterns depend on dose factors while other exposure parameters (including accelerate voltage, resist thickness, exposing step size, substrate material, and so on) remain constant. This method is based on two reasonable assumptions in the evaluation of the compensated dose factor: one is that the relation between dose factors and circle-diameters is linear in the range under consideration; the other is that the compensated dose factor is only affected by the nearest neighbors for simplicity. Four-layer-hexagon photonic crystal structures were fabricated as test patterns to demonstrate this method. Compared to the uncorrected structures, the homogeneity of the corrected hole-size in photonic crystal structures was clearly improved.

Stomatal and non-stomatal factors regulated the photosynthesis of soybean seedlings in the present of exogenous bisphenol A.

PubMed

Jiao, Liya; Wang, Lihong; Zhou, Qing; Huang, Xiaohua

2017-11-01

Bisphenol A (BPA) is an emerging environmental endocrine disruptor that has toxic effects on plants growth. Photosynthesis supplies the substances and energy required for plant growth, and regulated by stomatal and non-stomatal factors. Therefore, in this study, to reveal how BPA affects photosynthesis in soybean seedlings (Glycine max L.) from the perspective of stomatal and non-stomatal factors, the stomatal factors (stomatal conductance and behaviours) and non-stomatal factors (Hill reaction, apparent quantum efficiency, Rubisco activity, carboxylation efficiency, the maximum Rubisco carboxylation velocity, ribulose-1,5-bisphospate regeneration capacities mediated by maximum electron transport rates, and triose phosphate utilization rate) were investigated using a portable photosynthesis system. Moreover, the pollution of BPA in the environment was simulated. The results indicate that low-dose BPA enhanced net photosynthetic rate (P n ) primarily by promoting stomatal factors, resulting in increased relative growth rates and accelerated soybean seedling growth. High-dose BPA decreases the P n by simultaneously inhibiting stomatal and non-stomatal factors, and this inhibition decreases the relative growth rates further reducing soybean seedling growth. Following the withdrawal of BPA, all of the indices were restored to varying degrees. In conclusion, low-dose BPA increased the P n by promoting stomatal factors while high-dose BPA decreased the P n by simultaneously inhibiting stomatal and non-stomatal factors. These findings provide a model (or, hypothesis) for the effects of BPA on plant photosynthesis. Copyright © 2017 Elsevier Inc. All rights reserved.

Combining Heavy Ion Radiation and Artificial MicroRNAs to Target the Homologous Recombination Repair Gene Efficiently Kills Human Tumor Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng Zhiming; Department of Radiation Oncology, School of Medicine, Winship Cancer Institute, Emory University, Atlanta, Georgia; Wang Ping

2013-02-01

Purpose: Previously, we demonstrated that heavy ions kill more cells at the same dose than X-rays because DNA-clustered lesions produced by heavy ions affect nonhomologous end-joining (NHEJ) repair but not homologous recombination repair (HRR). We have also shown that our designed artificial microRNAs (amiRs) could efficiently target XRCC4 (an essential factor for NHEJ) or XRCC2 (an essential factor for HRR) and sensitize human tumor cells to X-rays. Based on these data, we were interested in testing the hypothesis that combining heavy ions and amiRs to target HRR but not NHEJ should more efficiently kill human tumor cells. Methods and Materials:more » Human tumor cell lines (U87MG, a brain tumor cell line, and A549, a lung cancer cell line) and their counterparts, overexpressed with amiR to target XRCC2, XRCC4 or both, were used in this study. Survival sensitivities were examined using a clonogenic assay after these cells were exposed to X-rays or heavy ions. In addition, these cell lines were subcutaneously injected into nude mice to form xenografts and the tumor size was compared after the tumor areas were exposed to X-rays or heavy ions. Results: Although targeting either XRCC4 (NHEJ factor) or XRCC2 (HRR factor) sensitized the human tumor cells to X-rays, in vitro and the xenograft animal model, targeting only XRCC2 but not XRCC4 sensitized the human tumor cells to heavy ions in vitro and in the xenograft animal model. Conclusions: Combining heavy ions with targeting the HRR pathway, but not the NHEJ pathway, could significantly improve the efficiency of tumor cell death.« less

Combining heavy ion radiation and artificial microRNAs to target the homologous recombination repair gene efficiently kills human tumor cells.

PubMed

Zheng, Zhiming; Wang, Ping; Wang, Hongyan; Zhang, Xiangming; Wang, Minli; Cucinotta, Francis A; Wang, Ya

2013-02-01

Previously, we demonstrated that heavy ions kill more cells at the same dose than X-rays because DNA-clustered lesions produced by heavy ions affect nonhomologous end-joining (NHEJ) repair but not homologous recombination repair (HRR). We have also shown that our designed artificial microRNAs (amiRs) could efficiently target XRCC4 (an essential factor for NHEJ) or XRCC2 (an essential factor for HRR) and sensitize human tumor cells to X-rays. Based on these data, we were interested in testing the hypothesis that combining heavy ions and amiRs to target HRR but not NHEJ should more efficiently kill human tumor cells. Human tumor cell lines (U87MG, a brain tumor cell line, and A549, a lung cancer cell line) and their counterparts, overexpressed with amiR to target XRCC2, XRCC4 or both, were used in this study. Survival sensitivities were examined using a clonogenic assay after these cells were exposed to X-rays or heavy ions. In addition, these cell lines were subcutaneously injected into nude mice to form xenografts and the tumor size was compared after the tumor areas were exposed to X-rays or heavy ions. Although targeting either XRCC4 (NHEJ factor) or XRCC2 (HRR factor) sensitized the human tumor cells to X-rays, in vitro and the xenograft animal model, targeting only XRCC2 but not XRCC4 sensitized the human tumor cells to heavy ions in vitro and in the xenograft animal model. Combining heavy ions with targeting the HRR pathway, but not the NHEJ pathway, could significantly improve the efficiency of tumor cell death. Copyright © 2013 Elsevier Inc. All rights reserved.

Monogenic Disorders of Adrenal Steroidogenesis.

PubMed

Baranowski, Elizabeth S; Arlt, Wiebke; Idkowiak, Jan

2018-06-06

Disorders of adrenal steroidogenesis comprise autosomal recessive conditions affecting steroidogenic enzymes of the adrenal cortex. Those are located within the 3 major branches of the steroidogenic machinery involved in the production of mineralocorticoids, glucocorticoids, and androgens. This mini review describes the principles of adrenal steroidogenesis, including the newly appreciated 11-oxygenated androgen pathway. This is followed by a description of pathophysiology, biochemistry, and clinical implications of steroidogenic disorders, including mutations affecting cholesterol import and steroid synthesis, the latter comprising both mutations affecting steroidogenic enzymes and co-factors required for efficient catalysis. A good understanding of adrenal steroidogenic pathways and their regulation is crucial as the basis for sound management of these disorders, which in the majority present in early childhood. © 2018 The Author(s) Published by S. Karger AG, Basel.

Affective-cognitive meta-bases versus structural bases of attitudes predict processing interest versus efficiency.

PubMed

See, Ya Hui Michelle; Petty, Richard E; Fabrigar, Leandre R

2013-08-01

We proposed that (a) processing interest for affective over cognitive information is captured by meta-bases (i.e., the extent to which people subjectively perceive themselves to rely on affect or cognition in their attitudes) and (b) processing efficiency for affective over cognitive information is captured by structural bases (i.e., the extent to which attitudes are more evaluatively congruent with affect or cognition). Because processing speed can disentangle interest from efficiency by being manifest as longer or shorter reading times, we hypothesized and found that more affective meta-bases predicted longer affective than cognitive reading time when processing efficiency was held constant (Study 1). In contrast, more affective structural bases predicted shorter affective than cognitive reading time when participants were constrained in their ability to allocate resources deliberatively (Study 2). When deliberation was neither encouraged nor constrained, effects for meta-bases and structural bases emerged (Study 3). Implications for affective-cognitive processing and other attitudes-relevant constructs are discussed.

Ground-water heat pumps: An examination of hydrogeologic, environmental, legal, and economic factors affecting their use. Volume 1: Main text, appendices A, B, and C

NASA Astrophysics Data System (ADS)

Armitage, D. M.; Bacon, D. J.; Massey-Norton, J. T.; Miller, J. M.

1980-11-01

Groundwater is attractive as a potential low temperature energy source in residential space conditioning applications. When used in conjunction with a heat pump, ground water can serve as both a heat source and a heat sink. Major hydrogeologic aspects that affect system use include groundwater temperature and availability at shallow depths as these factors influence operational efficiency. Ground water quality is considered as it affects the performance and life expectancy of the water side heat exchanger. Environmental impacts related to groundwater heat pump system use are most influenced by water use and disposal methods. In general, recharge to the subsurface is recommended. Legal restrictions on system use are often stricter at the municipal and county levels than at state and federal levels. Computer simulations indicate that under a variety of climatologic conditions, groundwater heat pumps use less energy than conventional heating and cooling equipment. Life cycle cost comparisons with conventional equipment depend on alternative system choices and well cost options included in the groundwater heat pump system.

Influence of the ambient temperature on the cooling efficiency of the high performance cooling device with thermosiphon effect

NASA Astrophysics Data System (ADS)

Nemec, Patrik; Malcho, Milan

2018-06-01

This work deal with experimental measurement and calculation cooling efficiency of the cooling device working with a heat pipe technology. The referred device in the article is cooling device capable transfer high heat fluxes from electric elements to the surrounding. The work contain description, working principle and construction of cooling device. The main factor affected the dissipation of high heat flux from electronic elements through the cooling device to the surrounding is condenser construction, its capacity and option of heat removal. Experimental part describe the measuring method cooling efficiency of the cooling device depending on ambient temperature in range -20 to 40°C and at heat load of electronic components 750 W. Measured results are compared with results calculation based on physical phenomena of boiling, condensation and natural convection heat transfer.

Study of vesicle size distribution dependence on pH value based on nanopore resistive pulse method

NASA Astrophysics Data System (ADS)

Lin, Yuqing; Rudzevich, Yauheni; Wearne, Adam; Lumpkin, Daniel; Morales, Joselyn; Nemec, Kathleen; Tatulian, Suren; Lupan, Oleg; Chow, Lee

2013-03-01

Vesicles are low-micron to sub-micron spheres formed by a lipid bilayer shell and serve as potential vehicles for drug delivery. The size of vesicle is proposed to be one of the instrumental variables affecting delivery efficiency since the size is correlated to factors like circulation and residence time in blood, the rate for cell endocytosis, and efficiency in cell targeting. In this work, we demonstrate accessible and reliable detection and size distribution measurement employing a glass nanopore device based on the resistive pulse method. This novel method enables us to investigate the size distribution dependence of pH difference across the membrane of vesicles with very small sample volume and rapid speed. This provides useful information for optimizing the efficiency of drug delivery in a pH sensitive environment.

Some factors affecting efficiencies of n-CdS/p-CdTe thin film solar cells

NASA Astrophysics Data System (ADS)

Morris, G. C.; Das, S. K.; Tanner, P. G.

1992-02-01

Electrodeposited CdS and CdTe thin films have been fabricated into solar cells with a CdS/CdTe heterojunction. The CdTe films were made by varying two parameters, viz. the concentration of tellurium ions in the deposition solution and the quasi-rest potential (QRP) of the deposit. The properties of the completed cells were examined as a function of those preparation variables. Cell efficiency varied with both QRP and tellurium ion concentration. Whilst chemical analytic methods showed no compositional variation between cells, morphological studies showed that the most efficient cells had the largest grain size. Electrical and capacitance measurements were used to show that the density of interband states and of junction interface states increased with structural imperfection. The major losses in the solar cell parameters increased with increased polycrystalline structure.

New rules of thumb maximizing energy efficiency in street lighting with discharge lamps: The general equations for lighting design

NASA Astrophysics Data System (ADS)

Peña-García, A.; Gómez-Lorente, D.; Espín, A.; Rabaza, O.

2016-06-01

New relationships between energy efficiency, illuminance uniformity, spacing and mounting height in public lighting installations were derived from the analysis of a large sample of outputs generated with a widely used software application for lighting design. These new relationships greatly facilitate the calculation of basic lighting installation parameters. The results obtained are also based on maximal energy efficiency and illuminance uniformity as a premise, which are not included in more conventional methods. However, these factors are crucial since they ensure the sustainability of the installations. This research formulated, applied and analysed these new equations. The results of this study highlight their usefulness in rapid planning and urban planning in developing countries or areas affected by natural disasters where engineering facilities and computer applications for this purpose are often unavailable.

"You can save time if…"—A qualitative study on internal factors slowing down clinical trials in Sub-Saharan Africa

PubMed Central

Pfeiffer, Constanze; Limacher, Manuela; Burri, Christian

2017-01-01

Background The costs, complexity, legal requirements and number of amendments associated with clinical trials are rising constantly, which negatively affects the efficient conduct of trials. In Sub-Saharan Africa, this situation is exacerbated by capacity and funding limitations, which further increase the workload of clinical trialists. At the same time, trials are critically important for improving public health in these settings. The aim of this study was to identify the internal factors that slow down clinical trials in Sub-Saharan Africa. Here, factors are limited to those that exclusively relate to clinical trial teams and sponsors. These factors may be influenced independently of external conditions and may significantly increase trial efficiency if addressed by the respective teams. Methods We conducted sixty key informant interviews with clinical trial staff working in different positions in two clinical research centres in Kenya, Ghana, Burkina Faso and Senegal. The study covered English- and French-speaking, and Eastern and Western parts of Sub-Saharan Africa. We performed thematic analysis of the interview transcripts. Results We found various internal factors associated with slowing down clinical trials; these were summarised into two broad themes, “planning” and “site organisation”. These themes were consistently mentioned across positions and countries. “Planning” factors related to budget feasibility, clear project ideas, realistic deadlines, understanding of trial processes, adaptation to the local context and involvement of site staff in planning. “Site organisation” factors covered staff turnover, employment conditions, career paths, workload, delegation and management. Conclusions We found that internal factors slowing down clinical trials are of high importance to trial staff. Our data suggest that adequate and coherent planning, careful assessment of the setting, clear task allocation and management capacity strengthening may help to overcome the identified internal factors and allow clinical trials to proceed more efficiently. PMID:28301530

An ERP study of conflict monitoring in 4–8-year old children: Associations with temperament

PubMed Central

Buss, Kristin A.; Dennis, Tracy A.; Brooker, Rebecca J.; Sippel, Lauren M.

2011-01-01

Although there is great interest in identifying the neural correlates of cognitive processes that create risk for psychopathology, there is a paucity of research in young children. One event-related potential (ERP), the N2, is thought to index conflict monitoring and has been linked cognitive and affective risk factors for anxiety. Most of this research, however, has been conducted with adults, adolescents, and older children, but not with younger children. To address this gap, the current study examined 26 4–8-year-olds, who completed a cued flanker task while EEG was continuously recorded. We assessed whether the N2 was detectable in this group of young children and examined associations between the N2 and factors reflecting affective risk (e.g., reduced executive attention, temperamental effortful control, and temperamental surgency). We documented an N2 effect (greater N2 amplitude to incongruent versus congruent flankers), but only in children older than 6 years of age. Increases in the N2 effect were associated with less efficient executive attention and lower temperamental effortful control. We discuss the implications of these findings and consider how they may inform future studies on biomarkers for cognitive and affective risk factors for anxiety. PMID:21666879

Exo-reversible staging of coolers in series and in parallel

NASA Astrophysics Data System (ADS)

Maytal, Ben-Zion

2017-10-01

Serial and parallel staging of exo-reversible coolers are formulated, analyzed and compared. The parallel staging includes an extensive parameter which is the proportion of combined stages. This extensive free parameter affects the intensive factors of specific power and figure of merit. Serial staging reduces the 1st Law efficiency and parallel staging improves the 2nd Law efficiency. Comparison of a parallel with a serial staging under common cooling capacity and cooling range, shows that it is always possible to find a parallel arrangement of lower specific power and more compact. Some results are demonstrated on staging of Joule-Thomson cryocoolers (below and above the Joule-Thomson inversion temperature).

An Analytical and Experimental Analysis of Factors Affecting Exhaust System Performance in Sea Level Static Jet Engine Test Facilities.

DTIC Science & Technology

1972-12-01

include filtering devices, venturi scrubbers , and electrostatic precipitators. These have been evaluated as unsatisfactory from considerations of...Early studies of pollution abatement systems have resulted in the selection and development of a nucleation scrubber [Ref. 47]. Other devices analyzed...the venturi system is its inability to operate efficiently over greater than a 10 percent interval away from its design point, which is an

A Study of Air Force Company Grade Officer Value Systems in Selected Career Fields and Their Correlation with Career Intentions.

DTIC Science & Technology

1989-09-01

Groups of People Employee Welfare Government High Productivity Nanagers Organizational Efficiency Ne ny Boss Personal Goals of Individuals Ideas...34, . . there is general agreement that the satisfaction or thwarting of expectations has pronounced effects on employee motivation" (19:27). He states...that factors other than job satisfaction, such as environmental affects, contribute to employee retention (19:35). In conclusion Nadia states that

A History of the Development of the Navy Medical Department’s Workload Management System for Nursing.

DTIC Science & Technology

1987-08-01

efficient and rational methodology. Young, Giovannetti, Lewison , and Thomas (1981) offer the following comprehensive definition of a staffing methodology... Johns Hopkins Hospital. Connor used industrial engineering techniques, such as work sampling, time and motion studies, and continuous observation, to time...ADA 109883-ADA 109886). Young, J.P., Giovannetti, P., Lewison , D., & Thomas, M.L. Factors Affecting Nurse Staffing in Acute Care Hospitals: A Review

Extending the Endurance, Missions and Capabilities of Most UAVs Using Advanced Flexible/Ridged Solar Cells and New High Power Density Batteries Technology

DTIC Science & Technology

2011-03-01

68 3. Photovoltaic Effect ..........................69 4. Factors Affecting Cell Efficiency ............69 D. THIN-FILM...resistance. (After [3])...........................................120  xvi Table 21.  Average battery capacity (AH) and battery energy capacity (WH...which is directly limited by the on-board battery capacity . The other key drawbacks are the weight and size of the mini- xviii UAV, which restrict the

Analyses of Blood Bank Efficiency, Cost-Effectiveness and Quality

NASA Astrophysics Data System (ADS)

Lam, Hwai-Tai Chen

In view of the increasing costs of hospital care, it is essential to investigate methods to improve the labor efficiency and the cost-effectiveness of the hospital technical core in order to control costs while maintaining the quality of care. This study was conducted to develop indices to measure efficiency, cost-effectiveness, and the quality of blood banks; to identify factors associated with efficiency, cost-effectiveness, and quality; and to generate strategies to improve blood bank labor efficiency and cost-effectiveness. Indices developed in this study for labor efficiency and cost-effectiveness were not affected by patient case mix and illness severity. Factors that were associated with labor efficiency were identified as managerial styles, and organizational designs that balance workload and labor resources. Medical directors' managerial involvement was not associated with labor efficiency, but their continuing education and specialty in blood bank were found to reduce the performance of unnecessary tests. Surprisingly, performing unnecessary tests had no association with labor efficiency. This suggested the existence of labor slack in blood banks. Cost -effectiveness was associated with workers' benefits, wages, and the production of high-end transfusion products by hospital-based donor rooms. Quality indices used in this study included autologous transfusion rates, platelet transfusion rates, and the check points available in an error-control system. Because the autologous transfusion rate was related to patient case mix, severity of illness, and possible inappropriate transfusion, it was not recommended to be used for quality index. Platelet-pheresis transfusion rates were associated with the transfusion preferences of the blood bank medical directors. The total number of check points in an error -control system was negatively associated with government ownership and workers' experience. Recommendations for improving labor efficiency and cost-effectiveness were focused on an incentive system that encourages team effort, and the use of appropriate measurements for laboratory efficiency and operational system designs.

Factors Affecting Physicians’ Responses to Patients’ Requests for Antidepressants: Focus Group Study

PubMed Central

Silberman, Jordan; Paterniti, Debora A.; Kravitz, Richard L.; Epstein, Ronald M.

2007-01-01

Background The ways in which patients’ requests for antidepressants affect physicians’ prescribing behavior are poorly understood. Objective To describe physicians’ affective and cognitive responses to standardized patients’ (SPs) requests for antidepressants, as well as the attitudinal and contextual factors influencing prescribing behavior. Design Focus group interviews and brief demographic questionnaires. Participants Twenty-two primary care physicians in 6 focus groups; all had participated in a prior RCT of the influence of patients’ requests on physicians’ prescribing. Measurements Iterative review of interview transcripts, involving qualitative coding and thematic analysis. Results Physicians participating in the focus groups were frequently unaware of and denied the degree to which their thinking was biased by patient requests, but were able to recognize such biases after facilitated reflection. Common affective responses included annoyance and empathy. Common cognitive reactions resulted in further diagnostic inquiry or in acquiescing to the patient’s demands to save time or build the patient–clinician relationship. Patients’ requests for medication prompted the participants to err on the side of overtreating versus careful review of clinical indications. Lack of time and participants’ attitudes—toward the role of the patient and the pharmaceutical ads—also influenced their responses, prompting them to interpret patient requests as diagnostic clues or opportunities for efficiency. Conclusions This study provides a taxonomy of affective and cognitive responses to patients’ requests for medications and the underlying attitudes and contextual factors influencing them. Improved capacity for moment-to-moment self-awareness during clinical reasoning processes may increase the appropriateness of prescribing. PMID:17987348

Assessing the efficiency of hospital pharmacy services in Thai public district hospitals.

PubMed

Rattanachotphanit, Thananan; Limwattananon, Chulaporn; Limwattananon, Supon; Johns, Jeff R; Schommer, Jon C; Brown, Lawrence M

2008-07-01

The purpose of this study was to assess the efficiency of hospital pharmacy services and to determine the environmental factors affecting pharmacy service efficiency. The technical efficiency of a hospital pharmacy was assessed to evaluate the hospital's ability to use pharmacy manpower in order to produce the maximum output of the pharmacy service. Data Envelopment Analysis (DEA) was used as an efficiency measurement. The two labor inputs were pharmacists and support personnel and the ten outputs were from four pharmacy activities: drug dispensing, drug purchasing and inventory control, patient-oriented activities, and health consumer protection services. This was used to estimate technical efficiency. A Tobit regression model was used to determine the effect of the hospital size, location, input mix of pharmacy staff, working experience of pharmacists at the study hospitals, and use of technology on the pharmacy service efficiency. Data for pharmacy service input and output quantities were obtained from 155 respondents. Nineteen percent were found to have full efficiency with a technical efficiency score of 1.00. Thirty-six percent had a technical efficiency score of 0.80 or above and 27% had a low technical efficiency score (< 0.60). The average TE score increased in respect to the hospital size (0.60, 0.71, 0.75, and 0.83 in 10, 30, 60, and 90-120 bed hospitals, respectively). Hospital size and geographic location were significantly associated with pharmacy service efficiency.

Effects of a Cancer Prevention Advertisement on Beliefs and Knowledge about Cancer Prevention.

PubMed

Kye, Su Yeon; Yoo, Jisu; Lee, Min Hee; Jun, Jae Kwan

2015-01-01

Outcome-expectation beliefs and knowledge may ultimately influence behavior for cancer prevention. The aims of this study were to measure changes in knowledge and beliefs about cancer prevention before and after viewing a television advertisement and identify the factors affecting receptivity to its messages. A one-group pretest-posttest design was used in this study of 1,000 individuals aged 20 to 65 years who were recruited online in November 2014. The outcome variables included cancer prevention beliefs based on the Health Belief Model (five items) and knowledge about risk factors for cancer (seven items). Perceived susceptibility, perceived benefits, and self-efficacy increased significantly and their perceived severity and perceived barriers decreased significantly, after participants viewed the television advertisement. Correct responses to questions about risk factors also increased significantly, except for smoking. The main factors affecting changes in the outcome variables were age, interest in cancer prevention, social network, satisfaction with the ad, and pretest scores. Television advertisements with positive frameworks can be an efficient channel of improving beliefs and knowledge about cancer prevention in a short period. The continuous development of intervention materials that consider the demographics, needs, and satisfaction of the target group will be necessary for future studies.

Genetic factors affecting dental caries risk.

PubMed

Opal, S; Garg, S; Jain, J; Walia, I

2015-03-01

This article reviews the literature on genetic aspects of dental caries and provides a framework for the rapidly changing disease model of caries. The scope is genetic aspects of various dental factors affecting dental caries. The PubMed database was searched for articles with keywords 'caries', 'genetics', 'taste', 'diet' and 'twins'. This was followed by extensive handsearching using reference lists from relevant articles. The post-genomic era will present many opportunities for improvement in oral health care but will also present a multitude of challenges. We can conclude from the literature that genes have a role to play in dental caries; however, both environmental and genetic factors have been implicated in the aetiology of caries. Additional studies will have to be conducted to replicate the findings in a different population. Identification of genetic risk factors will help screen and identify susceptible patients to better understand the contribution of genes in caries aetiopathogenesis. Information derived from these diverse studies will provide new tools to target individuals and/or populations for a more efficient and effective implementation of newer preventive measures and diagnostic and novel therapeutic approaches in the management of this disease. © 2015 Australian Dental Association.

Effects of lanthanum and acid rain stress on the bio-sequestration of lanthanum in phytoliths in germinated rice seeds

PubMed Central

Si, Yong; Wang, Lihong; Huang, Xiaohua

2018-01-01

REEs in the environment can be absorbed by plants and sequestered by plant phytoliths. Acid rain can directly or indirectly affect plant physiological functions. Currently, the effects of REEs and acid rain on phytolith-REEs complex in plants are not yet fully understood. In this study, a high-silicon accumulation crop, rice (Oryza sativa L.), was selected as a representative of plants, and orthogonal experiments were conducted under various levels of lanthanum [La(III)] and pH. The results showed that various La(III) concentrations could significantly improve the efficiency and sequestration of phytolith La(III) in germinated rice seeds. A pH of 4.5 promoted phytolith La(III) sequestration, while a pH of 3.5 inhibited sequestration. Compared with the single treatment with La(III), the combination of La(III) and acid rain inhibited the efficiency and sequestration of phytolith La(III). Correlation analysis showed that the efficiency of phytolith La(III) sequestration had no correlation with the production of phytolith but was closely correlated with the sequestration of phytolith La(III) and the physiological changes of germinated rice seeds. Phytolith morphology was an important factor affecting phytolith La(III) sequestration in germinated rice seeds, and the effect of tubes on sequestration was more significant than that of dumbbells. This study demonstrated that the formation of the phytolith and La(III) complex could be affected by exogenous La(III) and acid rain in germinated rice seeds. PMID:29763463

Studying DNA looping by single-molecule FRET.

PubMed

Le, Tung T; Kim, Harold D

2014-06-28

Bending of double-stranded DNA (dsDNA) is associated with many important biological processes such as DNA-protein recognition and DNA packaging into nucleosomes. Thermodynamics of dsDNA bending has been studied by a method called cyclization which relies on DNA ligase to covalently join short sticky ends of a dsDNA. However, ligation efficiency can be affected by many factors that are not related to dsDNA looping such as the DNA structure surrounding the joined sticky ends, and ligase can also affect the apparent looping rate through mechanisms such as nonspecific binding. Here, we show how to measure dsDNA looping kinetics without ligase by detecting transient DNA loop formation by FRET (Fluorescence Resonance Energy Transfer). dsDNA molecules are constructed using a simple PCR-based protocol with a FRET pair and a biotin linker. The looping probability density known as the J factor is extracted from the looping rate and the annealing rate between two disconnected sticky ends. By testing two dsDNAs with different intrinsic curvatures, we show that the J factor is sensitive to the intrinsic shape of the dsDNA.

Studying DNA Looping by Single-Molecule FRET

PubMed Central

Le, Tung T.; Kim, Harold D.

2014-01-01

Bending of double-stranded DNA (dsDNA) is associated with many important biological processes such as DNA-protein recognition and DNA packaging into nucleosomes. Thermodynamics of dsDNA bending has been studied by a method called cyclization which relies on DNA ligase to covalently join short sticky ends of a dsDNA. However, ligation efficiency can be affected by many factors that are not related to dsDNA looping such as the DNA structure surrounding the joined sticky ends, and ligase can also affect the apparent looping rate through mechanisms such as nonspecific binding. Here, we show how to measure dsDNA looping kinetics without ligase by detecting transient DNA loop formation by FRET (Fluorescence Resonance Energy Transfer). dsDNA molecules are constructed using a simple PCR-based protocol with a FRET pair and a biotin linker. The looping probability density known as the J factor is extracted from the looping rate and the annealing rate between two disconnected sticky ends. By testing two dsDNAs with different intrinsic curvatures, we show that the J factor is sensitive to the intrinsic shape of the dsDNA. PMID:24998459

Animal and management factors influencing grower and finisher pig performance and efficiency in European systems: a meta-analysis.

PubMed

Douglas, S L; Szyszka, O; Stoddart, K; Edwards, S A; Kyriazakis, I

2015-07-01

A meta-analysis on the effects of management and animal-based factors on the performance and feed efficiency of growing pigs can provide information on single factor and interaction effects absent in individual studies. This study analysed the effects of such factors on average daily gain (ADG), feed intake (FI) and feed conversion ratio (FCR) of grower and finisher pigs. The multivariate models identified significant effects of: (1) bedding (P<0.01), stage of growth (P<0.001) and the interaction bedding×lysine (P<0.001) on ADG. ADG was higher on straw compared with no bedding (710 v. 605 g/day). (2) FI was significantly affected by stage of growth (P<0.01), bedding (P<0.01), group composition (P<0.05), group size (P<0.01), feed CP content (P<0.01), ambient temperature (P<0.01) and the interaction between floor space and feed energy content (P<0.001). Pigs housed on straw had a lower FI in comparison with those without (1.44 v. 2.04 kg/day); a higher FI was seen for pigs separated by gender in comparison with mixed groups (2.05 v. 1.65 kg/day); FI had a negative linear relationship with group size, the CP content of the feed and ambient temperature. (3) Stage of growth (P<0.001), feed CP (P<0.001) and lysine content (P<0.001), ambient temperature (P<0.001) and feed crude fibre (CF) content (P<0.01) significantly affected FCR; there were no significant interactions between any factors on this trait. There was an improvement in FCR at higher ambient temperatures, increased feed CP and lysine content, but a deterioration of FCR at higher CF contents. For ADG, the interaction of bedding×lysine was caused by pigs housed without bedding (straw) having higher ADG when on a feed lower in lysine, whereas those with bedding had a higher ADG when on a feed higher in lysine. Interaction effects on FI were caused by animals with the least amount of floor space having a higher FI when given a feed with a low metabolisable energy (ME) content, in contrast to all other pigs, which showed a higher FI with increased ME content. The meta-analysis confirmed the significant effect of several well-known factors on the performance and efficiency of grower and finisher pigs, the effects of some less established ones and, importantly, the interactions between such factors.

Arabidopsis BPM Proteins Function as Substrate Adaptors to a CULLIN3-Based E3 Ligase to Affect Fatty Acid Metabolism in Plants[W

PubMed Central

Chen, Liyuan; Lee, Joo Hyun; Weber, Henriette; Tohge, Takayuki; Witt, Sandra; Roje, Sanja; Fernie, Alisdair R.; Hellmann, Hanjo

2013-01-01

Regulation of transcriptional processes is a critical mechanism that enables efficient coordination of the synthesis of required proteins in response to environmental and cellular changes. Transcription factors require accurate activity regulation because they play a critical role as key mediators assuring specific expression of target genes. In this work, we show that CULLIN3-based E3 ligases have the potential to interact with a broad range of ETHYLENE RESPONSE FACTOR (ERF)/APETALA2 (AP2) transcription factors, mediated by MATH-BTB/POZ (for Meprin and TRAF [tumor necrosis factor receptor associated factor] homolog)-Broad complex, Tramtrack, Bric-a-brac/Pox virus and Zinc finger) proteins. The assembly with an E3 ligase causes degradation of their substrates via the 26S proteasome, as demonstrated for the WRINKLED1 ERF/AP2 protein. Furthermore, loss of MATH-BTB/POZ proteins widely affects plant development and causes altered fatty acid contents in mutant seeds. Overall, this work demonstrates a link between fatty acid metabolism and E3 ligase activities in plants and establishes CUL3-based E3 ligases as key regulators in transcriptional processes that involve ERF/AP2 family members. PMID:23792371

A computer program for calculating relative-transmissivity input arrays to aid model calibration

USGS Publications Warehouse

Weiss, Emanuel

1982-01-01

A program is documented that calculates a transmissivity distribution for input to a digital ground-water flow model. Factors that are taken into account in the calculation are: aquifer thickness, ground-water viscosity and its dependence on temperature and dissolved solids, and permeability and its dependence on overburden pressure. Other factors affecting ground-water flow are indicated. With small changes in the program code, leakance also could be calculated. The purpose of these calculations is to provide a physical basis for efficient calibration, and to extend rational transmissivity trends into areas where model calibration is insensitive to transmissivity values.

High efficiency and good beam quality of electro-optic, cavity-dumped and double-end pumped Nd:YLF laser

NASA Astrophysics Data System (ADS)

Tang, X. X.; Fan, Z. W.; Qiu, J. S.; Lian, F. Q.; Zhang, X. L.

2012-06-01

In this paper, we describe a Nd:YLF laser based on high-speed RTP electro-optical cavity dumping technique. Two home-made 150 W fiber pump modules are used from both sides to pump Nd:YLF crystal. Coupling systems are the key elements in end-pumped solid-state lasers, the aberrations of which greatly affect the efficiency of the lasers. In order to get high efficient and good quality laser output, the optical software ZEMAX is used to design a four-piece coupling system. When the pumped energy is 32 mJ at the repetition rate of 1 Hz, the output energy is 6.5 mJ with 2.5 ns pulse width. When the pumped energy is 13.1 W at the repetition rate of 200 Hz, the output energy is 2.2 W with small M 2 factor where M {/x 2} is 1.04, and M {/y 2} is 1.05, and the light-light conversion efficiency is up to 16.8%.

High-efficiency AlxGa1-xAs/GaAs cathode for photon-enhanced thermionic emission solar energy converters

NASA Astrophysics Data System (ADS)

Feng, Cheng; Zhang, Yijun; Qian, Yunsheng; Wang, Ziheng; Liu, Jian; Chang, Benkang; Shi, Feng; Jiao, Gangcheng

2018-04-01

A theoretical emission model for AlxGa1-xAs/GaAs cathode with complex structure based on photon-enhanced thermionic emission is developed by utilizing one-dimensional steady-state continuity equations. The cathode structure comprises a graded-composition AlxGa1-xAs window layer and an exponential-doping GaAs absorber layer. In the deduced model, the physical properties changing with the Al composition are taken into consideration. Simulated current-voltage characteristics are presented and some important factors affecting the conversion efficiency are also illustrated. Compared with the graded-composition and uniform-doping cathode structure, and the uniform-composition and uniform-doping cathode structure, the graded-composition and exponential-doping cathode structure can effectively improve the conversion efficiency, which is ascribed to the twofold built-in electric fields. More strikingly, this graded bandgap structure is especially suitable for photon-enhanced thermionic emission devices since a higher conversion efficiency can be achieved at a lower temperature.

Optical determination of Shockley-Read-Hall and interface recombination currents in hybrid perovskites

PubMed Central

Sarritzu, Valerio; Sestu, Nicola; Marongiu, Daniela; Chang, Xueqing; Masi, Sofia; Rizzo, Aurora; Colella, Silvia; Quochi, Francesco; Saba, Michele; Mura, Andrea; Bongiovanni, Giovanni

2017-01-01

Metal-halide perovskite solar cells rival the best inorganic solar cells in power conversion efficiency, providing the outlook for efficient, cheap devices. In order for the technology to mature and approach the ideal Shockley-Queissier efficiency, experimental tools are needed to diagnose what processes limit performances, beyond simply measuring electrical characteristics often affected by parasitic effects and difficult to interpret. Here we study the microscopic origin of recombination currents causing photoconversion losses with an all-optical technique, measuring the electron-hole free energy as a function of the exciting light intensity. Our method allows assessing the ideality factor and breaks down the electron-hole recombination current into bulk defect and interface contributions, providing an estimate of the limit photoconversion efficiency, without any real charge current flowing through the device. We identify Shockley-Read-Hall recombination as the main decay process in insulated perovskite layers and quantify the additional performance degradation due to interface recombination in heterojunctions. PMID:28317883

Impact of technical and technological changes on energy efficiency of production company - case study

NASA Astrophysics Data System (ADS)

Szwedzka, K.; Gruszka, J.; Szafer, P.

2016-08-01

Improving energy efficiency is one of the strategic objectives of the European Union for rational energy economy. To make efforts to improve energy efficiency have been obliged both small and large end-users. This article aims to show the possibilities of improving energy efficiency by introducing technical and technological process changes of pine lumber drying. The object of the research is process of drying lumber implemented in a production company, which is a key supplier of large furniture manufacturer. Pine lumber drying chamber consume about 45% of total electricity in sawmill. According to various sources, drying of 1m3 of lumber uses about 3060kWh and is dependent of inter alia: the drying process itself, the factors affecting the processing time and the desired output moisture content of the timber. The article proposals for changes in the process of drying lumber pine have been positively validated in the company, and as a result their energy consumption per 1 m3 of product declined by 18%.

Optimization of Dish Solar Collectors with and without Secondary Concentrators

NASA Technical Reports Server (NTRS)

Jaffe, L. D.

1982-01-01

Methods for optimizing parabolic dish solar collectors and the consequent effects of various optical, thermal, mechanical, and cost variables are examined. The most important performance optimization is adjusting the receiver aperture to maximize collector efficiency. Other parameters that can be adjusted to optimize efficiency include focal length, and, if a heat engine is used, the receiver temperature. The efficiency maxima associated with focal length and receiver temperature are relatively broad; it may, accordingly, be desirable to design somewhat away from the maxima. Performance optimization is sensitive to the slope and specularity errors of the concentrator. Other optical and thermal variables affecting optimization are the reflectance and blocking factor of the concentrator, the absorptance and losses of the receiver, and, if a heat engine is used, the shape of the engine efficiency versus temperature curve. Performance may sometimes be improved by use of an additional optical element (a secondary concentrator) or a receiver window if the errors of the primary concentrator are large or the receiver temperature is high.

Boosters and barriers for direct cardiac reprogramming.

PubMed

Talkhabi, Mahmood; Zonooz, Elmira Rezaei; Baharvand, Hossein

2017-06-01

Heart disease is currently the most significant cause of morbidity and mortality worldwide, which accounts for approximately 33% of all deaths. Recently, a promising and alchemy-like strategy has been developed called direct cardiac reprogramming, which directly converts somatic cells such as fibroblasts to cardiac lineage cells such as cardiomyocytes (CMs), termed induced CMs or iCMs. The first in vitro cardiac reprogramming study, mediated by cardiac transcription factors (TFs)-Gata4, Tbx5 and Mef2C-, was not enough efficient to produce an adequate number of fully reprogrammed, functional iCMs. As a result, numerous combinations of cardiac TFs exist for direct cardiac reprogramming of mouse and human fibroblasts. However, the efficiency of direct cardiac reprogramming remains low. Recently, a number of cellular and molecular mechanisms have been identified to increase the efficiency of direct cardiac reprogramming and the quality of iCMs. For example, microgrooved substrate, cardiogenic growth factors [VEGF, FGF, BMP4 and Activin A], and an appropriate stoichiometry of TFs boost the direct cardiac reprogramming. On the other hand, serum, TGFβ signaling, activators of epithelial to mesenchymal transition, and some epigenetic factors (Bmi1 and Ezh2) are barriers for direct cardiac reprogramming. Manipulating these mechanisms by the application of boosters and removing barriers can increase the efficiency of direct cardiac reprogramming and possibly make iCMs reliable for cell-based therapy or other potential applications. In this review, we summarize the latest trends in cardiac TF- or miRNA-based direct cardiac reprogramming and comprehensively discuses all molecular and cellular boosters and barriers affecting direct cardiac reprogramming. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnostic throughput factor analysis for en-route airspace and optimal aircraft trajectory generation based on capacity prediction and controller workload

NASA Astrophysics Data System (ADS)

Shin, Sanghyun

Today's National Airspace System (NAS) is approaching its limit to efficiently cope with the increasing air traffic demand. Next Generation Air Transportation System (NextGen) with its ambitious goals aims to make the air travel more predictable with fewer delays, less time sitting on the ground and holding in the air to improve the performance of the NAS. However, currently the performance of the NAS is mostly measured using delay-based metrics which do not capture a whole range of important factors that determine the quality and level of utilization of the NAS. The factors affecting the performance of the NAS are themselves not well defined to begin with. To address these issues, motivated by the use of throughput-based metrics in many areas such as ground transportation, wireless communication and manufacturing, this thesis identifies the different factors which majorly affect the performance of the NAS as demand (split into flight cancellation and flight rerouting), safe separation (split into conflict and metering) and weather (studied as convective weather) through careful comparison with other applications and performing empirical sensitivity analysis. Additionally, the effects of different factors on the NAS's performance are quantitatively studied using real traffic data with the Future ATM Concepts Evaluation Tool (FACET) for various sectors and centers of the NAS on different days. In this thesis we propose a diagnostic tool which can analyze the factors that have greater responsibility for regions of poor and better performances of the NAS. Based on the throughput factor analysis for en-route airspace, it was found that weather and controller workload are the major factors that decrease the efficiency of the airspace. Also, since resources such as air traffic controllers, infrastructure and airspace are limited, it is becoming increasingly important to use the available resources efficiently. To alleviate the impact of the weather and controller workload while optimally utilizing limited resources, various aircraft rerouting strategies for Air Traffic Management (ATM) have been proposed. However, the number of rerouting tools available to address these issues for the center-level and the National Airspace System (NAS) are relatively less compared with the tools for the sector-level and terminal airspace. Additionally, previous works consider the airspace containing the weather as no-fly zones instead of reduced-traffic zones and do not explicitly consider controller workload when generating aircraft trajectories to avoid the weather-affected airspace, thereby reducing the overall performance of the airspace. In this thesis, a new rerouting algorithm for the center-level airspace is proposed to address these problems by introducing a feedback loop connecting a tactical rerouting algorithm with a strategic rerouting algorithm using dynamic programming and a modified A* algorithm respectively. This helps reduce the computational cost significantly while safely handling a large number of aircraft. In summary, this thesis suggests the ways in which the NAS's performance can be further improved, thereby supporting various concepts envisioned by the Next Generation Air Transportation System (NextGen) and providing vital information which can be used for suitable economic and environmental advantages.

Extensive investigation of the sap flow of maize plants in an oasis farmland in the middle reach of the Heihe River, Northwest China.

PubMed

Zhao, Liwen; He, Zhibin; Zhao, Wenzhi; Yang, Qiyue

2016-09-01

A better understanding of the sap flow characteristics of maize plants is critical for improving irrigation water-use efficiency, especially for regions facing water resource shortages. In this study, sap flow rates, related soil-physics and plant-growth parameters, and meteorological factors, were simultaneously monitored in a maize field in two consecutive years, 2011 and 2012, and the sap flow rates of the maize plants were extensively analyzed based on the monitored data. Seasonal and daily variational characteristics were identified at different growth stages and under different weather conditions, respectively. The analyses on the relationships between sap flow rate and reference evapotranspiration (ET0), as well as several plant-growth parameters, indicate that the irrigation schedule can exert an influence on sap flow, and can consequently affect crop yield. The ranking of the main meteorological factors affecting the sap flow rate was: net radiation > air temperature > vapor pressure deficit > wind speed. For a quick estimation of sap flow rates, an empirical formula based on the two top influencing factors was put forward and verified to be reliable. The sap flow rate appeared to show little response to irrigation when the water content was relatively high, implying that some of the irrigation in recent years may have been wasted. These results may help to reveal the bio-physical processes of maize plants related to plant transpiration, which could be beneficial for establishing an efficient irrigation management system in this region and also for providing a reference for other maize-planting regions.

A study of the effects of innovative and efficient practices on the performance of hospice care organizations.

PubMed

Kirby, Eric G; Keeffe, Michael J; Nicols, Kay M

2007-01-01

Due to changes in social norms, funding initiatives, and other environmental factors, the business of hospice care has significantly evolved over the past 40 years. There has been an influx of for-profit firms, increased consolidation, and significant funding changes. We have witnessed a growth in utilization rates, an increase in insurance coverage, and improved governmental funding. Hospice care organizations have responded to these pressures by pursuing more efficient and innovative business practices. Drawing upon institutional theory, this study seeks to address whether quality of care provided to hospice patients is affected as organizations respond to environmental pressures for innovative and efficient business practices. This study uses hierarchical regression to analyze data from 111 hospices in California. Innovative practices are positively related to quality of care. However, efficient practices have no significant relationship with quality of care. It appears that incorporating innovative practices is positively related to quality of care. Although cost containment may be necessary for continued survival, efficiency improvement efforts do not seem to lead to improved quality of care.

Removal of Cu2+ and turbidity from wastewater by mercaptoacetyl chitosan.

PubMed

Chang, Qing; Zhang, Min; Wang, Jinxi

2009-09-30

A macromolecule heavy metal flocculant mercaptoacetyl chitosan (MAC) was prepared by reacting chitosan with mercaptoacetic acid. In preliminary experiments, the flocculation performance of MAC was evaluated by using wastewater containing Cu(2+) or/and turbidity. Some factors which affect the removal of Cu(2+) and turbidity were also studied. The experimental results showed that: (1) MAC can remove both Cu(2+) and turbidity from wastewater. The removal efficiency of Cu(2+) by using MAC combined with hydrolyzed polyacrylamide is higher than that by only using MAC, the removal efficiency of Cu(2+) reaches above 98%; (2) when water sample containing not only Cu(2+) but also turbidity-causing substance, the removal efficiency of both Cu(2+) and turbidity will be promoted by the cooperation effect of each other, the residual concentration of Cu(2+) reaches below 0.5 mg L(-1) and the turbidity reaches below 3NTU, Cu(2+) is more easily removed by MAC when turbidity is higher; (3) the removal efficiency of Cu(2+) increases with the increase in pH value, contrarily removal efficiency of turbidity decreases with the increase in pH value.

Effect of fluorescent particle size on the modulation efficiency of ultrasound-modulated fluorescence.

PubMed

Liu, Yuan; Yuan, Baohong; Vignola, Joseph

2012-01-01

To investigate whether the size of fluorescent particles affects the modulation efficiency of ultrasound-modulated fluorescence (UMF), we measured UMF and DC (direct current) signals of the fluorescence emission from four different sized fluorescent particles: (1) three carboxylate-modified fluorescent microspheres (FM) with diameters of 20 nm, 200 nm, and 1.0 µm and (2) streptavidin-conjugated Alexa Fluor 647 with a diameter of approximately 5 nm. The UMF and DC signals were simultaneously measured using a broadband lock-in amplifier and a narrowband amplifier, respectively. The ratio of the UMF strength to the DC signal strength is defined as the modulation efficiency. This modulation efficiency was then used to evaluate the effects of fluorophore size and concentration. Results show that the modulation efficiency was improved by approximately a factor of two when the size of the fluorescent particles is increased from 5 nm to 1 µm. In addition, the linear relationship between the UMF strength and ultrasound pressure (observed in our previous study) were maintained regardless of the fluorescent particle sizes.

Effect of fluorescent particle size on the modulation efficiency of ultrasound-modulated fluorescence

PubMed Central

Liu, Yuan; Yuan, Baohong; Vignola, Joseph

2013-01-01

To investigate whether the size of fluorescent particles affects the modulation efficiency of ultrasound-modulated fluorescence (UMF), we measured UMF and DC (direct current) signals of the fluorescence emission from four different sized fluorescent particles: (1) three carboxylate-modified fluorescent microspheres (FM) with diameters of 20 nm, 200 nm, and 1.0 µm and (2) streptavidin-conjugated Alexa Fluor 647 with a diameter of approximately 5 nm. The UMF and DC signals were simultaneously measured using a broadband lock-in amplifier and a narrowband amplifier, respectively. The ratio of the UMF strength to the DC signal strength is defined as the modulation efficiency. This modulation efficiency was then used to evaluate the effects of fluorophore size and concentration. Results show that the modulation efficiency was improved by approximately a factor of two when the size of the fluorescent particles is increased from 5 nm to 1 µm. In addition, the linear relationship between the UMF strength and ultrasound pressure (observed in our previous study) were maintained regardless of the fluorescent particle sizes. PMID:24179476

The Productivity and Cost-Efficiency of Models for Involving Nurse Practitioners in Primary Care: A Perspective from Queueing Analysis

PubMed Central

Liu, Nan; D'Aunno, Thomas

2012-01-01

Objective To develop simple stylized models for evaluating the productivity and cost-efficiencies of different practice models to involve nurse practitioners (NPs) in primary care, and in particular to generate insights on what affects the performance of these models and how. Data Sources and Study Design The productivity of a practice model is defined as the maximum number of patients that can be accounted for by the model under a given timeliness-to-care requirement; cost-efficiency is measured by the corresponding annual cost per patient in that model. Appropriate queueing analysis is conducted to generate formulas and values for these two performance measures. Model parameters for the analysis are extracted from the previous literature and survey reports. Sensitivity analysis is conducted to investigate the model performance under different scenarios and to verify the robustness of findings. Principal Findings Employing an NP, whose salary is usually lower than a primary care physician, may not be cost-efficient, in particular when the NP's capacity is underutilized. Besides provider service rates, workload allocation among providers is one of the most important determinants for the cost-efficiency of a practice model involving NPs. Capacity pooling among providers could be a helpful strategy to improve efficiency in care delivery. Conclusions The productivity and cost-efficiency of a practice model depend heavily on how providers organize their work and a variety of other factors related to the practice environment. Queueing theory provides useful tools to take into account these factors in making strategic decisions on staffing and panel size selection for a practice model. PMID:22092009

Factorizing the motion sensitivity function into equivalent input noise and calculation efficiency.

PubMed

Allard, Rémy; Arleo, Angelo

2017-01-01

The photopic motion sensitivity function of the energy-based motion system is band-pass peaking around 8 Hz. Using an external noise paradigm to factorize the sensitivity into equivalent input noise and calculation efficiency, the present study investigated if the variation in photopic motion sensitivity as a function of the temporal frequency is due to a variation of equivalent input noise (e.g., early temporal filtering) or calculation efficiency (ability to select and integrate motion). For various temporal frequencies, contrast thresholds for a direction discrimination task were measured in presence and absence of noise. Up to 15 Hz, the sensitivity variation was mainly due to a variation of equivalent input noise and little variation in calculation efficiency was observed. The sensitivity fall-off at very high temporal frequencies (from 15 to 30 Hz) was due to a combination of a drop of calculation efficiency and a rise of equivalent input noise. A control experiment in which an artificial temporal integration was applied to the stimulus showed that an early temporal filter (generally assumed to affect equivalent input noise, not calculation efficiency) could impair both the calculation efficiency and equivalent input noise at very high temporal frequencies. We conclude that at the photopic luminance intensity tested, the variation of motion sensitivity as a function of the temporal frequency was mainly due to early temporal filtering, not to the ability to select and integrate motion. More specifically, we conclude that photopic motion sensitivity at high temporal frequencies is limited by internal noise occurring after the transduction process (i.e., neural noise), not by quantal noise resulting from the probabilistic absorption of photons by the photoreceptors as previously suggested.

Effects of temperature, algae biomass and ambient nutrient on the absorption of dissolved nitrogen and phosphate by Rhodophyte Gracilaria asiatica

NASA Astrophysics Data System (ADS)

Du, Rongbin; Liu, Liming; Wang, Aimin; Wang, Yongqiang

2013-03-01

Gracilaria asiatica, being highly efficient in nutrient absorption, is cultivated in sea cucumber ponds to remove nutrients such as nitrogen and phosphate. It was cultured in a laboratory simulating field conditions, and its nutrient absorption was measured to evaluate effects of environmental conditions. Ammonia nitrogen (AN), nitrate nitrogen (NN), total inorganic nitrogen (TIN), and soluble reactive phosphorus (SRP) uptake rate and removal efficiency were determined in a 4×2 factorial design experiment in water temperatures ( T) at 15°C and 25°C, algae biomass (AB) at 0.5 g/L and 1.0 g/L, total inorganic nitrogen (TIN) at 30 μmol/L and 60 μmol/L, and soluble reactive phosphorus (SRP) at 3 and 6 μmol/L. AB and ambient TIN or SRP levels significantly affected uptake rate and removal efficiency of AN, NN, TIN, and SRP ( P< 0.001). G. asiatica in AB of 0.5 g/L showed higher uptake rate and lower removal efficiency relative to that with AB of 1.0 g/L. Nitrogen and phosphorus uptake rate rose with increasing ambient nutrient concentrations; nutrient removal efficiency decreased at higher environmental nutrient concentrations. The algae preferred to absorb AN to NN. Uptake rates of AN, NN, and SRP were significantly affected by temperature ( P < 0.001); uptake rate was higher for the 25°C group than for the 15°C group at the initial experiment stage. Only the removal efficiency of AN and SRP showed a significant difference between the two temperature groups ( P< 0.01). The four factors had significant interactive effects on absorption of N and P, implying that G. asiatica has great bioremedial potential in sea cucumber culture ponds.

Perceptual load in different regions of the visual scene and its relevance for driving.

PubMed

Marciano, Hadas; Yeshurun, Yaffa

2015-06-01

The aim of this study was to better understand the role played by perceptual load, at both central and peripheral regions of the visual scene, in driving safety. Attention is a crucial factor in driving safety, and previous laboratory studies suggest that perceptual load is an important factor determining the efficiency of attentional selectivity. Yet, the effects of perceptual load on driving were never studied systematically. Using a driving simulator, we orthogonally manipulated the load levels at the road (central load) and its sides (peripheral load), while occasionally introducing critical events at one of these regions. Perceptual load affected driving performance at both regions of the visual scene. Critically, the effect was different for central versus peripheral load: Whereas load levels on the road mainly affected driving speed, load levels on its sides mainly affected the ability to detect critical events initiating from the roadsides. Moreover, higher levels of peripheral load impaired performance but mainly with low levels of central load, replicating findings with simple letter stimuli. Perceptual load has a considerable effect on driving, but the nature of this effect depends on the region of the visual scene at which the load is introduced. Given the observed importance of perceptual load, authors of future studies of driving safety should take it into account. Specifically, these findings suggest that our understanding of factors that may be relevant for driving safety would benefit from studying these factors under different levels of load at different regions of the visual scene. © 2014, Human Factors and Ergonomics Society.

Impact of the Local Public Hospital Reform on the Efficiency of Medium-Sized Hospitals in Japan: An Improved Slacks-Based Measure Data Envelopment Analysis Approach.

PubMed

Zhang, Xing; Tone, Kaoru; Lu, Yingzhe

2018-04-01

To assess the change in efficiency and total factor productivity (TFP) of the local public hospitals in Japan after the local public hospital reform launched in late 2007, which was aimed at improving the financial capability and operational efficiency of hospitals. Secondary data were collected from the Ministry of Internal Affairs and Communications on 213 eligible medium-sized hospitals, each operating 100-400 beds from FY2006 to FY2011. The improved slacks-based measure nonoriented data envelopment analysis models (Quasi-Max SBM nonoriented DEA models) were used to estimate dynamic efficiency score and Malmquist Index. The dynamic efficiency measure indicated an efficiency gain in the first several years of the reform and then was followed by a decrease. Malmquist Index analysis showed a significant decline in the TFP between 2006 and 2011. The financial improvement of medium-sized hospitals was not associated with enhancement of efficiency. Hospital efficiency was not significantly different among ownership structure and law-application system groups, but it was significantly affected by hospital location. The results indicate a need for region-tailored health care policies and for a more comprehensive reform to overcome the systemic constraints that might contribute to the decline of the TFP. © Health Research and Educational Trust.

Large incidence angle and defocus influence cat's eye retro-reflector

NASA Astrophysics Data System (ADS)

Zhang, Lai-xian; Sun, Hua-yan; Zhao, Yan-zhong; Yang, Ji-guang; Zheng, Yong-hui

2014-11-01

Cat's eye lens make the laser beam retro-reflected exactly to the opposite direction of the incidence beam, called cat's eye effect, which makes rapid acquiring, tracking and pointing of free space optical communication possible. Study the influence of cat's eye effect to cat's eye retro-reflector at large incidence angle is useful. This paper analyzed the process of how the incidence angle and focal shit affect effective receiving area, retro-reflected beam divergence angle, central deviation of cat's eye retro-reflector at large incidence angle and cat's eye effect factor using geometrical optics method, and presented the analytic expressions. Finally, numerical simulation was done to prove the correction of the study. The result shows that the efficiency receiving area of cat's eye retro-reflector is mainly affected by incidence angle when the focal shift is positive, and it decreases rapidly when the incidence angle increases; the retro-reflected beam divergence and central deviation is mainly affected by focal shift, and within the effective receiving area, the central deviation is smaller than beam divergence in most time, which means the incidence beam can be received and retro-reflected to the other terminal in most time. The cat's eye effect factor gain is affected by both incidence angle and focal shift.

Evaluation of NASA-sponsored research on capital investment decision making in the civil aviation industry

NASA Technical Reports Server (NTRS)

Donovan, D. J.

1977-01-01

Significant findings of three studies undertaken to provide the NASA Aircraft Energy Efficiency (ACEE) Office with information regarding how aircraft manufacturers and commercial airlines make investment decisions concerning the acquisition of new and derivative technology are analyzed and their general implications explored. Topics discussed include: the market for airline aircraft, factors affecting the corporate decision making process of air transport manufacturers, and flight equipment purchasing practices of representative air carriers.

Ion implantation enhanced metal-Si-metal photodetectors

NASA Astrophysics Data System (ADS)

Sharma, A. K.; Scott, K. A. M.; Brueck, S. R. J.; Zolper, J. C.; Myers, D. R.

1994-05-01

The quantum efficiency and frequency response of simple Ni-Si-Ni metal-semiconductor-metal (MSM) photodetectors at long wavelengths are significantly enhanced with a simple, ion-implantation step to create a highly absorbing region approx. 1 micron below the Si surface. The internal quantum efficiency is improved by a factor of approx. 3 at 860 nm (to 64%) and a full factor of ten at 1.06 microns (to 23%) as compared with otherwise identical unimplanted devices. Dark currents are only slightly affected by the implantation process and are as low as 630 pA for a 4.5-micron gap device at 10-V bias. Dramatic improvement in the impulse response is observed, 100 ps vs. 600 ps, also at 10-V bias and 4.5-micron gap, due to the elimination of carrier diffusion tails in the implanted devices. Due to its planar structure, this device is fully VLSI compatible. Potential applications include optical interconnections for local area networks and multi-chip modules.

A prediction method of ice breaking resistance using a multiple regression analysis

NASA Astrophysics Data System (ADS)

Cho, Seong-Rak; Lee, Sungsu

2015-07-01

The two most important tasks of icebreakers are first to secure a sailing route by breaking the thick sea ice and second to sail efficiently herself for purposes of exploration and transportation in the polar seas. The resistance of icebreakers is a priority factor at the preliminary design stage; not only must their sailing efficiency be satisfied, but the design of the propulsion system will be directly affected. Therefore, the performance of icebreakers must be accurately calculated and evaluated through the use of model tests in an ice tank before construction starts. In this paper, a new procedure is developed, based on model tests, to estimate a ship's ice breaking resistance during continuous ice-breaking in ice. Some of the factors associated with crushing failures are systematically considered in order to correctly estimate her ice-breaking resistance. This study is intended to contribute to the improvement of the techniques for ice resistance prediction with ice breaking ships.

Evaluation of mercury speciation and removal through air pollution control devices of a 190 MW boiler.

PubMed

Wu, Chengli; Cao, Yan; Dong, Zhongbing; Cheng, Chinmin; Li, Hanxu; Pan, Weiping

2010-01-01

Air pollution control devices (APCDs) are installed at coal-fired power plants for air pollutant regulation. Selective catalytic reduction (SCR) and wet flue gas desulfurization (FGD) systems have the co-benefits of air pollutant and mercury removal. Configuration and operational conditions of APCDs and mercury speciation affect mercury removal efficiently at coal-fired utilities. The Ontario Hydro Method (OHM) recommended by the U.S. Environmental Protection Agency (EPA) was used to determine mercury speciation simultaneously at five sampling locations through SCR-ESP-FGD at a 190 MW unit. Chlorine in coal had been suggested as a factor affecting the mercury speciation in flue gas; and low-chlorine coal was purported to produce less oxidized mercury (Hg2+) and more elemental mercury (Hg0) at the SCR inlet compared to higher chlorine coal. SCR could oxidize elemental mercury into oxidized mercury when SCR was in service, and oxidation efficiency reached 71.0%. Therefore, oxidized mercury removal efficiency was enhanced through a wet FGD system. In the non-ozone season, about 89.5%-96.8% of oxidized mercury was controlled, but only 54.9%-68.8% of the total mercury was captured through wet FGD. Oxidized mercury removal efficiency was 95.9%-98.0%, and there was a big difference in the total mercury removal efficiencies from 78.0% to 90.2% in the ozone season. Mercury mass balance was evaluated to validate reliability of OHM testing data, and the ratio of mercury input in the coal to mercury output at the stack was from 0.84 to 1.08.

Treatment Outcome Following Transarterial Chemoembolization in Advanced Bone and Soft Tissue Sarcomas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Chunyu; Wang, Jianbo, E-mail: a602131499@163.com; Wang, Yonggang

PurposeTransarterial chemoembolization (TACE) is used to treat unresectable bone and soft tissue sarcoma (STS) and as a pre-surgical adjuvant treatment. However, its efficiency for advanced STS is undetermined. This study evaluated TACE’s efficiency in treating advanced STS and prognostic factors for patient survival.Materials and MethodsWe enrolled 39 patients with unresectable STS who underwent TACE as an alternative treatment during 2010–2014, with overall survival (OS) as the primary end point. Cancer pain was evaluated by visual analogue scores (VAS) before and after TACE procedures. Factors that affect survival were evaluated by multivariate analyses (Cox proportional hazard model).ResultsMean OS after TACE wasmore » 23.7 ± 2.1 months, with 1-year OS 71.5 %, 2-year OS 45.8 %, and 3-year OS 32.5 %. Lesion number and tumor stage were key predictors of survival. TACE was found to decrease cancer pain VAS and increase relapse interval. Size of polyvinyl alcohol (PVA) particle diameter (P = 0.03) and imaging response (P = 0.044) were also found to affect relapse interval.ConclusionTACE was an effective treatment for advanced STS, with a 32.5 % 3-year OS rate, and led to lower cancer pain VAS and longer relapse intervals than chemoinfusion only. Smaller PVA particles are preferable during the TACE procedure.« less

Smoke and fire characteristics for cerrado and deforestation burns in Brazil: BASE-B experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ward, D.E.; Susott, R.A.; Babbitt, R.E.

1992-09-20

Fires of the tropical forests and savannas are a major source of particulate matter and trace gases affecting the atmosphere globally. A paucity of quantitative information exists for these ecosystems with respect to fuel biomass, smoke emissions, and fire behavior conditions affecting the release of emissions. Five test fires were performed during August and September 1990 in the cerrado (savannalike region) in central Brazil (three fires) and tropical moist forest (two fires) in the eastern Amazon. This paper details the gases released, the ratios of the gases to each other and to particulate matter, fuel loads and the fraction consumedmore » (combustion factors), and the fire behavior associated with biomass consumption. Models are presented for evaluating emission factors for CH{sub 4}, CO{sub 2}, CO, H{sub 2}, and particles less than 2.5 {mu}m diameter (PM2.5) as a function of combustion efficiency. The ratio of carbon released as CO{sub 2} (combustion efficiency) for the cerrado fires averaged 0.94 and for the deforestation fires it decreased from 0.88 for the flaming phase to <0.80 during the smoldering phase of combustion. For tropical ecosystems, emissions of most products of incomplete combustion are projected to be lower than previous estimates for savanna ecosystems and somewhat higher for fires used for deforestation purposes. 59 refs., 9 figs., 10 tabs.« less

A multiple chamber, semicontinuous, crop carbon dioxide exchange system: design, calibration, and data interpretation

NASA Technical Reports Server (NTRS)

van Iersel, M. W.; Bugbee, B.

2000-01-01

Long-term, whole crop CO2 exchange measurements can be used to study factors affecting crop growth. These factors include daily carbon gain, cumulative carbon gain, and carbon use efficiency, which cannot be determined from short-term measurements. We describe a system that measures semicontinuously crop CO2 exchange in 10 chambers over a period of weeks or months. Exchange of CO2 in every chamber can be measured at 5 min intervals. The system was designed to be placed inside a growth chamber, with additional environmental control provided by the individual gas exchange chambers. The system was calibrated by generating CO2 from NaHCO3 inside the chambers, which indicated that accuracy of the measurements was good (102% and 98% recovery for two separate photosynthesis systems). Since the systems measure net photosynthesis (P-net, positive) and dark respiration(R-dark, negative), the data can be used to estimate gross photosynthesis, daily carbon gain, cumulative carbon gain, and carbon use efficiency. Continuous whole-crop measurements are a valuable tool that complements leaf photosynthesis measurements. Multiple chambers allow for replication and comparison among several environmental or cultural treatments that may affect crop growth. Example data from a 2 week study with petunia (Petunia x hybrida Hort. Vilm.-Andr.) are presented to illustrate some of the capabilities of this system.

Factors affecting the efficiency of embryo transfer in the domestic ferret (Mustela putorius furo).

PubMed

Li, Ziyi; Sun, Xingshen; Chen, Juan; Leno, Gregory H; Engelhardt, John F

2006-07-15

Embryo transfer (ET) to recipient females is a foundational strategy for a number of assisted reproductive technologies, including cloning by somatic cell nuclear transfer. In an attempt to develop efficient ET in domestic ferrets, factors affecting development of transferred embryo were investigated. Unilateral and bilateral transfer of zygotes or blastocysts in the oviduct or uterus was evaluated in recipient nulliparous or primiparous females. Developing fetuses were collected from recipient animals 21 days post-copulation and examined. The percentage of fetal formation was different (P<0.05) for unilateral and bilateral transfer of zygotes (71%) in nulliparous females with bilateral transfer (56%) in primiparous recipients. The percentage (90%) of fetal formation in nulliparous recipients following unilateral transfer of blastocysts was higher (P<0.05) than that observed in primiparous recipients with bilateral ET (73%). Notably, the percentage of fetal formation was higher (P<0.05) when blastocyts were transferred as compared to zygotes (90% versus 71%). Transuterine migration of embryos occurred following all unilateral transfers and also in approximately 50% of bilateral transfers with different number of embryos in each uterine horn. These data will help to facilitate the development of assisted reproductive strategies in the ferret and could lead to the use of this species for modeling human disease and for conservation of the endangered Mustelidae species such as black-footed ferret and European mink.

Factors affecting the efficiency of embryo transfer in the domestic ferret (Mustela putorius furo)

PubMed Central

Li, Ziyi; Sun, Xingshen; Chen, Juan; Leno, Gregory H.; Engelhardt, John F.

2007-01-01

Embryo transfer (ET) to recipient females is a foundational strategy for a number of assisted reproductive technologies, including cloning by somatic cell nuclear transfer. In an attempt to develop efficient ET in domestic ferrets, factors affecting development of transferred embryo were investigated. Unilateral and bilateral transfer of zygotes or blastocysts in the oviduct or uterus was evaluated in recipient nulliparous or primiparous females. Developing fetuses were collected from recipient animals 21 days post-copulation and examined. The percentage of fetal formation was different (P < 0.05) for unilateral and bilateral transfer of zygotes (71%) in nulliparous females with bilateral transfer (56%) in primiparous recipients. The percentage (90%) of fetal formation in nulliparous recipients following unilateral transfer of blastocysts was higher (P < 0.05) than that observed in primiparous recipients with bilateral ET (73%). Notably, the percentage of fetal formation was higher (P < 0.05) when blastocyts were transferred as compared to zygotes (90% versus 71%). Transuterine migration of embryos occurred following all unilateral transfers and also in approximately 50% of bilateral transfers with different number of embryos in each uterine horn. These data will help to facilitate the development of assisted reproductive strategies in the ferret and could lead to the use of this species for modeling human disease and for conservation of the endangered Mustelidae species such as black-footed ferret and European mink. PMID:16330092

DOE Office of Scientific and Technical Information (OSTI.GOV)

Isić, Goran, E-mail: isicg@ipb.ac.rs; Gajić, Radoš

It is well known that due to the high conductivity of noble metals at terahertz frequencies and scalability of macroscopic Maxwell equations, a geometrical downscaling of a terahertz resonator results in the linear upscaling of its resonance frequency. However, the scaling laws of modal decay rates, important for the resonator excitation efficiency, are much less known. Here, we investigate the extent to which the scale-invariance of decay rates is violated due to the finite conductivity of the metal. We find that the resonance quality factor or the excitation efficiency may be substantially affected by scaling and show that this happensmore » as a result of the scale-dependence of the metal absorption rate, while the radiative decay and the dielectric cavity absorption rates are approximately scale-invariant. In particular, we find that by downscaling overcoupled resonators, their excitation efficiency increases, while the opposite happens with undercoupled resonators.« less

Highly efficient removal of ammonia nitrogen from wastewater by dielectrophoresis-enhanced adsorption.

PubMed

Liu, Dongyang; Cui, Chenyang; Wu, Yanhong; Chen, Huiying; Geng, Junfeng; Xia, Jianxin

2018-01-01

A new approach, based on dielectrophoresis (DEP), was developed in this work to enhance traditional adsorption for the removal of ammonia nitrogen (NH 3 -N) from wastewater. The factors that affected the removal efficiency were systematically investigated, which allowed us to determine optimal operation parameters. With this new method we found that the removal efficiency was significantly improved from 66.7% by adsorption only to 95% by adsorption-DEP using titanium metal mesh as electrodes of the DEP and zeolite as the absorbent material. In addition, the dosage of the absorbent/zeolite and the processing time needed for the removal were greatly reduced after the introduction of DEP into the process. In addition, a very low discharge concentration (C, 1.5 mg/L) of NH 3 -N was achieved by the new method, which well met the discharge criterion of C < 8 mg/L (the emission standard of pollutants for rare earth industry in China).

Fundamental and future prospects of printed ambipolar fluorene-type polymer light-emitting transistors for improved external quantum efficiency, mobility, and emission pattern

NASA Astrophysics Data System (ADS)

Kajii, Hirotake

2018-05-01

In this review, we focus on the improved external quantum efficiency, field-effect mobility, and emission pattern of top-gate-type polymer light-emitting transistors (PLETs) based on ambipolar fluorene-type polymers. A low-temperature, high-efficiency, printable red phosphorescent PLET based on poly(alkylfluorene) with modified alkyl side chains fabricated by a film transfer process is demonstrated. Device fabrication based on oriented films leads to an improved EL intensity owing to the increase in field-effect mobility. There are three factors that affect the transport of carriers, i.e., the energy level, threshold voltage, and mobility of each layer for heterostructure PLETs, which result in various emission patterns such as the line-shaped, multicolor and in-plane emission pattern in the full-channel area between source and drain electrodes. Fundamentals and future prospects in heterostructure devices are discussed and reviewed.

Energy distribution analysis in boosted HCCI-like / LTGC engines – Understanding the trade-offs to maximize the thermal efficiency

DOE PAGES

Dernotte, Jeremie; Dec, John E.; Ji, Chunsheng

2015-04-14

A detailed understanding of the various factors affecting the trends in gross-indicated thermal efficiency with changes in key operating parameters has been carried out, applied to a one-liter displacement single-cylinder boosted Low-Temperature Gasoline Combustion (LTGC) engine. This work systematically investigates how the supplied fuel energy splits into the following four energy pathways: gross-indicated thermal efficiency, combustion inefficiency, heat transfer and exhaust losses, and how this split changes with operating conditions. Additional analysis is performed to determine the influence of variations in the ratio of specific heat capacities (γ) and the effective expansion ratio, related to the combustion-phasing retard (CA50), onmore » the energy split. Heat transfer and exhaust losses are computed using multiple standard cycle analysis techniques. Furthermore, the various methods are evaluated in order to validate the trends.« less

Reducing the impact of speed dispersion on subway corridor flow.

PubMed

Qiao, Jing; Sun, Lishan; Liu, Xiaoming; Rong, Jian

2017-11-01

The rapid increase in the volume of subway passengers in Beijing has necessitated higher requirements for the safety and efficiency of subway corridors. Speed dispersion is an important factor that affects safety and efficiency. This paper aims to analyze the management control methods for reducing pedestrian speed dispersion in subways. The characteristics of the speed dispersion of pedestrian flow were analyzed according to field videos. The control measurements which were conducted by placing traffic signs, yellow marking, and guardrail were proposed to alleviate speed dispersion. The results showed that the methods of placing traffic signs, yellow marking, and a guardrail improved safety and efficiency for all four volumes of pedestrian traffic flow, and the best-performing control measurement was guardrails. Furthermore, guardrails' optimal position and design measurements were explored. The research findings provide a rationale for subway managers in optimizing pedestrian traffic flow in subway corridors. Copyright © 2017. Published by Elsevier Ltd.

Nanolipodendrosome-loaded glatiramer acetate and myogenic differentiation 1 as augmentation therapeutic strategy approaches in muscular dystrophy.

PubMed

Afzal, Ehsan; Zakeri, Saba; Keyhanvar, Peyman; Bagheri, Meisam; Mahjoubi, Parvin; Asadian, Mahtab; Omoomi, Nogol; Dehqanian, Mohammad; Ghalandarlaki, Negar; Darvishmohammadi, Tahmineh; Farjadian, Fatemeh; Golvajoee, Mohammad Sadegh; Afzal, Shadi; Ghaffari, Maryam; Cohan, Reza Ahangari; Gravand, Amin; Ardestani, Mehdi Shafiee

2013-01-01

[Corrected] Muscular dystrophies consist of a number of juvenile and adult forms of complex disorders which generally cause weakness or efficiency defects affecting skeletal muscles or, in some kinds, other types of tissues in all parts of the body are vastly affected. In previous studies, it was observed that along with muscular dystrophy, immune inflammation was caused by inflammatory cells invasion - like T lymphocyte markers (CD8+/CD4+). Inflammatory processes play a major part in muscular fibrosis in muscular dystrophy patients. Additionally, a significant decrease in amounts of two myogenic recovery factors (myogenic differentation 1 [MyoD] and myogenin) in animal models was observed. The drug glatiramer acetate causes anti-inflammatory cytokines to increase and T helper (Th) cells to induce, in an as yet unknown mechanism. MyoD recovery activity in muscular cells justifies using it alongside this drug. In this study, a nanolipodendrosome carrier as a drug delivery system was designed. The purpose of the system was to maximize the delivery and efficiency of the two drug factors, MyoD and myogenin, and introduce them as novel therapeutic agents in muscular dystrophy phenotypic mice. The generation of new muscular cells was analyzed in SW1 mice. Then, immune system changes and probable side effects after injecting the nanodrug formulations were investigated. The loaded lipodendrimer nanocarrier with the candidate drug, in comparison with the nandrolone control drug, caused a significant increase in muscular mass, a reduction in CD4+/CD8+ inflammation markers, and no significant toxicity was observed. The results support the hypothesis that the nanolipodendrimer containing the two candidate drugs will probably be an efficient means to ameliorate muscular degeneration, and warrants further investigation.

Nanolipodendrosome-loaded glatiramer acetate and myogenic differentiation 1 as augmentation therapeutic strategy approaches in muscular dystrophy

PubMed Central

Afzal, Ehsan; Zakeri, Saba; Keyhanvar, Peyman; Bagheri, Meisam; Mahjoubi, Parvin; Asadian, Mahtab; Omoomi, Nogol; Dehqanian, Mohammad; Ghalandarlaki, Negar; Darvishmohammadi, Tahmineh; Farjadian, Fatemeh; Golvajoee, Mohammad Sadegh; Afzal, Shadi; Ghaffari, Maryam; Cohan, Reza Ahangari; Gravand, Amin; Ardestani, Mehdi Shafiee

2013-01-01

Backgrond Muscular dystrophies consist of a number of juvenile and adult forms of complex disorders which generally cause weakness or efficiency defects affecting skeletal muscles or, in some kinds, other types of tissues in all parts of the body are vastly affected. In previous studies, it was observed that along with muscular dystrophy, immune inflammation was caused by inflammatory cells invasion – like T lymphocyte markers (CD8+/CD4+). Inflammatory processes play a major part in muscular fibrosis in muscular dystrophy patients. Additionally, a significant decrease in amounts of two myogenic recovery factors (myogenic differentation 1 [MyoD] and myogenin) in animal models was observed. The drug glatiramer acetate causes anti-inflammatory cytokines to increase and T helper (Th) cells to induce, in an as yet unknown mechanism. MyoD recovery activity in muscular cells justifies using it alongside this drug. Methods In this study, a nanolipodendrosome carrier as a drug delivery system was designed. The purpose of the system was to maximize the delivery and efficiency of the two drug factors, MyoD and myogenin, and introduce them as novel therapeutic agents in muscular dystrophy phenotypic mice. The generation of new muscular cells was analyzed in SW1 mice. Then, immune system changes and probable side effects after injecting the nanodrug formulations were investigated. Results The loaded lipodendrimer nanocarrier with the candidate drug, in comparison with the nandrolone control drug, caused a significant increase in muscular mass, a reduction in CD4+/CD8+ inflammation markers, and no significant toxicity was observed. The results support the hypothesis that the nanolipodendrimer containing the two candidate drugs will probably be an efficient means to ameliorate muscular degeneration, and warrants further investigation. PMID:23966782

An economic evaluation and assessment of environmental impact of the municipal solid waste management system for Taichung City in Taiwan.

PubMed

Chang, Yao-Jen; Chu, Chien-Wei; Lin, Min-Der

2012-05-01

Municipal solid waste management (MSWM) is an important environmental challenge and subject in urban planning. For sustainable MSWM strategies, the critical management factors to be considered include not only economic efficiency of MSW treatment but also life-cycle assessment of the environmental impact. This paper employed linear programming technique to establish optimal MSWM strategies considering economic efficiency and the air pollutant emissions during the life cycle of a MSWM system, and investigated the correlations between the economical optimization and pollutant emissions. A case study based on real-world MSW operating parameters in Taichung City is also presented. The results showed that the costs, benefits, streams of MSW, and throughputs of incinerators and landfills will be affected if pollution emission reductions are implemented in the MSWM strategies. In addition, the quantity of particulate matter is the best pollutant indicator for the MSWM system performance of emission reduction. In particular this model will assist the decision maker in drawing up a friendly MSWM strategy for Taichung City in Taiwan. Recently, life-cycle assessments of municipal solid waste management (MSWM) strategies have been given more considerations. However, what seems to be lacking is the consideration of economic factors and environmental impacts simultaneously. This work analyzed real-world data to establish optimal MSWM strategies considering economic efficiency and the air pollutant emissions during the life cycle of the MSWM system. The results indicated that the consideration of environmental impacts will affect the costs, benefits, streams of MSW, and throughputs of incinerators and landfills. This work is relevant to public discussion and may establish useful guidelines for the MSWM policies.

Spatial Characteristics and Driving Factors of Provincial Wastewater Discharge in China

PubMed Central

Chen, Kunlun; Liu, Xiaoqiong; Ding, Lei; Huang, Gengzhi; Li, Zhigang

2016-01-01

Based on the increasing pressure on the water environment, this study aims to clarify the overall status of wastewater discharge in China, including the spatio-temporal distribution characteristics of wastewater discharge and its driving factors, so as to provide reference for developing “emission reduction” strategies in China and discuss regional sustainable development and resources environment policies. We utilized the Exploratory Spatial Data Analysis (ESDA) method to analyze the characteristics of the spatio-temporal distribution of the total wastewater discharge among 31 provinces in China from 2002 to 2013. Then, we discussed about the driving factors, affected the wastewater discharge through the Logarithmic Mean Divisia Index (LMDI) method and classified those driving factors. Results indicate that: (1) the total wastewater discharge steadily increased, based on the social economic development, with an average growth rate of 5.3% per year; the domestic wastewater discharge is the main source of total wastewater discharge, and the amount of domestic wastewater discharge is larger than the industrial wastewater discharge. There are many spatial differences of wastewater discharge among provinces via the ESDA method. For example, provinces with high wastewater discharge are mainly the developed coastal provinces such as Jiangsu Province and Guangdong Province. Provinces and their surrounding areas with low wastewater discharge are mainly the undeveloped ones in Northwest China; (2) The dominant factors affecting wastewater discharge are the economy and technological advance; The secondary one is the efficiency of resource utilization, which brings about the unstable effect; population plays a less important role in wastewater discharge. The dominant driving factors affecting wastewater discharge among 31 provinces are divided into three types, including two-factor dominant type, three-factor leading type and four-factor antagonistic type. In addition, the proposals aimed at reducing the wastewater discharge are provided on the basis of these three types. PMID:27941698

Effects of temperature on the removal efficiency of KDP crystal during the process of magnetorheological water-dissolution polishing.

PubMed

Zhang, Yifan; Dai, Yifan; Tie, Guipeng; Hu, Hao

2016-10-10

As a kind of important nonlinear optical element, KDP crystal has great demand in the inertial confinement fusion system. Based on the dissolution mechanism of solid materials, the factors that affect the material removal rate of KDP crystal in magnetorheological (MR) water-dissolution polishing are investigated to improve the machining efficiency. It is found that the material removal rate is proportional to the product of the saturation concentration and diffusion coefficient, and the relationship between the removal efficiency and the temperature meets the unilateral Gaussian function. Polishing experiments are carried out on a magnetorheological finishing (MRF) machine with self-designed MRF fluid heating devices. The experimental results show that practical efficiency-temperature curve is consistent with the theoretical curve, and the maximum machining efficiency increases by about 50% with the rise of temperature from 294 to 302 K. Meanwhile, when the MR fluid temperature is lower than 308 K, the crystal surface quality and surface roughness in different processing temperatures have no remarkable difference with constant crystal temperature (294 K). This research indicates that it is feasible to drastically improve KDP crystal MRF efficiency by controlling the processing temperature.

Femtosecond laser for cavity preparation in enamel and dentin: ablation efficiency related factors.

PubMed

Chen, H; Li, H; Sun, Yc; Wang, Y; Lü, Pj

2016-02-11

To study the effects of laser fluence (laser energy density), scanning line spacing and ablation depth on the efficiency of a femtosecond laser for three-dimensional ablation of enamel and dentin. A diode-pumped, thin-disk femtosecond laser (wavelength 1025 nm, pulse width 400 fs) was used for the ablation of enamel and dentin. The laser spot was guided in a series of overlapping parallel lines on enamel and dentin surfaces to form a three-dimensional cavity. The depth and volume of the ablated cavity was then measured under a 3D measurement microscope to determine the ablation efficiency. Different values of fluence, scanning line spacing and ablation depth were used to assess the effects of each variable on ablation efficiency. Ablation efficiencies for enamel and dentin were maximized at different laser fluences and number of scanning lines and decreased with increases in laser fluence or with increases in scanning line spacing beyond spot diameter or with increases in ablation depth. Laser fluence, scanning line spacing and ablation depth all significantly affected femtosecond laser ablation efficiency. Use of a reasonable control for each of these parameters will improve future clinical application.

Impact of Mycobacterium avium subspecies paratuberculosis on profit efficiency in semi-extensive dairy sheep and goat farms of Apulia, southern Italy.

PubMed

Sardaro, Ruggiero; Pieragostini, Elisa; Rubino, Giuseppe; Petazzi, Ferruccio

2017-01-01

A recent study on paratubercolosis in semi-extensive dairy sheep and goat farms in Apulia revealed a flock positivity of 60.5% and a seroprevalence of 3.0% for sheep and 14.5% for goat, with peaks of 50%. In such a context, providing detailed economic information is crucial for the implementation of a suitable control plan. In this paper we investigated the impact of Mycobacterium avium subspecies paratuberculosis (MAP) on profit efficiency of the Apulian dairy sheep and goat farms. Empirical results through a stochastic frontier model showed that the uninfected farms had a mean level of profit efficiency of 84%, which dropped to 64% in the presence of paratubercolosis as it negatively affected the productivity of feeding, veterinary and labour factors. Structural, managerial and production aspects were involved in the greater inefficiency of the infected farms compared to the uninfected ones: lower experience and schooling of farmers, no access to credit, fewer family members (women in particular) participating in the farming activities, high density of animals per hectare, small flocks, high number of goats in mixed flocks, no confinement practices for young and purchased animals and no pasture rotation. Hence, targeted interventions on these factors by decision makers can ensure effectiveness and efficiency to veterinary and economic action plans. Copyright © 2016 Elsevier B.V. All rights reserved.

A dual selection based, targeted gene replacement tool for Magnaporthe grisea and Fusarium oxysporum.

PubMed

Khang, Chang Hyun; Park, Sook-Young; Lee, Yong-Hwan; Kang, Seogchan

2005-06-01

Rapid progress in fungal genome sequencing presents many new opportunities for functional genomic analysis of fungal biology through the systematic mutagenesis of the genes identified through sequencing. However, the lack of efficient tools for targeted gene replacement is a limiting factor for fungal functional genomics, as it often necessitates the screening of a large number of transformants to identify the desired mutant. We developed an efficient method of gene replacement and evaluated factors affecting the efficiency of this method using two plant pathogenic fungi, Magnaporthe grisea and Fusarium oxysporum. This method is based on Agrobacterium tumefaciens-mediated transformation with a mutant allele of the target gene flanked by the herpes simplex virus thymidine kinase (HSVtk) gene as a conditional negative selection marker against ectopic transformants. The HSVtk gene product converts 5-fluoro-2'-deoxyuridine to a compound toxic to diverse fungi. Because ectopic transformants express HSVtk, while gene replacement mutants lack HSVtk, growing transformants on a medium amended with 5-fluoro-2'-deoxyuridine facilitates the identification of targeted mutants by counter-selecting against ectopic transformants. In addition to M. grisea and F. oxysporum, the method and associated vectors are likely to be applicable to manipulating genes in a broad spectrum of fungi, thus potentially serving as an efficient, universal functional genomic tool for harnessing the growing body of fungal genome sequence data to study fungal biology.

Nonnegative Matrix Factorization for Efficient Hyperspectral Image Projection

NASA Technical Reports Server (NTRS)

Iacchetta, Alexander S.; Fienup, James R.; Leisawitz, David T.; Bolcar, Matthew R.

2015-01-01

Hyperspectral imaging for remote sensing has prompted development of hyperspectral image projectors that can be used to characterize hyperspectral imaging cameras and techniques in the lab. One such emerging astronomical hyperspectral imaging technique is wide-field double-Fourier interferometry. NASA's current, state-of-the-art, Wide-field Imaging Interferometry Testbed (WIIT) uses a Calibrated Hyperspectral Image Projector (CHIP) to generate test scenes and provide a more complete understanding of wide-field double-Fourier interferometry. Given enough time, the CHIP is capable of projecting scenes with astronomically realistic spatial and spectral complexity. However, this would require a very lengthy data collection process. For accurate but time-efficient projection of complicated hyperspectral images with the CHIP, the field must be decomposed both spectrally and spatially in a way that provides a favorable trade-off between accurately projecting the hyperspectral image and the time required for data collection. We apply nonnegative matrix factorization (NMF) to decompose hyperspectral astronomical datacubes into eigenspectra and eigenimages that allow time-efficient projection with the CHIP. Included is a brief analysis of NMF parameters that affect accuracy, including the number of eigenspectra and eigenimages used to approximate the hyperspectral image to be projected. For the chosen field, the normalized mean squared synthesis error is under 0.01 with just 8 eigenspectra. NMF of hyperspectral astronomical fields better utilizes the CHIP's capabilities, providing time-efficient and accurate representations of astronomical scenes to be imaged with the WIIT.

Influence of item distribution pattern and abundance on efficiency of benthic core sampling

USGS Publications Warehouse

Behney, Adam C.; O'Shaughnessy, Ryan; Eichholz, Michael W.; Stafford, Joshua D.

2014-01-01

ore sampling is a commonly used method to estimate benthic item density, but little information exists about factors influencing the accuracy and time-efficiency of this method. We simulated core sampling in a Geographic Information System framework by generating points (benthic items) and polygons (core samplers) to assess how sample size (number of core samples), core sampler size (cm2), distribution of benthic items, and item density affected the bias and precision of estimates of density, the detection probability of items, and the time-costs. When items were distributed randomly versus clumped, bias decreased and precision increased with increasing sample size and increased slightly with increasing core sampler size. Bias and precision were only affected by benthic item density at very low values (500–1,000 items/m2). Detection probability (the probability of capturing ≥ 1 item in a core sample if it is available for sampling) was substantially greater when items were distributed randomly as opposed to clumped. Taking more small diameter core samples was always more time-efficient than taking fewer large diameter samples. We are unable to present a single, optimal sample size, but provide information for researchers and managers to derive optimal sample sizes dependent on their research goals and environmental conditions.

Analyses of mode filling factor of a laser end-pumped by a LD with high-order transverse modes

NASA Astrophysics Data System (ADS)

Han, Juhong; Wang, You; An, Guofei; Rong, Kepeng; Yu, Hang; Wang, Shunyan; Zhang, Wei; Cai, He; Xue, Liangping; Wang, Hongyuan; Zhou, Jie

2017-05-01

Although the concept of the mode filling factor (also named as "mode-matching efficiency") has been well discussed decades before, the concept of so-called overlap coefficient is often confused by the laser technicians because there are several different formulae for various engineering purposes. Furthermore, the LD-pumped configurations have become the mainstream of solid-state lasers since their compact size, high optical-to-optical efficiency, low heat generation, etc. As the beam quality of LDs are usually very unsatisfactory, it is necessary to investigate how the mode filling factor of a laser system is affected by a high-powered LD pump source. In this paper, theoretical analyses of an end-pumped laser are carried out based on the normalized overlap coefficient formalism. The study provides a convenient tool to describe the intrinsically complex issue of mode interaction corresponding to a laser and an end-pumped source. The mode filling factor has been studied for many cases in which the pump mode and the laser mode have been considered together in the calculation based on analyses of the rate equations. The results should be applied for analyses of any other types of lasers with the similar optical geometry.

Efficient computation of turbulent flow in ribbed passages using a non-overlapping near-wall domain decomposition method

NASA Astrophysics Data System (ADS)

Jones, Adam; Utyuzhnikov, Sergey

2017-08-01

Turbulent flow in a ribbed channel is studied using an efficient near-wall domain decomposition (NDD) method. The NDD approach is formulated by splitting the computational domain into an inner and outer region, with an interface boundary between the two. The computational mesh covers the outer region, and the flow in this region is solved using the open-source CFD code Code_Saturne with special boundary conditions on the interface boundary, called interface boundary conditions (IBCs). The IBCs are of Robin type and incorporate the effect of the inner region on the flow in the outer region. IBCs are formulated in terms of the distance from the interface boundary to the wall in the inner region. It is demonstrated that up to 90% of the region between the ribs in the ribbed passage can be removed from the computational mesh with an error on the friction factor within 2.5%. In addition, computations with NDD are faster than computations based on low Reynolds number (LRN) models by a factor of five. Different rib heights can be studied with the same mesh in the outer region without affecting the accuracy of the friction factor. This is tested with six different rib heights in an example of a design optimisation study. It is found that the friction factors computed with NDD are almost identical to the fully-resolved results. When used for inverse problems, NDD is considerably more efficient than LRN computations because only one computation needs to be performed and only one mesh needs to be generated.

Neuromuscular factors associated with decline in long-distance running performance in master athletes.

PubMed

Brisswalter, Jeanick; Nosaka, Kazunori

2013-01-01

This review focuses on neuromuscular factors that may affect endurance performance in master athletes. During the last decade, due to the rapid increase in the number of master or veteran participants in endurance sporting competitions, many studies attempted to identify metabolic factors associated with the decrease in endurance, especially long-distance running performance with ageing, focusing on decreases in maximal oxygen consumption. However, neuromuscular factors have been less studied despite the well-known phenomena of strength loss with ageing. For master athletes to perform better in long-distance running events, it is important to reduce muscle fatigue and/or muscle damage, to improve locomotion efficiency and to facilitate recovery. To date, no consensus exists that regular endurance training is beneficial for improving locomotion efficiency, reducing muscle fatigue and muscle damage, and enhancing recovery capacity in master athletes. Some recent studies seem to indicate that master athletes have similar muscle damage to young athletes, but they require a longer recovery time after a long-distance running event. Further analyses of these parameters in master athletes require more experimental and practical interest from researchers and coaches. In particular, more attention should be directed towards the capacity to maintain muscle function with training and the role of neuromuscular factors in long-distance performance decline with ageing using a more cellular and molecular approach.

Vortex-assisted magnetic β-cyclodextrin/attapulgite-linked ionic liquid dispersive liquid-liquid microextraction coupled with high-performance liquid chromatography for the fast determination of four fungicides in water samples.

PubMed

Yang, Miyi; Xi, Xuefei; Wu, Xiaoling; Lu, Runhua; Zhou, Wenfeng; Zhang, Sanbing; Gao, Haixiang

2015-02-13

A novel microextraction technique combining magnetic solid-phase microextraction (MSPME) with ionic liquid dispersive liquid-liquid microextraction (IL-DLLME) to determine four fungicides is presented in this work for the first time. The main factors affecting the extraction efficiency were optimized by the one-factor-at-a-time approach and the impacts of these factors were studied by an orthogonal design. Without tedious clean-up procedure, analytes were extracted from the sample to the adsorbent and organic solvent and then desorbed in acetonitrile prior to chromatographic analysis. Under the optimum conditions, good linearity and high enrichment factors were obtained for all analytes, with correlation coefficients ranging from 0.9998 to 1.0000 and enrichment factors ranging 135 and 159 folds. The recoveries for proposed approach were between 98% and 115%, the limits of detection were between 0.02 and 0.04 μg L(-1) and the RSDs changed from 2.96 to 4.16. The method was successfully applied in the analysis of four fungicides (azoxystrobin, chlorothalonil, cyprodinil and trifloxystrobin) in environmental water samples. The recoveries for the real water samples ranged between 81% and 109%. The procedure proved to be a time-saving, environmentally friendly, and efficient analytical technique. Copyright © 2015 Elsevier B.V. All rights reserved.

New Insights into the Instability of Discharge Products in Na-O2 Batteries.

PubMed

Landa-Medrano, Imanol; Pinedo, Ricardo; Bi, Xuanxuan; Ruiz de Larramendi, Idoia; Lezama, Luis; Janek, Jürgen; Amine, Khalil; Lu, Jun; Rojo, Teófilo

2016-08-10

Sodium-oxygen batteries currently stimulate extensive research due to their high theoretical energy density and improved operational stability when compared to lithium-oxygen batteries. Cell stability, however, needs to be demonstrated also under resting conditions before future implementation of these batteries. In this work we analyze the effect of resting periods on the stability of the sodium superoxide (NaO2) discharge product. The instability of NaO2 in the cell environment is demonstrated leading to the evolution of oxygen during the resting period and the decrease of the cell efficiency. In addition, migration of the superoxide anion (O2(-)) in the electrolyte is observed and demonstrated to be an important factor affecting Coulombic efficiency.

New Insights into the Instability of Discharge Products in Na–O 2 Batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Landa-Medrano, Imanol; Pinedo, Ricardo; Bi, Xuanxuan

2016-08-10

Sodium–oxygen batteries currently stimulate extensive research due to their high theoretical energy density and improved operational stability when compared to lithium–oxygen batteries. Cell stability, however, needs to be demonstrated also under resting conditions before future implementation of these batteries. In this work we analyze the effect of resting periods on the stability of the sodium superoxide (NaO 2) discharge product. The instability of NaO 2 in the cell environment is demonstrated leading to the evolution of oxygen during the resting period and the decrease of the cell efficiency. In addition, migration of the superoxide anion (O2–) in the electrolyte ismore » observed and demonstrated to be an important factor affecting Coulombic efficiency.« less

Light engineering for bifacial transparent perovskite solar cells with high performance

NASA Astrophysics Data System (ADS)

Gao, Liguo; Zhao, Erling; Yang, Shuzhang; Wang, Likun; Li, Yanqiang; Zhao, Yingyuan; Ma, Tingli

2017-11-01

Bifacial transparent perovskite solar cells (BTPSCs) were designed to harvest more solar energy and ensure higher efficiency than conventional PSCs. A series of BTPSCs was successfully prepared using transparent ultrathin Au electrodes with different thicknesses. The transmittance and resistance of Au electrodes played a major role in achieving photo-to-electricity conversion efficiency (PCE). Engineering the light-harvesting ability of the fabricated BTPSCs led to the highest PCE of 14.74%. Reflecting-light intensity and illumination angle were further observed to be the key factors affecting PCE. These BTPSCs could be applied on building integration of photovoltaics (PVs), such as semitransparent PV windows or venetian blinds. Another alternative application is to use these BTPSCs as the wings of unmanned aerial vehicles.

High Efficiency InP Solar Cells from Low Toxicity Tertiarybutylphosphine

NASA Technical Reports Server (NTRS)

Hoffman, Richard W., Jr.; Fatemi, Navid S.; Wilt, David M.; Jenkins, Phillip P.; Brinker, David J.; Scheiman, David A.

1994-01-01

Large scale manufacture of phosphide based semiconductor devices by organo-metallic vapor phase epitaxy (OMVPE) typically requires the use of highly toxic phosphine. Advancements in phosphine substitutes have identified tertiarybutylphosphine (TBP) as an excellent precursor for OMVPE of InP. High quality undoped and doped InP films were grown using TBP and trimethylindium. Impurity doped InP films were achieved utilizing diethylzinc and silane for p and n type respectively. 16 percent efficient solar cells under air mass zero, one sun intensity were demonstrated with Voc of 871 mV and fill factor of 82.6 percent. It was shown that TBP could replace phosphine, without adversely affecting device quality, in OMVPE deposition of InP thus significantly reducing toxic gas exposure risk.

The effect of nano-silica fertilizer concentration and rice hull ash doses on soybean (Glycine max (L.) Merrill) growth and yield

NASA Astrophysics Data System (ADS)

Suciaty, T.; Purnomo, D.; Sakya, A. T.; Supriyadi

2018-03-01

Agriculture is facing a number of challenges included limited water supply, low nutrient use efficiency, etc affected by climate change. Nano-silica is a product of nanotechnology, the frontier technologies to enhance crop productivity under climate change threats. The purpose of the research was to investigate the effects of nano silica concentration and rice hull ash on growth and yield of soybean. The experiment was conducted at Gagasari village, Cirebon, West Java from March until June 2017. The treatments were arranged by using factorial completely randomized block design with two factors. The first factor was a concentration of nano silica fertilizer consisted of four levels i.e., 0, 1.75, 2.5, and 3.75 ml.l‑1. The second factor was doses of rice hull ash consisted of four levels i.e., 0, 1, 2, and 3 ton.ha‑1. Each treatment combinations was repeated three times. The result showed that concentration of nano silica individually affected the number of leaves and number of branches, NAR and RGR, productive branches at 21, 30-45, and 35 daps, respectively. It also affected the seed dry weight plant‑1 and plot‑1. Meanwhile, doses of rice hull ash affected LAI, NAR, and RGR, 15-30, and 30-45 dap, respectively. Dry seed weight plot‑1 was also affected by doses of rice hull ash. There was an interaction effect between nano-silica concentration and doses of rice hull ash on number pods.plant‑1. Combinations of 2.5 ml.l‑1 nano-silica and 3 ton.ha‑1 of rice hull ash gave the highest number pods.plant‑1.

Tyrosine-phosphorylation of AAV2 vectors and its consequences on viral intracellular trafficking and transgene expression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhong Li; Powell Gene Therapy Center, University of Florida College of Medicine, Gainesville, FL; Genetics Institute, University of Florida College of Medicine, Gainesville, FL

2008-11-25

We have documented that epidermal growth factor receptor protein tyrosine kinase (EGFR-PTK) signaling negatively affects intracellular trafficking and transduction efficiency of recombinant adeno-associated virus 2 (AAV2) vectors. Specifically, inhibition of EGFR-PTK signaling leads to decreased ubiquitination of AAV2 capsid proteins, which in turn, facilitates viral nuclear transport by limiting proteasome-mediated degradation of AAV2 vectors. In the present studies, we observed that AAV capsids can indeed be phosphorylated at tyrosine residues by EGFR-PTK in in vitro phosphorylation assays and that phosphorylated AAV capsids retain their structural integrity. However, although phosphorylated AAV vectors enter cells as efficiently as their unphosphorylated counterparts, theirmore » transduction efficiency is significantly reduced. This reduction is not due to impaired viral second-strand DNA synthesis since transduction efficiency of both single-stranded AAV (ssAAV) and self-complementary AAV (scAAV) vectors is decreased by {approx} 68% and {approx} 74%, respectively. We also observed that intracellular trafficking of tyrosine-phosphorylated AAV vectors from cytoplasm to nucleus is significantly decreased, which results from ubiquitination of AAV capsids followed by proteasome-mediated degradation, although downstream consequences of capsid ubiquitination may also be affected by tyrosine-phosphorylation. These studies provide new insights into the role of tyrosine-phosphorylation of AAV capsids in various steps in the virus life cycle, which has implications in the optimal use of recombinant AAV vectors in human gene therapy.« less

Efficiency of urease and nitrification inhibitors in reducing ammonia volatilization from diverse nitrogen fertilizers applied to different soil types and wheat straw mulching.

PubMed

San Francisco, Sara; Urrutia, Oscar; Martin, Vincent; Peristeropoulos, Angelos; Garcia-Mina, Jose Maria

2011-07-01

Some authors suggest that the absence of tillage in agricultural soils might have an influence on the efficiency of nitrogen applied in the soil surface. In this study we investigate the influence of no-tillage and soil characteristics on the efficiency of a urease inhibitor (N-(n-butyl)thiophosphoric triamide, NBPT) and a nitrification inhibitor (diciandiamide, DCD) in decreasing ammonia volatilization from urea and ammonium nitrate (AN), respectively. The results indicate that ammonia volatilization in soils amended with urea was significantly higher than in those fertilized with AN. Likewise, the main soil factors affecting ammonia volatilization from urea are clay and sand soil contents. While clay impedes ammonia volatilization, sand favours it. The presence of organic residues on soil surface (no-tillage) tends to increase ammonia volatilization from urea, although this fact depended on soil type. The presence of NBPT in urea fertilizer significantly reduced soil ammonia volatilization. This action of NBPT was negatively affected by acid soil pH and favoured by soil clay content. The presence of organic residues on soil surface amended with urea increased ammonia volatilization, and was particularly high in sandy compared with clay soils. Application of NBPT reduced ammonia volatilization although its efficiency is reduced in acid soils. Concerning AN fertilization, there were no differences in ammonia volatilization with or without DCD in no-tillage soils. Copyright © 2011 Society of Chemical Industry.

Water demand management in times of drought: What matters for water conservation

NASA Astrophysics Data System (ADS)

Maggioni, Elena

2015-01-01

Southern California is subject to long droughts and short wet spells. Its water agencies have put in place voluntary, mandatory, and market-based conservation strategies since the 1980s. By analyzing water agencies' data between 2006 and 2010, this research studies whether rebates for water efficient fixtures, water rates, or water ordinances have been effective, and tests whether structural characteristics of water agencies have affected the policy outcome. It finds that mandates to curb outdoor water uses are correlated with reductions in residential per capita water usage, while water rates and subsidies for water saving devices are not. It also confirms that size is a significant policy implementation factor. In a policy perspective, the transition from a water supply to a water demand management-oriented strategy appears guided by mandates and by contextual factors such as the economic cycle and the weather that occur outside the water governance system. Three factors could improve the conservation effort: using prices as a conservation tool, not only as a cost recovering instrument; investing in water efficient tools only when they provide significant water savings; supporting smaller agencies in order to give them opportunities to implement conservation strategies more effectively or to help them consolidate.

Antimicrobial Nanoplexes meet Model Bacterial Membranes: the key role of Cardiolipin

NASA Astrophysics Data System (ADS)

Marín-Menéndez, Alejandro; Montis, Costanza; Díaz-Calvo, Teresa; Carta, Davide; Hatzixanthis, Kostas; Morris, Christopher J.; McArthur, Michael; Berti, Debora

2017-01-01

Antimicrobial resistance to traditional antibiotics is a crucial challenge of medical research. Oligonucleotide therapeutics, such as antisense or Transcription Factor Decoys (TFDs), have the potential to circumvent current resistance mechanisms by acting on novel targets. However, their full translation into clinical application requires efficient delivery strategies and fundamental comprehension of their interaction with target bacterial cells. To address these points, we employed a novel cationic bolaamphiphile that binds TFDs with high affinity to form self-assembled complexes (nanoplexes). Confocal microscopy revealed that nanoplexes efficiently transfect bacterial cells, consistently with biological efficacy on animal models. To understand the factors affecting the delivery process, liposomes with varying compositions, taken as model synthetic bilayers, were challenged with nanoplexes and investigated with Scattering and Fluorescence techniques. Thanks to the combination of results on bacteria and synthetic membrane models we demonstrate for the first time that the prokaryotic-enriched anionic lipid Cardiolipin (CL) plays a key-role in the TFDs delivery to bacteria. Moreover, we can hypothesize an overall TFD delivery mechanism, where bacterial membrane reorganization with permeability increase and release of the TFD from the nanoplexes are the main factors. These results will be of great benefit to boost the development of oligonucleotides-based antimicrobials of superior efficacy.

The effect of fatigue driving on injury severity considering the endogeneity.

PubMed

Li, Yanyan; Yamamoto, Toshiyuki; Zhang, Guangnan

2018-02-01

Fatigue driving is one of the most risky driving-related behaviors and represented a significant social and economic cost to the community. Several studies have already examined the relationship between fatigue driving behavior and traffic injury severity from different aspects. However, fatigue driving and injury severity in traffic crash may share some common influential factors. Ignoring the impact of these common factors will lead to endogeneity problem and result in biased parameter estimation. Based on 38,564 crash records during 2006-2011 in Guangdong province, China, we apply a bivariate endogenous binary-ordered probit model to examine the relationship between fatigue driving and injury severity considering endogeneity of fatigue driving. We also explore the difference of influential factors between commercial and non-commercial vehicle drivers. This study identifies several common observed influential factors of fatigue driving propensity and fatal injury propensity and reveals a substantial and significant negative correlation of unobserved factors between them. The influence of fatigue driving on injury severity is significantly underestimated if the endogeneity of fatigue driving on fatal injury propensity is ignored. Factors such as vehicle insurance and road types not only affect fatal injury propensity, but also fatigue driving propensity. The findings in this study can help better understand how those factors affect fatigue driving and injury severity, and contributes to more efficient policy for preventing the harmfulness of fatigue-related crashes. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

Impact of Indoor Physical Environment on Learning Efficiency in Different Types of Tasks: A 3 × 4 × 3 Full Factorial Design Analysis.

PubMed

Xiong, Lilin; Huang, Xiao; Li, Jie; Mao, Peng; Wang, Xiang; Wang, Rubing; Tang, Meng

2018-06-13

Indoor physical environments appear to influence learning efficiency nowadays. For improvement in learning efficiency, environmental scenarios need to be designed when occupants engage in different learning tasks. However, how learning efficiency is affected by indoor physical environment based on task types are still not well understood. The present study aims to explore the impacts of three physical environmental factors (i.e., temperature, noise, and illuminance) on learning efficiency according to different types of tasks, including perception, memory, problem-solving, and attention-oriented tasks. A 3 × 4 × 3 full factorial design experiment was employed in a university classroom with 10 subjects recruited. Environmental scenarios were generated based on different levels of temperature (17 °C, 22 °C, and 27 °C), noise (40 dB(A), 50 dB(A), 60 dB(A), and 70 dB(A)) and illuminance (60 lx, 300 lx, and 2200 lx). Accuracy rate (AC), reaction time (RT), and the final performance indicator (PI) were used to quantify learning efficiency. The results showed ambient temperature, noise, and illuminance exerted significant main effect on learning efficiency based on four task types. Significant concurrent effects of the three factors on final learning efficiency was found in all tasks except problem-solving-oriented task. The optimal environmental scenarios for top learning efficiency were further identified under different environmental interactions. The highest learning efficiency came in thermoneutral, relatively quiet, and bright conditions in perception-oriented task. Subjects performed best under warm, relatively quiet, and moderately light exposure when recalling images in the memory-oriented task. Learning efficiency peaked to maxima in thermoneutral, fairly quiet, and moderately light environment in problem-solving process while in cool, fairly quiet and bright environment with regard to attention-oriented task. The study provides guidance for building users to conduct effective environmental intervention with simultaneous controls of ambient temperature, noise, and illuminance. It contributes to creating the most suitable indoor physical environment for improving occupants learning efficiency according to different task types. The findings could further supplement the present indoor environment-related standards or norms with providing empirical reference on environmental interactions.

A Sensitivity Study on Modeling Black Carbon in Snow and its Radiative Forcing over the Arctic and Northern China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qian, Yun; Wang, Hailong; Zhang, Rudong

2014-06-02

Black carbon in snow (BCS) simulated in the Community Atmosphere Model (CAM5) is evaluated against measurements over Northern China and the Arctic, and its sensitivity to atmospheric deposition and two parameters that affect post-depositional enrichment is explored. The BCS concentration is overestimated (underestimated) by a factor of two in Northern China (Arctic) in the default model, but agreement with observations is good over both regions in the simulation with improvements in BC transport and deposition. Sensitivity studies indicate that uncertainty in the melt-water scavenging efficiency (MSE) parameter substantially affects BCS and its radiative forcing (by a factor of 2-7) inmore » the Arctic through post-depositional enrichment. The MSE parameter has a relatively small effect on the magnitude of BCS seasonal cycle but can alter its phase in Northern China. The impact of the snow aging scaling factor (SAF) on BCS, partly through the post-depositional enrichment effect, shows more complex latitudinal and seasonal dependence. Similar to MSE, SAF affects more significantly the magnitude (phase) of BCS season cycle over the Arctic (Northern China). While uncertainty associated with the representation of BC transport and deposition processes in CAM5 is more important than that associated with the two snow model parameters in Northern China, the two uncertainties have comparable effect in the Arctic.« less

FACTORS AFFECTING THE UPTAKE OF LISSAMINE GREEN BY SERUM PROTEINS

PubMed Central

Brackenridge, C. J.

1960-01-01

Eight physicochemical factors which affect the uptake of lissamine green on filter paper impregnated with serum proteins have been examined, and their relevance to the staining of electrophoretically separated protein fractions is discussed. It is shown that grade of paper, weight of protein applied, separate and combined denaturation and staining time, temperature and concentration of staining solution, concentration of denaturant, and type of protein all influence the weight of dye absorbed per unit weight of applied protein, and must be rigidly standardized if valid quantitative results are to be obtained. Five sets of conditions are obtained for optimal staining and it is found that separation of denaturant from dye yields the best procedure. It is concluded that lissamine green is an excellent dye for the staining and quantitative estimation of separated protein fractions in paper electrophoresis, and that conditions can usually be arranged to produce a linear relation between dye uptake and protein concentration in an experimentally efficient manner. PMID:13803681

On the selection and evaluation of visual display symbology Factors influencing search and identification times

NASA Technical Reports Server (NTRS)

Remington, Roger; Williams, Douglas

1986-01-01

Three single-target visual search tasks were used to evaluate a set of cathode-ray tube (CRT) symbols for a helicopter situation display. The search tasks were representative of the information extraction required in practice, and reaction time was used to measure the efficiency with which symbols could be located and identified. Familiar numeric symbols were responded to more quickly than graphic symbols. The addition of modifier symbols, such as a nearby flashing dot or surrounding square, had a greater disruptive effect on the graphic symbols than did the numeric characters. The results suggest that a symbol set is, in some respects, like a list that must be learned. Factors that affect the time to identify items in a memory task, such as familiarity and visual discriminability, also affect the time to identify symbols. This analogy has broad implications for the design of symbol sets. An attempt was made to model information access with this class of display.

Performance Acceleration on Production Machines Using the Overall Equipment Effectiveness (OEE) Approach

NASA Astrophysics Data System (ADS)

Mansur, A.; Rayendra, R.; Mastur, MI

2016-01-01

Mistakes during working can trigger a decrease in production level that may lead financial loss to the company. The factors that affect the mistakes are called losses, such as breakdown loss, set up/ adjustment loss, idling and minor stoppage loss, reduced speed loss, reduced yield loss, and rework loss. The objective of the research is to accelerate the performance of the JSW 330T machine in PT. YogyaPresisiTehnikatamaIndustri. JSW 330T is a machine that has the highest downtime numbers. The method for measuring the effectiveness is using the Overall Equipment Effectiveness (OEE). The results of the research show that the JWQ 330T has average rate of the effectiveness (OEE) of 52.66%, availability ratioof 73.43%, performance efficiency rate of 83.58% and quality rate of 84.6%. From the six big losses calculation, the factor that affects the most on the low score of OEE is the breakdown loss which is 58.85% with total time loss of 929.65 hours in a year.

Temperature modelling and prediction for activated sludge systems.

PubMed

Lippi, S; Rosso, D; Lubello, C; Canziani, R; Stenstrom, M K

2009-01-01

Temperature is an important factor affecting biomass activity, which is critical to maintain efficient biological wastewater treatment, and also physiochemical properties of mixed liquor as dissolved oxygen saturation and settling velocity. Controlling temperature is not normally possible for treatment systems but incorporating factors impacting temperature in the design process, such as aeration system, surface to volume ratio, and tank geometry can reduce the range of temperature extremes and improve the overall process performance. Determining how much these design or up-grade options affect the tank temperature requires a temperature model that can be used with existing design methodologies. This paper presents a new steady state temperature model developed by incorporating the best aspects of previously published models, introducing new functions for selected heat exchange paths and improving the method for predicting the effects of covering aeration tanks. Numerical improvements with embedded reference data provide simpler formulation, faster execution, easier sensitivity analyses, using an ordinary spreadsheet. The paper presents several cases to validate the model.

Can ornamental potted plants remove volatile organic compounds from indoor air? A review.

PubMed

Dela Cruz, Majbrit; Christensen, Jan H; Thomsen, Jane Dyrhauge; Müller, Renate

2014-12-01

Volatile organic compounds (VOCs) are found in indoor air, and many of these can affect human health (e.g. formaldehyde and benzene are carcinogenic). Plants affect the levels of VOCs in indoor environments, thus they represent a potential green solution for improving indoor air quality that at the same time can improve human health. This article reviews scientific studies of plants' ability to remove VOCs from indoor air. The focus of the review is on pathways of VOC removal by the plants and factors affecting the efficiency and rate of VOC removal by plants. Laboratory based studies indicate that plant induced removal of VOCs is a combination of direct (e.g. absorption) and indirect (e.g. biotransformation by microorganisms) mechanisms. They also demonstrate that plants' rate of reducing the level of VOCs is influenced by a number of factors such as plant species, light intensity and VOC concentration. For instance, an increase in light intensity has in some studies been shown to lead to an increase in removal of a pollutant. Studies conducted in real-life settings such as offices and homes are few and show mixed results.

Relationships between core factors of knowledge management in hospital nursing organisations and outcomes of nursing performance.

PubMed

Lee, Eun Ju; Kim, Hong Soon; Kim, Hye Young

2014-12-01

The study was conducted to investigate the levels of implementation of knowledge management and outcomes of nursing performance, to examine the relationships between core knowledge management factors and nursing performance outcomes and to identify core knowledge management factors affecting these outcomes. Effective knowledge management is very important to achieve strong organisational performance. The success or failure of knowledge management depends on how effectively an organisation's members share and use their knowledge. Because knowledge management plays a key role in enhancing nursing performance, identifying the core factors and investigating the level of knowledge management in a given hospital are priorities to ensure a high quality of nursing for patients. The study employed a descriptive research procedure. The study sample consisted of 192 nurses registered in three large healthcare organisations in South Korea. The variables demographic characteristics, implementation of core knowledge management factors and outcomes of nursing performance were examined and analysed in this study. The relationships between the core knowledge management factors and outcomes of nursing performance as well as the factors affecting the performance outcomes were investigated. A knowledge-sharing culture and organisational learning were found to be core factors affecting nursing performance. The study results provide basic data that can be used to formulate effective knowledge management strategies for enhancing nursing performance in hospital nursing organisations. In particular, prioritising the adoption of a knowledge-sharing culture and organisational learning in knowledge management systems might be one method for organisations to more effectively manage their knowledge resources and thus to enhance the outcomes of nursing performance and achieve greater business competitiveness. The study results can contribute to the development of effective and efficient knowledge management systems and strategies for enhancing knowledge-sharing culture and organisational learning that can improve both the productivity and competitiveness of healthcare organisations. © 2014 John Wiley & Sons Ltd.

A reassessment of the indicators of primary education quality in developing countries: Emerging evidence from Tanzania

NASA Astrophysics Data System (ADS)

Mosha, Herme Joseph

1988-03-01

This article seeks to identify factors affecting the quality of primary education in five regions of Tanzania by extensively reviewing relevant literature and empirical data. Some of the shortcomings emphasised by the author are: frequent staff turnover, declining financial support for primary education, ineffective curricula, shortage of teachers' guides and textbooks, and unfavourable working conditions for teachers in rural areas. Beyond this, the need for freely available material, efficient school management and regular inspections is stressed by the author.

Test and Evaluation of a Pilot System for Ion Exchange Treatment of Cadmium Cyanide Wastes

DTIC Science & Technology

1993-09-01

rate, metal concentration and solution chemistry , and temperature. These factors affect the diffusion rate of metal ions from the bulk solution to the...Changes in Cd2+ or CN- resin capacity and removal efficiency after a number of regeneration cycles; • Discharge leakage levels of Cd2+ and CN- after...a filter to remove any suspended solids, an activated-carbon column to remove any organic matter (this step was not utilized since organic levels

The Improvement on the Xinjiekou Subway Transfer Channel of Nanjing

NASA Astrophysics Data System (ADS)

Xu, X. D.; Zheng, C. J.

The subway, which is an effective way to alleviate the traffic congestion, has gradually been constructed in many cities. With the completion of the construction, the transfer station will become the factor that affects the efficiency of the whole transport network. Based on investigation and analysis of the present situation of the passenger flow, the essay will make a prediction with the multiple linear regression and put forward two kinds of transfer channel improvement schemes for xinjiekou transfer station.

How much can we gain from improved efficiency? An examination of performance of national HIV/AIDS programs and its determinants in low- and middle-income countries

PubMed Central

2012-01-01

Background The economic downturn exacerbates the inadequacy of resources for combating the worldwide HIV/AIDS pandemic and amplifies the need to improve the efficiency of HIV/AIDS programs. Methods We used data envelopment analysis (DEA) to evaluate efficiency of national HIV/AIDS programs in transforming funding into services and implemented a Tobit model to identify determinants of the efficiency in 68 low- and middle-income countries. We considered the change from the lowest quartile to the average value of a variable a "notable" increase. Results Overall, the average efficiency in implementing HIV/AIDS programs was moderate (49.8%). Program efficiency varied enormously among countries with means by quartile of efficiency of 13.0%, 36.4%, 54.4% and 96.5%. A country's governance, financing mechanisms, and economic and demographic characteristics influence the program efficiency. For example, if countries achieved a notable increase in "voice and accountability" (e.g., greater participation of civil society in policy making), the efficiency of their HIV/AIDS programs would increase by 40.8%. For countries in the lowest quartile of per capita gross national income (GNI), a notable increase in per capita GNI would increase the efficiency of AIDS programs by 45.0%. Conclusions There may be substantial opportunity for improving the efficiency of AIDS services, by providing more services with existing resources. Actions beyond the health sector could be important factors affecting HIV/AIDS service delivery. PMID:22443135

Poor Validity of the DSM-IV Schizoid Personality Disorder Construct as a Diagnostic Category.

PubMed

Hummelen, Benjamin; Pedersen, Geir; Wilberg, Theresa; Karterud, Sigmund

2015-06-01

This study sought to evaluate the construct validity of schizoid personality disorder (SZPD) by investigating a sample of 2,619 patients from the Norwegian Network of Personality-Focused Treatment Programs by a variety of statistical techniques. Nineteen patients (0.7%) reached the diagnostic threshold of SZPD. Results from the factor analyses indicated that SZPD consists of three factors: social detachment, withdrawal, and restricted affectivity/ anhedonia. Overall, internal consistency and diagnostic efficiency were poor and best for the criteria that belong to the social detachment factor. These findings pose serious questions about the clinical utility of SZPD as a diagnostic category. On the other hand, the three factors were in concordance with findings from previous studies and with the trait model for personality disorders in DSM-5, supporting the validity of SZPD as a dimensional construct. The authors recommend that SZPD should be deleted as a diagnostic category in future editions of DSM-5.

Factors influencing message dissemination through social media

NASA Astrophysics Data System (ADS)

Zheng, Zeyu; Yang, Huancheng; Fu, Yang; Fu, Dianzheng; Podobnik, Boris; Stanley, H. Eugene

2018-06-01

Online social networks strongly impact our daily lives. An internet user (a "Netizen") wants messages to be efficiently disseminated. The susceptible-infected-recovered (SIR) dissemination model is the traditional tool for exploring the spreading mechanism of information diffusion. We here test our SIR-based dissemination model on open and real-world data collected from Twitter. We locate and identify phase transitions in the message dissemination process. We find that message content is a stronger factor than the popularity of the sender. We also find that the probability that a message will be forwarded has a threshold that affects its ability to spread, and when the probability is above the threshold the message quickly achieves mass dissemination.

Performance simulation of a plasma magnetohydrodynamic power generator

NASA Astrophysics Data System (ADS)

Huang, Hulin; Li, Linyong; Zhu, Guiping

2018-05-01

The performance of magnetohydrodynamic (MHD) power generator is affected by many issues, among which the load coefficient k is of great importance. This paper reveals the relationship between the k and the performance of MHD generator by numerical simulation on Faraday-type MHD power generator using He/Xe as working plasma. The results demonstrate that the power generation efficiency increases with an increment of the load factor. However, the enthalpy extraction firstly increases then decreases with the load factor increasing. The enthalpy extraction rate reaches the maximum when the load coefficient k equals to 0.625, which infers the best performance of the power generator channel with the maximum electricity production.

Effect of flagella expression on adhesion of Achromobacter piechaudii to chalk surfaces.

PubMed

Nejidat, A; Saadi, I; Ronen, Z

2008-12-01

To examine flagella role and cell motility in adhesion of Achromobacter piechaudii to chalk. Transmission electron microscopy revealed that stationary cells have thicker and longer flagella than logarithmic cells. SDS-PAGE analysis showed that flagellin was more abundant in stationary cells than logarithmic ones. Sonication or inhibition of flagellin synthesis caused a 30% reduction in adhesion to chalk. Preincubation of chalk with flagella extracts reduced adhesion, by 50%. Three motility mutants were isolated. Mutants 94 and 153 were nonmotile, expressed normal levels of flagellin, have regular flagella and exhibited reduced adhesion. Mutant 208 expressed low levels of flagellin, no flagella and a spherical cell shape but with normal adhesion capacity. Multiple cell surface factors affect the adhesion efficiency to chalk. Flagella per se through physical interaction and through cell motility contribute to the adhesion process. The adhesion behaviour of mutant 208 suggests that cell shape can compensate for flagellar removal and motility. Physiological status affects bacterial cell surface properties and hence adhesion efficiency to chalk. This interaction is essential to sustain biodegradation activities and thus, remediation of contaminated chalk aquifers.

[Experimental study on crop photosynthesis, transpiration and high efficient water use].

PubMed

Wang, Huixiao; Liu, Changming

2003-10-01

It is well known that the development of water-saving agriculture is a strategic choice for getting rid of the crisis of water shortage. In this paper, the crop photosynthesis, transpiration, stomatic behavior, and their affecting factors were studied in view of increasing the crop water use efficiency. The experimental results showed that there was a parabola relationship between photosynthesis and transpiration. The transpiration at the maximum photosynthesis was a critical value, above which, transpiration was the luxurious part. The luxurious transpiration could be controlled without affecting photosynthetic production. It is possible that the measures for increasing stomatic resistance and preventing transpiration could save water, and improve photosynthesis and yield as well. The photosynthesis rate increased with photosynthetic active radiation, and the light saturation point for photosynthesis existed. The light saturation point of dry treatment was much lower than that of wet treatment, and the relationship between transpiration and radiation was linear. When the photosynthetic active radiation was bigger than 1,000 mumol.m-2.s-1, some treatments could be carried out for decreasing transpiration and improving photosynthesis.

Policy design and performance of emissions trading markets: an adaptive agent-based analysis.

PubMed

Bing, Zhang; Qinqin, Yu; Jun, Bi

2010-08-01

Emissions trading is considered to be a cost-effective environmental economic instrument for pollution control. However, the pilot emissions trading programs in China have failed to bring remarkable success in the campaign for pollution control. The policy design of an emissions trading program is found to have a decisive impact on its performance. In this study, an artificial market for sulfur dioxide (SO2) emissions trading applying the agent-based model was constructed. The performance of the Jiangsu SO2 emissions trading market under different policy design scenario was also examined. Results show that the market efficiency of emissions trading is significantly affected by policy design and existing policies. China's coal-electricity price system is the principal factor influencing the performance of the SO2 emissions trading market. Transaction costs would also reduce market efficiency. In addition, current-level emissions discharge fee/tax and banking mechanisms do not distinctly affect policy performance. Thus, applying emissions trading in emission control in China should consider policy design and interaction with other existing policies.

Implication of SUMO E3 ligases in nucleotide excision repair.

PubMed

Tsuge, Maasa; Kaneoka, Hidenori; Masuda, Yusuke; Ito, Hiroki; Miyake, Katsuhide; Iijima, Shinji

2015-08-01

Post-translational modifications alter protein function to mediate complex hierarchical regulatory processes that are crucial to eukaryotic cellular function. The small ubiquitin-like modifier (SUMO) is an important post-translational modification that affects transcriptional regulation, nuclear localization, and the maintenance of genome stability. Nucleotide excision repair (NER) is a very versatile DNA repair system that is essential for protection against ultraviolet (UV) irradiation. The deficiencies in NER function remarkably increase the risk of skin cancer. Recent studies have shown that several NER factors are SUMOylated, which influences repair efficiency. However, how SUMOylation modulates NER has not yet been elucidated. In the present study, we performed RNAi knockdown of SUMO E3 ligases and found that, in addition to PIASy, the polycomb protein Pc2 affected the repair of cyclobutane pyrimidine dimers. PIAS1 affected both the removal of 6-4 pyrimidine pyrimidone photoproducts and cyclobutane pyrimidine dimers, whereas other SUMO E3 ligases did not affect the removal of either UV lesion.

Increased reprogramming of human fetal hepatocytes compared with adult hepatocytes in feeder-free conditions.

PubMed

Hansel, Marc C; Gramignoli, Roberto; Blake, William; Davila, Julio; Skvorak, Kristen; Dorko, Kenneth; Tahan, Veysel; Lee, Brian R; Tafaleng, Edgar; Guzman-Lepe, Jorge; Soto-Gutierrez, Alejandro; Fox, Ira J; Strom, Stephen C

2014-01-01

Hepatocyte transplantation has been used to treat liver disease. The availability of cells for these procedures is quite limited. Human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) may be a useful source of hepatocytes for basic research and transplantation if efficient and effective differentiation protocols were developed and problems with tumorigenicity could be overcome. Recent evidence suggests that the cell of origin may affect hiPSC differentiation. Thus, hiPSCs generated from hepatocytes may differentiate back to hepatocytes more efficiently than hiPSCs from other cell types. We examined the efficiency of reprogramming adult and fetal human hepatocytes. The present studies report the generation of 40 hiPSC lines from primary human hepatocytes under feeder-free conditions. Of these, 37 hiPSC lines were generated from fetal hepatocytes, 2 hiPSC lines from normal hepatocytes, and 1 hiPSC line from hepatocytes of a patient with Crigler-Najjar syndrome, type 1. All lines were confirmed reprogrammed and expressed markers of pluripotency by gene expression, flow cytometry, immunocytochemistry, and teratoma formation. Fetal hepatocytes were reprogrammed at a frequency over 50-fold higher than adult hepatocytes. Adult hepatocytes were only reprogrammed with six factors, while fetal hepatocytes could be reprogrammed with three (OCT4, SOX2, NANOG) or four factors (OCT4, SOX2, NANOG, LIN28 or OCT4, SOX2, KLF4, C-MYC). The increased reprogramming efficiency of fetal cells was not due to increased transduction efficiency or vector toxicity. These studies confirm that hiPSCs can be generated from adult and fetal hepatocytes including those with genetic diseases. Fetal hepatocytes reprogram much more efficiently than adult hepatocytes, although both could serve as useful sources of hiPSC-derived hepatocytes for basic research or transplantation.

Tracing a Route and Finding a Shortcut: The Working Memory, Motivational, and Personality Factors Involved.

PubMed

Pazzaglia, Francesca; Meneghetti, Chiara; Ronconi, Lucia

2018-01-01

Wayfinding (WF) is the ability to move around efficiently and find the way from a starting point to a destination. It is a component of spatial navigation, a coordinate and goal-directed movement of one's self through the environment. In the present study, the relationship between WF tasks (route tracing and shortcut finding) and individual factors were explored with the hypothesis that WF tasks would be predicted by different types of cognitive, affective, motivational variables, and personality factors. A group of 116 university students (88 F.) were conducted along a route in a virtual environment and then asked first to trace the same route again, and then to find a shortcut between the start and end points. Several instruments assessing visuospatial working memory, mental rotation ability, self-efficacy, spatial anxiety, positive attitude to exploring, and personality traits were administered. The results showed that a latent spatial ability factor (measured with the visuospatial working memory and mental rotations tests) - controlled for gender - predicted route-tracing performance, while self-report measures of anxiety, efficacy, and pleasure in exploring, and some personality traits were more likely to predict shortcut-finding performance. We concluded that both personality and cognitive abilities affect WF performance, but differently, depending on the requirements of the task.

TU-H-CAMPUS-IeP1-01: Bias and Computational Efficiency of Variance Reduction Methods for the Monte Carlo Simulation of Imaging Detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, D; Badano, A; Sempau, J

Purpose: Variance reduction techniques (VRTs) are employed in Monte Carlo simulations to obtain estimates with reduced statistical uncertainty for a given simulation time. In this work, we study the bias and efficiency of a VRT for estimating the response of imaging detectors. Methods: We implemented Directed Sampling (DS), preferentially directing a fraction of emitted optical photons directly towards the detector by altering the isotropic model. The weight of each optical photon is appropriately modified to maintain simulation estimates unbiased. We use a Monte Carlo tool called fastDETECT2 (part of the hybridMANTIS open-source package) for optical transport, modified for VRT. Themore » weight of each photon is calculated as the ratio of original probability (no VRT) and the new probability for a particular direction. For our analysis of bias and efficiency, we use pulse height spectra, point response functions, and Swank factors. We obtain results for a variety of cases including analog (no VRT, isotropic distribution), and DS with 0.2 and 0.8 optical photons directed towards the sensor plane. We used 10,000, 25-keV primaries. Results: The Swank factor for all cases in our simplified model converged fast (within the first 100 primaries) to a stable value of 0.9. The root mean square error per pixel for DS VRT for the point response function between analog and VRT cases was approximately 5e-4. Conclusion: Our preliminary results suggest that DS VRT does not affect the estimate of the mean for the Swank factor. Our findings indicate that it may be possible to design VRTs for imaging detector simulations to increase computational efficiency without introducing bias.« less

Designed experiment evaluation of key variables affecting the cutting performance of rotary instruments.

PubMed

Funkenbusch, Paul D; Rotella, Mario; Ercoli, Carlo

2015-04-01

Laboratory studies of tooth preparation are often performed under a limited range of conditions involving single values for all variables other than the 1 being tested. In contrast, in clinical settings not all variables can be tightly controlled. For example, a new dental rotary cutting instrument may be tested in the laboratory by making a specific cut with a fixed force, but in clinical practice, the instrument must make different cuts with individual dentists applying a range of different forces. Therefore, the broad applicability of laboratory results to diverse clinical conditions is uncertain and the comparison of effects across studies is difficult. The purpose of this study was to examine the effect of 9 process variables on dental cutting in a single experiment, allowing each variable to be robustly tested over a range of values for the other 8 and permitting a direct comparison of the relative importance of each on the cutting process. The effects of 9 key process variables on the efficiency of a simulated dental cutting operation were measured. A fractional factorial experiment was conducted by using a computer-controlled, dedicated testing apparatus to simulate dental cutting procedures and Macor blocks as the cutting substrate. Analysis of Variance (ANOVA) was used to judge the statistical significance (α=.05). Five variables consistently produced large, statistically significant effects (target applied load, cut length, starting rpm, diamond grit size, and cut type), while 4 variables produced relatively small, statistically insignificant effects (number of cooling ports, rotary cutting instrument diameter, disposability, and water flow rate). The control exerted by the dentist, simulated in this study by targeting a specific level of applied force, was the single most important factor affecting cutting efficiency. Cutting efficiency was also significantly affected by factors simulating patient/clinical circumstances as well as hardware choices. These results highlight the importance of local clinical conditions (procedure, dentist) in understanding dental cutting procedures and in designing adequate experimental methodologies for future studies. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

[Effects of a non-face-to-face behavioral intervention on poor sleepers and factors affecting improvement of sleep].

PubMed

Amamoto, Yuko; Adachi, Yoshiko; Kunituka, Kouko; Kumagai, Shuzo

2010-03-01

The purposes of this study were 1) to re-examine effects obtained from previous research of a non-face-to-face behavioral intervention in poorer sleepers and 2) to examine the factors impacting on improvement of sleep. The subjects were 178 poor sleepers who participated in an intervention for sleep improvement. The educational procedures comprised a minimal behavioral self-help package for one month that featured self- learning and self- monitoring of practical target habits for change. It was non face-to-face program conducted by only one member of staff. Subjects were asked to answer a questionnaire before and after the intervention. To reexamine the effects of this program found in our previous research, 9 sleep indices, sleep quality, and sleep-related behaviors were compared between before and after intervention. The sleep indices were total sleep time, sleep onset latency, sleep efficiency etc. Subjects were divided into an improvement group (n = 63) and a non-improvement group (n = 115) using a cutoff value for average change in sleep onset latency and sleep efficiency. After comparison of sleep and behavior between the two groups, logistic regression analysis was conducted to select parameters affecting improvement with this program. Total sleep time was significantly increased from 5.7 h to 6.1 h, sleep onset time decreased 18 minutes, and sleep efficiency improved 5.6 points. With 8 of 9 sleep-related behaviors, the proportion of subjects having an undesirable habit significantly decreased. The mean total number of desirable habit' changes was 2.63 in the improvement group and significantly higher than the 2.06 in the non-improvement group. Logistic regression analysis demonstrated that large sleep onset latency at baseline and beginning of regular exercise significantly affected the improvement of sleep in the subjects, after adjusting for all other parameters. The effects revealed by our previous research were reconfirmed. It is suggested that this program is more useful for persons having severe sleep onset difficulties, and regular exercise is particularly important in improvement of sleep. It is possible that even simple behavioral intervention is feasible with many subjects to improve sleep and related habits in poor sleepers.

Comparisons of stemflow and its bio-/abiotic influential factors between two xerophytic shrub species

NASA Astrophysics Data System (ADS)

Yuan, Chuan; Gao, Guangyao; Fu, Bojie

2017-03-01

Stemflow transports nutrient-enriched precipitation to the rhizosphere and functions as an efficient terrestrial flux in water-stressed ecosystems. However, its ecological significance has generally been underestimated because it is relatively limited in amount, and the biotic mechanisms that affect it have not been thoroughly studied at the leaf scale. This study was conducted during the 2014 and 2015 rainy seasons at the northern Loess Plateau of China. We measured the branch stemflow volume (SFb), shrub stemflow equivalent water depth (SFd), stemflow percentage of incident precipitation (SF %), stemflow productivity (SFP), funnelling ratio (FR), the meteorological characteristics and the plant traits of branches and leaves of C. korshinskii and S. psammophila. This study evaluated stemflow efficiency for the first time with the combined results of SFP and FR, and sought to determine the inter- and intra-specific differences of stemflow yield and efficiency between the two species, as well as the specific bio-/abiotic mechanisms that affected stemflow. The results indicated that C. korshinskii had a greater stemflow yield and efficiency at all precipitation levels than that of S. psammophila. The largest inter-specific difference generally occurred at the 5-10 mm branches during rains of ≤ 2 mm. Precipitation amount was the most influential meteorological characteristic that affected stemflow yield and efficiency in these two endemic shrub species. Branch angle was the most influential plant trait on FR. For SFb, stem biomass and leaf biomass were the most influential plant traits for C. korshinskii and S. psammophila, respectively. For SFP of these two shrub species, leaf traits (the individual leaf area) and branch traits (branch size and biomass allocation pattern) had a great influence during lighter rains ≤ 10 mm and heavier rains > 15 mm, respectively. The lower precipitation threshold to start stemflow allowed C. korshinskii (0.9 mm vs. 2.1 mm for S. psammophila) to employ more rains to harvest water via stemflow. The beneficial leaf traits (e.g., leaf shape, arrangement, area, amount) might partly explain the greater stemflow production of C. korshinskii. Comparison of SFb between the foliated and manually defoliated shrubs during the 2015 rainy season indicated that the newly exposed branch surface at the defoliated period and the resulting rainfall intercepting effects might be an important mechanism affecting stemflow in the dormant season.

Principal Factors for High Performance of Odor and Methane degrading Biocover using Network Analysis

NASA Astrophysics Data System (ADS)

Jung, H.; Yun, J.; O, G. C.; Ryu, H. W.; Jeon, J. M.; Cho, K. S.

2016-12-01

Methane is 25 times more powerful greenhouse gas than carbon dioxide and plays an important role in global warming. Landfills are one of the biggest methane sources and have emitted 37% of anthropogenic methane in Korea. Applying biocovers in landfills is known to be efficient for the simultaneous mitigation of methane as well as odor which occurs severe civil claims. In this study, three pilot-scale biocovers (2.5mx5mx1m) were constructed in a sanitary landfill at Gwangyang, Korea to establish the optimal operational conditions of biocover. All biocovers are filled with soil, EG microbial agent, food waste compost, and perlite with different combination. Pilot-scale biocovers have been operated since January in this year for simultaneous removal of odor and methane. The concentrations of methane and odors such as ammonia, H2S, methyl mercaptane, methylsulfide, dimetyl disulfide, i-valeraldehyde, and styrene were measured at the inlet and outlet of biocovers each month using GC and HPLC for removal performance evaluation. The biocover with highest removal efficiency eliminated 98.4% of odor and 100.0% of methane. All removal efficiencies of odor measured during experiment are in 81.1 98.4% range, and those of methane are in 3.6 100.0%. Three months later after biocover construction, all biocovers with mixed packing material showed better methane degradation performance than the biocovers packed only with soil. The packing materials of biocovers were sampled during winter (January), spring (April) and summer (July), and their microbial communities were examined based on 16S rDNA using 454 pyrosequencing to detect microbial factors that affects the removal efficiency. Methanotrophs which are known as methane-degradable bacteria take 10 25% of microbial community in biocovers, and most of those found in biocovers are type methanothrophs. Network analysis is performed and principal factors for performance improvement of biocovers are derived. Based on this study, well-designed biocovers will be newly set up in the operational landfill with the consideration of derived principal factors for high efficiency. This research was supported by the Korea Ministry of Environment as a "Converging Technology Project (2015001640003)".

Evaluation of performance and impacts of maternal and child health hospital services using Data Envelopment Analysis in Guangxi Zhuang Autonomous Region, China: a comparison study among poverty and non-poverty county level hospitals.

PubMed

Wang, Xuan; Luo, Hongye; Qin, Xianjin; Feng, Jun; Gao, Hongda; Feng, Qiming

2016-08-23

As the core of the county-level Maternal and Child Health Hospitals (MCHH) in rural areas of China, the service efficiency affects the fairness and availability of healthcare services. This study aims to identify the determinants of hospital efficiency and explore how to improve the performance of MCHH in terms of productivity and efficiency. Data was collected from a sample of 32 county-level MCHHs of Guangxi in 2014. Firstly, we specified and measured the indicators of the inputs and outputs which represent hospital resources expended and its profiles respectively. Then we estimated the efficiency scores using Data Envelopment Analysis (DEA) for each hospital. Efficiency scores were decomposed into technical, scale and congestion components, and the potential output increases and/or input reductions were also estimated in this model, which would make relatively inefficient hospitals more efficient. In the second stage, the estimated efficiency scores are regressed against hospital external and internal environment factors using a Tobit model. We used DEAP (V2.1) and R for data analysis. The average scores of technical efficiency, net technical efficiency (managerial efficiency) and scale efficiency of the hospitals were 0.875, 0.922 and 0.945, respectively. Half of the hospitals were efficient, and 9.4 % and 40.6 % were weakly efficient and inefficient, respectively. Among the low-productiveness hospitals, 61.1 % came from poor counties (Poor counties in this article are in the list of key poverty-stricken counties at the national level, published by The State Council Leading Group Office of Poverty Alleviation and Development, 2012). The total input indicated that redundant medical resources in poverty areas were significantly higher than those in non-poverty areas. The Tobit regression model showed that the technical efficiency was proportional to the total annual incomes, the number of discharge patients, and the number of outpatient and emergency visits, while it was inversely proportional to total expenditure and the actual number of open beds. Technical efficiency was not associated with number of health care workers. The overall operational efficiency of the county-level MCHHs in Guangxi was low and needs to be improved. Regional economic differences affect the performances of hospitals. Health administrations should adjust and optimize the resource investments for the different areas. For the hospitals in poverty areas, policy-makers should not only consider the hardware facilities investment, but also the introduction of advanced techniques and high-level medical personnel to improve their technical efficiency.

Modification of spermatozoa quality in mature small ruminants.

PubMed

Martin, G B; de St Jorre, T Jorre; Al Mohsen, F A; Malecki, I A

2011-01-01

This review is based largely, but not entirely, on the assumption that gamete quality is directly linked to sperm output and thus testicular mass, an approach made necessary by the absence of a large body of data on factors that affect gamete quality in ruminants. On the other hand, there is a change in the efficiency of sperm production per gram of testicular tissue when the testis is growing or shrinking, a clear indicator of changes in the rates of cell loss during the process of spermatogenesis, probably through apoptosis. We therefore postulate that the spermatozoa that do survive when the testis is shrinking are of a lower quality than those that are produced when the testis is growing and the rate of sperm survival is increasing. In adult small ruminants in particular, testicular mass and sperm production are highly labile and can be manipulated by management of photoperiod (melatonin), nutrition, genetics and behaviour ('mating pressure'). Importantly, these factors do not act independently of each other - rather, the outcomes in terms of sperm production are dictated by interactions. It therefore seems likely that spermatozoa quality will be affected by these same factors, but definitive answers await detailed studies.

The impacts of racial group membership on people's distributive justice: an event-related potential study.

PubMed

Wang, Yan; Tang, Yi-Yuan; Deng, Yuqin

2014-04-16

How individuals and societies distribute benefits has long been studied by psychologists and sociologists. Previous work has highlighted the importance of social identity on people's justice concerns. However, it is not entirely clear how racial in-group/out-group relationship affects the brain activity in distributive justice. In this study, event-related potentials were recorded while participants made their decisions about donation allocation. Behavioral results showed that racial in-group factor affected participants' decisions on justice consideration. Participants were more likely to make relatively equity decisions when racial in-group factor was congruent with equity compared with the corresponding incongruent condition. Moreover, this incongruent condition took longer response times than congruent condition. Meanwhile, less equity decisions were made when efficiency was larger in the opposite side to equity than it was equal between the two options. Scalp event-related potential analyses revealed that greater P300 and late positive potential amplitudes were elicited by the incongruent condition compared with the congruent condition. These findings suggest that the decision-making of distributive justice could be modulated by racial group membership, and greater attentional resources or cognitive efforts are required when racial in-group factor and equity conflict with each other.

Improving health, safety and energy efficiency in New Zealand through measuring and applying basic housing standards.

PubMed

Gillespie-Bennett, Julie; Keall, Michael; Howden-Chapman, Philippa; Baker, Michael G

2013-08-02

Substandard housing is a problem in New Zealand. Historically there has been little recognition of the important aspects of housing quality that affect people's health and safety. In this viewpoint article we outline the importance of assessing these factors as an essential step to improving the health and safety of New Zealanders and household energy efficiency. A practical risk assessment tool adapted to New Zealand conditions, the Healthy Housing Index (HHI), measures the physical characteristics of houses that affect the health and safety of the occupants. This instrument is also the only tool that has been validated against health and safety outcomes and reported in the international peer-reviewed literature. The HHI provides a framework on which a housing warrant of fitness (WOF) can be based. The HHI inspection takes about one hour to conduct and is performed by a trained building inspector. To maximise the effectiveness of this housing quality assessment we envisage the output having two parts. The first would be a pass/fail WOF assessment showing whether or not the house meets basic health, safety and energy efficiency standards. The second component would rate each main assessment area (health, safety and energy efficiency), potentially on a five-point scale. This WOF system would establish a good minimum standard for rental accommodation as well encouraging improved housing performance over time. In this article we argue that the HHI is an important, validated, housing assessment tool that will improve housing quality, leading to better health of the occupants, reduced home injuries, and greater energy efficiency. If required, this tool could be extended to also cover resilience to natural hazards, broader aspects of sustainability, and the suitability of the dwelling for occupants with particular needs.

Factors Associated With the Likelihood of Hospitalization Following Emergency Department Visits for Behavioral Health Conditions.

PubMed

Hamilton, Jane E; Desai, Pratikkumar V; Hoot, Nathan R; Gearing, Robin E; Jeong, Shin; Meyer, Thomas D; Soares, Jair C; Begley, Charles E

2016-11-01

Behavioral health-related emergency department (ED) visits have been linked with ED overcrowding, an increased demand on limited resources, and a longer length of stay (LOS) due in part to patients being admitted to the hospital but waiting for an inpatient bed. This study examines factors associated with the likelihood of hospital admission for ED patients with behavioral health conditions at 16 hospital-based EDs in a large urban area in the southern United States. Using Andersen's Behavioral Model of Health Service Use for guidance, the study examined the relationship between predisposing (characteristics of the individual, i.e., age, sex, race/ethnicity), enabling (system or structural factors affecting healthcare access), and need (clinical) factors and the likelihood of hospitalization following ED visits for behavioral health conditions (n = 28,716 ED visits). In the adjusted analysis, a logistic fixed-effects model with blockwise entry was used to estimate the relative importance of predisposing, enabling, and need variables added separately as blocks while controlling for variation in unobserved hospital-specific practices across hospitals and time in years. Significant predisposing factors associated with an increased likelihood of hospitalization following an ED visit included increasing age, while African American race was associated with a lower likelihood of hospitalization. Among enabling factors, arrival by emergency transport and a longer ED LOS were associated with a greater likelihood of hospitalization while being uninsured and the availability of community-based behavioral health services within 5 miles of the ED were associated with lower odds. Among need factors, having a discharge diagnosis of schizophrenia/psychotic spectrum disorder, an affective disorder, a personality disorder, dementia, or an impulse control disorder as well as secondary diagnoses of suicidal ideation and/or suicidal behavior increased the likelihood of hospitalization following an ED visit. The block of enabling factors was the strongest predictor of hospitalization following an ED visit compared to predisposing and need factors. Our findings also provide evidence of disparities in hospitalization of the uninsured and racial and ethnic minority patients with ED visits for behavioral health conditions. Thus, improved access to community-based behavioral health services and an increased capacity for inpatient psychiatric hospitals for treating indigent patients may be needed to improve the efficiency of ED services in our region for patients with behavioral health conditions. Among need factors, a discharge diagnosis of schizophrenia/psychotic spectrum disorder, an affective disorder, a personality disorder, an impulse control disorder, or dementia as well as secondary diagnoses of suicidal ideation and/or suicidal behavior increased the likelihood of hospitalization following an ED visit, also suggesting an opportunity for improving the efficiency of ED care through the provision of psychiatric services to stabilize and treat patients with serious mental illness. © 2016 by the Society for Academic Emergency Medicine.

Linking social norms to efficient conservation investment in payments for ecosystem services

PubMed Central

Chen, Xiaodong; Lupi, Frank; He, Guangming; Liu, Jianguo

2009-01-01

An increasing amount of investment has been devoted to protecting and restoring ecosystem services worldwide. The efficiency of conservation investments, including payments for ecosystem services (PES), has been found to be affected by biological, political, economic, demographic, and social factors, but little is known about the effects of social norms at the neighborhood level. As a first attempt to quantify the effects of social norms, we studied the effects of a series of possible factors on people's intentions of maintaining forest on their Grain-to-Green Program (GTGP) land plots if the program ends. GTGP is one of the world's largest PES programs and plays an important role in global conservation efforts. Our study was conducted in China's Wolong Nature Reserve, home to the world-famous endangered giant pandas and >4,500 farmers. We found that, in addition to conservation payment amounts and program duration, social norms at the neighborhood level had significant impacts on program re-enrollment, suggesting that social norms can be used to leverage participation to enhance the sustainability of conservation benefits from PES programs. Moreover, our results demonstrate that economic and demographic trends also have profound implications for sustainable conservation. Thus, social norms should be incorporated with economic and demographic trends for efficient conservation investments. PMID:19564610

Space solar cell research - Problems and potential

NASA Technical Reports Server (NTRS)

Flood, Dennis J.

1986-01-01

The value of a passive, maintenance-free, renewable energy source was immediately recognized in the early days of the space program, and the silicon solar cell, despite its infancy, was quickly pressed into service. Efficiencies of those early space solar arrays were low, and lifetimes shorter than hoped for, but within a decade significant advances had been made in both areas. Better performance was achieved because of a variety of factors, ranging from improvements in silicon single crystal material, to better device designs, to a better understanding of the factors that affect the performance of a solar cell in space. Chief among the latter, particularly for the mid-to-high altitude (HEO) and geosynchronous (GEO) orbits, are the effects of the naturally occurring particulate radiation environment. Although not as broadly important to the photovoltaic community at large as increased efficiency, the topic of radiation damage is critically important to use of solar cells in space, and is a major component of the NASA research program in space photovoltaics. This paper will give a brief overview of some of the opportunities and challenges for space photovoltaic applications, and will discuss some of the current reseach directed at achieving high efficiency and controlling the effects of radiation damage in space solar cells.

Linking social norms to efficient conservation investment in payments for ecosystem services.

PubMed

Chen, Xiaodong; Lupi, Frank; He, Guangming; Liu, Jianguo

2009-07-14

An increasing amount of investment has been devoted to protecting and restoring ecosystem services worldwide. The efficiency of conservation investments, including payments for ecosystem services (PES), has been found to be affected by biological, political, economic, demographic, and social factors, but little is known about the effects of social norms at the neighborhood level. As a first attempt to quantify the effects of social norms, we studied the effects of a series of possible factors on people's intentions of maintaining forest on their Grain-to-Green Program (GTGP) land plots if the program ends. GTGP is one of the world's largest PES programs and plays an important role in global conservation efforts. Our study was conducted in China's Wolong Nature Reserve, home to the world-famous endangered giant pandas and >4,500 farmers. We found that, in addition to conservation payment amounts and program duration, social norms at the neighborhood level had significant impacts on program re-enrollment, suggesting that social norms can be used to leverage participation to enhance the sustainability of conservation benefits from PES programs. Moreover, our results demonstrate that economic and demographic trends also have profound implications for sustainable conservation. Thus, social norms should be incorporated with economic and demographic trends for efficient conservation investments.

High efficient removal of molybdenum from water by Fe2(SO4)3: Effects of pH and affecting factors in the presence of co-existing background constituents.

PubMed

Zhang, Xiang; Ma, Jun; Lu, Xixin; Huangfu, Xiaoliu; Zou, Jing

2015-12-30

Comparatively investigated the different effects of Fe2(SO4)3 coagulation-filtration and FeCl3 coagulation-filtration on the removal of Mo (VI). And the influence of calcium, sulfate, silicate, phosphate and humic acid (HA) were also studied. The following conclusions can be obtained: (1) compared with the case of FeCl3, Fe2(SO4)3 showed a higher Mo (VI) removal efficiency at pH 4.00-5.00, but an equal removal efficiency at pH 6.00-9.00. (2) The optimum Mo (VI) removal by Fe2(SO4)3 was achieved at pH 5.00-6.00; (3) The presence of calcium can reduce the removal of Mo (VI) over the entire pH range in the present study; (4) The effect of co-existing background anions (including HA) was dominated by three factors: Firstly the influence of co-existing background anions on the content of Fe intercepted from water (intercepted Fe). Secondly the competition of co-existing anions with Mo (VI) for adsorption sites. Thirdly the influence of co-existing background anions on the Zeta potential of the iron flocs. Copyright © 2015 Elsevier B.V. All rights reserved.

Factors influencing in situ gamma-ray measurements

NASA Astrophysics Data System (ADS)

Loonstra, E. H.; van Egmond, F. M.

2009-04-01

Introduction In situ passive gamma-ray sensors are very well suitable for mapping physical soil properties. In order to make a qualitative sound soil map, high quality input parameters for calibration are required. This paper will focus on the factors that affect the output of in situ passive gamma-ray sensors, the primary source, soil, not taken into account. Factors The gamma-ray spectrum contains information of naturally occurring nuclides 40K, 238U and 232Th and man-made nuclides like 137Cs, as well as the total count rate. Factors that influence the concentration of these nuclides and the count rate can be classified in 3 categories. These are sensor design, environmental conditions and operational circumstances. Sensor design The main elements of an in situ gamma-ray sensor that influence the outcome and quality of the output are the crystal and the spectrum analysis method. Material and size of the crystal determine the energy resolution. Though widely used, NaI crystals are not the most efficient capturer of gamma radiation. Alternatives are BGO and CsI. BGO has a low peak resolution, which prohibits use in cases where man-made nuclides are subject of interest. The material is expensive and prone to temperature instability. CsI is robust compared to NaI and BGO. The density of CsI is higher than NaI, yielding better efficiency, especially for smaller crystal sizes. More volume results in higher energy efficiency. The reduction of the measured spectral information into concentration of radionuclides is mostly done using the Windows analysis method. In Windows, the activities of the nuclides are found by summing the intensities of the spectrum found in a certain interval surrounding a peak. A major flaw of the Windows method is the limited amount of spectral information that is incorporated into the analysis. Another weakness is the inherent use of ‘stripping factors' to account for contributions of radiation from nuclide A into the peak of nuclide B. This can be overcome using Full Spectrum Analysis (FSA). This method incorporates virtually all data present in the measured gamma spectrum. In FSA, a Chi-squared algorithm is used to fit a set of "Standard Spectra" to the measured spectrum. The uncertainty in the FSA method is at least a factor 2 lower compared to the Windows method. Environmental conditions Environmental conditions can influence the signal output and therefore the quality. In general, the density of the medium through which gamma-radiation travels determines the interaction of the radiation with matter and thus affects the sensor readings. Excluding soil as being the source; water is the most important external factor in this respect. The amount of water in soil will affect the signal. In general, energy loss occurs as water content in soil increases. As a result, the nuclide concentrations will be lower. Monte Carlo simulations show a difference of 16% in nuclide concentration for completely dry and fully saturated sandy soils. Another water related issue is rainfall. With rain radon gas, a product of 238U, will precipitate. This causes spectral noise effects. Snow and fog have the same effect to a minor degree. Another aspect is the openness of soil. From experience we know that the concentration of 40K differs if soil is tilled. Finally, on earth there is always radioactive noise present from the galaxy. The "Standard Spectra" used in the FSA method can take noise and geometric effects into account. Operational circumstances During a survey an operator should be aware of the effects of driving speed and measurement height. In general, a larger crystal has better energy efficiency and is therefore more suitable for high speed. E.g. a 70 x 150 mm CsI crystal provides qualitative satisfactory output for soil mapping up to 10 km/hr. Sample locations, however, are best measured during a longer period (3 to 5 minutes). The measurement height affects the measurement resolution; the lower the sensor, the smaller the measured area. In addition, Monte Carlo simulations show that the mass of the survey vehicle has to be taken into account. A large tractor e.g. can lead to spectral shape disruptions of 5 to 10%. Conclusion Several factors can effect the measured concentrations of radioactive nuclides. Potential users should take mentioned factors into account in respect to their needs when building and applying gamma-ray sensors. For purposes of soil mapping the use of FSA method is preferred, as it incorporates several disturbing factors. This allows the user to create a consistent dataset which will lead to a better understanding of the relation between nuclide concentrations and physical soil properties.

Deriving depth-dependent light escape efficiency and optical Swank factor from measured pulse height spectra of scintillators.

PubMed

Howansky, Adrian; Peng, Boyu; Lubinsky, Anthony R; Zhao, Wei

2017-03-01

Pulse height spectroscopy has been used by investigators to deduce the imaging properties of scintillators. Pulse height spectra (PHS) are used to compute the Swank factor, which describes the variation in scintillator light output per x-ray interaction. The spread in PHS measured below the K-edge is related to the optical component of the Swank factor, i.e., variations in light escape efficiency from different depths of x-ray interaction in the scintillator, denoted ε¯(z). Optimizing scintillators for medical imaging applications requires understanding of these optical properties, as they determine tradeoffs between parameters such as x-ray absorption, light yield, and spatial resolution. This work develops a model for PHS acquisition such that the effect of measurement uncertainty can be removed. This method allows ε¯(z) to be quantified on an absolute scale and permits more accurate estimation of the optical Swank factor of scintillators. The pulse height spectroscopy acquisition chain was modeled as a linear system of stochastic gain stages. Analytical expressions were derived for signal and noise propagation through the PHS chain, accounting for deterministic and stochastic aspects of x-ray absorption, scintillation, and light detection with a photomultiplier tube. The derived expressions were used to calculate PHS of thallium-doped cesium iodide (CsI) scintillators using parameters that were measured, calculated, or known from literature. PHS were measured at 25 and 32 keV of CsI samples designed with an optically reflective or absorptive backing, with or without a fiber-optic faceplate (FOP), and with thicknesses ranging from 150-1000 μm. Measured PHS were compared with calculated PHS, then light escape model parameters were varied until measured and modeled results reached agreement. Resulting estimates of ε¯(z) were used to calculate each scintillator's optical Swank factor. For scintillators of the same optical design, only minor differences in light escape efficiency were observed between samples with different thickness. As thickness increased, escape efficiency decreased by up to 20% for interactions furthest away from light collection. Optical design (i.e., backing and FOP) predominantly affected the magnitude and relative variation in ε¯(z). Depending on interaction depth and scintillator thickness, samples with an absorptive backing and FOP were estimated to yield 4.1-13.4 photons/keV. Samples with a reflective backing and FOP yielded 10.4-18.4 keV -1 , while those with a reflective backing and no FOP yielded 29.5-52.0 keV -1 . Optical Swank factors were approximately 0.9 and near-unity in samples featuring an absorptive or reflective backing, respectively. This work uses a modeling approach to remove the noise introduced by the measurement apparatus from measured PHS. This method allows absolute quantification of ε¯(z) and more accurate estimation of the optical Swank factor of scintillators. The method was applied to CsI scintillators with different thickness and optical design, and determined that optical design more strongly affects ε¯(z) and Swank factor than differences in CsI thickness. Despite large variations in ε¯(z) between optical designs, the Swank factor of all evaluated samples is above 0.9. Information provided by this methodology can help validate Monte Carlo simulations of structured CsI and optimize scintillator design for x-ray imaging applications. © 2016 American Association of Physicists in Medicine.

Deriving depth-dependent light escape efficiency and optical Swank factor from measured pulse height spectra of scintillators

PubMed Central

Howansky, Adrian; Peng, Boyu; Lubinsky, Anthony R.; Zhao, Wei

2017-01-01

Purpose Pulse height spectroscopy has been used by investigators to deduce the imaging properties of scintillators. Pulse height spectra (PHS) are used to compute the Swank factor, which describes the variation in scintillator light output per x-ray interaction. The spread in PHS measured below the K-edge is related to the optical component of the Swank factor, i.e. variations in light escape efficiency from different depths of x-ray interaction in the scintillator, denoted ε̄(z). Optimizing scintillators for medical imaging applications requires understanding of these optical properties, as they determine tradeoffs between parameters such as x-ray absorption, light yield, and spatial resolution. This work develops a model for PHS acquisition such that the effect of measurement uncertainty can be removed. This method allows ε̄(z) to be quantified on an absolute scale and permits more accurate estimation of the optical Swank factor of scintillators. Methods The pulse height spectroscopy acquisition chain was modeled as a linear system of stochastic gain stages. Analytical expressions were derived for signal and noise propagation through the PHS chain, accounting for deterministic and stochastic aspects of x-ray absorption, scintillation, and light detection with a photomultiplier tube. The derived expressions were used to calculate PHS of thallium-doped cesium iodide (CsI) scintillators using parameters that were measured, calculated, or known from literature. PHS were measured at 25 and 32 keV of CsI samples designed with an optically-reflective or absorptive backing, with or without a fiber-optic faceplate (FOP), and with thicknesses ranging from 150–1000 μm. Measured PHS were compared with calculated PHS, then light escape model parameters were varied until measured and modeled results reached agreement. Resulting estimates of ε̄(z) were used to calculate each scintillator’s optical Swank factor. Results For scintillators of the same optical design, only minor differences in light escape efficiency were observed between samples with different thickness. As thickness increased, escape efficiency decreased by up to 20% for interactions furthest away from light collection. Optical design (i.e. backing and FOP) predominantly affected the magnitude and relative variation in ε̄(z). Depending on interaction depth and scintillator thickness, samples with an absorptive backing and FOP were estimated to yield 4.1–13.4 photons/keV. Samples with a reflective backing and FOP yielded 10.4–18.4 keV−1, while those with a reflective backing and no FOP yielded 29.5–52.0 keV−1. Optical Swank factors were approximately 0.9 and near-unity in samples featuring an absorptive or reflective backing, respectively. Conclusions This work uses a modeling approach to remove the noise introduced by the measurement apparatus from measured PHS. This method allows absolute quantification of ε̄(z) and more accurate estimation of the optical Swank factor of scintillators. The method was applied to CsI scintillators with different thickness and optical design, and determined that optical design more strongly affects ε̄(z) and Swank factor than differences in CsI thickness. Despite large variations in ε̄(z) between optical designs, the Swank factor of all evaluated samples is above 0.9. Information provided by this methodology can help validate Monte Carlo simulations of structured CsI and optimize scintillator design for x-ray imaging applications. PMID:28039881

Numerical investigation of output beam quality in efficient broadband optical parametric chirped pulse amplification

NASA Astrophysics Data System (ADS)

Liu, Xiao-Di; Xu, Lu; Liang, Xiao-Yan

2017-01-01

We theoretically analyzed output beam quality of broad bandwidth non-collinear optical parametric chirped pulse amplification (NOPCPA) in LiB3O5 (LBO) centered at 800 nm. With a three-dimensional numerical model, the influence of the pump intensity, pump and signal spatial modulations, and the walk-off effect on the OPCPA output beam quality are presented, together with conversion efficiency and the gain spectrum. The pump modulation is a dominant factor that affects the output beam quality. Comparatively, the influence of signal modulation is insignificant. For a low-energy system with small beam sizes, walk-off effect has to be considered. Pump modulation and walk-off effect lead to asymmetric output beam profile with increased modulation. A special pump modulation type is found to optimize output beam quality and efficiency. For a high-energy system with large beam sizes, the walk-off effect can be neglected, certain back conversion is beneficial to reduce the output modulation. A trade-off must be made between the output beam quality and the conversion efficiency, especially when the pump modulation is large since. A relatively high conversion efficiency and a low output modulation are both achievable by controlling the pump modulation and intensity.

Parabens abatement from surface waters by electrochemical advanced oxidation with boron doped diamond anodes.

PubMed

Domínguez, Joaquín R; Muñoz-Peña, Maria J; González, Teresa; Palo, Patricia; Cuerda-Correa, Eduardo M

2016-10-01

The removal efficiency of four commonly-used parabens by electrochemical advanced oxidation with boron-doped diamond anodes in two different aqueous matrices, namely ultrapure water and surface water from the Guadiana River, has been analyzed. Response surface methodology and a factorial, composite, central, orthogonal, and rotatable (FCCOR) statistical design of experiments have been used to optimize the process. The experimental results clearly show that the initial concentration of pollutants is the factor that influences the removal efficiency in a more remarkable manner in both aqueous matrices. As a rule, as the initial concentration of parabens increases, the removal efficiency decreases. The current density also affects the removal efficiency in a statistically significant manner in both aqueous matrices. In the water river aqueous matrix, a noticeable synergistic effect on the removal efficiency has been observed, probably due to the presence of chloride ions that increase the conductivity of the solution and contribute to the generation of strong secondary oxidant species such as chlorine or HClO/ClO - . The use of a statistical design of experiments made it possible to determine the optimal conditions necessary to achieve total removal of the four parabens in ultrapure and river water aqueous matrices.

Factors impeding flexible inpatient unit design.

PubMed

Pati, Debajyoti; Evans, Jennie; Harvey, Thomas E; Bazuin, Doug

2012-01-01

To identify and examine factors extraneous to the design decision-making process that could impede the optimization of flexibility on inpatient units. A 2006 empirical study to identify domains of design decisions that affect flexibility on inpatient units found some indication in the context of the acuity-adaptable operational model that factors extraneous to the design process could have negatively influenced the successful implementation of the model. This raised questions regarding extraneous factors that might influence the successful optimization of flexibility. An exploratory, qualitative method was adopted to examine the question. Stakeholders from five recently built acute care inpatient units participated in the study, which involved three types of data collection: (1) verbal protocol data from a gaming session; (2) in-depth semi-structured interviews; and (3) shadowing frontline personnel. Data collection was conducted between June 2009 and November 2010. The study revealed at least nine factors extraneous to the design process that have the potential to hinder the optimization of flexibility in four domains: (1) systemic; (2) cultural; (3) human; and (4) financial. Flexibility is critical to hospital operations in the new healthcare climate, where cost reduction constitutes a vital target. From this perspective, flexibility and efficiency strategies can be influenced by (1) return on investment, (2) communication, (3) culture change, and (4) problem definition. Extraneous factors identified in this study could also affect flexibility in other care settings; therefore, these findings may be viewed from the overall context of hospital design.

Enhancement of ionization efficiency of mass spectrometric analysis from non-electrospray ionization friendly solvents with conventional and novel ionization techniques.

PubMed

Jiang, Ping; Lucy, Charles A

2015-10-15

Electrospray ionization mass spectrometry (ESI-MS) has significantly impacted the analysis of complex biological and petroleum samples. However ESI-MS has limited ionization efficiency for samples in low dielectric and low polarity solvents. Addition of a make-up solvent through a T union or electrospray solvent through continuous flow extractive desorption electrospray ionization (CF-EDESI) enable ionization of analytes in non-ESI friendly solvents. A conventional make-up solvent addition setup was used and a CF-EDESI source was built for ionization of nitrogen-containing standards in hexane or hexane/isopropanol. Factors affecting the performance of both sources have been investigated and optimized. Both the make-up solvent addition and CF-EDESI improve the ionization efficiency for heteroatom compounds in non-ESI friendly solvents. Make-up solvent addition provides higher ionization efficiency than CF-EDESI. Neither the make-up solvent addition nor the CF-EDESI eliminates ionization suppression of nitrogen-containing compounds caused by compounds of the same chemical class. Copyright © 2015 Elsevier B.V. All rights reserved.

An extended cost potential field cellular automata model considering behavior variation of pedestrian flow

NASA Astrophysics Data System (ADS)

Guo, Fang; Li, Xingli; Kuang, Hua; Bai, Yang; Zhou, Huaguo

2016-11-01

The original cost potential field cellular automata describing normal pedestrian evacuation is extended to study more general evacuation scenarios. Based on the cost potential field function, through considering the psychological characteristics of crowd under emergencies, the quantitative formula of behavior variation is introduced to reflect behavioral changes caused by psychology tension. The numerical simulations are performed to investigate the effects of the magnitude of behavior variation, the different pedestrian proportions with different behavior variation and other factors on the evacuation efficiency and process in a room. The spatiotemporal dynamic characteristic during the evacuation process is also discussed. The results show that compared with the normal evacuation, the behavior variation under an emergency does not necessarily lead to the decrease of the evacuation efficiency. At low density, the increase of the behavior variation can improve the evacuation efficiency, while at high density, the evacuation efficiency drops significantly with the increasing amplitude of the behavior variation. In addition, the larger proportion of pedestrian affected by the behavior variation will prolong the evacuation time.

Development of high efficiency Versatile Arc Discharge Ion Source at CERN ISOLDE.

PubMed

Penescu, L; Catherall, R; Lettry, J; Stora, T

2010-02-01

We report here recent developments of Forced Electron Beam Induced Arc Discharge (FEBIAD) ion sources at the ISOLDE radioactive ion beam facility, hosted at the European Organization for Nuclear Research (CERN). As a result of the propositions to improve the ionization efficiency, two FEBIAD prototypes have been produced and successfully tested in 2008. Off-line studies showed that the 1+ ionization efficiencies for noble gases are 5-20 times larger than with the standard ISOLDE FEBIAD ion sources and reach 60% for radon, which allowed the identification at ISOLDE of (229)Rn, an isotope that had never previously been observed in the laboratory. A factor of 3 increase is also expected for the ionization efficiency of the other elements. The experimental and theoretical methodology is presented. The theoretical model, which gives precise insights on the processes affecting the ionization, is used to design optimal sources (grouped under the name of VADIS--Versatile Arc Discharge Ion Source) for the different chemical classes of the produced isotopes, as already demonstrated for the noble gases.

Optimal exploitation of spatially distributed trophic resources and population stability

USGS Publications Warehouse

Basset, A.; Fedele, M.; DeAngelis, D.L.

2002-01-01

The relationships between optimal foraging of individuals and population stability are addressed by testing, with a spatially explicit model, the effect of patch departure behaviour on individual energetics and population stability. A factorial experimental design was used to analyse the relevance of the behavioural factor in relation to three factors that are known to affect individual energetics; i.e. resource growth rate (RGR), assimilation efficiency (AE), and body size of individuals. The factorial combination of these factors produced 432 cases, and 1000 replicate simulations were run for each case. Net energy intake rates of the modelled consumers increased with increasing RGR, consumer AE, and consumer body size, as expected. Moreover, through their patch departure behaviour, by selecting the resource level at which they departed from the patch, individuals managed to substantially increase their net energy intake rates. Population stability was also affected by the behavioural factors and by the other factors, but with highly non-linear responses. Whenever resources were limiting for the consumers because of low RGR, large individual body size or low AE, population density at the equilibrium was directly related to the patch departure behaviour; on the other hand, optimal patch departure behaviour, which maximised the net energy intake at the individual level, had a negative influence on population stability whenever resource availability was high for the consumers. The consumer growth rate (r) and numerical dynamics, as well as the spatial and temporal fluctuations of resource density, which were the proximate causes of population stability or instability, were affected by the behavioural factor as strongly or even more strongly than by the others factors considered here. Therefore, patch departure behaviour can act as a feedback control of individual energetics, allowing consumers to optimise a potential trade-off between short-term individual fitness and long-term population stability. ?? 2002 Elsevier Science B.V. All rights reserved.

Transcription Factor Amr1 Induces Melanin Biosynthesis and Suppresses Virulence in Alternaria brassicicola

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cho, Yangrae; Srivastava, Akhil; Ohm, Robin A.

2012-05-01

Alternaria brassicicola is a successful saprophyte and necrotrophic plant pathogen. Several A. brassicicola genes have been characterized as affecting pathogenesis of Brassica species. To study regulatory mechanisms of pathogenesis, we mined 421 genes in silico encoding putative transcription factors in a machine-annotated, draft genome sequence of A. brassicicola. In this study, targeted gene disruption mutants for 117 of the transcription factor genes were produced and screened. Three of these genes were associated with pathogenesis. Disruption mutants of one gene (AbPacC) were nonpathogenic and another gene (AbVf8) caused lesions less than half the diameter of wild-type lesions. Unexpectedly, mutants of themore » third gene, Amr1, caused lesions with a two-fold larger diameter than the wild type and complementation mutants. Amr1 is a homolog of Cmr1, a transcription factor that regulates melanin biosynthesis in several fungi. We created gene deletion mutants of ?amr1 and characterized their phenotypes. The ?amr1 mutants used pectin as a carbon source more efficiently than the wild type, were melanin-deficient, and more sensitive to UV light and glucanase digestion. The AMR1 protein was localized in the nuclei of hyphae and in highly melanized conidia during the late stage of plant pathogenesis. RNA-seq analysis revealed that three genes in the melanin biosynthesis pathway, along with the deleted Amr1 gene, were expressed at low levels in the mutants. In contrast, many hydrolytic enzyme-coding genes were expressed at higher levels in the mutants than in the wild type during pathogenesis. The results of this study suggested that a gene important for survival in nature negatively affected virulence, probably by a less efficient use of plant cell-wall materials. We speculate that the functions of the Amr1 gene are important to the success of A. brassicicola as a competitive saprophyte and plant parasite.« less

Analysis of exergy efficiency of a super-critical compressed carbon dioxide energy-storage system based on the orthogonal method.

PubMed

He, Qing; Hao, Yinping; Liu, Hui; Liu, Wenyi

2018-01-01

Super-critical carbon dioxide energy-storage (SC-CCES) technology is a new type of gas energy-storage technology. This paper used orthogonal method and variance analysis to make significant analysis on the factors which would affect the thermodynamics characteristics of the SC-CCES system and obtained the significant factors and interactions in the energy-storage process, the energy-release process and the whole energy-storage system. Results have shown that the interactions in the components have little influence on the energy-storage process, the energy-release process and the whole energy-storage process of the SC-CCES system, the significant factors are mainly on the characteristics of the system component itself, which will provide reference for the optimization of the thermal properties of the energy-storage system.

Forward-looking farmers owning multiple potential wetland restoration sites: implications for efficient restoration

NASA Astrophysics Data System (ADS)

Schroder (Kushch), Svetlana; Lang, Zhengxin; Rabotyagov, Sergey

2018-04-01

Wetland restoration can increase the provision of multiple non-market ecosystem services. Environmental and socio-economic factors need to be accounted for when land is withdrawn from agriculture and wetlands are restored. We build multi-objective optimization models to provide decision support for wetland restoration in the Le Sueur river watershed in Southern Minnesota. We integrate environmental objectives of sediment reduction and habitat protection with socio-economic factors associated with the overlap of private land with potential wetland restoration sites in the watershed and the costs representing forward-looking farmers voluntarily taking land out of agricultural production in favor of wetland restoration. Our results demonstrate that the inclusion of these factors early on in the restoration planning process affects both the total costs of the restoration project and the spatial distribution of optimally selected wetland restoration sites.

Analysis of exergy efficiency of a super-critical compressed carbon dioxide energy-storage system based on the orthogonal method

PubMed Central

He, Qing; Liu, Hui; Liu, Wenyi

2018-01-01

Super-critical carbon dioxide energy-storage (SC-CCES) technology is a new type of gas energy-storage technology. This paper used orthogonal method and variance analysis to make significant analysis on the factors which would affect the thermodynamics characteristics of the SC-CCES system and obtained the significant factors and interactions in the energy-storage process, the energy-release process and the whole energy-storage system. Results have shown that the interactions in the components have little influence on the energy-storage process, the energy-release process and the whole energy-storage process of the SC-CCES system, the significant factors are mainly on the characteristics of the system component itself, which will provide reference for the optimization of the thermal properties of the energy-storage system. PMID:29634742

Masticatory efficiency contributing to the improved dynamic postural balance: A cross-sectional study.

PubMed

Hwang, Hae-Yun; Choi, Jun-Seon; Kim, Hee-Eun

2018-05-28

To evaluate whether masticatory efficiency is associated with dynamic postural balance. Masticatory dysfunction can cause deterioration of general health due to nutritional imbalances, thereby negatively affecting postural balance. However, few studies have investigated the association between masticatory efficiency and postural balance. The masticatory efficiency of 74 participants was evaluated by calculating mixing ability index (MAI) using a wax cube. The timed up and go test (TUGT) was used to measure dynamic balance. Participants with an MAI above or below the median value of 1.05 were defined as having high or low masticatory efficiency, respectively. An independent samples t-test was used to identify significant differences in TUGT, according to masticatory efficiency. Analysis of covariance was performed to adjust for confounding factors. Logistic regression analysis was used to assess the correlation between masticatory efficiency and postural balance. The high masticatory efficiency group could complete the TUGT exercise approximately 1.67 seconds faster while maintaining the postural balance, compared to the low masticatory efficiency group (P = .005). Furthermore, the postural imbalance odds of the group with high mastication efficiency decreased by 0.14-fold, relative to the group with low mastication efficiency (95% confidence interval: 0.04-0.46). With some reservations about statistical power, the association found between masticatory efficiency and postural balance justifies further investigations to confirm the strength of the associations, and possibly to identify causal relationships between mastication and posture in old age. © 2018 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

Evaluation of limiting factors affecting photovoltaic performance of low-temperature-processed TiO₂ films in dye-sensitized solar cells.

PubMed

Lee, Taek-Yong; Kim, Hui-Seon; Park, Nam-Gyu

2014-04-14

Limiting factors affecting photovoltaic performance of dye-sensitized solar cell employing low-temperature-processed TiO2 films were investigated. TiO2 films were prepared at a low temperature of 200 °C using the normal alcohol-containing binder-free TiO2 paste (LT200). Their photovoltaic performance was compared to a high-temperature (550 °C) annealed TiO2 film prepared using a polymer binder containing TiO2 paste (HT550). Compared to the proportional increase in conversion efficiency with TiO2 film thickness upto 14 μm for HT550, the increase in efficiency was terminated at relatively smaller thickness of about 8 μm for LT200 mainly due to unaugmented photocurrent. From the transient photocurrent-voltage studies, the electron transport rate was found to be almost identical, while charge recombination was one order of magnitude faster for LT200. Consequently, the electron diffusion length was more than 2-3 times shorter for LT200 than for HT550. Electron diffusion length and electron life time obtained from electrochemical impedance analysis were well consistent with those observed from transient measurement. Density of states (DOS) was evaluated to be shallow and narrow in LT200, which was responsible for limiting photovoltaic performance in the low-temperature processed TiO2 film. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Numerical Simulations of SCR DeNOx System for a 660MW coal-fired power station

NASA Astrophysics Data System (ADS)

Yongqiang, Deng; Zhongming, Mei; Yijun, Mao; Nianping, Liu; Guoming, Yin

2018-06-01

Aimed at the selective catalytic reduction (SCR) DeNOx system of a 660 MW coal-fired power station, which is limited by low denitrification efficiency, large ammonia consumption and over-high ammonia escape rate, numerical simulations were conducted by employing STAR-CCM+ (CFD tool). The simulations results revealed the problems existed in the SCR DeNOx system. Aimed at limitations of the target SCR DeNOx system, factors affecting the denitrification performance of SCR, including the structural parameters and ammonia injected by the ammonia nozzles, were optimized. Under the optimized operational conditions, the denitrification efficiency of the SCR system was enhanced, while the ammonia escape rate was reduced below 3ppm. This study serves as references for optimization and modification of SCR systems.

Functional foods and urban agriculture: two responses to climate change-related food insecurity.

PubMed

Dixon, Jane M; Donati, Kelly J; Pike, Lucy L; Hattersley, Libby

2009-01-01

Affluent diets have negative effects on the health of the population and the environment. Moreover, the ability of industrialised agricultural ecosystems to continue to supply these diets is threatened by the anticipated consequences of climate change. By challenging the ongoing supply the diets of affluent countries, climate change provides a population and environmental health opportunity. This paper contrasts two strategies for dealing with climate change-related food insecurity. Functional foods are being positioned as one response because they are considered a hyper-efficient mechanism for supplying essential micronutrients. An alternative response is civic and urban agriculture. Rather than emphasising increased economic or nutritional efficiencies, civic agriculture presents a holistic approach to food security that is more directly connected to the economic, environmental and social factors that affect diet and health.

Removal of fluorine from contaminated soil by electrokinetic treatment driven by solar energy.

PubMed

Zhou, Ming; Zhu, Shufa; Liu, Yana; Wang, Xuejian

2013-08-01

Instead of direct current power supply, a series of electrokinetic remediation experiments driven by solar energy on fluorine-contaminated soil were conducted in a self-made electrolyzer, in order to reduce energy expenditure of electrokinetic remediation. After the 12-day electrokinetic remediation driven by solar energy, the removal efficiency of fluorine was 22.3%, and electrokinetic treatment had an impact on changes in partitioning of fluorine in soil. It proved that the combination of electrokinetics and solar energy was feasible and effective to some extent for the remediation of fluorine-contaminated soil. Meanwhile, the experimental results also indicated that the electromigration was a more dominant transport mechanism for the removal of fluorine from contaminated soil than electroosmosis, and the weather condition was the important factor in affecting the removal efficiency.

Design and evaluation of liposomal formulation of pilocarpine nitrate.

PubMed

Rathod, S; Deshpande, S G

2010-03-01

Prolonged release drug delivery system of pilocarpine nitrate was made by optimizing thin layer film hydration method. Egg phosphatidylcholine and cholesterol were used to make multilamellar vesicles. Effects of charges over the vesicles were studied by incorporating dicetylphosphate and stearylamine. Various factors, which may affect the size, shape, encapsulation efficiency and release rate, were studied. Liposomes in the size range 0.2 to 1 µm were obtained by optimizing the process. Encapsulation efficiency of neutral, positive and negatively charged liposomes were found to be 32.5, 35.4 and 34.2 percent, respectively. In vitro drug release rate was studied on specially designed model. Biological response in terms of reduction in intraocular pressure was observed on rabbit eyes. Pilocarpine nitrate liposomes were lyophilized and stability studies were conducted.

IT Solution concept development for tracking and analyzing the labor effectiveness of employees

NASA Astrophysics Data System (ADS)

Ilin, Igor; Shirokova, Svetlana; Lepekhin, Aleksandr

2018-03-01

Labor efficiency and productivity of employees is an important aspect for the environment within any type of organization. This is particularly crucial factor for the companies, if which operations are associated with physical labor, such as construction companies. Productivity and efficiency are both very complicated concepts and a huge variety of methods and approaches to its analysis can be implemented within the organization. Despite that, it is important to choose the methods, which not only analyze the key performance indicators of employee, but take into account personal indicators, which might affect performance even more than professional skills. For this complicated analysis task it is important to build IT solution for tracking and analyzing of the labor effectiveness. The concept for designing this IT solution is proposed in the current research.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dernotte, Jeremie; Dec, John E.; Ji, Chunsheng

A detailed understanding of the various factors affecting the trends in gross-indicated thermal efficiency with changes in key operating parameters has been carried out, applied to a one-liter displacement single-cylinder boosted Low-Temperature Gasoline Combustion (LTGC) engine. This work systematically investigates how the supplied fuel energy splits into the following four energy pathways: gross-indicated thermal efficiency, combustion inefficiency, heat transfer and exhaust losses, and how this split changes with operating conditions. Additional analysis is performed to determine the influence of variations in the ratio of specific heat capacities (γ) and the effective expansion ratio, related to the combustion-phasing retard (CA50), onmore » the energy split. Heat transfer and exhaust losses are computed using multiple standard cycle analysis techniques. Furthermore, the various methods are evaluated in order to validate the trends.« less

Electrochromic mirror using viologen-anchored nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Han Na; University of Science and Technology, Advanced Device Technology, 217 Gajeong-roYuseong-gu, Daejeon 305-350; Cho, Seong M.

Highlights: • Three types of ECM device were fabricated using viologen-anchored ECDs. • The devices were investigated according to their optical structures. • The anti-reflection material affects the reflectance and the coloration efficiency. • The device design of ECMs is a crucial factor for clear reflected images. - Abstract: Electrochromic mirrors (ECMs) that are used in automobile mirrors need to have high reflectance, a high contrast ratio, and a clear image. In particular, it is critical that distortions of clear images are minimized for safety. Therefore, an ECM is fabricated using viologen-anchored nanoparticles and a magnesium fluoride (MgF{sub 2}) layermore » with an anti-reflection function. The ECM has approximately 30.42% in the reflectance dynamic range and 125 cm{sup 2}/C high coloration efficiency.« less

Modelling the global efficiency of dissolved air flotation.

PubMed

Leppinen, D M; Dalziel, S B; Linden, P F

2001-01-01

The purpose of this paper is to examine how the efficiency of dissolved air flotation is affected by the size of bubbles and particles. The rise speed of bubble/particle agglomerates is modelled as a function of bubble and particle size, while the kinematics of the bubble attachment process is modelled using the population balance approach adopted by Matsui, Fukushi and Tambo. It is found that flotation, in general, is enhanced by the use of larger particles and larger bubbles. In particular, it is concluded that for the ultra-high surface loading rates of 25 m/hr or more planned for future flotation tanks, bubble size will have to be increased by a factor of two over the size currently employed in many facilities during dissolved air flotation.

Striving towards efficiency in the Greek hospitals by reviewing case mix classifications.

PubMed

Polyzos, Nicholas M

2002-09-01

In order to verify the efficiency level of Greek public hospitals, this paper evaluates the most recent indicators. Relevant data were collected from the two following databases: (a) hospitals' utilisation data generally and per clinical speciality [Ministry of Health, Athens, (Data based) 1995]; (b) Patients' and hospitals' characteristics per diagnosis [National Statistical Office, Athens, (Data based) 1993]. As explanatory variables, the study examines supply and demand factors following case mix classifications. Firstly, average length of stay (ALOS) and secondly, cost per case were regressed as dependent variables. The study highlights the extent of variability across hospitals for different groups of patients with the same condition. The results specify the most important factors that affect ALOS and cost pertaining to efficiency. Per speciality analysis shows occupancy, size-type of the hospital, beds and doctors per speciality, access and use of outpatient services, and surgical operations, etc. as the most significant factors. Per disease-diagnosis analysis shows age of over 65 years, gender, residence, marital status, surgical operation and insurance as the most important factors. General cost analysis in all National Health Systems (NHS) hospitals shows that economies of scale appear in: (a) district and/or specialised hospitals of 250-400 beds; (b) regional and/or teaching hospitals of over but near to 400 beds. Consequently, the author determines the 'Greek' Diagnostic Related Groups (DRGs), based on the cost per clinical speciality in the nine basic specialities and on the cost per diagnosis of the top 15 diagnoses. Further to the scientific results, such studies will enhance much necessary discussions on the organisation of service delivery and financing, by following case mix classification. Copyright 2002 Elsevier Science Ireland Ltd.

Efficiency of chlorophyll in gross primary productivity: A proof of concept and application in crops.

PubMed

Gitelson, Anatoly A; Peng, Yi; Viña, Andrés; Arkebauer, Timothy; Schepers, James S

2016-08-20

One of the main factors affecting vegetation productivity is absorbed light, which is largely governed by chlorophyll. In this paper, we introduce the concept of chlorophyll efficiency, representing the amount of gross primary production per unit of canopy chlorophyll content (Chl) and incident PAR. We analyzed chlorophyll efficiency in two contrasting crops (soybean and maize). Given that they have different photosynthetic pathways (C3 vs. C4), leaf structures (dicot vs. monocot) and canopy architectures (a heliotrophic leaf angle distribution vs. a spherical leaf angle distribution), they cover a large spectrum of biophysical conditions. Our results show that chlorophyll efficiency in primary productivity is highly variable and responds to various physiological and phenological conditions, and water availability. Since Chl is accessible through non-destructive, remotely sensed techniques, the use of chlorophyll efficiency for modeling and monitoring plant optimization patterns is practical at different scales (e.g., leaf, canopy) and under widely-varying environmental conditions. Through this analysis, we directly related a functional characteristic, gross primary production with a structural characteristic, canopy chlorophyll content. Understanding the efficiency of the structural characteristic is of great interest as it allows explaining functional components of the plant system. Copyright © 2016 Elsevier GmbH. All rights reserved.

A stochastic frontier analysis of technical efficiency of fish cage culture in Peninsular Malaysia.

PubMed

Islam, Gazi Md Nurul; Tai, Shzee Yew; Kusairi, Mohd Noh

2016-01-01

Cage culture plays an important role in achieving higher output and generating more export earnings in Malaysia. However, the cost of fingerlings, feed and labour have increased substantially for cage culture in the coastal areas in Peninsular Malaysia. This paper uses farm level data gathered from Manjung, Perak and Kota Tinggi, Johor to investigate the technical efficiency of brackish water fish cage culture using the stochastic frontier approach. The technical efficiency was estimated and specifically the factors affecting technical inefficiencies of fish cage culture system in Malaysia was investigated. On average, 37 percent of the sampled fish cage farms are technically efficient. The results suggest very high degrees of technical inefficiency exist among the cage culturists. This implies that great potential exists to increase fish production through improved efficiency in cage culture management in Peninsular Malaysia. The results indicate that farmers obtained grouper fingerlings from other neighboring countries due to scarcity of fingerlings from wild sources. The cost of feeding for grouper (Epinephelus fuscoguttatus) requires relatively higher costs compared to seabass (Lates calcarifer) production in cage farms in the study areas. Initiatives to undertake extension programmes at the farm level are needed to help cage culturists in utilizing their resources more efficiently in order to substantially enhance their fish production.

An Exponential Luminous Efficiency Model for Hypervelocity Impact into Regolith

NASA Technical Reports Server (NTRS)

Swift, W. R.; Moser, D. E.; Suggs, R. M.; Cooke, W. J.

2011-01-01

The flash of thermal radiation produced as part of the impact-crater forming process can be used to determine the energy of the impact if the luminous efficiency is known. From this energy the mass and, ultimately, the mass flux of similar impactors can be deduced. The luminous efficiency, eta, is a unique function of velocity with an extremely large variation in the laboratory range of under 6 km/s but a necessarily small variation with velocity in the meteoric range of 20 to 70 km/s. Impacts into granular or powdery regolith, such as that on the moon, differ from impacts into solid materials in that the energy is deposited via a serial impact process which affects the rate of deposition of internal (thermal) energy. An exponential model of the process is developed which differs from the usual polynomial models of crater formation. The model is valid for the early time portion of the process and focuses on the deposition of internal energy into the regolith. The model is successfully compared with experimental luminous efficiency data from both laboratory impacts and from lunar impact observations. Further work is proposed to clarify the effects of mass and density upon the luminous efficiency scaling factors. Keywords hypervelocity impact impact flash luminous efficiency lunar impact meteoroid 1

Comparative study of alkylthiols and alkylamines for the phase transfer of gold nanoparticles from an aqueous phase to n-hexane.

PubMed

Li, Lingxiangyu; Leopold, Kerstin; Schuster, Michael

2013-05-01

An efficient ligand-assisted phase transfer method has been developed to transfer gold nanoparticles (Au-NPs, d: 5-25 nm) from an aqueous solution to n-hexane. Four different ligands, namely 1-dodecanethiol (DDT), 1-octadecanethiol (ODT), dodecylamine (DDA), and octadecylamine (ODA) were investigated, and DDT was found to be the most efficient ligand. It appears that the molar ratio of DDT to Au-NPs is a critical factor affecting the transfer efficiency, and 270-310 is found to be the optimum range, under which the transfer efficiency is >96%. Moreover, the DDT-assisted phase transfer can preserve the shape and size of the Au-NPs, which was confirmed by UV-vis spectra and transmission electron microscopy (TEM). Additionally, the transferred Au-NPs still can be well dispersed in the n-hexane phase and remain stable for at least 2 weeks. On the other hand, the ODT-, DDA-, and ODA-assisted phase transfer is fraught with problems either related to transfer efficiency or NPs aggregation. Overall, the DDT-assisted phase transfer of Au-NPs provides a rapid and efficient method to recover Au-NPs from an aqueous solution to n-hexane. Copyright © 2013 Elsevier Inc. All rights reserved.

Multivariate evaluation of the cutting performance of rotary instruments with electric and air-turbine handpieces.

PubMed

Funkenbusch, Paul D; Rotella, Mario; Chochlidakis, Konstantinos; Ercoli, Carlo

2016-10-01

Laboratory studies of tooth preparation often involve single values for all variables other than the one being tested. In contrast, in clinical settings, not all variables can be adequately controlled. For example, a new dental rotary cutting instrument may be tested in the laboratory by making a specific cut with a fixed force, but, in clinical practice, the instrument must make different cuts with individual dentists applying different forces. Therefore, the broad applicability of laboratory results to diverse clinical conditions is uncertain and the comparison of effects across studies difficult. The purpose of this in vitro study was to examine the effects of 9 process variables on the dental cutting of rotary cutting instruments used with an electric handpiece and compare them with those of a previous study that used an air-turbine handpiece. The effects of 9 key process variables on the efficiency of a simulated dental cutting operation were measured. A fractional factorial experiment was conducted by using an electric handpiece in a computer-controlled, dedicated testing apparatus to simulate dental cutting procedures with Macor blocks as the cutting substrate. Analysis of variance (ANOVA) was used to assess the statistical significance (α=.05). Four variables (targeted applied load, cut length, diamond grit size, and cut type) consistently produced large, statistically significant effects, whereas 5 variables (rotation per minute, number of cooling ports, rotary cutting instrument diameter, disposability, and water flow rate) produced relatively small, statistically insignificant effects. These results are generally similar to those previously found for an air-turbine handpiece. Regardless of whether an electric or air-turbine handpiece was used, the control exerted by the dentist, simulated in this study by targeting a specific level of applied force, was the single most important factor affecting cutting efficiency. Cutting efficiency was also significantly affected by factors simulating patient/clinical circumstances and hardware choices. These results highlight the greater importance of local clinical conditions (procedure, dentist) in understanding dental cutting as opposed to other hardware-related factors. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Relative importance of column and adsorption parameters on the productivity in preparative liquid chromatography II: Investigation of separation systems with competitive Langmuir adsorption isotherms.

PubMed

Forssén, Patrik; Samuelsson, Jörgen; Fornstedt, Torgny

2014-06-20

In this study we investigated how the maximum productivity for commonly used, realistic separation system with a competitive Langmuir adsorption isotherm is affected by changes in column length, packing particle size, mobile phase viscosity, maximum allowed column pressure, column efficiency, sample concentration/solubility, selectivity, monolayer saturation capacity and retention factor of the first eluting compound. The study was performed by generating 1000 random separation systems whose optimal injection volume was determined, i.e., the injection volume that gives the largest achievable productivity. The relative changes in largest achievable productivity when one of the parameters above changes was then studied for each system and the productivity changes for all systems were presented as distributions. We found that it is almost always beneficial to use shorter columns with high pressure drops over the column and that the selectivity should be greater than 2. However, the sample concentration and column efficiency have very limited effect on the maximum productivity. The effect of packing particle size depends on the flow rate limiting factor. If the pumps maximum flow rate is the limiting factor use smaller packing, but if the pressure of the system is the limiting factor use larger packing up to about 40μm. Copyright © 2014 Elsevier B.V. All rights reserved.

Efficacy of Bioremediation of Agricultural Runoff Using Bacterial Communities in Woodchip Bioreactors.

NASA Astrophysics Data System (ADS)

Mortensen, Z. H.; Leandro, M.; Silveus, J. M.

2016-12-01

California's agricultural sector is fundamental in the State's economic growth and is responsible for supplying a large portion of the country's produce. In order to meet the market's demand for crop production the region's agrarian landscape requires an abundance of nutrient rich irrigation. The resultant agricultural effluent is a source of increased nutrient content in California's watershed and groundwater systems, promoting eutrophication and contributing to negative impacts on local ecosystems and human health. Previous studies have examined the denitrification potential of woodchip bioreactors. However, research has been deficient regarding specific variables that may affect the remediation process. To evaluate the efficacy of woodchip bioreactors in remediating waters containing high nitrate concentrations, denitrification rates were examined and parameters such as temperature, laminar flow, and hydraulic residence times were measured to identify potential methods for increasing denitrification efficiency. By measuring the rate of denitrification in a controlled environment where potentially confounding factors can be manipulated, physical components affecting the efficiency of woodchip bioreactors were examined to assess effects. Our research suggests the implementation of woodchip bioreactors to treat agricultural runoff would significantly reduce the concentration of nitrate in agricultural effluent and contribute to the mitigation of negative impacts associated with agricultural irrigation. Future research should focus on the ability of woodchip bioreactors to successfully remediate other agricultural pollutants, such as phosphates and pesticides, to optimize the efficiency of the bioremediation process.

An investigation of ground-water recharge by injection in the Palo Alto Baylands, California : hydraulic and chemical interactions; final report

USGS Publications Warehouse

Hamlin, S.N.

1985-01-01

The U.S. Geological Survey, in cooperation with the Santa Clara Valley Water District, has completed a study of ground-water recharge by injection in the Palo Alto baylands along San Francisco Bay, California. Selected wells within the Water District 's injection-extraction network were monitored to determine hydraulic and chemical interactions affecting well-field operation. The well field was installed to prevent and eliminate saline contamination in the local shallow aquifer system. The primary focus of this study is on factors that affect injection efficiency, specifically well and aquifer clogging. Mixing and break-through curves for major chemical constituents indicate ion exchange, adsorption, and dissolution reactions. Freshwater breakthrough was detected in water-level data, which reflected fluid-density change as well as head buildup. Dissolution of calcium carbonate caused by dilution of saline ground water probably accounts for an apparent increase in specific capacity possibly related to improved aquifer permeability. Adsorption evidently removed trace elements during passage of injected water through the aquifer. In terms of hydraulic and chemical compatibility, the well field is a viable system for ground-water recharge. Aquifer heterogeneity and operational constraints reduce the efficiency of the system. Efficiency may be maximized by careful attention to extraction distribution and quantity and to injection distribution, quantity, and water quality. (USGS)

Factors influencing the chance of cows being pregnant 30 days after the herd voluntary waiting period.

PubMed

Löf, E; Gustafsson, H; Emanuelson, U

2014-01-01

The objective of this study was to study factors affecting a reproductive performance indicator at the cow level adjusted for herd management strategy. Associations between the outcome variable, pregnant or not at the herd voluntary waiting period (VWP) plus 30d (pregnant at VWP+30), and the predictor variables were analyzed using a multivariable, generalized estimation equations model that adjusted for clustering of the data at the herd level. The statistical analysis was stratified on parity. In total, 132,721 cows were retained for analyses, of which 29,113 (22%) were pregnant at VWP+30d. Of the nonpregnant cows, 81,483 cows had records of artificial inseminations (AI) and 22,125 cows had no records of AI. The chance of pregnancy was higher for cows of the Swedish Red and for other/crossbreeds compared with Swedish Holstein, for cows from herds with high heat detection efficiency compared with cows from herds with medium and low heat detection efficiency, for cows from herds with long VWP (i.e., >51d) compared with cows from herds with short VWP (<51d), and for cows in freestalls compared with cows in tiestalls. The chance for pregnancy was lower for cows with severe problems at claw trimming compared with cows with no problems at trimming (only for second- and higher-parity cows), for cows that had a record of reproduction-related disease, for cows that had a record of any other disease compared with cows without record, for second- and higher-parity cows with records of dystocia compared with cows with no record of dystocia, for first-parity cows in the group with the highest milk yield compared with first-parity cows in the group with the lowest milk yield, for cows of third and higher parity in the group with the lowest milk yield compared with cows in higher yielding groups, for cows bred in summer compared with those bred in winter-spring (not significant for first-parity cows), and for cows with a twin birth had compared with cows with a single birth. We observed associations of the dose-response type, such that when the milk fat-to-protein ratio increased, the chance for pregnancy decreased, and as the somatic cell count increased, the chance for pregnancy decreased. In conclusion, factors that are known to affect reproductive efficiency also affect the chance of cows being pregnant at the herd VWP plus 30d. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Efficiency and quality of care in nursing homes: an Italian case study.

PubMed

Garavaglia, Giulia; Lettieri, Emanuele; Agasisti, Tommaso; Lopez, Silvano

2011-03-01

This study investigates efficiency and quality of care in nursing homes. By means of Data Envelopment Analysis (DEA), the efficiency of 40 nursing homes that deliver their services in the north-western area of the Lombardy Region was assessed over a 3-year period (2005-2007). Lombardy is a very peculiar setting, since it is the only Region in Italy where the healthcare industry is organised as a quasi-market, in which the public authority buys health and nursing services from independent providers-establishing a reimbursement system for this purpose. The analysis is conducted by generating bootstrapped DEA efficiency scores for each nursing home (stage one), then regressing those scores on explanatory variables (stage two). Our DEA model employed two input (i.e. costs for health and nursing services and costs for residential services) and three output variables (case mix, extra nursing hours and residential charges). In the second-stage analysis, Tobit regressions and the Kruskall-Wallis tests of hypothesis to the efficiency scores were applied to define what are the factors that affect efficiency: (a) the ownership (private nursing houses outperform their public counterparts); and (b) the capability to implement strategies for labour cost and nursing costs containment, since the efficiency heavily depends upon the alignment of the costs to the public reimbursement system. Lastly, even though the public institutions are less efficient than the private ones, the results suggest that public nursing homes are moving towards their private counterparts, and thus competition is benefiting efficiency.

Item Difficulty in the Evaluation of Computer-Based Instruction: An Example from Neuroanatomy

PubMed Central

Chariker, Julia H.; Naaz, Farah; Pani, John R.

2012-01-01

This article reports large item effects in a study of computer-based learning of neuroanatomy. Outcome measures of the efficiency of learning, transfer of learning, and generalization of knowledge diverged by a wide margin across test items, with certain sets of items emerging as particularly difficult to master. In addition, the outcomes of comparisons between instructional methods changed with the difficulty of the items to be learned. More challenging items better differentiated between instructional methods. This set of results is important for two reasons. First, it suggests that instruction may be more efficient if sets of consistently difficult items are the targets of instructional methods particularly suited to them. Second, there is wide variation in the published literature regarding the outcomes of empirical evaluations of computer-based instruction. As a consequence, many questions arise as to the factors that may affect such evaluations. The present paper demonstrates that the level of challenge in the material that is presented to learners is an important factor to consider in the evaluation of a computer-based instructional system. PMID:22231801

Highly Efficient Perovskite Solar Modules by Scalable Fabrication and Interconnection Optimization

DOE PAGES

Yang, Mengjin; Kim, Dong Hoe; Klein, Talysa R.; ...

2018-01-02

To push perovskite solar cell (PSC) technology toward practical applications, large-area perovskite solar modules with multiple subcells need to be developed by fully scalable deposition approaches. Here, we demonstrate a deposition scheme for perovskite module fabrication with spray coating of a TiO2 electron transport layer (ETL) and blade coating of both a perovskite absorber layer and a spiro-OMeTAD-based hole transport layer (HTL). The TiO2 ETL remaining in the interconnection between subcells significantly affects the module performance. Reducing the TiO2 thickness changes the interconnection contact from a Schottky diode to ohmic behavior. Owing to interconnection resistance reduction, the perovskite modules withmore » a 10 nm TiO2 layer show enhanced performance mainly associated with an improved fill factor. Finally, we demonstrate a four-cell MA0.7FA0.3PbI3 perovskite module with a stabilized power conversion efficiency (PCE) of 15.6% measured from an aperture area of ~10.36 cm2, corresponding to an active-area module PCE of 17.9% with a geometric fill factor of ~87.3%.« less

Item difficulty in the evaluation of computer-based instruction: an example from neuroanatomy.

PubMed

Chariker, Julia H; Naaz, Farah; Pani, John R

2012-01-01

This article reports large item effects in a study of computer-based learning of neuroanatomy. Outcome measures of the efficiency of learning, transfer of learning, and generalization of knowledge diverged by a wide margin across test items, with certain sets of items emerging as particularly difficult to master. In addition, the outcomes of comparisons between instructional methods changed with the difficulty of the items to be learned. More challenging items better differentiated between instructional methods. This set of results is important for two reasons. First, it suggests that instruction may be more efficient if sets of consistently difficult items are the targets of instructional methods particularly suited to them. Second, there is wide variation in the published literature regarding the outcomes of empirical evaluations of computer-based instruction. As a consequence, many questions arise as to the factors that may affect such evaluations. The present article demonstrates that the level of challenge in the material that is presented to learners is an important factor to consider in the evaluation of a computer-based instructional system. Copyright © 2011 American Association of Anatomists.

Highly Efficient Perovskite Solar Modules by Scalable Fabrication and Interconnection Optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Mengjin; Kim, Dong Hoe; Klein, Talysa R.

To push perovskite solar cell (PSC) technology toward practical applications, large-area perovskite solar modules with multiple subcells need to be developed by fully scalable deposition approaches. Here, we demonstrate a deposition scheme for perovskite module fabrication with spray coating of a TiO2 electron transport layer (ETL) and blade coating of both a perovskite absorber layer and a spiro-OMeTAD-based hole transport layer (HTL). The TiO2 ETL remaining in the interconnection between subcells significantly affects the module performance. Reducing the TiO2 thickness changes the interconnection contact from a Schottky diode to ohmic behavior. Owing to interconnection resistance reduction, the perovskite modules withmore » a 10 nm TiO2 layer show enhanced performance mainly associated with an improved fill factor. Finally, we demonstrate a four-cell MA0.7FA0.3PbI3 perovskite module with a stabilized power conversion efficiency (PCE) of 15.6% measured from an aperture area of ~10.36 cm2, corresponding to an active-area module PCE of 17.9% with a geometric fill factor of ~87.3%.« less

Energy issues in microwave food processing: A review of developments and the enabling potentials of solid-state power delivery.

PubMed

Atuonwu, J C; Tassou, S A

2018-01-23

The enormous magnitude and variety of microwave applications in household, commercial and industrial food processing creates a strong motivation for improving the energy efficiency and hence, sustainability of the process. This review critically assesses key energy issues associated with microwave food processing, focusing on previous energy performance studies, energy performance metrics, standards and regulations. Factors affecting energy-efficiency are categorised into source, load and source-load matching factors. This highlights the need for highly-flexible and controllable power sources capable of receiving real-time feedback on load properties, and effecting rapid control actions to minimise reflections, heating non-uniformities and other imperfections that lead to energy losses. A case is made for the use of solid-state amplifiers as alternatives to conventional power sources, magnetrons. By a full-scale techno-economic analysis, including energy aspects, it is shown that the use of solid-state amplifiers as replacements to magnetrons is promising, not only from an energy and overall technical perspective, but also in terms of economics.

Effect of clinically-related factors on in vitro blastocyst development after equine ICSI.

PubMed

Choi, Young-Ho; Velez, Isabel C; Macías-García, Beatriz; Riera, Fernando L; Ballard, Catherine S; Hinrichs, Katrin

2016-04-15

Equine intracytoplasmic sperm injection (ICSI) is being used clinically for foal production, but little information is available on factors affecting the efficiency of this procedure. We examined factors that may influence blastocyst development when ICSI is performed clinically, i.e., on oocytes recovered from live mares by transvaginal ultrasound-guided follicle aspiration (TVA), using sperm from the stallion of the client's choice. In a clinical setting, there may be a delay from the time of TVA to isolation of oocytes from the aspirated fluid. In a preliminary study, oocytes from fluid held for 1.5 h at ambient temperature (26°C-33°C) yielded 32% blastocysts; however, in experiment 1, fluid held at 32 °C for 2 h after aspiration yielded 16% blastocysts versus 23% for aspirates processed immediately. Performing TVA/ICSI throughout the year would increase production from valuable mares, but efficiency during the nonbreeding season is unknown. In addition, to reduce the possibility of infection after TVA, administration of antibiotics to the mare before TVA is indicated; however, these could affect oocyte quality. In experiment 2, follicle numbers at the time of TVA were significantly higher in December to January than for the same mares during the breeding season. Oocyte recovery rates on TVA were 60% to 66% and the blastocyst rate was 18%. An equivalent blastocyst rate (18%) was achieved after administration of ampicillin and gentamicin to mares before TVA. In experiment 3, we verified that stallion differences exist in rates of cleavage after ICSI with motile sperm. In sperm from a low-performing stallion, density-gradient centrifugation followed by swim-up was associated with significantly higher rates of cleavage (45% vs. 18%) and blastocyst development (14% vs. 0%) than those for density gradient alone. In experiment 4, parthenogenetic activation with ionomycin and 6-dimethylaminopurine yielded 40% blastocysts. Frozen-thawed sperm that were immotile after nitrogen tank failure did not produce blastocysts; exogenous activation after ICSI increased cleavage rate but did not yield blastocysts. These studies provide information on factors that may affect in vitro blastocyst formation after equine ICSI as it is performed in a clinical program. Copyright © 2016 Elsevier Inc. All rights reserved.

Air Quality Co-benefits of Energy Policy in China: Evidence from Iron & Steel and Cement Industries

NASA Astrophysics Data System (ADS)

Qiu, M.; Weng, Y.; Selin, N. E.; Karplus, V. J.; Cao, J.

2017-12-01

Previous literature has calculated large air quality co-benefits from policies that reduce CO2 emissions and increase energy efficiency. These (often prospective) studies rely on assumptions about how air pollutant emissions respond to energy use changes. Using a unique firm-level data set from China, we examine how a real-world energy efficiency policy affected SO2 emissions, estimate its actual effects on atmospheric PM2.5, and compare to ex ante theoretical estimates. During the 11th Five-year plan (2006-2010), the Chinese government implemented policies directing large energy-consuming firms to reduce their energy consumption per unit of economic output. The Top 1000 Enterprises Program (T1000P) set binding energy intensity targets for China's 1000 highest energy-consuming firms. This program is widely considered a policy success, as 92% of firms met their energy intensity target. Focusing on the cement and iron and steel industry, we examine how T1000P (and related provincial policies) affected firms' SO2 emissions and coal consumption from 2005 to 2008. By comparing T1000P firms with similar firms not subject to the policy, we find that T1000P had a very limited incremental effect on energy use or on air quality co-benefits. Compared to firms not subject to the policy, T1000P firms had 14.7% (cement) and 24.0% (iron & steel) lower reductions in SO2 emission per unit energy use. We also observe large, heterogeneous changes in emission factors (defined as SO2 emissions per unit of coal consumption) among all firms during this period. In comparison to co-benefits estimates that assume constant emission factors, SO2 emissions from T1000P firms in the post-policy period are 23.2% (iron and steel) and 40.2% (cement) lower, but spatially heterogeneous, with some regions experiencing increases. Using the GEOS-Chem model, we estimate the air quality co-benefits of the T1000P policy with realized SO2 emissions changes and compare them with two theoretical estimations of co-benefits: one assuming that emission factors stay the same, and one in which emissions factors decline exponentially with time. We conclude that heterogeneous technology and behavioral responses of covered firms can significantly affect the real-world air quality co-benefits of energy intensity policies delivered by a fixed policy design.

The role of environmental variables on the efficiency of water and sewerage companies: a case study of Chile.

PubMed

Molinos-Senante, María; Sala-Garrido, Ramón; Lafuente, Matilde

2015-07-01

This paper evaluates the efficiency of water and sewerage companies (WaSCs) by introducing the lack of service quality as undesirable outputs. It also investigates whether the production frontier of WaSCs is overall constant returns to scale (CRS) or variable returns to scale (VRS) by using two different data envelopment analysis models. In a second-stage analysis, we study the influence of exogenous and endogenous variables on WaSC performance by applying non-parametric hypothesis tests. In a pioneering approach, the analysis covers 18 WaSCs from Chile, representing about 90% of the Chilean urban population. The results evidence that the technology of the sample studied is characterized overall by CRS. Peak water demand, the percentage of external workers, and the percentage of unbilled water are the factors affecting the efficiency of WaSCs. From a policy perspective, the integration of undesirable outputs into the assessment of WaSC performance is crucial not to penalize companies that provide high service quality to customers.

Theoretical study of the accuracy of the elution by characteristic points method for bi-langmuir isotherms.

PubMed

Ravald, L; Fornstedt, T

2001-01-26

The bi-Langmuir equation has recently been proven essential to describe chiral chromatographic surfaces and we therefore investigated the accuracy of the elution by characteristic points method (ECP) for estimation of bi-Langmuir isotherm parameters. The ECP calculations was done on elution profiles generated by the equilibrium-dispersive model of chromatography for five different sets of bi-Langmuir parameters. The ECP method generates two different errors; (i) the error of the ECP calculated isotherm and (ii) the model error of the fitting to the ECP isotherm. Both errors decreased with increasing column efficiency. Moreover, the model error was strongly affected by the weight of the bi-Langmuir function fitted. For some bi-Langmuir compositions the error of the ECP calculated isotherm is too large even at high column efficiencies. Guidelines will be given on surface types to be avoided and on column efficiencies and loading factors required for adequate parameter estimations with ECP.

Fab is the most efficient format to express functional antibodies by yeast surface display.

PubMed

Sivelle, Coline; Sierocki, Raphaël; Ferreira-Pinto, Kelly; Simon, Stéphanie; Maillere, Bernard; Nozach, Hervé

2018-04-30

Multiple formats are available for engineering of monoclonal antibodies (mAbs) by yeast surface display, but they do not all lead to efficient expression of functional molecules. We therefore expressed four anti-tumor necrosis factor and two anti-IpaD mAbs as single-chain variable fragment (scFv), antigen-binding fragment (Fab) or single-chain Fabs and compared their expression levels and antigen-binding efficiency. Although the scFv and scFab formats are widely used in the literature, 2 of 6 antibodies were either not or weakly expressed. In contrast, all 6 antibodies expressed as Fab revealed strong binding and high affinity, comparable to that of the soluble form. We also demonstrated that the variations in expression did not affect Fab functionality and were due to variations in light chain display and not to misfolded dimers. Our results suggest that Fab is the most versatile format for the engineering of mAbs.

Global map of solar power production efficiency, considering micro climate factors

NASA Astrophysics Data System (ADS)

Hassanpour Adeh, E.; Higgins, C. W.

2017-12-01

Natural resources degradation and greenhouse gas emissions are creating a global crisis. Renewable energy is the most reliable option to mitigate this environmental dilemma. Abundancy of solar energy makes it highly attractive source of electricity. The existing global spatial maps of available solar energy are created with various models which consider the irradiation, latitude, cloud cover, elevation, shading and aerosols, and neglect the influence of local meteorological conditions. In this research, the influences of microclimatological variables on solar energy productivity were investigated with an in-field study at the Rabbit Hills solar arrays near Oregon State University. The local studies were extended to a global level, where global maps of solar power were produced, taking the micro climate variables into account. These variables included: temperature, relative humidity, wind speed, wind direction, solar radiation. The energy balance approach was used to synthesize the data and compute the efficiencies. The results confirmed that the solar power efficiency can be directly affected by the air temperature and wind speed.

Extraction of fullerenes from environmental matrices as affected by solvent characteristics and analyte concentration.

PubMed

Place, Benjamin J; Kleber, Markus; Field, Jennifer A

2013-03-01

Fullerenes possess unique chemical properties that make the isolation of these compounds from heterogeneous environmental matrices difficult. For example, previous reports indicate that toluene-based extraction techniques vary in their ability to extract C60, especially from highly carbonaceous solid matrices. Here, we examined the effects of (i) solvent type (toluene alone versus an 80:20 v/v mixture of toluene and 1-methylnaphthalene) and (ii) analyte concentration on the extraction efficiency of an isotopically labeled surrogate compound, (13)C60. The toluene/1-methylnaphthalene mixture increased fullerene extraction efficiency from carbon lampblack by a factor of five, but was not significantly different from 100% toluene when applied to wood stove soot or montmorillonite. Recovery of the (13)C60 surrogate declined with decreasing analyte concentration. The usefulness of isotopically labeled surrogate is demonstrated and the study provides a quantitative assessment regarding the dependence of fullerene extraction efficiencies on the geochemical characteristics of solid matrices. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Application of statistical experimental design to study the formulation variables influencing the coating process of lidocaine liposomes.

PubMed

González-Rodríguez, M L; Barros, L B; Palma, J; González-Rodríguez, P L; Rabasco, A M

2007-06-07

In this paper, we have used statistical experimental design to investigate the effect of several factors in coating process of lidocaine hydrochloride (LID) liposomes by a biodegradable polymer (chitosan, CH). These variables were the concentration of CH coating solution, the dripping rate of this solution on the liposome colloidal dispersion, the stirring rate, the time since the liposome production to the liposome coating and finally the amount of drug entrapped into liposomes. The selected response variables were drug encapsulation efficiency (EE, %), coating efficiency (CE, %) and zeta potential. Liposomes were obtained by thin-layer evaporation method. They were subsequently coated with CH according the experimental plan provided by a fractional factorial (2(5-1)) screening matrix. We have used spectroscopic methods to determine the zeta potential values. The EE (%) assay was carried out in dialysis bags and the brilliant red probe was used to determine CE (%) due to its property of forming molecular complexes with CH. The graphic analysis of the effects allowed the identification of the main formulation and technological factors by the analysis of the selected responses and permitted the determination of the proper level of these factors for the response improvement. Moreover, fractional design allowed quantifying the interactions between the factors, which will consider in next experiments. The results obtained pointed out that LID amount was the predominant factor that increased the drug entrapment capacity (EE). The CE (%) response was mainly affected by the concentration of the CH solution and the stirring rate, although all the interactions between the main factors have statistical significance.

A single center analysis of factors influencing study start-up timeline in clinical trials.

PubMed

Krafcik, Brianna M; Doros, Gheorghe; Malikova, Marina A

2017-11-01

Efficient start-up phase in clinical trials is crucial to execution. The goal was to determine factors contributing to delays. The start-up milestones were assessed for 38 studies and analyzed. Total start-up time was shorter for following studies: device trials, no outsourcing, fewer ancillary services used and in interventional versus observational designs. The use of a centralized Institutional Review Board (IRB) versus a local IRB reduced time to approval. Studies that never enrolled took longer on average to finalize their budget/contract, and obtain IRB than ones that did enroll. Different features of clinical trials can affect timeline of start-up process. An understanding of the impact of each feature allows for optimization.

Applications of Text Messaging, and Bibliotherapy for Treatment of Patients Affected by Depressive Symptoms.

PubMed

Taleban, Roya; Zamani, Ahmadreza; Moafi, Mohammad; Jiryaee, Nasrin; Khadivi, Reza

2016-01-01

Intensity of depressive symptoms could be exacerbated due to the paucity of appropriate treatments. We assessed the effectiveness of bibliotherapy and text messaging, which aimed at amelioration of patient's behavior and consciousness, which could lead to suicide prevention. This was a randomized clinical trial implemented in rural health centers of Isfahan district (Iran). Health centers were assigned in three trials consisting of the booklet, text messaging, and control groups. Each group consisted of 70 patients. Inclusion criteria were being affected by depressive symptom, <18 years, and cell phone accessibility. Mental retardation, drug and alcohol abuse, visual disability, dementia, suicide attempt history, electrotherapy, and receiving psychological interventions were our not met criteria. Our patient outcomes comprised intensity of depressive symptom and treatment compliance. The first two trials were requested to study instructive booklets in 30 days while the second cohort was demanded to study the booklet in accordance with the daily delivered text messaging. Out of 210 individuals, 198 patients finished this study. The intensity of depressive symptom was significantly affected through time and group factors as well as time-group interaction (F = 12.30, P < 0.001). Based on treatment compliance, the interactive effect of group factor and the time factor was statistically significant. It seems that bibliotherapy could efficiently decrease the intensity of depressive symptoms. Nevertheless, in comparison with our booklet trial, the text messaging group achieved neither durable nor significant success; thus, bibliotherapy could be utilized as a complementary methodology aiming depression treatment.

Source-to-sink transport of sugar and regulation by environmental factors

PubMed Central

Lemoine, Remi; Camera, Sylvain La; Atanassova, Rossitza; Dédaldéchamp, Fabienne; Allario, Thierry; Pourtau, Nathalie; Bonnemain, Jean-Louis; Laloi, Maryse; Coutos-Thévenot, Pierre; Maurousset, Laurence; Faucher, Mireille; Girousse, Christine; Lemonnier, Pauline; Parrilla, Jonathan; Durand, Mickael

2013-01-01

Source-to-sink transport of sugar is one of the major determinants of plant growth and relies on the efficient and controlled distribution of sucrose (and some other sugars such as raffinose and polyols) across plant organs through the phloem. However, sugar transport through the phloem can be affected by many environmental factors that alter source/sink relationships. In this paper, we summarize current knowledge about the phloem transport mechanisms and review the effects of several abiotic (water and salt stress, mineral deficiency, CO2, light, temperature, air, and soil pollutants) and biotic (mutualistic and pathogenic microbes, viruses, aphids, and parasitic plants) factors. Concerning abiotic constraints, alteration of the distribution of sugar among sinks is often reported, with some sinks as roots favored in case of mineral deficiency. Many of these constraints impair the transport function of the phloem but the exact mechanisms are far from being completely known. Phloem integrity can be disrupted (e.g., by callose deposition) and under certain conditions, phloem transport is affected, earlier than photosynthesis. Photosynthesis inhibition could result from the increase in sugar concentration due to phloem transport decrease. Biotic interactions (aphids, fungi, viruses…) also affect crop plant productivity. Recent breakthroughs have identified some of the sugar transporters involved in these interactions on the host and pathogen sides. The different data are discussed in relation to the phloem transport pathways. When possible, the link with current knowledge on the pathways at the molecular level will be highlighted. PMID:23898339

Effects on five species of shorebirds of experimental closure of a beach in New Jersey: implications for severe storms and sea-level rise.

PubMed

Burger, Joanna; Niles, Larry

2014-01-01

For management, it is important to understand the factors that affect foraging efficiency of birds during migration, especially in the face of severe storms and sea-level rise. An experiment was conducted whereby a beach used extensively by migrant shorebirds and people was open and experimentally closed to human activity to examine factors affecting feeding when there was no disturbance, with the beach opened or closed to human activity, and following disturbances. When the beach was closed, the factors affecting the percent of shorebirds foraging varied by species, but involved the number of conspecifics or other shorebirds, location along the beach, and number of raptors. Overall, 30% of flocks were disturbed as a function of type of disturbance, location along the beach, and whether the beach was open or closed. These data suggest that individuals, vehicles, and raptors influence the ability of shorebirds to forage undisturbed, indicating the importance of having some sections of important stopover beaches where shorebirds can feed and roost undisturbed by human activity. A corollary is that other parts of the beach can be freely used by people; environmental health can encompass both protected areas for shorebirds and open areas for fishing and recreation. Severe storms and sea-level rise will limit beach space for both human and avian activities, and understanding mitigation for both is essential to wise adaptive management.

Source-to-sink transport of sugar and regulation by environmental factors.

PubMed

Lemoine, Remi; La Camera, Sylvain; Atanassova, Rossitza; Dédaldéchamp, Fabienne; Allario, Thierry; Pourtau, Nathalie; Bonnemain, Jean-Louis; Laloi, Maryse; Coutos-Thévenot, Pierre; Maurousset, Laurence; Faucher, Mireille; Girousse, Christine; Lemonnier, Pauline; Parrilla, Jonathan; Durand, Mickael

2013-01-01

Source-to-sink transport of sugar is one of the major determinants of plant growth and relies on the efficient and controlled distribution of sucrose (and some other sugars such as raffinose and polyols) across plant organs through the phloem. However, sugar transport through the phloem can be affected by many environmental factors that alter source/sink relationships. In this paper, we summarize current knowledge about the phloem transport mechanisms and review the effects of several abiotic (water and salt stress, mineral deficiency, CO2, light, temperature, air, and soil pollutants) and biotic (mutualistic and pathogenic microbes, viruses, aphids, and parasitic plants) factors. Concerning abiotic constraints, alteration of the distribution of sugar among sinks is often reported, with some sinks as roots favored in case of mineral deficiency. Many of these constraints impair the transport function of the phloem but the exact mechanisms are far from being completely known. Phloem integrity can be disrupted (e.g., by callose deposition) and under certain conditions, phloem transport is affected, earlier than photosynthesis. Photosynthesis inhibition could result from the increase in sugar concentration due to phloem transport decrease. Biotic interactions (aphids, fungi, viruses…) also affect crop plant productivity. Recent breakthroughs have identified some of the sugar transporters involved in these interactions on the host and pathogen sides. The different data are discussed in relation to the phloem transport pathways. When possible, the link with current knowledge on the pathways at the molecular level will be highlighted.

The whole is not the sum of its parts: Specific types of positive affect influence sleep differentially.

PubMed

Pressman, Sarah D; Jenkins, Brooke N; Kraft-Feil, Tara L; Rasmussen, Heather; Scheier, Michael F

2017-08-01

Given the known detrimental effects of poor sleep on an array of psychological and physical health processes, it is critical to understand the factors that protect sleep, especially during times of stress when sleep particularly suffers. Positive affect (PA) arises as a variable of interest given its known associations with health and health behaviors and its ability to buffer stress. In 2 studies, we examined which types of PA (distinguished by arousal level and trait/state measurement) were most beneficial for sleep and whether these associations varied depending on the stress context. In Study 1, college students (N = 99) reported on their PA and sleep during the week of a major exam. In Study 2, 2 weeks of daily PA and sleep data were collected during a period with no examinations in a similar sample of students (N = 83). Results indicated that high trait vigor was tied to better sleep efficiency and quality, especially during high stress. Trait calm was generally unhelpful to sleep, and was related negatively to sleep duration. State calm, on the other hand, interacted with stress in Study 2 to predict more efficient day-to-day sleep on days with higher average stress. These findings illustrate the importance of considering arousal level, affect duration, and the stress context in studies of PA and health. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Dry coolers and air-condensing units (Review)

NASA Astrophysics Data System (ADS)

Milman, O. O.; Anan'ev, P. A.

2016-03-01

The analysis of factors affecting the growth of shortage of freshwater is performed. The state and dynamics of the global market of dry coolers used at electric power plants are investigated. Substantial increase in number and maximum capacity of air-cooled condensers, which have been put into operation in the world in recent years, are noted. The key reasons facilitating the choice of developers of the dry coolers, in particular the independence of the location of thermal power plant from water sources, are enumerated. The main steam turbine heat removal schemes using air cooling are considered, their comparison of thermal efficiency is assessed, and the change of three important parameters, such as surface area of heat transfer, condensate pump flow, and pressure losses in the steam exhaust system, are estimated. It is shown that the most effective is the scheme of direct steam condensation in the heat-exchange tubes, but other schemes also have certain advantages. The air-cooling efficiency may be enhanced much more by using an air-cooling hybrid system: a combination of dry and wet cooling. The basic applied constructive solutions are shown: the arrangement of heat-exchange modules and the types of fans. The optimal mounting design of a fully shopassembled cooling system for heat-exchange modules is represented. Different types of heat-exchange tubes ribbing that take into account the operational features of cooling systems are shown. Heat transfer coefficients of the plants from different manufacturers are compared, and the main reasons for its decline are named. When using evaporative air cooling, it is possible to improve the efficiency of air-cooling units. The factors affecting the faultless performance of dry coolers (DC) and air-condensing units (ACU) and the ways of their elimination are described. A high velocity wind forcing reduces the efficiency of cooling systems and creates preconditions for the development of wind-driven devices. It is noted that global trends have a significant influence on the application of dry coolers in Russia, in view of the fact that some TPP have a surface condensers arrangement. The reasons that these systems are currently less efficient than the direct steam condensation in an air-cooled condenser are explained. It is shown that, in some cases, it is more reasonable to use mixing-type condensers in combination with a dry cooler. Measures for a full import substitution of steam exhaust heat removal systems are mentioned.

Modelling foraging movements of diving predators: a theoretical study exploring the effect of heterogeneous landscapes on foraging efficiency

PubMed Central

Bartoń, Kamil A.; Scott, Beth E.; Travis, Justin M.J.

2014-01-01

Foraging in the marine environment presents particular challenges for air-breathing predators. Information about prey capture rates, the strategies that diving predators use to maximise prey encounter rates and foraging success are still largely unknown and difficult to observe. As well, with the growing awareness of potential climate change impacts and the increasing interest in the development of renewable sources it is unknown how the foraging activity of diving predators such as seabirds will respond to both the presence of underwater structures and the potential corresponding changes in prey distributions. Motivated by this issue we developed a theoretical model to gain general understanding of how the foraging efficiency of diving predators may vary according to landscape structure and foraging strategy. Our theoretical model highlights that animal movements, intervals between prey capture and foraging efficiency are likely to critically depend on the distribution of the prey resource and the size and distribution of introduced underwater structures. For multiple prey loaders, changes in prey distribution affected the searching time necessary to catch a set amount of prey which in turn affected the foraging efficiency. The spatial aggregation of prey around small devices (∼ 9 × 9 m) created a valuable habitat for a successful foraging activity resulting in shorter intervals between prey captures and higher foraging efficiency. The presence of large devices (∼ 24 × 24 m) however represented an obstacle for predator movement, thus increasing the intervals between prey captures. In contrast, for single prey loaders the introduction of spatial aggregation of the resources did not represent an advantage suggesting that their foraging efficiency is more strongly affected by other factors such as the timing to find the first prey item which was found to occur faster in the presence of large devices. The development of this theoretical model represents a useful starting point to understand the energetic reasons for a range of potential predator responses to spatial heterogeneity and environmental uncertainties in terms of search behaviour and predator–prey interactions. We highlight future directions that integrated empirical and modelling studies should take to improve our ability to predict how diving predators will be impacted by the deployment of manmade structures in the marine environment. PMID:25250211

Kinetics of DNA Tile Dimerization

PubMed Central

2015-01-01

Investigating how individual molecular components interact with one another within DNA nanoarchitectures, both in terms of their spatial and temporal interactions, is fundamentally important for a better understanding of their physical behaviors. This will provide researchers with valuable insight for designing more complex higher-order structures that can be assembled more efficiently. In this report, we examined several spatial factors that affect the kinetics of bivalent, double-helical (DH) tile dimerization, including the orientation and number of sticky ends (SEs), the flexibility of the double helical domains, and the size of the tiles. The rate constants we obtained confirm our hypothesis that increased nucleation opportunities and well-aligned SEs accelerate tile–tile dimerization. Increased flexibility in the tiles causes slower dimerization rates, an effect that can be reversed by introducing restrictions to the tile flexibility. The higher dimerization rates of more rigid tiles results from the opposing effects of higher activation energies and higher pre-exponential factors from the Arrhenius equation, where the pre-exponential factor dominates. We believe that the results presented here will assist in improved implementation of DNA tile based algorithmic self-assembly, DNA based molecular robotics, and other specific nucleic acid systems, and will provide guidance to design and assembly processes to improve overall yield and efficiency. PMID:24794259

Kinetics of DNA tile dimerization.

PubMed

Jiang, Shuoxing; Yan, Hao; Liu, Yan

2014-06-24

Investigating how individual molecular components interact with one another within DNA nanoarchitectures, both in terms of their spatial and temporal interactions, is fundamentally important for a better understanding of their physical behaviors. This will provide researchers with valuable insight for designing more complex higher-order structures that can be assembled more efficiently. In this report, we examined several spatial factors that affect the kinetics of bivalent, double-helical (DH) tile dimerization, including the orientation and number of sticky ends (SEs), the flexibility of the double helical domains, and the size of the tiles. The rate constants we obtained confirm our hypothesis that increased nucleation opportunities and well-aligned SEs accelerate tile-tile dimerization. Increased flexibility in the tiles causes slower dimerization rates, an effect that can be reversed by introducing restrictions to the tile flexibility. The higher dimerization rates of more rigid tiles results from the opposing effects of higher activation energies and higher pre-exponential factors from the Arrhenius equation, where the pre-exponential factor dominates. We believe that the results presented here will assist in improved implementation of DNA tile based algorithmic self-assembly, DNA based molecular robotics, and other specific nucleic acid systems, and will provide guidance to design and assembly processes to improve overall yield and efficiency.

Improved quantification of microbial CH4 oxidation efficiency in arctic wetland soils using carbon isotope fractionation

NASA Astrophysics Data System (ADS)

Preuss, I.; Knoblauch, C.; Gebert, J.; Pfeiffer, E.-M.

2013-04-01

Permafrost-affected tundra soils are significant sources of the climate-relevant trace gas methane (CH4). The observed accelerated warming of the arctic will cause deeper permafrost thawing, followed by increased carbon mineralization and CH4 formation in water-saturated tundra soils, thus creating a positive feedback to climate change. Aerobic CH4 oxidation is regarded as the key process reducing CH4 emissions from wetlands, but quantification of turnover rates has remained difficult so far. The application of carbon stable isotope fractionation enables the in situ quantification of CH4 oxidation efficiency in arctic wetland soils. The aim of the current study is to quantify CH4 oxidation efficiency in permafrost-affected tundra soils in Russia's Lena River delta based on stable isotope signatures of CH4. Therefore, depth profiles of CH4 concentrations and δ13CH4 signatures were measured and the fractionation factors for the processes of oxidation (αox) and diffusion (αdiff) were determined. Most previous studies employing stable isotope fractionation for the quantification of CH4 oxidation in soils of other habitats (such as landfill cover soils) have assumed a gas transport dominated by advection (αtrans = 1). In tundra soils, however, diffusion is the main gas transport mechanism and diffusive stable isotope fractionation should be considered alongside oxidative fractionation. For the first time, the stable isotope fractionation of CH4 diffusion through water-saturated soils was determined with an αdiff = 1.001 ± 0.000 (n = 3). CH4 stable isotope fractionation during diffusion through air-filled pores of the investigated polygonal tundra soils was αdiff = 1.013 ± 0.003 (n = 18). Furthermore, it was found that αox differs widely between sites and horizons (mean αox = 1.017 ± 0.009) and needs to be determined on a case by case basis. The impact of both fractionation factors on the quantification of CH4 oxidation was analyzed by considering both the potential diffusion rate under saturated and unsaturated conditions and potential oxidation rates. For a submerged, organic-rich soil, the data indicate a CH4 oxidation efficiency of 50% at the anaerobic-aerobic interface in the upper horizon. The improved in situ quantification of CH4 oxidation in wetlands enables a better assessment of current and potential CH4 sources and sinks in permafrost-affected ecosystems and their potential strengths in response to global warming.

Improved quantification of microbial CH4 oxidation efficiency in Arctic wetland soils using carbon isotope fractionation

NASA Astrophysics Data System (ADS)

Preuss, I.; Knoblauch, C.; Gebert, J.; Pfeiffer, E.-M.

2012-12-01

Permafrost-affected tundra soils are significant sources of the climate-relevant trace gas methane (CH4). The observed accelerated warming of the Arctic will cause a deeper permafrost thawing followed by increased carbon mineralization and CH4 formation in water saturated tundra soils which might cause a positive feedback to climate change. Aerobic CH4 oxidation is regarded as the key process reducing CH4 emissions from wetlands, but quantification of turnover rates has remained difficult so far. The application of carbon stable isotope fractionation enables the in situ quantification of CH4 oxidation efficiency in arctic wetland soils. The aim of the current study is to quantify CH4 oxidation efficiency in permafrost-affected tundra soils in Russia's Lena River Delta based on stable isotope signatures of CH4. Therefore, depth profiles of CH4 concentrations and δ13CH4-signatures were measured and the fractionation factors for the processes of oxidation (αox) and diffusion (αdiff) were determined. Most previous studies employing stable isotope fractionation for the quantification of CH4 oxidation in soils of other habitats (e.g. landfill cover soils) have assumed a gas transport dominated by advection (αtrans = 1). In tundra soils, however, diffusion is the main gas transport mechanism, aside from ebullition. Hence, diffusive stable isotope fractionation has to be considered. For the first time, the stable isotope fractionation of CH4 diffusion through water-saturated soils was determined with an αdiff = 1.001 ± 0.000 (n = 3). CH4 stable isotope fractionation during diffusion through air-filled pores of the investigated polygonal tundra soils was αdiff = 1.013 ± 0.003 (n = 18). Furthermore, it was found that αox differs widely between sites and horizons (mean αox, = 1.017 ± 0.009) and needs to be determined individually. The impact of both fractionation factors on the quantification of CH4 oxidation was analyzed by considering both the potential diffusion rate under saturated and unsaturated conditions and potential oxidation rates. For a submerged organic rich soil, the data indicate a CH4 oxidation efficiency of 50% at the anaerobic-aerobic interface in the upper horizon. The improved in situ quantification of CH4 oxidation in wetlands enables a better assessment of current and potential CH4 sources and sinks in permafrost affected ecosystems and their potential strengths in response to global warming.

Nonadiabatic Electron-Optical System of a Technological Gyrotron

NASA Astrophysics Data System (ADS)

Goldenberg, A. L.; Glyavin, M. Yu.; Leshcheva, K. A.; Manuilov, V. N.

2017-10-01

We consider a new version of the nonadiabatic system for the formation of a helical electron beam in a gyrotron, in which electrons acquire initial oscillatory velocities when a rectilinear beam is injected at an angle to the magnetic field. In such an electron gun, the influence of thermal electron velocities and roughness of the emitting surface can be decreased, as compared with the conventional electron-optical systems of gyrotrons. This makes it possible to increase significantly the system efficiency. The main factors affecting the quality of the formed beam are considered.

Proceedings: Annual Conference of the Military Testing Association (24th) Held at San Antonio, Texas on 1-5 November 1982

DTIC Science & Technology

1983-03-25

influenced by external factors. 7. Controllable by client group . Members of the organization under study should be able to affect the outcome being measured. 8... Group B was tasked to develop six to nine "Indicators" of efficiency and effectiveness for each KRA. Each organization in the study was visited by a...second day, Group A was formed and KRAs were developed. Days three and four involved the generation of Indicators by Group B. Day five consisted of a

Genomic selection in domestic animals: Principles, applications and perspectives.

PubMed

Boichard, Didier; Ducrocq, Vincent; Croiseau, Pascal; Fritz, Sébastien

2016-01-01

The principles of genomic selection are described, with the main factors affecting its efficiency and the assumptions underlying the different models proposed. The reasons of its fast adoption in dairy cattle are explained and the conditions of its application to other species are discussed. Perspectives of development include: selection for new traits and new breeding objectives; adoption of more robust approaches based on information on causal variants; predictions of genotype×environment interactions. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Bed Capacity Planning Using Stochastic Simulation Approach in Cardiac-surgery Department of Teaching Hospitals, Tehran, Iran

PubMed Central

TORABIPOUR, Amin; ZERAATI, Hojjat; ARAB, Mohammad; RASHIDIAN, Arash; AKBARI SARI, Ali; SARZAIEM, Mahmuod Reza

2016-01-01

Background: To determine the hospital required beds using stochastic simulation approach in cardiac surgery departments. Methods: This study was performed from Mar 2011 to Jul 2012 in three phases: First, collection data from 649 patients in cardiac surgery departments of two large teaching hospitals (in Tehran, Iran). Second, statistical analysis and formulate a multivariate linier regression model to determine factors that affect patient's length of stay. Third, develop a stochastic simulation system (from admission to discharge) based on key parameters to estimate required bed capacity. Results: Current cardiac surgery department with 33 beds can only admit patients in 90.7% of days. (4535 d) and will be required to over the 33 beds only in 9.3% of days (efficient cut off point). According to simulation method, studied cardiac surgery department will requires 41–52 beds for admission of all patients in the 12 next years. Finally, one-day reduction of length of stay lead to decrease need for two hospital beds annually. Conclusion: Variation of length of stay and its affecting factors can affect required beds. Statistic and stochastic simulation model are applied and useful methods to estimate and manage hospital beds based on key hospital parameters. PMID:27957466

Optimizing Air Transportation Service to Metroplex Airports. Par 2; Analysis Using the Airline Schedule Optimization Model (ASOM)

NASA Technical Reports Server (NTRS)

Donoue, George; Hoffman, Karla; Sherry, Lance; Ferguson, John; Kara, Abdul Qadar

2010-01-01

The air transportation system is a significant driver of the U.S. economy, providing safe, affordable, and rapid transportation. During the past three decades airspace and airport capacity has not grown in step with demand for air transportation; the failure to increase capacity at the same rate as the growth in demand results in unreliable service and systemic delay. This report describes the results of an analysis of airline strategic decision-making that affects geographic access, economic access, and airline finances, extending the analysis of these factors using historic data (from Part 1 of the report). The Airline Schedule Optimization Model (ASOM) was used to evaluate how exogenous factors (passenger demand, airline operating costs, and airport capacity limits) affect geographic access (markets-served, scheduled flights, aircraft size), economic access (airfares), airline finances (profit), and air transportation efficiency (aircraft size). This analysis captures the impact of the implementation of airport capacity limits, as well as the effect of increased hedged fuel prices, which serve as a proxy for increased costs per flight that might occur if auctions or congestion pricing are imposed; also incorporated are demand elasticity curves based on historical data that provide information about how passenger demand is affected by airfare changes.

National plan to enhance aviation safety through human factors improvements

NASA Technical Reports Server (NTRS)

Foushee, Clay

1990-01-01

The purpose of this section of the plan is to establish a development and implementation strategy plan for improving safety and efficiency in the Air Traffic Control (ATC) system. These improvements will be achieved through the proper applications of human factors considerations to the present and future systems. The program will have four basic goals: (1) prepare for the future system through proper hiring and training; (2) develop a controller work station team concept (managing human errors); (3) understand and address the human factors implications of negative system results; and (4) define the proper division of responsibilities and interactions between the human and the machine in ATC systems. This plan addresses six program elements which together address the overall purpose. The six program elements are: (1) determine principles of human-centered automation that will enhance aviation safety and the efficiency of the air traffic controller; (2) provide new and/or enhanced methods and techniques to measure, assess, and improve human performance in the ATC environment; (3) determine system needs and methods for information transfer between and within controller teams and between controller teams and the cockpit; (4) determine how new controller work station technology can optimally be applied and integrated to enhance safety and efficiency; (5) assess training needs and develop improved techniques and strategies for selection, training, and evaluation of controllers; and (6) develop standards, methods, and procedures for the certification and validation of human engineering in the design, testing, and implementation of any hardware or software system element which affects information flow to or from the human.

c-Jun controls the efficiency of MAP kinase signaling by transcriptional repression of MAP kinase phosphatases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sprowles, Amy; Robinson, Dan; Wu Yimi

2005-08-15

The mammalian JNK signaling pathway regulates the transcriptional response of cells to environmental stress, including UV irradiation. This signaling pathway is composed of a classical MAP kinase cascade; activation results in phosphorylation of the transcription factor substrates c-Jun and ATF2, and leads to changes in gene expression. The defining components of this pathway are conserved in the fission yeast S. pombe, where the genetic studies have shown that the ability of the JNK homolog Spc1 to be activated in response to UV irradiation is dependent on the presence of the transcription factor substrate Atf1. We have used genetic analysis tomore » define the role of c-Jun in activation of the mammalian JNK signaling pathway. Our results show that optimal activation of JNK requires the presence of its transcription factor substrate c-Jun. Mutational analysis shows that the ability of c-Jun to support efficient activation of JNK requires the ability of Jun to bind DNA, suggesting a transcriptional mechanism. Consistent with this, we show that c-Jun represses the expression of several MAP kinase phosphatases. In the absence of c-Jun, the increased expression of MAP kinase phosphatases leads to impaired activation of the ERK, JNK, and p38 MAP kinases after pathway activation. The results show that one function of c-Jun is to regulate the efficiency of signaling by the ERK, p38, and JNK MAP kinases, a function that is likely to affect cellular responses to many different stimuli.« less

Improvement of the performances of a tandem simulated moving bed chromatography by controlling the yield level of a key product of the first simulated moving bed unit.

PubMed

Mun, Sungyong; Wang, Nien-Hwa Linda

2017-03-10

One of the trustworthy processes for ternary separation is a tandem simulated moving bed (SMB) process, which consists of two subordinate four-zone SMB units (Ring I and Ring II). To take full advantage of a tandem SMB as a means of recovering all three products with high purities and high economical efficiency, it is important to understand how the separation condition in Ring II is affected by that in Ring I, and further to reflect such point in the stage of designing a tandem SMB. In regard to such issue, it was clarified in this study that the Ring I factors affecting the Ring II condition could be represented by the yield level of a key product of Ring I (Y key RingI ). As the Y key RingI level became higher, the amount of the Ring I key-product that was reloaded into Ring II was reduced, which affected favorably the Ring II separation condition. On the other hand, the higher Y key RingI level caused a larger dilution for the stream from Ring I to Ring II, which affected adversely the Ring II separation condition. As a result, a minimum in the desorbent usage of a tandem SMB occurred at the Y key RingI level where the two aforementioned factors could be balanced with each other. If such an optimal Y key RingI level was adopted, the desorbent usage could be reduced by up to 25%. It was also found that as the throughput of a tandem SMB became higher, the factor related to the migration of the Ring I key-product into Ring II was more influential in the performances of a tandem SMB than the factor related to the dilution of the stream from Ring I to Ring II. Copyright © 2016 Elsevier B.V. All rights reserved.

Preparation and properties of chitosan-metal complex: Some factors influencing the adsorption capacity for dyes in aqueous solution.

PubMed

Rashid, Sadia; Shen, Chensi; Yang, Jing; Liu, Jianshe; Li, Jing

2018-04-01

Chitosan-metal complexes have been widely studied in wastewater treatment, but there are still various factors in complex preparation which are collectively responsible for improving the adsorption capacity need to be further studied. Thus, this study investigates the factors affecting the adsorption ability of chitosan-metal complex adsorbents, including various kinds of metal centers, different metal salts and crosslinking degree. The results show that the chitosan-Fe(III) complex prepared by sulfate salts exhibited the best adsorption efficiency (100%) for various dyes in very short time duration (10min), and its maximum adsorption capacity achieved 349.22mg/g. The anion of the metal salt which was used in preparation played an important role to enhance the adsorption ability of chitosan-metal complex. SO 4 2- ions not only had the effect of crosslinking through electrostatic interaction with amine group of chitosan polymer, but also could facilitate the chelation of metal ions with chitosan polymer during the synthesis process. Additionally, the pH sensitivity and the sensitivity of ionic environment for chitosan-metal complex were analyzed. We hope that these factors affecting the adsorption of the chitosan-metal complex can help not only in optimizing its use but also in designing new chitosan-metal based complexes. Copyright © 2017. Published by Elsevier B.V.

Who is afraid of math? Two sources of genetic variance for mathematical anxiety.

PubMed

Wang, Zhe; Hart, Sara Ann; Kovas, Yulia; Lukowski, Sarah; Soden, Brooke; Thompson, Lee A; Plomin, Robert; McLoughlin, Grainne; Bartlett, Christopher W; Lyons, Ian M; Petrill, Stephen A

2014-09-01

Emerging work suggests that academic achievement may be influenced by the management of affect as well as through efficient information processing of task demands. In particular, mathematical anxiety has attracted recent attention because of its damaging psychological effects and potential associations with mathematical problem solving and achievement. This study investigated the genetic and environmental factors contributing to the observed differences in the anxiety people feel when confronted with mathematical tasks. In addition, the genetic and environmental mechanisms that link mathematical anxiety with math cognition and general anxiety were also explored. Univariate and multivariate quantitative genetic models were conducted in a sample of 514 12-year-old twin siblings. Genetic factors accounted for roughly 40% of the variation in mathematical anxiety, with the remaining being accounted for by child-specific environmental factors. Multivariate genetic analyses suggested that mathematical anxiety was influenced by the genetic and nonfamilial environmental risk factors associated with general anxiety and additional independent genetic influences associated with math-based problem solving. The development of mathematical anxiety may involve not only exposure to negative experiences with mathematics, but also likely involves genetic risks related to both anxiety and math cognition. These results suggest that integrating cognitive and affective domains may be particularly important for mathematics and may extend to other areas of academic achievement. © 2014 The Authors. Journal of Child Psychology and Psychiatry. © 2014 Association for Child and Adolescent Mental Health.

Factors affecting the energy cost of level running at submaximal speed.

PubMed

Lacour, Jean-René; Bourdin, Muriel

2015-04-01

Metabolic measurement is still the criterion for investigation of the efficiency of mechanical work and for analysis of endurance performance in running. Metabolic demand may be expressed either as the energy spent per unit distance (energy cost of running, C r) or as energy demand at a given running speed (running economy). Systematic studies showed a range of costs of about 20 % between runners. Factors affecting C r include body dimensions: body mass and leg architecture, mostly calcaneal tuberosity length, responsible for 60-80 % of the variability. Children show a higher C r than adults. Higher resting metabolism and lower leg length/stature ratio are the main putative factors responsible for the difference. Elastic energy storage and reuse also contribute to the variability of C r. The increase in C r with increasing running speed due to increase in mechanical work is blunted till 6-7 m s(-1) by the increase in vertical stiffness and the decrease in ground contact time. Fatigue induced by prolonged or intense running is associated with up to 10 % increased C r; the contribution of metabolic and biomechanical factors remains unclear. Women show a C r similar to men of similar body mass, despite differences in gait pattern. The superiority of black African runners is presumably related to their leg architecture and better elastic energy storage and reuse.

Optimization of thiamethoxam adsorption parameters using multi-walled carbon nanotubes by means of fractional factorial design.

PubMed

Panić, Sanja; Rakić, Dušan; Guzsvány, Valéria; Kiss, Erne; Boskovic, Goran; Kónya, Zoltán; Kukovecz, Ákos

2015-12-01

The aim of this work was to evaluate significant factors affecting the thiamethoxam adsorption efficiency using oxidized multi-walled carbon nanotubes (MWCNTs) as adsorbents. Five factors (initial solution concentration of thiamethoxam in water, temperature, solution pH, MWCNTs weight and contact time) were investigated using 2V(5-1) fractional factorial design. The obtained linear model was statistically tested using analysis of variance (ANOVA) and the analysis of residuals was used to investigate the model validity. It was observed that the factors and their second-order interactions affecting the thiamethoxam removal can be divided into three groups: very important, moderately important and insignificant ones. The initial solution concentration was found to be the most influencing parameter on thiamethoxam adsorption from water. Optimization of the factors levels was carried out by minimizing those parameters which are usually critical in real life: the temperature (energy), contact time (money) and weight of MWCNTs (potential health hazard), in order to maximize the adsorbed amount of the pollutant. The results of maximal adsorbed thiamethoxam amount in both real and optimized experiments indicate that among minimized parameters the adsorption time is one that makes the largest difference. The results of this study indicate that fractional factorial design is very useful tool for screening the higher number of parameters and reducing the number of adsorption experiments. Copyright © 2015 Elsevier Ltd. All rights reserved.

Who’s Afraid of Math? Two Sources of Genetic Variance for Mathematical Anxiety

PubMed Central

Wang, Zhe; Hart, Sara Ann; Kovas, Yulia; Lukowski, Sarah; Soden, Brooke; Thompson, Lee A.; Plomin, Robert; McLoughlin, Grainne; Bartlett, Christopher W.; Lyons, Ian M.; Petrill, Stephen A.

2015-01-01

Background Emerging work suggests that academic achievement may be influenced by the management of affect as well as through efficient information processing of task demands. In particular, mathematical anxiety has attracted recent attention because of its damaging psychological effects and potential associations with mathematical problem-solving and achievement. The present study investigated the genetic and environmental factors contributing to the observed differences in the anxiety people feel when confronted with mathematical tasks. In addition, the genetic and environmental mechanisms that link mathematical anxiety with math cognition and general anxiety were also explored. Methods Univariate and multivariate quantitative genetic models were conducted in a sample of 514 12-year-old twin siblings. Results Genetic factors accounted for roughly 40% of the variation in mathematical anxiety, with the remaining being accounted for by child-specific environmental factors. Multivariate genetic analyses suggested that mathematical anxiety was influenced by the genetic and non-familial environmental risk factors associated with general anxiety and additional independent genetic influences associated with math-based problem solving. Conclusions The development of mathematical anxiety may involve not only exposure to negative experiences with mathematics, but also likely involves genetic risks related to both anxiety and math cognition. These results suggest that integrating cognitive and affective domains may be particularly important for mathematics, and may extend to other areas of academic achievement. PMID:24611799

Platelet-Derived Short-Chain Polyphosphates Enhance the Inactivation of Tissue Factor Pathway Inhibitor by Activated Coagulation Factor XI.

PubMed

Puy, Cristina; Tucker, Erik I; Ivanov, Ivan S; Gailani, David; Smith, Stephanie A; Morrissey, James H; Gruber, András; McCarty, Owen J T

2016-01-01

Factor (F) XI supports both normal human hemostasis and pathological thrombosis. Activated FXI (FXIa) promotes thrombin generation by enzymatic activation of FXI, FIX, FX, and FV, and inactivation of alpha tissue factor pathway inhibitor (TFPIα), in vitro. Some of these reactions are now known to be enhanced by short-chain polyphosphates (SCP) derived from activated platelets. These SCPs act as a cofactor for the activation of FXI and FV by thrombin and FXIa, respectively. Since SCPs have been shown to inhibit the anticoagulant function of TFPIα, we herein investigated whether SCPs could serve as cofactors for the proteolytic inactivation of TFPIα by FXIa, further promoting the efficiency of the extrinsic pathway of coagulation to generate thrombin. Purified soluble SCP was prepared by size-fractionation of sodium polyphosphate. TFPIα proteolysis was analyzed by western blot. TFPIα activity was measured as inhibition of FX activation and activity in coagulation and chromogenic assays. SCPs significantly accelerated the rate of inactivation of TFPIα by FXIa in both purified systems and in recalcified plasma. Moreover, platelet-derived SCP accelerated the rate of inactivation of platelet-derived TFPIα by FXIa. TFPIα activity was not affected by SCP in recalcified FXI-depleted plasma. Our data suggest that SCP is a cofactor for TFPIα inactivation by FXIa, thus, expanding the range of hemostatic FXIa substrates that may be affected by the cofactor functions of platelet-derived SCP.

TGF-β Negatively Regulates Mitf-E Expression and Canine Osteoclastogenesis.

PubMed

Asai, Kumiko; Hisasue, Masaharu; Shimokawa, Fumie; Funaba, Masayuki; Murakami, Masaru

2018-04-21

With longevity, the prevalence of osteoporosis, which occurs when the activity of osteoclast surpasses that of osteoblasts, has increased in dogs. However, limited information is available on canine osteoclastogenesis. We herein described culture conditions to induce osteoclasts from canine bone marrow cells, and identified factors affecting canine osteoclastogenesis. Tartrate-resistant acid phosphatase-positive multinucleated cells were efficiently formed in a culture of bone marrow mononuclear cells with macrophage colony-stimulating factor (M-CSF 25 ng/mL) for 3 days and a subsequent culture in the presence of M-CSF (25 ng/mL) and soluble receptor activator of NF-κB ligand (RANKL 50 ng/mL) for 4 days. We previously reported in a murine cell system that gene induction of the E isoform of microphthalmia-associated transcription factor (Mitf-E) was required and sufficient for osteoclastogenesis, while transforming growth factor-β (TGF-β) enhanced RANKL-induced Mitf-E expression and osteoclastogenesis. Mitf-E expression also increased during RANKL-induced osteoclastogenesis in canine cells; however, TGF-β down-regulated Mitf-E expression and osteoclastogenesis, indicating a species-dependent response. The results of the present study show that, consistent with murine cells, M-CSF and soluble RANKL enable canine bone marrow cells to differentiate into osteoclasts, and Mitf-E expression is induced during osteoclastogenesis. However, the role of TGF-β in osteoclast formation is distinct between murine and canine cells, suggesting the necessity of analyses using canine cells to examine the factors affecting canine osteoclastogenesis.

Selecting a provider: what factors influence patients' decision making?

PubMed

Abraham, Jean; Sick, Brian; Anderson, Joseph; Berg, Andrea; Dehmer, Chad; Tufano, Amanda

2011-01-01

Each year consumers make a variety of decisions relating to their healthcare. Some experts argue that stronger consumer engagement in decisions about where to obtain medical care is an important mechanism for improving efficiency in healthcare delivery and financing. Consumers' ability and motivation to become more active decision makers are affected by several factors, including financial incentives and access to information. This study investigates the set of factors that consumers consider when selecting a provider, including attributes of the provider and the care experience and the reputation of the provider. Additionally, the study evaluates consumers awareness and use of formal sources of provider selection information. Our results from analyzing data from a survey of 467 patients at four clinics in Minnesota suggest that the factors considered of greatest importance include reputation of the physician and reputation of the healthcare organization. Contractual and logistical factors also play a role, with respondents highlighting the importance of seeing a provider affiliated with their health plan and appointment availability. Few respondents indicated that advertisements or formal sources of quality information affected their decision making. The key implication for provider organizations is to carefully manage referral sources to ensure that they consistently meet the needs of referrers. Excellent service to existing patients and to the network of referring physicians yields patient and referrer satisfaction that is critical to attracting new patients. Finally, organizations more generally may want to explore the capabilities of new media and social networking sites for building reputation.

Variants in the 3' UTR of General Transcription Factor IIF, polypeptide 2 affect female calving efficiency in Japanese Black cattle

PubMed Central

2013-01-01

Background Calving efficiency can be described as the measure of a cow’s ability to produce viable offspring within a specific period of time. This trait is crucial in beef cattle because calves are necessary both for the production of beef and for heifer replacements. Recently, the number of calves produced at 4 years of age (NCP4) has been used to evaluate the calving efficiency of Japanese Black cattle. To identify variants associated with calving efficiency in Japanese Black cattle, we conducted a genome-wide association study (GWAS) using 688 animals with extreme NCP4 values selected from 15,225 animals. Results We identified genetic variants on bovine chromosome 12 (BTA12) that were associated with NCP4. The General Transcription Factor IIF, polypeptide 2 (GTF2F2), located in the 132 kbp-associated region, proved to be in strong linkage disequilibrium. We found 15 associated variants in the promoter and the 3' UTR regions. Consistent with this finding, transcripts of GTF2F2 derived from the haplotype (Q) with the increased number of calves were 1.33-fold more abundant than q-derived transcripts. Furthermore, luciferase assays revealed that the activity of the 3' UTR, a region that includes nine SNPs, was higher in constructs with the Q haplotype than in those with the q haplotype by approximately 1.35-fold. In contrast, the activity of the promoter region did not differ between haplotypes. The association was replicated in an independent sample of 827 animals that were randomly selected from the remainder of the cohort from the same farms used in the GWAS. In the replicated population, the frequency of the Q haplotype is 0.313, and this haplotype accounts for 2.69% of the total phenotypic variance. The effect of the Q to q haplotype substitution on NCP4 was 0.054 calves. These findings suggest that variants in the 3' UTR of GTF2F2 affect the level of GTF2F2 mRNA, which is associated with calving efficiency. Conclusions This GWAS has identified variants in the 3’ UTR of GTF2F2 that were associated with the NCP4 of Japanese Black cattle, and this association was validated in an independent sample. The Q haplotype will be immediately useful in improving the calving efficiency of Japanese Black cattle. PMID:23663537

Application of acoustic agglomeration to enhance air filtration efficiency in air-conditioning and mechanical ventilation (ACMV) systems.

PubMed

Ng, Bing Feng; Xiong, Jin Wen; Wan, Man Pun

2017-01-01

The recent episodes of haze in Southeast Asia have caused some of the worst regional atmospheric pollution ever recorded in history. In order to control the levels of airborne fine particulate matters (PM) indoors, filtration systems providing high PM capturing efficiency are often sought, which inadvertently also results in high airflow resistance (or pressure drop) that increases the energy consumption for air distribution. A pre-conditioning mechanism promoting the formation of particle clusters to enhance PM capturing efficiency without adding flow resistance in the air distribution ductwork could provide an energy-efficient solution. This pre-conditioning mechanism can be fulfilled by acoustic agglomeration, which is a phenomenon that promotes the coagulation of suspended particles by acoustic waves propagating in the fluid medium. This paper discusses the basic mechanisms of acoustic agglomeration along with influencing factors that could affect the agglomeration efficiency. The feasibility to apply acoustic agglomeration to improve filtration in air-conditioning and mechanical ventilation (ACMV) systems is investigated experimentally in a small-scale wind tunnel. Experimental results indicate that this novel application of acoustic pre-conditioning improves the PM2.5 filtration efficiency of the test filters by up to 10% without introducing additional pressure drop. The fan energy savings from not having to switch to a high capturing efficiency filter largely outstrip the additional energy consumed by the acoustics system. This, as a whole, demonstrates potential energy savings from the combined acoustic-enhanced filtration system without compromising on PM capturing efficiency.

Application of acoustic agglomeration to enhance air filtration efficiency in air-conditioning and mechanical ventilation (ACMV) systems

PubMed Central

Xiong, Jin Wen; Wan, Man Pun

2017-01-01

The recent episodes of haze in Southeast Asia have caused some of the worst regional atmospheric pollution ever recorded in history. In order to control the levels of airborne fine particulate matters (PM) indoors, filtration systems providing high PM capturing efficiency are often sought, which inadvertently also results in high airflow resistance (or pressure drop) that increases the energy consumption for air distribution. A pre-conditioning mechanism promoting the formation of particle clusters to enhance PM capturing efficiency without adding flow resistance in the air distribution ductwork could provide an energy-efficient solution. This pre-conditioning mechanism can be fulfilled by acoustic agglomeration, which is a phenomenon that promotes the coagulation of suspended particles by acoustic waves propagating in the fluid medium. This paper discusses the basic mechanisms of acoustic agglomeration along with influencing factors that could affect the agglomeration efficiency. The feasibility to apply acoustic agglomeration to improve filtration in air-conditioning and mechanical ventilation (ACMV) systems is investigated experimentally in a small-scale wind tunnel. Experimental results indicate that this novel application of acoustic pre-conditioning improves the PM2.5 filtration efficiency of the test filters by up to 10% without introducing additional pressure drop. The fan energy savings from not having to switch to a high capturing efficiency filter largely outstrip the additional energy consumed by the acoustics system. This, as a whole, demonstrates potential energy savings from the combined acoustic-enhanced filtration system without compromising on PM capturing efficiency. PMID:28594862

The efficiency of genome-wide selection for genetic improvement of net merit.

PubMed

Togashi, K; Lin, C Y; Yamazaki, T

2011-10-01

Four methods of selection for net merit comprising 2 correlated traits were compared in this study: 1) EBV-only index (I₁), which consists of the EBV of both traits (i.e., traditional 2-trait BLUP selection); 2) GEBV-only index (I₂), which comprises the genomic EBV (GEBV) of both traits; 3) GEBV-assisted index (I₃), which combines both the EBV and the GEBV of both traits; and 4) GBV-assisted index (I₄), which combines both the EBV and the true genomic breeding value (GBV) of both traits. Comparisons of these indices were based on 3 evaluation criteria [selection accuracy, genetic response (ΔH), and relative efficiency] under 64 scenarios that arise from combining 2 levels of genetic correlation (r(G)), 2 ratios of genetic variances between traits, 2 ratios of the genomic variance to total genetic variances for trait 1, 4 accuracies of EBV, and 2 proportions of r(G) explained by the GBV. Both selection accuracy and genetic responses of the indices I₁, I₃, and I₄ increased as the accuracy of EBV increased, but the efficiency of the indices I₃ and I₄ relative to I₁ decreased as the accuracy of EBV increased. The relative efficiency of both I₃ and I₄ was generally greater when the accuracy of EBV was 0.6 than when it was 0.9, suggesting that the genomic markers are most useful to assist selection when the accuracy of EBV is low. The GBV-assisted index I₄ was superior to the GEBV-assisted I₃ in all 64 cases examined, indicating the importance of improving the accuracy of prediction of genomic breeding values. Other parameters being identical, increasing the genetic variance of a high heritability trait would increase the genetic response of the genomic indices (I₂, I₃, and I₄). The genetic responses to I₂, I₃, and I(4) was greater when the genetic correlation between traits was positive (r(G) = 0.5) than when it was negative (r(G) = -0.5). The results of this study indicate that the effectiveness of the GEBV-assisted index I₃ is affected by heritability of and genetic correlation between traits, the ratio of genetic variances between traits, the genomic-genetic variance ratio of each index trait, the proportion of genetic correlation accounted for by the genomic markers, and the accuracy of predictions of both EBV and GBV. However, most of these affecting factors are genetic characteristics of a population that is beyond the control of the breeders. The key factor subject to manipulation is to maximize both the proportion of the genetic variance explained by GEBV and the accuracy of both GEBV and EBV. The developed procedures provide means to investigate the efficiency of various genomic indices for any given combination of the genetic factors studied.

Technical- and environmental-efficiency analysis of irrigated cotton-cropping systems in Punjab, Pakistan using data envelopment analysis.

PubMed

Ullah, Asmat; Perret, Sylvain R

2014-08-01

Cotton cropping in Pakistan uses substantial quantities of resources and adversely affects the environment with pollutants from the inputs, particularly pesticides. A question remains regarding to what extent the reduction of such environmental impact is possible without compromising the farmers' income. This paper investigates the environmental, technical, and economic performances of selected irrigated cotton-cropping systems in Punjab to quantify the sustainability of cotton farming and reveal options for improvement. Using mostly primary data, our study quantifies the technical, cost, and environmental efficiencies of different farm sizes. A set of indicators has been computed to reflect these three domains of efficiency using the data envelopment analysis technique. The results indicate that farmers are broadly environmentally inefficient; which primarily results from poor technical inefficiency. Based on an improved input mix, the average potential environmental impact reduction for small, medium, and large farms is 9, 13, and 11 %, respectively, without compromising the economic return. Moreover, the differences in technical, cost, and environmental efficiencies between small and medium and small and large farm sizes were statistically significant. The second-stage regression analysis identifies that the entire farm size significantly affects the efficiencies, whereas exposure to extension and training has positive effects, and the sowing methods significantly affect the technical and environmental efficiencies. Paradoxically, the formal education level is determined to affect the efficiencies negatively. This paper discusses policy interventions that can improve the technical efficiency to ultimately increase the environmental efficiency and reduce the farmers' operating costs.

Documentation of incidental factors affecting the home healthcare work environment.

PubMed

Sitzman, Kathleen L; Leiss, Jack K

2009-10-01

Working conditions related to unrestrained pets, unruly children, clutter, and poor lighting during home healthcare visits are considered normal aspects of care providers' jobs. To date, there has been no documentation related to how often these factors are present in the home healthcare setting during home visits. In this study, 833 home healthcare nurses practicing in North Carolina answered a questionnaire that included items related to how often unrestrained pets, unruly children, poor lighting, and clutter existed in the homes they visited. Results showed that one-third to one-half of the respondents usually or always visited homes with unrestrained pets, clutter, or poor lighting and few nurses usually or always visited homes with uncontrolled children. Better understanding of the prevalence of these factors will facilitate further study related to their effects on safety, efficiency, and job satisfaction for home healthcare workers.

Direct reprogramming and biomaterials for controlling cell fate.

PubMed

Kim, Eunsol; Tae, Giyoong

2016-01-01

Direct reprogramming which changes the fate of matured cell is a very useful technique with a great interest recently. This approach can eliminate the drawbacks of direct usage of stem cells and allow the patient specific treatment in regenerative medicine. Overexpression of diverse factors such as general reprogramming factors or lineage specific transcription factors can change the fate of already differentiated cells. On the other hand, biomaterials can provide physical and topographical cues or biochemical cues on cells, which can dictate or significantly affect the differentiation of stem cells. The role of biomaterials on direct reprogramming has not been elucidated much, but will be potentially significant to improve the efficiency or specificity of direct reprogramming. In this review, the strategies for general direct reprogramming and biomaterials-guided stem cell differentiation are summarized with the addition of the up-to-date progress on biomaterials for direct reprogramming.

Barriers to Practical Learning in the Field: A Qualitative Study of Iranian Nursing Students' Experiences.

PubMed

Jahanpour, Faezeh; Azodi, Parviz; Azodi, Farzan; Khansir, Ali Akbar

2016-06-01

Clinical training is an integral part of nursing education; however, some studies have shown that it is not always efficient. This study aimed to find out the factors that can impede nursing students' clinical learning. In this qualitative study, data were collected via reflective journal writing. Purposeful sampling was used, and 12 senior nursing students were recruited to the study. The data were analyzed using a content analysis method. Three main categories were derived, including inappropriate communication, ineffective role models, and theory-practice gaps. Students perceived that inappropriate communication between instructors, staff members, and students had the greatest impact on student learning. The competence of clinical instructors and staff is an important factor affecting students' training. The clinical learning environment does not always integrate theory and practice together. Nursing students did not experience effective clinical learning. Having expert instructors and supportive communication are important factors in creating a clinical learning environment.

Human factors of the high technology cockpit

NASA Technical Reports Server (NTRS)

Wiener, Earl L.

1990-01-01

The rapid advance of cockpit automation in the last decade has outstripped the ability of the human factors profession to understand the changes in human functions required. High technology cockpits require less physical (observable) workload, but are highly demanding of cognitive functions such as planning, alternative selection, and monitoring. Furthermore, automation creates opportunity for new and more serious forms of human error, and many pilots are concerned about the possibility of complacency affecting their performance. On the positive side, the equipment works as advertized with high reliability, offering highly efficient, computer-based flight. These findings from the cockpit studies probably apply equally to other industries, such as nuclear power production, other modes of transportation, medicine, and manufacturing, all of which traditionally have looked to aviation for technological leadership. The challenge to the human factors profession is to aid designers, operators, and training departments in exploiting the positive side of automation, while seeking solutions to the negative side. Viewgraphs are given.

A historical analysis of the co-evolution of gasoline octane number and spark-ignition engines

DOE PAGES

Splitter, Derek A.; Pawlowski, Alex E.; Wagner, Robert M.

2016-01-06

In our work, the authors reviewed engine, vehicle, and fuel data since 1925 to examine the historical and recent coupling of compression ratio and fuel antiknock properties (i.e., octane number) in the U.S. light-duty vehicle market. The analysis identified historical timeframes, trends, and illustrated how three factors: consumer preferences, technical capabilities, and regulatory legislation, affect personal mobility. Data showed that throughout history these three factors have a complex and time sensitive interplay. Long term trends in the data were identified where interaction and evolution between all three factors was observed. Transportation efficiency per unit power (gal/ton-mi/hp) was found to bemore » a good metric to integrate technical, societal, and regulatory effects into the evolutional pathway of personal mobility. From this framework, discussions of future evolutionary changes to personal mobility are also presented.« less

The optimization of design parameters for surge relief valve for pipeline systems

NASA Astrophysics Data System (ADS)

Kim, Hyunjun; Hur, Jisung; Kim, Sanghyun

2017-06-01

Surge is an abnormal pressure which induced by rapid changes of flow rate in pipeline systems. In order to protect pipeline system from the surge pressure, various hydraulic devices have been developed. Surge-relief valve(SRV) is one of the widely applied devices to control surge due to its feasibility in application, efficiency and cost-effectiveness. SRV is designed to automatically open under abnormal pressure and discharge the flow and makes pressure of the system drop to the allowable level. The performance of the SRV is influenced by hydraulics. According to previous studies, there are several affecting factors which determine performance of the PRV such as design parameters (e.g. size of the valve), system parameters (e.g. number of the valves and location of the valve), and operation parameters (e.g. set point and operation time). Therefore, the systematic consideration for factors affecting performance of SRV is required for the proper installation of SRV in the system. In this study, methodology for finding optimum parameters of the SRV is explored through the integration of Genetic Algorithm(GA) into surge analysis.

Neuroanatomical and Cognitive Mediators of Age-Related Differences in Episodic Memory

PubMed Central

Head, Denise; Rodrigue, Karen M.; Kennedy, Kristen M.; Raz, Naftali

2009-01-01

Aging is associated with declines in episodic memory. In this study, the authors used a path analysis framework to explore the mediating role of differences in brain structure, executive functions, and processing speed in age-related differences in episodic memory. Measures of regional brain volume (prefrontal gray and white matter, caudate, hippocampus, visual cortex), executive functions (working memory, inhibitory control, task switching, temporal processing), processing speed, and episodic memory were obtained in a sample of young and older adults. As expected, age was linked to reduction in regional brain volumes and cognitive performance. Moreover, neural and cognitive factors completely mediated age differences in episodic memory. Whereas hippocampal shrinkage directly affected episodic memory, prefrontal volumetric reductions influenced episodic memory via limitations in working memory and inhibitory control. Age-related slowing predicted reduced efficiency in temporal processing, working memory, and inhibitory control. Lastly, poorer temporal processing directly affected episodic memory. No direct effects of age on episodic memory remained once these factors were taken into account. These analyses highlight the value of a multivariate approach with the understanding of complex relationships in cognitive and brain aging. PMID:18590361

Factors Affecting Domestic Water Consumption in Rural Households upon Access to Improved Water Supply: Insights from the Wei River Basin, China

PubMed Central

Fan, Liangxin; Liu, Guobin; Wang, Fei; Geissen, Violette; Ritsema, Coen J.

2013-01-01

Comprehensively understanding water consumption behavior is necessary to design efficient and effective water use strategies. Despite global efforts to identify the factors that affect domestic water consumption, those related to domestic water use in rural regions have not been sufficiently studied, particularly in villages that have gained access to improved water supply. To address this gap, we investigated 247 households in eight villages in the Wei River Basin where three types of improved water supply systems are implemented. Results show that domestic water consumption in liters per capita per day was significantly correlated with water supply pattern and vegetable garden area, and significantly negatively correlated with family size and age of household head. Traditional hygiene habits, use of water appliances, and preference for vegetable gardening remain dominant behaviors in the villages with access to improved water supply. Future studies on rural domestic water consumption should pay more attention to user lifestyles (water appliance usage habits, outdoor water use) and cultural backgrounds (age, education). PMID:23977190

Factors affecting domestic water consumption in rural households upon access to improved water supply: insights from the Wei River Basin, China.

PubMed

Fan, Liangxin; Liu, Guobin; Wang, Fei; Geissen, Violette; Ritsema, Coen J

2013-01-01

Comprehensively understanding water consumption behavior is necessary to design efficient and effective water use strategies. Despite global efforts to identify the factors that affect domestic water consumption, those related to domestic water use in rural regions have not been sufficiently studied, particularly in villages that have gained access to improved water supply. To address this gap, we investigated 247 households in eight villages in the Wei River Basin where three types of improved water supply systems are implemented. Results show that domestic water consumption in liters per capita per day was significantly correlated with water supply pattern and vegetable garden area, and significantly negatively correlated with family size and age of household head. Traditional hygiene habits, use of water appliances, and preference for vegetable gardening remain dominant behaviors in the villages with access to improved water supply. Future studies on rural domestic water consumption should pay more attention to user lifestyles (water appliance usage habits, outdoor water use) and cultural backgrounds (age, education).

Driving and dementia: Efficient approach to driving safety concerns in family practice.

PubMed

Lee, Linda; Molnar, Frank

2017-01-01

To provide primary care physicians with an approach to driving safety concerns when older persons present with memory difficulties. The approach is based on an accredited memory clinic training program developed by the Centre for Family Medicine Primary Care Collaborative Memory Clinic. One of the most challenging aspects of dementia care is the assessment of driving safety. Drivers with dementia are at higher risk of motor vehicle collisions, yet many drivers with mild dementia might be safely able to continue driving for several years. Because safe driving is dependent on multiple cognitive and functional skills, clinicians should carefully consider many factors when determining if cognitive concerns affect driving safety. Specific findings on corroborated history and office-based cognitive testing might aid in the physician's decisions to refer for comprehensive on-road driving evaluation and whether to notify transportation authorities in accordance with provincial reporting requirements. Sensitive communication and a person-centred approach are essential. Primary care physicians must consider many factors when determining if cognitive concerns might affect driving safety in older drivers. Copyright© the College of Family Physicians of Canada.

Dynamics of the microbial community during continuous methane fermentation in continuously stirred tank reactors.

PubMed

Tang, Yue-Qin; Shigematsu, Toru; Morimura, Shigeru; Kida, Kenji

2015-04-01

Methane fermentation is an attractive technology for the treatment of organic wastes and wastewaters. However, the process is difficult to control, and treatment rates and digestion efficiency require further optimization. Understanding the microbiology mechanisms of methane fermentation is of fundamental importance to improving this process. In this review, we summarize the dynamics of microbial communities in methane fermentation chemostats that are operated using completely stirred tank reactors (CSTRs). Each chemostat was supplied with one substrate as the sole carbon source. The substrates include acetate, propionate, butyrate, long-chain fatty acids, glycerol, protein, glucose, and starch. These carbon sources are general substrates and intermediates of methane fermentation. The factors that affect the structure of the microbial community are discussed. The carbon source, the final product, and the operation conditions appear to be the main factors that affect methane fermentation and determine the structure of the microbial community. Understanding the structure of the microbial community during methane fermentation will guide the design and operation of practical wastewater treatments. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matusik, Katarzyna E.; Duke, Daniel J.; Kastengren, Alan L.

The sparking behavior in an internal combustion engine affects the fuel efficiency, engine-out emissions, and general drivability of a vehicle. As emissions regulations become progressively stringent, combustion strategies, including exhaust gas recirculation (EGR), lean-burn, and turbocharging are receiving increasing attention as models of higher efficiency advanced combustion engines with reduced emissions levels. Because these new strategies affect the working environment of the spark plug, ongoing research strives to understand the influence of external factors on the spark ignition process. Due to the short time and length scales involved and the harsh environment, experimental quantification of the deposited energy from themore » sparking event is difficult to obtain. We present the results of x-ray radiography measurements of spark ignition plasma generated by a conventional spark plug. Our measurements were performed at the 7-BM beamline of the Advanced Photon Source at Argonne National Laboratory. The synchrotron x-ray source enables time-resolved measurements of the density change due to glow discharge in the spark gap with 153 ns temporal and 5 μm spatial resolutions. We also explore the effects of charging time, EGR-relevant gas compositions, and gas pressure on the sparking behavior. We also quantify the influence of the measurement technique on the obtained results.« less

Modeling filtration and fouling with a microstructured membrane filter

NASA Astrophysics Data System (ADS)

Cummings, Linda; Sanaei, Pejman

2017-11-01

Membrane filters find widespread use in diverse applications such as A/C systems and water purification. While the details of the filtration process may vary significantly, the broad challenge of efficient filtration is the same: to achieve finely-controlled separation at low power consumption. The obvious resolution to the challenge would appear simple: use the largest pore size consistent with the separation requirement. However, the membrane characteristics (and hence the filter performance) are far from constant over its lifetime: the particles removed from the feed are deposited within and on the membrane filter, fouling it and degrading the performance over time. The processes by which this occurs are complex, and depend on several factors, including: the internal structure of the membrane and the type of particles in the feed. We present a model for fouling of a simple microstructured membrane, and investigate how the details of the microstructure affect the filtration efficiency. Our idealized membrane consists of bifurcating pores, arranged in a layered structure, so that the number (and size) of pores changes in the depth of the membrane. In particular, we address how the details of the membrane microstructure affect the filter lifetime, and the total throughput. NSF DMS 1615719.

Comparison of placental traits and their relation to litter size and parity weight in sheep.

PubMed

Ocak, S; Emsen, E; Köycegiz, F; Kutluca, M; Onder, H

2009-10-01

The relationships between genotype and placental traits, parity and litter weight (LW), and factors affecting these characteristics were investigated in this study. In total, 112 ewes (Romanov crossbred and local breeds) were utilized. One-way ANOVA was used for statistical comparison, and a Pearson correlation was used to determine the relationships between the variables. Significant differences in parity weight within genotype and breed have been determined. A negative correlation was revealed between placental weight (PW) and placental efficiency (r = -0.743, P < 0.01; and r = -0.732, P < 0.01). There was no relationship between litter sex and placental traits. Birth type had a significant effect on PW (P < 0.05), and significant differences within sex-birth type interactions occurred (P < 0.05). The results of the present study have shown a positive correlation between cotyledon density and placental efficiency among all genotypes and breeds that were used in the study. In conclusion, it has been determined that placental traits were affected by LW and Romanov crossbreed ewes had greater PW than local breeds. Further studies are required to investigate the relationship between parity and placental traits in sheep.

Effect of Material Composition and Environmental Condition on Thermal Characteristics of Conductive Asphalt Concrete.

PubMed

Pan, Pan; Wu, Shaopeng; Hu, Xiaodi; Liu, Gang; Li, Bo

2017-02-23

Conductive asphalt concrete with high thermal conductivity has been proposed to improve the solar energy collection and snow melting efficiencies of asphalt solar collector (ASC). This paper aims to provide some insight into choosing the basic materials for preparation of conductive asphalt concrete, as well as determining the evolution of thermal characteristics affected by environmental factors. The thermal properties of conductive asphalt concrete were studied by the Thermal Constants Analyzer. Experimental results showed that aggregate and conductive filler have a significant effect on the thermal properties of asphalt concrete, while the effect of asphalt binder was not evident due to its low proportion. Utilization of mineral aggregate and conductive filler with higher thermal conductivity is an efficient method to prepare conductive asphalt concrete. Moreover, change in thermal properties of asphalt concrete under different temperature and moisture conditions should be taken into account to determine the actual thermal properties of asphalt concrete. There was no noticeable difference in thermal properties of asphalt concrete before and after aging. Furthermore, freezing-thawing cycles strongly affect the thermal properties of conductive asphalt concrete, due to volume expansion and bonding degradation.

Effect of Material Composition and Environmental Condition on Thermal Characteristics of Conductive Asphalt Concrete

PubMed Central

Pan, Pan; Wu, Shaopeng; Hu, Xiaodi; Liu, Gang; Li, Bo

2017-01-01

Conductive asphalt concrete with high thermal conductivity has been proposed to improve the solar energy collection and snow melting efficiencies of asphalt solar collector (ASC). This paper aims to provide some insight into choosing the basic materials for preparation of conductive asphalt concrete, as well as determining the evolution of thermal characteristics affected by environmental factors. The thermal properties of conductive asphalt concrete were studied by the Thermal Constants Analyzer. Experimental results showed that aggregate and conductive filler have a significant effect on the thermal properties of asphalt concrete, while the effect of asphalt binder was not evident due to its low proportion. Utilization of mineral aggregate and conductive filler with higher thermal conductivity is an efficient method to prepare conductive asphalt concrete. Moreover, change in thermal properties of asphalt concrete under different temperature and moisture conditions should be taken into account to determine the actual thermal properties of asphalt concrete. There was no noticeable difference in thermal properties of asphalt concrete before and after aging. Furthermore, freezing–thawing cycles strongly affect the thermal properties of conductive asphalt concrete, due to volume expansion and bonding degradation. PMID:28772580

Organogenesis from transformed tomato explants.

PubMed

Frary, Anne; Van Eck, Joyce

2005-01-01

Tomato was one of the first crops for which a genetic transformation system was reported involving regeneration by organogenesis from Agrobacterium-transformed explants. Since the initial reports, various factors have been studied that affect the efficiency of tomato transformation and the technique has been useful for the isolation and identification of many genes involved in plant disease resistance, morphology and development. In this method, cotyledon explants from in vitro-grown seedlings are precultured overnight on a tobacco suspension feeder layer. The explants are then inoculated with Agrobacterium and returned to the feeder layer for a 2-d period of cocultivation. After cocultivation, the explants are transferred to an MS-based selective regeneration medium containing zeatin. Regenerated shoots are then rooted on a separate selective medium. This protocol has been used with several tomato cultivars and routinely yields transformation efficiencies of 10-15%.

Biopolymer system for permeability modification in porous media

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stepp, A.K.; Bryant, R.S.; Llave, F.M.

1995-12-31

New technologies are needed to reduce the current high rate of well abandonment. Improved sweep efficiency, reservoir conformance, and permeability modification can have a significant impact on oil recovery processes. Microorganisms can be used to selectively plug high-permeability zones to improve sweep efficiency and impart conformance control. Studies of a promising microbial system for polymer production were conducted to evaluate reservoir conditions in which this system would be effective. Factors which can affect microbial growth and polymer production include salinity, pH, temperature, divalent ions, presence of residual oil, and rock matrix. Flask tests and coreflooding experiments were conducted to optimizemore » and evaluate the effectiveness of this system. Nuclear magnetic resonance imaging (NMRI) was used to visualize microbial polymer production in porous media. Changes in fluid distribution within the pore system of the core were detected.« less

Research on optimization of combustion efficiency of thermal power unit based on genetic algorithm

NASA Astrophysics Data System (ADS)

Zhou, Qiongyang

2018-04-01

In order to improve the economic performance and reduce pollutant emissions of thermal power units, the characteristics of neural network in establishing boiler combustion model are analyzed based on the analysis of the main factors affecting boiler efficiency by using orthogonal method. In addition, on the basis of this model, the genetic algorithm is used to find the best control amount of the furnace combustion in a certain working condition. Through the genetic algorithm based on real number encoding and roulette selection is concluded: the best control quantity at a condition of furnace combustion can be combined with the boiler combustion system model for neural network training. The precision of the neural network model is further improved, and the basic work is laid for the research of the whole boiler combustion optimization system.

Experimental Design for a Macrofoam Swab Study Relating the Recovery Efficiency and False Negative Rate to Low Concentrations of Two Bacillus anthracis Surrogates on Four Surface Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piepel, Gregory F.; Hutchison, Janine R.

2014-04-16

This report describes the experimental design for a laboratory study to quantify the recovery efficiencies and false negative rates of a validated, macrofoam swab sampling method for low concentrations of Bacillus anthracis Sterne (BAS) and Bacillus atrophaeus (BG) spores on four surface materials (stainless steel, glass, vinyl tile, plastic light cover panel). Two analytical methods (plating/counting and polymerase chain reaction) will be used. Only one previous study has investigated false negative as a function of affecting test factors. The surrogates BAS and BG have not been tested together in the same study previously. Hence, this study will provide for completingmore » gaps in the available information on the performance of macrofoam swab sampling at low concentrations.« less

Factors affecting the photoproduction of ammonia from dinitrogen and water by the cyanobacterium Anabaena sp. strain ATCC 33047.

PubMed

Ramos, J L; Guerrero, M G; Losada, M

1987-04-01

Synthesis of ammonia from dinitrogen and water by suspensions of Anabaena sp. Strain ATCC 33047 treated with the glutamine synthetase inhibitor L-methionine-D,L-sulfoximine is strictly dependent on light. Under otherwise optimal conditions, the yield of ammonia production is influenced by irradiance, as well as by the density, depth, and turbulence of the cell suspension. The interaction among these factors seems to determine the actual amount of light available to each single cell or filament in the suspension for the photoproduction process. Under convenient illumination, the limiting factor in the synthesis of ammonia seems to be the cellular nitrogenase activity level, but under limiting light conditions the limiting factor could, however, be the assimilatory power required for nitrogen fixation. Photosynthetic ammonia production from atmospheric nitrogen and water can operate with an efficiency of ca. 10% of its theoretical maximum, representing a remarkable process for the conversion of light energy into chemical energy.

Internal quantum efficiency enhancement of GaInN/GaN quantum-well structures using Ag nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iida, Daisuke; Department of Photonics Engineering, Technical University of Denmark, 2800 Lyngby; Faculty of Science and Technology, Meijo University, 1-501 Shiogamaguchi Tempaku, 468-8502 Nagoya

2015-09-15

We report internal quantum efficiency enhancement of thin p-GaN green quantum-well structure using self-assembled Ag nanoparticles. Temperature dependent photoluminescence measurements are conducted to determine the internal quantum efficiency. The impact of excitation power density on the enhancement factor is investigated. We obtain an internal quantum efficiency enhancement by a factor of 2.3 at 756 W/cm{sup 2}, and a factor of 8.1 at 1 W/cm{sup 2}. A Purcell enhancement up to a factor of 26 is estimated by fitting the experimental results to a theoretical model for the efficiency enhancement factor.

Efficiently Identifying Significant Associations in Genome-wide Association Studies

PubMed Central

Eskin, Eleazar

2013-01-01

Abstract Over the past several years, genome-wide association studies (GWAS) have implicated hundreds of genes in common disease. More recently, the GWAS approach has been utilized to identify regions of the genome that harbor variation affecting gene expression or expression quantitative trait loci (eQTLs). Unlike GWAS applied to clinical traits, where only a handful of phenotypes are analyzed per study, in eQTL studies, tens of thousands of gene expression levels are measured, and the GWAS approach is applied to each gene expression level. This leads to computing billions of statistical tests and requires substantial computational resources, particularly when applying novel statistical methods such as mixed models. We introduce a novel two-stage testing procedure that identifies all of the significant associations more efficiently than testing all the single nucleotide polymorphisms (SNPs). In the first stage, a small number of informative SNPs, or proxies, across the genome are tested. Based on their observed associations, our approach locates the regions that may contain significant SNPs and only tests additional SNPs from those regions. We show through simulations and analysis of real GWAS datasets that the proposed two-stage procedure increases the computational speed by a factor of 10. Additionally, efficient implementation of our software increases the computational speed relative to the state-of-the-art testing approaches by a factor of 75. PMID:24033261

Erratum: Probabilistic application of a fugacity model to predict triclosan fate during wastewater treatment.

PubMed

Bock, Michael; Lyndall, Jennifer; Barber, Timothy; Fuchsman, Phyllis; Perruchon, Elyse; Capdevielle, Marie

2010-10-01

The fate and partitioning of the antimicrobial compound, triclosan, in wastewater treatment plants (WWTPs) is evaluated using a probabilistic fugacity model to predict the range of triclosan concentrations in effluent and secondary biosolids. The WWTP model predicts 84% to 92% triclosan removal, which is within the range of measured removal efficiencies (typically 70% to 98%). Triclosan is predominantly removed by sorption and subsequent settling of organic particulates during primary treatment and by aerobic biodegradation during secondary treatment. Median modeled removal efficiency due to sorption is 40% for all treatment phases and 31% in the primary treatment phase. Median modeled removal efficiency due to biodegradation is 48% for all treatment phases and 44% in the secondary treatment phase. Important factors contributing to variation in predicted triclosan concentrations in effluent and biosolids include influent concentrations, solids concentrations in settling tanks, and factors related to solids retention time. Measured triclosan concentrations in biosolids and non-United States (US) effluent are consistent with model predictions. However, median concentrations in US effluent are over-predicted with this model, suggesting that differences in some aspect of treatment practices not incorporated in the model (e.g., disinfection methods) may affect triclosan removal from effluent. Model applications include predicting changes in environmental loadings associated with new triclosan applications and supporting risk analyses for biosolids-amended land and effluent receiving waters. © 2010 SETAC.

Probabilistic application of a fugacity model to predict triclosan fate during wastewater treatment.

PubMed

Bock, Michael; Lyndall, Jennifer; Barber, Timothy; Fuchsman, Phyllis; Perruchon, Elyse; Capdevielle, Marie

2010-07-01

The fate and partitioning of the antimicrobial compound, triclosan, in wastewater treatment plants (WWTPs) is evaluated using a probabilistic fugacity model to predict the range of triclosan concentrations in effluent and secondary biosolids. The WWTP model predicts 84% to 92% triclosan removal, which is within the range of measured removal efficiencies (typically 70% to 98%). Triclosan is predominantly removed by sorption and subsequent settling of organic particulates during primary treatment and by aerobic biodegradation during secondary treatment. Median modeled removal efficiency due to sorption is 40% for all treatment phases and 31% in the primary treatment phase. Median modeled removal efficiency due to biodegradation is 48% for all treatment phases and 44% in the secondary treatment phase. Important factors contributing to variation in predicted triclosan concentrations in effluent and biosolids include influent concentrations, solids concentrations in settling tanks, and factors related to solids retention time. Measured triclosan concentrations in biosolids and non-United States (US) effluent are consistent with model predictions. However, median concentrations in US effluent are over-predicted with this model, suggesting that differences in some aspect of treatment practices not incorporated in the model (e.g., disinfection methods) may affect triclosan removal from effluent. Model applications include predicting changes in environmental loadings associated with new triclosan applications and supporting risk analyses for biosolids-amended land and effluent receiving waters. (c) 2010 SETAC.

Stochastic Analysis of the Efficiency of a Wireless Power Transfer System Subject to Antenna Variability and Position Uncertainties

PubMed Central

Rossi, Marco; Stockman, Gert-Jan; Rogier, Hendrik; Vande Ginste, Dries

2016-01-01

The efficiency of a wireless power transfer (WPT) system in the radiative near-field is inevitably affected by the variability in the design parameters of the deployed antennas and by uncertainties in their mutual position. Therefore, we propose a stochastic analysis that combines the generalized polynomial chaos (gPC) theory with an efficient model for the interaction between devices in the radiative near-field. This framework enables us to investigate the impact of random effects on the power transfer efficiency (PTE) of a WPT system. More specifically, the WPT system under study consists of a transmitting horn antenna and a receiving textile antenna operating in the Industrial, Scientific and Medical (ISM) band at 2.45 GHz. First, we model the impact of the textile antenna’s variability on the WPT system. Next, we include the position uncertainties of the antennas in the analysis in order to quantify the overall variations in the PTE. The analysis is carried out by means of polynomial-chaos-based macromodels, whereas a Monte Carlo simulation validates the complete technique. It is shown that the proposed approach is very accurate, more flexible and more efficient than a straightforward Monte Carlo analysis, with demonstrated speedup factors up to 2500. PMID:27447632

An efficient in planta transformation of Jatropha curcas (L.) and multiplication of transformed plants through in vivo grafting.

PubMed

Jaganath, Balusamy; Subramanyam, Kondeti; Mayavan, Subramanian; Karthik, Sivabalan; Elayaraja, Dhandapani; Udayakumar, Rajangam; Manickavasagam, Markandan; Ganapathi, Andy

2014-05-01

An efficient and reproducible Agrobacterium-mediated in planta transformation was developed in Jatropha curcas. The various factors affecting J. curcas in planta transformation were optimized, including decapitation, Agrobacterium strain, pin-pricking, vacuum infiltration duration and vacuum pressure. Simple vegetative in vivo cleft grafting method was adopted in the multiplication of transformants without the aid of tissue culture. Among the various parameters evaluated, decapitated plants on pin-pricking and vacuum infiltrated at 250 mmHg for 3 min with the Agrobacterium strain EHA 105 harbouring the binary vector pGA 492 was proved to be efficient in all terms with a transformation efficiency of 62.66%. Transgene integration was evinced by the GUS histochemical analysis, and the GUS positive plants were subjected to grafting. Putatively transformed J. curcas served as "Scion" and the wild type J. curcas plant severed as "Stock". There was no occurrence of graft rejection and the plants were then confirmed by GUS histochemical analysis, polymerase chain reaction (PCR) and Southern hybridization. Genetic stability of the grafted plants was evaluated by using randomly amplified polymorphic DNA (RAPD), marker which showed 100% genetic stability between mother and grafted plants. Thus, an efficient in planta transformation and grafting based multiplication of J. curcas was established.

Stochastic Analysis of the Efficiency of a Wireless Power Transfer System Subject to Antenna Variability and Position Uncertainties.

PubMed

Rossi, Marco; Stockman, Gert-Jan; Rogier, Hendrik; Vande Ginste, Dries

2016-07-19

The efficiency of a wireless power transfer (WPT) system in the radiative near-field is inevitably affected by the variability in the design parameters of the deployed antennas and by uncertainties in their mutual position. Therefore, we propose a stochastic analysis that combines the generalized polynomial chaos (gPC) theory with an efficient model for the interaction between devices in the radiative near-field. This framework enables us to investigate the impact of random effects on the power transfer efficiency (PTE) of a WPT system. More specifically, the WPT system under study consists of a transmitting horn antenna and a receiving textile antenna operating in the Industrial, Scientific and Medical (ISM) band at 2.45 GHz. First, we model the impact of the textile antenna's variability on the WPT system. Next, we include the position uncertainties of the antennas in the analysis in order to quantify the overall variations in the PTE. The analysis is carried out by means of polynomial-chaos-based macromodels, whereas a Monte Carlo simulation validates the complete technique. It is shown that the proposed approach is very accurate, more flexible and more efficient than a straightforward Monte Carlo analysis, with demonstrated speedup factors up to 2500.

Chronic diseases are not being managed effectively in either high-risk or low-risk populations in South Africa.

PubMed

Brand, Martin; Woodiwiss, Angela J; Michel, Frederic; Booysens, Hendrik L; Majane, Olebogeng H I; Maseko, Muzi J; Veller, Martin G; Norton, Gavin R

2013-07-29

Primary healthcare is the foundation of a country's healthcare system. Without an efficient and cost-effective programme, the level of healthcare offered across all levels of health management is adversely affected. To analyse the effectiveness of the management of hypertension and diabetes mellitus (DM) among two distinct patient populations, one with significant cardiovascular risk factors and the other without. We performed a case control study of a high-risk group of patients presenting with chronic critical limb ischaemia (CLI) to the Divisions of Vascular Surgery at Charlotte Maxeke Johannesburg Academic Hospital and Chris Hani Baragwanath Academic Hospital, and a randomly selected group of 'healthy' community participants from Johannesburg's South Western Townships (Soweto). We assessed 217 patients with CLI and 1 030 participants from the community. We assessed the number of patients who were not achieving their therapeuatic targets, among those known to be hypertensive (CLI: 44.7%; community: 59.9%) and diabetic (CLI: 83.5%; community: 66%). Undiagnosed diabetes affected 10.8% of patients with CLI and 11% of the community sample. Traditional vascular risk factors are managed poorly at both primary healthcare and at tertiary care levels. There is a need to identify factors that will address this issue.

[Identification of ecological corridors and its importance by integrating circuit theory].

PubMed

Song, Li Li; Qin, Ming Zhou

2016-10-01

Landscape connectivity is considered as an extraordinarily important factor affecting various ecological processes. The least cost path (LCP) on the basis of minimum cumulative resis-tance model (MCRM) may provide a more efficient approach to identify functional connectivity in heterogeneous landscapes, and is already adopted by the research of landscape functional connecti-vity assessment and ecological corridor simulation. Connectivity model on circuit theory (CMCT) replaced the edges in the graph theory with resistors, cost distance with resistance distance to measure the functional connectivity in heterogeneous landscapes. By means of Linkage Mapper tool and Circuitscape software, the simulated landscape generated from SIMMAP 2.0 software was viewed as the study object in this article, aimed at exploring how to integrate MCRM with CMCT to identify ecological corridors and relative importance of landscape factors. The results showed that two models had their individual advantages and mutual complement. MCRM could effectively identify least cost corridors among habitats. CMCT could effectively identify important landscape factor and pinch point, which had important influence on landscape connectivity. We also found that the position of pinch point was not affected by corridor width, which had obvious advantage in the research of identifying the importance of corridors. The integrated method could provide certain scientific basis for regional ecological protection planning and ecological corridor design.

Dynamic factor analysis for estimating ground water arsenic trends.

PubMed

Kuo, Yi-Ming; Chang, Fi-John

2010-01-01

Drinking ground water containing high arsenic (As) concentrations has been associated with blackfoot disease and the occurrence of cancer along the southwestern coast of Taiwan. As a result, 28 ground water observation wells were installed to monitor the ground water quality in this area. Dynamic factor analysis (DFA) is used to identify common trends that represent unexplained variability in ground water As concentrations of decommissioned wells and to investigate whether explanatory variables (total organic carbon [TOC], As, alkalinity, ground water elevation, and rainfall) affect the temporal variation in ground water As concentration. The results of the DFA show that rainfall dilutes As concentration in areas under aquacultural and agricultural use. Different combinations of geochemical variables (As, alkalinity, and TOC) of nearby monitoring wells affected the As concentrations of the most decommissioned wells. Model performance was acceptable for 11 wells (coefficient of efficiency >0.50), which represents 52% (11/21) of the decommissioned wells. Based on DFA results, we infer that surface water recharge may be effective for diluting the As concentration, especially in the areas that are relatively far from the coastline. We demonstrate that DFA can effectively identify the important factors and common effects representing unexplained variability common to decommissioned wells on As variation in ground water and extrapolate information from existing monitoring wells to the nearby decommissioned wells.

The dynamic monitoring of aeolian desertification land distribution and its response to climate change in northern China

NASA Astrophysics Data System (ADS)

Feng, Lili; Jia, Zhiqing; Li, Qingxue

2016-12-01

Aeolian desertification is poorly understood despite its importance for indicating environment change. Here we exploit Gaofen-1(GF-1) and Moderate Resolution Imaging Spectroradiometer (MODIS) data to develop a quick and efficient method for large scale aeolian desertification dynamic monitoring in northern China. This method, which is based on Normalized Difference Desertification Index (NDDI) calculated by band1 & band2 of MODIS reflectance data (MODIS09A1). Then we analyze spatial-temporal change of aeolian desertification area and detect its possible influencing factors, such as precipitation, temperature, wind speed and population by Convergent Cross Mapping (CCM) model. It suggests that aeolian desertification area with population indicates feedback (bi-directional causality) between the two variables (P < 0.05), but forcing of aeolian desertification area by population is weak. Meanwhile, we find aeolian desertification area is significantly affected by temperature, as expected. However, there is no obvious forcing for the aeolian desertification area and precipitation. Aeolian desertification area with wind speed indicates feedback (bi-directional causality) between the two variables with significant signal (P < 0.01). We infer that aeolian desertification is greatly affected by natural factors compared with anthropogenic factors. For the desertification in China, we are greatly convinced that desertification prevention is better than control.

The dynamic monitoring of aeolian desertification land distribution and its response to climate change in northern China

PubMed Central

Feng, Lili; Jia, Zhiqing; Li, Qingxue

2016-01-01

Aeolian desertification is poorly understood despite its importance for indicating environment change. Here we exploit Gaofen-1(GF-1) and Moderate Resolution Imaging Spectroradiometer (MODIS) data to develop a quick and efficient method for large scale aeolian desertification dynamic monitoring in northern China. This method, which is based on Normalized Difference Desertification Index (NDDI) calculated by band1 & band2 of MODIS reflectance data (MODIS09A1). Then we analyze spatial-temporal change of aeolian desertification area and detect its possible influencing factors, such as precipitation, temperature, wind speed and population by Convergent Cross Mapping (CCM) model. It suggests that aeolian desertification area with population indicates feedback (bi-directional causality) between the two variables (P < 0.05), but forcing of aeolian desertification area by population is weak. Meanwhile, we find aeolian desertification area is significantly affected by temperature, as expected. However, there is no obvious forcing for the aeolian desertification area and precipitation. Aeolian desertification area with wind speed indicates feedback (bi-directional causality) between the two variables with significant signal (P < 0.01). We infer that aeolian desertification is greatly affected by natural factors compared with anthropogenic factors. For the desertification in China, we are greatly convinced that desertification prevention is better than control. PMID:28004798

The effects of alphabet and expertise on letter perception

PubMed Central

Wiley, Robert W.; Wilson, Colin; Rapp, Brenda

2016-01-01

Long-standing questions in human perception concern the nature of the visual features that underlie letter recognition and the extent to which the visual processing of letters is affected by differences in alphabets and levels of viewer expertise. We examined these issues in a novel approach using a same-different judgment task on pairs of letters from the Arabic alphabet with two participant groups—one with no prior exposure to Arabic and one with reading proficiency. Hierarchical clustering and linear mixed-effects modeling of reaction times and accuracy provide evidence that both the specific characteristics of the alphabet and observers’ previous experience with it affect how letters are perceived and visually processed. The findings of this research further our understanding of the multiple factors that affect letter perception and support the view of a visual system that dynamically adjusts its weighting of visual features as expert readers come to more efficiently and effectively discriminate the letters of the specific alphabet they are viewing. PMID:26913778

Translation efficiency is determined by both codon bias and folding energy

PubMed Central

Tuller, Tamir; Waldman, Yedael Y.; Kupiec, Martin; Ruppin, Eytan

2010-01-01

Synonymous mutations do not alter the protein produced yet can have a significant effect on protein levels. The mechanisms by which this effect is achieved are controversial; although some previous studies have suggested that codon bias is the most important determinant of translation efficiency, a recent study suggested that mRNA folding at the beginning of genes is the dominant factor via its effect on translation initiation. Using the Escherichia coli and Saccharomyces cerevisiae transcriptomes, we conducted a genome-scale study aiming at dissecting the determinants of translation efficiency. There is a significant association between codon bias and translation efficiency across all endogenous genes in E. coli and S. cerevisiae but no association between folding energy and translation efficiency, demonstrating the role of codon bias as an important determinant of translation efficiency. However, folding energy does modulate the strength of association between codon bias and translation efficiency, which is maximized at very weak mRNA folding (i.e., high folding energy) levels. We find a strong correlation between the genomic profiles of ribosomal density and genomic profiles of folding energy across mRNA, suggesting that lower folding energies slow down the ribosomes and decrease translation efficiency. Accordingly, we find that selection forces act near uniformly to decrease the folding energy at the beginning of genes. In summary, these findings testify that in endogenous genes, folding energy affects translation efficiency in a global manner that is not related to the expression levels of individual genes, and thus cannot be detected by correlation with their expression levels. PMID:20133581

A Sector Capacity Assessment Method Based on Airspace Utilization Efficiency

NASA Astrophysics Data System (ADS)

Zhang, Jianping; Zhang, Ping; Li, Zhen; Zou, Xiang

2018-02-01

Sector capacity is one of the core factors affecting the safety and the efficiency of the air traffic system. Most of previous sector capacity assessment methods only considered the air traffic controller’s (ATCO’s) workload. These methods are not only limited which only concern about the safety, but also not accurate enough. In this paper, we employ the integrated quantitative index system proposed in one of our previous literatures. We use the principal component analysis (PCA) to find out the principal indicators among the indicators so as to calculate the airspace utilization efficiency. In addition, we use a series of fitting functions to test and define the correlation between the dense of air traffic flow and the airspace utilization efficiency. The sector capacity is then decided as the value of the dense of air traffic flow corresponding to the maximum airspace utilization efficiency. We also use the same series of fitting functions to test the correlation between the dese of air traffic flow and the ATCOs’ workload. We examine our method with a large amount of empirical operating data of Chengdu Controlling Center and obtain a reliable sector capacity value. Experiment results also show superiority of our method against those only consider the ATCO’s workload in terms of better correlation between the airspace utilization efficiency and the dense of air traffic flow.

The Effect of Compression Ratio, Fuel Octane Rating, and Ethanol Content on Spark-Ignition Engine Efficiency.

PubMed

Leone, Thomas G; Anderson, James E; Davis, Richard S; Iqbal, Asim; Reese, Ronald A; Shelby, Michael H; Studzinski, William M

2015-09-15

Light-duty vehicles (LDVs) in the United States and elsewhere are required to meet increasingly challenging regulations on fuel economy and greenhouse gas (GHG) emissions as well as criteria pollutant emissions. New vehicle trends to improve efficiency include higher compression ratio, downsizing, turbocharging, downspeeding, and hybridization, each involving greater operation of spark-ignited (SI) engines under higher-load, knock-limited conditions. Higher octane ratings for regular-grade gasoline (with greater knock resistance) are an enabler for these technologies. This literature review discusses both fuel and engine factors affecting knock resistance and their contribution to higher engine efficiency and lower tailpipe CO2 emissions. Increasing compression ratios for future SI engines would be the primary response to a significant increase in fuel octane ratings. Existing LDVs would see more advanced spark timing and more efficient combustion phasing. Higher ethanol content is one available option for increasing the octane ratings of gasoline and would provide additional engine efficiency benefits for part and full load operation. An empirical calculation method is provided that allows estimation of expected vehicle efficiency, volumetric fuel economy, and CO2 emission benefits for future LDVs through higher compression ratios for different assumptions on fuel properties and engine types. Accurate "tank-to-wheel" estimates of this type are necessary for "well-to-wheel" analyses of increased gasoline octane ratings in the context of light duty vehicle transportation.

High and Dry? Stomatal Regulation and the Water Use Efficiency of Vegetation

NASA Astrophysics Data System (ADS)

Seibt, U.; Maseyk, K. S.; Sun, W.; Lett, C.; Pivovaroff, A. L.

2016-12-01

The water use efficiency (WUE, ratio of carbon assimilated to water transpired) of vegetation plays an important role in determining the exchange of water between ecosystems and the atmosphere and thus affects the global water cycle. It also shapes the water-energy balance of ecosystems as a decrease in water fluxes may lead to an increase in surface temperature. A large number of studies have reported systematic changes in WUE from the stand to landscape scale, however, there is no general agreement on the sign and magnitude of the observed trends. The divergent responses reflect that the WUE of vegetation is shaped by a complex interplay of factors acting on a wide range of temporal scales: On diurnal to seasonal time scales, if evaporative demand is altered by atmospheric moisture or temperature, plants respond by adjusting stomatal conductance with associated changes in both transpiration and photosynthetic carbon uptake. On seasonal to interannual time scales, leaf size, structure and activity may adapt to water stress. This can alter boundary layer and mesophyll conductances, radiation profiles, and the surface energy balance. On longer time scales, the carbon-water balance of ecosystems is additionally affected by the ongoing global rise in CO2 and temperatures. Stomatal regulation is a central factor across all scales. We present new results on leaf and stand scale WUE from a range of ecosystems (arctic, boreal, semi-arid, tropical), and discuss the role of stomatal regulation on diurnal and seasonal changes in WUE in response to water stress and on potential long-term trends in WUE in response to climate change.

Data decomposition method for parallel polygon rasterization considering load balancing

NASA Astrophysics Data System (ADS)

Zhou, Chen; Chen, Zhenjie; Liu, Yongxue; Li, Feixue; Cheng, Liang; Zhu, A.-xing; Li, Manchun

2015-12-01

It is essential to adopt parallel computing technology to rapidly rasterize massive polygon data. In parallel rasterization, it is difficult to design an effective data decomposition method. Conventional methods ignore load balancing of polygon complexity in parallel rasterization and thus fail to achieve high parallel efficiency. In this paper, a novel data decomposition method based on polygon complexity (DMPC) is proposed. First, four factors that possibly affect the rasterization efficiency were investigated. Then, a metric represented by the boundary number and raster pixel number in the minimum bounding rectangle was developed to calculate the complexity of each polygon. Using this metric, polygons were rationally allocated according to the polygon complexity, and each process could achieve balanced loads of polygon complexity. To validate the efficiency of DMPC, it was used to parallelize different polygon rasterization algorithms and tested on different datasets. Experimental results showed that DMPC could effectively parallelize polygon rasterization algorithms. Furthermore, the implemented parallel algorithms with DMPC could achieve good speedup ratios of at least 15.69 and generally outperformed conventional decomposition methods in terms of parallel efficiency and load balancing. In addition, the results showed that DMPC exhibited consistently better performance for different spatial distributions of polygons.

Improving laboratory efficiencies to scale-up HIV viral load testing.

PubMed

Alemnji, George; Onyebujoh, Philip; Nkengasong, John N

2017-03-01

Viral load measurement is a key indicator that determines patients' response to treatment and risk for disease progression. Efforts are ongoing in different countries to scale-up access to viral load testing to meet the Joint United Nations Programme on HIV and AIDS target of achieving 90% viral suppression among HIV-infected patients receiving antiretroviral therapy. However, the impact of these initiatives may be challenged by increased inefficiencies along the viral load testing spectrum. This will translate to increased costs and ineffectiveness of scale-up approaches. This review describes different parameters that could be addressed across the viral load testing spectrum aimed at improving efficiencies and utilizing test results for patient management. Though progress is being made in some countries to scale-up viral load, many others still face numerous challenges that may affect scale-up efficiencies: weak demand creation, ineffective supply chain management systems; poor specimen referral systems; inadequate data and quality management systems; and weak laboratory-clinical interface leading to diminished uptake of test results. In scaling up access to viral load testing, there should be a renewed focus to address efficiencies across the entire spectrum, including factors related to access, uptake, and impact of test results.

Interpersonal relationships and safety culture in Brazilian health care organisations.

PubMed

Migowski, Eliana R; Oliveira Júnior, Nery; Riegel, Fernando; Migowski, Sérgio A

2018-06-20

To examine the association between interpersonal relationships, nursing leadership and patient safety culture and the impact on the efficiency of hospitals. Hospitals are still affected by the increased complexity of the treatments offered and by the diverse knowledge of professionals involved, which has made this assistance model ineffective, expensive and unsustainable over time. A qualitative study of 32 professionals from three large hospitals in Southern Brazil was made. Semi-structured interviews, document analysis and analysis of electronic records were used. All the hospitals had infection rates and an average stay higher than their goal. Lack of interpersonal relationships and physicians failing to commit to organisational objectives were demonstrated. Nursing leadership styles are not definitive factors to improving patient safety and efficiency. The flaws in consolidating interpersonal relationships seem to be related to difficulties in consolidating patient safety culture, which prevented hospitals reaching their efficiency indicators. Professionals who work at the patients' bedside should be involved in the development of strategies, in order to commit them to the organisational objectives. The consolidation of interpersonal relationships of nursing professionals can lead to improvements with medical professionals, with positive impacts on patient safety and efficiency. © 2018 John Wiley & Sons Ltd.