Globalization and Economic Freedom

DEFF Research Database (Denmark)

Bjørnskov, Christian

2006-01-01

This paper employs a panel data set to estimate the effect of globalization on four measures of economic freedom. Contrary to previous studies, the paper distinguishes between three separate types of globalization: economic, social and political. It also separates effects for poor and rich...... countries, and autocracies and democracies. The results show that economic globalization is negatively associated with government size and positively with regulatory freedom in rich countries; social globalization is positively associated with legal quality in autocracies and with the access to sound money...... in democracies. Political globalization is not associated with economic freedom...

Nonstandard scaling law of fluctuations in finite-size systems of globally coupled oscillators.

Science.gov (United States)

Nishikawa, Isao; Tanaka, Gouhei; Aihara, Kazuyuki

2013-08-01

Universal scaling laws form one of the central issues in physics. A nonstandard scaling law or a breakdown of a standard scaling law, on the other hand, can often lead to the finding of a new universality class in physical systems. Recently, we found that a statistical quantity related to fluctuations follows a nonstandard scaling law with respect to the system size in a synchronized state of globally coupled nonidentical phase oscillators [I. Nishikawa et al., Chaos 22, 013133 (2012)]. However, it is still unclear how widely this nonstandard scaling law is observed. In the present paper, we discuss the conditions required for the unusual scaling law in globally coupled oscillator systems and validate the conditions by numerical simulations of several different models.

Size-resolved chemical composition, effective density, and optical properties of biomass burning particles

Science.gov (United States)

Zhai, Jinghao; Lu, Xiaohui; Li, Ling; Zhang, Qi; Zhang, Ci; Chen, Hong; Yang, Xin; Chen, Jianmin

2017-06-01

Biomass burning aerosol has an important impact on the global radiative budget. A better understanding of the correlations between the mixing states of biomass burning particles and their optical properties is the goal of a number of current studies. In this work, the effective density, chemical composition, and optical properties of rice straw burning particles in the size range of 50-400 nm were measured using a suite of online methods. We found that the major components of particles produced by burning rice straw included black carbon (BC), organic carbon (OC), and potassium salts, but the mixing states of particles were strongly size dependent. Particles of 50 nm had the smallest effective density (1.16 g cm-3) due to a relatively large proportion of aggregate BC. The average effective densities of 100-400 nm particles ranged from 1.35 to 1.51 g cm-3 with OC and inorganic salts as dominant components. Both density distribution and single-particle mass spectrometry showed more complex mixing states in larger particles. Upon heating, the separation of the effective density distribution modes confirmed the external mixing state of less-volatile BC or soot and potassium salts. The size-resolved optical properties of biomass burning particles were investigated at two wavelengths (λ = 450 and 530 nm). The single-scattering albedo (SSA) showed the lowest value for 50 nm particles (0.741 ± 0.007 and 0.889 ± 0.006) because of the larger proportion of BC content. Brown carbon played an important role for the SSA of 100-400 nm particles. The Ångström absorption exponent (AAE) values for all particles were above 1.6, indicating the significant presence of brown carbon in all sizes. Concurrent measurements in our work provide a basis for discussing the physicochemical properties of biomass burning aerosol and its effects on the global climate and atmospheric environment.

Effect Sizes in Gifted Education Research

Science.gov (United States)

Gentry, Marcia; Peters, Scott J.

2009-01-01

Recent calls for reporting and interpreting effect sizes have been numerous, with the 5th edition of the "Publication Manual of the American Psychological Association" (2001) calling for the inclusion of effect sizes to interpret quantitative findings. Many top journals have required that effect sizes accompany claims of statistical significance.…

The Effect of Visual Feedback on Writing Size in Parkinson’s Disease

Directory of Open Access Journals (Sweden)

Adriaan R. E. Potgieser

2015-01-01

Full Text Available Parkinson’s disease (PD leads to impairment in multiple cognitive domains. Micrographia is a relatively early PD sign of visuomotor dysfunction, characterized by a global reduction in writing size and a decrement in size during writing. Here we aimed to investigate the effect of withdrawal of visual feedback on writing size in patients with PD. Twenty-five patients with non-tremor-dominant PD without cognitive dysfunction and twenty-five age-matched controls had to write a standard sentence with and without visual feedback. We assessed the effect of withdrawal of visual feedback by measuring vertical word size (i, horizontal length of the sentence (ii, and the summed horizontal word length without interspacing (iii, comparing patients with controls. In both patients and controls, writing was significantly larger without visual feedback. This enlargement did not significantly differ between the groups. Smaller handwriting significantly correlated with increased disease severity. Contrary to previous observations that withdrawal of visual feedback caused increased writing size in specifically PD, we did not find differences between patients and controls. Both groups wrote larger without visual feedback, which adds insight in general neuronal mechanisms underlying the balance between feed-forward and feedback in visuomotor control, mechanisms that also hold for grasping movements.

[Effect sizes, statistical power and sample sizes in "the Japanese Journal of Psychology"].

Science.gov (United States)

Suzukawa, Yumi; Toyoda, Hideki

2012-04-01

This study analyzed the statistical power of research studies published in the "Japanese Journal of Psychology" in 2008 and 2009. Sample effect sizes and sample statistical powers were calculated for each statistical test and analyzed with respect to the analytical methods and the fields of the studies. The results show that in the fields like perception, cognition or learning, the effect sizes were relatively large, although the sample sizes were small. At the same time, because of the small sample sizes, some meaningful effects could not be detected. In the other fields, because of the large sample sizes, meaningless effects could be detected. This implies that researchers who could not get large enough effect sizes would use larger samples to obtain significant results.

Size effects in shear interfaces

OpenAIRE

GARNIER, J

2001-01-01

In physical modelling (centrifuge tests, calibration chambers, laboratory tests), the size of the soil particles may not be negligible when compared to the dimensions of the models. Size effects may so disturb the response of the models and the experimental data obtained on these cannot be extended to true scale conditions. Different tests have been performed to study and quantify the size effects that may happen in shear interfaces between soils and structures : modified shear box tests, pul...

A Primer on Basic Effect Size Concepts.

Science.gov (United States)

Elmore, Patricia B.; Rotou, Ourania

The increased interest in reporting effect sizes means that it is necessary to consider what should be included in a primer on effect sizes. A review of papers on effect sizes and commonly repeated statistical analyses suggests that it is important to discuss effect sizes relative to bivariate correlation, t-tests, analysis of variance/covariance,…

How the Emitted Size Distribution and Mixing State of Feldspar Affect Ice Nucleating Particles in a Global Model

Science.gov (United States)

Perlwitz, J. P.; Fridlind, A. M.; Knopf, D. A.; Miller, R. L.; Pérez García-Pando, C.

2017-12-01

The effect of aerosol particles on ice nucleation and, in turn, the formation of ice and mixed phase clouds is recognized as one of the largest sources of uncertainty in climate prediction. We apply an improved dust mineral specific aerosol module in the NASA GISS Earth System ModelE, which takes into account soil aggregates and their fragmentation at emission as well as the emission of large particles. We calculate ice nucleating particle concentrations from K-feldspar abundance for an active site parameterization for a range of activation temperatures and external and internal mixing assumption. We find that the globally averaged INP concentration is reduced by a factor of two to three, compared to a simple assumption on the size distribution of emitted dust minerals. The decrease can amount to a factor of five in some geographical regions. The results vary little between external and internal mixing and different activation temperatures, except for the coldest temperatures. In the sectional size distribution, the size range 2-4 μm contributes the largest INP number.

How the Emitted Size Distribution and Mixing State of Feldspar Affect Ice Nucleating Particles in a Global Model

Science.gov (United States)

Perlwitz, Jan P.; Fridlind, Ann M.; Knopf, Daniel A.; Miller, Ron L.; García-Pando, Carlos Perez

2017-01-01

The effect of aerosol particles on ice nucleation and, in turn, the formation of ice and mixed phase clouds is recognized as one of the largest sources of uncertainty in climate prediction. We apply an improved dust mineral specific aerosol module in the NASA GISS Earth System ModelE, which takes into account soil aggregates and their fragmentation at emission as well as the emission of large particles. We calculate ice nucleating particle concentrations from K-feldspar abundance for an active site parameterization for a range of activation temperatures and external and internal mixing assumption. We find that the globally averaged INP concentration is reduced by a factor of two to three, compared to a simple assumption on the size distribution of emitted dust minerals. The decrease can amount to a factor of five in some geographical regions. The results vary little between external and internal mixing and different activation temperatures, except for the coldest temperatures. In the sectional size distribution, the size range 24 micrometer contributes the largest INP number.

Size effects in manufacturing of metallic components

DEFF Research Database (Denmark)

Vollertsen, F; Biermann, D; Hansen, Hans Nørgaard

2009-01-01

In manufacturing of metallic components, the size of the part plays an important role for the process behaviour. This is due to so called size effects, which lead to changes in the process behaviour even if the relationship between the main geometrical features is kept constant. The aim...... of this paper is to give a systematic review on Such effects and their potential use or remedy. First, the typology of size effects will be explained, followed by a description of size effects on strength and tribology. The last three sections describe size effects on formability, forming processes and cutting...... processes. (C) 2009 CIRP....

Modelling the effect of size-asymmetric competition on size inequality

DEFF Research Database (Denmark)

Rasmussen, Camilla Ruø; Weiner, Jacob

2017-01-01

Abstract The concept of size asymmetry in resource competition among plants, in which larger individuals obtain a disproportionate share of contested resources, appears to be very straightforward, but the effects of size asymmetry on growth and size variation among individuals have proved...... to be controversial. It has often been assumed that competition among individual plants in a population has to be size-asymmetric to result in higher size inequality than in the absence of competition, but here we question this inference. Using very simple, individual-based models, we investigate how size symmetry...... of competition affects the development in size inequality between two competing plants and show that increased size inequality due to competition is not always strong evidence for size-asymmetric competition. Even absolute symmetric competition, in which all plants receive the same amount of resources...

Macroscale patterns in body size of intertidal crustaceans provide insights on climate change effects

Science.gov (United States)

Dugan, Jenifer E.; Hubbard, David M.; Contreras, Heraldo; Duarte, Cristian; Acuña, Emilio; Schoeman, David S.

2017-01-01

Predicting responses of coastal ecosystems to altered sea surface temperatures (SST) associated with global climate change, requires knowledge of demographic responses of individual species. Body size is an excellent metric because it scales strongly with growth and fecundity for many ectotherms. These attributes can underpin demographic as well as community and ecosystem level processes, providing valuable insights for responses of vulnerable coastal ecosystems to changing climate. We investigated contemporary macroscale patterns in body size among widely distributed crustaceans that comprise the majority of intertidal abundance and biomass of sandy beach ecosystems of the eastern Pacific coasts of Chile and California, USA. We focused on ecologically important species representing different tidal zones, trophic guilds and developmental modes, including a high-shore macroalga-consuming talitrid amphipod (Orchestoidea tuberculata), two mid-shore scavenging cirolanid isopods (Excirolana braziliensis and E. hirsuticauda), and a low-shore suspension-feeding hippid crab (Emerita analoga) with an amphitropical distribution. Significant latitudinal patterns in body sizes were observed for all species in Chile (21° - 42°S), with similar but steeper patterns in Emerita analoga, in California (32°- 41°N). Sea surface temperature was a strong predictor of body size (-4% to -35% °C-1) in all species. Beach characteristics were subsidiary predictors of body size. Alterations in ocean temperatures of even a few degrees associated with global climate change are likely to affect body sizes of important intertidal ectotherms, with consequences for population demography, life history, community structure, trophic interactions, food-webs, and indirect effects such as ecosystem function. The consistency of results for body size and temperature across species with different life histories, feeding modes, ecological roles, and microhabitats inhabiting a single widespread coastal

Finite-size effects on current correlation functions

Science.gov (United States)

Chen, Shunda; Zhang, Yong; Wang, Jiao; Zhao, Hong

2014-02-01

We study why the calculation of current correlation functions (CCFs) still suffers from finite-size effects even when the periodic boundary condition is taken. Two important one-dimensional, momentum-conserving systems are investigated as examples. Intriguingly, it is found that the state of a system recurs in the sense of microcanonical ensemble average, and such recurrence may result in oscillations in CCFs. Meanwhile, we find that the sound mode collisions induce an extra time decay in a current so that its correlation function decays faster (slower) in a smaller (larger) system. Based on these two unveiled mechanisms, a procedure for correctly evaluating the decay rate of a CCF is proposed, with which our analysis suggests that the global energy CCF decays as ˜t-2/3 in the diatomic hard-core gas model and in a manner close to ˜t-1/2 in the Fermi-Pasta-Ulam-β model.

Effect size estimates: current use, calculations, and interpretation.

Science.gov (United States)

Fritz, Catherine O; Morris, Peter E; Richler, Jennifer J

2012-02-01

The Publication Manual of the American Psychological Association (American Psychological Association, 2001, American Psychological Association, 2010) calls for the reporting of effect sizes and their confidence intervals. Estimates of effect size are useful for determining the practical or theoretical importance of an effect, the relative contributions of factors, and the power of an analysis. We surveyed articles published in 2009 and 2010 in the Journal of Experimental Psychology: General, noting the statistical analyses reported and the associated reporting of effect size estimates. Effect sizes were reported for fewer than half of the analyses; no article reported a confidence interval for an effect size. The most often reported analysis was analysis of variance, and almost half of these reports were not accompanied by effect sizes. Partial η2 was the most commonly reported effect size estimate for analysis of variance. For t tests, 2/3 of the articles did not report an associated effect size estimate; Cohen's d was the most often reported. We provide a straightforward guide to understanding, selecting, calculating, and interpreting effect sizes for many types of data and to methods for calculating effect size confidence intervals and power analysis.

Letters in the Forest: Global precedence effect disappears for letters but not for non-letters under reading-like conditions

Directory of Open Access Journals (Sweden)

Thomas eLachmann

2014-07-01

Full Text Available Normally-skilled reading involves special processing strategies for letters, which are habitually funneled into an abstract letter code. On the basis of previous studies we argue that this habit leads to the preferred usage of an analytic strategy for the processing of letters, while non-letters are preferably processed via a holistic strategy. The well-known Global Precedence Effect (GPE seems to contradict to this assumption, since, with compound, hierarchical figures, including letter items, faster responses are observed to the global than to the local level of the figure, as well as an asymmetric interference effect from global to local level. We argue that with letters these effects depend on presentation conditions; only when they elicit the processing strategies automatized for reading, an analytic strategy for letters in contrast to non-letters is to be expected. We compared the GPE for letters and non-letters in central viewing, with the global stimulus size close to the functional visual field in whole word reading (6.5o of visual angle and local stimuli close to the critical size for fluent reading of individual letters (.5o of visual angle. Under these conditions, the GPE remained robust for non-letters. For letters, however, it disappeared: letters showed no overall response time advantage for the global level and symmetric congruence effects (local-to-global as well as global-to local interference. We interpret these results as according to the view that reading is based on resident analytic visual processing strategies for letters.

Do class size effects differ across grades?

DEFF Research Database (Denmark)

Nandrup, Anne Brink

size cap that creates exogenous variation in class sizes. Significant (albeit modest) negative effects of class size increases are found for children on primary school levels. The effects on math abilities are statistically different across primary and secondary school. Larger classes do not affect......This paper contributes to the class size literature by analyzing whether short-run class size effects are constant across grade levels in compulsory school. Results are based on administrative data on all pupils enroled in Danish public schools. Identification is based on a government-imposed class...

Size Effects on the Strength of Metals

DEFF Research Database (Denmark)

Huang, Xiaoxu

2014-01-01

The grain size effect and the specimen size effect on the strength of metals are briefly reviewed with respect to their history and current status of research. It is revealed that the fundamental strengthening mechanisms responsible for these two types of size effect are to increase the resistanc...

The Effectiveness of learning materials based on multiple intelligence on the understanding of global warming

Science.gov (United States)

Liliawati, W.; Purwanto; Zulfikar, A.; Kamal, R. N.

2018-05-01

This study aims to examine the effectiveness of the use of teaching materials based on multiple intelligences on the understanding of high school students’ material on the theme of global warming. The research method used is static-group pretest-posttest design. Participants of the study were 60 high school students of XI class in one of the high schools in Bandung. Participants were divided into two classes of 30 students each for the experimental class and control class. The experimental class uses compound-based teaching materials while the experimental class does not use a compound intelligence-based teaching material. The instrument used is a test of understanding of the concept of global warming with multiple choices form amounted to 15 questions and 5 essay items. The test is given before and after it is applied to both classes. Data analysis using N-gain and effect size. The results obtained that the N-gain for both classes is in the medium category and the effectiveness of the use of teaching materials based on the results of effect-size test results obtained in the high category.

Publication Bias in Psychology: A Diagnosis Based on the Correlation between Effect Size and Sample Size

Science.gov (United States)

Kühberger, Anton; Fritz, Astrid; Scherndl, Thomas

2014-01-01

Background The p value obtained from a significance test provides no information about the magnitude or importance of the underlying phenomenon. Therefore, additional reporting of effect size is often recommended. Effect sizes are theoretically independent from sample size. Yet this may not hold true empirically: non-independence could indicate publication bias. Methods We investigate whether effect size is independent from sample size in psychological research. We randomly sampled 1,000 psychological articles from all areas of psychological research. We extracted p values, effect sizes, and sample sizes of all empirical papers, and calculated the correlation between effect size and sample size, and investigated the distribution of p values. Results We found a negative correlation of r = −.45 [95% CI: −.53; −.35] between effect size and sample size. In addition, we found an inordinately high number of p values just passing the boundary of significance. Additional data showed that neither implicit nor explicit power analysis could account for this pattern of findings. Conclusion The negative correlation between effect size and samples size, and the biased distribution of p values indicate pervasive publication bias in the entire field of psychology. PMID:25192357

Modelling of Size Effect with Regularised Continua

Directory of Open Access Journals (Sweden)

H. Askes

2004-01-01

Full Text Available A nonlocal damage continuum and a viscoplastic damage continuum are used to model size effects. Three-point bending specimens are analysed, whereby a distinction is made between unnotched specimens, specimens with a constant notch and specimens with a proportionally scaled notch. Numerical finite element simulations have been performed for specimen sizes in a range of 1:64. Size effects are established in terms of nominal strength and compared to existing size effect models from the literature. 

Finite-size effects in thermodynamics: Negative compressibility and global instability in two-phase systems

Science.gov (United States)

Todoshchenko, I.

2018-04-01

We have measured the equilibrium melting pressure of helium-4 as a function of the crystal size. Negative compressibility of a liquid with an inclusion of solid seed is predicted theoretically and verified experimentally with helium-4 crystal-superfluid system at 0.15 K. This two-phase system is shown to be stable if the crystal size is large enough, which is proven by the experiment. Crystal seeds that are too small spontaneously either melt completely or grow to a large enough size.

Nanocoatings size effect in nanostructured films

CERN Document Server

Aliofkhazraei, Mahmood

2014-01-01

Size effect in structures has been taken into consideration over the last years. In comparison with coatings with micrometer-ranged thickness, nanostructured coatings usually enjoy better and appropriate properties, such as strength and resistance. These coatings enjoy unique magnetic properties and are used with the aim of producing surfaces resistant against erosion, lubricant system, cutting tools, manufacturing hardened sporadic alloys, being resistant against oxidation and corrosion. This book reviews researches on fabrication and classification of nanostructured coatings with focus on size effect in nanometric scale. Size effect on electrochemical, mechanical and physical properties of nanocoatings are presented.

Gravitational effects of global strings

International Nuclear Information System (INIS)

Aryal, M.; Everett, A.E.

1986-01-01

We have obtained the gravitational field, in the weak-field approximation, of cosmic strings formed in a phase transition in which a global symmetry is broken (global strings). The effect of this field on light rays passing a global string is found, and the resulting formation of double images and production of discontinuities in the microwave background temperature compared with the corresponding results for gauge strings. There are some differences in the case of global strings, reflecting the fact that the space surrounding such strings is not purely conical. However, the differences between gauge and global strings with masses suitable to explain galaxy formation are small, and the task of distinguishing them observationally appears difficult at best

Structural effect of size on interracial friendship.

Science.gov (United States)

Cheng, Siwei; Xie, Yu

2013-04-30

Social contexts exert structural effects on individuals' social relationships, including interracial friendships. In this study, we posit that, net of group composition, total context size has a distinct effect on interracial friendship. Under the assumptions of (i) maximization of preference in choosing a friend, (ii) multidimensionality of preference, and (iii) preference for same-race friends, we conducted analyses using microsimulation that yielded three main findings. First, increased context size decreases the likelihood of forming an interracial friendship. Second, the size effect increases with the number of preference dimensions. Third, the size effect is diluted by noise, i.e., the random component affecting friendship formation. Analysis of actual friendship data among 4,745 American high school students yielded results consistent with the main conclusion that increased context size promotes racial segregation and discourages interracial friendship.

Firm Size Distribution in Fortune Global 500

Science.gov (United States)

Chen, Qinghua; Chen, Liujun; Liu, Kai

By analyzing the data of Fortune Global 500 firms from 1996 to 2008, we found that their ranks and revenues always obey the same distribution, which implies that worldwide firm structure has been stable for a long time. The fitting results show that simple Zipf distribution is not an ideal model for global firms, while SCL, FSS have better fitting goodness, and lognormal fitting is the best. And then, we proposed a simple explanation.

Environmental, biological and anthropogenic effects on grizzly bear body size: temporal and spatial considerations.

Science.gov (United States)

Nielsen, Scott E; Cattet, Marc R L; Boulanger, John; Cranston, Jerome; McDermid, Greg J; Shafer, Aaron B A; Stenhouse, Gordon B

2013-09-08

spoon effects was on par with the influence of contemporary regional habitat productivity, which showed that both temporal and spatial influences explain in part body size patterns in grizzly bears. Because smaller bears were found in colder and less-productive environments, we hypothesize that warming global temperatures may positively affect body mass of interior bears.

Towards the Development and Validation of a Global Field Size and Irrigation Map using Crowdsourcing, Mobile Apps and Google Earth Engine in support of GEOGLAM

Science.gov (United States)

Fritz, S.; Nordling, J.; See, L. M.; McCallum, I.; Perger, C.; Becker-Reshef, I.; Mucher, S.; Bydekerke, L.; Havlik, P.; Kraxner, F.; Obersteiner, M.

2014-12-01

The International Institute for Applied Systems Analysis (IIASA) has developed a global cropland extent map, which supports the monitoring and assessment activities of GEOGLAM (Group on Earth Observations Global Agricultural Monitoring Initiative). Through the European-funded SIGMA (Stimulating Innovation for Global Monitoring of Agriculture and its Impact on the Environment in support of GEOGLAM) project, IIASA is continuing to support GEOGLAM by providing cropland projections in the future and modelling environmental impacts on agriculture under various scenarios. In addition, IIASA is focusing on two specific elements within SIGMA: the development of a global field size and irrigation map; and mobile app development for in-situ data collection and validation of remotely-sensed products. Cropland field size is a very useful indicator for agricultural monitoring yet the information we have at a global scale is currently very limited. IIASA has already created a global map of field size at a 1 km resolution using crowdsourced data from Geo-Wiki as a first approximation. Using automatic classification of Landsat imagery and algorithms contained within Google Earth Engine, initial experimentation has shown that circular fields and landscape structures can easily be extracted. Not only will this contribute to improving the global map of field size, it can also be used to create a global map that contains a large proportion of the world's irrigated areas, which will be another useful contribution to GEOGLAM. The field size map will also be used to stratify and develop a global crop map in SIGMA. Mobile app development in support of in-situ data collection is another area where IIASA is currently working. An Android app has been built using the Open Data Toolkit (ODK) and extended further with spatial mapping capabilities called GeoODK. The app allows users to collect data on different crop types and delineate fields on the ground, which can be used to validate the

Size effect in the strength of concrete structures

Indian Academy of Sciences (India)

R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

The fracture mechanics size effect, as opposed to the Weibull statistical size effect, is a .... Solutions for TPB beam and a typical wedge-splitting geometry have been ..... Bazant Z P 1984 Size effect in blunt fracture: Concrete, rock, metal. J. Eng.

Prevention of the Portion Size Effect

NARCIS (Netherlands)

I. Versluis (Iris)

2016-01-01

markdownabstractAn increase in the portion size leads to an increase in energy intake, a phenomenon which is also referred to as the portion size effect. The increase in portion sizes in recent years is regarded as an important contributor to the increase in the prevalence of obesity. Hence, the aim

Comparison of Global Sizing Velocimetry and Phase Doppler Anemometry measurements of alternative jet fuel sprays

Science.gov (United States)

Sadr, Reza; Kannaiyan, Kumaran

2013-11-01

Atomization plays a crucial precursor role in liquid fuel combustion that directly affects the evaporation, mixing, and emission levels. Laser diagnostic techniques are often used to study the spray characteristics of liquid fuels. The objective of this work is to compare the spray measurements of Gas-to Liquid (GTL) jet fuels obtained using Global Sizing Velocimetry (GSV) and Phase Doppler Anemometry (PDA) techniques at global and local levels, respectively. The chemical and physical properties of GTL fuels are different from conventional jet fuels, owing to the difference in their production methodology. In this work, the experimental facility, the measurement techniques, and spray characteristics of two different GTL fuels are discussed and compared with those of Jet A-1 fuel. Results clearly demonstrate that although the global measurement gives an overall picture of the spray, fine details are obtained only through local measurements and complement in gaining more inferences into the spray characteristics. The results also show a close similarity in spray characteristics between GTL and Jet A-1 fuels. Funded by Qatar Science and Technology Park.

Trends in maar crater size and shape using the global Maar Volcano Location and Shape (MaarVLS) database

Science.gov (United States)

Graettinger, A. H.

2018-05-01

A maar crater is the top of a much larger subsurface diatreme structure produced by phreatomagmatic explosions and the size and shape of the crater reflects the growth history of that structure during an eruption. Recent experimental and geophysical research has shown that crater complexity can reflect subsurface complexity. Morphometry provides a means of characterizing a global population of maar craters in order to establish the typical size and shape of features. A global database of Quaternary maar crater planform morphometry indicates that maar craters are typically not circular and frequently have compound shapes resembling overlapping circles. Maar craters occur in volcanic fields that contain both small volume and complex volcanoes. The global perspective provided by the database shows that maars are common in many volcanic and tectonic settings producing a similar diversity of size and shape within and between volcanic fields. A few exceptional populations of maars were revealed by the database, highlighting directions of future research to improve our understanding on the geometry and spacing of subsurface explosions that produce maars. These outlying populations, such as anomalously large craters (>3000 m), chains of maars, and volcanic fields composed of mostly maar craters each represent a small portion of the database, but provide opportunities to reinvestigate fundamental questions on maar formation. Maar crater morphometry can be integrated with structural, hydrological studies to investigate lateral migration of phreatomagmatic explosion location in the subsurface. A comprehensive database of intact maar morphometry is also beneficial for the hunt for maar-diatremes on other planets.

Causality in Statistical Power: Isomorphic Properties of Measurement, Research Design, Effect Size, and Sample Size

Directory of Open Access Journals (Sweden)

R. Eric Heidel

2016-01-01

Full Text Available Statistical power is the ability to detect a significant effect, given that the effect actually exists in a population. Like most statistical concepts, statistical power tends to induce cognitive dissonance in hepatology researchers. However, planning for statistical power by an a priori sample size calculation is of paramount importance when designing a research study. There are five specific empirical components that make up an a priori sample size calculation: the scale of measurement of the outcome, the research design, the magnitude of the effect size, the variance of the effect size, and the sample size. A framework grounded in the phenomenon of isomorphism, or interdependencies amongst different constructs with similar forms, will be presented to understand the isomorphic effects of decisions made on each of the five aforementioned components of statistical power.

How to Estimate and Interpret Various Effect Sizes

Science.gov (United States)

Vacha-Haase, Tammi; Thompson, Bruce

2004-01-01

The present article presents a tutorial on how to estimate and interpret various effect sizes. The 5th edition of the Publication Manual of the American Psychological Association (2001) described the failure to report effect sizes as a "defect" (p. 5), and 23 journals have published author guidelines requiring effect size reporting. Although…

Patch size effects on plant species decline in an experimentally fragmented landscape.

Science.gov (United States)

Collins, Cathy D; Holt, Robert D; Foster, Bryan L

2009-09-01

Understanding local and global extinction is a fundamental objective of both basic and applied ecology. Island biogeography theory (IBT) and succession theory provide frameworks for understanding extinction in changing landscapes. We explore the relative contribution of fragment size vs. succession on species' declines by examining distributions of abundances for 18 plant species declining over time in an experimentally fragmented landscape in northeast Kansas, U.S.A. If patch size effects dominate, early-successional species should persist longer on large patches, but if successional processes dominate, the reverse should hold, because in our system woody plant colonization is accelerated on large patches. To compare the patterns in abundance among patch sizes, we characterize joint shifts in local abundance and occupancy with a new metric: rank occupancy-abundance profiles (ROAPs). As succession progressed, statistically significant patch size effects emerged for 11 of 18 species. More early-successional species persisted longer on large patches, despite the fact that woody encroachment (succession) progressed faster in these patches. Clonal perennial species persisted longer on large patches compared to small patches. All species that persisted longer on small patches were annuals that recruit from the seed bank each year. The degree to which species declined in occupancy vs. abundance varied dramatically among species: some species declined first in occupancy, others remained widespread or even expanded their distribution, even as they declined in local abundance. Consequently, species exhibited various types of rarity as succession progressed. Understanding the effect of fragmentation on extinction trajectories requires a species-by-species approach encompassing both occupancy and local abundance. We propose that ROAPs provide a useful tool for comparing the distribution of local abundances among landscape types, years, and species.

Size effects in ductile cellular solids. Part I : modeling

NARCIS (Netherlands)

Onck, P.R.; Andrews, E.W.; Gibson, L.J.

2001-01-01

In the mechanical testing of metallic foams, an important issue is the effect of the specimen size, relative to the cell size, on the measured properties. Here we analyze size effects for the modulus and strength of regular, hexagonal honeycombs under uniaxial and shear loadings. Size effects for

Biofuel manufacturing from woody biomass: effects of sieve size used in biomass size reduction.

Science.gov (United States)

Zhang, Meng; Song, Xiaoxu; Deines, T W; Pei, Z J; Wang, Donghai

2012-01-01

Size reduction is the first step for manufacturing biofuels from woody biomass. It is usually performed using milling machines and the particle size is controlled by the size of the sieve installed on a milling machine. There are reported studies about the effects of sieve size on energy consumption in milling of woody biomass. These studies show that energy consumption increased dramatically as sieve size became smaller. However, in these studies, the sugar yield (proportional to biofuel yield) in hydrolysis of the milled woody biomass was not measured. The lack of comprehensive studies about the effects of sieve size on energy consumption in biomass milling and sugar yield in hydrolysis process makes it difficult to decide which sieve size should be selected in order to minimize the energy consumption in size reduction and maximize the sugar yield in hydrolysis. The purpose of this paper is to fill this gap in the literature. In this paper, knife milling of poplar wood was conducted using sieves of three sizes (1, 2, and 4 mm). Results show that, as sieve size increased, energy consumption in knife milling decreased and sugar yield in hydrolysis increased in the tested range of particle sizes.

Effective population sizes of a major vector of human diseases, Aedes aegypti.

Science.gov (United States)

Saarman, Norah P; Gloria-Soria, Andrea; Anderson, Eric C; Evans, Benjamin R; Pless, Evlyn; Cosme, Luciano V; Gonzalez-Acosta, Cassandra; Kamgang, Basile; Wesson, Dawn M; Powell, Jeffrey R

2017-12-01

The effective population size ( N e ) is a fundamental parameter in population genetics that determines the relative strength of selection and random genetic drift, the effect of migration, levels of inbreeding, and linkage disequilibrium. In many cases where it has been estimated in animals, N e is on the order of 10%-20% of the census size. In this study, we use 12 microsatellite markers and 14,888 single nucleotide polymorphisms (SNPs) to empirically estimate N e in Aedes aegypti , the major vector of yellow fever, dengue, chikungunya, and Zika viruses. We used the method of temporal sampling to estimate N e on a global dataset made up of 46 samples of Ae. aegypti that included multiple time points from 17 widely distributed geographic localities. Our N e estimates for Ae. aegypti fell within a broad range (~25-3,000) and averaged between 400 and 600 across all localities and time points sampled. Adult census size (N c ) estimates for this species range between one and five thousand, so the N e / N c ratio is about the same as for most animals. These N e values are lower than estimates available for other insects and have important implications for the design of genetic control strategies to reduce the impact of this species of mosquito on human health.

The effects of seed size on hybrids formed between oilseed rape (Brassica napus and wild brown mustard (B. juncea.

Directory of Open Access Journals (Sweden)

Yong-Bo Liu

Full Text Available Seed size has significant implications in ecology, because of its effects on plant fitness. The hybrid seeds that result from crosses between crops and their wild relatives are often small, and the consequences of this have been poorly investigated. Here we report on plant performance of hybrid and its parental transgenic oilseed rape (Brassica napus and wild B. juncea, all grown from seeds sorted into three seed-size categories.Three seed-size categories were sorted by seed diameter for transgenic B. napus, wild B. juncea and their transgenic and non-transgenic hybrids. The seeds were sown in a field at various plant densities. Globally, small-seeded plants had delayed flowering, lower biomass, fewer flowers and seeds, and a lower thousand-seed weight. The seed-size effect varied among plant types but was not affected by plant density. There was no negative effect of seed size in hybrids, but it was correlated with reduced growth for both parents.Our results imply that the risk of further gene flow would probably not be mitigated by the small size of transgenic hybrid seeds. No fitness cost was detected to be associated with the Bt-transgene in this study.

Electrokinetic Flow in Microchannels with Finite Reservoir Size Effects

International Nuclear Information System (INIS)

Yan, D; Yang, C; Nguyen, N-T; Huang, X

2006-01-01

In electrokinetically-driven microfluidic applications, reservoirs are indispensable and have finite sizes. During operation processes, as the liquid level difference in reservoirs keeps changing as time elapses, the flow characteristics in a microchannel exhibit a combination of the electroosmotic flow and the time-dependent induced backpressure-driven flow. In this work, an assessment of the finite reservoir size effect on electroosmotic flows is presented theoretically and experimentally. A model is developed to describe the timedependent electrokinetic flow with finite reservoir size effects. The theoretical analysis shows that under certain conditions the finite reservoir size effect is significant. The important parameters that describe the effect of finite reservoir size on the flow characteristics are discussed. A new concept denoted as 'effective pumping period' is introduced to characterize the reservoir size effect. The proposed model clearly identifies the mechanisms of the finitereservoir size effects and is further confirmed by using micro-PIV technique. The results of this study can be used for facilitating the design of microfluidic devices

Statistical properties of four effect-size measures for mediation models.

Science.gov (United States)

Miočević, Milica; O'Rourke, Holly P; MacKinnon, David P; Brown, Hendricks C

2018-02-01

This project examined the performance of classical and Bayesian estimators of four effect size measures for the indirect effect in a single-mediator model and a two-mediator model. Compared to the proportion and ratio mediation effect sizes, standardized mediation effect-size measures were relatively unbiased and efficient in the single-mediator model and the two-mediator model. Percentile and bias-corrected bootstrap interval estimates of ab/s Y , and ab(s X )/s Y in the single-mediator model outperformed interval estimates of the proportion and ratio effect sizes in terms of power, Type I error rate, coverage, imbalance, and interval width. For the two-mediator model, standardized effect-size measures were superior to the proportion and ratio effect-size measures. Furthermore, it was found that Bayesian point and interval summaries of posterior distributions of standardized effect-size measures reduced excessive relative bias for certain parameter combinations. The standardized effect-size measures are the best effect-size measures for quantifying mediated effects.

Global cloud condensation nuclei influenced by carbonaceous combustion aerosol

Directory of Open Access Journals (Sweden)

D. V. Spracklen

2011-09-01

Full Text Available Black carbon in carbonaceous combustion aerosol warms the climate by absorbing solar radiation, meaning reductions in black carbon emissions are often perceived as an attractive global warming mitigation option. However, carbonaceous combustion aerosol can also act as cloud condensation nuclei (CCN so they also cool the climate by increasing cloud albedo. The net radiative effect of carbonaceous combustion aerosol is uncertain because their contribution to CCN has not been evaluated on the global scale. By combining extensive observations of CCN concentrations with the GLOMAP global aerosol model, we find that the model is biased low (normalised mean bias = −77 % unless carbonaceous combustion aerosol act as CCN. We show that carbonaceous combustion aerosol accounts for more than half (52–64 % of global CCN with the range due to uncertainty in the emitted size distribution of carbonaceous combustion particles. The model predicts that wildfire and pollution (fossil fuel and biofuel carbonaceous combustion aerosol causes a global mean cloud albedo aerosol indirect effect of −0.34 W m⁻², with stronger cooling if we assume smaller particle emission size. We calculate that carbonaceous combustion aerosol from pollution sources cause a global mean aerosol indirect effect of −0.23 W m⁻². The small size of carbonaceous combustion particles from fossil fuel sources means that whilst pollution sources account for only one-third of the emitted mass they cause two-thirds of the cloud albedo aerosol indirect effect that is due to carbonaceous combustion aerosol. This cooling effect must be accounted for, along with other cloud effects not studied here, to ensure that black carbon emissions controls that reduce the high number concentrations of fossil fuel particles have the desired net effect on climate.

Size effects in crystal plasticity

DEFF Research Database (Denmark)

Borg, Ulrik

2007-01-01

Numerical analyses of plasticity size effects have been carried out for different problems using a developed strain gradient crystal plasticiy theory. The theory employs higher order stresses as work conjugates to slip gradients and uses higher order boundary conditions. Problems on localization...... of plastic flow in a single crystal, grain boundary effects in a bicrystal, and grain size effects in a polycrystal are studied. Single crystals containing micro-scale voids have also been analyzed at different loading conditions with focus on the stress and deformation fields around the voids, on void...... growth and interaction between neighboring voids, and on a comparison between the developed strain gradient crystal plasticity theory and a discrete dislocation plasticity theory. Furthermore, voids and rigid inclusions in isotropic materials have been studied using a strain gradient plasticity theory...

The effect of global warming on infectious diseases.

Science.gov (United States)

Kurane, Ichiro

2010-12-01

Global warming has various effects on human health. The main indirect effects are on infectious diseases. Although the effects on infectious diseases will be detected worldwide, the degree and types of the effect are different, depending on the location of the respective countries and socioeconomical situations. Among infectious diseases, water- and foodborne infectious diseases and vector-borne infectious diseases are two main categories that are forecasted to be most affected. The effect on vector-borne infectious diseases such as malaria and dengue fever is mainly because of the expansion of the infested areas of vector mosquitoes and increase in the number and feeding activity of infected mosquitoes. There will be increase in the number of cases with water- and foodborne diarrhoeal diseases. Even with the strongest mitigation procedures, global warming cannot be avoided for decades. Therefore, implementation of adaptation measures to the effect of global warming is the most practical action we can take. It is generally accepted that the impacts of global warming on infectious diseases have not been apparent at this point yet in East Asia. However, these impacts will appear in one form or another if global warming continues to progress in future. Further research on the impacts of global warming on infectious diseases and on future prospects should be conducted.

Interpreting and Reporting Effect Sizes in Research Investigations.

Science.gov (United States)

Tapia, Martha; Marsh, George E., II

Since 1994, the American Psychological Association (APA) has advocated the inclusion of effect size indices in reporting research to elucidate the statistical significance of studies based on sample size. In 2001, the fifth edition of the APA "Publication Manual" stressed the importance of including an index of effect size to clarify…

Global Change Effects on Plant-Soil Interactions

DEFF Research Database (Denmark)

Dam, Marie

of this dissertation has been to determine how soil food web structure and function is affected when the quantity and quality of plant input is altered under global change. By studying the abundance and composition of soil organisms, particularly those in the rhizosphere, closely associated with living plants, we...... (Paper III). Furthermore, by way of meta-analysis, the role of organisms in global change effects on ecosystem function is modelled (Paper IV). Among CO2, warming and summer drought, CO2 is the factor most consistently impacting soil organisms. CO2 increases abundance of microorganisms and nematodes...... suggest that not only the global change effects on established ecosystems, but also the global change effects on plant community composition as well as land use management may determine the composition and function of soil food webs in the future....

Sample size allocation in multiregional equivalence studies.

Science.gov (United States)

Liao, Jason J Z; Yu, Ziji; Li, Yulan

2018-06-17

With the increasing globalization of drug development, the multiregional clinical trial (MRCT) has gained extensive use. The data from MRCTs could be accepted by regulatory authorities across regions and countries as the primary sources of evidence to support global marketing drug approval simultaneously. The MRCT can speed up patient enrollment and drug approval, and it makes the effective therapies available to patients all over the world simultaneously. However, there are many challenges both operationally and scientifically in conducting a drug development globally. One of many important questions to answer for the design of a multiregional study is how to partition sample size into each individual region. In this paper, two systematic approaches are proposed for the sample size allocation in a multiregional equivalence trial. A numerical evaluation and a biosimilar trial are used to illustrate the characteristics of the proposed approaches. Copyright © 2018 John Wiley & Sons, Ltd.

Global Cooling: Effect of Urban Albedo on Global Temperature

Energy Technology Data Exchange (ETDEWEB)

Akbari, Hashem; Menon, Surabi; Rosenfeld, Arthur

2007-05-22

In many urban areas, pavements and roofs constitute over 60% of urban surfaces (roof 20-25%, pavements about 40%). The roof and the pavement albedo can be increased by about 0.25 and 0.10, respectively, resulting in a net albedo increase for urban areas of about 0.1. Many studies have demonstrated building cooling-energy savings in excess of 20% upon raising roof reflectivity from an existing 10-20% to about 60%. We estimate U.S. potential savings in excess of $1 billion (B) per year in net annual energy bills. Increasing albedo of urban surfaces can reduce the summertime urban temperature and improve the urban air quality. Increasing the urban albedo has the added benefit of reflecting more of the incoming global solar radiation and countering the effect of global warming. We estimate that increasing albedo of urban areas by 0.1 results in an increase of 3 x 10{sup -4} in Earth albedo. Using a simple global model, the change in air temperature in lowest 1.8 km of the atmosphere is estimated at 0.01K. Modelers predict a warming of about 3K in the next 60 years (0.05K/year). Change of 0.1 in urban albedo will result in 0.01K global cooling, a delay of {approx}0.2 years in global warming. This 0.2 years delay in global warming is equivalent to 10 Gt reduction in CO2 emissions.

Portion size and intended consumption. Evidence for a pre-consumption portion size effect in males?

Science.gov (United States)

Robinson, Eric; te Raa, Wesselien; Hardman, Charlotte A

2015-08-01

Larger portions increase energy intake (the 'portion size effect'); however, the mechanisms behind this effect are unclear. Although pre-meal intentions are thought to be an important determinant of energy intake, little research has examined how much of a meal individuals intend to eat when served standard versus larger portion sizes. Three studies examined the effect of manipulating portion size on intended food consumption. In Studies 1 (spaghetti bolognese) and 2 (curry and rice) male participants were shown an image of either a standard or a larger meal and indicated how much of the meal they intended to consume. In Study 3 male and female participants were served either a standard or a larger portion of ice cream for dessert, they indicated how much they intended to consume and then ate as much of the ice cream as they desired. Regardless of being shown standard or large portion sizes, in Studies 1 and 2 participants reported that they intended to eat the majority of the meal, equating to a large difference in intended energy consumption between portion size conditions (a 'pre-consumption portion size effect'). This finding was replicated in male participants in Study 3, although females intended to eat a smaller proportion of the larger portion of ice cream, compared to the standard portion. Both male and female participants tended to eat in accordance with their pre-meal intentions and a portion size effect on actual consumption was subsequently observed in males, but not in females. The portion size effect may be observed when measuring pre-meal intended consumption in males. Copyright © 2015. Published by Elsevier Ltd.

The distance between Mars and Venus: measuring global sex differences in personality.

Science.gov (United States)

Del Giudice, Marco; Booth, Tom; Irwing, Paul

2012-01-01

Sex differences in personality are believed to be comparatively small. However, research in this area has suffered from significant methodological limitations. We advance a set of guidelines for overcoming those limitations: (a) measure personality with a higher resolution than that afforded by the Big Five; (b) estimate sex differences on latent factors; and (c) assess global sex differences with multivariate effect sizes. We then apply these guidelines to a large, representative adult sample, and obtain what is presently the best estimate of global sex differences in personality. Personality measures were obtained from a large US sample (N = 10,261) with the 16PF Questionnaire. Multigroup latent variable modeling was used to estimate sex differences on individual personality dimensions, which were then aggregated to yield a multivariate effect size (Mahalanobis D). We found a global effect size D = 2.71, corresponding to an overlap of only 10% between the male and female distributions. Even excluding the factor showing the largest univariate ES, the global effect size was D = 1.71 (24% overlap). These are extremely large differences by psychological standards. The idea that there are only minor differences between the personality profiles of males and females should be rejected as based on inadequate methodology.

Global indirect aerosol effects: a review

Directory of Open Access Journals (Sweden)

U. Lohmann

2005-01-01

Full Text Available Aerosols affect the climate system by changing cloud characteristics in many ways. They act as cloud condensation and ice nuclei, they may inhibit freezing and they could have an influence on the hydrological cycle. While the cloud albedo enhancement (Twomey effect of warm clouds received most attention so far and traditionally is the only indirect aerosol forcing considered in transient climate simulations, here we discuss the multitude of effects. Different approaches how the climatic implications of these aerosol effects can be estimated globally as well as improvements that are needed in global climate models in order to better represent indirect aerosol effects are discussed in this paper.

Finite size effects of a pion matrix element

International Nuclear Information System (INIS)

Guagnelli, M.; Jansen, K.; Palombi, F.; Petronzio, R.; Shindler, A.; Wetzorke, I.

2004-01-01

We investigate finite size effects of the pion matrix element of the non-singlet, twist-2 operator corresponding to the average momentum of non-singlet quark densities. Using the quenched approximation, they come out to be surprisingly large when compared to the finite size effects of the pion mass. As a consequence, simulations of corresponding nucleon matrix elements could be affected by finite size effects even stronger which could lead to serious systematic uncertainties in their evaluation

Do Class Size Effects Differ across Grades?

Science.gov (United States)

Nandrup, Anne Brink

2016-01-01

This paper contributes to the class size literature by analysing whether short-run class size effects are constant across grade levels in compulsory school. Results are based on administrative data on all pupils enrolled in Danish public schools. Identification is based on a government-imposed class size cap that creates exogenous variation in…

The globalization of training in adolescent health and medicine: one size does not fit all.

Science.gov (United States)

Leslie, Karen

2016-08-01

Adolescent medicine across the globe is practiced within a variety of healthcare models, with the shared vision of the promotion of optimal health outcomes for adolescents. In the past decade, there has been a call for transformation in how health professionals are trained, with recommendations that there be adoption of a global outlook, a multiprofessional perspective and a systems approach that considers the connections between education and health systems. Many individuals and groups are now examining how best to accomplish this educational reform. There are tensions between the call for globally accepted standards of education models and practice (a one-size fits all approach) and the need to promote the ability for education practices to be interpreted and transformed to best suit local contexts. This paper discusses some of the key considerations for 'importing' training program models for adolescent health and medicine, including the importance of cultural alignment and the utilization of best evidence and practice in health professions education.

Group size effects in two repeated game models of a global climate agreement

International Nuclear Information System (INIS)

Helland, Leif

2002-01-01

What levels of total abatement can one hope for in a global climate agreement. Some potential answers to this question are provided by game theory. This working paper contains a critical discussion of two (prominent) game ,models that answer the question quite pessimistically. Both models take the n-person, infinitely repeated prisoner's dilemma game as their point of departure. The first model is a full information model and utilises the motion of a weakly re negotiation proof equilibrium. This results in the (maybe counterintuitive) prediction that an agreement that can provide high utility to the group will attract less total abatement than an agreement that can only provide low utility to the group. The second model assumes imperfect public information and utilises the notion of a trigger level equilibrium. This results in the (more intuitive) prediction that the level of total abatements will increase with improved verification techniques for a given player set. Still the level of total abatements decrease with an increasing player set for a given verification technique. Empirical implications of the two models are identified and it is argued that one should confront these with experimentally generated data in order to discriminate between the models. One reason for this is that historical data on abatement efforts in a global climate agreement do not exist since no such agreement has entered into force yet. (Author)

Group size effects in two repeated game models of a global climate agreement

Energy Technology Data Exchange (ETDEWEB)

Helland, Leif

2002-07-01

What levels of total abatement can one hope for in a global climate agreement. Some potential answers to this question are provided by game theory. This working paper contains a critical discussion of two (prominent) game ,models that answer the question quite pessimistically. Both models take the n-person, infinitely repeated prisoner's dilemma game as their point of departure. The first model is a full information model and utilises the motion of a weakly re negotiation proof equilibrium. This results in the (maybe counterintuitive) prediction that an agreement that can provide high utility to the group will attract less total abatement than an agreement that can only provide low utility to the group. The second model assumes imperfect public information and utilises the notion of a trigger level equilibrium. This results in the (more intuitive) prediction that the level of total abatements will increase with improved verification techniques for a given player set. Still the level of total abatements decrease with an increasing player set for a given verification technique. Empirical implications of the two models are identified and it is argued that one should confront these with experimentally generated data in order to discriminate between the models. One reason for this is that historical data on abatement efforts in a global climate agreement do not exist since no such agreement has entered into force yet. (Author)

Interviewer Effects on a Network-Size Filter Question

Directory of Open Access Journals (Sweden)

Josten Michael

2016-06-01

Full Text Available There is evidence that survey interviewers may be tempted to manipulate answers to filter questions in a way that minimizes the number of follow-up questions. This becomes relevant when ego-centered network data are collected. The reported network size has a huge impact on interview duration if multiple questions on each alter are triggered. We analyze interviewer effects on a network-size question in the mixed-mode survey “Panel Study ‘Labour Market and Social Security’” (PASS, where interviewers could skip up to 15 follow-up questions by generating small networks. Applying multilevel models, we find almost no interviewer effects in CATI mode, where interviewers are paid by the hour and frequently supervised. In CAPI, however, where interviewers are paid by case and no close supervision is possible, we find strong interviewer effects on network size. As the area-specific network size is known from telephone mode, where allocation to interviewers is random, interviewer and area effects can be separated. Furthermore, a difference-in-difference analysis reveals the negative effect of introducing the follow-up questions in Wave 3 on CAPI network size. Attempting to explain interviewer effects we neither find significant main effects of experience within a wave, nor significantly different slopes between interviewers.

Size effect in tension perpendicular to the grain

DEFF Research Database (Denmark)

Pedersen, Martin Bo Uhre; Clorius, Christian Odin; Damkilde, Lars

1999-01-01

The strength in tension perpendicular to the grain is known to decrease with an increase in the stressed volume. Usually this size effect is explained on a stochastic basis, that is an explanation relying on an increased probability of encountering a strength reducing flaw when the volume...... of the material under stress is increased. This paper presents a small experimental investigation on specimens with well defined structural orientation of the material. The experiments exhibit a larger size effect than expected and furthermore the data and the nature of the failures encountered suggest...... that the size effect can be explained on a deterministic basis. Arguments for such a simple deterministic explanation of size effect is found in finite element modelling using the orthotropic stiffness characteristics in the transverse plane of wood....

The causal effect of board size in the performance of small and medium-sized firms

DEFF Research Database (Denmark)

Bennedsen, Morten; Kongsted, Hans Christian; Meisner Nielsen, Kasper

2008-01-01

correlation between family size and board size and show this correlation to be driven by firms where the CEO's relatives serve on the board. Second, we find empirical evidence of a small adverse board size effect driven by the minority of small and medium-sized firms that are characterized by having......Empirical studies of large publicly traded firms have shown a robust negative relationship between board size and firm performance. The evidence on small and medium-sized firms is less clear; we show that existing work has been incomplete in analyzing the causal relationship due to weak...... identification strategies. Using a rich data set of almost 7000 closely held corporations we provide a causal analysis of board size effects on firm performance: We use a novel instrument given by the number of children of the chief executive officer (CEO) of the firms. First, we find a strong positive...

A general equilibrium view of global rebound effects

International Nuclear Information System (INIS)

Wei Taoyuan

2010-01-01

How do energy efficiency gains affect energy consumption? The effects are generally called 'rebound effects' in the literature. Previous studies have extensively focused on only part of the global economy to study rebound effects, e.g. energy consumption by households, one industry, or one country. However, since the global economy is highly connected among countries, these studies may lead to misleading conclusions if the rebound effects in the rest of the economy are significant. Recently Saunders (2008) analyzes the demand side by taking the global economy as a whole. Wei (2007) also provides a general analysis by using Cobb-Douglas production functions for the global economy. The present article expands Wei (2007) general analysis to explore the rebound effects from an economist's viewpoint by taking the global economy as a whole and applying general forms of production functions. The analysis provides new insights related to rebound effects: we highlight the role of energy supply as a determinant of rebound. We show that the substitution between energy resources and other productive resources is more relevant to long term rebound. We predict that long term rebound may be lower than short term rebound. And we also discover that super-conservation can happen in both the short term and the long term.

Disruption effects on the beam size measurement

Energy Technology Data Exchange (ETDEWEB)

Raimondi, P.; Decker, F.J.; Chen, P.

1995-06-01

At the SLC Final Focus with higher currents and smaller beam sizes, the disruption parameter D{sub y} is close to one and so the pinch effect should produce a luminosity enhancement. Since a flat beam-beam function is fit to deflection scan data to measure the beam size, disruption can affect the measurement. Here the authors discuss the quantitative effects of disruption for typical SLC beam parameters. With 3.5 10{sup 10} particles per pulse, bunch length of 0.8 mm and beam sizes of 2.1 {mu}m horizontally and 0.55 {mu}m vertically, the measured vertical size can be as much as 25% bigger than the real one. Furthermore during the collision the spot size actually decrease, producing an enhancement factor H{sub D} of about 1.25. This would yield to a true luminosity which is 1.6 times that which is estimated from the beam-beam deflection fit.

Disruption effects on the beam size measurement

International Nuclear Information System (INIS)

Raimondi, P.; Decker, F.J.; Chen, P.

1995-01-01

At the SLC Final Focus with higher currents and smaller beam sizes, the disruption parameter D y is close to one and so the pinch effect should produce a luminosity enhancement. Since a flat beam-beam function is fit to deflection scan data to measure the beam size, disruption can affect the measurement. Here the authors discuss the quantitative effects of disruption for typical SLC beam parameters. With 3.5 10 10 particles per pulse, bunch length of 0.8 mm and beam sizes of 2.1 μm horizontally and 0.55 μm vertically, the measured vertical size can be as much as 25% bigger than the real one. Furthermore during the collision the spot size actually decrease, producing an enhancement factor H D of about 1.25. This would yield to a true luminosity which is 1.6 times that which is estimated from the beam-beam deflection fit

Temporal variation in population size of European bird species: effects of latitude and marginality of distribution.

Directory of Open Access Journals (Sweden)

José J Cuervo

Full Text Available In the Northern Hemisphere, global warming has been shown to affect animal populations in different ways, with southern populations in general suffering more from increased temperatures than northern populations of the same species. However, southern populations are also often marginal populations relative to the entire breeding range, and marginality may also have negative effects on populations. To disentangle the effects of latitude (possibly due to global warming and marginality on temporal variation in population size, we investigated European breeding bird species across a latitudinal gradient. Population size estimates were regressed on years, and from these regressions we obtained the slope (a proxy for population trend and the standard error of the estimate (SEE (a proxy for population fluctuations. The possible relationships between marginality or latitude on one hand and slopes or SEE on the other were tested among populations within species. Potentially confounding factors such as census method, sampling effort, density-dependence, habitat fragmentation and number of sampling years were controlled statistically. Population latitude was positively related to regression slopes independent of marginality, with more positive slopes (i.e., trends in northern than in southern populations. The degree of marginality was positively related to SEE independent of latitude, with marginal populations showing larger SEE (i.e., fluctuations than central ones. Regression slopes were also significantly related to our estimate of density-dependence and SEE was significantly affected by the census method. These results are consistent with a scenario in which southern and northern populations of European bird species are negatively affected by marginality, with southern populations benefitting less from global warming than northern populations, thus potentially making southern populations more vulnerable to extinction.

Size effects on failure behaviour of reactor pressure vessel steel and their dependence on deformation inhomogeneity

International Nuclear Information System (INIS)

Aktaa, J.; Klotz, M.; Schmitt, R.

2003-01-01

The investigation of the size dependence of the material behaviour and particularly of the failure strain is the main objective of the European research project LISSAC (Limit Strains for Severe Accident Conditions). Within our activities in LISSAC, tensile test series with specimens of similar geometry and different sizes are performed. The specimens, cut from the wall of a real reactor vessel, are flat with a central hole, flat with a double edge notch as well as round with a circumferential notch in order to obtain inhomogeneous deformation with high strain gradients, which will be higher in the smaller specimens and might be responsible for size effects. An additional variation of the strain gradient is obtained by varying the central hole radius of the flat specimens, with three different hole geometries being considered: round hole, increased round hole and slot. During the tests optical methods are used for measuring local deformations and partly local strain gradients. The results obtained show a size effect neither on the global nor on the local deformation behaviour, whereas the damage and failure behaviour is influenced significantly by the size of the specimen. On the basis of the surface deformation measurements, finite element calculations are performed to estimate the local failure strains as well as the corresponding strain gradients. A clear dependence of local failure strains on strain gradients is obtained. (author)

Effect of display size on visual attention.

Science.gov (United States)

Chen, I-Ping; Liao, Chia-Ning; Yeh, Shih-Hao

2011-06-01

Attention plays an important role in the design of human-machine interfaces. However, current knowledge about attention is largely based on data obtained when using devices of moderate display size. With advancement in display technology comes the need for understanding attention behavior over a wider range of viewing sizes. The effect of display size on test participants' visual search performance was studied. The participants (N = 12) performed two types of visual search tasks, that is, parallel and serial search, under three display-size conditions (16 degrees, 32 degrees, and 60 degrees). Serial, but not parallel, search was affected by display size. In the serial task, mean reaction time for detecting a target increased with the display size.

Effect of particle size distribution on sintering of tungsten

International Nuclear Information System (INIS)

Patterson, B.R.; Griffin, J.A.

1984-01-01

To date, very little is known about the effect of the nature of the particle size distribution on sintering. It is reasonable that there should be an effect of size distribution, and theory and prior experimental work examining the effects of variations in bimodal and continuous distributions have shown marked effects on sintering. Most importantly, even with constant mean particle size, variations in distribution width, or standard deviation, have been shown to produce marked variations in microstructure and sintering rate. In the latter work, in which spherical copper powders were blended to produce lognormal distributions of constant geometric mean particle size by weight frequency, blends with larger values of geometric standard deviation, 1nσ, sintered more rapidly. The goals of the present study were to examine in more detail the effects of variations in the width of lognormal particle size distributions of tungsten powder and determine the effects of 1nσ on the microstructural evolution during sintering

Influence of grain size and upper critical magnetic field on global pinning force of bronze-processed Nb/sub 3/Sn compound

International Nuclear Information System (INIS)

Ochiai, S.; Osamura, K.

1986-01-01

In order to know the dependency of global pinning force of Nb/sub 3/Sn compound on grain size and upper critical magnetic field, the global pinning force was measured at 3-15 T using bronze-processed multifilamentary composites. The grain size and upper critical magnetic field were varied by two types of annealing treatment: one is the isothermal annealing at 873, 973 and 1073 K up to 1730 ks and another is the two-stage annealing (low temperature annealing to form fine grains at 873 K for 1730 ks + high temperature annealing to raise upper critical magnetic field at 1073 K up to 18 ks). In the case of isothermal annealing treatment, both of grain size and upper critical magnetic field increased with increasing annealing temperature and time except for the annealing treatments at high temperature for prolonged times. In the case of two-stage annealing, both of them increased with second stage annealing time. The increase in grain size led to decrease in the pinning force but the increase in upper critical magnetic field to increase in it. From the analysis of the present data based on the Suenaga's speculation concerning with the density of pinning site and the Kramer's equation, it was suggested that the pinning force is, to a first approximation, proportional to the product of inverse grain size and (1-h)/sup 2/h/sup 1/2/ where h is the reduced magnetic field

FIRM SIZE EFFECTS ON TRANSACTION COSTS

NARCIS (Netherlands)

NOOTEBOOM, B

1993-01-01

Associated with effects of scale, scope, experience and learning there are effects of firm size on transaction costs; in the stages of contact, contract and control. These effects are due to ''threshold costs'' in setting up contacts, contracts and governance schemes, and to differences with respect

Sustainable Sizing.

Science.gov (United States)

Robinette, Kathleen M; Veitch, Daisy

2016-08-01

To provide a review of sustainable sizing practices that reduce waste, increase sales, and simultaneously produce safer, better fitting, accommodating products. Sustainable sizing involves a set of methods good for both the environment (sustainable environment) and business (sustainable business). Sustainable sizing methods reduce (1) materials used, (2) the number of sizes or adjustments, and (3) the amount of product unsold or marked down for sale. This reduces waste and cost. The methods can also increase sales by fitting more people in the target market and produce happier, loyal customers with better fitting products. This is a mini-review of methods that result in more sustainable sizing practices. It also reviews and contrasts current statistical and modeling practices that lead to poor fit and sizing. Fit-mapping and the use of cases are two excellent methods suited for creating sustainable sizing, when real people (vs. virtual people) are used. These methods are described and reviewed. Evidence presented supports the view that virtual fitting with simulated people and products is not yet effective. Fit-mapping and cases with real people and actual products result in good design and products that are fit for person, fit for purpose, with good accommodation and comfortable, optimized sizing. While virtual models have been shown to be ineffective for predicting or representing fit, there is an opportunity to improve them by adding fit-mapping data to the models. This will require saving fit data, product data, anthropometry, and demographics in a standardized manner. For this success to extend to the wider design community, the development of a standardized method of data collection for fit-mapping with a globally shared fit-map database is needed. It will enable the world community to build knowledge of fit and accommodation and generate effective virtual fitting for the future. A standardized method of data collection that tests products' fit methodically

Development of neural basis for chinese orthographic neighborhood size effect.

Science.gov (United States)

Zhao, Jing; Li, Qing-Lin; Ding, Guo-Sheng; Bi, Hong-Yan

2016-02-01

The brain activity of orthographic neighborhood size (N size) effect in Chinese character naming has been studied in adults, meanwhile behavioral studies have revealed a developmental trend of Chinese N-size effect in developing readers. However, it is unclear whether and how the neural mechanism of N-size effect changes in Chinese children along with development. Here we address this issue using functional magnetic resonance imaging. Forty-four students from the 3(rd) , 5(th) , and 7(th) grades were scanned during silent naming of Chinese characters. After scanning, all participants took part in an overt naming test outside the scanner, and results of the naming task showed that the 3(rd) graders named characters from large neighborhoods faster than those from small neighborhoods, revealing a facilitatory N-size effect; the 5(th) graders showed null N-size effect while the 7(th) graders showed an inhibitory N-size effect. Neuroimaging results revealed that only the 3(rd) graders exhibited a significant N-size effect in the left middle occipital activity, with greater activation for large N-size characters. Results of 5(th) and 7(th) graders showed significant N-size effects in the left middle frontal gyrus, in which 5(th) graders induced greater activation in large N-size condition than in small N-size condition, while 7(th) graders exhibited an opposite effect which was similar to the adult pattern reported in a previous study. The current findings suggested the transition from broadly tuned to finely tuned orthographic representation with reading development, and the inhibition from neighbors' phonology for higher graders. Hum Brain Mapp 37:632-647, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Effect Size in Efficacy Trials of Women With Decreased Sexual Desire.

Science.gov (United States)

Pyke, Robert E; Clayton, Anita H

2018-03-22

Regarding hypoactive sexual desire disorder (HSDD) in women, some reviewers judge the effect size small for medications vs placebo, but substantial for cognitive behavior therapy (CBT) or mindfulness meditation training (MMT) vs wait list. However, we lack comparisons of the effect sizes for the active intervention itself, for the control treatment, and for the differential between the two. For efficacy trials of HSDD in women, compare effect sizes for medications (testosterone/testosterone transdermal system, flibanserin, and bremelanotide) and placebo vs effect sizes for psychotherapy and wait-list control. We conducted a literature search for mean changes and SD on main measures of sexual desire and associated distress in trials of medications, CBT, or MMT. Effect size was used as it measures the magnitude of the intervention without confounding by sample size. Cohen d was used to determine effect sizes. For medications, mean (SD) effect size was 1.0 (0.34); for CBT and MMT, 1.0 (0.36); for placebo, 0.55 (0.16); and for wait list, 0.05 (0.26). Recommendations of psychotherapy over medication for treatment of HSDD are premature and not supported by data on effect sizes. Active participation in treatment conveys considerable non-specific benefits. Caregivers should attend to biological and psychosocial elements, and patient preference, to optimize response. Few clinical trials of psychotherapies were substantial in size or utilized adequate control paradigms. Medications and psychotherapies had similar, large effect sizes. Effect size of placebo was moderate. Effect size of wait-list control was very small, about one quarter that of placebo. Thus, a substantial non-specific therapeutic effect is associated with receiving placebo plus active care and evaluation. The difference in effect size between placebo and wait-list controls distorts the value of the subtraction of effect of the control paradigms to estimate intervention effectiveness. Pyke RE, Clayton AH

The global atmospheric electric circuit and its effects on cloud microphysics

International Nuclear Information System (INIS)

Tinsley, B A

2008-01-01

circuit variations. The theory for electrical effects on scavenging of aerosols in clouds is reviewed, with several microphysical processes having consequences for contact ice nucleation; effects on droplet size distributions; precipitation and cloud lifetimes. There are several pathways for resulting macroscopic cloud changes that affect atmospheric circulation; including enhanced ice production and precipitation from clouds in cyclonic storms, with latent heat release affecting cyclone vorticity; and cloud cover changes in layer clouds that affect the atmospheric radiation balance. These macroscopic consequences of global circuit variability affecting aerosols-cloud interactions provide explanations for the many observations of short term and long term changes in clouds and climate that correlate with measured or inferred J z and cosmic ray flux changes due to external or internal forcing, and lead to predictions of additional effects

The global atmospheric electric circuit and its effects on cloud microphysics

Energy Technology Data Exchange (ETDEWEB)

Tinsley, B A [Physics Department and Center for Space Sciences, WT15, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX, 75080-3021 (United States)], E-mail: Tinsley@UTDallas.edu

2008-06-15

inferred global circuit variations. The theory for electrical effects on scavenging of aerosols in clouds is reviewed, with several microphysical processes having consequences for contact ice nucleation; effects on droplet size distributions; precipitation and cloud lifetimes. There are several pathways for resulting macroscopic cloud changes that affect atmospheric circulation; including enhanced ice production and precipitation from clouds in cyclonic storms, with latent heat release affecting cyclone vorticity; and cloud cover changes in layer clouds that affect the atmospheric radiation balance. These macroscopic consequences of global circuit variability affecting aerosols-cloud interactions provide explanations for the many observations of short term and long term changes in clouds and climate that correlate with measured or inferred J{sub z} and cosmic ray flux changes due to external or internal forcing, and lead to predictions of additional effects.

The Role of Social Norms in the Portion Size Effect: Reducing normative relevance reduces the effect of portion size on consumption decisions

Directory of Open Access Journals (Sweden)

Iris eVersluis

2016-05-01

Full Text Available People typically eat more from large portions of food than from small portions. An explanation that has often been given for this so-called portion size effect is that the portion size acts as a social norm and as such communicates how much is appropriate to eat. In this paper, we tested this explanation by examining whether manipulating the relevance of the portion size as a social norm changes the portion size effect, as assessed by prospective consumption decisions. We conducted one pilot experiment and one full experiment in which participants respectively indicated how much they would eat or serve themselves from a given amount of different foods. In the pilot (N = 63, we manipulated normative relevance by allegedly basing the portion size on the behavior of either students of the own university (in-group or of another university (out-group. In the main experiment (N = 321, we told participants that either a minority or majority of people similar to them approved of the portion size. Results show that in both experiments, participants expected to serve themselves and to eat more from larger than from smaller portions. As expected, however, the portion size effect was less pronounced when the reference portions were allegedly based on the behavior of an out-group (pilot or approved only by a minority (main experiment. These findings suggest that the portion size indeed provides normative information, because participants were less influenced by it if it communicated the behaviors or values of a less relevant social group. In addition, in the main experiment, the relation between portion size and the expected amount served was partially mediated by the amount that was considered appropriate, suggesting that concerns about eating an appropriate amount indeed play a role in the portion size effect. However, since the portion size effect was weakened but not eliminated by the normative relevance manipulations and since mediation was only partial

The effect of harmonized emissions on aerosol properties in global models – an AeroCom experiment

Directory of Open Access Journals (Sweden)

C. Textor

2007-08-01

Full Text Available The effects of unified aerosol sources on global aerosol fields simulated by different models are examined in this paper. We compare results from two AeroCom experiments, one with different (ExpA and one with unified emissions, injection heights, and particle sizes at the source (ExpB. Surprisingly, harmonization of aerosol sources has only a small impact on the simulated inter-model diversity of the global aerosol burden, and consequently global optical properties, as the results are largely controlled by model-specific transport, removal, chemistry (leading to the formation of secondary aerosols and parameterizations of aerosol microphysics (e.g., the split between deposition pathways and to a lesser extent by the spatial and temporal distributions of the (precursor emissions.

The burdens of black carbon and especially sea salt become more coherent in ExpB only, because the large ExpA diversities for these two species were caused by a few outliers. The experiment also showed that despite prescribing emission fluxes and size distributions, ambiguities in the implementation in individual models can lead to substantial differences.

These results indicate the need for a better understanding of aerosol life cycles at process level (including spatial dispersal and interaction with meteorological parameters in order to obtain more reliable results from global aerosol simulations. This is particularly important as such model results are used to assess the consequences of specific air pollution abatement strategies.

Family size and effective population size in a hatchery stock of coho salmon (Oncorhynchus kisutch)

Science.gov (United States)

Simon, R.C.; McIntyre, J.D.; Hemmingsen, A.R.

1986-01-01

Means and variances of family size measured in five year-classes of wire-tagged coho salmon (Oncorhynchus kisutch) were linearly related. Population effective size was calculated by using estimated means and variances of family size in a 25-yr data set. Although numbers of age 3 adults returning to the hatchery appeared to be large enough to avoid inbreeding problems (the 25-yr mean exceeded 4500), the numbers actually contributing to the hatchery production may be too low. Several strategies are proposed to correct the problem perceived. Argument is given to support the contention that the problem of effective size is fairly general and is not confined to the present study population.

Measuring wage effects of plant size

DEFF Research Database (Denmark)

Albæk, Karsten; Arai, Mahmood; Asplund, Rita

1998-01-01

There are large plant size–wage effects in the Nordic countries after taking into account individual and job characteristics as well as systematical sorting of the workers into various plant-sizes. The plant size–wage elasticities we obtain are, in contrast to other dimensions of the wage distrib......–wage elasticity. Our results indicate that using size–class midpoints yields essentially the same results as using exact measures of plant size...

EFFECTS OF GLOBAL WARMING

OpenAIRE

Dr. Basanti Jain

2017-01-01

The abnormal increase in the concentration of the greenhouse gases is resulting in higher temperatures. We call this effect is global warming. The average temperature around the world has increased about 1'c over 140 years, 75% of this has risen just over the past 30 years. The solar radiation, as it reaches the earth, produces "greenhouse effect" in the atmosphere. The thick atmospheric layers over the earth behaves as a glass surface, as it permits short wave radiations from coming in, but ...

Size-effects in porous metals

DEFF Research Database (Denmark)

Niordson, Christian Frithiof; Tvergaard, Viggo

The intrinsic size-effect for porous metals is investigated. The analyses are carried out numerically using a finite strain generalization of a higher order strain gradient plasticity model. Results for plane strain growth of cylindrical voids are presented in terms of response curves and curves...

Size-effects in porous metals

DEFF Research Database (Denmark)

Niordson, Christian Frithiof; Tvergaard, Viggo

2007-01-01

The intrinsic size-effect for porous metals is investigated. The analyses are carried out numerically using a finite strain generalization of a higher order strain gradient plasticity model. Results for plane strain growth of cylindrical voids are presented in terms of response curves and curves...

The Effects of Globalization on Developing Economies: The ...

African Journals Online (AJOL)

This paper examines globalization and its effects on third World Economic ... Corruption due to bad government has become the order of the day as workers strive to ... or eliminate the negative effect of globalization and to domain the positive side of ... AJOL's Partners · Terms and Conditions of Use · Contact AJOL · News.

The effect of sadness on global-local processing.

Science.gov (United States)

von Mühlenen, Adrian; Bellaera, Lauren; Singh, Amrendra; Srinivasan, Narayanan

2018-05-04

Gable and Harmon-Jones (Psychological Science, 21(2), 211-215, 2010) reported that sadness broadens attention in a global-local letter task. This finding provided the key test for their motivational intensity account, which states that the level of spatial processing is not determined by emotional valence, but by motivational intensity. However, their finding is at odds with several other studies, showing no effect, or even a narrowing effect of sadness on attention. This paper reports two attempts to replicate the broadening effect of sadness on attention. Both experiments used a global-local letter task, but differed in terms of emotion induction: Experiment 1 used the same pictures as Gable and Harmon-Jones, taken from the IAPS dataset; Experiment 2 used a sad video underlaid with sad music. Results showed a sadness-specific global advantage in the error rates, but not in the reaction times. The same null results were also found in a South-Asian sample in both experiments, showing that effects on global/local processing were not influenced by a culturally related processing bias.

Global climate: Methane contribution to greenhouse effect

International Nuclear Information System (INIS)

Metalli, P.

1992-01-01

The global atmospheric concentration of methane greatly contributes to the severity of the greenhouse effect. It has been estimated that this concentration, due mainly to human activities, is growing at the rate of roughly 1.1% per year. Environmental scientists suggest that a reduction, even as small as 10%, in global methane emissions would be enough to curtail the hypothetical global warning scenarios forecasted for the up-coming century. Through the recovery of methane from municipal and farm wastes, as well as, through the control of methane leaks and dispersions in coal mining and petrochemical processes, substantial progress towards the abatement of greenhouse gas effects could be achieved without having to resort to economically detrimental limitations on the use of fossil fuels

What big size you have! Using effect sizes to determine the impact of public health nursing interventions.

Science.gov (United States)

Johnson, K E; McMorris, B J; Raynor, L A; Monsen, K A

2013-01-01

The Omaha System is a standardized interface terminology that is used extensively by public health nurses in community settings to document interventions and client outcomes. Researchers using Omaha System data to analyze the effectiveness of interventions have typically calculated p-values to determine whether significant client changes occurred between admission and discharge. However, p-values are highly dependent on sample size, making it difficult to distinguish statistically significant changes from clinically meaningful changes. Effect sizes can help identify practical differences but have not yet been applied to Omaha System data. We compared p-values and effect sizes (Cohen's d) for mean differences between admission and discharge for 13 client problems documented in the electronic health records of 1,016 young low-income parents. Client problems were documented anywhere from 6 (Health Care Supervision) to 906 (Caretaking/parenting) times. On a scale from 1 to 5, the mean change needed to yield a large effect size (Cohen's d ≥ 0.80) was approximately 0.60 (range = 0.50 - 1.03) regardless of p-value or sample size (i.e., the number of times a client problem was documented in the electronic health record). Researchers using the Omaha System should report effect sizes to help readers determine which differences are practical and meaningful. Such disclosures will allow for increased recognition of effective interventions.

A global analysis of the urban heat island effect based on multisensor satellite data

Science.gov (United States)

Xiao, J.; Frolking, S. E.; Milliman, T. E.; Schneider, A.; Friedl, M. A.

2017-12-01

Human population is rapidly urbanizing. In much of the world, cities are prone to hotter weather than surrounding rural areas - so-called `urban heat islands' - and this effect can have mortal consequences during heat waves. During the daytime, when the surface energy balance is driven by incoming solar radiation, the magnitude of urban warming is strongly influenced by surface albedo and the capacity to evaporate water (i.e., there is a strong relationship between vegetated land fraction and the ratio of sensible to latent heat loss or Bowen ratio). At nighttime, urban cooling is often inhibited by the thermal inertia of the built environment and anthropogenic heat exhaust from building and transportation energy use. We evaluated a suite of global remote sensing data sets representing a range of urban characteristics against MODIS-derived land-surface temperature differences between urban and surrounding rural areas. We included two new urban datasets in this analysis - MODIS-derived change in global urban extent and global urban microwave backscatter - along with several MODIS standard products and DMSP/OLS nighttime lights time series data. The global analysis spanned a range of urban characteristics that likely influence the magnitude of daytime and/or nighttime urban heat islands - urban size, population density, building density, state of development, impervious fraction, eco-climatic setting. Specifically, we developed new satellite datasets and synthesizing these with existing satellite data into a global database of urban land surface parameters, used two MODIS land surface temperature products to generate time series of daytime and nighttime urban heat island effects for 30 large cities across the globe, and empirically analyzed these data to determine specifically which remote sensing-based characterizations of global urban areas have explanatory power with regard to both daytime and nighttime urban heat islands.

Effect of micro-computed tomography voxel size and segmentation method on trabecular bone microstructure measures in mice

Directory of Open Access Journals (Sweden)

Blaine A. Christiansen

2016-12-01

Full Text Available Micro-computed tomography (μCT is currently the gold standard for determining trabecular bone microstructure in small animal models. Numerous parameters associated with scanning and evaluation of μCT scans can strongly affect morphologic results obtained from bone samples. However, the effect of these parameters on specific trabecular bone outcomes is not well understood. This study investigated the effect of μCT scanning with nominal voxel sizes between 6–30 μm on trabecular bone outcomes quantified in mouse vertebral body trabecular bone. Additionally, two methods for determining a global segmentation threshold were compared: based on qualitative assessment of 2D images, or based on quantitative assessment of image histograms. It was found that nominal voxel size had a strong effect on several commonly reported trabecular bone parameters, in particular connectivity density, trabecular thickness, and bone tissue mineral density. Additionally, the two segmentation methods provided similar trabecular bone outcomes for scans with small nominal voxel sizes, but considerably different outcomes for scans with larger voxel sizes. The Qualitatively Selected segmentation method more consistently estimated trabecular bone volume fraction (BV/TV and trabecular thickness across different voxel sizes, but the Histogram segmentation method more consistently estimated trabecular number, trabecular separation, and structure model index. Altogether, these results suggest that high-resolution scans be used whenever possible to provide the most accurate estimation of trabecular bone microstructure, and that the limitations of accurately determining trabecular bone outcomes should be considered when selecting scan parameters and making conclusions about inter-group variance or between-group differences in studies of trabecular bone microstructure in small animals. Keywords: Trabecular bone, Microstructure, Micro-computed tomography, Voxel size, Resolution

A descriptive study of effect-size reporting in research reviews.

Science.gov (United States)

Floyd, Judith A

2017-06-01

To describe effect-size reporting in research reviews completed in support of evidence-based practice in nursing. Many research reviews report nurses' critical appraisal of level, quality and overall strength of evidence available to address clinical questions. Several studies of research-review quality suggest effect-size information would be useful to include in these reviews, but none focused on reviewers' attention to effect sizes. Descriptive. One hundred and four reviews indexed in CINAHL as systematic reviews and published from July 2012-February 2014 were examined. Papers were required to be peer-reviewed, written in English, contain an abstract and have at least one nurse author. Reviews were excluded if they did not use critical appraisal methods to address evidence of correlation, prediction or effectiveness. Data from remaining papers (N = 73) were extracted by three or more independent coders using a structured coding form and detailed codebook. Data were stored, viewed and analysed using Microsoft Office Excel ® spreadsheet functions. Sixteen percent (n = 12) of the sample contained effect-size information. Of the 12, six included all the effect-size information recommended by APA guidelines. Independent of completeness of reporting, seven contained discussion of effect sizes in the paper, but none included effect-size information in abstracts. Research reviews available to practicing nurses often fail to include information needed to accurately assess how much improvement may result from implementation of evidence-based policies, programs, protocols or practices. Manuscript reviewers are urged to hold authors to APA standards for reporting/discussing effect-size information in both primary research reports and research reviews. © 2016 John Wiley & Sons Ltd.

The evolution of biomass-burning aerosol size distributions due to coagulation: dependence on fire and meteorological details and parameterization

Directory of Open Access Journals (Sweden)

K. M. Sakamoto

2016-06-01

Full Text Available Biomass-burning aerosols have a significant effect on global and regional aerosol climate forcings. To model the magnitude of these effects accurately requires knowledge of the size distribution of the emitted and evolving aerosol particles. Current biomass-burning inventories do not include size distributions, and global and regional models generally assume a fixed size distribution from all biomass-burning emissions. However, biomass-burning size distributions evolve in the plume due to coagulation and net organic aerosol (OA evaporation or formation, and the plume processes occur on spacial scales smaller than global/regional-model grid boxes. The extent of this size-distribution evolution is dependent on a variety of factors relating to the emission source and atmospheric conditions. Therefore, accurately accounting for biomass-burning aerosol size in global models requires an effective aerosol size distribution that accounts for this sub-grid evolution and can be derived from available emission-inventory and meteorological parameters. In this paper, we perform a detailed investigation of the effects of coagulation on the aerosol size distribution in biomass-burning plumes. We compare the effect of coagulation to that of OA evaporation and formation. We develop coagulation-only parameterizations for effective biomass-burning size distributions using the SAM-TOMAS large-eddy simulation plume model. For the most-sophisticated parameterization, we use the Gaussian Emulation Machine for Sensitivity Analysis (GEM-SA to build a parameterization of the aged size distribution based on the SAM-TOMAS output and seven inputs: emission median dry diameter, emission distribution modal width, mass emissions flux, fire area, mean boundary-layer wind speed, plume mixing depth, and time/distance since emission. This parameterization was tested against an independent set of SAM-TOMAS simulations and yields R2 values of 0.83 and 0.89 for Dpm and modal width

The evolution of biomass-burning aerosol size distributions due to coagulation: dependence on fire and meteorological details and parameterization

Science.gov (United States)

Sakamoto, Kimiko M.; Laing, James R.; Stevens, Robin G.; Jaffe, Daniel A.; Pierce, Jeffrey R.

2016-06-01

Biomass-burning aerosols have a significant effect on global and regional aerosol climate forcings. To model the magnitude of these effects accurately requires knowledge of the size distribution of the emitted and evolving aerosol particles. Current biomass-burning inventories do not include size distributions, and global and regional models generally assume a fixed size distribution from all biomass-burning emissions. However, biomass-burning size distributions evolve in the plume due to coagulation and net organic aerosol (OA) evaporation or formation, and the plume processes occur on spacial scales smaller than global/regional-model grid boxes. The extent of this size-distribution evolution is dependent on a variety of factors relating to the emission source and atmospheric conditions. Therefore, accurately accounting for biomass-burning aerosol size in global models requires an effective aerosol size distribution that accounts for this sub-grid evolution and can be derived from available emission-inventory and meteorological parameters. In this paper, we perform a detailed investigation of the effects of coagulation on the aerosol size distribution in biomass-burning plumes. We compare the effect of coagulation to that of OA evaporation and formation. We develop coagulation-only parameterizations for effective biomass-burning size distributions using the SAM-TOMAS large-eddy simulation plume model. For the most-sophisticated parameterization, we use the Gaussian Emulation Machine for Sensitivity Analysis (GEM-SA) to build a parameterization of the aged size distribution based on the SAM-TOMAS output and seven inputs: emission median dry diameter, emission distribution modal width, mass emissions flux, fire area, mean boundary-layer wind speed, plume mixing depth, and time/distance since emission. This parameterization was tested against an independent set of SAM-TOMAS simulations and yields R2 values of 0.83 and 0.89 for Dpm and modal width, respectively. The

Size effects in lithium ion batteries

International Nuclear Information System (INIS)

Yao Hu-Rong; Yin Ya-Xia; Guo Yu-Gao

2016-01-01

Size-related properties of novel lithium battery materials, arising from kinetics, thermodynamics, and newly discovered lithium storage mechanisms, are reviewed. Complementary experimental and computational investigations of the use of the size effects to modify electrodes and electrolytes for lithium ion batteries are enumerated and discussed together. Size differences in the materials in lithium ion batteries lead to a variety of exciting phenomena. Smaller-particle materials with highly connective interfaces and reduced diffusion paths exhibit higher rate performance than the corresponding bulk materials. The thermodynamics is also changed by the higher surface energy of smaller particles, affecting, for example, secondary surface reactions, lattice parameter, voltage, and the phase transformation mechanism. Newly discovered lithium storage mechanisms that result in superior storage capacity are also briefly highlighted. (topical review)

How organizational and global factors condition the effects of energy efficiency on CO_2 emission rebounds among the world's power plants

International Nuclear Information System (INIS)

Grant, Don; Jorgenson, Andrew K.; Longhofer, Wesley

2016-01-01

The United Nations Intergovernmental Panel on Climate Change (IPCC), the International Energy Agency (IEA), and several nations suggest that energy efficiency is an effective strategy for reducing energy consumption and associated greenhouse gas emissions. Skeptics contend that because efficiency lowers the price of energy and energy services, it may actually increase demand for them, causing total emissions to rise. While both sides of this debate have researched the magnitude of these so-called rebound effects among end-use consumers, researchers have paid less attention to the conditions under which direct rebounds cause CO_2 emissions to rise among industrial producers. In particular, researchers have yet to explore how organizational and global factors might condition the effects of efficiency on emissions among power plants, the world's most concentrated sources of anthropogenic greenhouse gases. Here we use a unique dataset containing nearly every fossil-fuel power plant in the world to determine whether the impact of efficiency on emissions varies by plants' age, size, and location in global economic and normative systems. Findings reveal that each of these factors has a significant interaction with efficiency and thus shapes environmentally destructive rebound effects. - Highlights: •Skeptics charge that energy efficiency may actually cause CO_2 emissions to rise. •Few have examined whether such rebound effects occur among power plants. •Little also known about whether plants' organizational and global characteristics condition rebounds. •Conduct first analysis of rebound effects among the world's power plants. •Rebounds found to depend on plants' age, size, and location in international economic and normative systems.

When Globalization Hits Home

DEFF Research Database (Denmark)

Borrás, Susana; Haakonsson, Stine Jessen

Lead firms are increasingly reorganizing their innovation activities into global innovation networks. Such reorganization has potentially major impact on their existing home-based innovation networks. Based on 31 interviews in four case studies of lead firms in the Danish food industry, the paper...... analyzes the dynamics of five key features of home-based innovation networks: 1) size of the national networks, 2) type of organization, 3) content of collaboration within the network, 4) concurrent globalization of organizations in the network, and 5) degree of formalization of network interactions....... The dynamics are generally differentiated according to the type of lead firm strategy, i.e. knowledge augmenting or knowledge exploiting. The qualitative and exploratory findings point towards some effects on national innovation networks. Hence, the paper concludes by hypothesizing that the globalization...

Hall measurements and grain-size effects in polycrystalline silicon

International Nuclear Information System (INIS)

Ghosh, A.K.; Rose, A.; Maruska, H.P.; Eustace, D.J.; Feng, T.

1980-01-01

The effects of grain size on Hall measurements in polycrystalline silicon are analyzed and interpreted, with some modifications, using the model proposed by Bube. This modified model predicts that the measured effective Hall voltage is composed of components originating from the bulk and space-charge regions. For materials with large grain sizes, the carrier concentration is independent of the intergrain boundary barrier, whereas the mobility is dependent on it. However, for small grains, both the carrier density and mobility depend on the barrier. These predictions are consistent with experimental results of mm-size Wacker and μm-size neutron-transmutation-doped polycrystalline silicon

The Effect of Land Use (Deforestation) on Global Changing and its consequences in Turkey

Science.gov (United States)

Onursal Denli, G.; Denli, H. H.

2015-12-01

Land use has generally been considered as a local environmental issue, but it is becoming a force of global importance. Global changes to forests, farmlands, waterways, and air are being driven by the need to provide food, water and shelter to more than six billion people. Global croplands, pastures, plantations and urban areas have expanded in recent decades, accompanied by large increases in energy, water and fertilizer consumption, along with considerable losses of biodiversity. Especially the forests influence climate through physical, chemical and biological processes that affect planetary energetics, the hydrologic cycle, and atmospheric composition. Such changes in land use have enabled humans to appropriate an increasing share of the planet's resources, but they also potentially undermine the capacity of ecosystems to sustain food production, maintain freshwater and forest resources, regulate climate and air quality. Global Warming and Climate Change are the two main fundamental problems facing Turkey as well as the World. The expedition and size of this change is becoming noticeably conspicuous now. According to the International Union for Conservation of Nature (IUCN), the global temperature has been increased of about 0.74 degree Celsius since the Industrial Revolution. Interdisciplinary science that integrates knowledge of the many interacting climate services of forests with the impacts of global change is necessary to identify and understand as yet unexplored feedbacks in the Earth system and the potential of forests to mitigate climate change. The general scientific opinions on the climate change states that in the past 50 years, global warming has effected the human life resulting with very obvious influences. High rates of deforestation within a country are most commonly linked to population growth and poverty. In Turkey, the forests are destroyed for various reasons resulting to a change in the climate. This study examines the causes of

Effect of Reiki therapy on pain and anxiety in adults: an in-depth literature review of randomized trials with effect size calculations.

Science.gov (United States)

Thrane, Susan; Cohen, Susan M

2014-12-01

The objective of this study was to calculate the effect of Reiki therapy for pain and anxiety in randomized clinical trials. A systematic search of PubMed, ProQuest, Cochrane, PsychInfo, CINAHL, Web of Science, Global Health, and Medline databases was conducted using the search terms pain, anxiety, and Reiki. The Center for Reiki Research also was examined for articles. Studies that used randomization and a control or usual care group, used Reiki therapy in one arm of the study, were published in 2000 or later in peer-reviewed journals in English, and measured pain or anxiety were included. After removing duplicates, 49 articles were examined and 12 articles received full review. Seven studies met the inclusion criteria: four articles studied cancer patients, one examined post-surgical patients, and two analyzed community dwelling older adults. Effect sizes were calculated for all studies using Cohen's d statistic. Effect sizes for within group differences ranged from d = 0.24 for decrease in anxiety in women undergoing breast biopsy to d = 2.08 for decreased pain in community dwelling adults. The between group differences ranged from d = 0.32 for decrease of pain in a Reiki versus rest intervention for cancer patients to d = 4.5 for decrease in pain in community dwelling adults. Although the number of studies is limited, based on the size Cohen's d statistics calculated in this review, there is evidence to suggest that Reiki therapy may be effective for pain and anxiety. Continued research using Reiki therapy with larger sample sizes, consistently randomized groups, and standardized treatment protocols is recommended. Copyright © 2014 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

Globalization : Countries, Cities and Multinationals

NARCIS (Netherlands)

McCann, Philip; Acs, Zoltan J.

2011-01-01

McCann P. and Acs Z. J. Globalization: countries, cities and multinationals, Regional Studies. This paper explores the relationship between the size of a country, the size of its cities, and the importance of economies of scale in the modern era of globalization. In order to do this, it integrates

Effects of sample size on the second magnetization peak in ...

Indian Academy of Sciences (India)

the sample size decreases – a result that could be interpreted as a size effect in the order– disorder vortex matter phase transition. However, local magnetic measurements trace this effect to metastable disordered vortex states, revealing the same order–disorder transition induction in samples of different size. Keywords.

Global radiative effects of solid fuel cookstove aerosol emissions

Science.gov (United States)

Huang, Yaoxian; Unger, Nadine; Storelvmo, Trude; Harper, Kandice; Zheng, Yiqi; Heyes, Chris

2018-04-01

We apply the NCAR CAM5-Chem global aerosol-climate model to quantify the net global radiative effects of black and organic carbon aerosols from global and Indian solid fuel cookstove emissions for the year 2010. Our assessment accounts for the direct radiative effects, changes to cloud albedo and lifetime (aerosol indirect effect, AIE), impacts on clouds via the vertical temperature profile (semi-direct effect, SDE) and changes in the surface albedo of snow and ice (surface albedo effect). In addition, we provide the first estimate of household solid fuel black carbon emission effects on ice clouds. Anthropogenic emissions are from the IIASA GAINS ECLIPSE V5a inventory. A global dataset of black carbon (BC) and organic aerosol (OA) measurements from surface sites and aerosol optical depth (AOD) from AERONET is used to evaluate the model skill. Compared with observations, the model successfully reproduces the spatial patterns of atmospheric BC and OA concentrations, and agrees with measurements to within a factor of 2. Globally, the simulated AOD agrees well with observations, with a normalized mean bias close to zero. However, the model tends to underestimate AOD over India and China by ˜ 19 ± 4 % but overestimate it over Africa by ˜ 25 ± 11 % (± represents modeled temporal standard deviations for n = 5 run years). Without BC serving as ice nuclei (IN), global and Indian solid fuel cookstove aerosol emissions have net global cooling radiative effects of -141 ± 4 mW m-2 and -12 ± 4 mW m-2, respectively (± represents modeled temporal standard deviations for n = 5 run years). The net radiative impacts are dominated by the AIE and SDE mechanisms, which originate from enhanced cloud condensation nuclei concentrations for the formation of liquid and mixed-phase clouds, and a suppression of convective transport of water vapor from the lower troposphere to the upper troposphere/lower stratosphere that in turn leads to reduced ice cloud formation. When BC is allowed

Maximum weight of greenhouse effect to global temperature variation

International Nuclear Information System (INIS)

Sun, Xian; Jiang, Chuangye

2007-01-01

Full text: The global average temperature has risen by 0.74 0 C since the late 19th century. Many studies have concluded that the observed warming in the last 50 years may be attributed to increasing concentrations of anthropogenic greenhouse gases. But some scientists have a different point of view. Global climate change is affected not only by anthropogenic activities, but also constraints in climate system natural factors. How much is the influencing weight of C02's greenhouse effects to the global temperature variation? Does global climate continue warming or decreasing in the next 20 years? They are two hot spots in global climate change. The multi-timescales analysis method - Empirical mode decomposition (EMD) is used to diagnose global annual mean air temperature dataset for land surface provided by IPCC and atmospheric content of C02 provided by the Carbon Dioxide Information Analysis Center (CDIAC) during 1881-2002. The results show that: Global temperature variation contains quasi-periodic oscillations on four timescales (3 yr, 6 yr, 20 yr and 60 yr, respectively) and a century-scale warming trend. The variance contribution of IMF1-IMF4 and trend is 17.55%, 11.34%, 6.77%, 24.15% and 40.19%, respectively. The trend and quasi-60 yr oscillation of temperature variation are the most prominent; C02's greenhouse effect on global temperature variation is mainly century-scale trend. The contribution of C02 concentration to global temperature variability is not more than 40.19%, whereas 59.81% contribution to global temperature variation is non-greenhouse effect. Therefore, it is necessary to re-study the dominant factors that induce the global climate change; It has been noticed that on the periods of 20 yr and 60 yr oscillation, the global temperature is beginning to decreased in the next 20 years. If the present C02 concentration is maintained, the greenhouse effect will be too small to countercheck the natural variation in global climate cooling in the next 20

State Support: A Prerequisite for Global Health Network Effectiveness

Science.gov (United States)

Marten, Robert; Smith, Richard D.

2018-01-01

Shiffman recently summarized lessons for network effectiveness from an impressive collection of case-studies. However, in common with most global health governance analysis in recent years, Shiffman underplays the important role of states in these global networks. As the body which decides and signs international agreements, often provides the resourcing, and is responsible for implementing initiatives all contributing to the prioritization of certain issues over others, state recognition and support is a prerequisite to enabling and determining global health networks’ success. The role of states deserves greater attention, analysis and consideration. We reflect upon the underappreciated role of the state within the current discourse on global health. We present the tobacco case study to illustrate the decisive role of states in determining progress for global health networks, and highlight how states use a legitimacy loop to gain legitimacy from and provide legitimacy to global health networks. Moving forward in assessing global health networks’ effectiveness, further investigating state support as a determinant of success will be critical. Understanding how global health networks and states interact and evolve to shape and support their respective interests should be a focus for future research. PMID:29524958

Size effects in nanoindentation: an experimental and analytical study

NARCIS (Netherlands)

Voyiadjis, G.Z.; Peters, Rick

2009-01-01

This work addresses the size effect encountered in nanoindentation experiments. It is generally referred to as the indentation size effect (ISE). Classical descriptions of the ISE show a decrease in hardness for increasing indentation depth. Recently new experiments have shown that after the initial

Does neighborhood size really cause the word length effect?

Science.gov (United States)

Guitard, Dominic; Saint-Aubin, Jean; Tehan, Gerald; Tolan, Anne

2018-02-01

In short-term serial recall, it is well-known that short words are remembered better than long words. This word length effect has been the cornerstone of the working memory model and a benchmark effect that all models of immediate memory should account for. Currently, there is no consensus as to what determines the word length effect. Jalbert and colleagues (Jalbert, Neath, Bireta, & Surprenant, 2011a; Jalbert, Neath, & Surprenant, 2011b) suggested that neighborhood size is one causal factor. In six experiments we systematically examined their suggestion. In Experiment 1, with an immediate serial recall task, multiple word lengths, and a large pool of words controlled for neighborhood size, the typical word length effect was present. In Experiments 2 and 3, with an order reconstruction task and words with either many or few neighbors, we observed the typical word length effect. In Experiment 4 we tested the hypothesis that the previous abolition of the word length effect when neighborhood size was controlled was due to a confounded factor: frequency of orthographic structure. As predicted, we reversed the word length effect when using short words with less frequent orthographic structures than the long words, as was done in both of Jalbert et al.'s studies. In Experiments 5 and 6, we again observed the typical word length effect, even if we controlled for neighborhood size and frequency of orthographic structure. Overall, the results were not consistent with the predictions of Jalbert et al. and clearly showed a large and reliable word length effect after controlling for neighborhood size.

Introduction to global energetic problems

International Nuclear Information System (INIS)

Gicquel, R.

1992-01-01

This book gives a view on global energetic problems and proposes a thorough economic analysis on principle aspects taken into account: energy supply, depending energy sources and available technologic channels, relationships between macro-economy and energy demand, new size of energy problems (environmental effects, overcosts of renewable energy sources, necessity of an high technologic development...). 38 refs

Size effect in barium titanate powders synthesized by different hydrothermal methods

International Nuclear Information System (INIS)

Sun Weian

2006-01-01

The size effect in barium titanate (BaTiO 3 ) was investigated both experimentally and theoretically. Tetragonal BaTiO 3 powders with average sizes from 80 to 420 nm were directly prepared by different hydrothermal methods. The tetragonality of the hydrothermal BaTiO 3 decreased with decreasing particle size, which exhibited a dependence on the synthesis method. A phenomenological model for the size effect was proposed to interpret the experimental observations. The influence of the defects, mainly the lattice hydroxyl, on the size effect was investigated to understand the correlation between the size effect and synthesis condition. The permittivities of BaTiO 3 powder at different particle sizes were calculated, which predicted a maximum permittivity of over 16 000 around the room-temperature critical size of ∼70 nm. The prediction was in good accordance with the experimental data reported recently

Effects of global warming on floods and droughts in the Caribbean

International Nuclear Information System (INIS)

Narayan, Kailas

2004-01-01

The Caribbean islands stretch in an arc from Cuba, south of Florida, to Trinidad and Tobago, north of the South American coast. The islands range in size from 100,000 square kilometers to 100 square kilometers, with populations ranging from ten million to less than ten thousand people. There is a wide range of rainfall in the region, occurring mainly from the Inter-Tropical convergence Zone, Tropical Waves and Hurricanes. There are also extended periods of droughts in the dry season. As a result the islands suffer from droughts as well as floods. These phenomena can have devastating results on the economies of the islands, resulting in extreme hardships for the population as well as forced shifting of population centers. Change of precipitation patterns as a result of Global warming can only worsen the situation. In this paper the author attempts an investigation into the effects of global warming and the resulting impacts in terms of droughts, floods on the Caribbean islands and on coastal areas of continental countries in the Caribbean. Vulnerability and risks are also investigated in terms of these phenomena. (Author)

Application of global rainbow technique in sprays with a dependence of the refractive index on droplet size

Science.gov (United States)

Saengkaew, S.; Bodoc, V.; Lavergne, G.; Grehan, G.

2013-01-01

In liquid combustion, the evaporation process is one of the key parameters which controls combustion efficiency. To understand the combustion process, and to be able to develop an efficient combustor which produces less pollutant, it is necessary to be able to measure evaporation properties. Several techniques exist to measure the physical properties of fuel droplets, but very few exist to measure the thermo-chemical properties. The global rainbow technique (GRT) has been proposed and successfully used to measure the average temperature and the size distribution of sprays under the assumption that all the droplets are at the same temperature. This paper explores the applicability of GRT to sprays where the refractive index is a function of the particle size. A first result proves that the refractive index measured by GRT is weighted by the droplet diameter to the power of 7/3. This result permits accurate and fast comparisons between the numerical simulations and the experiments. A second result is the measurement of the refractive index by the size class by coupling GRT and Phase Doppler Anemometry (PDA) measurements (or another measurement technique with a low sensitivity to the refractive index such as holography, diffractometry, etc).

The characteristics of Chinese orthographic neighborhood size effect for developing readers.

Directory of Open Access Journals (Sweden)

Jing Zhao

Full Text Available Orthographic neighborhood size (N size effect in Chinese character naming has been studied in adults. In the present study, we aimed to explore the developmental characteristics of Chinese N size effect. One hundred and seventeen students (40 from the 3(rd grade with mean age of 9 years; 40 from the 5(th grade with mean age of 11 years; 37 from the 7(th grade with mean age of 13 years were recruited in the study. A naming task of Chinese characters was adopted to elucidate N-size- effect development. Reaction times and error rates were recorded. Results showed that children in the 3(rd grade named characters from large neighborhoods faster than named those from small neighborhoods, revealing a facilitatory N size effect; the 5(th graders showed null N size effect; while the 7(th graders showed an inhibitory N size effect, with longer reaction times for the characters from large neighborhoods than for those from small neighborhoods. The change from facilitation to inhibition of neighborhood size effect across grades suggested the transition from broadly tuned to finely tuned lexical representation in reading development, and the possible inhibition from higher frequency neighbors for higher graders.

GLOBALIZATION AND ITS EFFECTS ON THE BANKING MANAGEMENT

Directory of Open Access Journals (Sweden)

Drăgan (Sântămărian Oana Raluca

2012-12-01

Full Text Available This paper describes one of the major challenges of the present: globalization and its effects on the banking. Globalization is now increasingly recognized as central to the growth of market economies. For the banking sector, this represents both a demand as well as a new landscape of business opportunity.Several years ago, the main part of the banks did not consider the globalization problems relevant for their operations. Recently, the banks began to realize the major impact of the globalization over the way of creating the banking risk in the future. The banking management in the context of globalization represents one of the challengesof these days. Starting from literature in the globalization field in this paper focuses on several relevant issues related to banking management.

Specimen size effects in Charpy impact testing

International Nuclear Information System (INIS)

Alexander, D.J.; Klueh, R.L.

1989-01-01

Full-size , half-size, and third-size specimens from several different steels have been tested as part of an ongoing alloy development program. The smaller specimens permit more specimens to be made from small trail heats and are much more efficient for irradiation experiments. The results of several comparisons between the different specimen sizes have shown that the smaller specimens show qualitatively similar behavior to large specimens, although the upper-shelf energy level and ductile-to-ductile transition temperature are reduced. The upper-shelf energy levels from different specimen sizes can be compared by using a simple volume normalization method. The effect of specimen size and geometry on the ductile-to-ductile transition temperature is more difficult to predict, although the available data suggest a simple shift in the transition temperature due to specimen size changes.The relatively shallower notch used in smaller specimens alters the deformation pattern, and permits yielding to spread back to the notched surface as well as through to the back. This reduces the constraint and the peak stresses, and thus the initiation of cleavage is more difficult. A better understanding of the stress and strain distributions is needed. 19 refs., 3 figs., 3 tabs

Bottom-up and top-down attentional contributions to the size congruity effect.

Science.gov (United States)

Sobel, Kenith V; Puri, Amrita M; Faulkenberry, Thomas J

2016-07-01

The size congruity effect refers to the interaction between the numerical and physical (i.e., font) sizes of digits in a numerical (or physical) magnitude selection task. Although various accounts of the size congruity effect have attributed this interaction to either an early representational stage or a late decision stage, only Risko, Maloney, and Fugelsang (Attention, Perception, & Psychophysics, 75, 1137-1147, 2013) have asserted a central role for attention. In the present study, we used a visual search paradigm to further study the role of attention in the size congruity effect. In Experiments 1 and 2, we showed that manipulating top-down attention (via the task instructions) had a significant impact on the size congruity effect. The interaction between numerical and physical size was larger for numerical size comparison (Exp. 1) than for physical size comparison (Exp. 2). In the remaining experiments, we boosted the feature salience by using a unique target color (Exp. 3) or by increasing the display density by using three-digit numerals (Exps. 4 and 5). As expected, a color singleton target abolished the size congruity effect. Searching for three-digit targets based on numerical size (Exp. 4) resulted in a large size congruity effect, but search based on physical size (Exp. 5) abolished the effect. Our results reveal a substantial role for top-down attention in the size congruity effect, which we interpreted as support for a shared-decision account.

Effects of grain size evolution on mantle dynamics

Science.gov (United States)

Schulz, Falko; Tosi, Nicola; Plesa, Ana-Catalina; Breuer, Doris

2016-04-01

The rheology of planetary mantle materials is strongly dependent on temperature, pressure, strain-rate, and grain size. In particular, the rheology of olivine, the most abundant mineral of the Earth's upper mantle, has been extensively studied in the laboratory (e.g., Karato and Wu, 1993; Hirth and Kohlstedt, 2003). Two main mechanisms control olivine's deformation: dislocation and diffusion creep. While the former implies a power-law dependence of the viscosity on the strain-rate that leads to a non-Newtonian behaviour, the latter is sensitively dependent on the grain size. The dynamics of planetary interiors is locally controlled by the deformation mechanism that delivers the lowest viscosity. Models of the dynamics and evolution of planetary mantles should thus be capable to self-consistently distinguish which of the two mechanisms dominates at given conditions of temperature, pressure, strain-rate and grain size. As the grain size can affect the viscosity associated with diffusion creep by several orders of magnitude, it can strongly influence the dominant deformation mechanism. The vast majority of numerical, global-scale models of mantle convection, however, are based on the use of a linear diffusion-creep rheology with constant grain-size. Nevertheless, in recent studies, a new equation has been proposed to properly model the time-dependent evolution of the grain size (Austin and Evens, 2007; Rozel et al., 2010). We implemented this equation in our mantle convection code Gaia (Hüttig et al., 2013). In the framework of simple models of stagnant lid convection, we compared simulations based on the fully time-dependent equation of grain-size evolution with simulations based on its steady-state version. In addition, we tested a number of different parameters in order to identify those that affects the grain size to the first order and, in turn, control the conditions at which mantle deformation is dominated by diffusion or dislocation creep. References Austin

Effect size calculation in meta-analyses of psychotherapy outcome research.

Science.gov (United States)

Hoyt, William T; Del Re, A C

2018-05-01

Meta-analysis of psychotherapy intervention research normally examines differences between treatment groups and some form of comparison group (e.g., wait list control; alternative treatment group). The effect of treatment is normally quantified as a standardized mean difference (SMD). We describe procedures for computing unbiased estimates of the population SMD from sample data (e.g., group Ms and SDs), and provide guidance about a number of complications that may arise related to effect size computation. These complications include (a) incomplete data in research reports; (b) use of baseline data in computing SMDs and estimating the population standard deviation (σ); (c) combining effect size data from studies using different research designs; and (d) appropriate techniques for analysis of data from studies providing multiple estimates of the effect of interest (i.e., dependent effect sizes). Clinical or Methodological Significance of this article: Meta-analysis is a set of techniques for producing valid summaries of existing research. The initial computational step for meta-analyses of research on intervention outcomes involves computing an effect size quantifying the change attributable to the intervention. We discuss common issues in the computation of effect sizes and provide recommended procedures to address them.

Simulation of finite size effects of the fiber bundle model

Science.gov (United States)

Hao, Da-Peng; Tang, Gang; Xun, Zhi-Peng; Xia, Hui; Han, Kui

2018-01-01

In theory, the macroscopic fracture of materials should correspond with the thermodynamic limit of the fiber bundle model. However, the simulation of a fiber bundle model with an infinite size is unrealistic. To study the finite size effects of the fiber bundle model, fiber bundle models of various size are simulated in detail. The effects of system size on the constitutive behavior, critical stress, maximum avalanche size, avalanche size distribution, and increased step number of external load are explored. The simulation results imply that there is no feature size or cut size for macroscopic mechanical and statistical properties of the model. The constitutive curves near the macroscopic failure for various system size can collapse well with a simple scaling relationship. Simultaneously, the introduction of a simple extrapolation method facilitates the acquisition of more accurate simulation results in a large-limit system, which is better for comparison with theoretical results.

Group-size effect on scanning behaviour of Maasai Ostrich Struthio ...

African Journals Online (AJOL)

Group-size effect on scanning behaviour of Maasai Ostrich Struthio camelus ... minute) among different group sizes in late 2006 in Serengeti National Park, ... be influenced by factors other than group size, such as body size and habitat type.

Do Effect-Size Measures Measure up?: A Brief Assessment

Science.gov (United States)

Onwuegbuzie, Anthony J.; Levin, Joel R.; Leech, Nancy L.

2003-01-01

Because of criticisms leveled at statistical hypothesis testing, some researchers have argued that measures of effect size should replace the significance-testing practice. We contend that although effect-size measures have logical appeal, they are also associated with a number of limitations that may result in problematic interpretations of them…

Finite size effects in the intermittency analysis of the fragment-size correlations

International Nuclear Information System (INIS)

Bozek, P.; Ploszajczak, M.; Tucholski, A.

1991-01-01

An influence of the finite size effect on the fragment-size correlations in the nuclear multifragmentation is studied using the method of scaled factorial moments for a 1 - dim percolation model and for a statistical model of the fragmentation process, which for a certain value of a tuning parameter yields the power-law behaviour of the fragment-size distribution. It is shown that the statistical models of this type contain only repulsive correlations due to the conservation laws. The comparison of the results with those obtained in the non-critical 1 - dim percolation and in the 3 - dim percolation at around the critical point is presented. Correlations in the 1 - dim percolation model are analysed analytically and the mechanism of the attractive correlations in 1 - dim and 3 - dim is identified. (author) 30 refs., 7 figs

A global off-line model of size-resolved aerosol microphysics: I. Model development and prediction of aerosol properties

Directory of Open Access Journals (Sweden)

D. V. Spracklen

2005-01-01

Full Text Available A GLObal Model of Aerosol Processes (GLOMAP has been developed as an extension to the TOMCAT 3-D Eulerian off-line chemical transport model. GLOMAP simulates the evolution of the global aerosol size distribution using a sectional two-moment scheme and includes the processes of aerosol nucleation, condensation, growth, coagulation, wet and dry deposition and cloud processing. We describe the results of a global simulation of sulfuric acid and sea spray aerosol. The model captures features of the aerosol size distribution that are well established from observations in the marine boundary layer and free troposphere. Modelled condensation nuclei (CN>3nm vary between about 250–500 cm-3 in remote marine boundary layer regions and are generally in good agreement with observations. Modelled continental CN concentrations are lower than observed, which may be due to lack of some primary aerosol sources or the neglect of nucleation mechanisms other than binary homogeneous nucleation of sulfuric acid-water particles. Remote marine CN concentrations increase to around 2000–10 000 cm (at standard temperature and pressure in the upper troposphere, which agrees with typical observed vertical profiles. Cloud condensation nuclei (CCN at 0.2% supersaturation vary between about 1000 cm-3 in polluted regions and between 10 and 500 cm-3 in the remote marine boundary layer. New particle formation through sulfuric acid-water binary nucleation occurs predominantly in the upper troposphere, but the model results show that these particles contribute greatly to aerosol concentrations in the marine boundary layer. For this sulfur-sea salt system it is estimated that sea spray emissions account for only ~10% of CCN in the tropical marine boundary layer, but between 20 and 75% in the mid-latitude Southern Ocean. In a run with only natural sulfate and sea salt emissions the global mean surface CN concentration is more than 60% of that from a run with 1985 anthropogenic

Size effects in fcc crystals during the high rate compression test

International Nuclear Information System (INIS)

Yaghoobi, Mohammadreza; Voyiadjis, George Z.

2016-01-01

The present work studies the different mechanisms of size effects in fcc metallic samples of confined volumes during high rate compression tests using large scale atomistic simulation. Different mechanisms of size effects, including the dislocation starvation, source exhaustion, and dislocation source length effect are investigated for pillars with different sizes. The results show that the controlling mechanisms of size effects depend only on the pillar size and not on the value of applied strain. Dislocation starvation is the governing mechanism for very small pillars, i.e. pillars with diameters less than 30 nm. Increasing the pillar size, the dislocation exhaustion mechanism becomes active and there is no more source-limited activations. Next, the average dislocation source length is obtained and compared for pillars with different sizes. The results show that in the case of high rate deformations, the source length does not depend on the sample size, and the related size effects mechanisms are not active anymore. Also, in the case of high rate deformations, there are no size effects for pristine pillars with the diameters larger than 135 nm. In other words, increasing the strain rate decreases the pillar size at which there is no more size effects in the absence of strain gradient. The governing mechanisms of plastic deformation at high strain rate experiments are also different from those of the quasi-static tests. First, the diameter in which the dislocation nucleation at the free surface becomes the dominant mechanism changes from around 200 nm–30 nm. Next, in the case of the pillars with larger diameters, the plastic deformation is governed by the cross-slip instead of the operation of truncated dislocation sources, which is dominant at slower rates of deformation. In order to study the effects of pillar initial structure on the controlling mechanism of size effects, an initial loading and unloading procedure is conducted on some samples prior to the

Local extinction and recolonization, species effective population size, and modern human origins.

Science.gov (United States)

Eller, Elise; Hawks, John; Relethford, John H

2004-10-01

A primary objection from a population genetics perspective to a multiregional model of modern human origins is that the model posits a large census size, whereas genetic data suggest a small effective population size. The relationship between census size and effective size is complex, but arguments based on an island model of migration show that if the effective population size reflects the number of breeding individuals and the effects of population subdivision, then an effective population size of 10,000 is inconsistent with the census size of 500,000 to 1,000,000 that has been suggested by archeological evidence. However, these models have ignored the effects of population extinction and recolonization, which increase the expected variance among demes and reduce the inbreeding effective population size. Using models developed for population extinction and recolonization, we show that a large census size consistent with the multiregional model can be reconciled with an effective population size of 10,000, but genetic variation among demes must be high, reflecting low interdeme migration rates and a colonization process that involves a small number of colonists or kin-structured colonization. Ethnographic and archeological evidence is insufficient to determine whether such demographic conditions existed among Pleistocene human populations, and further work needs to be done. More realistic models that incorporate isolation by distance and heterogeneity in extinction rates and effective deme sizes also need to be developed. However, if true, a process of population extinction and recolonization has interesting implications for human demographic history.

Effects of fuel particle size distributions on neutron transport in stochastic media

International Nuclear Information System (INIS)

Liang, Chao; Pavlou, Andrew T.; Ji, Wei

2014-01-01

Highlights: • Effects of fuel particle size distributions on neutron transport are evaluated. • Neutron channeling is identified as the fundamental reason for the effects. • The effects are noticeable at low packing and low optical thickness systems. • Unit cells of realistic reactor designs are studied for different size particles. • Fuel particle size distribution effects are not negligible in realistic designs. - Abstract: This paper presents a study of the fuel particle size distribution effects on neutron transport in three-dimensional stochastic media. Particle fuel is used in gas-cooled nuclear reactor designs and innovative light water reactor designs loaded with accident tolerant fuel. Due to the design requirements and fuel fabrication limits, the size of fuel particles may not be perfectly constant but instead follows a certain distribution. This brings a fundamental question to the radiation transport computation community: how does the fuel particle size distribution affect the neutron transport in particle fuel systems? To answer this question, size distribution effects and their physical interpretations are investigated by performing a series of neutron transport simulations at different fuel particle size distributions. An eigenvalue problem is simulated in a cylindrical container consisting of fissile fuel particles with five different size distributions: constant, uniform, power, exponential and Gaussian. A total of 15 parametric cases are constructed by altering the fissile particle volume packing fraction and its optical thickness, but keeping the mean chord length of the spherical fuel particle the same at different size distributions. The tallied effective multiplication factor (k eff ) and the spatial distribution of fission power density along axial and radial directions are compared between different size distributions. At low packing fraction and low optical thickness, the size distribution shows a noticeable effect on neutron

Nature of size effects in compact models of field effect transistors

Energy Technology Data Exchange (ETDEWEB)

Torkhov, N. A., E-mail: trkf@mail.ru [Tomsk State University, Tomsk 634050 (Russian Federation); Scientific-Research Institute of Semiconductor Devices, Tomsk 634050 (Russian Federation); Tomsk State University of Control Systems and Radioelectronics, Tomsk 634050 (Russian Federation); Babak, L. I.; Kokolov, A. A.; Salnikov, A. S.; Dobush, I. M. [Tomsk State University of Control Systems and Radioelectronics, Tomsk 634050 (Russian Federation); Novikov, V. A., E-mail: novikovvadim@mail.ru; Ivonin, I. V. [Tomsk State University, Tomsk 634050 (Russian Federation)

2016-03-07

Investigations have shown that in the local approximation (for sizes L < 100 μm), AlGaN/GaN high electron mobility transistor (HEMT) structures satisfy to all properties of chaotic systems and can be described in the language of fractal geometry of fractional dimensions. For such objects, values of their electrophysical characteristics depend on the linear sizes of the examined regions, which explain the presence of the so-called size effects—dependences of the electrophysical and instrumental characteristics on the linear sizes of the active elements of semiconductor devices. In the present work, a relationship has been established for the linear model parameters of the equivalent circuit elements of internal transistors with fractal geometry of the heteroepitaxial structure manifested through a dependence of its relative electrophysical characteristics on the linear sizes of the examined surface areas. For the HEMTs, this implies dependences of their relative static (A/mm, mA/V/mm, Ω/mm, etc.) and microwave characteristics (W/mm) on the width d of the sink-source channel and on the number of sections n that leads to a nonlinear dependence of the retrieved parameter values of equivalent circuit elements of linear internal transistor models on n and d. Thus, it has been demonstrated that the size effects in semiconductors determined by the fractal geometry must be taken into account when investigating the properties of semiconductor objects on the levels less than the local approximation limit and designing and manufacturing field effect transistors. In general, the suggested approach allows a complex of problems to be solved on designing, optimizing, and retrieving the parameters of equivalent circuits of linear and nonlinear models of not only field effect transistors but also any arbitrary semiconductor devices with nonlinear instrumental characteristics.

Computation of Effect Size for Moderating Effects of Categorical Variables in Multiple Regression

Science.gov (United States)

Aguinis, Herman; Pierce, Charles A.

2006-01-01

The computation and reporting of effect size estimates is becoming the norm in many journals in psychology and related disciplines. Despite the increased importance of effect sizes, researchers may not report them or may report inaccurate values because of a lack of appropriate computational tools. For instance, Pierce, Block, and Aguinis (2004)…

Effects of Seed Size on Germination and Early Morphorlogical and ...

African Journals Online (AJOL)

Effects of Seed Size on Germination and Early Morphorlogical and Physiological Characteristics of Gmelina Arborea , Roxb. ... African Research Review ... They were grouped into 3 categories as large seed size (LSS), medium seed size ...

Size effect of the elastic modulus of rectangular nanobeams: Surface elasticity effect

International Nuclear Information System (INIS)

Yao Hai-Yan; Fan Wen-Liang; Yun Guo-Hong

2013-01-01

The size-dependent elastic property of rectangular nanobeams (nanowires or nanoplates) induced by the surface elasticity effect is investigated by using a developed modified core-shell model. The effect of surface elasticity on the elastic modulus of nanobeams can be characterized by two surface related parameters, i.e., inhomogeneous degree constant and surface layer thickness. The analytical results show that the elastic modulus of the rectangular nanobeam exhibits a distinct size effect when its characteristic size reduces below 100 nm. It is also found that the theoretical results calculated by a modified core-shell model have more obvious advantages than those by other models (core-shell model and core-surface model) by comparing them with relevant experimental measurements and computational results, especially when the dimensions of nanostructures reduce to a few tens of nanometers. (condensed matter: structural, mechanical, and thermal properties)

Effect of particle size on thermal decomposition of alkali metal picrates

International Nuclear Information System (INIS)

Liu, Rui; Zhang, Tonglai; Yang, Li; Zhou, Zunning

2014-01-01

Graphical abstract: The smaller-sized picrate has greater gas emission than do its larger counterpart. The small size effect reduces the thermal decomposition activation energy, accelerates the reaction rate, and promotes the reaction activity. - Highlights: • Picrates were prepared into three micron sizes by microemulsion synthesis. • Thermal decomposition kinetics and thermodynamics were studied by DPTA and DSC. • Smaller-sized picrate has higher activity and faster reaction rate. • Particle size effect on thermal decomposition kinetics and thermodynamics was revealed. - Abstract: Three alkali metal picrates, KPA, RbPA and CsPA, were prepared into three micron sizes by microemulsion synthesis, and their thermal decomposition behaviors were investigated by DPTA at different temperatures and by DSC at different heating rates. The smaller-sized picrate has greater gas emission and smaller kinetic and thermodynamic parameters than do its larger counterpart. It can be attributed to the decreasing particle size which leads to the high surface energy, the fast mass and heat transfer, and the increasing active sites on the reaction interface. The small size effect and surface effect cause the autocatalysis which reduces the activation energy and promotes the reaction activity. The particle size does not affect the reaction mechanism. However, the picrates with different central alkali metals exhibit different reaction mechanisms even though they are of the same size. This is because the central metal determines the bond energy and consequently affects the stability of picrate

Effect of particle size on thermal decomposition of alkali metal picrates

Energy Technology Data Exchange (ETDEWEB)

Liu, Rui; Zhang, Tonglai, E-mail: ztlbit@bit.edu.cn; Yang, Li; Zhou, Zunning

2014-05-01

Graphical abstract: The smaller-sized picrate has greater gas emission than do its larger counterpart. The small size effect reduces the thermal decomposition activation energy, accelerates the reaction rate, and promotes the reaction activity. - Highlights: • Picrates were prepared into three micron sizes by microemulsion synthesis. • Thermal decomposition kinetics and thermodynamics were studied by DPTA and DSC. • Smaller-sized picrate has higher activity and faster reaction rate. • Particle size effect on thermal decomposition kinetics and thermodynamics was revealed. - Abstract: Three alkali metal picrates, KPA, RbPA and CsPA, were prepared into three micron sizes by microemulsion synthesis, and their thermal decomposition behaviors were investigated by DPTA at different temperatures and by DSC at different heating rates. The smaller-sized picrate has greater gas emission and smaller kinetic and thermodynamic parameters than do its larger counterpart. It can be attributed to the decreasing particle size which leads to the high surface energy, the fast mass and heat transfer, and the increasing active sites on the reaction interface. The small size effect and surface effect cause the autocatalysis which reduces the activation energy and promotes the reaction activity. The particle size does not affect the reaction mechanism. However, the picrates with different central alkali metals exhibit different reaction mechanisms even though they are of the same size. This is because the central metal determines the bond energy and consequently affects the stability of picrate.

Core size effects on safety performances of LMRs

Energy Technology Data Exchange (ETDEWEB)

Na, Byung Chan; Hahn, Do Hee [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1998-12-31

An oxide fuel small size core (1200 MWt) was analyzed in comparison with a large size core (3600 MWt) in order to evaluate the size effects on transient safety performances of liquid-metal reactors (LMRs). In the first part of the study, main static safety parameters (i.e., Doppler coefficient, sodium void effect, etc.) of the two cores were characterized, and the second part of the study was focused on the dynamic behavior of the cores in two representative transient events: the unprotected loss-of-flow (ULOF) and the unprotected transient overpower (UTOP). Margins to fuel melting and sodium boiling have been evaluated for these representative transients. Results show that the small core has a generally better or equivalent level of safety performances during these events. 6 refs., 4 figs., 2 tabs. (Author)

Core size effects on safety performances of LMRs

Energy Technology Data Exchange (ETDEWEB)

Na, Byung Chan; Hahn, Do Hee [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1997-12-31

An oxide fuel small size core (1200 MWt) was analyzed in comparison with a large size core (3600 MWt) in order to evaluate the size effects on transient safety performances of liquid-metal reactors (LMRs). In the first part of the study, main static safety parameters (i.e., Doppler coefficient, sodium void effect, etc.) of the two cores were characterized, and the second part of the study was focused on the dynamic behavior of the cores in two representative transient events: the unprotected loss-of-flow (ULOF) and the unprotected transient overpower (UTOP). Margins to fuel melting and sodium boiling have been evaluated for these representative transients. Results show that the small core has a generally better or equivalent level of safety performances during these events. 6 refs., 4 figs., 2 tabs. (Author)

Size effects in PbTiO3 nanocrystals: Effect of particle size on spontaneous polarization and strains

Science.gov (United States)

Akdogan, E. K.; Rawn, C. J.; Porter, W. D.; Payzant, E. A.; Safari, A.

2005-04-01

The spontaneous polarization (Ps) and spontaneous strains (xi) in mechanically unclamped and surface charge compensated PbTiO3 nanocrystals were determined as a function of particle size in the range <150nm by differential scanning calorimetry and x-ray powder diffraction, respectively. Significant deviations from bulk order parameters (P,xi) have been observed as the particle size decreased below ˜100nm. The critical size (rc) below which the ferroelectric tetragonal phase transforms to the paraelectric cubic phase was determined as ˜15nm. The depression in transition temperature with particle size is 14 °C at 28 nm. No change in the order of m3m →4mm ferrodistortive phase transition is observed. A simple analysis showed that ΔHtr/(kBT )˜103 at 25 °C for r =16nm, indicating that the stabilization of the cubic phase at rc cannot be linked to an instability in dipolar ordering due to thermal agitations. Comparison of the spontaneous volumetric strains with the strain induced by surface stress indicated that the effect of surface stress on ferroelectric phase stability was negligible. Anomalies in electrostrictive properties were determined for r →rc. The observed size dependence of PS is attributed to the reduced extent of long-range dipole-dipole interactions that arise due to the changes in bonding characteristics of ions with decreasing particle size in the perovskite lattice, in conformity with a recent study by Tsunekawa et al. [Phys. Rev. Lett. 85 (16), 4340 (2000)].

THE EFFECTS OF GLOBALIZATION IN NATIONAL ACCOUNTS

Directory of Open Access Journals (Sweden)

Clementina IVAN-UNGUREANU

2007-06-01

Full Text Available In the OECD Handbook on Economic Globalization, the term “globalization” is used to describe” the increasing internationalization of financial markets and of markets for goods and services. Globalization refers above all to a dynamic and multidimensional process of economic integration whereby national resources become more and more internationally mobile while national economies become increasingly interdependent.”Understanding globalization requires theory as well as facts, but certainly the facts are key ingredients in any assessment of this important phenomenon. Indeed, the facts are necessary to test the theories and to quantify the importance of what the theories predict.New concepts are emerging as economists address the issues of globalization and they need to be better defined and measured. In particular, there is a need for standard concepts and definitions in the area of globalization and its effects. Work under way internationally on SNA 93 rev 1 should help considerably in this regard. There is a pressing need for greater coordination and cooperation in this domain. This paper, presents some of the issues involved in measurement of the indicators of globalization and in using those indicators to quantify and describe the phenomenon and to evaluate its economic impact.

Application of a parallel genetic algorithm to the global optimization of medium-sized Au-Pd sub-nanometre clusters

Science.gov (United States)

Hussein, Heider A.; Demiroglu, Ilker; Johnston, Roy L.

2018-02-01

To contribute to the discussion of the high activity and reactivity of Au-Pd system, we have adopted the BPGA-DFT approach to study the structural and energetic properties of medium-sized Au-Pd sub-nanometre clusters with 11-18 atoms. We have examined the structural behaviour and stability as a function of cluster size and composition. The study suggests 2D-3D crossover points for pure Au clusters at 14 and 16 atoms, whereas pure Pd clusters are all found to be 3D. For Au-Pd nanoalloys, the role of cluster size and the influence of doping were found to be extensive and non-monotonic in altering cluster structures. Various stability criteria (e.g. binding energies, second differences in energy, and mixing energies) are used to evaluate the energetics, structures, and tendency of segregation in sub-nanometre Au-Pd clusters. HOMO-LUMO gaps were calculated to give additional information on cluster stability and a systematic homotop search was used to evaluate the energies of the generated global minima of mono-substituted clusters and the preferred doping sites, as well as confirming the validity of the BPGA-DFT approach.

Developing Global Leaders: Building Effective Global- Intercultural Collaborative Online Learning Environments

Science.gov (United States)

Ivy, Karen Lynne-Daniels

2017-01-01

This paper shares the findings of a study conducted on a virtual inter-cultural global leadership development learning project. Mixed Methods analysis techniques were used to examine the interviews of U.S. and Uganda youth project participants. The study, based on cultural and social constructivist learning theories, investigated the effects of…

R2 effect-size measures for mediation analysis.

Science.gov (United States)

Fairchild, Amanda J; Mackinnon, David P; Taborga, Marcia P; Taylor, Aaron B

2009-05-01

R(2) effect-size measures are presented to assess variance accounted for in mediation models. The measures offer a means to evaluate both component paths and the overall mediated effect in mediation models. Statistical simulation results indicate acceptable bias across varying parameter and sample-size combinations. The measures are applied to a real-world example using data from a team-based health promotion program to improve the nutrition and exercise habits of firefighters. SAS and SPSS computer code are also provided for researchers to compute the measures in their own data.

R2 effect-size measures for mediation analysis

Science.gov (United States)

Fairchild, Amanda J.; MacKinnon, David P.; Taborga, Marcia P.; Taylor, Aaron B.

2010-01-01

R2 effect-size measures are presented to assess variance accounted for in mediation models. The measures offer a means to evaluate both component paths and the overall mediated effect in mediation models. Statistical simulation results indicate acceptable bias across varying parameter and sample-size combinations. The measures are applied to a real-world example using data from a team-based health promotion program to improve the nutrition and exercise habits of firefighters. SAS and SPSS computer code are also provided for researchers to compute the measures in their own data. PMID:19363189

Effect of spatially correlated noise on stochastic synchronization in globally coupled FitzHugh-Nagumo neuron systems

Directory of Open Access Journals (Sweden)

Yange Shao

2014-01-01

Full Text Available The phenomenon of stochastic synchronization in globally coupled FitzHugh-Nagumo (FHN neuron system subjected to spatially correlated Gaussian noise is investigated based on dynamical mean-field approximation (DMA and direct simulation (DS. Results from DMA are in good quantitative or qualitative agreement with those from DS for weak noise intensity and larger system size. Whether the consisting single FHN neuron is staying at the resting state, subthreshold oscillatory regime, or the spiking state, our investigation shows that the synchronization ratio of the globally coupled system becomes higher as the noise correlation coefficient increases, and thus we conclude that spatial correlation has an active effect on stochastic synchronization, and the neurons can achieve complete synchronization in the sense of statistics when the noise correlation coefficient tends to one. Our investigation also discloses that the noise spatial correlation plays the same beneficial role as the global coupling strength in enhancing stochastic synchronization in the ensemble. The result might be useful in understanding the information coding mechanism in neural systems.

Effects of three global change drivers on terrestrial C:N:P stoichiometry

DEFF Research Database (Denmark)

Yue, Kai; Fornara, Dario A; Yang, Wanqin

2017-01-01

more common than synergistic or antagonistic interactions, (4) C:N:P stoichiometry of soil and soil microbial biomass shows high homeostasis under global change manipulations, and (5) C:N:P responses to global change are strongly affected by ecosystem type, local climate and experimental conditions......Over the last few decades there has been an increasing number of controlled-manipulative experiments to investigate how plants and soils might respond to global change. These experiments typically examined the effects of each of three global change drivers (i.e. nitrogen (N) deposition, warming...... of plants, soils and soil microbial biomass might respond to individual vs. combined effects of the three global change drivers. Our results show that (1) individual effects of N addition and elevated CO2 on C:N:P stoichiometry are stronger than warming, (2) combined effects of pairs of global change...

Zero Flow Global Ischemia-Induced Injuries in Rat Heart Are Attenuated by Natural Honey

Science.gov (United States)

Najafi, Moslem; Zahednezhad, Fahimeh; Samadzadeh, Mehrban; Vaez, Haleh

2012-01-01

Purpose: In the present study, effects of preischemic administration of natural honey on cardiac arrhythmias and myocardial infarction size during zero flow global ischemia were investigated in isolated rat heart. Methods: The isolated hearts were subjected to 30 min zero flow global ischemia followed by 120 min reperfusion then perfused by a modified drug free Krebs-Henseleit solution throughout the experiment (control) or the solution containing 0.25, 0.5, 1 and 2% of natural honey for 15 min before induction of global ischemia (treated groups), respectively. Cardiac arrhythmias were determined based on the Lambeth conventions and the infarct size was measured by computerized planimetry. Results: Myocardial infarction size was 55.8±7.8% in the control group, while preischemic perfusion of honey (0.25, 0.5, 1 and 2%) reduced it to 39.3±11, 30.6±5.5 (Phoney concentrations and infarction size reduction was observed (R2=0.9948). In addition, total number of ventricular ectopic beats were significantly decreased by all used concentrations of honey (PHoney (0.25, 0.5 and 1 %) also lowered incidence of irreversible ventricular fibrillation (Phoney treated groups. Conclusion: Preischemic administration of natural honey before zero flow global ischemia can protect isolated rat heart against ischemia/reperfusion injuries as reduction of infarction size and arrhythmias. Maybe, antioxidant and free radical scavenging activities of honey, reduction of necrotized tissue and providing energy sources may involve in these cardioprotective effects of honey. PMID:24312788

Why do they think nuclear power is origin of global warming effect?

International Nuclear Information System (INIS)

Fukae, Chiyokazu

2005-01-01

A questionnaire on nuclear power was conducted on 1500 adults in Kansai area, Japan, from October 9 to November 9, 2003. The recovery ratio was 71.0%. The results showed that 34% of them thought the nuclear power was protection of the global warming effect and 35% it was origin of the effect. It was analyzed by the logistic regression analysis method on whether the nuclear power was protection of global warming effect or not. About 43% of them recognized the nuclear power contributed to control carbon dioxide emission, and the mechanism of global warming effect. However, 35% of them did not recognize the mechanism and thought radioactive materials emission gave bad effects on the global environment. To make recognize the nuclear power is a good power source for protection of the global warming effect, the amount of reduction of carbon dioxide emission by nuclear power had to be shown. It is the shortest way for solution of the global warming problem to prove worthy of nuclear power's trust by safety and stable operation. (S.Y.)

Selection dramatically reduces effective population size in HIV-1 infection

Directory of Open Access Journals (Sweden)

Mittler John E

2008-05-01

Full Text Available Abstract Background In HIV-1 evolution, a 100–100,000 fold discrepancy between census size and effective population size (Ne has been noted. Although it is well known that selection can reduce Ne, high in vivo mutation and recombination rates complicate attempts to quantify the effects of selection on HIV-1 effective size. Results We use the inbreeding coefficient and the variance in allele frequency at a linked neutral locus to estimate the reduction in Ne due to selection in the presence of mutation and recombination. With biologically realistic mutation rates, the reduction in Ne due to selection is determined by the strength of selection, i.e., the stronger the selection, the greater the reduction. However, the dependence of Ne on selection can break down if recombination rates are very high (e.g., r ≥ 0.1. With biologically likely recombination rates, our model suggests that recurrent selective sweeps similar to those observed in vivo can reduce within-host HIV-1 effective population sizes by a factor of 300 or more. Conclusion Although other factors, such as unequal viral reproduction rates and limited migration between tissue compartments contribute to reductions in Ne, our model suggests that recurrent selection plays a significant role in reducing HIV-1 effective population sizes in vivo.

Global Warming: Understanding and Teaching the Forecast. Part A The Greenhouse Effect.

Science.gov (United States)

Andrews, Bill

1993-01-01

Provides information necessary for an interdisciplinary analysis of the greenhouse effect, enhanced greenhouse effect, global warming, global climate change, greenhouse gases, carbon dioxide, and scientific study of global warming for students grades 4-12. Several activity ideas accompany the information. (LZ)

Effect of particle size on the glass transition.

Science.gov (United States)

Larsen, Ryan J; Zukoski, Charles F

2011-05-01

The glass transition temperature of a broad class of molecules is shown to depend on molecular size. This dependency results from the size dependence of the pair potential. A generalized equation of state is used to estimate how the volume fraction at the glass transition depends on the size of the molecule, for rigid molecule glass-formers. The model shows that at a given pressure and temperature there is a size-induced glass transition: For molecules larger than a critical size, the volume fraction required to support the effective pressure due to particle attractions is above that which characterizes the glassy state. This observation establishes the boundary between nanoparticles, which exist in liquid form only as dispersions in low molecular weight solvents and large molecules which form liquids that have viscosities below those characterized by the glassy state.

Response trajectories capture the continuous dynamics of the size congruity effect.

Science.gov (United States)

Faulkenberry, Thomas J; Cruise, Alexander; Lavro, Dmitri; Shaki, Samuel

2016-01-01

In a comparison task involving numbers, the size congruity effect refers to the general finding that responses are usually faster when there is a match between numerical size and physical size (e.g., 2-8) than when there is a mismatch (e.g., 2-8). In the present study, we used computer mouse tracking to test two competing models of the size congruity effect: an early interaction model, where interference occurs at an early representational stage, and a late interaction model, where interference occurs as dynamic competition between response options. In three experiments, we found that the curvature of responses for incongruent trials was greater than for congruent trials. In Experiment 2 we showed that this curvature effect was reliably modulated by the numerical distance between the two stimulus numbers, with large distance pairs exhibiting a larger curvature effect than small distance pairs. In Experiment 3 we demonstrated that the congruity effects persist into response execution. These findings indicate that incongruities between numerical and physical sizes are carried throughout the response process and result from competition between parallel and partially active response options, lending further support to a late interaction model of the size congruity effect. Copyright © 2015 Elsevier B.V. All rights reserved.

Seasonal body size reductions with warming covary with major body size gradients in arthropod species

DEFF Research Database (Denmark)

Horne, Curtis R.; Hirst, Andrew G.; Atkinson, David

2017-01-01

experience different developmental conditions. Yet, unlike other size patterns, these common seasonal temperature–size gradients have never been collectively analysed. We undertake the largest analysis to date of seasonal temperature-size gradients in multivoltine arthropods, including 102 aquatic...... and terrestrial species from 71 global locations. Adult size declines in warmer seasons in 86% of the species examined. Aquatic species show approximately 2.5-fold greater reduction in size per °C of warming than terrestrial species, supporting the hypothesis that greater oxygen limitation in water than in air...

Are there links between responses of soil microbes and ecosystem functioning to elevated CO2, N deposition and warming? A global perspective.

Science.gov (United States)

García-Palacios, Pablo; Vandegehuchte, Martijn L; Shaw, E Ashley; Dam, Marie; Post, Keith H; Ramirez, Kelly S; Sylvain, Zachary A; de Tomasel, Cecilia Milano; Wall, Diana H

2015-04-01

In recent years, there has been an increase in research to understand how global changes' impacts on soil biota translate into altered ecosystem functioning. However, results vary between global change effects, soil taxa, and ecosystem processes studied, and a synthesis of relationships is lacking. Therefore, here we initiate such a synthesis to assess whether the effect size of global change drivers (elevated CO2, N deposition, and warming) on soil microbial abundance is related with the effect size of these drivers on ecosystem functioning (plant biomass, soil C cycle, and soil N cycle) using meta-analysis and structural equation modeling. For N deposition and warming, the global change effect size on soil microbes was positively associated with the global change effect size on ecosystem functioning, and these relationships were consistent across taxa and ecosystem processes. However, for elevated CO2, such links were more taxon and ecosystem process specific. For example, fungal abundance responses to elevated CO2 were positively correlated with those of plant biomass but negatively with those of the N cycle. Our results go beyond previous assessments of the sensitivity of soil microbes and ecosystem processes to global change, and demonstrate the existence of general links between the responses of soil microbial abundance and ecosystem functioning. Further we identify critical areas for future research, specifically altered precipitation, soil fauna, soil community composition, and litter decomposition, that are need to better quantify the ecosystem consequences of global change impacts on soil biodiversity. © 2014 John Wiley & Sons Ltd.

Finite-size effects on multibody neutrino exchange

CERN Document Server

Abada, A; Rodríguez-Quintero, J; Abada, As

1998-01-01

The effect of multibody massless neutrino exchanges between neutrons inside a finite-size neutron star is studied. We use an effective Lagrangian, which incorporates the effect of the neutrons on the neutrinos. Following Schwinger, it is shown that the total interaction energy density is computed by comparing the zero point energy of the neutrino sea with and without the star. It has already been shown that in an infinite-size star the total energy due to neutrino exchange vanishes exactly. The opposite claim that massless neutrino exchange would produce a huge energy is due to an improper summation of an infrared-divergent quantity. The same vanishing of the total energy has been proved exactly in the case of a finite star in a one-dimensional toy model. Here we study the three-dimensional case. We first consider the effect of a sharp star border, assumed to be a plane. We find that there is a non- vanishing of the zero point energy density difference between the inside and the outside due to the refraction ...

EU effect: Exporting emission standards for vehicles through the global market economy.

Science.gov (United States)

Crippa, M; Janssens-Maenhout, G; Guizzardi, D; Galmarini, S

2016-12-01

Emission data from EDGAR (Emissions Database for Global Atmospheric Research), rather than economic data, are used to estimate the effect of policies and of the global exports of policy-regulated goods, such as vehicles, on global emissions. The results clearly show that the adoption of emission standards for the road transport sector in the two main global markets (Europe and North America) has led to the global proliferation of emission-regulated vehicles through exports, regardless the domestic regulation in the country of destination. It is in fact more economically convenient for vehicle manufacturers to produce and sell a standard product to the widest possible market and in the greatest possible amounts. The EU effect (European Union effect) is introduced as a global counterpart to the California effect. The former is a direct consequence of the penetration of the EURO standards in the global markets by European and Japanese manufacturers, which effectively export the standard worldwide. We analyze the effect on PM 2.5 emissions by comparing a scenario of non-EURO standards against the current estimates provided by EDGAR. We find that PM 2.5 emissions were reduced by more than 60% since the 1990s worldwide. Similar investigations on other pollutants confirm the hypothesis that the combined effect of technological regulations and their diffusion through global markets can also produce a positive effect on the global environment. While we acknowledge the positive feedback, we also demonstrate that current efforts and standards will be totally insufficient should the passenger car fleets in emerging markets reach Western per capita figures. If emerging countries reach the per capita vehicle number of the USA and Europe under current technological conditions, then the world will suffer pre-1990 emission levels. Copyright © 2016 Elsevier Ltd. All rights reserved.

An Effect Size Measure for Raju's Differential Functioning for Items and Tests

Science.gov (United States)

Wright, Keith D.; Oshima, T. C.

2015-01-01

This study established an effect size measure for differential functioning for items and tests' noncompensatory differential item functioning (NCDIF). The Mantel-Haenszel parameter served as the benchmark for developing NCDIF's effect size measure for reporting moderate and large differential item functioning in test items. The effect size of…

Synthesis of nanometer-size inorganic materials for the examination of particle size effects on heterogeneous catalysis

Science.gov (United States)

Emerson, Sean Christian

The effect of acoustic and hydrodynamic cavitation on the precipitation of inorganic catalytic materials, specifically titania supported gold, was investigated. The overall objective was to understand the fundamental factors involved in synthesizing nanometer-size catalytic materials in the 1--10 nm range in a cavitating field. Materials with grain sizes in this range have been associated with enhanced catalytic activity compared to larger grain size materials. A new chemical approach was used to produce titania supported gold by co-precipitation with higher gold yields compared to other synthesis methods. Using this approach, it was determined that acoustic cavitation was unable to influence the gold mean crystallite size compared to non-sonicated catalysts. However, gold concentration on the catalysts was found to be very important for CO oxidation activity. By decreasing the gold concentration from a weight loading of 0.50% down to approximately 0.05%, the rate of reaction per mole of gold was found to increase by a factor of 19. Hydrodynamic cavitation at low pressures (6.9--48 bar) was determined to have no effect on gold crystallite size at a fixed gold content for the same precipitation technique used in the acoustic cavitation studies. By changing the chemistry of the precipitation system, however, it was found that a synergy existed between the dilution of the gold precursor solution, the orifice diameter, and the reducing agent addition rate. Individually, these factors were found to have little effect and only their interaction allowed gold grain size control in the range of 8--80 nm. Further modification of the system chemistry and the use of hydrodynamic cavitation at pressures in excess of 690 bar allowed the systematic control of gold crystallite size in the range of 2--9 nm for catalysts containing 2.27 +/- 0.17% gold. In addition, it was shown that the enhanced mixing due to cavitation led to larger gold yields compared to classical syntheses. The

Studying the effect of particle size and coating type on the blood kinetics of superparamagnetic iron oxide nanoparticles.

Science.gov (United States)

Roohi, Farnoosh; Lohrke, Jessica; Ide, Andreas; Schütz, Gunnar; Dassler, Katrin

2012-01-01

Magnetic resonance imaging (MRI), one of the most powerful imaging techniques available, usually requires the use of an on-demand designed contrast agent to fully exploit its potential. The blood kinetics of the contrast agent represent an important factor that needs to be considered depending on the objective of the medical examination. For particulate contrast agents, such as superparamagnetic iron oxide nanoparticles (SPIOs), the key parameters are particle size and characteristics of the coating material. In this study we analyzed the effect of these two properties independently and systematically on the magnetic behavior and blood half-life of SPIOs. Eleven different SPIOs were synthesized for this study. In the first set (a), seven carboxydextran (CDX)-coated SPIOs of different sizes (19-86 nm) were obtained by fractionating a broadly size-distributed CDX-SPIO. The second set (b) contained three SPIOs of identical size (50 nm) that were stabilized with different coating materials, polyacrylic acid (PAA), poly-ethylene glycol, and starch. Furthermore, small PAA-SPIOs (20 nm) were synthesized to gain a global insight into the effects of particle size vs coating characteristics. Saturation magnetization and proton relaxivity were determined to represent the magnetic and imaging properties. The blood half-life was analyzed in rats using MRI, time-domain nuclear magnetic resonance, and inductively coupled plasma optical emission spectrometry. By changing the particle size without modifying any other parameters, the relaxivity r(2) increased with increasing mean particle diameter. However, the blood half-life was shorter for larger particles. The effect of the coating material on magnetic properties was less pronounced, but it had a strong influence on blood kinetics depending on the ionic character of the coating material. In this report we systematically demonstrated that both particle size and coating material influence blood kinetics and magnetic properties of

THE EFFECT OF ILLICIT TRADE IN NARCOTICS ON GLOBAL ECONOMY

Directory of Open Access Journals (Sweden)

ALASMARI Khaled

2013-07-01

Illicit markets especially those dealing with narcotics constitute grievous issues to the world’s economies, putting to test global safety, economic progress as well as security and many other aspects. Seemingly, illicit narcotics trade in the last decade – that is 2000 to 2011 underwent a significant boom, resulting from a wide spectrum of illegal drugs such as cocaine as well as heroin among many other hard drugs. In today’s global society, several concerns are emerging on the rise of illicit narcotics trade accompanied with organized crime, chiefly as major hindrances to consistent global economic progress. Apparently, some of the effects of illicit narcotics trade are that; this trade gradually turns upside down business rules, opening way for new unruly market players besides reconfiguring influence in global economics as well as politics. Surprisingly, the revenue from illegal drugs in 2011 alone was roughly 10% of the global GDP. Hence, exaggerating local economies’ incomes and triggering ceaseless conflicts among market players, while at the same time reducing legal business activities likewise disintegrating socioeconomic conditions. An empirical research method was adopted for this study, analyzing illicit trade in narcotics on the global arena as from 2000 to 2011 and its resultant effects. The research findings indicate that, illegal drugs trade particularly on the world economy besides growing at a high rate, it endangers the overall welfare of humans likewise the business environment. This is ostensibly because this trade has high chances of engrossing regional economies into illegal drugs business activities, causing them to neglect sustainable ethical businesses. Now, to effectively address negative economic issues related to illegal drugs trade, there is apparent need for integrated efforts from local as well as international authorities. Such efforts are chiefly to control not only the harmful effects resulting from the use of illicit

Effects of anion size and concentration on electrolyte invasion into molecular-sized nanopores

International Nuclear Information System (INIS)

Liu Ling; Chen Xi; Kim, Taewan; Han Aijie; Qiao Yu

2010-01-01

When an electrolyte solution is pressurized into a molecular-sized nanopore, oppositely charged ions are strongly inclined to aggregate, which effectively reduces the ion solubility to zero. Inside the restrictive confinement, a unique quasi-periodic structure is formed where the paired ion couples are periodically separated by a number of water molecules. As the anion size or ion concentration varies, the geometrical characteristics of the confined ion structure would change considerably, leading to a significant variation in the transport pressure. Both experimental and simulation results indicate that, contradictory to the prediction of conventional theory, infiltration pressure decreases as the anions become larger.

Study of Cluster-size Effect on Damage Formation

International Nuclear Information System (INIS)

Aoki, Takaaki; Seki, Toshio; Nakai, Atsuko; Matsuo, Jiro; Takaoka, Gikan

2003-01-01

Computer simulation and experiments were performed in order to understand the effect of cluster size on damage formation. Results of molecular dynamics simulations of cluster impact on solid targets derived the model function, which explains the relationship among cluster size, incident energy and number of displacements. On the other hand, time of flight mass measurement system was installed a cluster irradiation system, so that cluster ion beam which cluster size distribution is well known can be irradiated on the target. The damage properties under various cluster irradiation conditions were examined using RBS. The results from computer simulations and experiments showed good agreements with each other, which suggests that irradiation damage by cluster ion beam can be controlled by selecting cluster size distribution and incident energy

Going global - growing small businesses

International Nuclear Information System (INIS)

Anderson, D.R.

1994-01-01

The Going Global Energy Steering Committee was established to help small and medium-sized Canadian enterprises to compete in the electrical power industry in the Asia-Pacific region primarily, but also in Eastern Europe and Latin America. The aim is to provide market intelligence, and help with forming consortia for financing. A small to medium-sized business can be defined as one with 50 to 500 employees. Big businesses no longer have the same competitive advantages that they once had, because automated systems can make short production runs just as cost-effective as long ones, and because computerization, automation and rising productivity mean that fewer workers are required than formerly

EFFECTS OF ULTRASOUND ON THE MORPHOLOGY, PARTICLE SIZE, CRYSTALLINITY, AND CRYSTALLITE SIZE OF CELLULOSE

Directory of Open Access Journals (Sweden)

SUMARI SUMARI

2014-05-01

Full Text Available The aim of this study is to optimize ultrasound treatment to produce fragment of cellulose that is low in particles size, crystallite size, and crystallinity. Slurry of 1 % (w/v the cellulose was sonicated at different time periods and temperatures. An ultrasonic reactor was operated at 300 Watts and 28 kHz to cut down the polymer into smaller particles. We proved that ultrasound damages and fragments the cellulose particles into shorter fibers. The fiber lengths were reduced from in the range of 80-120 µm to 30-50 µm due to an hour ultrasonication and became 20-30 µm after 5 hours. It was also found some signs of erosion on the surface and stringy. The acoustic cavitation also generated a decrease in particle size, crystallinity, and crystallite size of the cellulose along with increasing sonication time but it did not change d-spacing. However, the highest reduction of particle size, crystallite size, and crystallinity of the cellulose occurred within the first hour of ultrasonication, after which the efficiency was decreased. The particle diameter, crystallite size, and crystallinity were decreased from 19.88 µm to 15.96 µm, 5.81 Å to 2.98 Å, and 77.7% to 73.9% respectively due to an hour ultrasound treatment at 40 °C. The treatment that was conducted at 40 °C or 60 °C did not give a different effect significantly. Cellulose with a smaller particle and crystallite size as well as a more amorphous shape is preferred for further study.

A Simple Size Effect Model for Tension Perpendicular to the Grain

DEFF Research Database (Denmark)

Pedersen, M. U.; Clorius, Christian Odin; Damkilde, Lars

2003-01-01

The strength in tension perpendicular to the grain is known to decrease with an increase in the stressed volume. Usually this size effect is explained on a stochastic basis, that is, an explanation relying on the increased probability of encountering a strength reducing flaw when the volume...... of the material under stress is increased. This paper presents an experimental investigation on specimens with a well-defined structural orientation of the material. The experiments exhibit a large size effect and the nature of the failures encountered suggests that the size effect can be explained...... on a deterministic basis. Arguments for such a simple deterministic explanation of size effect is found in finite element modelling, using the orthotropic stiffness characteristics in the transverse plane of wood....

Global Hail Model

Science.gov (United States)

Werner, A.; Sanderson, M.; Hand, W.; Blyth, A.; Groenemeijer, P.; Kunz, M.; Puskeiler, M.; Saville, G.; Michel, G.

2012-04-01

Hail risk models are rare for the insurance industry. This is opposed to the fact that average annual hail losses can be large and hail dominates losses for many motor portfolios worldwide. Insufficient observational data, high spatio-temporal variability and data inhomogenity have hindered creation of credible models so far. In January 2012, a selected group of hail experts met at Willis in London in order to discuss ways to model hail risk at various scales. Discussions aimed at improving our understanding of hail occurrence and severity, and covered recent progress in the understanding of microphysical processes and climatological behaviour and hail vulnerability. The final outcome of the meeting was the formation of a global hail risk model initiative and the launch of a realistic global hail model in order to assess hail loss occurrence and severities for the globe. The following projects will be tackled: Microphysics of Hail and hail severity measures: Understand the physical drivers of hail and hailstone size development in different regions on the globe. Proposed factors include updraft and supercooled liquid water content in the troposphere. What are the thresholds drivers of hail formation around the globe? Hail Climatology: Consider ways to build a realistic global climatological set of hail events based on physical parameters including spatial variations in total availability of moisture, aerosols, among others, and using neural networks. Vulnerability, Exposure, and financial model: Use historical losses and event footprints available in the insurance market to approximate fragility distributions and damage potential for various hail sizes for property, motor, and agricultural business. Propagate uncertainty distributions and consider effects of policy conditions along with aggregating and disaggregating exposure and losses. This presentation provides an overview of ideas and tasks that lead towards a comprehensive global understanding of hail risk for

Atomic size effect on critical cooling rate and glass formation

International Nuclear Information System (INIS)

Jalali, Payman; Li Mo

2005-01-01

Atomic size effect on critical cooling rate and glass formability in a model binary system is investigated using molecular dynamics simulation. To isolate atomic size effect from the rest of the factors that critically influence the glass formation, a hard sphere model is employed in conjunction with a newly developed densification method. The glass formability is defined as a set of optimal conditions that result in the slowest cooling rate of the glass-forming liquid. Critical cooling rates are identified from extensive molecular dynamics simulations. A kinetic glass-forming diagram is mapped out that marks the boundary between the glass-forming regions and competing crystalline phases in terms of the parameters of the atomic size ratio and alloy concentration. It is found that the potency of the atomic size difference on glass formation is influenced greatly by the competing metastable and equilibrium crystalline phases in the system, and the kinetic processes leading to the formation of these phases. The mechanisms of the atomic size effect on topological instability of crystal packing and glass formation are discussed

Small and medium-sized firms top management teams’ decision making in global acquisitions

Directory of Open Access Journals (Sweden)

Timothy Kiessling

2009-07-01

Full Text Available The new global marketplace has caused changes in some organizations’/industries’ forms and execution of strategy and reliance on international personnel. Entry and success through the accumulation of knowledge in the global marketplace have become the impetus for sustainable competitive/developmental advantage for many corporations. Many organizations choose a strategy focusing on international acquisitions in foreign markets to compete effectively in the current ever-changing dynamic competitive landscape. After acquisition, the monitoring of the operations of the new international subsidiary by US firms typically is an ethnocentric example of applying home-country standards and controls. We suggest that the top management team (TMT of a firm is a valuable resource, needs to be retained and that ethnocentric monitoring must be reconsidered. This research focuses on the TMT and their value to the firm to help explain the variation in acquisition success. Thus post-acquisition integration and monitoring must account for this valuable asset.

Size effects in the mechanical behavior of cellular materials

NARCIS (Netherlands)

Tekoglu, C; Onck, PR

Effective mechanical properties of cellular materials depend strongly on the specimen size to the cell size ratio. Experimental studies performed on aluminium foams show that under uniaxial compression, the stiffness of these materials falls below the corresponding bulk value, when the ratio of the

Comprehensive effective and efficient global public health surveillance

Directory of Open Access Journals (Sweden)

McNabb Scott JN

2010-12-01

Full Text Available Abstract At a crossroads, global public health surveillance exists in a fragmented state. Slow to detect, register, confirm, and analyze cases of public health significance, provide feedback, and communicate timely and useful information to stakeholders, global surveillance is neither maximally effective nor optimally efficient. Stakeholders lack a globa surveillance consensus policy and strategy; officials face inadequate training and scarce resources. Three movements now set the stage for transformation of surveillance: 1 adoption by Member States of the World Health Organization (WHO of the revised International Health Regulations (IHR[2005]; 2 maturation of information sciences and the penetration of information technologies to distal parts of the globe; and 3 consensus that the security and public health communities have overlapping interests and a mutual benefit in supporting public health functions. For these to enhance surveillance competencies, eight prerequisites should be in place: politics, policies, priorities, perspectives, procedures, practices, preparation, and payers. To achieve comprehensive, global surveillance, disparities in technical, logistic, governance, and financial capacities must be addressed. Challenges to closing these gaps include the lack of trust and transparency; perceived benefit at various levels; global governance to address data power and control; and specified financial support from globa partners. We propose an end-state perspective for comprehensive, effective and efficient global, multiple-hazard public health surveillance and describe a way forward to achieve it. This end-state is universal, global access to interoperable public health information when it’s needed, where it’s needed. This vision mitigates the tension between two fundamental human rights: first, the right to privacy, confidentiality, and security of personal health information combined with the right of sovereign, national entities

Comprehensive effective and efficient global public health surveillance.

Science.gov (United States)

McNabb, Scott J N

2010-12-03

At a crossroads, global public health surveillance exists in a fragmented state. Slow to detect, register, confirm, and analyze cases of public health significance, provide feedback, and communicate timely and useful information to stakeholders, global surveillance is neither maximally effective nor optimally efficient. Stakeholders lack a globa surveillance consensus policy and strategy; officials face inadequate training and scarce resources.Three movements now set the stage for transformation of surveillance: 1) adoption by Member States of the World Health Organization (WHO) of the revised International Health Regulations (IHR[2005]); 2) maturation of information sciences and the penetration of information technologies to distal parts of the globe; and 3) consensus that the security and public health communities have overlapping interests and a mutual benefit in supporting public health functions. For these to enhance surveillance competencies, eight prerequisites should be in place: politics, policies, priorities, perspectives, procedures, practices, preparation, and payers.To achieve comprehensive, global surveillance, disparities in technical, logistic, governance, and financial capacities must be addressed. Challenges to closing these gaps include the lack of trust and transparency; perceived benefit at various levels; global governance to address data power and control; and specified financial support from globa partners.We propose an end-state perspective for comprehensive, effective and efficient global, multiple-hazard public health surveillance and describe a way forward to achieve it. This end-state is universal, global access to interoperable public health information when it's needed, where it's needed. This vision mitigates the tension between two fundamental human rights: first, the right to privacy, confidentiality, and security of personal health information combined with the right of sovereign, national entities to the ownership and stewardship

State Support: A Prerequisite for Global Health Network Effectiveness; Comment on “Four Challenges that Global Health Networks Face”

Directory of Open Access Journals (Sweden)

Robert Marten

2018-03-01

Full Text Available Shiffman recently summarized lessons for network effectiveness from an impressive collection of case-studies. However, in common with most global health governance analysis in recent years, Shiffman underplays the important role of states in these global networks. As the body which decides and signs international agreements, often provides the resourcing, and is responsible for implementing initiatives all contributing to the prioritization of certain issues over others, state recognition and support is a prerequisite to enabling and determining global health networks’ success. The role of states deserves greater attention, analysis and consideration. We reflect upon the underappreciated role of the state within the current discourse on global health. We present the tobacco case study to illustrate the decisive role of states in determining progress for global health networks, and highlight how states use a legitimacy loop to gain legitimacy from and provide legitimacy to global health networks. Moving forward in assessing global health networks’ effectiveness, further investigating state support as a determinant of success will be critical. Understanding how global health networks and states interact and evolve to shape and support their respective interests should be a focus for future research.

Effect-Size Measures and Meta-Analytic Thinking in Counseling Psychology Research

Science.gov (United States)

Henson, Robin K.

2006-01-01

Effect sizes are critical to result interpretation and synthesis across studies. Although statistical significance testing has historically dominated the determination of result importance, modern views emphasize the role of effect sizes and confidence intervals. This article accessibly discusses how to calculate and interpret the effect sizes…

Size Effect of the 2-D Bodies on the Geothermal Gradient and Q-A Plot

Science.gov (United States)

Thakur, M.; Blackwell, D. D.

2009-12-01

Using numerical models we have investigated some of the criticisms on the Q-A plot of related to the effect of size of the body on the slope and reduced heat flow. The effects of horizontal conduction depend on the relative difference of radioactivity between the body and the country rock (assuming constant thermal conductivity). Horizontal heat transfer due to different 2-D bodies was numerically studied in order to quantify resulting temperature differences at the Moho and errors on the predication of Qr (reduced heat flow). Using the two end member distributions of radioactivity, the step model (thickness 10km) and exponential model, different 2-D models of horizontal scale (width) ranging from 10 -500 km were investigated. Increasing the horizontal size of the body tends to move observations closer towards the 1-D solution. A temperature difference of 50 oC is produced (for the step model) at Moho between models of width 10 km versus 500 km. In other words the 1-D solution effectively provides large scale averaging in terms of heat flow and temperature field in the lithosphere. For bodies’ ≤ 100 km wide the geotherms at shallower levels are affected, but at depth they converge and are 50 oC lower than that of the infinite plate model temperature. In case of 2-D bodies surface heat flow is decreased due to horizontal transfer of heat, which will shift the Q-A point vertically downward on the Q-A plot. The smaller the size of the body, the more will be the deviation from the 1-D solution and the more will be the movement of Q-A point downwards on a Q-A plot. On the Q-A plot, a limited points of bodies of different sizes with different radioactivity contrast (for the step and exponential model), exactly reproduce the reduced heat flow Qr. Thus the size of the body can affect the slope on a Q-A plot but Qr is not changed. Therefore, Qr ~ 32 mWm-2 obtained from the global terrain average Q-A plot represents the best estimate of stable continental mantle heat

The effects of particle size distribution and induced unpinning during grain growth

International Nuclear Information System (INIS)

Thompson, G.S.; Rickman, J.M.; Harmer, M.P.; Holm, E.A.

1996-01-01

The effect of a second-phase particle size distribution on grain boundary pinning was studied using a Monte Carlo simulation technique. Simulations were run using a constant number density of both whisker and rhombohedral particles, and the effect of size distribution was studied by varying the standard deviation of the distribution around a constant mean particle size. The results of present simulations indicate that, in accordance with the stereological assumption of the topological pinning model, changes in distribution width had no effect on the pinned grain size. The effect of induced unpinning of particles on microstructure was also studied. In contrast to predictions of the topological pinning model, a power law dependence of pinned grain size on particle size was observed at T=0.0. Based on this, a systematic deviation to the stereological predictions of the topological pinning model is observed. The results of simulations at higher temperatures indicate an increasing power law dependence of pinned grain size on particle size, with the slopes of the power law dependencies fitting an Arrhenius relation. The effect of induced unpinning of particles was also studied in order to obtain a correlation between particle/boundary concentration and equilibrium grain size. The results of simulations containing a constant number density of monosized rhombohedral particles suggest a strong power law correlation between the two parameters. copyright 1996 Materials Research Society

Forecasting effects of global warming on biodiversity

DEFF Research Database (Denmark)

Botkin, D.B.; Saxe, H.; Araújo, M.B.

2007-01-01

The demand for accurate forecasting of the effects of global warming on biodiversity is growing, but current methods for forecasting have limitations. In this article, we compare and discuss the different uses of four forecasting methods: (1) models that consider species individually, (2) niche...... and theoretical ecological results suggest that many species could be at risk from global warming, during the recent ice ages surprisingly few species became extinct. The potential resolution of this conundrum gives insights into the requirements for more accurate and reliable forecasting. Our eight suggestions...

A Global Modeling Study on Carbonaceous Aerosol Microphysical Characteristics and Radiative Effects

Science.gov (United States)

Bauer, S. E.; Menon, S.; Koch, D.; Bond, T. C.; Tsigaridis, K.

2010-01-01

Recently, attention has been drawn towards black carbon aerosols as a short-term climate warming mitigation candidate. However the global and regional impacts of the direct, indirect and semi-direct aerosol effects are highly uncertain, due to the complex nature of aerosol evolution and the way that mixed, aged aerosols interact with clouds and radiation. A detailed aerosol microphysical scheme, MATRIX, embedded within the GISS climate model is used in this study to present a quantitative assessment of the impact of microphysical processes involving black carbon, such as emission size distributions and optical properties on aerosol cloud activation and radiative effects. Our best estimate for net direct and indirect aerosol radiative flux change between 1750 and 2000 is -0.56 W/m2. However, the direct and indirect aerosol effects are quite sensitive to the black and organic carbon size distribution and consequential mixing state. The net radiative flux change can vary between -0.32 to -0.75 W/m2 depending on these carbonaceous particle properties at emission. Taking into account internally mixed black carbon particles let us simulate correct aerosol absorption. Absorption of black carbon aerosols is amplified by sulfate and nitrate coatings and, even more strongly, by organic coatings. Black carbon mitigation scenarios generally showed reduced radiative fluxeswhen sources with a large proportion of black carbon, such as diesel, are reduced; however reducing sources with a larger organic carbon component as well, such as bio-fuels, does not necessarily lead to a reduction in positive radiative flux.

Effects of globalization on state budgeting system in Ukraine

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Bobukh S.О.

2017-06-01

Full Text Available When writing the scientific article the scientific approaches of scientists concerning the essence of budgeting have been described. The paper deals with the principles of budgeting on the basis of which three main methodological components are singled out. It also analyzes the budgeting goals. The author investigates the impact of globalization on the system of state budgeting in Ukraine, its positive and negative effects. Despite significant achievements it is necessary to explore the effects of globalization on the system of state budgeting in Ukraine. Budgeting is the management technology that provides the formation of budgets for the selected objects and their use to ensure optimal structure and correlation of profits and expenses, income and expenditure, assets and liabilities of the organization or its components to achieve the set goals taking into account the influence of the environment. It should be emphasized that budgeting in no way replaces the control system, but only creates a new approach to management from the standpoint of the balance of incomes and expenditures, profits and expenses, assets and liabilities of the organization as a whole or its components. The state budgeting of the country as the part of the financial system is the channel through which economic globalization, namely financial globalization, affects economic development of the state. Favorable global effect occurs, in particular, in terms of the impact on financial development. Therefore, it is necessary to + the nature of the relationship between these two processes.

The Effect of Family Size on Incentive Effects of Welfare Transfers in Two-Parent Families

Science.gov (United States)

Lewin, Alisa C.; Maurin, Eric

2005-01-01

Family size is an important determinant of family well-being, and it is a good predictor of poverty. This study examines effects of waiving the 100-hour rule, by family size, and distinguishes between the "work-incentive effects" and the "eligibility effects" of the waiver. The 100-hour rule limits eligibility to aid to…

[Geography of effective size of rural populations of Northern Eurasia. Geographic correlation between effective size and level of heterozygosity of populations].

Science.gov (United States)

Evsiukov, A N; Zhukova, O V; Sheremet'eva, V A; Shneĭder, Iu V; Rychkov, Iu G

1996-11-01

A significant geographical correlation (r = 0.719) was found between the logarithm of effective size (InNe) and heterozygosity level (H) in populations under the assumption of the Hardy-Weinberg equilibrium. The area of highest positive correlation was positioned meridionally between the Ob and Yenisei rivers, from the Arctic coast of Taimyr Peninsula to eastern Sayans and the southern Cis-Baikal region, i.e., in the same region where the highest distribution density of mean Ne values was found. Two additional areas of high correlations were found on the northern Black Sea coast and in the lower Lena river region. Analysis and mapping of correlation ratios eta H/lnNe2 and eta lnNe/H2 revealed that effective size substantially influenced heterozygosity level (as could be expected in the case of an intense gene drift), and heterozygosity level influenced effective size to the same extent. The latter relationship indicated an intense adaptation, and changes in diversity of the gene pool caused substantial demographic changes. However, this might be accounted for by direct gene migration into a population prevailing over reverse migration, i.e., mechanical population growth prevailing over natural growth.

Size and series effects on the economics of nuclear power plants

International Nuclear Information System (INIS)

Rouyer, J.L.; Marcetteau, P.; Nisan, S.

2001-01-01

This paper updates data and models concerning size and series effects on the economics of nuclear power plants. Size effect is the observation that, for a given technology, capital cost of a plant increases less rapidly than its capacity. The overall scaling exponent is derived from specific exponents for different plant items. It varies for industrial LWR and PHWR between 0.4 to 0.7. Series effect comprises two types of effects: a) fabrication in series of equipment, thus reducing unit cost with increased number of units; b) Increased efficiency through the feedback of experience obtained from the on-site realisation of a number of identical plants. Size and series effects are combined in the realisation of a full programme of a same standard model of nuclear power plants, for a given country or for several countries, in the same period of time (typically 10 years). Calculations have been performed to compare size and series effects for a 15000 MWe programme to be installed within 10 years, and reactor sizes varying from 600 MWe to 1500 MWe. The different options regarding the size of PWR standard model have also been compared on the basis of the least leveled electricity cost. The results of the calculations show that a standardised series of 1500 MWe appears presently the best solution in densely industrialized countries. In the long term, reactors of 1000 MWe, or less, (if new concepts sharply decrease unit cost per kW installed), may be preferred because of the associated large series effect. (authors)

What is Driving Global Imbalances? The Global Savings Glut Hypothesis Reexamined

Directory of Open Access Journals (Sweden)

Jai-Won Ryou

2009-12-01

Full Text Available In the middle of the global financial crisis, global imbalances seem to have been resolved to some extent, but it remains to be seen whether these imbalances will emerge again along with economic recovery. In order to cope with this global issue, we need to clarify what caused global imbalances in the first place. This paper aims to evaluate the relative importance of the "global savings glut" to the U.S. external imbalances. Drawing on the portfolio balance model, we analyze how the process of interaction between the U.S. current account deficit, capital inflows, and the U.S. dollar exchange rate is linked to domestic and external factors. Our empirical analysis shows that the U.S. current account deficit maintained since the early 1990s is mainly driven by the domestic factors, such as a decrease in the U.S. national savings and an increase in money supply growth. The size of the negative effect of a "global savings glut" measured by an increase in the East Asian countries' national savings (i.e. China, Japan and Korea on the U.S. current account seems to be exaggerated. Meanwhile, current account does not appear to be sensitive to changes in the exchange rate. This finding implies that the rectification of global imbalances is hardly possible to achieve by means of depreciating the U.S. dollar alone while leaving the structural factors unchanged. In order to achieve global rebalancing, the U.S. should increase its savings rate, reduce fiscal deficit, and tighten its money supply. While an increase in the domestic demand in the surplus countries such as China and Japan may be helpful in rectifying global imbalances, it appears to be insufficient per se.

Effects of LiDAR point density, sampling size and height threshold on estimation accuracy of crop biophysical parameters.

Science.gov (United States)

Luo, Shezhou; Chen, Jing M; Wang, Cheng; Xi, Xiaohuan; Zeng, Hongcheng; Peng, Dailiang; Li, Dong

2016-05-30

Vegetation leaf area index (LAI), height, and aboveground biomass are key biophysical parameters. Corn is an important and globally distributed crop, and reliable estimations of these parameters are essential for corn yield forecasting, health monitoring and ecosystem modeling. Light Detection and Ranging (LiDAR) is considered an effective technology for estimating vegetation biophysical parameters. However, the estimation accuracies of these parameters are affected by multiple factors. In this study, we first estimated corn LAI, height and biomass (R2 = 0.80, 0.874 and 0.838, respectively) using the original LiDAR data (7.32 points/m2), and the results showed that LiDAR data could accurately estimate these biophysical parameters. Second, comprehensive research was conducted on the effects of LiDAR point density, sampling size and height threshold on the estimation accuracy of LAI, height and biomass. Our findings indicated that LiDAR point density had an important effect on the estimation accuracy for vegetation biophysical parameters, however, high point density did not always produce highly accurate estimates, and reduced point density could deliver reasonable estimation results. Furthermore, the results showed that sampling size and height threshold were additional key factors that affect the estimation accuracy of biophysical parameters. Therefore, the optimal sampling size and the height threshold should be determined to improve the estimation accuracy of biophysical parameters. Our results also implied that a higher LiDAR point density, larger sampling size and height threshold were required to obtain accurate corn LAI estimation when compared with height and biomass estimations. In general, our results provide valuable guidance for LiDAR data acquisition and estimation of vegetation biophysical parameters using LiDAR data.

Effects of FK506 on Hippocampal CA1 Cells Following Transient Global Ischemia/Reperfusion in Wistar Rat

Directory of Open Access Journals (Sweden)

Zahra-Nadia Sharifi

2012-01-01

Full Text Available Transient global cerebral ischemia causes loss of pyramidal cells in CA1 region of hippocampus. In this study, we investigated the neurotrophic effect of the immunosuppressant agent FK506 in rat after global cerebral ischemia. Both common carotid arteries were occluded for 20 minutes followed by reperfusion. In experimental group 1, FK506 (6 mg/kg was given as a single dose exactly at the time of reperfusion. In the second group, FK506 was administered at the beginning of reperfusion, followed by its administration intraperitoneally (IP 6, 24, 48, and 72 hours after reperfusion. FK506 failed to show neurotrophic effects on CA1 region when applied as a single dose of 6 mg/kg. The cell number and size of the CA1 pyramidal cells were increased, also the number of cell death decreased in this region when FK506 was administrated 48 h after reperfusion. This work supports the possible use of FK506 in treatment of ischemic brain damage.

State Support: A Prerequisite for Global Health Network Effectiveness Comment on "Four Challenges that Global Health Networks Face".

Science.gov (United States)

Marten, Robert; Smith, Richard D

2017-07-24

Shiffman recently summarized lessons for network effectiveness from an impressive collection of case-studies. However, in common with most global health governance analysis in recent years, Shiffman underplays the important role of states in these global networks. As the body which decides and signs international agreements, often provides the resourcing, and is responsible for implementing initiatives all contributing to the prioritization of certain issues over others, state recognition and support is a prerequisite to enabling and determining global health networks' success. The role of states deserves greater attention, analysis and consideration. We reflect upon the underappreciated role of the state within the current discourse on global health. We present the tobacco case study to illustrate the decisive role of states in determining progress for global health networks, and highlight how states use a legitimacy loop to gain legitimacy from and provide legitimacy to global health networks. Moving forward in assessing global health networks' effectiveness, further investigating state support as a determinant of success will be critical. Understanding how global health networks and states interact and evolve to shape and support their respective interests should be a focus for future research. © 2018 The Author(s); Published by Kerman University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Size-Effects in Void Growth

DEFF Research Database (Denmark)

Niordson, Christian Frithiof

2005-01-01

The size-effect on ductile void growth in metals is investigated. The analysis is based on unit cell models both of arrays of cylindrical voids under plane strain deformation, as well as arrays of spherical voids using an axisymmetric model. A recent finite strain generalization of two higher order...... strain gradient plasticity models is implemented in a finite element program, which is used to study void growth numerically. The results based on the two models are compared. It is shown how gradient effects suppress void growth on the micron scale when compared to predictions based on conventional...... models. This increased resistance to void growth, due to gradient hardening, is accompanied by an increase in the overall strength for the material. Furthermore, for increasing initial void volume fraction, it is shown that the effect of gradients becomes more important to the overall response but less...

Will Outer Tropical Cyclone Size Change due to Anthropogenic Warming?

Science.gov (United States)

Schenkel, B. A.; Lin, N.; Chavas, D. R.; Vecchi, G. A.; Knutson, T. R.; Oppenheimer, M.

2017-12-01

Prior research has shown significant interbasin and intrabasin variability in outer tropical cyclone (TC) size. Moreover, outer TC size has even been shown to vary substantially over the lifetime of the majority of TCs. However, the factors responsible for both setting initial outer TC size and determining its evolution throughout the TC lifetime remain uncertain. Given these gaps in our physical understanding, there remains uncertainty in how outer TC size will change, if at all, due to anthropogenic warming. The present study seeks to quantify whether outer TC size will change significantly in response to anthropogenic warming using data from a high-resolution global climate model and a regional hurricane model. Similar to prior work, the outer TC size metric used in this study is the radius in which the azimuthal-mean surface azimuthal wind equals 8 m/s. The initial results from the high-resolution global climate model data suggest that the distribution of outer TC size shifts significantly towards larger values in each global TC basin during future climates, as revealed by 1) statistically significant increase of the median outer TC size by 5-10% (p<0.05) according to a 1,000-sample bootstrap resampling approach with replacement and 2) statistically significant differences between distributions of outer TC size from current and future climate simulations as shown using two-sample Kolmogorov Smirnov testing (p<<0.01). Additional analysis of the high-resolution global climate model data reveals that outer TC size does not uniformly increase within each basin in future climates, but rather shows substantial locational dependence. Future work will incorporate the regional mesoscale hurricane model data to help focus on identifying the source of the spatial variability in outer TC size increases within each basin during future climates and, more importantly, why outer TC size changes in response to anthropogenic warming.

Effect sizes and cut-off points: a meta-analytical review of burnout in latin American countries.

Science.gov (United States)

García-Arroyo, Jose; Osca Segovia, Amparo

2018-05-02

Burnout is a highly prevalent globalized health issue that causes significant physical and psychological health problems. In Latin America research on this topic has increased in recent years, however there are no studies comparing results across countries, nor normative reference cut-offs. The present meta-analysis examines the intensity of burnout (emotional exhaustion, cynicism and personal accomplishment) in 58 adult nonclinical samples from 8 countries (Argentina, Brazil, Chile, Colombia, Ecuador, Mexico, Peru and Venezuela). We found low intensity of burnout but there are significant differences between countries in emotional exhaustion explained by occupation and language. Social and human service professionals (police officers, social workers, public administration staff) are more exhausted than health professionals (physicians, nurses) or teachers. The samples with Portuguese language score higher in emotional exhaustion than Spanish, supporting the theory of cultural relativism. Demographics (sex, age) and study variables (sample size, instrument), were not found significant to predict burnout. The effect size and confidence intervals found are proposed as a useful baseline for research and medical diagnosis of burnout in Latin American countries.

Effect of meal size and body size on specific dynamic action and gastric processing in decapod crustaceans.

Science.gov (United States)

McGaw, Iain J; Curtis, Daniel L

2013-11-01

Meal size and animal size are important factors affecting the characteristics of the specific dynamic action (SDA) response across a variety of taxa. The effects of these two variables on the SDA of decapod crustaceans are based on just a couple of articles, and are not wholly consistent with the responses reported for other aquatic ectotherms. Therefore, the effects of meal size and animal size on the characteristics of SDA response were investigated in a variety of decapod crustaceans from different families. A 6 fold increase in meal size (0.5%-3% body mass) resulted a pronounced increase in the duration of increased oxygen consumption, resulting in an increase in the SDA of Callinectes sapidus, Cancer gracilis, Hemigrapsus nudus, Homarus americanus, Pugettia producta and Procambarus clarkii. Unlike many other aquatic ectotherms a substantial increase between meal sizes was required, with meal size close to their upper feeding limit (3% body mass), before changes were evident. In many organisms increases in both duration and scope contribute to the overall SDA, here changes in scope as a function of meal size were weak, suggesting that a similar amount of energy is required to upregulate gastric processes, regardless of meal size. The SDA characteristics were less likely to be influenced by the size of the animal, and there was no difference in the SDA (kJ) as a function of size in H. americanus or Cancer irroratus when analysed as mass specific values. In several fish species characteristics of the SDA response are more closely related to the transit times of food, rather than the size of a meal. To determine if a similar trend occurred in crustaceans, the transit rates of different sized meals were followed through the digestive system using a fluoroscope. Although there was a trend towards larger meals taking longer to pass through the gut, this was only statistically significant for P. clarkii. There were some changes in transit times as a function of animal

Economic Effects of Increased Control Zone Sizes in Conflict Resolution

Science.gov (United States)

Datta, Koushik

1998-01-01

A methodology for estimating the economic effects of different control zone sizes used in conflict resolutions between aircraft is presented in this paper. The methodology is based on estimating the difference in flight times of aircraft with and without the control zone, and converting the difference into a direct operating cost. Using this methodology the effects of increased lateral and vertical control zone sizes are evaluated.

Size, Shape and Impurity Effects on Superconducting critical temperature.

Science.gov (United States)

Umeda, Masaki; Kato, Masaru; Sato, Osamu

Bulk superconductors have their own critical temperatures Tc. However, for a nano-structured superconductor, Tc depends on size and shape of the superconductor. Nishizaki showed that the high pressure torsion on bulks of Nb makes Tc higher, because the torsion makes many nano-sized fine grains in the bulks. However the high pressure torsion on bulks of V makes Tc lower, and Nishizaki discussed that the decrease of Tc is caused by impurities in the bulks of V. We studied size, shape, and impurity effects on Tc, by solving the Gor'kov equations, using the finite element method. We found that smaller and narrower superconductors show higher Tc. We found how size and shape affects Tc by studying spacial order parameter distributions and quasi-particle eigen-energies. Also we studied the impurity effects on Tc, and found that Tc decreases with increase of scattering rate by impurities. This work was supported in part of KAKENHI Grant Number JP26400367 and JP16K05460, and program for leading graduate schools of ministry of education, culture, sports, science and technology-Japan.

Size Effect on Acoustic Emission Characteristics of Coal-Rock Damage Evolution

Directory of Open Access Journals (Sweden)

Zhijie Wen

2017-01-01

Full Text Available Coal-gas outburst, rock burst, and other mine dynamic disasters are closely related to the instability and failure of coal-rock. Coal-rock is the assemblies of mineral particles of varying sizes and shapes bonded together by cementing materials. The damage and rupture process of coal-rock is accompanied by acoustic emission (AE, which can be used as an effective means to monitor and predict the instability of coal-rock body. In this manuscript, considering the size effect of coal-rock, the influence of different height to diameter ratio on the acoustic emission characteristics of coal-rock damage evolution was discussed by microparticle flow PFC2D software platform. The results show that coal-rock size influences the uniaxial compressive strength, peak strain, and elastic modulus of itself; the size effect has little effect on the acoustic emission law of coal-rock damage and the effects of the size of coal-rock samples on acoustic emission characteristics are mainly reflected in three aspects: the triggering time of acoustic emission, the strain range of strong acoustic emission, and the intensity of acoustic emission; the damage evolution of coal-rock specimen can be divided into 4 stages: initial damage, stable development, accelerated development, and damage.

Transient hydrodynamic finite-size effects in simulations under periodic boundary conditions

Science.gov (United States)

Asta, Adelchi J.; Levesque, Maximilien; Vuilleumier, Rodolphe; Rotenberg, Benjamin

2017-06-01

We use lattice-Boltzmann and analytical calculations to investigate transient hydrodynamic finite-size effects induced by the use of periodic boundary conditions. These effects are inevitable in simulations at the molecular, mesoscopic, or continuum levels of description. We analyze the transient response to a local perturbation in the fluid and obtain the local velocity correlation function via linear response theory. This approach is validated by comparing the finite-size effects on the steady-state velocity with the known results for the diffusion coefficient. We next investigate the full time dependence of the local velocity autocorrelation function. We find at long times a crossover between the expected t-3 /2 hydrodynamic tail and an oscillatory exponential decay, and study the scaling with the system size of the crossover time, exponential rate and amplitude, and oscillation frequency. We interpret these results from the analytic solution of the compressible Navier-Stokes equation for the slowest modes, which are set by the system size. The present work not only provides a comprehensive analysis of hydrodynamic finite-size effects in bulk fluids, which arise regardless of the level of description and simulation algorithm, but also establishes the lattice-Boltzmann method as a suitable tool to investigate such effects in general.

Finite size effects in simulations of protein aggregation.

Directory of Open Access Journals (Sweden)

Amol Pawar

Full Text Available It is becoming increasingly clear that the soluble protofibrillar species that proceed amyloid fibril formation are associated with a range of neurodegenerative disorders such as Alzheimer's and Parkinson diseases. Computer simulations of the processes that lead to the formation of these oligomeric species are starting to make significant contributions to our understanding of the determinants of protein aggregation. We simulate different systems at constant concentration but with a different number of peptides and we study the how the finite number of proteins affects the underlying free energy of the system and therefore the relative stability of the species involved in the process. If not taken into account, this finite size effect can undermine the validity of theoretical predictions regarding the relative stability of the species involved and the rates of conversion from one to the other. We discuss the reasons that give rise to this finite size effect form both a probabilistic and energy fluctuations point of view and also how this problem can be dealt by a finite size scaling analysis.

A qualitative test for intrinsic size effect on ferroelectric phase transitions

OpenAIRE

Wang, Jin; Tagantsev, Alexander K.; Setter, Nava

2010-01-01

The size effect in ferroelectrics is treated as a competition between the geometrical symmetry of the ferroelectric sample and its crystalline symmetry. The manifestation of this competition is shown to be polarization rotation, which is driven by temperature and/or size variations, thus providing a qualitative indication of intrinsic finite size effect on ferroelectrics. The concept is demonstrated in a simple case of PbTiO3 nanowires having their axis parallel to [111]C direction, where the...

The P Value Problem in Otolaryngology: Shifting to Effect Sizes and Confidence Intervals.

Science.gov (United States)

Vila, Peter M; Townsend, Melanie Elizabeth; Bhatt, Neel K; Kao, W Katherine; Sinha, Parul; Neely, J Gail

2017-06-01

There is a lack of reporting effect sizes and confidence intervals in the current biomedical literature. The objective of this article is to present a discussion of the recent paradigm shift encouraging the use of reporting effect sizes and confidence intervals. Although P values help to inform us about whether an effect exists due to chance, effect sizes inform us about the magnitude of the effect (clinical significance), and confidence intervals inform us about the range of plausible estimates for the general population mean (precision). Reporting effect sizes and confidence intervals is a necessary addition to the biomedical literature, and these concepts are reviewed in this article.

Evaluation of the Company Size Effect on Latin American Stock Markets

Directory of Open Access Journals (Sweden)

Juan Benjamín Duarte Duarte

2013-11-01

Full Text Available This paper assesses the existence of the size effect on the most important stock markets in Latin America (Argentina, Brazil, Chile, Colombia, Mexico and Peru for the period between 2002 and 2012, using the cross-section contrast methodology of the size effect in the CAPM context. Results show that there is reversed effect in some of the Latin American markets.

Nonlinear Cross-Diffusion with Size Exclusion

KAUST Repository

Burger, Martin

2010-01-01

The aim of this paper is to investigate the mathematical properties of a continuum model for diffusion of multiple species incorporating size exclusion effects. The system for two species leads to nonlinear cross-diffusion terms with double degeneracy, which creates significant novel challenges in the analysis of the system. We prove global existence of weak solutions and well-posedness of strong solutions close to equilibrium. We further study some asymptotics of the model, and in particular we characterize the large-time behavior of solutions. 2010 © Society for Industrial and Applied Mathematics.

Effects of Global Warming on Vibrio Ecology.

Science.gov (United States)

Vezzulli, Luigi; Pezzati, Elisabetta; Brettar, Ingrid; Höfle, Manfred; Pruzzo, Carla

2015-06-01

Vibrio-related infections are increasing worldwide both in humans and aquatic animals. Rise in global sea surface temperature (SST), which is approximately 1 °C higher now than 140 years ago and is one of the primary physical impacts of global warming, has been linked to such increases. In this chapter, major known effects of increasing SST on the biology and ecology of vibrios are described. They include the effects on bacterial growth rate, both in the field and in laboratory, culturability, expression of pathogenicity traits, and interactions with aquatic organisms and abiotic surfaces. Special emphasis is given to the effect of ocean warming on Vibrio interactions with zooplankters, which represent one of the most important aquatic reservoirs for these bacteria. The reported findings highlight the biocomplexity of the interactions between vibrios and their natural environment in a climate change scenario, posing the need for interdisciplinary studies to properly understand the connection between ocean warming and persistence and spread of vibrios in sea waters and the epidemiology of the diseases they cause.

Globalization, democracy, and child health in developing countries.

Science.gov (United States)

Welander, Anna; Lyttkens, Carl Hampus; Nilsson, Therese

2015-07-01

Good health is crucial for human and economic development. In particular poor health in childhood is of utmost concern since it causes irreversible damage and has implications later in life. Recent research suggests globalization is a strong force affecting adult and child health outcomes. Yet, there is much unexplained variation with respect to the globalization effect on child health, in particular in low- and middle-income countries. One factor that could explain such variation across countries is the quality of democracy. Using panel data for 70 developing countries between 1970 and 2009 this paper disentangles the relationship between globalization, democracy, and child health. Specifically the paper examines how globalization and a country's democratic status and historical experience with democracy, respectively, affect infant mortality. In line with previous research, results suggest that globalization reduces infant mortality and that the level of democracy in a country generally improves child health outcomes. Additionally, democracy matters for the size of the globalization effect on child health. If for example Côte d'Ivoire had been a democracy in the 2000-2009 period, this effect would translate into 1200 fewer infant deaths in an average year compared to the situation without democracy. We also find that nutrition is the most important mediator in the relationship. To conclude, globalization and democracy together associate with better child health in developing countries. Copyright © 2015 Elsevier Ltd. All rights reserved.

Influence of the molecular structure on indentation size effect in polymers

International Nuclear Information System (INIS)

Han, Chung-Souk

2010-01-01

Size dependent deformation of polymers has been observed by various researchers in various experimental settings including micro beam bending, foams and indentation testing. Here in this article the indentation size effect in polymers is examined which manifests itself in increased hardness at decreasing indentation depths. Based on previously suggested rationale of size dependent deformation and depth dependent hardness model the depth dependent hardness of various polymers are analyzed. It is found that polymers containing aromatic rings in their molecular structure exhibit depth dependent hardness above the micron length scale. For polymers not containing aromatic rings polymers the indentation size effect starts at smaller indentation depths if they are present at all.

Effects of yoga on cancer-related fatigue and global side-effect burden in older cancer survivors.

Science.gov (United States)

Sprod, Lisa K; Fernandez, Isabel D; Janelsins, Michelle C; Peppone, Luke J; Atkins, James N; Giguere, Jeffrey; Block, Robert; Mustian, Karen M

2015-01-01

Sixty percent of cancer survivors are 65years of age or older. Cancer and its treatments lead to cancer-related fatigue and many other side effects, in turn, creating substantial global side-effect burden (total burden from all side effects) which, ultimately, compromises functional independence and quality of life. Various modes of exercise, such as yoga, reduce cancer-related fatigue and global side-effect burden in younger cancer survivors, but no studies have specifically examined the effects of yoga on older cancer survivors. The purpose of this study was to assess the effects of a 4-week yoga intervention (Yoga for Cancer Survivors: YOCAS©®) on overall cancer-related fatigue, and due to its multidimensional nature, the subdomains of cancer-related fatigue (general, physical, emotional, and mental) and global side-effect burden in older cancer survivors. We conducted a secondary analysis on data from a multicenter phase III randomized controlled clinical trial with 2 arms (standard care and standard care plus a 4-week YOCAS©® intervention). The sample for this secondary analysis was 97 older cancer survivors (≥60years of age), between 2months and 2years post-treatment, who participated in the original trial. Participants in the YOCAS©® intervention arm reported significantly lower cancer-related fatigue, physical fatigue, mental fatigue, and global side-effect burden than participants in the standard care arm following the 4-week intervention period (peffective standardized yoga intervention for reducing cancer-related fatigue, physical fatigue, mental fatigue, and global side-effect burden among older cancer survivors. Copyright © 2014 Elsevier Inc. All rights reserved.

Attributional processes in the learned helplessness paradigm: behavioral effects of global attributions.

Science.gov (United States)

Mikulincer, M

1986-12-01

Following the learned helplessness paradigm, I assessed in this study the effects of global and specific attributions for failure on the generalization of performance deficits in a dissimilar situation. Helplessness training consisted of experience with noncontingent failures on four cognitive discrimination problems attributed to either global or specific causes. Experiment 1 found that performance in a dissimilar situation was impaired following exposure to globally attributed failure. Experiment 2 examined the behavioral effects of the interaction between stable and global attributions of failure. Exposure to unsolvable problems resulted in reduced performance in a dissimilar situation only when failure was attributed to global and stable causes. Finally, Experiment 3 found that learned helplessness deficits were a product of the interaction of global and internal attribution. Performance deficits following unsolvable problems were recorded when failure was attributed to global and internal causes. Results were discussed in terms of the reformulated learned helplessness model.

Studying the effect of particle size and coating type on the blood kinetics of superparamagnetic iron oxide nanoparticles

Directory of Open Access Journals (Sweden)

Roohi F

2012-08-01

Full Text Available Farnoosh Roohi, Jessica Lohrke, Andreas Ide, Gunnar Schütz, Katrin DasslerMR and CT Contrast Media Research, Bayer Pharma AG, Berlin, GermanyPurpose: Magnetic resonance imaging (MRI, one of the most powerful imaging techniques available, usually requires the use of an on-demand designed contrast agent to fully exploit its potential. The blood kinetics of the contrast agent represent an important factor that needs to be considered depending on the objective of the medical examination. For particulate contrast agents, such as superparamagnetic iron oxide nanoparticles (SPIOs, the key parameters are particle size and characteristics of the coating material. In this study we analyzed the effect of these two properties independently and systematically on the magnetic behavior and blood half-life of SPIOs.Methods: Eleven different SPIOs were synthesized for this study. In the first set (a, seven carboxydextran (CDX-coated SPIOs of different sizes (19–86 nm were obtained by fractionating a broadly size-distributed CDX–SPIO. The second set (b contained three SPIOs of identical size (50 nm that were stabilized with different coating materials, polyacrylic acid (PAA, polyethylene glycol, and starch. Furthermore, small PAA–SPIOs (20 nm were synthesized to gain a global insight into the effects of particle size vs coating characteristics. Saturation magnetization and proton relaxivity were determined to represent the magnetic and imaging properties. The blood half-life was analyzed in rats using MRI, time-domain nuclear magnetic resonance, and inductively coupled plasma optical emission spectrometry.Results: By changing the particle size without modifying any other parameters, the relaxivity r2 increased with increasing mean particle diameter. However, the blood half-life was shorter for larger particles. The effect of the coating material on magnetic properties was less pronounced, but it had a strong influence on blood kinetics depending on the

Effect Size Measures for Mediation Models: Quantitative Strategies for Communicating Indirect Effects

Science.gov (United States)

Preacher, Kristopher J.; Kelley, Ken

2011-01-01

The statistical analysis of mediation effects has become an indispensable tool for helping scientists investigate processes thought to be causal. Yet, in spite of many recent advances in the estimation and testing of mediation effects, little attention has been given to methods for communicating effect size and the practical importance of those…

Big bees do a better job: intraspecific size variation influences pollination effectiveness

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Pat Willmer

2014-09-01

Full Text Available 1. Bumblebees (Bombus spp. are efficient pollinators of many flowering plants, yet the pollen deposition performance of individual bees has not been investigated. Worker bumblebees exhibit large intraspecific and intra-nest size variation, in contrast with other eusocial bees; and their size influences collection and deposition of pollen grains. 2. Laboratory studies with B. terrestris workers and Vinca minor flowers showed that pollination effectiveness PE, as measured from pollen grains deposited on stigmas in single visits (SVD, was significantly positively related to bee size; larger bees deposited more grains, while the smallest individuals, with proportionally shorter tongues, were unable to collect or deposit pollen in these flowers. Individuals did not increase their pollen deposition over time, so handling experience does not influence SVD in Vinca minor. 3. Field studies using Geranium sanguineum and Echium vulgare, and multiple visiting species, confirmed that individual size affects SVD. All bumblebee species showed positive SVD/size effects, though even the smallest individuals did deposit pollen. Apis with its limited size variation showed no such detectable effect when visiting Geranium flowers. Two abundant hoverfly species also showed size effects, particularly when feeding for nectar on Echium. 4. Mean size of foragers also varied diurnally, with larger individuals active earlier and later, so that pollination effectiveness varies through a day; flowers routinely pollinated by bees may best be served by early morning dehiscence and visits from larger individuals. 5. Thus, while there are well-documented species-level variations in pollination effectiveness, the fine-scale individual differences between foragers should also be taken into account when assessing the reproductive outputs of biotically-pollinated plants.

The Effect of Trade Openness and Income on the Size of a Government

Directory of Open Access Journals (Sweden)

Taner TURAN

2016-02-01

Full Text Available This paper examines the effect of trade openness and per capita GDP on the size of government for Turkey and South Korea by means of ARDL approach to co-integration. We use different proxies to measure the size of government because not all measures of government size are appropriate to be employed in the estimates. Among the three (four different measures of government size of Korea (Turkey, only one for each country has a co-integrating relationship with openness and per capita GDP. Long run coeffi cients suggest that per capita GDP has a positive and signifi cant effect on the government sizes for Turkey and Korea, implying the validity of the Wagner’s law. However, while openness has a negative effect on government size for Turkey, it has a positive effect for Korea. Our results clearly highlight the importance of choosing an appropriate proxy for government size to reach robust and consistent results.

Blade size and weight effects in shovel design.

Science.gov (United States)

Freivalds, A; Kim, Y J

1990-03-01

The shovel is a basic tool that has undergone only nominal systematic design changes. Although previous studies found shovel-weight and blade-size effects of shovelling, the exact trade-off between the two has not been quantified. Energy expenditure, heart rate, ratings of perceived exertion and shovelling performance were measured on five subjects using five shovels with varying blade sizes and weights to move sand. Energy expenditure, normalised to subject weight and load handled, varied quadratically with the blade-size/shovel-weight (B/W) ratio. Minimum energy cost was at B/W = 0.0676 m2/kg, which for an average subject and average load would require an acceptable 5.16 kcal/min of energy expenditure. Subjects, through the ratings of perceived exertion, also strongly preferred the lighter shovels without regard to blade size. Too large a blade or too heavy a shovel increased energy expenditure beyond acceptable levels, while too small a blade reduced efficiency of the shovelling.

Effect of pore-size distribution on the collapse behaviour of anthropogenic sandy soil deposits

Directory of Open Access Journals (Sweden)

Baille Wiebke

2016-01-01

Full Text Available In the former open-pit mines of the Lusatian region in Germany, several liquefaction events have occurred during the recent years in the anthropogenic deposits made of very loose sandy soils. These events are related to the rising ground water table after the stop of controlled ground water lowering. The very loose state is due to the formation of sand aggregates (pseudo-grains during the deposition process. The pseudo-grains enclose larger voids of dimension greater than the single sand grain. Wetting induced collapse of the pseudo-grains is presumed to be one of the possible mechanisms triggering liquefaction. In the present study, the effect of larger voids on the wetting induced deformation behaviour of sandy soils is experimentally investigated by laboratory box tests. The deformation field in the sample during wetting was measured using Digital Image Correlation (DIC technique. The results show that the observed deformations are affected by the pore size distribution, thus the amount of voids between the pseudo-grains (macro-void ratio and the voids inside the pseudo-grains (matrix void ratio. The global void ratio of a sandy soil is not sufficient as single state parameter, but the pore size distribution has to be taken into account, experimentally as well as in modelling.

Size Effect in Tension Perpendicular to Grain

DEFF Research Database (Denmark)

Astrup, Thomas; Clorius, Christian Odin; Hoffmeyer, Preben

2004-01-01

The strength of wood is reduced when the stressed volume is increased. The phenomenon is termed size effect and is often explained as being stochastic in the sense that the probability of weak locations occurring in the wood increases with increased volume. This paper presents a hypothesis where ...

Numerical Evaluation of Size Effect on the Stress-Strain Behaviour of Geotextile-Reinforced Sand

DEFF Research Database (Denmark)

Hosseinpour, I.; Mirmoradi, S.H.; Barari, Amin

2010-01-01

This paper studies the effect of sample size on the stress-strain behavior and strength characteristics of geotextile reinforced sand using the finite element numerical analysis. The effect of sample size was investigated by studying the effects of varying the number of geotextile layers, the con......This paper studies the effect of sample size on the stress-strain behavior and strength characteristics of geotextile reinforced sand using the finite element numerical analysis. The effect of sample size was investigated by studying the effects of varying the number of geotextile layers...... on the mechanical behavior of reinforced sand decreases with an increase in the sample size....

Specific cesium activity in freshwater fish and the size effect

International Nuclear Information System (INIS)

Kulikov, A.O.; Ryabov, I.N.; USSR Academy of Sciences, Moscow

1992-01-01

The specific Cs-137 activity of muscle tissues of silver carp (Hypophthalmichthys molitrix) from the cooling pond of the Chernobyl nuclear power plant caught in 1987 and 1988 increased almost linearly with fish weight ('size effect') in contrast to liver tissue, whose specific activity remained independent of weight. A kinetic model for uptake and excretion was developed to describe the size effect in muscle tissue by introducing a weight-dependent Cs biological half-time to fish. Similar size effects of specific Cs-137 activity were also found for other species of fish from cooling pond, but were primarily attributed to changes in feeding habits with increasing weight of fish rather than to metabolic changes in feeding habits with both of muscle and liver tissue increased with fish weight for those species in contrast to silver carp. (author). 12 refs.; 12 figs.; 1 tab

Does increasing the size of bi-weekly samples of records influence results when using the Global Trigger Tool? An observational study of retrospective record reviews of two different sample sizes.

Science.gov (United States)

Mevik, Kjersti; Griffin, Frances A; Hansen, Tonje E; Deilkås, Ellen T; Vonen, Barthold

2016-04-25

To investigate the impact of increasing sample of records reviewed bi-weekly with the Global Trigger Tool method to identify adverse events in hospitalised patients. Retrospective observational study. A Norwegian 524-bed general hospital trust. 1920 medical records selected from 1 January to 31 December 2010. Rate, type and severity of adverse events identified in two different samples sizes of records selected as 10 and 70 records, bi-weekly. In the large sample, 1.45 (95% CI 1.07 to 1.97) times more adverse events per 1000 patient days (39.3 adverse events/1000 patient days) were identified than in the small sample (27.2 adverse events/1000 patient days). Hospital-acquired infections were the most common category of adverse events in both the samples, and the distributions of the other categories of adverse events did not differ significantly between the samples. The distribution of severity level of adverse events did not differ between the samples. The findings suggest that while the distribution of categories and severity are not dependent on the sample size, the rate of adverse events is. Further studies are needed to conclude if the optimal sample size may need to be adjusted based on the hospital size in order to detect a more accurate rate of adverse events. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Effects of sample size on the second magnetization peak in ...

Indian Academy of Sciences (India)

8+ crystals are observed at low temperatures, above the temperature where the SMP totally disappears. In particular, the onset of the SMP shifts to lower fields as the sample size decreases - a result that could be interpreted as a size effect in ...

Nanometer size field effect transistors for terahertz detectors

International Nuclear Information System (INIS)

Knap, W; Rumyantsev, S; Coquillat, D; Dyakonova, N; Teppe, F; Vitiello, M S; Tredicucci, A; Blin, S; Shur, M; Nagatsuma, T

2013-01-01

Nanometer size field effect transistors can operate as efficient resonant or broadband terahertz detectors, mixers, phase shifters and frequency multipliers at frequencies far beyond their fundamental cut-off frequency. This work is an overview of some recent results concerning the application of nanometer scale field effect transistors for the detection of terahertz radiation. (paper)

Combined Effects of Ocean Warming and Acidification on Copepod Abundance, Body Size and Fatty Acid Content.

Science.gov (United States)

Garzke, Jessica; Hansen, Thomas; Ismar, Stefanie M H; Sommer, Ulrich

2016-01-01

Concerns about increasing atmospheric CO2 concentrations and global warming have initiated studies on the consequences of multiple-stressor interactions on marine organisms and ecosystems. We present a fully-crossed factorial mesocosm study and assess how warming and acidification affect the abundance, body size, and fatty acid composition of copepods as a measure of nutritional quality. The experimental set-up allowed us to determine whether the effects of warming and acidification act additively, synergistically, or antagonistically on the abundance, body size, and fatty acid content of copepods, a major group of lower level consumers in marine food webs. Copepodite (developmental stages 1-5) and nauplii abundance were antagonistically affected by warming and acidification. Higher temperature decreased copepodite and nauplii abundance, while acidification partially compensated for the temperature effect. The abundance of adult copepods was negatively affected by warming. The prosome length of copepods was significantly reduced by warming, and the interaction of warming and CO2 antagonistically affected prosome length. Fatty acid composition was also significantly affected by warming. The content of saturated fatty acids increased, and the ratios of the polyunsaturated essential fatty acids docosahexaenoic- (DHA) and arachidonic acid (ARA) to total fatty acid content increased with higher temperatures. Additionally, here was a significant additive interaction effect of both parameters on arachidonic acid. Our results indicate that in a future ocean scenario, acidification might partially counteract some observed effects of increased temperature on zooplankton, while adding to others. These may be results of a fertilizing effect on phytoplankton as a copepod food source. In summary, copepod populations will be more strongly affected by warming rather than by acidifying oceans, but ocean acidification effects can modify some temperature impacts.

Effect size and statistical power in the rodent fear conditioning literature - A systematic review.

Science.gov (United States)

Carneiro, Clarissa F D; Moulin, Thiago C; Macleod, Malcolm R; Amaral, Olavo B

2018-01-01

Proposals to increase research reproducibility frequently call for focusing on effect sizes instead of p values, as well as for increasing the statistical power of experiments. However, it is unclear to what extent these two concepts are indeed taken into account in basic biomedical science. To study this in a real-case scenario, we performed a systematic review of effect sizes and statistical power in studies on learning of rodent fear conditioning, a widely used behavioral task to evaluate memory. Our search criteria yielded 410 experiments comparing control and treated groups in 122 articles. Interventions had a mean effect size of 29.5%, and amnesia caused by memory-impairing interventions was nearly always partial. Mean statistical power to detect the average effect size observed in well-powered experiments with significant differences (37.2%) was 65%, and was lower among studies with non-significant results. Only one article reported a sample size calculation, and our estimated sample size to achieve 80% power considering typical effect sizes and variances (15 animals per group) was reached in only 12.2% of experiments. Actual effect sizes correlated with effect size inferences made by readers on the basis of textual descriptions of results only when findings were non-significant, and neither effect size nor power correlated with study quality indicators, number of citations or impact factor of the publishing journal. In summary, effect sizes and statistical power have a wide distribution in the rodent fear conditioning literature, but do not seem to have a large influence on how results are described or cited. Failure to take these concepts into consideration might limit attempts to improve reproducibility in this field of science.

Finite size effects and chiral symmetry breaking in quenched three-dimensional QED

International Nuclear Information System (INIS)

Hands, S.; Kogut, J.B.

1990-01-01

Finite size effects and the chiral condensate are studied in three-dimensional QED by the Lanczos and the conjugate-gradient algorithms. Very substantial finite size effects are observed, but studies on L 3 lattices with L ranging from 8 to 80 indicate the development of a non-vanishing chiral condensate in the continuum limit of the theory. The systematics of the finite size effects and the fermion mass dependence in the conjugate-gradient algorithm are clarified in this extensive study. (orig.)

Exploring the role of movement in determining the global distribution of marine biomass using a coupled hydrodynamic - Size-based ecosystem model

Science.gov (United States)

Watson, James R.; Stock, Charles A.; Sarmiento, Jorge L.

2015-11-01

Modeling the dynamics of marine populations at a global scale - from phytoplankton to fish - is necessary if we are to quantify how climate change and other broad-scale anthropogenic actions affect the supply of marine-based food. Here, we estimate the abundance and distribution of fish biomass using a simple size-based food web model coupled to simulations of global ocean physics and biogeochemistry. We focus on the spatial distribution of biomass, identifying highly productive regions - shelf seas, western boundary currents and major upwelling zones. In the absence of fishing, we estimate the total ocean fish biomass to be ∼ 2.84 ×109 tonnes, similar to previous estimates. However, this value is sensitive to the choice of parameters, and further, allowing fish to move had a profound impact on the spatial distribution of fish biomass and the structure of marine communities. In particular, when movement is implemented the viable range of large predators is greatly increased, and stunted biomass spectra characterizing large ocean regions in simulations without movement, are replaced with expanded spectra that include large predators. These results highlight the importance of considering movement in global-scale ecological models.

Smart moves: effects of relative brain size on establishment success of invasive amphibians and reptiles.

Science.gov (United States)

Amiel, Joshua J; Tingley, Reid; Shine, Richard

2011-04-06

Brain size relative to body size varies considerably among animals, but the ecological consequences of that variation remain poorly understood. Plausibly, larger brains confer increased behavioural flexibility, and an ability to respond to novel challenges. In keeping with that hypothesis, successful invasive species of birds and mammals that flourish after translocation to a new area tend to have larger brains than do unsuccessful invaders. We found the same pattern in ectothermic terrestrial vertebrates. Brain size relative to body size was larger in species of amphibians and reptiles reported to be successful invaders, compared to species that failed to thrive after translocation to new sites. This pattern was found in six of seven global biogeographic realms; the exception (where relatively larger brains did not facilitate invasion success) was Australasia. Establishment success was also higher in amphibian and reptile families with larger relative brain sizes. Future work could usefully explore whether invasion success is differentially associated with enlargement of specific parts of the brain (as predicted by the functional role of the forebrain in promoting behavioural flexibility), or with a general size increase (suggesting that invasion success is facilitated by enhanced perceptual and motor skills, as well as cognitive ability).

Long-Term Effects of School Size on Students' Outcomes

DEFF Research Database (Denmark)

Humlum, Maria Knoth; Smith, Nina

We estimate the effect of school size on students' long-term outcomes such as high school completion, being out of the labor market, and earnings at the age of 30. We use rich register data on the entire population of Danish children attending grade 9 in the period 1986-2004. This allows us...... school size and alternative measures of long-term success in the educational system and the labor market. The positive impact of school size seems mainly to be driven by boys, students from families with a low educational level and students attending schools in urban areas....

How Will Global Environmental Changes Affect the Growth of Alien Plants?

Directory of Open Access Journals (Sweden)

Jujie Jia

2016-11-01

Full Text Available Global environmental changes can create novel habitats, promoting the growth of alien plants that often exhibit broad environmental tolerance and high phenotypic plasticity. However, the mechanisms underlying these growth promotory effects are unknown at present. Here, we conducted a phylogenetically controlled meta-analysis using data from 111 published studies encompassing the responses of 129 alien plants to global warming, increased precipitation, N deposition, and CO2 enrichment. We compared the differences in the responses of alien plants to the four global environmental change factors across six categories of functional traits between woody and non-woody life forms as well as C3 and C4 photosynthetic pathways. Our results showed that all four global change factors promote alien plant growth. Warming had a more positive effect on C4 than C3 plants. Although the effects of the four factors on the functional traits of alien plants were variable, plant growth was mainly promoted via an increase in growth rate and size. Our data suggest that potential future global environmental changes could further facilitate alien plant growth.

X-ray tube focal spot sizes: comprehensive studies of their measurement and effect of measured size in angiography

International Nuclear Information System (INIS)

Doi, K.; Loo, L.N.; Chan, H.P.

1982-01-01

Thirty-two focal spot sizes of four x-ray tubes were measured by the pinhole, star pattern, slit, and root-mean-square (RMS) methods under various exposure conditions. The modulation transfer functions (MTFs) and line spread functions (LSFs) were also determined. The star pattern focal spot sizes agreed with the effective sizes calculated from the frequencies at the first minimum of the MTF within 0.04 mm for large focal spots and within 0.01 mm for small focal spots. The focal spot size determined by the slit method was approximately equal to the width of the LSF at the cutoff level of 0.15 +/- 0.06 of the peak value. The RMS method provided the best correlation between the measured focal spot sizes and the corresponding image distributions of blood vessels. The pinhole and slit methods tended to overestimate the focal spot size, but the star pattern method tended to underestimate it. For approximately 90% of the focal spots, the average of the star and slit (or pinhole) focal spot sizes agreed with the RMS focal spot size within +/- 0.1 mm

Large-scale ocean connectivity and planktonic body size

KAUST Repository

Villarino, Ernesto; Watson, James R.; Jö nsson, Bror; Gasol, Josep M.; Salazar, Guillem; Acinas, Silvia G.; Estrada, Marta; Massana, Ramó n; Logares, Ramiro; Giner, Caterina R.; Pernice, Massimo C.; Olivar, M. Pilar; Citores, Leire; Corell, Jon; Rodrí guez-Ezpeleta, Naiara; Acuñ a, José Luis; Molina-Ramí rez, Axayacatl; Gonzá lez-Gordillo, J. Ignacio; Có zar, André s; Martí , Elisa; Cuesta, José A.; Agusti, Susana; Fraile-Nuez, Eugenio; Duarte, Carlos M.; Irigoien, Xabier; Chust, Guillem

2018-01-01

Global patterns of planktonic diversity are mainly determined by the dispersal of propagules with ocean currents. However, the role that abundance and body size play in determining spatial patterns of diversity remains unclear. Here we analyse spatial community structure - β-diversity - for several planktonic and nektonic organisms from prokaryotes to small mesopelagic fishes collected during the Malaspina 2010 Expedition. β-diversity was compared to surface ocean transit times derived from a global circulation model, revealing a significant negative relationship that is stronger than environmental differences. Estimated dispersal scales for different groups show a negative correlation with body size, where less abundant large-bodied communities have significantly shorter dispersal scales and larger species spatial turnover rates than more abundant small-bodied plankton. Our results confirm that the dispersal scale of planktonic and micro-nektonic organisms is determined by local abundance, which scales with body size, ultimately setting global spatial patterns of diversity.

Large-scale ocean connectivity and planktonic body size

KAUST Repository

Villarino, Ernesto

2018-01-04

Global patterns of planktonic diversity are mainly determined by the dispersal of propagules with ocean currents. However, the role that abundance and body size play in determining spatial patterns of diversity remains unclear. Here we analyse spatial community structure - β-diversity - for several planktonic and nektonic organisms from prokaryotes to small mesopelagic fishes collected during the Malaspina 2010 Expedition. β-diversity was compared to surface ocean transit times derived from a global circulation model, revealing a significant negative relationship that is stronger than environmental differences. Estimated dispersal scales for different groups show a negative correlation with body size, where less abundant large-bodied communities have significantly shorter dispersal scales and larger species spatial turnover rates than more abundant small-bodied plankton. Our results confirm that the dispersal scale of planktonic and micro-nektonic organisms is determined by local abundance, which scales with body size, ultimately setting global spatial patterns of diversity.

Comparison of visual scoring and quantitative planimetry methods for estimation of global infarct size on delayed enhanced cardiac MRI and validation with myocardial enzymes

Energy Technology Data Exchange (ETDEWEB)

Mewton, Nathan, E-mail: nmewton@gmail.com [Hopital Cardiovasculaire Louis Pradel, 28, Avenue Doyen Lepine, 69677 Bron cedex, Hospices Civils de Lyon (France); CREATIS-LRMN (Centre de Recherche et d' Applications en Traitement de l' Image et du Signal), Universite Claude Bernard Lyon 1, UMR CNRS 5220, U 630 INSERM (France); Revel, Didier [Hopital Cardiovasculaire Louis Pradel, 28, Avenue Doyen Lepine, 69677 Bron cedex, Hospices Civils de Lyon (France); CREATIS-LRMN (Centre de Recherche et d' Applications en Traitement de l' Image et du Signal), Universite Claude Bernard Lyon 1, UMR CNRS 5220, U 630 INSERM (France); Bonnefoy, Eric [Hopital Cardiovasculaire Louis Pradel, 28, Avenue Doyen Lepine, 69677 Bron cedex, Hospices Civils de Lyon (France); Ovize, Michel [Hopital Cardiovasculaire Louis Pradel, 28, Avenue Doyen Lepine, 69677 Bron cedex, Hospices Civils de Lyon (France); INSERM Unite 886 (France); Croisille, Pierre [Hopital Cardiovasculaire Louis Pradel, 28, Avenue Doyen Lepine, 69677 Bron cedex, Hospices Civils de Lyon (France); CREATIS-LRMN (Centre de Recherche et d' Applications en Traitement de l' Image et du Signal), Universite Claude Bernard Lyon 1, UMR CNRS 5220, U 630 INSERM (France)

2011-04-15

Purpose: Although delayed enhanced CMR has become a reference method for infarct size quantification, there is no ideal method to quantify total infarct size in a routine clinical practice. In a prospective study we compared the performance and post-processing time of a global visual scoring method to standard quantitative planimetry and we compared both methods to the peak values of myocardial biomarkers. Materials and methods: This study had local ethics committee approval; all patients gave written informed consent. One hundred and three patients admitted with reperfused AMI to our intensive care unit had a complete CMR study with gadolinium-contrast injection 4 {+-} 2 days after admission. A global visual score was defined on a 17-segment model and compared with the quantitative planimetric evaluation of hyperenhancement. The peak values of serum Troponin I (TnI) and creatine kinase (CK) release were measured in each patient. Results: The mean percentage of total left ventricular myocardium with hyperenhancement determined by the quantitative planimetry method was (20.1 {+-} 14.6) with a range of 1-68%. There was an excellent correlation between quantitative planimetry and visual global scoring for the hyperenhancement extent's measurement (r = 0.94; y = 1.093x + 0.87; SEE = 1.2; P < 0.001) The Bland-Altman plot showed a good concordance between the two approaches (mean of the differences = 1.9% with a standard deviation of 4.7). Mean post-processing time for quantitative planimetry was significantly longer than visual scoring post-processing time (23.7 {+-} 5.7 min vs 5.0 {+-} 1.1 min respectively, P < 0.001). Correlation between peak CK and quantitative planimetry was r = 0.82 (P < 0.001) and r = 0.83 (P < 0.001) with visual global scoring. Correlation between peak Troponin I and quantitative planimetry was r = 0.86 (P < 0.001) and r = 0.85 (P < 0.001) with visual global scoring. Conclusion: A visual approach based on a 17-segment model allows a rapid

Comparison of visual scoring and quantitative planimetry methods for estimation of global infarct size on delayed enhanced cardiac MRI and validation with myocardial enzymes

International Nuclear Information System (INIS)

Mewton, Nathan; Revel, Didier; Bonnefoy, Eric; Ovize, Michel; Croisille, Pierre

2011-01-01

Purpose: Although delayed enhanced CMR has become a reference method for infarct size quantification, there is no ideal method to quantify total infarct size in a routine clinical practice. In a prospective study we compared the performance and post-processing time of a global visual scoring method to standard quantitative planimetry and we compared both methods to the peak values of myocardial biomarkers. Materials and methods: This study had local ethics committee approval; all patients gave written informed consent. One hundred and three patients admitted with reperfused AMI to our intensive care unit had a complete CMR study with gadolinium-contrast injection 4 ± 2 days after admission. A global visual score was defined on a 17-segment model and compared with the quantitative planimetric evaluation of hyperenhancement. The peak values of serum Troponin I (TnI) and creatine kinase (CK) release were measured in each patient. Results: The mean percentage of total left ventricular myocardium with hyperenhancement determined by the quantitative planimetry method was (20.1 ± 14.6) with a range of 1-68%. There was an excellent correlation between quantitative planimetry and visual global scoring for the hyperenhancement extent's measurement (r = 0.94; y = 1.093x + 0.87; SEE = 1.2; P < 0.001) The Bland-Altman plot showed a good concordance between the two approaches (mean of the differences = 1.9% with a standard deviation of 4.7). Mean post-processing time for quantitative planimetry was significantly longer than visual scoring post-processing time (23.7 ± 5.7 min vs 5.0 ± 1.1 min respectively, P < 0.001). Correlation between peak CK and quantitative planimetry was r = 0.82 (P < 0.001) and r = 0.83 (P < 0.001) with visual global scoring. Correlation between peak Troponin I and quantitative planimetry was r = 0.86 (P < 0.001) and r = 0.85 (P < 0.001) with visual global scoring. Conclusion: A visual approach based on a 17-segment model allows a rapid and accurate

Effect of coal stress on grain size of the gotten

Energy Technology Data Exchange (ETDEWEB)

Sikora, W; Tront, A

1988-09-01

Presents investigation results on the effect of seam stress and strain state on winning as measured by the grain size of the gotten. The investigations were carried out at the Institute of Mining Mechanization of the Silesian Politechnical where the relations between parameters of seams and cutters and their effect on coal grain size and energy consumption have been studied for several years. The effect was examined on coal samples taken from 4 mines in the Upper Silesian coal basin using a model of the system: seam - cutter. Cubic samples (400x400x400 mm) were tested on the CMG KOMAG test stand equipped with the POS-1 cutting apparatus. Two types of coal were distinguished: that particularly sensitive to increased pressure on seam and that only negligibly susceptible. Corresponding graphs of coal grain size versus vertical pressure are shown. A function has been developed that characterizes this sensitivity depending on a material parameter that can be determined by workability tests. The relationship between coal strength and grain size yield greater than 10 mm in the gotten depending on dynamic crushability of coal is shown in graphs. 6 refs.

The effects of meal size, body size and temperature on gastric evacuation in pikeperch

DEFF Research Database (Denmark)

Koed, Anders

2001-01-01

Prey size had no effect on the gastric evacuation rate of pikeperch Stizostedion lucioperca. The gastric evacuation was adequately described applying an exponent of 0.5 in the power model. Applying length instead of weight of pikeperch in the gastric evacuation model resulted in a change of estim...

Indirect Effects of Global Change: From Physiological and Behavioral Mechanisms to Ecological Consequences.

Science.gov (United States)

Gunderson, Alex R; Tsukimura, Brian; Stillman, Jonathon H

2017-07-01

A major focus of current ecological research is to understand how global change makes species vulnerable to extirpation. To date, mechanistic ecophysiological analyses of global change vulnerability have focused primarily on the direct effects of changing abiotic conditions on whole-organism physiological traits, such as metabolic rate, locomotor performance, cardiac function, and critical thermal limits. However, species do not live in isolation within their physical environments, and direct effects of climate change are likely to be compounded by indirect effects that result from altered interactions with other species, such as competitors and predators. The Society for Integrative and Comparative Biology 2017 Symposium "Indirect Effects of Global Change: From Physiological and Behavioral Mechanisms to Ecological Consequences" was designed to synthesize multiple approaches to investigating the indirect effects of global change by bringing together researchers that study the indirect effects of global change from multiple perspectives across habitat, type of anthropogenic change, and level of biological organization. Our goal in bringing together researchers from different backgrounds was to foster cross-disciplinary insights into the mechanistic bases and higher-order ecological consequences of indirect effects of global change, and to promote collaboration among fields. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Pengaruh krisis keuangan global dan karakteristik perusahaan terhadap cash holding perusahaan di Indonesia

Directory of Open Access Journals (Sweden)

Bambang Sutrisno

2016-12-01

Full Text Available The aim of this study is to examine the effect of the global financial crisis and firm characteristics on corporate cash holdings in Indonesia. A total of 101 manufacturing firms listed in the Indonesia Stock Exchange from 2005 to 2014 are examined. This study employs panel regression with fixed effect model. The results show that Indonesia firms hold more cash during the global financial crisis than in the normal times. Investment opportunities set and divident payment have positive effect on cash holding, meanwhile firm size, capital expenditure, liquid assets substitutes, and leverage have negative effect on cash holding. 

The arithmetic problem size effect in children: an event-related potential study

Directory of Open Access Journals (Sweden)

Leen eVan Beek

2014-09-01

Full Text Available This study used for the first time event-related potentials (ERPs to examine the well-known arithmetic problem size effect in children. The electrophysiological correlates of this problem size effect have been well documented in adults, but such information in children is lacking. In the present study, 22 typically developing 12-year-olds were asked to solve single-digit addition problems of small (sum ≤ 10 and large problem size (sum > 10 and to speak the solution into a voice key while ERPs were recorded. Children displayed similar early and late components compared to previous adult studies on the problem size effect. There was no effect of problem size on the early components P1, N1 and P2. The peak amplitude of the N2 component showed more negative potentials on left and right anterior electrodes for large additions compared to small additions, which might reflect differences in attentional and working memory resources between large and small problems. The mean amplitude of the late positivity component (LPC, which follows the N2, was significantly larger for large than for small additions at right parieto-occipital electrodes, in line with previous adult data. The ERPs of the problem size effect during arithmetic might be a useful neural marker for future studies on fact retrieval impairments in children with mathematical difficulties.

GLOBALIZATION AND SMALL BUSINESSES AND ECONOMIES – CHALLENGES AND OPPORTUNITIES

Directory of Open Access Journals (Sweden)

NINKO KOSTOVSKI

2016-08-01

Full Text Available In this paper, we analyze the effect of globalization in general and from the viewpoint of the small and medium sized companies in the Republic of Macedonia, as a typical developing economy. Our survey of 100 managers and business owners from small and medium sized enterprises indicates that they tend to perceive the globalization with more conservative glasses as negative, or at the best, as a neutral phenomenon to their overall business prospects. However, to harvest the apparent opportunities of the globalization and to achieve the desired internationalization of their businesses, they call for intensive regional cooperation seeing it as a gateway to much harsher realms of the globalized market. The literature review and the examples from some other countries support these conservative standing of our managers and offer practical explanations why the approach towards the globalization is conservative and often even negative. Small business is important provider of new jobs, ideas and business concepts. However, with the opening of the global market it is a constant pursue for customers all around the world, having to meet their diverse and rapidly changing needs and facing extremely shortened delivery terms and product lifecycles. Many small companies, particularly from the developing countries are not adequately prepared to face the reality of this challenge. On the other hand, the big multinational companies receive more than hefty incentives to invest into the developing countries and that creates additional negative sentiments towards the globalization among the local companies.

Maternal effects and the evolution of brain size in birds: overlooked developmental constraints.

Science.gov (United States)

Garamszegi, L Z; Biard, C; Eens, M; Møller, A P; Saino, N; Surai, P

2007-01-01

A central dogma for the evolution of brain size posits that the maintenance of large brains incurs developmental costs, because they need prolonged periods to grow during the early ontogeny. Such constraints are supported by the interspecific relationship between ontological differences and relative brain size in birds and mammals. Given that mothers can strongly influence the development of the offspring via maternal effects that potentially involve substances essential for growing brains, we argue that such effects may represent an important but overlooked component of developmental constraints on brain size. To demonstrate the importance of maternal effect on the evolution of brains, we investigated the interspecific relationship between relative brain size and maternal effects, as reflected by yolk testosterone, carotenoids, and vitamins A and E in a phylogenetic study of birds. Females of species with relatively large brains invested more in eggs in terms of testosterone and vitamin E than females of species with small brains. The effects of carotenoid and vitamin A levels on the evolution of relative brain size were weaker and non-significant. The association between relative brain size and yolk testosterone was curvilinear, suggesting that very high testosterone levels can be suppressive. However, at least in moderate physiological ranges, the positive relationship between components of maternal effects and relative brain size may imply one aspect of developmental costs of large brains. The relationship between vitamin E and relative brain size was weakened when we controlled for developmental mode, and thus the effect of this antioxidant may be indirect. Testosterone-enhanced neurogenesis and vitamin E-mediated defence against oxidative stress may have key functions when the brain of the embryo develops, with evolutionary consequences for relative brain size.

Does length or neighborhood size cause the word length effect?

Science.gov (United States)

Jalbert, Annie; Neath, Ian; Surprenant, Aimée M

2011-10-01

Jalbert, Neath, Bireta, and Surprenant (2011) suggested that past demonstrations of the word length effect, the finding that words with fewer syllables are recalled better than words with more syllables, included a confound: The short words had more orthographic neighbors than the long words. The experiments reported here test two predictions that would follow if neighborhood size is a more important factor than word length. In Experiment 1, we found that concurrent articulation removed the effect of neighborhood size, just as it removes the effect of word length. Experiment 2 demonstrated that this pattern is also found with nonwords. For Experiment 3, we factorially manipulated length and neighborhood size, and found only effects of the latter. These results are problematic for any theory of memory that includes decay offset by rehearsal, but they are consistent with accounts that include a redintegrative stage that is susceptible to disruption by noise. The results also confirm the importance of lexical and linguistic factors on memory tasks thought to tap short-term memory.

Development and psychometric evaluation of a clinical global impression for schizoaffective disorder scale.

Science.gov (United States)

Allen, Michael H; Daniel, David G; Revicki, Dennis A; Canuso, Carla M; Turkoz, Ibrahim; Fu, Dong-Jing; Alphs, Larry; Ishak, K Jack; Bartko, John J; Lindenmayer, Jean-Pierre

2012-01-01

The Clinical Global Impression for Schizoaffective Disorder scale is a new rating scale adapted from the Clinical Global Impression scale for use in patients with schizoaffective disorder. The psychometric characteristics of the Clinical Global Impression for Schizoaffective Disorder are described. Content validity was assessed using an investigator questionnaire. Inter-rater reliability was determined with 12 sets of videotaped interviews rated independently by two trained individuals. Test-retest reliability was assessed using 30 randomly selected raters from clinical trials who evaluated the same videos on separate occasions two weeks apart. Convergent and divergent validity and effect size were evaluated by comparing scores between the Clinical Global Impression for Schizoaffective Disorder and the Positive and Negative Syndrome Scale, 21-item Hamilton Rating Scale for Depression, and Young Mania Rating Scale scales using pooled patient data from two clinical trials. Clinical Global Impression for Schizoaffective Disorder scores were then linked to corresponding Positive and Negative Syndrome Scale scores. Content validity was strong. Inter-rater agreement was good to excellent for most scales and subscales (intra-class correlation coefficient ≥ 0.50). Test-retest showed good reproducibility, with intraclass correlation coefficients ranging from 0.444 to 0.898. Spearman correlations between Clinical Global Impression for Schizoaffective Disorder domains and corresponding symptom scales were 0.60 or greater, and effect sizes for Clinical Global Impression for Schizoaffective Disorder overall and domain scores were similar to Positive and Negative Syndrome Scale Young Mania Rating Scale, and 21-item Hamilton Rating Scale for Depression scores. Raters anticipated that the scale might be less effective in distinguishing negative from depressive symptoms, and, in fact, the results here may reflect that clinical reality. Multiple lines of evidence support the

A review of finite size effects in quasi-zero dimensional superconductors.

Science.gov (United States)

Bose, Sangita; Ayyub, Pushan

2014-11-01

Quantum confinement and surface effects (SEs) dramatically modify most solid state phenomena as one approaches the nanometer scale, and superconductivity is no exception. Though we may expect significant modifications from bulk superconducting properties when the system dimensions become smaller than the characteristic length scales for bulk superconductors-such as the coherence length or the penetration depth-it is now established that there is a third length scale which ultimately determines the critical size at which Cooper pairing is destroyed. In quasi-zero-dimensional (0D) superconductors (e.g. nanocrystalline materials, isolated or embedded nanoparticles), one may define a critical particle diameter below which the mean energy level spacing arising from quantum confinement becomes equal to the bulk superconducting energy gap. The so-called Anderson criterion provides a remarkably accurate estimate of the limiting size for the destabilization of superconductivity in nanosystems. This review of size effects in quasi-0D superconductors is organized as follows. A general summary of size effects in nanostructured superconductors (section 1) is followed by a brief overview of their synthesis (section 2) and characterization using a variety of techniques (section 3). Section 4 reviews the size-evolution of important superconducting parameters-the transition temperature, critical fields and critical current-as the Anderson limit is approached from above. We then discuss the effect of thermodynamic fluctuations (section 5), which become significant in confined systems. Improvements in fabrication methods and the increasing feasibility of addressing individual nanoparticles using scanning probe techniques have lately opened up new directions in the study of nanoscale superconductivity. Section 6 reviews both experimental and theoretical aspects of the recently discovered phenomena of 'parity effect' and 'shell effect' that lead to a strong, non-monotonic size

Study of the interaction between the indentation size effect and Hall-Petch effect with spherical indenters on annealed polycrystalline copper

International Nuclear Information System (INIS)

Hou, X D; Bushby, A J; Jennett, N M

2008-01-01

Methods to obtain tensile stress-strain properties of materials from a practically non-destructive indentation test are of great industrial interest. Nanoindentation is a good candidate. However, to do this successfully, indentation size effects must be accounted for. An indentation size effect with spherical indenters has been shown for a range of fcc metals with relatively large grain size (Spary et al 2006 Phil. Mag. 86 5581-93); the increase in yield stress being proportional to the inverse cube root of indenter radius. Here, we investigate these differences further and present results for the indentation size effect with spherical indenters on Cu samples with a range of different grain sizes from 1 μm to single crystal. The important experimental control parameter, of the relative size of the indentation compared with the grain size, is also explored by using indenters of different radii on the different grain sized samples. When the grain size, d, is less than 6 times the radius of the projected contact area, a, a Hall-Petch-like behaviour is observed superimposed on the indentation size effect. For d > 6a the indentation size effect dominates. The two effects may be combined by addition in quadrature. This new parametric function is able to predict the indentation pressure in annealed copper given input values of indenter radius and grain size

Global Sales Training's Balancing Act

Science.gov (United States)

Boehle, Sarah

2010-01-01

A one-size-fits-all global sales strategy that fails to take into account the cultural, regulatory, geographic, and economic differences that exist across borders is a blueprint for failure. For training organizations tasked with educating globally dispersed sales forces, the challenge is adapting to these differences while simultaneously…

Effect of effective grain size on Charpy impact properties of high-strength bainitic steels

International Nuclear Information System (INIS)

Shin, Sang Yong; Han, Seung Youb; Lee, Sung Hak; Hwang, Byoung Chul; Lee, Chang Gil

2008-01-01

This study is concerned with the effect of Cu and B addition on microstructure and mechanical properties of high-strength bainitic steels. Six kinds of steels were fabricated by varying alloying elements and hot-rolling conditions, and their microstructures and tensile and Charpy impact properties were investigated. Their effective grain sizes were also characterized by the electron back-scatter diffraction analysis. The tensile test results indicated that the B- or Cu-containing steels had the higher yield and tensile strengths than the B- or Cu-free steels because their volume fractions of bainitic ferrite and martensite were quite high. The B- or Cu-free steels had the higher upper shelf energy than the B- or Cu-containing steels because of their higher volume fraction of granular bainite. In the steel containing 10 ppm B without Cu, the best combination of high strengths, high upper shelf energy, and low energy transition temperature could be obtained by the decrease in the overall effective grain size due to the presence of bainitic ferrite having smaller effective grain size

Effects of global and local contexts on chord processing: An ERP study.

Science.gov (United States)

Zhang, Jingjing; Zhou, Xuefeng; Chang, Ruohan; Yang, Yufang

2018-01-31

In real life, the processing of an incoming event is continuously influenced by prior information at multiple timescales. The present study investigated how harmonic contexts at both local and global levels influence the processing of an incoming chord in an event-related potentials experiment. Chord sequences containing two phrases were presented to musically trained listeners, with the last critical chord either harmonically related or less related to its preceding context at local and/or global levels. ERPs data showed an ERAN-like effect for local context in early time window and a N5-like component for later interaction between the local context and global context. These results suggest that both the local and global contexts influence the processing of an incoming music event, and the local effect happens earlier than the global. Moreover, the interaction between the local context and global context in N5 may suggest that music syntactic integration at local level takes place prior to the integration at global level. Copyright © 2017 Elsevier Ltd. All rights reserved.

Zero Flow Global Ischemia-Induced Injuries in Rat Heart Are Attenuated by Natural Honey

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Moslem Najafi

2012-06-01

Full Text Available Purpose: In the present study, effects of preischemic administration of natural honey on cardiac arrhythmias and myocardial infarction size during zero flow global ischemia were investigated in isolated rat heart. Methods:The isolated hearts were subjected to 30 min zero flow global ischemia followed by 120 min reperfusion then perfused by a modified drug free Krebs-Henseleit solution throughout the experiment (control or the solution containing 0.25, 0.5, 1 and 2% of natural honey for 15 min before induction of global ischemia (treated groups, respectively. Cardiac arrhythmias were determined based on the Lambeth conventions and the infarct size was measured by computerized planimetry. Results: Myocardial infarction size was 55.8±7.8% in the control group, while preischemic perfusion of honey (0.25, 0.5, 1 and 2% reduced it to 39.3±11, 30.6±5.5 (P<0.01, 17.9±5.6 (P<0.001 and 8.7±1.1% (P<0.001, respectively. A direct linear correlation between honey concentrations and infarction size reduction was observed (R2=0.9948. In addition, total number of ventricular ectopic beats were significantly decreased by all used concentrations of honey (P<0.05 during reperfusion time. Honey (0.25, 0.5 and 1 % also lowered incidence of irreversible ventricular fibrillation (P<0.05. Moreover, number and duration of ventricular tachycardia were reduced in all honey treated groups. Conclusion: Preischemic administration of natural honey before zero flow global ischemia can protect isolated rat heart against ischemia/reperfusion injuries as reduction of infarction size and arrhythmias. Maybe, antioxidant and free radical scavenging activities of honey, reduction of necrotized tissue and providing energy sources may involve in these cardioprotective effects of honey.

Size effects in olivine control strength in low-temperature plasticity regime

Science.gov (United States)

Kumamoto, K. M.; Thom, C.; Wallis, D.; Hansen, L. N.; Armstrong, D. E. J.; Goldsby, D. L.; Warren, J. M.; Wilkinson, A. J.

2017-12-01

The strength of the lithospheric mantle during deformation by low-temperature plasticity controls a range of geological phenomena, including lithospheric-scale strain localization, the evolution of friction on deep seismogenic faults, and the flexure of tectonic plates. However, constraints on the strength of olivine in this deformation regime are difficult to obtain from conventional rock-deformation experiments, and previous results vary considerably. We demonstrate via nanoindentation that the strength of olivine in the low-temperature plasticity regime is dependent on the length-scale of the test, with experiments on smaller volumes of material exhibiting larger yield stresses. This "size effect" has previously been explained in engineering materials as a result of the role of strain gradients and associated geometrically necessary dislocations in modifying plastic behavior. The Hall-Petch effect, in which a material with a small grain size exhibits a higher strength than one with a large grain size, is thought to arise from the same mechanism. The presence of a size effect resolves discrepancies among previous experimental measurements of olivine, which were either conducted using indentation methods or were conducted on polycrystalline samples with small grain sizes. An analysis of different low-temperature plasticity flow laws extrapolated to room temperature reveals a power-law relationship between length-scale (grain size for polycrystalline deformation and contact radius for indentation tests) and yield strength. This suggests that data from samples with large inherent length scales best represent the plastic strength of the coarse-grained lithospheric mantle. Additionally, the plastic deformation of nanometer- to micrometer-sized asperities on fault surfaces may control the evolution of fault roughness due to their size-dependent strength.

Effects of climate on size structure and functioning of aquatic food webs

NARCIS (Netherlands)

Lacerot, G.

2010-01-01

In aquatic food webs, the role of body size is notoriously strong. It is also well known that temperature has an effect on body size. For instance, Bergmann’s rule states that body size increases from warm to cold climates. This thesis addresses the question how climate shapes the size structure of

Introducing the Mean Absolute Deviation "Effect" Size

Science.gov (United States)

Gorard, Stephen

2015-01-01

This paper revisits the use of effect sizes in the analysis of experimental and similar results, and reminds readers of the relative advantages of the mean absolute deviation as a measure of variation, as opposed to the more complex standard deviation. The mean absolute deviation is easier to use and understand, and more tolerant of extreme…

Size effects on cavitation instabilities

DEFF Research Database (Denmark)

Niordson, Christian Frithiof; Tvergaard, Viggo

2006-01-01

growth is here analyzed for such cases. A finite strain generalization of a higher order strain gradient plasticity theory is applied for a power-law hardening material, and the numerical analyses are carried out for an axisymmetric unit cell containing a spherical void. In the range of high stress...... triaxiality, where cavitation instabilities are predicted by conventional plasticity theory, such instabilities are also found for the nonlocal theory, but the effects of gradient hardening delay the onset of the instability. Furthermore, in some cases the cavitation stress reaches a maximum and then decays...... as the void grows to a size well above the characteristic material length....

Global effects of local food-production crises: a virtual water perspective.

Science.gov (United States)

Tamea, Stefania; Laio, Francesco; Ridolfi, Luca

2016-01-25

By importing food and agricultural goods, countries cope with the heterogeneous global water distribution and often rely on water resources available abroad. The virtual displacement of the water used to produce such goods (known as virtual water) connects together, in a global water system, all countries participating to the international trade network. Local food-production crises, having social, economic or environmental origin, propagate in this network, modifying the virtual water trade and perturbing local and global food availability, quantified in terms of virtual water. We analyze here the possible effects of local crises by developing a new propagation model, parsimonious but grounded on data-based and statistically-verified assumptions, whose effectiveness is proved on the Argentinean crisis in 2008-09. The model serves as the basis to propose indicators of crisis impact and country vulnerability to external food-production crises, which highlight that countries with largest water resources have the highest impact on the international trade, and that not only water-scarce but also wealthy and globalized countries are among the most vulnerable to external crises. The temporal analysis reveals that global average vulnerability has increased over time and that stronger effects of crises are now found in countries with low food (and water) availability.

Effects of portion size on chronic energy intake

Directory of Open Access Journals (Sweden)

Pentel Paul R

2007-06-01

Full Text Available Abstract Background This study experimentally examined the effects of repeated exposure to different meal portion sizes on energy intake. Methods Nineteen employees of a county medical center were given free box lunches for two months, one month each of 1528 and 767 average kcal. Foods were identical in the two conditions, but differed in portion size. Meals averaged 44% calories from fat. Participants self-reported how much of each lunch was eaten. Unannounced 24-hour dietary recalls were also conducted by phone twice per week during each exposure period. Results Mean energy intake at the lunch meal was 332 kcal/day higher in large lunch than in small lunch periods (p Conclusion This study suggests that chronic exposure to large portion size meals can result in sustained increases in energy intake and may contribute to body weight increases over time.

EFFECTS OF EFFECTS OF PARTICLE SIZE DISTRIBUTION ...

African Journals Online (AJOL)

eobe

The parameters examined were: moisture content, particle size distribution, total isture content, particle size distribution, total hydrocarbon content, soil pH, available nitrogen, available phosphorus, total heterotrophic bacteria and fungi count. The analysis of the soil characteristics throughout the remediation period showed ...

Effect Size Analyses of Souvenaid in Patients with Alzheimer's Disease.

Science.gov (United States)

Cummings, Jeffrey; Scheltens, Philip; McKeith, Ian; Blesa, Rafael; Harrison, John E; Bertolucci, Paulo H F; Rockwood, Kenneth; Wilkinson, David; Wijker, Wouter; Bennett, David A; Shah, Raj C

2017-01-01

Souvenaid® (uridine monophosphate, docosahexaenoic acid, eicosapentaenoic acid, choline, phospholipids, folic acid, vitamins B12, B6, C, and E, and selenium), was developed to support the formation and function of neuronal membranes. To determine effect sizes observed in clinical trials of Souvenaid and to calculate the number needed to treat to show benefit or harm. Data from all three reported randomized controlled trials of Souvenaid in Alzheimer's disease (AD) dementia (Souvenir I, Souvenir II, and S-Connect) and an open-label extension study were included in analyses of effect size for cognitive, functional, and behavioral outcomes. Effect size was determined by calculating Cohen's d statistic (or Cramér's V method for nominal data), number needed to treat and number needed to harm. Statistical calculations were performed for the intent-to-treat populations. In patients with mild AD, effect sizes were 0.21 (95% confidence intervals: -0.06, 0.49) for the primary outcome in Souvenir II (neuropsychological test battery memory z-score) and 0.20 (0.10, 0.34) for the co-primary outcome of Souvenir I (Wechsler memory scale delayed recall). No effect was shown on cognition in patients with mild-to-moderate AD (S-Connect). The number needed to treat (6 and 21 for Souvenir I and II, respectively) and high number needed to harm values indicate a favorable harm:benefit ratio for Souvenaid versus control in patients with mild AD. The favorable safety profile and impact on outcome measures converge to corroborate the putative mode of action and demonstrate that Souvenaid can achieve clinically detectable effects in patients with early AD.

Effects of Telecoupling on Global Vegetation Dynamics

Science.gov (United States)

Viña, A.; Liu, J.

2016-12-01

With the ever increasing trend in telecoupling processes, such as international trade, all countries around the world are becoming more interdependent. However, the effects of this growing interdependence on vegetation (e.g., shifts in the geographic extent and distribution) remain unknown even though vegetation dynamics are crucially important for food production, carbon sequestration, provision of other ecosystem services, and biodiversity conservation. In this study we evaluate the effects of international trade on the spatio-temporal trajectories of vegetation at national and global scales, using vegetation index imagery collected over more than three decades by the Advanced Very High Resolution Radiometer (AVHRR) satellite sensor series together with concurrent national and international data on international trade (and its associated movement of people, goods, services and information). The spatio-temporal trajectories of vegetation are obtained using the scale of fluctuation technique, which is based on the decomposition of the AVHRR image time series to obtain information on its spatial dependence structure over time. Similar to the correlation length, the scale of fluctuation corresponds to the range over which fluctuations in the vegetation index are spatially correlated. Results indicate that global vegetation has changed drastically over the last three decades. These changes are not uniform across space, with hotspots in active trading countries. This study not only has direct implications for understanding global vegetation dynamics, but also sheds important insights on the complexity of human-nature interactions across telecoupled systems.

An Effective Model for Improving Global Health Nursing Competence.

Science.gov (United States)

Kang, Sun-Joo

2016-01-01

This paper proposed an effective model for improving global health nursing competence among undergraduate students. A descriptive case study was conducted by evaluation of four implemented programs by the author. All programs were conducted with students majoring in nursing and healthcare, where the researcher was a program director, professor, or facilitator. These programs were analyzed in terms of students' needs assessment, program design, and implementation and evaluation factors. The concept and composition of global nursing competence, identified within previous studies, were deemed appropriate in all of our programs. Program composition varied from curricular to extracurricular domains. During the implementation phase, some of the programs included non-Korean students to improve cultural diversity and overcome language barriers. Qualitative and quantitative surveys were conducted to assess program efficacy. Data triangulation from students' reflective journals was examined. Additionally, students' awareness regarding changes within global health nursing, improved critical thinking, cultural understanding, and global leadership skills were investigated pre- and post-program implementation. The importance of identifying students' needs regarding global nursing competence when developing appropriate curricula is discussed.

An Effective Model for Improving Global Health Nursing Competence

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Sunjoo Kang

2016-09-01

Full Text Available This paper developed an effective model for improving global health nursing competence among undergraduate students. A descriptive case study was conducted by implementing four programs. All programs were conducted with students majoring nursing and healthcare, where the researcher was a program director, professor, or facilitator. These programs were analyzed in terms of students’ needs assessment, program design, and implementation and evaluation factors. The concept and composition of global nursing competence, identified within previous studies, were deemed appropriate in all of our programs. Program composition varied from curricular to extracurricular domains. During the implementation phase, most of the programs included non-Korean students to improve cultural diversity and overcome language barriers. Qualitative and quantitative surveys were conducted to assess program efficacy. Data triangulation from students’ reflective journals was examined. Additionally, students’ awareness regarding changes within global health nursing, improved critical thinking, cultural understanding, and global leadership skills were investigated pre and post-program implementation. We discuss how identifying students’ needs regarding global nursing competence when developing appropriate curricula.

Enzymatic Degradation of Dynasan 114 SLN - Effect of Surfactants and Particle Size

International Nuclear Information System (INIS)

Olbrich, Carsten; Kayser, Oliver; Mueller, Rainer Helmut

2002-01-01

The degradation velocity of solid lipid nanoparticles (SLN) is - apart from drug diffusion - an important parameter determining drug release in vivo. To assess the effect of stabilizers systematically, Dynasan 114 SLN were produced with ionic surfactants (e.g. cholic acid sodium salt (NaCh), sodium dodecyl sulfate (SDS), cetylpyridiniumchloride (CPC)) and steric stabilizers (Tween 80, Poloxamer 188, 407 and Poloxamine 908) including a mixture of cholic acid sodium salt and Poloxamer 407. In addition, the size effects were investigated. The degradation velocity was measured using an in vitro lipase assay. SLN stabilized with lecithin and NaCh showed the fastest, Tween 80 the intermediate and the high molecular weight Poloxamer 407 the slowest degradation. Size effects were less pronounced for fast degrading particles (e.g. those stabilized with NaCh). No difference in the size range of 180-300-nm was observed, but a distinctly slower degradation of 800-nm SLN could be detected. For slowly degrading particles, more pronounced size effects were found. Size effects are more difficult to assess when the PCS diameters are similar, but small fractions of micrometer particles are present, besides the nanometer bulk population. The measured FFA formation is then a superposition of particles degrading at different speeds due to differences in the shape of the size distribution. Admixing of Poloxamer to NaCh had no delaying effect on the degradation of the Dynasan 114 SLN, indicating an influence of the nature of the lipid matrix that is affecting the stabilizers affinity to and anchoring onto the SLN surface

Transport, retention, and size perturbation of graphene oxide in saturated porous media: Effects of input concentration and grain size

Science.gov (United States)

Accurately predicting the fate and transport of graphene oxide (GO) in porous media is critical to assess its environmental impact. In this work, sand column experiments were conducted to determine the effect of input concentration and grain size on transport, retention, and size perturbation of GO ...

Satisfaction with support versus size of network: differential effects of social support on psychological distress in parents of pediatric cancer patients.

Science.gov (United States)

Harper, Felicity W K; Peterson, Amy M; Albrecht, Terrance L; Taub, Jeffrey W; Phipps, Sean; Penner, Louis A

2016-05-01

This study examined the direct and buffering effects of social support on longer-term global psychological distress among parents coping with pediatric cancer. In both sets of analyses, we examined whether these effects depended on the dimension of social support provided (i.e., satisfaction with support versus size of support network). Participants were 102 parents of pediatric cancer patients. At study entry, parents reported their trait anxiety, depression, and two dimensions of their social support network (satisfaction with support and size of support network). Parents subsequently reported their psychological distress in 3- and 9-month follow-up assessments. Parents' satisfaction with support had a direct effect on longer-term psychological distress; satisfaction was negatively associated with distress at both follow-ups. In contrast, size of support network buffered (moderated) the impact of trait anxiety and depression on later distress. Parents with smaller support networks and higher levels of trait anxiety and depression at baseline had higher levels of psychological distress at both follow-ups; for parents with larger support networks, there was no relationship. Social support can attenuate psychological distress in parents coping with pediatric cancer; however, the nature of the effect depends on the dimension of support. Whereas interventions that focus on increasing satisfaction with social support may benefit all parents, at-risk parents will likely benefit from interventions that ensure they have an adequate number of support resources. Copyright © 2015 John Wiley & Sons, Ltd.

Should we expect financial globalization to have significant effects on business cycles?

OpenAIRE

Iversen, Jens

2009-01-01

Empirical research suggests that financial globalization has insignificant effects on business cycles. Based on standard theoretical models it might be conjectured that the effects should be significant. I show that this conjecture is wrong. Theoretical effects of financial globalization can be determined to any level of precision by expanding the underlying artificial samples. In contrast, in the data the effects are imprecisely estimated because of short samples. I show that if the conclusi...

Preparing Students for Global Citizenship: The Effects of a Dutch Undergraduate Honors Course

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Ingrid W. Schutte

2017-01-01

Full Text Available Using a mixed method approach, this case study investigates effects on the participating students (N=25 of an undergraduate honors course in the Netherlands, aimed at global justice citizenship. Knowledge about effects of global citizenship courses is still limited. The Ethical Sensitivity Scale Questionnaire and the Global Citizenship Scale were used in a pre- and posttest design to measure possible development in the moral and civic domain among the participants of the course. In the qualitative part, deductive content analyses of students’ work and students’ written reflection on the course, utilizing the theory-based curriculum guidelines Global Justice Citizenship Education, were performed. In addition, a follow-up blog and interview were analyzed to learn students’ perception on the effects of the course after half a year. Quantitative results show increased ethical sensitivity as well as global civic engagement and global competence among the participants. Qualitative results point in the same direction and provide deeper insights in the content of students’ learning and the perceived impact of the course on their attitudes and behavior. Results are discussed in relation to theory on justice-oriented global citizenship and honors pedagogies.

Combined Effects of Ocean Warming and Acidification on Copepod Abundance, Body Size and Fatty Acid Content.

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Jessica Garzke

Full Text Available Concerns about increasing atmospheric CO2 concentrations and global warming have initiated studies on the consequences of multiple-stressor interactions on marine organisms and ecosystems. We present a fully-crossed factorial mesocosm study and assess how warming and acidification affect the abundance, body size, and fatty acid composition of copepods as a measure of nutritional quality. The experimental set-up allowed us to determine whether the effects of warming and acidification act additively, synergistically, or antagonistically on the abundance, body size, and fatty acid content of copepods, a major group of lower level consumers in marine food webs. Copepodite (developmental stages 1-5 and nauplii abundance were antagonistically affected by warming and acidification. Higher temperature decreased copepodite and nauplii abundance, while acidification partially compensated for the temperature effect. The abundance of adult copepods was negatively affected by warming. The prosome length of copepods was significantly reduced by warming, and the interaction of warming and CO2 antagonistically affected prosome length. Fatty acid composition was also significantly affected by warming. The content of saturated fatty acids increased, and the ratios of the polyunsaturated essential fatty acids docosahexaenoic- (DHA and arachidonic acid (ARA to total fatty acid content increased with higher temperatures. Additionally, here was a significant additive interaction effect of both parameters on arachidonic acid. Our results indicate that in a future ocean scenario, acidification might partially counteract some observed effects of increased temperature on zooplankton, while adding to others. These may be results of a fertilizing effect on phytoplankton as a copepod food source. In summary, copepod populations will be more strongly affected by warming rather than by acidifying oceans, but ocean acidification effects can modify some temperature impacts.

Size effect on deformation twinning in face-centred cubic single crystals: Experiments and modelling

International Nuclear Information System (INIS)

Liang, Z.Y.; De Hosson, J.T.M.; Huang, M.X.

2017-01-01

In addition to slip by dislocation glide, deformation twinning in small-sized metallic crystals also exhibits size effect, namely the twinning stress increases with decreasing sample size. In order to understand the underpinning mechanisms responsible for such effect, systematic experiments were carried out on the small-sized single-crystalline pillars of a twinning-induced plasticity steel with a face-centred cubic structure. The flow stress increases considerably with decreasing pillar diameter from 3 to 0.5 μm, demonstrating a substantial size effect with a power exponent of 0.43. Detailed microstructural characterization reveals that the plastic deformation of the present pillars is dominant by twinning, primarily via twin growth, indicating that the size effect should be related to deformation twinning instead of slip by dislocation glide. Subsequent modelling works indicate that twinning can be accomplished by the dissociation of the ion-radiation-induced vacancy Frank loops in the damaged subsurface layer of the pillars, and the size effect is attributed to the ion-radiation-induced compressive stress in the subsurface layer, which decreases with pillar diameter.

Effective Assimilation of Global Precipitation

Science.gov (United States)

Lien, G.; Kalnay, E.; Miyoshi, T.; Huffman, G. J.

2012-12-01

Assimilating precipitation observations by modifying the moisture and sometimes temperature profiles has been shown successful in forcing the model precipitation to be close to the observed precipitation, but only while the assimilation is taking place. After the forecast start, the model tends to "forget" the assimilation changes and lose their extra skill after few forecast hours. This suggests that this approach is not an efficient way to modify the potential vorticity field, since this is the variable that the model would remember. In this study, the ensemble Kalman filter (EnKF) method is used to effectively change the potential vorticity field by allowing ensemble members with better precipitation to receive higher weights. In addition to using an EnKF, two other changes in the precipitation assimilation process are proposed to solve the problems related to the highly non-Gaussian nature of the precipitation variable: a) transform precipitation into a Gaussian distribution based on its climatological distribution, and b) only assimilate precipitation at the location where some ensemble members have positive precipitation. The idea is first tested by the observing system simulation experiments (OSSEs) using SPEEDY, a simplified but realistic general circulation model. When the global precipitation is assimilated in addition to conventional rawinsonde observations, both the analyses and the medium range forecasts are significantly improved as compared to only having rawinsonde observations. The improvement is much reduced when only modifying the moisture field with the same approach, which shows the importance of the error covariance between precipitation and all other model variables. The effect of precipitation assimilation is larger in the Southern Hemisphere than that in the Northern Hemisphere because the Northern Hemisphere analyses are already accurate as a result of denser rawinsonde stations. Assimilation of precipitation using a more comprehensive

Continent-scale global change attribution in European birds - combining annual and decadal time scales

DEFF Research Database (Denmark)

Jørgensen, Peter Søgaard; Böhning-Gaese, Katrin; Thorup, Kasper

2016-01-01

foundation for attributing species responses to global change may be achieved by complementing an attributes-based approach by one estimating the relationship between repeated measures of organismal and environmental changes over short time scales. To assess the benefit of this multiscale perspective, we...... on or in the peak of the breeding season with the largest effect sizes observed in cooler parts of species' climatic ranges. Our results document the potential of combining time scales and integrating both species attributes and environmental variables for global change attribution. We suggest such an approach......Species attributes are commonly used to infer impacts of environmental change on multiyear species trends, e.g. decadal changes in population size. However, by themselves attributes are of limited value in global change attribution since they do not measure the changing environment. A broader...

Egg size and offspring quality: a meta-analysis in birds.

Science.gov (United States)

Krist, Miloš

2011-08-01

Parents affect offspring fitness by propagule size and quality, selection of oviposition site, quality of incubation, feeding of dependent young, and their defence against predators and parasites. Despite many case studies on each of these topics, this knowledge has not been rigorously integrated into individual parental care traits for any taxon. Consequently, we lack a comprehensive, quantitative assessment of how parental care modifies offspring phenotypes. This meta-analysis of 283 studies with 1805 correlations between egg size and offspring quality in birds is intended to fill this gap. The large sample size enabled testing of how the magnitude of the relationship between egg size and offspring quality depends on a number of variables. Egg size was positively related to nearly all studied offspring traits across all stages of the offspring life cycle. Not surprisingly, the relationship was strongest at hatching but persisted until the post-fledging stage. Morphological traits were the most closely related to egg size but significant relationships were also found with hatching success, chick survival, and growth rate. Non-significant effect sizes were found for egg fertility, chick immunity, behaviour, and life-history or sexual traits. Effect size did not depend on whether chicks were raised by their natural parents or were cross-fostered to other territories. Effect size did not depend on species-specific traits such as developmental mode, clutch size, and relative size of the egg, but was larger if tested in captive compared to wild populations and between rather than within broods. In sum, published studies support the view that egg size affects juvenile survival. There are very few studies that tested the relationship between egg size and the fecundity component of offspring fitness, and no studies on offspring survival as adults or on global fitness. More data are also needed for the relationships between egg size and offspring behavioural and

Effect size, confidence intervals and statistical power in psychological research.

Directory of Open Access Journals (Sweden)

Téllez A.

2015-07-01

Full Text Available Quantitative psychological research is focused on detecting the occurrence of certain population phenomena by analyzing data from a sample, and statistics is a particularly helpful mathematical tool that is used by researchers to evaluate hypotheses and make decisions to accept or reject such hypotheses. In this paper, the various statistical tools in psychological research are reviewed. The limitations of null hypothesis significance testing (NHST and the advantages of using effect size and its respective confidence intervals are explained, as the latter two measurements can provide important information about the results of a study. These measurements also can facilitate data interpretation and easily detect trivial effects, enabling researchers to make decisions in a more clinically relevant fashion. Moreover, it is recommended to establish an appropriate sample size by calculating the optimum statistical power at the moment that the research is designed. Psychological journal editors are encouraged to follow APA recommendations strictly and ask authors of original research studies to report the effect size, its confidence intervals, statistical power and, when required, any measure of clinical significance. Additionally, we must account for the teaching of statistics at the graduate level. At that level, students do not receive sufficient information concerning the importance of using different types of effect sizes and their confidence intervals according to the different types of research designs; instead, most of the information is focused on the various tools of NHST.

Smart Moves: Effects of Relative Brain Size on Establishment Success of Invasive Amphibians and Reptiles

Science.gov (United States)

Amiel, Joshua J.; Tingley, Reid; Shine, Richard

2011-01-01

Brain size relative to body size varies considerably among animals, but the ecological consequences of that variation remain poorly understood. Plausibly, larger brains confer increased behavioural flexibility, and an ability to respond to novel challenges. In keeping with that hypothesis, successful invasive species of birds and mammals that flourish after translocation to a new area tend to have larger brains than do unsuccessful invaders. We found the same pattern in ectothermic terrestrial vertebrates. Brain size relative to body size was larger in species of amphibians and reptiles reported to be successful invaders, compared to species that failed to thrive after translocation to new sites. This pattern was found in six of seven global biogeographic realms; the exception (where relatively larger brains did not facilitate invasion success) was Australasia. Establishment success was also higher in amphibian and reptile families with larger relative brain sizes. Future work could usefully explore whether invasion success is differentially associated with enlargement of specific parts of the brain (as predicted by the functional role of the forebrain in promoting behavioural flexibility), or with a general size increase (suggesting that invasion success is facilitated by enhanced perceptual and motor skills, as well as cognitive ability). PMID:21494328

Smart moves: effects of relative brain size on establishment success of invasive amphibians and reptiles.

Directory of Open Access Journals (Sweden)

Joshua J Amiel

2011-04-01

Full Text Available Brain size relative to body size varies considerably among animals, but the ecological consequences of that variation remain poorly understood. Plausibly, larger brains confer increased behavioural flexibility, and an ability to respond to novel challenges. In keeping with that hypothesis, successful invasive species of birds and mammals that flourish after translocation to a new area tend to have larger brains than do unsuccessful invaders. We found the same pattern in ectothermic terrestrial vertebrates. Brain size relative to body size was larger in species of amphibians and reptiles reported to be successful invaders, compared to species that failed to thrive after translocation to new sites. This pattern was found in six of seven global biogeographic realms; the exception (where relatively larger brains did not facilitate invasion success was Australasia. Establishment success was also higher in amphibian and reptile families with larger relative brain sizes. Future work could usefully explore whether invasion success is differentially associated with enlargement of specific parts of the brain (as predicted by the functional role of the forebrain in promoting behavioural flexibility, or with a general size increase (suggesting that invasion success is facilitated by enhanced perceptual and motor skills, as well as cognitive ability.

Aerosol size-dependent below-cloud scavenging by rain and snow in the ECHAM5-HAM

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R. Posselt

2009-07-01

Full Text Available Wet deposition processes are highly efficient in the removal of aerosols from the atmosphere, and thus strongly influence global aerosol concentrations, and clouds, and their respective radiative forcings. In this study, physically detailed size-dependent below-cloud scavenging parameterizations for rain and snow are implemented in the ECHAM5-HAM global aerosol-climate model. Previously, below-cloud scavenging by rain in the ECHAM5-HAM was simply a function of the aerosol mode, and then scaled by the rainfall rate. The below-cloud scavenging by snow was a function of the snowfall rate alone. The global mean aerosol optical depth, and sea salt burden are sensitive to the below-cloud scavenging coefficients, with reductions near to 15% when the more vigorous size-dependent below-cloud scavenging by rain and snow is implemented. The inclusion of a prognostic rain scheme significantly reduces the fractional importance of below-cloud scavenging since there is higher evaporation in the lower troposphere, increasing the global mean sea salt burden by almost 15%. Thermophoretic effects are shown to produce increases in the global and annual mean number removal of Aitken size particles of near to 10%, but very small increases (near 1% in the global mean below-cloud mass scavenging of carbonaceous and sulfate aerosols. Changes in the assumptions about the below-cloud scavenging by rain of particles with radius smaller than 10 nm do not cause any significant changes to the global and annual mean aerosol mass or number burdens, despite a change in the below-cloud number removal rate for nucleation mode particles by near to five-fold. Annual and zonal mean nucleation mode number concentrations are enhanced by up to 30% in the lower troposphere with the more vigourous size-dependent below-cloud scavenging. Closer agreement with different observations is found when the more physically detailed below-cloud scavenging parameterization is employed in the ECHAM5

Effective size of density-dependent two-sex populations: the effect of mating systems.

Science.gov (United States)

Myhre, A M; Engen, S; SAEther, B-E

2017-08-01

Density dependence in vital rates is a key feature affecting temporal fluctuations of natural populations. This has important implications for the rate of random genetic drift. Mating systems also greatly affect effective population sizes, but knowledge of how mating system and density regulation interact to affect random genetic drift is poor. Using theoretical models and simulations, we compare N e in short-lived, density-dependent animal populations with different mating systems. We study the impact of a fluctuating, density-dependent sex ratio and consider both a stable and a fluctuating environment. We find a negative relationship between annual N e /N and adult population size N due to density dependence, suggesting that loss of genetic variation is reduced at small densities. The magnitude of this decrease was affected by mating system and life history. A male-biased, density-dependent sex ratio reduces the rate of genetic drift compared to an equal, density-independent sex ratio, but a stochastic change towards male bias reduces the N e /N ratio. Environmental stochasticity amplifies temporal fluctuations in population size and is thus vital to consider in estimation of effective population sizes over longer time periods. Our results on the reduced loss of genetic variation at small densities, particularly in polygamous populations, indicate that density regulation may facilitate adaptive evolution at small population sizes. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Influences of population size and density on birthplace effects.

Science.gov (United States)

Hancock, David J; Coutinho, Patrícia; Côté, Jean; Mesquita, Isabel

2018-01-01

Contextual influences on talent development (e.g., birthplace effects) have become a topic of interest for sport scientists. Birthplace effects occur when being born in a certain city size leads to participation or performance advantages, typically for those born in smaller or mid-sized cities. The purpose of this study was to investigate birthplace effects in Portuguese volleyball players by analysing city size, as well as population density - an important but infrequently used variable. Participants included 4062 volleyball players (M age  = 33), 53.2% of whom were men. Using Portuguese national census data from 1981, we compared participants (within each sex) across five population categories. In addition, we used ANOVAs to study expertise and population density. Results indicated that men and women athletes born in districts of 200,000-399,999 were 2.4 times more likely to attain elite volleyball status, while all other districts decreased the odds of expert development. For men, being born in high-density areas resulted in less chance of achieving expertise, whereas there were no differences for women. The results suggest that athletes' infrastructure and social structure play an important role in talent development, and that these structures are influenced by total population and population density, respectively.

Surface bond contraction and its effect on the nanometric sized lead zirconate titanate

International Nuclear Information System (INIS)

Haitao Huang; Sun, Chang Q.; Hing, Peter

2000-01-01

The grain size effect of lead zirconate titanate PbZr 1-x Ti x O 3 (PZT, x≥0.6) caused by surface bond contraction has been investigated by using the Landau-Ginsburg-Devonshire (LGD) phenomenological theory. It has been shown that, due to the surface bond contraction, both the Curie temperature and the spontaneous polarization of tetragonal PZT decrease with decreasing grain size. These effects become more significant when the grain size is in the nanometre range. A dielectric anomaly appears with decreasing grain size, which corresponds to a size dependent phase transformation. The ferroelectric critical size below which a loss of ferroelectricity will happen is estimated from the results obtained. (author). Letter-to-the-editor

Size, rarity and charisma: valuing African wildlife trophies.

Directory of Open Access Journals (Sweden)

Paul J Johnson

Full Text Available We explore variation in the prices paid by recreational hunters of trophy animals in Africa and its possible causes, including perceived rarity. Previous work has raised the possibility that extinction can result if demand rises fast enough as a species becomes rarer. We attempt to disentangle this from other inter-correlated influences affecting price. Species with larger body sizes and larger trophies were more valuable. Value increased less steeply as a function of size for bovids than for felids and the effect was consistent across countries. Power laws, ubiquitous in physical and social systems, described the trends. The exponent was approximately 0.4 for bovids, compared with approximately 1.0 for felids. Rarity (as indexed by IUCN score influenced the value of bovid trophies - price was higher for species in categories denoting higher global threat. There was substantial variation in price among and within families not explained by either size or rarity. This may be attributable to a 'charisma' effect, which seems likely to be a general attribute of human perceptions of wildlife. Species where prices were higher than predicted by size or rarity are ranked high in published accounts of desirability by hunters. We conclude that the valuation of these species is explicable to a large extent by body size and perceived rarity, and that differences in valuation between taxonomic groups are related to less easily quantified 'charisma' effects. These findings are relevant for conservationists considering the threat status of species exploited in open access markets, and where license quotas are adjusted in response to changes in perceived rarity.

The effect of scaffold pore size in cartilage tissue engineering.

Science.gov (United States)

Nava, Michele M; Draghi, Lorenza; Giordano, Carmen; Pietrabissa, Riccardo

2016-07-26

The effect of scaffold pore size and interconnectivity is undoubtedly a crucial factor for most tissue engineering applications. The aim of this study was to examine the effect of pore size and porosity on cartilage construct development in different scaffolds seeded with articular chondrocytes. We fabricated poly-L-lactide-co-trimethylene carbonate scaffolds with different pore sizes, using a solvent-casting/particulate-leaching technique. We seeded primary bovine articular chondrocytes on these scaffolds, cultured the constructs for 2 weeks and examined cell proliferation, viability and cell-specific production of cartilaginous extracellular matrix proteins, including GAG and collagen. Cell density significantly increased up to 50% with scaffold pore size and porosity, likely facilitated by cell spreading on the internal surface of bigger pores, and by increased mass transport of gases and nutrients to cells, and catabolite removal from cells, allowed by lower diffusion barriers in scaffolds with a higher porosity. However, both the cell metabolic activity and the synthesis of cartilaginous matrix proteins significantly decreased by up to 40% with pore size. We propose that the association of smaller pore diameters, causing 3-dimensional cell aggregation, to a lower oxygenation caused by a lower porosity, could have been the condition that increased the cell-specific synthesis of cartilaginous matrix proteins in the scaffold with the smallest pores and the lowest porosity among those tested. In the initial steps of in vitro cartilage engineering, the combination of small scaffold pores and low porosity is an effective strategy with regard to the promotion of chondrogenesis.

Bayesian sample size determination for cost-effectiveness studies with censored data.

Directory of Open Access Journals (Sweden)

Daniel P Beavers

Full Text Available Cost-effectiveness models are commonly utilized to determine the combined clinical and economic impact of one treatment compared to another. However, most methods for sample size determination of cost-effectiveness studies assume fully observed costs and effectiveness outcomes, which presents challenges for survival-based studies in which censoring exists. We propose a Bayesian method for the design and analysis of cost-effectiveness data in which costs and effectiveness may be censored, and the sample size is approximated for both power and assurance. We explore two parametric models and demonstrate the flexibility of the approach to accommodate a variety of modifications to study assumptions.

Conserved regulators of nucleolar size revealed by global phenotypic analyses.

Science.gov (United States)

Neumüller, Ralph A; Gross, Thomas; Samsonova, Anastasia A; Vinayagam, Arunachalam; Buckner, Michael; Founk, Karen; Hu, Yanhui; Sharifpoor, Sara; Rosebrock, Adam P; Andrews, Brenda; Winston, Fred; Perrimon, Norbert

2013-08-20

Regulation of cell growth is a fundamental process in development and disease that integrates a vast array of extra- and intracellular information. A central player in this process is RNA polymerase I (Pol I), which transcribes ribosomal RNA (rRNA) genes in the nucleolus. Rapidly growing cancer cells are characterized by increased Pol I-mediated transcription and, consequently, nucleolar hypertrophy. To map the genetic network underlying the regulation of nucleolar size and of Pol I-mediated transcription, we performed comparative, genome-wide loss-of-function analyses of nucleolar size in Saccharomyces cerevisiae and Drosophila melanogaster coupled with mass spectrometry-based analyses of the ribosomal DNA (rDNA) promoter. With this approach, we identified a set of conserved and nonconserved molecular complexes that control nucleolar size. Furthermore, we characterized a direct role of the histone information regulator (HIR) complex in repressing rRNA transcription in yeast. Our study provides a full-genome, cross-species analysis of a nuclear subcompartment and shows that this approach can identify conserved molecular modules.

Conserved Regulators of Nucleolar Size Revealed by Global Phenotypic Analyses

Science.gov (United States)

Neumüller, Ralph A.; Gross, Thomas; Samsonova, Anastasia A.; Vinayagam, Arunachalam; Buckner, Michael; Founk, Karen; Hu, Yanhui; Sharifpoor, Sara; Rosebrock, Adam P.; Andrews, Brenda; Winston, Fred; Perrimon, Norbert

2014-01-01

Regulation of cell growth is a fundamental process in development and disease that integrates a vast array of extra- and intracellular information. A central player in this process is RNA polymerase I (Pol I), which transcribes ribosomal RNA (rRNA) genes in the nucleolus. Rapidly growing cancer cells are characterized by increased Pol I–mediated transcription and, consequently, nucleolar hypertrophy. To map the genetic network underlying the regulation of nucleolar size and of Pol I–mediated transcription, we performed comparative, genome-wide loss-of-function analyses of nucleolar size in Saccharomyces cerevisiae and Drosophila melanogaster coupled with mass spectrometry–based analyses of the ribosomal DNA (rDNA) promoter. With this approach, we identified a set of conserved and nonconserved molecular complexes that control nucleolar size. Furthermore, we characterized a direct role of the histone information regulator (HIR) complex in repressing rRNA transcription in yeast. Our study provides a full-genome, cross-species analysis of a nuclear subcompartment and shows that this approach can identify conserved molecular modules. PMID:23962978

Effect Size Measures for Differential Item Functioning in a Multidimensional IRT Model

Science.gov (United States)

Suh, Youngsuk

2016-01-01

This study adapted an effect size measure used for studying differential item functioning (DIF) in unidimensional tests and extended the measure to multidimensional tests. Two effect size measures were considered in a multidimensional item response theory model: signed weighted P-difference and unsigned weighted P-difference. The performance of…

Effect size and statistical power in the rodent fear conditioning literature – A systematic review

Science.gov (United States)

Macleod, Malcolm R.

2018-01-01

Proposals to increase research reproducibility frequently call for focusing on effect sizes instead of p values, as well as for increasing the statistical power of experiments. However, it is unclear to what extent these two concepts are indeed taken into account in basic biomedical science. To study this in a real-case scenario, we performed a systematic review of effect sizes and statistical power in studies on learning of rodent fear conditioning, a widely used behavioral task to evaluate memory. Our search criteria yielded 410 experiments comparing control and treated groups in 122 articles. Interventions had a mean effect size of 29.5%, and amnesia caused by memory-impairing interventions was nearly always partial. Mean statistical power to detect the average effect size observed in well-powered experiments with significant differences (37.2%) was 65%, and was lower among studies with non-significant results. Only one article reported a sample size calculation, and our estimated sample size to achieve 80% power considering typical effect sizes and variances (15 animals per group) was reached in only 12.2% of experiments. Actual effect sizes correlated with effect size inferences made by readers on the basis of textual descriptions of results only when findings were non-significant, and neither effect size nor power correlated with study quality indicators, number of citations or impact factor of the publishing journal. In summary, effect sizes and statistical power have a wide distribution in the rodent fear conditioning literature, but do not seem to have a large influence on how results are described or cited. Failure to take these concepts into consideration might limit attempts to improve reproducibility in this field of science. PMID:29698451

Effect of Particle Size on Thermal Conductivity of Nanofluid

Science.gov (United States)

Chopkar, M.; Sudarshan, S.; Das, P. K.; Manna, I.

2008-07-01

Nanofluids, containing nanometric metallic or oxide particles, exhibit extraordinarily high thermal conductivity. It is reported that the identity (composition), amount (volume percent), size, and shape of nanoparticles largely determine the extent of this enhancement. In the present study, we have experimentally investigated the impact of Al2Cu and Ag2Al nanoparticle size and volume fraction on the effective thermal conductivity of water and ethylene glycol based nanofluid prepared by a two-stage process comprising mechanical alloying of appropriate Al-Cu and Al-Ag elemental powder blend followed by dispersing these nanoparticles (1 to 2 vol pct) in water and ethylene glycol with different particle sizes. The thermal conductivity ratio of nanofluid, measured using an indigenously developed thermal comparator device, shows a significant increase of up to 100 pct with only 1.5 vol pct nanoparticles of 30- to 40-nm average diameter. Furthermore, an analytical model shows that the interfacial layer significantly influences the effective thermal conductivity ratio of nanofluid for the comparable amount of nanoparticles.

Effects of size and defects on the elasticity of silicon nanocantilevers

NARCIS (Netherlands)

Sadeghian, H.; Yang, C.K.; Goosen, J.F.L.; Bossche, A.; Staufer, U.; French, P.J.; Van Keulen, F.

2010-01-01

The size-dependent elastic behavior of silicon nanocantilevers and nanowires, specifically the effective Young’s modulus, has been determined by experimental measurements and theoretical investigations. The size dependence becomes more significant as the devices scale down from micro- to

Sensitivity of leaf size and shape to climate: Global patterns and paleoclimatic applications

Science.gov (United States)

Peppe, D.J.; Royer, D.L.; Cariglino, B.; Oliver, S.Y.; Newman, S.; Leight, E.; Enikolopov, G.; Fernandez-Burgos, M.; Herrera, F.; Adams, J.M.; Correa, E.; Currano, E.D.; Erickson, J.M.; Hinojosa, L.F.; Hoganson, J.W.; Iglesias, A.; Jaramillo, C.A.; Johnson, K.R.; Jordan, G.J.; Kraft, N.J.B.; Lovelock, E.C.; Lusk, C.H.; Niinemets, U.; Penuelas, J.; Rapson, G.; Wing, S.L.; Wright, I.J.

2011-01-01

Paleobotanists have long used models based on leaf size and shape to reconstruct paleoclimate. However, most models incorporate a single variable or use traits that are not physiologically or functionally linked to climate, limiting their predictive power. Further, they often underestimate paleotemperature relative to other proxies. Here we quantify leaf-climate correlations from 92 globally distributed, climatically diverse sites, and explore potential confounding factors. Multiple linear regression models for mean annual temperature (MAT) and mean annual precipitation (MAP) are developed and applied to nine well-studied fossil floras. We find that leaves in cold climates typically have larger, more numerous teeth, and are more highly dissected. Leaf habit (deciduous vs evergreen), local water availability, and phylogenetic history all affect these relationships. Leaves in wet climates are larger and have fewer, smaller teeth. Our multivariate MAT and MAP models offer moderate improvements in precision over univariate approaches (??4.0 vs 4.8??C for MAT) and strong improvements in accuracy. For example, our provisional MAT estimates for most North American fossil floras are considerably warmer and in better agreement with independent paleoclimate evidence. Our study demonstrates that the inclusion of additional leaf traits that are functionally linked to climate improves paleoclimate reconstructions. This work also illustrates the need for better understanding of the impact of phylogeny and leaf habit on leaf-climate relationships. ?? 2011 The Authors. New Phytologist ?? 2011 New Phytologist Trust.

Preparing students for global citizenship: the effects of a Dutch undergraduate honors course

NARCIS (Netherlands)

Schutte, Ingrid W.; Kamans, Elanor; Wolfensberger, Marca; Veugelers, Wiel

2017-01-01

Using a mixed method approach, this case study investigates effects on the participating students () of an undergraduate honors course in the Netherlands, aimed at global justice citizenship. Knowledge about effects of global citizenship courses is still limited. The Ethical Sensitivity Scale

Effects of Na and Ca on particle size; Effect of filtering on UV absorbance

Data.gov (United States)

U.S. Environmental Protection Agency — Effects of Na and Ca on particle size; Effect of filtering on UV absorbance. This dataset is associated with the following publication: Bouchard, D., C. Knightes, X....

Atomistic origin of size effects in fatigue behavior of metallic glasses

Science.gov (United States)

Sha, Zhendong; Wong, Wei Hin; Pei, Qingxiang; Branicio, Paulo Sergio; Liu, Zishun; Wang, Tiejun; Guo, Tianfu; Gao, Huajian

2017-07-01

While many experiments and simulations on metallic glasses (MGs) have focused on their tensile ductility under monotonic loading, the fatigue mechanisms of MGs under cyclic loading still remain largely elusive. Here we perform molecular dynamics (MD) and finite element simulations of tension-compression fatigue tests in MGs to elucidate their fatigue mechanisms with focus on the sample size effect. Shear band (SB) thickening is found to be the inherent fatigue mechanism for nanoscale MGs. The difference in fatigue mechanisms between macroscopic and nanoscale MGs originates from whether the SB forms partially or fully through the cross-section of the specimen. Furthermore, a qualitative investigation of the sample size effect suggests that small sample size increases the fatigue life while large sample size promotes cyclic softening and necking. Our observations on the size-dependent fatigue behavior can be rationalized by the Gurson model and the concept of surface tension of the nanovoids. The present study sheds light on the fatigue mechanisms of MGs and can be useful in interpreting previous experimental results.

Global Landslide Catalog Export

Data.gov (United States)

National Aeronautics and Space Administration — The Global Landslide Catalog (GLC) was developed with the goal of identifying rainfall-triggered landslide events around the world, regardless of size, impacts or...

THE EFFECTS OF SWINGS IN GLOBAL WHEAT PRICES ON THE DOMESTIC MARKETS IN AFGHANISTAN

Directory of Open Access Journals (Sweden)

Najibullah Hassanzoy

2016-10-01

Full Text Available The recent shocks in global prices of cereals and the spillover effects of trade restrictive policies adversely affected domestic markets, particularly in the net food importing countries such as Afghanistan. This paper investigates the effects of 2007–2008 spikes in global wheat prices on the dynamics of price transmission and long-run equilibrium relationship between global and domestic wheat markets. The findings indicate that domestic and global wheat markets may be cointegrated in Regime-I (pre-break, Regime-II (post-break and the overall sample period. Moreover, the elasticity of price transmission and speed of adjustment towards the long-run equilibrium are substantially different between the two regimes, i.e., they appear to be larger in Regime-I as compared to Regime-II. Similarly, the effect of a shock in global wheat prices on domestic wheat markets might be long-lasting in Regime-I but transitory in Regime-II. This research underlines the need for mitigating the adverse effect of spikes in global wheat prices on domestic wheat markets in the context of a landlocked net food importing country.

Zooming into creativity: individual differences in attentional global-local biases are linked to creative thinking.

Science.gov (United States)

Zmigrod, Sharon; Zmigrod, Leor; Hommel, Bernhard

2015-01-01

While recent studies have investigated how processes underlying human creativity are affected by particular visual-attentional states, we tested the impact of more stable attention-related preferences. These were assessed by means of Navon's global-local task, in which participants respond to the global or local features of large letters constructed from smaller letters. Three standard measures were derived from this task: the sizes of the global precedence effect, the global interference effect (i.e., the impact of incongruent letters at the global level on local processing), and the local interference effect (i.e., the impact of incongruent letters at the local level on global processing). These measures were correlated with performance in a convergent-thinking creativity task (the Remote Associates Task), a divergent-thinking creativity task (the Alternate Uses Task), and a measure of fluid intelligence (Raven's matrices). Flexibility in divergent thinking was predicted by the local interference effect while convergent thinking was predicted by intelligence only. We conclude that a stronger attentional bias to visual information about the "bigger picture" promotes cognitive flexibility in searching for multiple solutions.

Grain-size effects on thermal properties of BaTiO3 ceramics

Indian Academy of Sciences (India)

Administrator

decreasing grain size. Furthermore, the Curie temperature shifts to lower temperature with decreasing grain size. Keywords. Nanocrystalline ceramics; thermal properties; size effect. 1. Introduction. BaTiO3 has been widely used in the electronic industry for its high dielectric constant and low losses above room temperature ...

The size effect of searching window for measuring wavefront of laser beam

International Nuclear Information System (INIS)

Park, Seung Kyu; Baik, Sung Hoon; Lim, Chang Hwan; Kim, Jung Cheol; Yi, Seung Jun; Ra, Sung Woong

2003-01-01

We investigated the size effect of the searching window for measuring of a laser beam using a Shack-Hartmann sensor. The shapes of spot images on an acquired wavefront image by using a Shack-Hartmann sensor are usually imbalanced. Also, the distributed intensity pattern of each spot image is varied according to successively acquired wavefront image. We studied on the optimized size of searching window to get wavefront with high measurement resolution. We experimented on the various size effect of searching window on an acquired wavefront image to get fine wavefront information using a Shack-Hartmann sensor. As the experimental results, we proposed the optimum size of searching window to measure improved wavefront.

Paying attention to attention: evidence for an attentional contribution to the size congruity effect.

Science.gov (United States)

Risko, Evan F; Maloney, Erin A; Fugelsang, Jonathan A

2013-08-01

Understanding the mechanisms supporting our comprehension of magnitude information represents a key goal in cognitive psychology. A major phenomenon employed in the pursuit of this goal has been the physical size congruity effect-namely, the observation that comparing the relative numerical sizes of two numbers is influenced by their relative physical sizes. The standard account of the physical size congruity effect attributes it to the automatic influence of the comparison of irrelevant physical magnitudes on numerical judgments. Here we develop an alternative account of this effect on the basis of the operation of attention in the typical size congruity display and the temporal dynamics of number comparison. We also provide a test of a number of predictions derived from this alternative account by combining a physical size congruity manipulation with a manipulation designed to alter the operation of attention within the typical size congruity display (i.e., a manipulation of the relative onsets of the digits). This test provides evidence consistent with an attentional contribution to the size congruity effect. Implications for our understanding of magnitude and the interactions between attention and magnitude are discussed.

Short communication: Effective population size and inbreeding rate ...

African Journals Online (AJOL)

Short communication: Effective population size and inbreeding rate of indigenous Nguni cattle under in situ conservation in the low-input communal production ... as not at risk of extinction, while the individual enterprises were classified as being endangered-maintained without the exchange of germ plasm among them.

Global comparative healthcare effectiveness research: Evaluating sustainable programmes in low & middle resource settings

Directory of Open Access Journals (Sweden)

Rajesh Balkrishnan

2013-01-01

Full Text Available The need to focus healthcare expenditures on innovative and sustainable health systems that efficiently use existing effective therapies are the major drivers stimulating Comparative Effectiveness Research (CER across the globe. Lack of adequate access and high cost of essential medicines and technologies in many countries increases morbidity and mortality and cost of care that forces people and families into poverty due to disability and out-of-pocket expenses. This review illustrates the potential of value-added global health care comparative effectiveness research in shaping health systems and health care delivery paradigms in the "global south". Enabling the development of effective CER systems globally paves the way for tangible local and regional definitions of equity in health care because CER fosters the sharing of critical assets, resources, skills, and capabilities and the development of collaborative of multi-sectorial frameworks to improve health outcomes and metrics globally.

Effects of Aperture Size on Q factor and Shielding Effectiveness of a Cubic Resonator

Directory of Open Access Journals (Sweden)

S. Parr

2017-09-01

Full Text Available The EMC properties of a cubic metallic shield are highly affected by its resonances. At the resonant frequencies, the shielding effectiveness (SE collapses, which results in high field strengths inside the cavity. This can cause failure or even breakdown of electronic devices inside the shield. The resonant behaviour is mainly determined by the quality or Q factor of the shield. In this paper, the effects of the aperture size on the Q factor and the SE of an electrically large, cubic shield are analysed. At first, a method is developed in order to determine the Q factor based on the resonance behaviour of the shield in time domain. Only the first resonance of the shield is considered therefore. The results are evaluated for different aperture diameters and compared with theory for the Q factor. The dominant coupling mechanism of electromagnetic energy into the shield is thus identified. Then the effect of aperture size on the SE is analysed. The excitation of resonances is very probable if the interfering signal is an ultrawideband (UWB pulse, which constitutes a typical intentional electromagnetic interference (IEMI scenario. Therefore, the relation between aperture size and SE is analysed using the theory of the transient SE for a broadband signal with a constant spectral density distribution. The results show, that a worst case aperture size exists, where the SE has its minimum.

A review of finite size effects in quasi-zero dimensional superconductors

International Nuclear Information System (INIS)

Bose, Sangita; Ayyub, Pushan

2014-01-01

Quantum confinement and surface effects (SEs) dramatically modify most solid state phenomena as one approaches the nanometer scale, and superconductivity is no exception. Though we may expect significant modifications from bulk superconducting properties when the system dimensions become smaller than the characteristic length scales for bulk superconductors—such as the coherence length or the penetration depth—it is now established that there is a third length scale which ultimately determines the critical size at which Cooper pairing is destroyed. In quasi-zero-dimensional (0D) superconductors (e.g. nanocrystalline materials, isolated or embedded nanoparticles), one may define a critical particle diameter below which the mean energy level spacing arising from quantum confinement becomes equal to the bulk superconducting energy gap. The so-called Anderson criterion provides a remarkably accurate estimate of the limiting size for the destabilization of superconductivity in nanosystems. This review of size effects in quasi-0D superconductors is organized as follows. A general summary of size effects in nanostructured superconductors (section 1) is followed by a brief overview of their synthesis (section 2) and characterization using a variety of techniques (section 3). Section 4 reviews the size-evolution of important superconducting parameters—the transition temperature, critical fields and critical current—as the Anderson limit is approached from above. We then discuss the effect of thermodynamic fluctuations (section 5), which become significant in confined systems. Improvements in fabrication methods and the increasing feasibility of addressing individual nanoparticles using scanning probe techniques have lately opened up new directions in the study of nanoscale superconductivity. Section 6 reviews both experimental and theoretical aspects of the recently discovered phenomena of ‘parity effect’ and ‘shell effect’ that lead to a strong, non

Global non-linear effect of temperature on economic production.

Science.gov (United States)

Burke, Marshall; Hsiang, Solomon M; Miguel, Edward

2015-11-12

Growing evidence demonstrates that climatic conditions can have a profound impact on the functioning of modern human societies, but effects on economic activity appear inconsistent. Fundamental productive elements of modern economies, such as workers and crops, exhibit highly non-linear responses to local temperature even in wealthy countries. In contrast, aggregate macroeconomic productivity of entire wealthy countries is reported not to respond to temperature, while poor countries respond only linearly. Resolving this conflict between micro and macro observations is critical to understanding the role of wealth in coupled human-natural systems and to anticipating the global impact of climate change. Here we unify these seemingly contradictory results by accounting for non-linearity at the macro scale. We show that overall economic productivity is non-linear in temperature for all countries, with productivity peaking at an annual average temperature of 13 °C and declining strongly at higher temperatures. The relationship is globally generalizable, unchanged since 1960, and apparent for agricultural and non-agricultural activity in both rich and poor countries. These results provide the first evidence that economic activity in all regions is coupled to the global climate and establish a new empirical foundation for modelling economic loss in response to climate change, with important implications. If future adaptation mimics past adaptation, unmitigated warming is expected to reshape the global economy by reducing average global incomes roughly 23% by 2100 and widening global income inequality, relative to scenarios without climate change. In contrast to prior estimates, expected global losses are approximately linear in global mean temperature, with median losses many times larger than leading models indicate.

Global non-linear effect of temperature on economic production

Science.gov (United States)

Burke, Marshall; Hsiang, Solomon M.; Miguel, Edward

2015-11-01

Growing evidence demonstrates that climatic conditions can have a profound impact on the functioning of modern human societies, but effects on economic activity appear inconsistent. Fundamental productive elements of modern economies, such as workers and crops, exhibit highly non-linear responses to local temperature even in wealthy countries. In contrast, aggregate macroeconomic productivity of entire wealthy countries is reported not to respond to temperature, while poor countries respond only linearly. Resolving this conflict between micro and macro observations is critical to understanding the role of wealth in coupled human-natural systems and to anticipating the global impact of climate change. Here we unify these seemingly contradictory results by accounting for non-linearity at the macro scale. We show that overall economic productivity is non-linear in temperature for all countries, with productivity peaking at an annual average temperature of 13 °C and declining strongly at higher temperatures. The relationship is globally generalizable, unchanged since 1960, and apparent for agricultural and non-agricultural activity in both rich and poor countries. These results provide the first evidence that economic activity in all regions is coupled to the global climate and establish a new empirical foundation for modelling economic loss in response to climate change, with important implications. If future adaptation mimics past adaptation, unmitigated warming is expected to reshape the global economy by reducing average global incomes roughly 23% by 2100 and widening global income inequality, relative to scenarios without climate change. In contrast to prior estimates, expected global losses are approximately linear in global mean temperature, with median losses many times larger than leading models indicate.

Intergenic DNA sequences from the human X chromosome reveal high rates of global gene flow

Directory of Open Access Journals (Sweden)

Wall Jeffrey D

2008-11-01

Full Text Available Abstract Background Despite intensive efforts devoted to collecting human polymorphism data, little is known about the role of gene flow in the ancestry of human populations. This is partly because most analyses have applied one of two simple models of population structure, the island model or the splitting model, which make unrealistic biological assumptions. Results Here, we analyze 98-kb of DNA sequence from 20 independently evolving intergenic regions on the X chromosome in a sample of 90 humans from six globally diverse populations. We employ an isolation-with-migration (IM model, which assumes that populations split and subsequently exchange migrants, to independently estimate effective population sizes and migration rates. While the maximum effective size of modern humans is estimated at ~10,000, individual populations vary substantially in size, with African populations tending to be larger (2,300–9,000 than non-African populations (300–3,300. We estimate mean rates of bidirectional gene flow at 4.8 × 10-4/generation. Bidirectional migration rates are ~5-fold higher among non-African populations (1.5 × 10-3 than among African populations (2.7 × 10-4. Interestingly, because effective sizes and migration rates are inversely related in African and non-African populations, population migration rates are similar within Africa and Eurasia (e.g., global mean Nm = 2.4. Conclusion We conclude that gene flow has played an important role in structuring global human populations and that migration rates should be incorporated as critical parameters in models of human demography.

Meta-Analysis of Effect Sizes Reported at Multiple Time Points Using General Linear Mixed Model

Science.gov (United States)

Musekiwa, Alfred; Manda, Samuel O. M.; Mwambi, Henry G.; Chen, Ding-Geng

2016-01-01

Meta-analysis of longitudinal studies combines effect sizes measured at pre-determined time points. The most common approach involves performing separate univariate meta-analyses at individual time points. This simplistic approach ignores dependence between longitudinal effect sizes, which might result in less precise parameter estimates. In this paper, we show how to conduct a meta-analysis of longitudinal effect sizes where we contrast different covariance structures for dependence between effect sizes, both within and between studies. We propose new combinations of covariance structures for the dependence between effect size and utilize a practical example involving meta-analysis of 17 trials comparing postoperative treatments for a type of cancer, where survival is measured at 6, 12, 18 and 24 months post randomization. Although the results from this particular data set show the benefit of accounting for within-study serial correlation between effect sizes, simulations are required to confirm these results. PMID:27798661

Comparing Forecasts of the Global Impacts of Climate Change

International Nuclear Information System (INIS)

Mendelsohn, R.; Williams, L.

2004-01-01

This paper utilizes the predictions of several Atmosphere-Ocean General Circulation Models and the Global Impact Model to create forecasts of the global market impacts from climate change. The forecasts of market impacts in 2100 vary considerably depending on climate scenarios and climate impact sensitivity. The models do concur that tropical nations will be hurt, temperate nations will be barely affected, and high latitude nations will benefit. Although the size of these effects varies a great deal across models, the beneficial and harmful effects are offsetting, so that the net impact on the globe is relatively small in almost all outcomes. Looking only at market impacts, the forecasts suggest that while the global net benefits of abatement are small, the distribution of damages suggests a large equity problem that could be addressed through a compensation program. The large uncertainty surrounding these forecasts further suggests that continued monitoring of both the climate and impacts is worthwhile

Effect of size on fracture and tensile manipulation of gold nanowires

International Nuclear Information System (INIS)

Wang, Fenying; Dai, Yanfeng; Zhao, Jianwei; Li, Qianjin; Zhang, Bin

2014-01-01

The fracture of metallic nanowires has attracted much attention owing to its reliability of application in nanoelectromechanical system. In this paper, we studied the fracture of [100] single-crystal gold nanowire subjected to uniaxial tension. The statistical breaking position distributions showed that the size effects had dominated the deformation and fracture of nanowires, and the quasi-static tensile deformations are insensitive to the styles of tensile rates. Furthermore, it was observed that the small-sized nanowire broke in the middle with disordered crystalline structure; for the middle-sized nanowire, although slippage plane had maintained the lattice degree, the fracture also happened in the middle due to symmetric tension; for the large-sized nanowire, the slippage was destroyed by symmetric tension, which induced the broken neck at one end of the nanowire. When the nanowire width is less than 5a (“a” means lattice constant, 0.408 nm for gold), the mechanical strength is relatively strong with obvious uncertainty, which can be attributed to the surface atom effect; when the width is larger than 5a, the influence of size on the mechanical property is more obvious at the constant strain rate than that at the absolute rate. Finally, the mechanical strength of the nanowire decreases with the size increasing

Theory of critical phenomena in finite-size systems scaling and quantum effects

CERN Document Server

Brankov, Jordan G; Tonchev, Nicholai S

2000-01-01

The aim of this book is to familiarise the reader with the rich collection of ideas, methods and results available in the theory of critical phenomena in systems with confined geometry. The existence of universal features of the finite-size effects arising due to highly correlated classical or quantum fluctuations is explained by the finite-size scaling theory. This theory (1) offers an interpretation of experimental results on finite-size effects in real systems; (2) gives the most reliable tool for extrapolation to the thermodynamic limit of data obtained by computer simulations; (3) reveals

Ionic Size Effects: Generalized Boltzmann Distributions, Counterion Stratification, and Modified Debye Length.

Science.gov (United States)

Liu, Bo; Liu, Pei; Xu, Zhenli; Zhou, Shenggao

2013-10-01

Near a charged surface, counterions of different valences and sizes cluster; and their concentration profiles stratify. At a distance from such a surface larger than the Debye length, the electric field is screened by counterions. Recent studies by a variational mean-field approach that includes ionic size effects and by Monte Carlo simulations both suggest that the counterion stratification is determined by the ionic valence-to-volume ratios. Central in the mean-field approach is a free-energy functional of ionic concentrations in which the ionic size effects are included through the entropic effect of solvent molecules. The corresponding equilibrium conditions define the generalized Boltzmann distributions relating the ionic concentrations to the electrostatic potential. This paper presents a detailed analysis and numerical calculations of such a free-energy functional to understand the dependence of the ionic charge density on the electrostatic potential through the generalized Boltzmann distributions, the role of ionic valence-to-volume ratios in the counterion stratification, and the modification of Debye length due to the effect of ionic sizes.

Global effects of scalar matter production in quantum cosmology

International Nuclear Information System (INIS)

Barvinskij, A.O.; Ponomarev, V.N.

1978-01-01

Within the framework of the geometrodynamical approach global effects of the production of scalar matter filling the closed uniform Friedman Universe are considered. The physical situation is discussed, which corresponds to such a scale of space-time intervals and energies, at which the matter is essentially quantum and the quantized gravitational field is within the quasi-classical limits when its spatial inhomogeneities are small and only global quantum effects are considerable. The only dynamic variable of the gravitational field is the Friedman Universe radius. The main principles of the formalism of the canonical superspace quantization of gravitational and material fields are considered. The method shows the applicability limits of the field theory on the background of classical geometry and leads to the principally new types of interaction

Effect of particle size of granules on some mechanical properties of ...

African Journals Online (AJOL)

Solid dosage forms are invariably multiparticulate systems of heterogenous particle size distribution. The purpose of this study was to investigate the effect of particle size distribution of paracetamol granules on some tablet mechanical properties of paracetamol tablets. Granules were formed by wet massing paracetamol ...

Size effects of latex nanomaterials on lung inflammation in mice

International Nuclear Information System (INIS)

Inoue, Ken-ichiro; Takano, Hirohisa; Yanagisawa, Rie; Koike, Eiko; Shimada, Akinori

2009-01-01

Effects of nano-sized materials (nanomaterials) on sensitive population have not been well elucidated. This study examined the effects of pulmonary exposure to (latex) nanomaterials on lung inflammation related to lipopolysaccharide (LPS) or allergen in mice, especially in terms of their size-dependency. In protocol 1, ICR male mice were divided into 8 experimental groups that intratracheally received a single exposure to vehicle, latex nanomaterials (250 μg/animal) with three sizes (25, 50, and 100 nm), LPS (75 μg/animal), or LPS plus latex nanomaterials. In protocol 2, ICR male mice were divided into 8 experimental groups that intratracheally received repeated exposure to vehicle, latex nanomaterials (100 μg/animal), allergen (ovalbumin: OVA; 1 μg/animal), or allergen plus latex nanomaterials. In protocol 1, latex nanomaterials with all sizes exacerbated lung inflammation elicited by LPS, showing an overall trend of amplified lung expressions of proinflammatory cytokines. Furthermore, LPS plus nanomaterials, especially with size less than 50 nm, significantly elevated circulatory levels of fibrinogen, macrophage chemoattractant protein-1, and keratinocyte-derived chemoattractant, and von Willebrand factor as compared with LPS alone. The enhancement tended overall to be greater with the smaller nanomaterials than with the larger ones. In protocol 2, latex nanomaterials with all sizes did not significantly enhance the pathophysiology of allergic asthma, characterized by eosinophilic lung inflammation and Igs production, although latex nanomaterials with less than 50 nm significantly induced/enhanced neutrophilic lung inflammation. These results suggest that latex nanomaterials differentially affect two types of (innate and adaptive immunity-dominant) lung inflammation

Processing vertical size disparities in distinct depth planes.

Science.gov (United States)

Duke, Philip A; Howard, Ian P

2012-08-17

A textured surface appears slanted about a vertical axis when the image in one eye is horizontally enlarged relative to the image in the other eye. The surface appears slanted in the opposite direction when the same image is vertically enlarged. Two superimposed textured surfaces with different horizontal size disparities appear as two surfaces that differ in slant. Superimposed textured surfaces with equal and opposite vertical size disparities appear as a single frontal surface. The vertical disparities are averaged. We investigated whether vertical size disparities are averaged across two superimposed textured surfaces in different depth planes or whether they induce distinct slants in the two depth planes. In Experiment 1, two superimposed textured surfaces with different vertical size disparities were presented in two depth planes defined by horizontal disparity. The surfaces induced distinct slants when the horizontal disparity was more than ±5 arcmin. Thus, vertical size disparities are not averaged over surfaces with different horizontal disparities. In Experiment 2 we confirmed that vertical size disparities are processed in surfaces away from the horopter, so the results of Experiment 1 cannot be explained by the processing of vertical size disparities in a fixated surface only. Together, these results show that vertical size disparities are processed separately in distinct depth planes. The results also suggest that vertical size disparities are not used to register slant globally by their effect on the registration of binocular direction of gaze.

Size effects and strain localization in atomic-scale cleavage modeling

International Nuclear Information System (INIS)

Elsner, B A M; Müller, S

2015-01-01

In this work, we study the adhesion and decohesion of Cu(1 0 0) surfaces using density functional theory (DFT) calculations. An upper stress to surface decohesion is obtained via the universal binding energy relation (UBER), but the model is limited to rigid separation of bulk-terminated surfaces. When structural relaxations are included, an unphysical size effect arises if decohesion is considered to occur as soon as the strain energy equals the energy of the newly formed surfaces. We employ the nudged elastic band (NEB) method to show that this size effect is opposed by a size-dependency of the energy barriers involved in the transition. Further, we find that the transition occurs via a localization of bond strain in the vicinity of the cleavage plane, which resembles the strain localization at the tip of a sharp crack that is predicted by linear elastic fracture mechanics. (paper)

Orientation dependent size effects in single crystalline anisotropic nanoplates with regard to surface energy

International Nuclear Information System (INIS)

Assadi, Abbas; Salehi, Manouchehr; Akhlaghi, Mehdi

2015-01-01

In this work, size dependent behavior of single crystalline normal and auxetic anisotropic nanoplates is discussed with consideration of material surface stresses via a generalized model. Bending of pressurized nanoplates and their fundamental resonant frequency are discussed for different crystallographic directions and anisotropy degrees. It is explained that the orientation effects are considerable when the nanoplates' edges are pinned but for clamped nanoplates, the anisotropy effect may be ignored. The size effects are the highest when the simply supported nanoplates are parallel to [110] direction but as the anisotropy gets higher, the size effects are reduced. The orientation effect is also discussed for possibility of self-instability occurrence in nanoplates. The results in simpler cases are compared with previous experiments for nanowires but with a correction factor. There are still some open questions for future studies. - Highlights: • Size effects in single crystalline anisotropic nanoplates are discussed. • A generalized model is established containing some physical assumptions. • Orientation dependent size effects due to material anisotropy are explained. • Bending, instability and frequencies are studied at normal/auxetic domain

Global biogeography of seed dormancy is determined by seasonality and seed size: a case study in the legumes.

Science.gov (United States)

Rubio de Casas, Rafael; Willis, Charles G; Pearse, William D; Baskin, Carol C; Baskin, Jerry M; Cavender-Bares, Jeannine

2017-06-01

Seed dormancy is expected to provide ecological advantages by adjusting germination to the favorable growth period. However, many species produce nondormant seeds, particularly in wet tropical forests, a biogeographic pattern that is not well accounted for in current models. We hypothesized that the global distribution of dormant seeds derives from their adaptive value in predictably fluctuating (i.e. seasonal) environments. However, the advantage conferred by dormancy might ultimately depend on other seed attributes, particularly size. This general model was tested within a phylogenetically informed framework using a data set comprising > 216 000 world-wide observations of Fabaceae, spanning three orders of magnitude in seed size and including both dormant and nondormant seeds. Our results confirmed our hypothesis: nondormant seeds can only evolve in climates with long growing seasons and/or in lineages that produce larger seeds. Conversely, dormancy should be evolutionarily stable in temperate lineages with small seeds. When the favorable season is fleeting, seed dormancy is the only adaptive strategy. Based on these results, we predict that, within a given lineage, taxa producing larger, nondormant seeds will necessarily predominate in aseasonal environments, while plants bearing small, dormant seeds will be dominant under short growing seasons. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Short communication Effective population size and inbreeding rate ...

African Journals Online (AJOL)

201010100

2013-05-30

May 30, 2013 ... Understanding and estimating effective population size for practical application in marine species management. Conservation Biology 25 (3), 438-449. Mapiye, C., Chimonyo, M., Muchenje, V., Dzama, K., Marufu, M.C. & Raats, J.G., 2007. Potential for value-addition of Nguni cattle products in the communal ...

Global precedence effects account for individual differences in both face and object recognition performance.

Science.gov (United States)

Gerlach, Christian; Starrfelt, Randi

2018-03-20

There has been an increase in studies adopting an individual difference approach to examine visual cognition and in particular in studies trying to relate face recognition performance with measures of holistic processing (the face composite effect and the part-whole effect). In the present study we examine whether global precedence effects, measured by means of non-face stimuli in Navon's paradigm, can also account for individual differences in face recognition and, if so, whether the effect is of similar magnitude for faces and objects. We find evidence that global precedence effects facilitate both face and object recognition, and to a similar extent. Our results suggest that both face and object recognition are characterized by a coarse-to-fine temporal dynamic, where global shape information is derived prior to local shape information, and that the efficiency of face and object recognition is related to the magnitude of the global precedence effect.

Effects of emulsion droplet sizes on the crystallisation of milk fat.

Science.gov (United States)

Truong, Tuyen; Bansal, Nidhi; Sharma, Ranjan; Palmer, Martin; Bhandari, Bhesh

2014-02-15

The crystallisation properties of milk fat emulsions containing dairy-based ingredients as functions of emulsion droplet size, cooling rate, and emulsifier type were investigated using a differential scanning calorimeter (DSC). Anhydrous milk fat and its fractions (stearin and olein) were emulsified with whey protein concentrate, sodium caseinate, and Tween80 by homogenisation to produce emulsions in various size ranges (0.13-3.10 μm). Particle size, cooling rate, and types of emulsifier all had an influence on the crystallisation properties of fat in the emulsions. In general, the crystallisation temperature of emulsified fats decreased with decreasing average droplet size and was of an exponent function of size, indicating that the influence of particle size on crystallisation temperature is more pronounced in the sub-micron range. This particle size effect was also verified by electron microscopy. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of particle size and distribution of the sizing agent on the carbon fibers surface and interfacial shear strength (IFSS) of its composites

International Nuclear Information System (INIS)

Zhang, R.L.; Liu, Y.; Huang, Y.D.; Liu, L.

2013-01-01

Effect of particle size and distribution of the sizing agent on the performance of carbon fiber and carbon fiber composites has been investigated. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to characterize carbon fiber surface topographies. At the same time, the single fiber strength and Weibull distribution were also studied in order to investigate the effect of coatings on the fibers. The interfacial shear strength and hygrothermal aging of the carbon fiber/epoxy resin composites were also measured. The results indicated that the particle size and distribution is important for improving the surface of carbon fibers and its composites performance. Different particle size and distribution of sizing agent has different contribution to the wetting performance of carbon fibers. The fibers sized with P-2 had higher value of IFSS and better hygrothermal aging resistant properties.

Effect Size (Cohen's d of Cognitive Screening Instruments Examined in Pragmatic Diagnostic Accuracy Studies

Directory of Open Access Journals (Sweden)

Andrew J. Larner

2014-07-01

Full Text Available Background/Aims: Many cognitive screening instruments (CSI are available to clinicians to assess cognitive function. The optimal method comparing the diagnostic utility of such tests is uncertain. The effect size (Cohen's d, calculated as the difference of the means of two groups divided by the weighted pooled standard deviations of these groups, may permit such comparisons. Methods: Datasets from five pragmatic diagnostic accuracy studies, which examined the Mini-Mental State Examination (MMSE, the Mini-Mental Parkinson (MMP, the Six-Item Cognitive Impairment Test (6CIT, the Montreal Cognitive Assessment (MoCA, the Test Your Memory test (TYM, and the Addenbrooke's Cognitive Examination-Revised (ACE-R, were analysed to calculate the effect size (Cohen's d for the diagnosis of dementia versus no dementia and for the diagnosis of mild cognitive impairment versus no dementia (subjective memory impairment. Results: The effect sizes for dementia versus no dementia diagnosis were large for all six CSI examined (range 1.59-1.87. For the diagnosis of mild cognitive impairment versus no dementia, the effect sizes ranged from medium to large (range 0.48-1.45, with MoCA having the largest effect size. Conclusion: The calculation of the effect size (Cohen's d in diagnostic accuracy studies is straightforward. The routine incorporation of effect size calculations into diagnostic accuracy studies merits consideration in order to facilitate the comparison of the relative value of CSI.

Effect of microfluidization on casein micelle size of bovine milk

Science.gov (United States)

Sinaga, H.; Deeth, H.; Bhandari, B.

2018-02-01

The properties of milk are likely to be dependent on the casein micelle size, and various processing technologies produce particular change in the average size of casein micelles. The main objective of this study was to manipulate casein micelle size by subjecting milk to microfluidizer. The experiment was performed as a complete block randomised design with three replications. The sample was passed through the microfluidizer at the set pressure of 83, 97, 112 and 126 MPa for one, two, three, four, five and six cycles, except for the 112 MPa. The results showed that microfluidized milk has smaller size by 3% with pressure up to 126 MPa. However, at each pressure, no further reduction was observed after increasing the passed up to 6 cycles. Although the average casein micelle size was similar, elevating pressure resulted in narrower size distribution. In contrast, increasing the number of cycles had little effect on casein micelle distribution. The finding from this study can be applied for future work to characterize the fundamental and functional properties of the treated milk.

Effect of geometric base roughness on size segregation

Directory of Open Access Journals (Sweden)

Jing L.

2017-01-01

Full Text Available The geometric roughness at boundaries has a profound impact on the dynamics of granular flows. For a bumpy base made of fixed particles, two major factors have been separately studied in the literature, namely, the size and spatial distribution of base particles. A recent work (Jing et al. 2016 has proposed a roughness indicator Ra, which combines both factors for any arbitrary bumpy base comprising equally-sized spheres. It is shown in mono-disperse flows that as Ra increases, a transition occurs from slip (Ra 0.62 conditions. This work focuses on such a phase transition in bi-disperse flows, in which Ra can be a function of time. As size segregation takes place, large particles migrate away from the bottom, leading to a variation of size ratio between flow- and base-particles. As a result, base roughness Ra evolves with the progress of segregation. Consistent with the slip/non-slip transition in mono-disperse flows, basal sliding arises at low values of Ra and the development of segregation might be affected; when Ra increases to a certain level (Ra > 0.62, non-slip condition is respected. This work extends the validity of Ra to bi-disperse flows, which can be used to understand the geometric boundary effect during segregation.

Quantifying the Ebbinghaus figure effect: Target size, context size, and target-context distance determine the presence and direction of the illusion.

Directory of Open Access Journals (Sweden)

Hester eKnol

2015-11-01

Full Text Available Over the last 20 years, visual illusions, like the Ebbinghaus figure, have become widespread to investigate functional segregation of the visual system. This segregation reveals itself, so it is claimed, in the insensitivity of movement to optical illusions. This claim, however, faces contradictory results (and interpretations in the literature. These contradictions may be due to methodological weaknesses in, and differences across studies, some of which may hide a lack of perceptual illusion effects. Indeed, despite the long history of research with the Ebbinghaus figure, standardized configurations to predict the illusion effect are missing. Here, we present a complete geometrical description of the Ebbinghaus figure with three target sizes compatible with Fitts’ task. Each trial consisted of a stimulus and an isolated probe. The probe was controlled by the participant’s response through a staircase procedure. The participant was asked whether the probe or target appeared bigger. The factors target size, context size, target-context distance, and a control condition resulted in a 3×3×3+3 factorial design. The results indicate that the illusion magnitude, the perceptual distinctiveness, and the response time depend on the context size, distance, and especially, target size. In 33% of the factor combinations there was no illusion effect. The illusion magnitude ranged from zero to (exceptionally ten percent of the target size. The small (or absent illusion effects on perception and its possible influence on motor tasks might have been overlooked or misinterpreted in previous studies. Our results provide a basis for the application of the Ebbinghaus figure in psychophysical and motor control studies.

Uncertainties in effective dose estimates of adult CT head scans: The effect of head size

International Nuclear Information System (INIS)

Gregory, Kent J.; Bibbo, Giovanni; Pattison, John E.

2009-01-01

Purpose: This study is an extension of a previous study where the uncertainties in effective dose estimates from adult CT head scans were calculated using four CT effective dose estimation methods, three of which were computer programs (CT-EXPO, CTDOSIMETRY, and IMPACTDOSE) and one that involved the dose length product (DLP). However, that study did not include the uncertainty contribution due to variations in head sizes. Methods: The uncertainties due to head size variations were estimated by first using the computer program data to calculate doses to small and large heads. These doses were then compared with doses calculated for the phantom heads used by the computer programs. An uncertainty was then assigned based on the difference between the small and large head doses and the doses of the phantom heads. Results: The uncertainties due to head size variations alone were found to be between 4% and 26% depending on the method used and the patient gender. When these uncertainties were included with the results of the previous study, the overall uncertainties in effective dose estimates (stated at the 95% confidence interval) were 20%-31% (CT-EXPO), 15%-30% (CTDOSIMETRY), 20%-36% (IMPACTDOSE), and 31%-40% (DLP). Conclusions: For the computer programs, the lower overall uncertainties were still achieved when measured values of CT dose index were used rather than tabulated values. For DLP dose estimates, head size variations made the largest (for males) and second largest (for females) contributions to effective dose uncertainty. An improvement in the uncertainty of the DLP method dose estimates will be achieved if head size variation can be taken into account.

Uncertainties in effective dose estimates of adult CT head scans: The effect of head size

Energy Technology Data Exchange (ETDEWEB)

Gregory, Kent J.; Bibbo, Giovanni; Pattison, John E. [Department of Medical Physics, Royal Adelaide Hospital, Adelaide, South Australia 5000 (Australia) and School of Electrical and Information Engineering (Applied Physics), University of South Australia, Mawson Lakes, South Australia 5095 (Australia); Division of Medical Imaging, Women' s and Children' s Hospital, North Adelaide, South Australia 5006 (Australia) and School of Electrical and Information Engineering (Applied Physics), University of South Australia, Mawson Lakes, South Australia 5095 (Australia); School of Electrical and Information Engineering (Applied Physics), University of South Australia, Mawson Lakes, South Australia 5095 (Australia)

2009-09-15

Purpose: This study is an extension of a previous study where the uncertainties in effective dose estimates from adult CT head scans were calculated using four CT effective dose estimation methods, three of which were computer programs (CT-EXPO, CTDOSIMETRY, and IMPACTDOSE) and one that involved the dose length product (DLP). However, that study did not include the uncertainty contribution due to variations in head sizes. Methods: The uncertainties due to head size variations were estimated by first using the computer program data to calculate doses to small and large heads. These doses were then compared with doses calculated for the phantom heads used by the computer programs. An uncertainty was then assigned based on the difference between the small and large head doses and the doses of the phantom heads. Results: The uncertainties due to head size variations alone were found to be between 4% and 26% depending on the method used and the patient gender. When these uncertainties were included with the results of the previous study, the overall uncertainties in effective dose estimates (stated at the 95% confidence interval) were 20%-31% (CT-EXPO), 15%-30% (CTDOSIMETRY), 20%-36% (IMPACTDOSE), and 31%-40% (DLP). Conclusions: For the computer programs, the lower overall uncertainties were still achieved when measured values of CT dose index were used rather than tabulated values. For DLP dose estimates, head size variations made the largest (for males) and second largest (for females) contributions to effective dose uncertainty. An improvement in the uncertainty of the DLP method dose estimates will be achieved if head size variation can be taken into account.

Notch size effects on high cycle fatigue limit stress of Udimet 720

International Nuclear Information System (INIS)

Ren Weiju; Nicholas, Theodore

2003-01-01

Notch size effects on the high cycle fatigue (HCF) limit stress of Ni-base superalloy Udimet 720 were investigated on cylindrical specimens with three notch sizes of the same stress concentration factor K t =2.74. The HCF limit stress corresponding to a life of 10 6 cycles was experimentally determined at a stress ratio of 0.1 and a frequency of 25 Hz at room temperature. The stresses were calculated using finite element analysis (FEA) and the specimens analyzed using scanning electron microscopy (SEM). Test results show that at the same K t value, notch size can slightly affect the HCF limit stress of U720 when notch root plasticity occurs. FEA and SEM results reveal that the notch size effects are influenced by a complicated combination of the stress and plastic strain fields at the notch tip, the nominal stress, and the effects of prior plastic deformation on fatigue crack initiation

Accounting for One-Group Clustering in Effect-Size Estimation

Science.gov (United States)

Citkowicz, Martyna; Hedges, Larry V.

2013-01-01

In some instances, intentionally or not, study designs are such that there is clustering in one group but not in the other. This paper describes methods for computing effect size estimates and their variances when there is clustering in only one group and the analysis has not taken that clustering into account. The authors provide the effect size…

Contagion as Domino Effect in Global Stock Markets

NARCIS (Netherlands)

T.D. Markwat (Thijs); H.J.W.G. Kole (Erik); D.J.C. van Dijk (Dick)

2008-01-01

textabstractThis paper shows that stock market contagion operates through a domino effect, where small crashes evolve into more severe crashes. Using a novel unifying framework we model the occurrence of local, regional and global crashes in terms of past occurrences of these different crashes and

Size, Value, and Momentum in Polish Equity Returns: Local or International Factors?

Directory of Open Access Journals (Sweden)

Zaremba Adam

2017-09-01

Full Text Available This paper tests the performance of the Capital Asset Pricing Model (CAPM and the Fama-French three-factor and Carhart four-factor models on the Polish market. We use stock level data from April 2001 to January 2014 and find strong evidence for value and momentum effects, but only weak evidence for size premium. We formed portfolios double-sorted on size and book-to-market ratios, as well as on size and momentum, and we explain their returns with the above-mentioned asset pricing models. The CAPM is rejected and the three-factor and four-factor models perform well for the size and B/M sorted portfolios, but fail to explain returns on the size and momentum sorted portfolios. With the exception of the momentum factor, local Polish factors are not correlated with their European and global counterparts, suggesting market segmentation. Finally, the international value, size and momentum factors perform poorly in explaining cross-sectional variation in stock returns on the Polish market.

Experimentally simulated global warming and nitrogen enrichment effects on microbial litter decomposers in a marsh

DEFF Research Database (Denmark)

Flury, Sabine; Gessner, Mark

2011-01-01

obtained by denaturing gradient gel electrophoresis (DGGE) indicated that simulated global warming induced a shift in bacterial community structure. In addition, warming reduced fungal biomass, whereas bacterial biomass was unaffected. The mesh size of the litter bags and sampling date also had......Atmospheric warming and increased nitrogen deposition can lead to changes of microbial communities with possible consequences for biogeochemical processes. We used an enclosure facility in a freshwater marsh to assess the effects on microbes associated with decomposing plant litter under conditions...... of simulated climate warming and pulsed nitrogen supply. Standard batches of litter were placed in coarse-mesh and fine-mesh bags and submerged in a series of heated, nitrogen-enriched, and control enclosures. They were retrieved later and analyzed for a range of microbial parameters. Fingerprinting profiles...

Deformation modes and size effect in near-γ TiAl alloys

Energy Technology Data Exchange (ETDEWEB)

Monchoux, Jean-Philippe, E-mail: monchoux@cemes.fr; Luo, Jiangshan; Voisin, Thomas; Couret, Alain

2017-01-02

This paper presents a study of a size effect in TiAl alloys. Spark Plasma Sintering is used to sinter several alloys with a near-γ microstructure. Both the effect of boron as an inhibitor of grain growth and the rapidity of this powder metallurgy process are used to control the grain size. Following a comparison between EBSD-SEM (Electron Backscatter Diffraction by Scanning Electron Microscopy) and TEM (Transmission Electron Microscopy), the grain size is measured by TEM. Tensile tests are performed at room temperature to measure the yield stress. The deformation microstructure is studied by TEM. In a delimited area, activated deformation systems are identified in every grain. Then, for every system, the Schmid's factors as well as the defect nucleation sites are determined. A size effect leading to a high Hall-Petch constant of k=0.98 MPa m{sup 1/2} is measured. The deformation is found to be due to ordinary dislocations and twinning, which are mainly satisfying Schmid's law. Ordinary dislocations are more frequently observed than twins. Twins are found to form pile-ups and to cross the boundaries under the effect of stress concentration. These results are discussed and interpreted on the basis of the pile-up model applied to the Shockley dislocations involved in twinning.

Biofouling on buoyant marine plastics: An experimental study into the effect of size on surface longevity

International Nuclear Information System (INIS)

Fazey, Francesca M.C.; Ryan, Peter G.

2016-01-01

Recent estimates suggest that roughly 100 times more plastic litter enters the sea than is found floating at the sea surface, despite the buoyancy and durability of many plastic polymers. Biofouling by marine biota is one possible mechanism responsible for this discrepancy. Microplastics (<5 mm in diameter) are more scarce than larger size classes, which makes sense because fouling is a function of surface area whereas buoyancy is a function of volume; the smaller an object, the greater its relative surface area. We tested whether plastic items with high surface area to volume ratios sank more rapidly by submerging 15 different sizes of polyethylene samples in False Bay, South Africa, for 12 weeks to determine the time required for samples to sink. All samples became sufficiently fouled to sink within the study period, but small samples lost buoyancy much faster than larger ones. There was a direct relationship between sample volume (buoyancy) and the time to attain a 50% probability of sinking, which ranged from 17 to 66 days of exposure. Our results provide the first estimates of the longevity of different sizes of plastic debris at the ocean surface. Further research is required to determine how fouling rates differ on free floating debris in different regions and in different types of marine environments. Such estimates could be used to improve model predictions of the distribution and abundance of floating plastic debris globally. - Highlights: • We tested how fragment size affects the rate of buoyancy loss at sea due to biofouling for two low-density plastic polymers. • We found a strong direct relationship between fragment size and surface longevity. • Our longevity estimates ranged from 17 days for the thinnest microplastics to 66 days for thicker macroplastics. • Our results provide the first estimates of the longevity of different sizes of plastic debris at the ocean surface. • The results could be used to improve model predictions of the

Effects of Subscale Size and Shape on Global Energy Dissipation in a Multiscale Model of a Fiber-Reinforced Composite Exhibiting Post-Peak Strain Softening Using Abaqus and FEAMAC

Science.gov (United States)

Pineda, Evan, J.; Bednarcyk, Brett, A.; Arnold, Steven, M.

2012-01-01

A mesh objective crack band model is implemented in the generalized method of cells (GMC) micromechanics model to predict failure of a composite repeating unit cell (RUC). The micromechanics calculations are achieved using the MAC/GMC core engine within the ImMAC suite of micromechanics codes, developed at the NASA Glenn Research Center. The microscale RUC is linked to a macroscale Abaqus/Standard finite element model using the FEAMAC multiscale framework (included in the ImMAC suite). The effects of the relationship between the characteristic length of the finite element and the size of the microscale RUC on the total energy dissipation of the multiscale model are investigated. A simple 2-D composite square subjected to uniaxial tension is used to demonstrate the effects of scaling the dimensions of the RUC such that the length of the sides of the RUC are equal to the characteristic length of the finite element. These results are compared to simulations where the size of the RUC is fixed, independent of the element size. Simulations are carried out for a variety of mesh densities and element shapes, including square and triangular. Results indicate that a consistent size and shape must be used to yield preserve energy dissipation across the scales.

Effect of grain size on corrosion of nanocrystalline copper in NaOH solution

International Nuclear Information System (INIS)

Luo Wei; Xu Yimin; Wang Qiming; Shi Peizhen; Yan Mi

2010-01-01

Research highlights: → Coppers display an active-passive-transpassive behaviour with duplex passive film. → Grain size variation has little effect on the overall corrosion behaviour of Cu. → Little effect on corrosion may be due to duplex passivation in NaOH solution. → Bulk nanocrystalline Cu show bamboo-like flake corrosion structure. - Abstract: Effect of grain size on corrosion of bulk nanocrystalline copper was investigated using potentiodynamic polarization measurements in 0.1 M NaOH solution. Bulk nanocrystalline copper was prepared by inert gas condensation and in situ warm compress (IGCWC) method. The grain sizes of all bulk nanocrystalline samples were determined to be 48, 68 and 92 nm using X-ray diffraction (XRD). Results showed that bulk coppers displayed an active-passive-transpassive behaviour with duplex passive films. From polycrystalline to nanocrystalline, grain size variation showed little effect on the overall corrosion resistance of copper samples.

Global health promotion: how can we strengthen governance and build effective strategies?

Science.gov (United States)

Lee, Kelley

2006-12-01

This paper discusses what is meant by 'global health promotion' and the extent to which global governance architecture is emerging, enabling people to increase control over, and to improve, their health within an increasingly global context. A review of selected initiatives on breast-milk substitutes, healthy cities, tobacco control and diet and nutrition suggests that existing institutions are uneven in their capacity to tackle global health issues. The strategic building of a global approach to health promotion will draw on a broad range of governance instruments, give careful attention to implementation in the medium to longer term, reflect on the nature and appropriateness of partnerships and develop fuller understanding of effective policies for harnessing the positive influences of globalization and countering the negatives.

Size Effect on Acoustic Emission Characteristics of Coal-Rock Damage Evolution

OpenAIRE

Wen, Zhijie; Wang, Xiao; Chen, Lianjun; Lin, Guan; Zhang, Hualei

2017-01-01

Coal-gas outburst, rock burst, and other mine dynamic disasters are closely related to the instability and failure of coal-rock. Coal-rock is the assemblies of mineral particles of varying sizes and shapes bonded together by cementing materials. The damage and rupture process of coal-rock is accompanied by acoustic emission (AE), which can be used as an effective means to monitor and predict the instability of coal-rock body. In this manuscript, considering the size effect of coal-rock, the i...

Asymmetric Effects of Global Liquidity Expansion on Foreign Portfolio Inflows, Exchange Rates, and Stock Prices

Directory of Open Access Journals (Sweden)

Dong-Eun Rhee

2014-06-01

Full Text Available This paper examines the effects of global liquidity expansion on advanced and emerging economies by using panel VAR methodology. The results show that global liquidity expansion tends to boost economy by increasing GDP growth and stock prices. However, we find that the effects are asymmetric. The effects of global liquidity on GDP and stock prices are greater and more persistent in emerging economies than in liquidity recipient advanced economies. Moreover, global liquidity appreciates emerging economies' exchange rates more persistently than those of advanced economies. Lastly, while global liquidity expansion increases foreign portfolio investment inflows to Asian countries and liquidity recipient advanced economies, there is no evidence for Latin American countries.

Estimation of the global climate effect of brown carbon

Science.gov (United States)

Zhang, A.; Wang, Y.; Zhang, Y.; Weber, R. J.; Song, Y.

2017-12-01

Carbonaceous aerosols significantly affect global radiative forcing and climate through absorption and scattering of sunlight. Black carbon (BC) and brown carbon (BrC) are light-absorbing carbonaceous aerosols. The global distribution and climate effect of BrC is uncertain. A recent study suggests that BrC absorption is comparable to BC in the upper troposphere over biomass burning region and that the resulting heating tends to stabilize the atmosphere. Yet current climate models do not include proper treatments of BrC. In this study, we derived a BrC global biomass burning emission inventory from Global Fire Emissions Database 4 (GFED4) and developed a BrC module in the Community Atmosphere Model version 5 (CAM5) of Community Earth System Model (CESM) model. The model simulations compared well to BrC observations of the Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) and Deep Convective Clouds and Chemistry Project (DC-3) campaigns and includes BrC bleaching. Model results suggested that BrC in the upper troposphere due to convective transport is as important an absorber as BC globally. Upper tropospheric BrC radiative forcing is particularly significant over the tropics, affecting the atmosphere stability and Hadley circulation.

An Introductory Summary of Various Effect Size Choices.

Science.gov (United States)

Cromwell, Susan

This paper provides a tutorial summary of some of the many effect size choices so that members of the Southwest Educational Research Association would be better able to follow the recommendations of the American Psychological Association (APA) publication manual, the APA Task Force on Statistical Inference, and the publication requirements of some…

Contrast enhancement of focal hepatic lesions in CT: effect of size and histology

International Nuclear Information System (INIS)

Burgener, F.A.; Hamlin, D.J.

1983-01-01

The effect of size and histology on the contrast enhancement of hepatic lesions has been analyzed in this clinical and experimental investigation yielding the following results: (1) The attenuation values of hepatic cysts in patients increase significantly and inversely with their size after contrast enhancement when the cysts measure less than twice the CT-slice thickness. This seems to be caused by partial-volume effect. (2) Experimental tumors of identical sizes and originating from the same cell line can demonstrate different contrast-enhancement patterns. (3) Peak contrast uptake in both experimental and human tumors seems to be inversely related to their size. (4) Compared to liver, contrast washout from experimental and human tumors (presumably the extravascular space) is delayed. The delay in the contrast washout from a tumor seems to correlate with tumor size. These findings suggest that in general, it is not possible to differentiate reliably among various hepatic neoplasms on the basis of their contrast enhancement patterns for the following reasons: (1) Attenuation values of small hepatic neoplasms are distorted by partial volume effect. (2) Tumors of different histologies can demonstrate the same enhancement pattern. (3) Tumors of identical histology and size can demonstrate different enhancement patterns. (4) The enhancement pattern of a tumor changes with growth or size

Effects of aerosol from biomass burning on the global radiation budget

Science.gov (United States)

Penner, Joyce E.; Dickinson, Robert E.; O'Neill, Christine A.

1992-01-01

An analysis is made of the likely contribution of smoke particles from biomass burning to the global radiation balance. These particles act to reflect solar radiation directly; they also can act as cloud condensation nuclei, increasing the reflectivity of clouds. Together these effects, although uncertain, may add up globally to a cooling effect as large as 2 watts per square meter, comparable to the estimated contribution to sulfate aerosols. Anthropogenic increases of smoke emission thus may have helped weaken the net greenhouse warming from anthropogenic trace gases.

EFFECT OF FARM SIZE AND FREQUENCY OF CUTTING ON ...

African Journals Online (AJOL)

EFFECT OF FARM SIZE AND FREQUENCY OF CUTTING ON OUTPUT OF ... the use of Ordinary Least Square (OLS) estimation technique was used in analyzing ... frequency of cutting that would produce maximum output of the vegetable as ...

Distinguishing crystallite size effects from those of structural disorder ...

Indian Academy of Sciences (India)

Administrator

Both crystallite size effects and structural disorder contribute to the broadening of lines in .... ple contributions to the peak profiles. ... the fit is then corrected by accounting for sample ... Authors thank the Department of Science and Tech-.

Coupling of magnetospheric electrical effects into the global atmospheric electrical circuit

International Nuclear Information System (INIS)

Hays, P.B.; Roble, R.G.

1979-01-01

A quasi-static model of global atmospheric electricity has been constructed (Hays and Roble, 1978) to study the electrical processes in the lower atmosphere and the coupling between solar- and upper- atmosphere-induced variations superimposed upon the global electrical circuit. The paper reviews the essential features of this model and discusses the results obtained thus far on the effects of magnetospheric convection and substorms on the global atmospheric electrical circuit. A schematic diagram of the global quasi-static model is given. It is assumed that thunderstorms act as dipole generators, each with a positive center at the top of the cloud and a negative center a few kilometers lower than the positive center

Ultrasonic velocimetry studies on different salts of chitosan: Effect of ion size.

Science.gov (United States)

Mohan, C Raja; Sathya, R; Nithiananthi, P; Jayakumar, K

2017-11-01

In the present investigation, the effect of ion size on the thermodynamical properties such as ultrasonic velocity (U), adiabatic compressibility (β), acoustic impedance (Z), adiabatic bulk modulus (K s ), relaxation strength (r s ) have been obtained for the different salts of chitosan viz., formate (3.5Å), acetate (4.5Å), Succinate (5Å) and Adipate (6Å). To find the effect of ion size, the effect due to water has been removed by calculating the change in ultrasonic velocity (dU), change in adiabatic compressibility (dβ), in acoustic impedance (dZ), in adiabatic bulk modulus (dK s ), and in relaxation strength (dr s ). Space filling factor and polarizability has been obtained from the refractive index data through Lorentz-Lorentz relation. FTIR studies confirm the formation of different quaternary salts of chitosan and their size (mass) effects which has been verified with Hooke's law. All the said properties vary both with ion size and concentration of different salts of chitosan. This investigation may throw some light on better usage of chitosan in biomedical applications. The detailed results are presented and discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Hierarchical structure observation and nanoindentation size effect characterization for a limnetic shell

Science.gov (United States)

Song, Jingru; Fan, Cuncai; Ma, Hansong; Wei, Yueguang

2015-06-01

In the present research, hierarchical structure observation and mechanical property characterization for a type of biomaterial are carried out. The investigated biomaterial is Hyriopsis cumingii, a typical limnetic shell, which consists of two different structural layers, a prismatic "pillar" structure and a nacreous "brick and mortar" structure. The prismatic layer looks like a "pillar forest" with variation-section pillars sized on the order of several tens of microns. The nacreous material looks like a "brick wall" with bricks sized on the order of several microns. Both pillars and bricks are composed of nanoparticles. The mechanical properties of the hierarchical biomaterial are measured by using the nanoindentation test. Hardness and modulus are measured for both the nacre layer and the prismatic layer, respectively. The nanoindentation size effects for the hierarchical structural materials are investigated experimentally. The results show that the prismatic nanostructured material has a higher stiffness and hardness than the nacre nanostructured material. In addition, the nanoindentation size effects for the hierarchical structural materials are described theoretically, by using the trans-scale mechanics theory considering both strain gradient effect and the surface/interface effect. The modeling results are consistent with experimental ones.

The cretaceous/tertiary-boundary impact and its global effects with reference to Australia

International Nuclear Information System (INIS)

Sutherland, F.L.

1996-01-01

Considerable evidence exists for a major meteoritic impact at Chicxulub, Mexico, and its effects at the Cretaceous/Tertiary boundary (KTB). It includes a buried crater, subglobal ejecta, and global fireball deposits that incorporate shocked minerals and non-terrestrial spinels. Platinum-group-element enrichments (Ir anomaly) and marked C- and O-isotope shifts at the KTB coincide with an extinction event. Australia contributes little to the KTB impact story as far, but was isolated from the severest impact and extinction effects. A Chicxulub strike (C- or L-chondrite impactor) explains many KTB features, but does not satisfy all KTB studies. Continuing KTB impact debates include the size of Chicxulub crater, the extent of heterogeneous spinels. The role of KTB plume volcanism (whether impact-induced or not) and the nature of KTB extinctions (whether caused by climatic cooling or warming and whether sharp, gradual or latitudinally reduced) are also in debate. This synthesis suggests that the Chicxulub impact produced a crater 180 km wide and possibly induced tsunamigenic activity; that compositional differences between impact deposits might reflect more that one impact coinciding with the KTB; that the Deccan volcanism predates the KTB in India; and that several KTB studies tentatively suggest maximum impact and subordinate volcanic effects within lower latitudes. 98 refs., 4 figs

Influence of grain size on the extraordinary Hall effect in magnetic granular alloys

International Nuclear Information System (INIS)

Granovsky, Alexander B.; Kalitsov, Alan V.; Khanikaev, Alexander B.; Kioussis, Nicholas

2003-01-01

A quantum statistical theory of the influence of grain size on the residual extraordinary Hall effect (EHE) in magnetic metal-insulator granular alloys is presented. It is shown that under certain conditions the quasi-classical size-effect (QSE) can lead to similar behaviors of EHE in metal-metal and metal-insulator alloys. The possible dependences of EHE coefficient on the grain size and the role of the QSE in the giant EHE in nanocomposites are discussed

Influence of grain size on the extraordinary Hall effect in magnetic granular alloys

Energy Technology Data Exchange (ETDEWEB)

Granovsky, Alexander B. E-mail: granov@magn.ru; Kalitsov, Alan V.; Khanikaev, Alexander B.; Kioussis, Nicholas

2003-03-01

A quantum statistical theory of the influence of grain size on the residual extraordinary Hall effect (EHE) in magnetic metal-insulator granular alloys is presented. It is shown that under certain conditions the quasi-classical size-effect (QSE) can lead to similar behaviors of EHE in metal-metal and metal-insulator alloys. The possible dependences of EHE coefficient on the grain size and the role of the QSE in the giant EHE in nanocomposites are discussed.

Effect Size Analyses of Souvenaid in Patients with Alzheimer’s Disease

Science.gov (United States)

Cummings, Jeffrey; Scheltens, Philip; McKeith, Ian; Blesa, Rafael; Harrison, John E.; Bertolucci, Paulo H.F.; Rockwood, Kenneth; Wilkinson, David; Wijker, Wouter; Bennett, David A.; Shah, Raj C.

2016-01-01

Background: Souvenaid® (uridine monophosphate, docosahexaenoic acid, eicosapentaenoic acid, choline, phospholipids, folic acid, vitamins B12, B6, C, and E, and selenium), was developed to support the formation and function of neuronal membranes. Objective: To determine effect sizes observed in clinical trials of Souvenaid and to calculate the number needed to treat to show benefit or harm. Methods: Data from all three reported randomized controlled trials of Souvenaid in Alzheimer’s disease (AD) dementia (Souvenir I, Souvenir II, and S-Connect) and an open-label extension study were included in analyses of effect size for cognitive, functional, and behavioral outcomes. Effect size was determined by calculating Cohen’s d statistic (or Cramér’s V method for nominal data), number needed to treat and number needed to harm. Statistical calculations were performed for the intent-to-treat populations. Results: In patients with mild AD, effect sizes were 0.21 (95% confidence intervals: –0.06, 0.49) for the primary outcome in Souvenir II (neuropsychological test battery memory z-score) and 0.20 (0.10, 0.34) for the co-primary outcome of Souvenir I (Wechsler memory scale delayed recall). No effect was shown on cognition in patients with mild-to-moderate AD (S-Connect). The number needed to treat (6 and 21 for Souvenir I and II, respectively) and high number needed to harm values indicate a favorable harm:benefit ratio for Souvenaid versus control in patients with mild AD. Conclusions: The favorable safety profile and impact on outcome measures converge to corroborate the putative mode of action and demonstrate that Souvenaid can achieve clinically detectable effects in patients with early AD. PMID:27767993

Effect of colour and relative product size (RPS) on consumer attitudes

OpenAIRE

Varsha Jain; Subhadip Roy; Adwita Pant

2013-01-01

Colour and visuals are used extensively by the advertisers of different product categories to attract consumer attention and create favourable attitude. Based on this premise, the present study aimed to explore the effect of colour and relative product size on the consumer attitudes incorporating the moderating role of product familiarity. An experimental design was used, with a sample size of 420 respondents of 18-25 years in a 3 (Product Size: Large/Med/Small) X 2 (Ad Colour: CL/BW) X 2 (Ge...

The Dependence of Tropical Cyclone Count and Size on Rotation Rate

Science.gov (United States)

Chavas, D. R.; Reed, K. A.

2017-12-01

Both theory and idealized equilibrium modeling studies indicate that tropical cyclone size decreases with background rotation rate. In contrast, in real-world observations size tends to increase with latitude. Here we seek to resolve this apparent contradiction via a set of reduced-complexity global aquaplanet simulations with varying planetary rotation rates using the NCAR Community Atmosphere Model 5. The latitudinal distribution of both storm count and size are found to vary markedly with rotation rate, yielding insight into the dynamical constraints on tropical cyclone activity on a rotating planet. Moreover, storm size is found to vary non-monotonically with latitude, indicating that non-equilibrium effects are crucial to the life-cycle evolution of size in nature. Results are then compared to experiments in idealized, time-dependent limited-area modeling simulations using CM1 in axisymmetric and three-dimensional geometry. Taken together, this hierarchy of models is used to quantify the role of equilibrium versus transient controls on storm size and the relevance of each to real storms in nature.

Excitonic effects and related properties in semiconductor nanostructures: roles of size and dimensionality

Science.gov (United States)

Wu, Shudong; Cheng, Liwen; Wang, Qiang

2017-08-01

The size- and dimensionality-dependence of excitonic effects and related properties in semiconductor nanostructures are theoretically studied in detail within the effective-mass approximation. When nanostructure sizes become smaller than the bulk exciton Bohr radius, excitonic effects are significantly enhanced with reducing size or dimensionality. This is as a result of quantum confinement in more directions leading to larger exciton binding energies and normalized exciton oscillator strengths. These excitonic effects originate from electron-hole Coulombic interactions, which strongly enhance the oscillator strength between the electron and hole. It is also established that the universal scaling of exciton binding energy versus the inverse of the exciton Bohr radius follows a linear scaling law. Herein, we propose a stretched exponential law for the size scaling of optical gap, which is in good agreement with the calculated data. Due to differences in the confinement dimensionality, the radiative lifetime of low-dimensional excitons becomes shorter than that of bulk excitons. The size dependence of the exciton radiative lifetimes is in good agreement with available experimental data. This strongly enhanced electron-hole exchange interaction is expected in low-dimensional structures due to enriched excitonic effects. The main difference in nanostructures compared to the bulk can be interpreted in terms of the enhanced excitonic effects induced by exciton localization. The enhanced excitonic effects are expected to be of importance in developing stable and high-efficiency nanoscale excitonic optoelectronic devices.

The effect of reducing alfalfa haylage particle size on cows in early lactation.

Science.gov (United States)

Kononoff, P J; Heinrichs, A J

2003-04-01

The objective of this experiment was to evaluate effects of reducing forage particle size on cows in early lactation based on measurements of the Penn State Particle Separator (PSPS). Eight cannulated, multiparous cows averaging 19 +/- 4 d in milk and 642 +/- 45 kg BW were assigned to one of two 4 x 4 Latin Squares. During each of the 23-d periods, animals were offered one of four diets, which were chemically identical but included alfalfa haylage of different particle size; short (SH), mostly short (MSH), mostly long (MLG), and long (LG). Physically effective neutral detergent fiber (peNDF) was determined by measuring the amount of neutral detergent fiber retained on a 1.18 mm screen and was similar across diets (25.7, 26.2, 26.4, 26.7%) but the amount of particles >19.0 mm significantly decreased with decreasing particle size. Reducing haylage particle size increased dry matter intake linearly (23.3, 22.0, 20.9, 20.8 kg for SH, MSH, MLG, LG, respectively). Milk production and percentage fat did not differ across treatments averaging 35.5 +/- 0.68 kg milk and 3.32 +/- 0.67% fat, while a quadratic effect was observed for percent milk protein, with lowest values being observed for LG. A quadratic effect was observed for mean rumen pH (6.04, 6.15, 6.13, 6.09), while A:P ratio decreased linearly (2.75, 2.86, 2.88, 2.92) with decreasing particle size. Total time ruminating increased quadratically (467, 498, 486, 468 min/d), while time eating decreased linearly (262, 253, 298, 287 min/d) with decreasing particle size. Both eating and ruminating per unit of neutral detergent fiber intake decreased with reducing particle size (35.8, 36.7, 44.9, 45.6 min/kg; 19.9, 23.6, 23.5, 23.5 min/kg). Although chewing activity was closely related to forage particle size, effects on rumen pH were small, indicating factors other than particle size are critical in regulating pH when ration neutral detergent fiber met recommended levels. Feeding alfalfa haylage based rations of reduced

Effects of foliage clumping on the estimation of global terrestrial gross primary productivity

Science.gov (United States)

Chen, Jing M.; Mo, Gang; Pisek, Jan; Liu, Jane; Deng, Feng; Ishizawa, Misa; Chan, Douglas

2012-03-01

Sunlit and shaded leaf separation proposed by Norman (1982) is an effective way to upscale from leaf to canopy in modeling vegetation photosynthesis. The Boreal Ecosystem Productivity Simulator (BEPS) makes use of this methodology, and has been shown to be reliable in modeling the gross primary productivity (GPP) derived from CO2flux and tree ring measurements. In this study, we use BEPS to investigate the effect of canopy architecture on the global distribution of GPP. For this purpose, we use not only leaf area index (LAI) but also the first ever global map of the foliage clumping index derived from the multiangle satellite sensor POLDER at 6 km resolution. The clumping index, which characterizes the degree of the deviation of 3-dimensional leaf spatial distributions from the random case, is used to separate sunlit and shaded LAI values for a given LAI. Our model results show that global GPP in 2003 was 132 ± 22 Pg C. Relative to this baseline case, our results also show: (1) global GPP is overestimated by 12% when accurate LAI is available but clumping is ignored, and (2) global GPP is underestimated by 9% when the effective LAI is available and clumping is ignored. The clumping effects in both cases are statistically significant (p < 0.001). The effective LAI is often derived from remote sensing by inverting the measured canopy gap fraction to LAI without considering the clumping. Global GPP would therefore be generally underestimated when remotely sensed LAI (actually effective LAI by our definition) is used. This is due to the underestimation of the shaded LAI and therefore the contribution of shaded leaves to GPP. We found that shaded leaves contribute 50%, 38%, 37%, 39%, 26%, 29% and 21% to the total GPP for broadleaf evergreen forest, broadleaf deciduous forest, evergreen conifer forest, deciduous conifer forest, shrub, C4 vegetation, and other vegetation, respectively. The global average of this ratio is 35%.

On the origin of the cobalt particle size effects in Fischer−Tropsch catalysis

NARCIS (Netherlands)

den Breejen, J.P.|info:eu-repo/dai/nl/304837318; Radstake, P.B.|info:eu-repo/dai/nl/304829587; Bezemer, G.L.; Bitter, J.H.|info:eu-repo/dai/nl/160581435; Froseth, V.; Holmen, A.; de Jong, K.P.|info:eu-repo/dai/nl/06885580X

2009-01-01

The effects of metal particle size in catalysis are of prime scientific and industrial importance and call for a better understanding. In this paper the origin of the cobalt particle size effects in Fischer−Tropsch (FT) catalysis was studied. Steady-State Isotopic Transient Kinetic Analysis (SSITKA)

The effect of laser unit on photodynamic therapy spot size.

Science.gov (United States)

Ansari-Shahrezaei, Siamak; Binder, Susanne; Stur, Michael

2011-01-01

To determine the effect of the laser unit on photodynamic therapy (PDT) spot size. A calibrated Gullstrand-type model eye was used for this study. The axial length of the model eye was set to different values ranging from 22.2 to 27.0 mm, and the actual spot size from the laser console was recorded for treating a spot of 4 mm in the center of the artificial fundus using two different laser units (Coherent Opal laser; Coherent Inc, Santa Clara, California, USA and Zeiss Visulas laser; Carl Zeiss Meditec Inc, Dublin, California, USA) and two indirect contact laser lenses (Volk PDT laser lens and Volk Area Centralis lens; Volk Optical Inc, Mentor, Ohio, USA). From myopia to hyperopia, the total deviation from the intended spot size was -22.5% to -7.5% (Opal laser and PDT laser lens), and -17.5% to +2.5% (Visulas laser and PDT laser lens), -12.5% to +7.5% (Opal laser and Area Centralis lens), and -7.5% to +10% (Visulas laser and Area Centralis lens). The used laser unit has a significant effect on PDT spot size in this model. These findings may be important for optimizing PDT of choroidal neovascular lesions.

Globalization

OpenAIRE

Tulio Rosembuj

2006-01-01

There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

The global alcohol industry: an overview.

Science.gov (United States)

Jernigan, David H

2009-02-01

To describe the globalized sector of the alcoholic beverage industry, including its size, principal actors and activities. Market research firms and business journalism are the primary sources for information about the global alcohol industry, and are used to profile the size and membership of the three main industry sectors of beer, distilled spirits and wine. Branded alcoholic beverages are approximately 38% of recorded alcohol consumption world-wide. Producers of these beverages tend to be large multi-national corporations reliant on marketing for their survival. Marketing activities include traditional advertising as well as numerous other activities, such as new product development, product placement and the creation and promotion of social responsibility programs, messages and organizations. The global alcohol industry is highly concentrated and innovative. There is relatively little public health research evaluating the impact of its many marketing activities.

Global precedence effects account for individual differences in both face and object recognition performance

DEFF Research Database (Denmark)

Gerlach, Christian; Starrfelt, Randi

2018-01-01

examine whether global precedence effects, measured by means of non-face stimuli in Navon's paradigm, can also account for individual differences in face recognition and, if so, whether the effect is of similar magnitude for faces and objects. We find evidence that global precedence effects facilitate...... both face and object recognition, and to a similar extent. Our results suggest that both face and object recognition are characterized by a coarse-to-fine temporal dynamic, where global shape information is derived prior to local shape information, and that the efficiency of face and object recognition...

Thermal and particle size distribution effects on the ferromagnetic resonance in magnetic fluids

International Nuclear Information System (INIS)

Marin, C.N.

2006-01-01

Thermal and particle size distribution effects on the ferromagnetic resonance of magnetic fluids were theoretically investigated, assuming negligible interparticle interactions and neglecting the viscosity of the carrier liquid. The model is based on the usual approach for the ferromagnetic resonance description of single-domain magnetic particle systems, which was amended in order to take into account the finite particle size effect, the particle size distribution and the orientation mobility of the particles within the magnetic fluid. Under these circumstances the shape of the resonance line, the resonance field and the line width are found to be strongly affected by the temperature and by the particle size distribution of magnetic fluids

Adaptive evolution of body size subject to indirect effect in trophic cascade system.

Science.gov (United States)

Wang, Xin; Fan, Meng; Hao, Lina

2017-09-01

Trophic cascades represent a classic example of indirect effect and are wide-spread in nature. Their ecological impact are well established, but the evolutionary consequences have received even less theoretical attention. We theoretically and numerically investigate the trait (i.e., body size of consumer) evolution in response to indirect effect in a trophic cascade system. By applying the quantitative trait evolutionary theory and the adaptive dynamic theory, we formulate and explore two different types of eco-evolutionary resource-consumer-predator trophic cascade model. First, an eco-evolutionary model incorporating the rapid evolution is formulated to investigate the effect of rapid evolution of the consumer's body size, and to explore the impact of density-mediate indirect effect on the population dynamics and trait dynamics. Next, by employing the adaptive dynamic theory, a long-term evolutionary model of consumer body size is formulated to evaluate the effect of long-term evolution on the population dynamics and the effect of trait-mediate indirect effect. Those models admit rich dynamics that has not been observed yet in empirical studies. It is found that, both in the trait-mediated and density-mediated system, the body size of consumer in predator-consumer-resource interaction (indirect effect) evolves smaller than that in consumer-resource and predator-consumer interaction (direct effect). Moreover, in the density-mediated system, we found that the evolution of consumer body size contributes to avoiding consumer extinction (i.e., evolutionary rescue). The trait-mediate and density-mediate effects may produce opposite evolutionary response. This study suggests that the trophic cascade indirect effect affects consumer evolution, highlights a more comprehensive mechanistic understanding of the intricate interplay between ecological and evolutionary force. The modeling approaches provide avenue for study on indirect effects from an evolutionary perspective

A closer look at the size of the gaze-liking effect: a preregistered replication.

Science.gov (United States)

Tipples, Jason; Pecchinenda, Anna

2018-04-30

This study is a direct replication of gaze-liking effect using the same design, stimuli and procedure. The gaze-liking effect describes the tendency for people to rate objects as more likeable when they have recently seen a person repeatedly gaze toward rather than away from the object. However, as subsequent studies show considerable variability in the size of this effect, we sampled a larger number of participants (N = 98) than the original study (N = 24) to gain a more precise estimate of the gaze-liking effect size. Our results indicate a much smaller standardised effect size (d z  = 0.02) than that of the original study (d z  = 0.94). Our smaller effect size was not due to general insensitivity to eye-gaze effects because the same sample showed a clear (d z  = 1.09) gaze-cuing effect - faster reaction times when eyes looked toward vs away from target objects. We discuss the implications of our findings for future studies wishing to study the gaze-liking effect.

The effects of globalization on firm’s stock in the selected Asian countries

Directory of Open Access Journals (Sweden)

Sepideh Haghi

2015-06-01

Full Text Available This study aims to survey the effects of economic globalization on the firm’s stock that is measured by the index of the stock market by using panel data in selected countries in Asia (Iran, Saudi Arabia, India, China, Singapore, Malaysia, Indonesia, South Korea, Russia, Pakistan, Philippines, Sri Lanka during 1997- 2013. Unit root tests indicate that the variables are stationary on the level. The results of F-test, Breusch-Pagan and Hausman tests show that the unilateral fixed effects must be applied. The results show that the economic globalization significantly improves stock market index. Moreover the positive and significant effect on the firm’s stock depend on political globalization and dummy variable, however the negative and significant effect is related to the growth rate of government expenditure, the exchange rate and the interaction effects of economy.

IMPACT OF GLOBALIZATION ON THE PERFORMANCE OF THE COMPANY: THE CASE OF COMPANIES FROM BOSNIA AND HERZEGOVINA

Directory of Open Access Journals (Sweden)

Hasan Mahmutović

2017-04-01

Full Text Available The discourse of globalization and its effects have been the most current topic in the field of economics in recent times. However, empirical research on the impact of globalization on companies, especially in transition countries, is very scarce. This paper focuses on the study of the impact of globalization on the performance of companies in Bosnia and Herzegovina by analyzing their interrelationships. The findings, in the case of companies in Bosnia and Herzegovina, have confirmed earlier findings about the double impact of globalization by showing, on the one hand, its positive effects and, on the other hand, the negative effects on the performance of the companies. Additionally, the research results have shown that negative effects are felt more strongly in the case of small and medium-sized companies than in the case of large companies.

Size-effect features on the magnetothermopower of bismuth nanowires

International Nuclear Information System (INIS)

Condrea, E.; Nicorici, A.

2011-01-01

Full text: In this work we have studied the magnetic field dependence of the thermopower (TEP) and resistance of glass-coated Bi wires with diameter (d) from 100 nm to at 1.5 μm below 80 K. Nanowires have anomalously large values of the thermopower (+100 μV K.1) and relatively high effective resistivities, but their frequencies of SdH oscillations remain those of bulk Bi. The TEP stays positive in longitudinal magnetic fields up to 15 T, where the surface scattering of charge carriers is negligible. Our analysis shows that the anomalous thermopower has a diffusion origin and is a consequence of the microstructure rather than the result of the strong scattering of electrons by the wire walls. The intensities of field at which the size-effect features appear on the magnetothermopower curves correspond to a value at which the diameter of the hole cyclotron orbit equals d. Size-effect features were observed only for set of nanowires with d = 100-350 nm, where diffusion TEP is dominant. The contribution of the phonon-drag effect was observed in a wire with diameter larger than 400 nm and becomes dominant at diameter of 1 μm. (authors)

Size-dependent nonlocal effects in plasmonic semiconductor particles

DEFF Research Database (Denmark)

Maack, Johan Rosenkrantz; Mortensen, N. Asger; Wubs, Martijn

2017-01-01

Localized surface plasmons (LSP) in semiconductor particles are expected to exhibit spatial nonlocal response effects as the geometry enters the nanometer scale. To investigate these nonlocal effects, we apply the hydrodynamic model to nanospheres of two different semiconductor materials: intrinsic...... InSb and n-doped GaAs. Our results show that the semiconductors indeed display nonlocal effects, and that these effects are even more pronounced than in metals. In a 150 nm InSb particle at 300 K, the LSP frequency is blueshifted 35%, which is orders of magnitude larger than the blueshift in a metal...... particle of the same size. This property, together with their tunability, makes semiconductors a promising platform for experiments in nonlocal effects. Copyright (C)EPLA, 2017...

Finite-size effects for anisotropic bootstrap percolation : Logarithmic corrections

NARCIS (Netherlands)

van Enter, Aernout C. D.; Hulshof, Tim

In this note we analyse an anisotropic, two-dimensional bootstrap percolation model introduced by Gravner and Griffeath. We present upper and lower bounds on the finite-size effects. We discuss the similarities with the semi-oriented model introduced by Duarte.

Finite-size effects for anisotropic bootstrap percolation: logerithmic corrections

NARCIS (Netherlands)

Enter, van A.C.D.; Hulshof, T.

2007-01-01

In this note we analyse an anisotropic, two-dimensional bootstrap percolation model introduced by Gravner and Griffeath. We present upper and lower bounds on the finite-size effects. We discuss the similarities with the semi-oriented model introduced by Duarte.

Time-varying correlations in global real estate markets: A multivariate GARCH with spatial effects approach

Science.gov (United States)

Gu, Huaying; Liu, Zhixue; Weng, Yingliang

2017-04-01

The present study applies the multivariate generalized autoregressive conditional heteroscedasticity (MGARCH) with spatial effects approach for the analysis of the time-varying conditional correlations and contagion effects among global real estate markets. A distinguishing feature of the proposed model is that it can simultaneously capture the spatial interactions and the dynamic conditional correlations compared with the traditional MGARCH models. Results reveal that the estimated dynamic conditional correlations have exhibited significant increases during the global financial crisis from 2007 to 2009, thereby suggesting contagion effects among global real estate markets. The analysis further indicates that the returns of the regional real estate markets that are in close geographic and economic proximities exhibit strong co-movement. In addition, evidence of significantly positive leverage effects in global real estate markets is also determined. The findings have significant implications on global portfolio diversification opportunities and risk management practices.

Communication: Nucleation of water on ice nanograins: Size, charge, and quantum effects

Energy Technology Data Exchange (ETDEWEB)

Marciante, Mathieu [Institut Lumière Matière, UMR5306 Université Lyon 1 – CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); Calvo, Florent, E-mail: florent.calvo@ujf-grenoble.fr [Institut Lumière Matière, UMR5306 Université Lyon 1 – CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); Laboratoire Interdisciplinaire de Physique, Rue de La Piscine, Campus Saint Martin d’Hères, 38000 Grenoble (France)

2015-05-07

The sticking cross sections of water molecules on cold size-selected water clusters have been simulated using classical and quantum (path-integral) molecular dynamics trajectories under realistic conditions. The integrated cross sections for charged clusters show significant size effects with comparable trends as in experiments, as well as essentially no sign effect. Vibrational delocalization, although it contributes to enlarging the geometric cross sections, leads to a counter-intuitive decrease in the dynamical cross section obtained from the trajectories. These results are interpreted based on the apparent reduction in the effective interaction between the projectile and the target owing to zero-point effects.

Communication: Nucleation of water on ice nanograins: Size, charge, and quantum effects

International Nuclear Information System (INIS)

Marciante, Mathieu; Calvo, Florent

2015-01-01

The sticking cross sections of water molecules on cold size-selected water clusters have been simulated using classical and quantum (path-integral) molecular dynamics trajectories under realistic conditions. The integrated cross sections for charged clusters show significant size effects with comparable trends as in experiments, as well as essentially no sign effect. Vibrational delocalization, although it contributes to enlarging the geometric cross sections, leads to a counter-intuitive decrease in the dynamical cross section obtained from the trajectories. These results are interpreted based on the apparent reduction in the effective interaction between the projectile and the target owing to zero-point effects

Material inertia and size effects in the Charpy V-notch test

DEFF Research Database (Denmark)

Desandre, D. A.; Benzerga, A. A.; Tvergaard, Viggo

2004-01-01

The effect of material inertia on the size dependence of the absorbed energy in the Charpy V-notch test is investigated. The material response is characterized by an elastic-viscoplastic constitutive relation for a porous plastic solid, with adiabatic heating due to plastic dissipation and the re......The effect of material inertia on the size dependence of the absorbed energy in the Charpy V-notch test is investigated. The material response is characterized by an elastic-viscoplastic constitutive relation for a porous plastic solid, with adiabatic heating due to plastic dissipation...

A Basketball Court-Size Global Map of Mars for Education and Public Outreach

Science.gov (United States)

Hill, J. R.; Christensen, P. R.

2017-12-01

The Thermal Emission Imaging System (THEMIS) onboard the 2001 Mars Odyssey spacecraft has acquired over 220,000 infrared images of the Martian surface at a resolution of 100 m/pixel since the start of science operations in February 2002. A global map was previously developed by mosaicking together over 24,000 high-quality full-resolution THEMIS daytime infrared images. Although the resulting map has been extremely valuable for scientific and mission operations applications, it has been difficult to communicate this value to students, citizen scientists and the general public, since their interactions with the map have been limited to computer-based geographic information system (GIS) interfaces. We determined that, in order to better communicate the value and importance of mapping the entire Martian surface at this resolution, people need to be able to physically interact with the map and experience its full scale. Therefore, the THEMIS Day IR Global Mosaic with Colorized MOLA Elevation will be printed on a 45ft x 90ft vinyl mat, which will allow observers to walk across and physically experience the map at approximately full resolution (printed at 200 pixels per inch). The size of the map was chosen to fit on a standard high school basketball court, so that a large number of schools will have a sufficiently large indoor surface on which to display the map for education events. The vinyl material and printing process selected for the map have been proven to be wear-resistant in similar applications, as long as everyone who walks on the map wears socks or similarly soft foot coverings. In order to make transportation easier, the map will be printed in two 45ft x 45ft sections, which will be joined together at events to create the full 45ft x 90ft map. The final stages of the map production will take place in early fall 2017, followed by initial education events at Arizona State University and local schools to test the educational activities associated with the map

Effect of laser spot size on energy balance in laser induced plasmas

International Nuclear Information System (INIS)

Pant, H.C.; Sharma, S.; Bhawalkar, D.D.

1980-01-01

The effect of the laser spot size on laser light absorption in laser induced plasmas from solid targets was studied. It was found that at a constant laser intensity on the target, reduction in the laser spot size enhances the net laser energy absorption. It was also observed that the laser light reflection from the target becomes more diffused when the focal spot size is reduced

Balancing the dilution and oddity effects: decisions depend on body size.

Directory of Open Access Journals (Sweden)

Gwendolen M Rodgers

Full Text Available Grouping behaviour, common across the animal kingdom, is known to reduce an individual's risk of predation; particularly through dilution of individual risk and predator confusion (predator inability to single out an individual for attack. Theory predicts greater risk of predation to individuals more conspicuous to predators by difference in appearance from the group (the 'oddity' effect. Thus, animals should choose group mates close in appearance to themselves (eg. similar size, whilst also choosing a large group.We used the Trinidadian guppy (Poecilia reticulata, a well known model species of group-living freshwater fish, in a series of binary choice trials investigating the outcome of conflict between preferences for large and phenotypically matched groups along a predation risk gradient. We found body-size dependent differences in the resultant social decisions. Large fish preferred shoaling with size-matched individuals, while small fish demonstrated no preference. There was a trend towards reduced preferences for the matched shoal under increased predation risk. Small fish were more active than large fish, moving between shoals more frequently. Activity levels increased as predation risk decreased. We found no effect of unmatched shoal size on preferences or activity.Our results suggest that predation risk and individual body size act together to influence shoaling decisions. Oddity was more important for large than small fish, reducing in importance at higher predation risks. Dilution was potentially of limited importance at these shoal sizes. Activity levels may relate to how much sampling of each shoal was needed by the test fish during decision making. Predation pressure may select for better decision makers to survive to larger size, or that older, larger fish have learned to make shoaling decisions more efficiently, and this, combined with their size relative to shoal-mates, and attractiveness as prey items influences shoaling

Analyzing ROC curves using the effective set-size model

Science.gov (United States)

Samuelson, Frank W.; Abbey, Craig K.; He, Xin

2018-03-01

The Effective Set-Size model has been used to describe uncertainty in various signal detection experiments. The model regards images as if they were an effective number (M*) of searchable locations, where the observer treats each location as a location-known-exactly detection task with signals having average detectability d'. The model assumes a rational observer behaves as if he searches an effective number of independent locations and follows signal detection theory at each location. Thus the location-known-exactly detectability (d') and the effective number of independent locations M* fully characterize search performance. In this model the image rating in a single-response task is assumed to be the maximum response that the observer would assign to these many locations. The model has been used by a number of other researchers, and is well corroborated. We examine this model as a way of differentiating imaging tasks that radiologists perform. Tasks involving more searching or location uncertainty may have higher estimated M* values. In this work we applied the Effective Set-Size model to a number of medical imaging data sets. The data sets include radiologists reading screening and diagnostic mammography with and without computer-aided diagnosis (CAD), and breast tomosynthesis. We developed an algorithm to fit the model parameters using two-sample maximum-likelihood ordinal regression, similar to the classic bi-normal model. The resulting model ROC curves are rational and fit the observed data well. We find that the distributions of M* and d' differ significantly among these data sets, and differ between pairs of imaging systems within studies. For example, on average tomosynthesis increased readers' d' values, while CAD reduced the M* parameters. We demonstrate that the model parameters M* and d' are correlated. We conclude that the Effective Set-Size model may be a useful way of differentiating location uncertainty from the diagnostic uncertainty in medical

Simple and cost-effective fabrication of size-tunable zinc oxide architectures by multiple size reduction technique

Directory of Open Access Journals (Sweden)

Hyeong-Ho Park, Xin Zhang, Seon-Yong Hwang, Sang Hyun Jung, Semin Kang, Hyun-Beom Shin, Ho Kwan Kang, Hyung-Ho Park, Ross H Hill and Chul Ki Ko

2012-01-01

Full Text Available We present a simple size reduction technique for fabricating 400 nm zinc oxide (ZnO architectures using a silicon master containing only microscale architectures. In this approach, the overall fabrication, from the master to the molds and the final ZnO architectures, features cost-effective UV photolithography, instead of electron beam lithography or deep-UV photolithography. A photosensitive Zn-containing sol–gel precursor was used to imprint architectures by direct UV-assisted nanoimprint lithography (UV-NIL. The resulting Zn-containing architectures were then converted to ZnO architectures with reduced feature sizes by thermal annealing at 400 °C for 1 h. The imprinted and annealed ZnO architectures were also used as new masters for the size reduction technique. ZnO pillars of 400 nm diameter were obtained from a silicon master with pillars of 1000 nm diameter by simply repeating the size reduction technique. The photosensitivity and contrast of the Zn-containing precursor were measured as 6.5 J cm−2 and 16.5, respectively. Interesting complex ZnO patterns, with both microscale pillars and nanoscale holes, were demonstrated by the combination of dose-controlled UV exposure and a two-step UV-NIL.

Simple and cost-effective fabrication of size-tunable zinc oxide architectures by multiple size reduction technique

International Nuclear Information System (INIS)

Park, Hyeong-Ho; Hwang, Seon-Yong; Jung, Sang Hyun; Kang, Semin; Shin, Hyun-Beom; Kang, Ho Kwan; Ko, Chul Ki; Zhang Xin; Hill, Ross H; Park, Hyung-Ho

2012-01-01

We present a simple size reduction technique for fabricating 400 nm zinc oxide (ZnO) architectures using a silicon master containing only microscale architectures. In this approach, the overall fabrication, from the master to the molds and the final ZnO architectures, features cost-effective UV photolithography, instead of electron beam lithography or deep-UV photolithography. A photosensitive Zn-containing sol–gel precursor was used to imprint architectures by direct UV-assisted nanoimprint lithography (UV-NIL). The resulting Zn-containing architectures were then converted to ZnO architectures with reduced feature sizes by thermal annealing at 400 °C for 1 h. The imprinted and annealed ZnO architectures were also used as new masters for the size reduction technique. ZnO pillars of 400 nm diameter were obtained from a silicon master with pillars of 1000 nm diameter by simply repeating the size reduction technique. The photosensitivity and contrast of the Zn-containing precursor were measured as 6.5 J cm −2 and 16.5, respectively. Interesting complex ZnO patterns, with both microscale pillars and nanoscale holes, were demonstrated by the combination of dose-controlled UV exposure and a two-step UV-NIL.

Global model for the lithospheric strength and effective elastic thickness

OpenAIRE

Magdala Tesauro; Mikhail Kaban; S. A. P. L. Cloetingh

2013-01-01

Global distribution of the strength and effective elastic thickness (Te) of the lithosphere are estimated using physical parameters from recent crustal and lithospheric models. For the Te estimation we apply a new approach, which provides a possibility to take into account variations of Young modulus (E) within the lithosphere. In view of the large uncertainties affecting strength estimates, we evaluate global strength and Te distributions for possible end-member ‘hard’ (HRM) and a ‘soft’ (SR...

Size-dependent response of foraminiferal calcification to seawater carbonate chemistry

Science.gov (United States)

Henehan, Michael J.; Evans, David; Shankle, Madison; Burke, Janet E.; Foster, Gavin L.; Anagnostou, Eleni; Chalk, Thomas B.; Stewart, Joseph A.; Alt, Claudia H. S.; Durrant, Joseph; Hull, Pincelli M.

2017-07-01

The response of the marine carbon cycle to changes in atmospheric CO2 concentrations will be determined, in part, by the relative response of calcifying and non-calcifying organisms to global change. Planktonic foraminifera are responsible for a quarter or more of global carbonate production, therefore understanding the sensitivity of calcification in these organisms to environmental change is critical. Despite this, there remains little consensus as to whether, or to what extent, chemical and physical factors affect foraminiferal calcification. To address this, we directly test the effect of multiple controls on calcification in culture experiments and core-top measurements of Globigerinoides ruber. We find that two factors, body size and the carbonate system, strongly influence calcification intensity in life, but that exposure to corrosive bottom waters can overprint this signal post mortem. Using a simple model for the addition of calcite through ontogeny, we show that variable body size between and within datasets could complicate studies that examine environmental controls on foraminiferal shell weight. In addition, we suggest that size could ultimately play a role in determining whether calcification will increase or decrease with acidification. Our models highlight that knowledge of the specific morphological and physiological mechanisms driving ontogenetic change in calcification in different species will be critical in predicting the response of foraminiferal calcification to future change in atmospheric pCO2.

Predictors of Citation Rate in Psychology: Inconclusive Influence of Effect and Sample Size.

Science.gov (United States)

Hanel, Paul H P; Haase, Jennifer

2017-01-01

In the present article, we investigate predictors of how often a scientific article is cited. Specifically, we focus on the influence of two often neglected predictors of citation rate: effect size and sample size, using samples from two psychological topical areas. Both can be considered as indicators of the importance of an article and post hoc (or observed) statistical power, and should, especially in applied fields, predict citation rates. In Study 1, effect size did not have an influence on citation rates across a topical area, both with and without controlling for numerous variables that have been previously linked to citation rates. In contrast, sample size predicted citation rates, but only while controlling for other variables. In Study 2, sample and partly effect sizes predicted citation rates, indicating that the relations vary even between scientific topical areas. Statistically significant results had more citations in Study 2 but not in Study 1. The results indicate that the importance (or power) of scientific findings may not be as strongly related to citation rate as is generally assumed.

Globalization

Directory of Open Access Journals (Sweden)

Tulio Rosembuj

2006-12-01

Full Text Available There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

Size effects on magnetoelectric response of multiferroic composite with inhomogeneities

Energy Technology Data Exchange (ETDEWEB)

Yue, Y.M. [Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Key Laboratory of Mechanics in Energy Engineering, Department of Mechanics, Shanghai University, Shanghai 200072 (China); Xu, K.Y., E-mail: kyxu@shu.edu.cn [Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Key Laboratory of Mechanics in Energy Engineering, Department of Mechanics, Shanghai University, Shanghai 200072 (China); Chen, T. [Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Key Laboratory of Mechanics in Energy Engineering, Department of Mechanics, Shanghai University, Shanghai 200072 (China); Aifantis, E.C. [Laboratory of Mechanics and Materials (LMM), Aristotle University of Thessaloniki, Thessaloniki GR-54124 (Greece); Michigan Technological University, Houghton, MI 49931 (United States); King Abdulaziz University, Jeddah 21589 (Saudi Arabia); School of Mechanics and Engineering, Southwest Jiaotong University, Chengdu, 610031 (China); International Laboratory for Modern Functional Materials, ITMO University, St. Petersburg 191002 (Russian Federation)

2015-12-01

This paper investigates the influence of size effects on the magnetoelectric performance of multiferroic composite with inhomogeneities. Based on a simple model of gradient elasticity for multiferroic materials, the governing equations and boundary conditions are obtained from an energy variational principle. The general formulation is applied to consider an anti-plane problem of multiferroic composites with inhomogeneities. This problem is solved analytically and the effective magnetoelectric coefficient is obtained. The influence of the internal length (grain size or particle size) on the effective magnetoelectric coefficients of piezoelectric/piezomagnetic nanoscale fibrous composite is numerically evaluated and analyzed. The results suggest that with the increase of the internal length of piezoelectric matrix (PZT and BaTiO{sub 3}), the magnetoelectric coefficient increases, but the rate of increase is ratcheting downwards. If the internal length of piezoelectric matrix remains unchanged, the magnetoelectric coefficient will decrease with the increase of internal length scale of piezomagnetic nonfiber (CoFe{sub 2}O{sub 3}). In a composite consisiting of a piezomagnetic matrix (CoFe{sub 2}O{sub 3}) reinforced with piezoelectric nanofibers (BaTiO{sub 3}), an increase of the internal length in the piezomagnetic matrix, results to a decrease of the magnetoelectric coefficient, with the rate of decrease diminishing.

Size effects on magnetoelectric response of multiferroic composite with inhomogeneities