WorldWideScience

Sample records for policy-induced structural change

  1. Organisational Structure & Change

    Science.gov (United States)

    National Centre for Vocational Education Research (NCVER), 2006

    2006-01-01

    Structural change is seen as a way to meet the challenges of the future that face many organisations. While some writers agree that broad-ranging structural change may not always transform an organisation or enhance its performance, others claim that innovation will be a major source of competitive advantage to organisations, particularly when…

  2. Social Structure and Social Change

    Science.gov (United States)

    Rogers, Everett M.

    1971-01-01

    Drawing on examples and evidence from social science research on the diffusion of ideas, social movements, and several other related fields, nine propositions dealing with the interrelationships between social structure and social change are explored. (Author/MB)

  3. Changing state structures: Outside in

    Science.gov (United States)

    Krasner, Stephen D.

    2011-01-01

    In explaining the development of institutional structures within states, social science analysis has focused on autochthonous factors and paid less attention to the way in which external factors, especially purposive agent-directed as opposed to more general environmental factors, can influence domestic authority structures. For international relations scholarship, this lacunae is particularly troubling or perhaps, just weird. If the international system is anarchical, then political leaders can pursue any policy option. In some cases, the most attractive option would be conventional state to state interactions, diplomacy, or war. In other instances, however, changing the domestic authority structures of other states might be more appealing. In some cases, domestic authority structures have been influenced through bargaining, and in others through power. Power may reflect either explicit agent-oriented decisions or social processes that reflect the practices, values, and norms of more powerful entities. PMID:22198756

  4. Growth, Employment and Structural Change

    DEFF Research Database (Denmark)

    Aggarwal, Aradhna

    2016-01-01

    This paper studies the decomposition of GSDP growth per capita in Punjab via-a-vis 15 other states in India during 1993–94 and 2011–12 in terms of employment and productivity growth. Specifically, it focuses on the role of employment growth and structural change in employment on economic growth...... but structural shifts have paid off well in terms of diversification of the economy and their contribution to labour productivity especially for manufacturing. Overall employment effect had been negative but this was essentially due to contraction in the labour force; the employment rate effect turned out...

  5. Structure change of fuel pellets

    International Nuclear Information System (INIS)

    Imanaka, Tetsuji

    1980-01-01

    The investigation of the broken pieces of fuel rods in Mihama No. 1 reactor was carried out in the Japan Atomic Energy Research Institute, and unexpectedly led to the post-irradiation tests. The investigation group of the Kyoto University Research Institute considers that the pursuit of the causes of accident by the government was insufficient, and the countermeasures are problematical, as the result of having examined various reports. In this study, the white foreign phase and swelling of cladding tubes were investigated, because these are especially important in view of the soundness of the fuel. Besides, the possibility of the oxidation of UO 2 pellets by cooling water was examined. It was found by metallographic test that the featuring phase different from UO 2 structure existed in the central part of pellets remaining in two broken fuel rod pieces. The report of JAERI judged that it is the product of solid phase reaction above a certain threshold temperature. The change of pellet structure observed in the white foreign phase and the swell of a cladding tube was caused by the oxidation of UO 2 pellets by primary coolant. The result of observation of the white foreign phase showed that it had been liquid phase at the time of the formation. From the thermodynamic examination based on oxygen potential, UO 2 is oxidized above 1100 deg C in the atmosphere of primary coolant. The liquid phase of the oxidized phase of UO 2 is formed above 1600 deg C. (Kako, I.)

  6. Diffusional changes of defect structure in solids

    International Nuclear Information System (INIS)

    Lyubov, B.Ya.

    1982-01-01

    Some problems of the theory of vacancy and impurity atoms diffusion in structure heterogeneous solidsi connected with changes in their defect structure, are reviewed. Two aspects of changes in the defect structure are discussed: an unconcervative movement of dislocations and a growth of damage of material continuity. Analytical solution methods in the theory of diffusional changes of defect structure in solids are illustrated as applied to hydrogen corrosion in steels, sintering kinetics, thermal conductivity theory [ru

  7. Structural changes, roles and challenges

    International Nuclear Information System (INIS)

    2000-01-01

    Statnett is facing great challenges in a Nordic and European integrated power market, with increasingly mighty commercial players. In a competing market there are conflicts between the socio-economic targets for Statkraft's activities and the commercial interests of Statnet's customers and other players in the power market. In the light of development, the connection lines between the customers and Statnett should be changed. Another problem is the legal competence problem that arises when the Oil and Energy Department (OED) works out the general policy at the same time as it owns Statkraft and Statnett and is the appellate body for the development decisions taken by the NVE (the Norwegian Water Resources and Energy Directorate). When comprehensive changes in Statkraft's company organisation and ownership are considered, special attention must be paid to the competence problem and to the risk of the commercial producers increasing their impact on how Statnett manages its role as a systems operator

  8. Structural Change in Southern Softwood Stumpage Markets

    Science.gov (United States)

    Douglas R. Carter

    1998-01-01

    The potential for structural change in southern stumpage market models has impacts on not only our basic understanding of those markets, but also on harvest, inventory and price projections, and related policy. In this paper, we test for structural change in both sawtimber and pulpwood softwood stumpage markets in the U.S. South over the period 1950-1994. Test...

  9. Volume changes in unrestrained structural lightweight concrete.

    Science.gov (United States)

    1964-08-01

    In this study a comparator-type measuring system was developed to accurately determine volume change characteristics of one structural lightweight concrete. The specific properties studied were the coefficient of linear thermal expansion and unrestra...

  10. Regional heterogeneity of arterial structural changes

    NARCIS (Netherlands)

    Daemen, M. J.; de Mey, J. G.

    1995-01-01

    Arterial structural changes in experimental models of hypertension and restenosis differ between vessel types and within vessels. Inspired by the diversity of short-term functional responses to vasoactive agents, hypotheses are presented with respect to the heterogeneity of structural alterations.

  11. The structural properties of sustainable, continuous change

    DEFF Research Database (Denmark)

    Håkonsson, Dorthe Døjbak; Klaas, Johann Peter; Carroll, Timothy

    2013-01-01

    Recent studies show that the relationship between structure and inertia in changing environments may be more complex than previously held and that the theoretical logics tying inertia with flexibility and efficiency remain incomplete. Using a computational model, this article aims to clarify...... this relationship by exploring what structural properties enable continuous change in inertia-generating organizations and what their performance consequences are in dynamic environments. The article has three main findings: First, employing managers who anticipate change is not enough to generate continuous change......; it is also necessary to raise both the rate of responsiveness and desired performance. Second, continuous change increases average organizational performance and reduces its variation. Third, organizations’ capacity for continuous change is counterintuitively limited by the organizations’ capacity to build...

  12. UV-induced structural changes in chromatin

    International Nuclear Information System (INIS)

    Lang, H.; Zimmer, C.; Vengerov, Yu.Yu.

    1985-01-01

    UV-induced structural alterations of chromatin were studied by means of CD, electron microscopic, and gel electrophoretic measurements. The results indicate that chromatin undergoes serious structural changes after irradiation even at very low fluences. In the low fluence range the structural transitions from the higher ordered chromatin structure to the unfolded state occur without detectable changes in the content of histone H1 and of the core histones. Histone H1 disappears only at fluences above 10 kJ/m 2 . Furthermore, DNA in chromatin is much more sensitive against UV-irradiation and shows a higher degree of strand scission relative to free DNA. While fragmentation in free DNA occurs at fluences above 15 kJ/m 2 , it occurs even at 5.5 kJ/m 2 in the case of chromatin. The biological meaning of the observed UV-induced structural alterations of chromatin is discussed. (author)

  13. Structural changes of homodimers in the PDB.

    Science.gov (United States)

    Koike, Ryotaro; Amemiya, Takayuki; Horii, Tatsuya; Ota, Motonori

    2018-04-01

    Protein complexes are involved in various biological phenomena. These complexes are intrinsically flexible, and structural changes are essential to their functions. To perform a large-scale automated analysis of the structural changes of complexes, we combined two original methods. An application, SCPC, compares two structures of protein complexes and decides the match of binding mode. Another application, Motion Tree, identifies rigid-body motions in various sizes and magnitude from the two structural complexes with the same binding mode. This approach was applied to all available homodimers in the Protein Data Bank (PDB). We defined two complex-specific motions: interface motion and subunit-spanning motion. In the former, each subunit of a complex constitutes a rigid body, and the relative movement between subunits occurs at the interface. In the latter, structural parts from distinct subunits constitute a rigid body, providing the relative movement spanning subunits. All structural changes were classified and examined. It was revealed that the complex-specific motions were common in the homodimers, detected in around 40% of families. The dimeric interfaces were likely to be small and flat for interface motion, while large and rugged for subunit-spanning motion. Interface motion was accompanied by a drastic change in contacts at the interface, while the change in the subunit-spanning motion was moderate. These results indicate that the interface properties of homodimers correlated with the type of complex-specific motion. The study demonstrates that the pipeline of SCPC and Motion Tree is useful for the massive analysis of structural change of protein complexes. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Structural Changes in Serbian Industry during Transition

    Directory of Open Access Journals (Sweden)

    Ivan Nikolić

    2013-07-01

    Full Text Available Transition is a complex process whereby a country in transition is stimulating structural changes wishing to achieve economic growth and improved social wellbeing. In this paper the authors aim to show that during transition in Serbia there such changes in the structure of manufacturing industry occurred, which resulted with only modest ​​growth that in fact was slower than in other transitional countries. By the means of theoretical and empirical approach – deductive methods, statistical and mathematical evaluation the authors have come to conclusion that structural changes did not improve industry branches like the hi-tech industry that contribute the most to PPP generation. At the same time, some low productive industries have gained on importance, therefore keeping the standard on the low levels without possibility to rapidly converge towards EU average, which was set as an ultimate goal of transition in Serbia.

  15. Migraine and structural changes in the brain

    DEFF Research Database (Denmark)

    Bashir, Asma; Lipton, Richard B; Ashina, Sait

    2013-01-01

    To evaluate the association between migraine without aura (MO) and migraine with aura (MA) and 3 types of structural brain abnormalities detected by MRI: white matter abnormalities (WMAs), infarct-like lesions (ILLs), and volumetric changes in gray and white matter (GM, WM) regions....

  16. Gazelles, Industry Growth and Structural Change

    NARCIS (Netherlands)

    Bos, J.W.B.; Stam, E.

    2011-01-01

    This paper examines to what extent gazelles are the drivers of the growth of industries and structural change. To this purpose we analyze gazelles over a 12 year period (annually from 1997 until 2008) in the Netherlands, and relate them to the dynamics in employment per industry. We use a panel

  17. Investment specific technological progress and structural change

    Directory of Open Access Journals (Sweden)

    Ricardo Silva Azevedo Araujo

    2010-12-01

    Full Text Available In this paper we introduce investment specific technical progress into Pasinetti's model of structural change. Our aim is to assess the effects of embodied technical progress on economic growth and macroeconomic variables. Our findings suggest that despite the fact that this type of technical progress increases the productivity of capital, it has negative effects on conditions that promote full employment.

  18. Entrepreneurship, structural change, and economic growth

    NARCIS (Netherlands)

    Noseleit, Florian

    The ability to adjust to structural change is vital to economic development, and entries can be active participants in this process. While the importance of factor reallocations for growth is widely discussed, the role of entrepreneurs in managing these reallocations is currently not well

  19. Structural modifications leading to changes in supramolecular ...

    Indian Academy of Sciences (India)

    1347–1356. c Indian Academy of Sciences. Structural modifications leading to changes in supramolecular aggregation of thiazolo[3, 2-a]pyrimidines: Insights into their conformational features. H NAGARAJAIAH and NOOR SHAHINA BEGUM. ∗. Department of Studies in Chemistry, Bangalore University, Bangalore 560 001, ...

  20. Structural modelling of economic growth: Technological changes

    Directory of Open Access Journals (Sweden)

    Sukharev Oleg

    2016-01-01

    Full Text Available Neoclassical and Keynesian theories of economic growth assume the use of Cobb-Douglas modified functions and other aggregate econometric approaches to growth dynamics modelling. In that case explanations of economic growth are based on the logic of the used mathematical ratios often including the ideas about aggregated values change and factors change a priori. The idea of assessment of factor productivity is the fundamental one among modern theories of economic growth. Nevertheless, structural parameters of economic system, institutions and technological changes are practically not considered within known approaches, though the latter is reflected in the changing parameters of production function. At the same time, on the one hand, the ratio of structural elements determines the future value of the total productivity of the factors and, on the other hand, strongly influences the rate of economic growth and its mode of innovative dynamics. To put structural parameters of economic system into growth models with the possibility of assessment of such modes under conditions of interaction of new and old combinations is an essential step in the development of the theory of economic growth/development. It allows forming stimulation policy of economic growth proceeding from the structural ratios and relations recognized for this economic system. It is most convenient in such models to use logistic functions demonstrating the resource change for old and new combination within the economic system. The result of economy development depends on starting conditions, and on institutional parameters of velocity change of resource borrowing in favour of a new combination and creation of its own resource. Model registration of the resource is carried out through the idea of investments into new and old combinations.

  1. Climate adaptation and policy-induced inflation of coastal property value.

    Directory of Open Access Journals (Sweden)

    Dylan E McNamara

    Full Text Available Human population density in the coastal zone and potential impacts of climate change underscore a growing conflict between coastal development and an encroaching shoreline. Rising sea-levels and increased storminess threaten to accelerate coastal erosion, while growing demand for coastal real estate encourages more spending to hold back the sea in spite of the shrinking federal budget for beach nourishment. As climatic drivers and federal policies for beach nourishment change, the evolution of coastline mitigation and property values is uncertain. We develop an empirically grounded, stochastic dynamic model coupling coastal property markets and shoreline evolution, including beach nourishment, and show that a large share of coastal property value reflects capitalized erosion control. The model is parameterized for coastal properties and physical forcing in North Carolina, U.S.A. and we conduct sensitivity analyses using property values spanning a wide range of sandy coastlines along the U.S. East Coast. The model shows that a sudden removal of federal nourishment subsidies, as has been proposed, could trigger a dramatic downward adjustment in coastal real estate, analogous to the bursting of a bubble. We find that the policy-induced inflation of property value grows with increased erosion from sea level rise or increased storminess, but the effect of background erosion is larger due to human behavioral feedbacks. Our results suggest that if nourishment is not a long-run strategy to manage eroding coastlines, a gradual removal is more likely to smooth the transition to more climate-resilient coastal communities.

  2. Climate Adaptation and Policy-Induced Inflation of Coastal Property Value

    Science.gov (United States)

    McNamara, Dylan E.; Gopalakrishnan, Sathya; Smith, Martin D.; Murray, A. Brad

    2015-01-01

    Human population density in the coastal zone and potential impacts of climate change underscore a growing conflict between coastal development and an encroaching shoreline. Rising sea-levels and increased storminess threaten to accelerate coastal erosion, while growing demand for coastal real estate encourages more spending to hold back the sea in spite of the shrinking federal budget for beach nourishment. As climatic drivers and federal policies for beach nourishment change, the evolution of coastline mitigation and property values is uncertain. We develop an empirically grounded, stochastic dynamic model coupling coastal property markets and shoreline evolution, including beach nourishment, and show that a large share of coastal property value reflects capitalized erosion control. The model is parameterized for coastal properties and physical forcing in North Carolina, U.S.A. and we conduct sensitivity analyses using property values spanning a wide range of sandy coastlines along the U.S. East Coast. The model shows that a sudden removal of federal nourishment subsidies, as has been proposed, could trigger a dramatic downward adjustment in coastal real estate, analogous to the bursting of a bubble. We find that the policy-induced inflation of property value grows with increased erosion from sea level rise or increased storminess, but the effect of background erosion is larger due to human behavioral feedbacks. Our results suggest that if nourishment is not a long-run strategy to manage eroding coastlines, a gradual removal is more likely to smooth the transition to more climate-resilient coastal communities. PMID:25806944

  3. Climate adaptation and policy-induced inflation of coastal property value.

    Science.gov (United States)

    McNamara, Dylan E; Gopalakrishnan, Sathya; Smith, Martin D; Murray, A Brad

    2015-01-01

    Human population density in the coastal zone and potential impacts of climate change underscore a growing conflict between coastal development and an encroaching shoreline. Rising sea-levels and increased storminess threaten to accelerate coastal erosion, while growing demand for coastal real estate encourages more spending to hold back the sea in spite of the shrinking federal budget for beach nourishment. As climatic drivers and federal policies for beach nourishment change, the evolution of coastline mitigation and property values is uncertain. We develop an empirically grounded, stochastic dynamic model coupling coastal property markets and shoreline evolution, including beach nourishment, and show that a large share of coastal property value reflects capitalized erosion control. The model is parameterized for coastal properties and physical forcing in North Carolina, U.S.A. and we conduct sensitivity analyses using property values spanning a wide range of sandy coastlines along the U.S. East Coast. The model shows that a sudden removal of federal nourishment subsidies, as has been proposed, could trigger a dramatic downward adjustment in coastal real estate, analogous to the bursting of a bubble. We find that the policy-induced inflation of property value grows with increased erosion from sea level rise or increased storminess, but the effect of background erosion is larger due to human behavioral feedbacks. Our results suggest that if nourishment is not a long-run strategy to manage eroding coastlines, a gradual removal is more likely to smooth the transition to more climate-resilient coastal communities.

  4. Radiation-induced structural changes, (2)

    International Nuclear Information System (INIS)

    Ogasawara, M.; Matsuyama, T.

    1992-11-01

    This seminar is aimed at understanding both the physical and chemical aspects of the structural changes of materials induced by photons or ionizing radiation. The seminar was held on December 19th, 1991 and from February 13 to 14th, 1992 in this institute. The most active areas of the material science, in addition to the previous subjects, such as organic superconductors, silicon-based polymers, and fullerenes were included in this seminar. (J.P.N.)

  5. Outlook for activity and structural change

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The level of energy-using activities is continuing to increase throughout the world, but the rates of likely growth differ among regions. Over the next 20 years, manufacturing production is expected to grow at a rapid pace in parts of the developing world, and moderately in the OECD countries. In the Former East Bloc, it seems likely to stagnate or decline for much of the 1990s, but could then grow at a moderate pace if the transition to a market economy is successfully managed. Domestic passenger travel seems likely to increase everywhere, and growth in international travel will be especially strong. Freight transport activity is difficult to evaluate in the aggregate, since the composition of goods changes over time, but increase is expected in all regions, especially in the developing countries. Structural change within sectors will have significant impacts on energy use. In manufacturing, faster growth in light industry will lead to lower energy intensity in the OECD countries and especially in the Former East Bloc. The outlook in the LDCs suggests somewhat higher growth in energy-intensive industries, but this trend will vary among countries. In passenger travel, structural change is pointing toward higher energy intensity in most of the world as the role of automobiles and air travel continues to grow. Increase in the use of trucks is pushing in a similar direction in freight transport. In the residential sector, structural change will have only a moderate impact in the OECD countries, where per capita levels of home services are already high, but will push energy use significantly upward in the LDCs, and to a lesser extent, in the Former East Bloc. 17 refs., 4 figs., 1 tab

  6. GROWTH AND STRUCTURAL CHANGE IN SAARC ECONOMIES

    Directory of Open Access Journals (Sweden)

    Upinder SAWHNEY

    2010-07-01

    Full Text Available This paper aims to analyze the growth and structural changes in the SAARC countries in the last two decades. Afghanistan has not been included in the study as it became the member of SAARC only in 2007. In view of the fact that India is emerging as one of the rapidly growing economies, it is important to study the changes, if any, in the economic structure of its neighbouring countries. The structural transformation in these countries can be defined in terms of certain common indicators: a declining share of agriculture in GDP and value added in the economy, rural-tourban migration that stimulates the process of urbanization; the rise of a modern industrial and service economy; and a demographic transition from high rates of births and deaths to low rates of births and deaths. Certain other economic indicators including saving and capital formation as well as their debt-GDP ratios will be reviewed over a period of last two decades.

  7. Structural changes in wood during ozonation

    Science.gov (United States)

    Ben'ko, E. M.; Manisova, O. R.; Murav'eva, G. P.; Lunin, V. V.

    2013-07-01

    It is found that ozone treatment of aspen wood leads to changes in its structural characteristics, i.e., its specific surface area and the crystallinity index of cellulose. Using optical microscopy, it is shown that ozonation is accompanied by a decrease in the average size and visible surface of wood particles. The values for the specific area of the outer surface of samples are calculated. The specific surface area available to the enzyme molecules is determined from data on the adsorption of inert protein hemoglobin on wood. It is shown that this value is an order of magnitude higher than that of the outer surface and increases considerably for an ozonized sample. Based on the results from X-ray analysis, it is established that the structure of cellulose is disordered during ozone delignification, as is indicated by a reduction in the crystallinity index and crystallite sizes.

  8. Changing optical band structure with single photons

    Science.gov (United States)

    Albrecht, Andreas; Caneva, Tommaso; Chang, Darrick E.

    2017-11-01

    Achieving strong interactions between individual photons enables a wide variety of exciting possibilities in quantum information science and many-body physics. Cold atoms interfaced with nanophotonic structures have emerged as a platform to realize novel forms of nonlinear interactions. In particular, when atoms are coupled to a photonic crystal waveguide, long-range atomic interactions can arise that are mediated by localized atom-photon bound states. We theoretically show that in such a system, the absorption of a single photon can change the band structure for a subsequent photon. This occurs because the first photon affects the atoms in the chain in an alternating fashion, thus leading to an effective period doubling of the system and a new optical band structure for the composite atom-nanophotonic system. We demonstrate how this mechanism can be engineered to realize a single-photon switch, where the first incoming photon switches the system from being highly transmissive to highly reflective, and analyze how signatures can be observed via non-classical correlations of the outgoing photon field.

  9. Soil structure changes evaluated with computed tomography

    International Nuclear Information System (INIS)

    Pires, Luiz Fernando

    2010-01-01

    The objective of this work was to evaluate in millimetric scale changes in soil bulk density and porosity, using the gamma-ray computed tomography in soil samples with disturbed structure due to wetting and drying (W-D) cycles. Soil samples with 98.1 cm 3 were sieved using a 2 mm mesh and homogeneously packed in PVC cylinders. Soil samples were submitted to 1, 2, and 3 W-D cycles. Control samples were not submitted to W-D cycles. After repetitions of W-D cycles, soil sample porosity decreased and soil layers became denser. Computed tomography allowed a continuous analysis of soil bulk density and also soil porosity along millimetric (0.08 cm) layers, what cannot be provided by traditional methods used in soil physics. (author)

  10. CHANGES IN STRUCTURE OF ROMANIA'S INTERNATIONAL TRADE

    Directory of Open Access Journals (Sweden)

    CECILIA IRINA RABONTU

    2014-05-01

    Full Text Available Evolution of structural changes in Romanian trade is somewhat interesting if you look at it from the perspective of mutations that occurred in the categories of goods and services subject to international trade. After the Revolution of 1989, the Romanian economy has gone through dramatic changes that had determinate a total reconfiguration of foreign trade. At the same time, the economic instability has had further repercussions on the Romanian economy manifested through higher prices, reduced wages or earnings, reduced employment and rising unemployment, increasing interest rates on loans due to the devaluation of the national currency, increase value-added tax, consumption reduction etc. We proposed in this paper an analyze for a significant period of time evolution of international trade in goods and services of Romania in order to establish the main categories of goods traded but Romania's main trading partners, too. In order to achieve the central goal of this paper we will use statistical data found in the databases provided by the WTO, Eurostat and the National Statistical Institutes and statistical methods to support our initiative.

  11. Structural change in Dutch agriculture; impact on farm level statistics

    NARCIS (Netherlands)

    Vrolijk, H.C.J.; Poppe, K.J.

    2016-01-01

    Structural change has been a constant factor in agriculture, the Netherlands included. For decades the number of farms has decreased and the size of farms has increased. Agricultural statistics help to analyse and understand structural change, but at the same time structural change affects and to

  12. [Crystallographic evaluation of structural changes in water].

    Science.gov (United States)

    Farashchuk, N F; Rakhmanin, Yu A; Savostikova, O N; Telenkova, O G

    2014-01-01

    The study of the structural state of tap water that has been stored for two days in the packaging materials of various type and in different conditions, was performed with the use of crystallographic method for the investigation of liquids based on a special approach for dehydration of the drop, which is a fixed thin "slice" of the examines liquid. Most organized crystallographic pattern was shown to observe in a drop of water after treatment Bioptron lamp (content of liquid-crystal associates (LCA)--6.90 ± 0.23), and stored in a silver vessel (content LCA--6.28 ± 0.17), and the least organized, almost amorphous precipitate is formed in a drop of water stored in plastic containers (content LCA--2.92 ± 0.15%). Basing on the obtained results, it can be concluded that the crystallographic method can be used for the identification of qualitative changes occurring in liquid water under the influence of various physical factors, for the identification of the rationality of the use of hereafter sophisticated quantitative techniques.

  13. The Theoretical Foundations of Structural Changes in Economy

    Directory of Open Access Journals (Sweden)

    Khaustova Viktoriia Ye.

    2017-12-01

    Full Text Available The article is aimed at defining the theoretical foundations of structural changes in economy. It has been proved that structural policy of the State is one of the main directions influencing the structure of economy, balancing its proportions, and ensuring progressive development. The components of structural policy have been defined. Genesis of scientific directions of researching the structure of economy was considered. The interpretation of the concept of «structure of economy» in the works of scientists was studied. The classification of particular structures of the national industrial complex was considered. It has been proved that the main role in the analysis of structural changes should be given to the structure of economy (of industrial complex, according to the types of economic activity. The interpretations of the concepts of «structural transformations», «structural shifts», «structural changes», «structural crisis» in the economy have been clarified. The functions of structural crises have been considered. The dynamics of changes in structural shifts were researched. The classification of structural shifts in the economy was considered. An interpretation of progressive structural changes has been suggested.

  14. Structural changes and volatility transmission in crude oil markets

    Science.gov (United States)

    Kang, Sang Hoon; Cheong, Chongcheul; Yoon, Seong-Min

    2011-11-01

    This study examines the influence of structural changes in volatility on the transmission of information in two crude oil prices. In an effort to assess the impact of these structural changes, we first identify the time points at which structural changes in volatility occurred using the ICSS algorithm, and then incorporate this information into our volatility modeling. From the estimation results using a bi-variate GARCH framework with and without structural change dummies, we find that the degree of persistence of volatility can be reduced via the incorporation of these structural changes in the volatility model. In this direction, we conclude that ignoring structural changes may distort the direction of information inflow and volatility transmission between crude oil markets.

  15. Fostering structural change? China's divergence and convergence ...

    African Journals Online (AJOL)

    The paper analyses the divergence and convergence of the characteristics of China's economic relationships with Africa – trade, investment and aid – with Africa's 'traditional' partners, i.e. Western industrialised countries. It argues that these relationships may foster structural transformation of African economies. The latter ...

  16. The Changing Occupational Structure of Amish Males.

    Science.gov (United States)

    Kreps, George M.; And Others

    1994-01-01

    Surveys of businesses and adult Amish males in Holmes and Wayne counties (Ohio) indicate that farming is declining as the primary occupation for Amish males and that the Amish occupational structure is becoming more complex as more Amish males work away from home. Possible impacts on Amish society, such as increased need for formal education, are…

  17. Upgrade and Design of Coastal Structures Exposed to Climate Changes

    DEFF Research Database (Denmark)

    Nørgaard, Jørgen Quvang Harck

    This thesis "Upgrade and Design of Coastal Structures Exposed to Climate Changes" evaluates the performance of existing types of structures when exposed to climate changes. This includes also the potential of using cost‐sharing multipurpose structures for protection against the effects of future...... climate changes. The thesis consists of three parts. The first part evaluates the performance of existing design formulae for estimation of wave actions on structures, especially in shallow water since these structures are most vulnerable to the rising sea water levels caused by climate changes. Existing...... of coastal protection structures, which are extended to a wider range of wave conditions, and which can be used to more accurately estimate the influence from climate changes. In the second part of the thesis, the extended and modified formulae are used in case studies to evaluate the influence from climate...

  18. Entrepreneurship, structural changes and tax payments

    Directory of Open Access Journals (Sweden)

    Shirokov Ivan Olegovich

    2015-04-01

    Full Text Available The article deals with the problem of developing a business environment across industries. The characteristic of transformation as a result of resource constraints and the process of self-organization of ecological type. Held in the formalization of variational suggesting adequacy coenosis optimization theory structure of the business environment on the basis of fiscal restraint. We propose a streaming algorithm for determining the boundary size of the tax rate.

  19. Probing structural changes of self assembled i-motif DNA

    KAUST Repository

    Lee, Iljoon

    2015-01-01

    We report an i-motif structural probing system based on Thioflavin T (ThT) as a fluorescent sensor. This probe can discriminate the structural changes of RET and Rb i-motif sequences according to pH change. This journal is

  20. Agricultural Structural Change: Impact on the Rural Environment.

    Science.gov (United States)

    Knickel, Karlheim

    1990-01-01

    Examines indicators and impacts of agricultural change on environment. Links environmental quality to farm structure and size, and rural cultural values. Examines correlation between part-time farming and land structure and quality. Examines policies' effect on agricultural change. Recommends incorporation of environmental policies into…

  1. Upgrade and Design of Coastal Structures Exposed to Climate Changes

    DEFF Research Database (Denmark)

    Nørgaard, Jørgen Quvang Harck

    This thesis “Upgrade and Design of Coastal Structures Exposed to Climate Changes” evaluates the performance of existing types of structures when exposed to climate changes. This includes also the potential of using cost‐sharing multipurpose structures for protection against the effects of future...... climate changes. The thesis consists of three parts. The first part evaluates the performance of existing design formulae for estimation of wave actions on structures, especially in shallow water since these structures are most vulnerable to the rising sea water levels caused by climate changes. Existing...... of coastal protection structures, which are extended to a wider range of wave conditions, and which can be used to more accurately estimate the influence from climate changes. In the second part of the thesis, the extended and modified formulae are used in case studies to evaluate the influence from climate...

  2. Sustainable urban structures to challenge climate change

    Directory of Open Access Journals (Sweden)

    Emil CREANGA

    2012-07-01

    Full Text Available Public spaces within the city in all their form of different types - streets, boulevards, squares, plazas, market places, green areas - are the backbone of cities. Over the centuries buildings defined the shape and quality of public spaces, valorising them in various ways. The post-modern development of urban form generated a great number of “urban spaces”, where there is no longer correspondence between architectural forms and social and political messages: shopping malls and theme parks, inner public spaces, strip developments etc. Urban sprawl accompanied by loss of agricultural/rural land and its impact on the environment are serious concerns for most cities over Europe. To strike the right balance between inner city regeneration, under-use of urban land in the old abandoned sites and the ecological benefits that accompany the new private business initiatives in suburban areas, is one of the major challenges confronting cities in Europe. The paper will analyze the complex relations between architecture and public space, in an attempt to understand how traditional urban structures, public and green spaces, squares and streets, could provide orientation for quality-oriented regeneration. Case in point is Bucharest - capital city of Romania - where aggressive intervention in the urban structure during the 1980s disrupted the fabric of the city. The investigation is oriented towards fundamental questions such as: how to secure and preserve sites that serve as initial points in upgrading processes, how to balance private investment criteria and the quality interests of the urban communities. The major aim is to provide a support for decision making in restoring the fundamental role of public urban space in shaping urban form and supporting community life.

  3. A Structural Equation Model of Conceptual Change in Physics

    Science.gov (United States)

    Taasoobshirazi, Gita; Sinatra, Gale M.

    2011-01-01

    A model of conceptual change in physics was tested on introductory-level, college physics students. Structural equation modeling was used to test hypothesized relationships among variables linked to conceptual change in physics including an approach goal orientation, need for cognition, motivation, and course grade. Conceptual change in physics…

  4. Intermolecular Structural Change for Thermoswitchable Polymeric Photosensitizer

    Energy Technology Data Exchange (ETDEWEB)

    Park, Wooram; Park, Sin-Jung [Center; Cho, Soojeong; Shin, Heejun [Center; Jung, Young-Seok [Center; Lee, Byeongdu [X-ray; Na, Kun [Center; Kim, Dong-Hyun

    2016-08-17

    A switchable photosensitizer (PS), which can be activated at a spe-cific condition beside light, has tremendous advantages for photo-dynamic therapy (PDT). Herein, we developed a thermo-switchable polymeric photosensitizer (T-PPS) by conjugating PS (Pheophor-bide-a, PPb-a) to a temperature-responsive polymer backbone of biocompatible hydroxypropyl cellulose (HPC). Self-quenched PS molecules linked in close proximity by pi-pi stacking in T-PPS were easily transited to an active monomeric state by the tempera-ture induced phase transition of polymer backbones. The tempera-ture responsive inter-molecular interaction changes of PS molecules in T-PPS were demonstrated in synchrotron small-angle X-ray scattering (SAXS) and UV-Vis spectrophotometer analysis. The T-PPS allowed switchable activation and synergistically enhanced cancer cell killing effect at the hyperthermia temperature (45 °C). Our developed T-PPS has the considerable potential not only as a new class of photomedicine in clinics but also as a biosensor based on temperature responsiveness.

  5. Employee experience of structural change in two Norwegian hospitals.

    Science.gov (United States)

    Roald, J; Edgren, L

    2001-01-01

    Advances in medical and technological procedures, together with changes in demography, demand structural changes in the Nordic health care systems. Few studies have focused on employee perceptions of these structural changes. This study aims to describe employee reactions following a merger between two Norwegian hospitals. A Grounded theory approach has been used in this study. The theoretical model is based on empirical data collected from employees directly affected by the structural change process. Employee resistance was found to be the core category. Three categories were found in relation to this core category; goal uncertainty, organizational culture and individual insecurity. Different perceptions and interpretations of vaguely formulated goals lead to employee resistance. The difference between the organizational cultures in the two hospitals impeded the merger according to the project plan, and very few positive results could be seen. Individual insecurity regarding the future was experienced in connection with the implementation of structural change. The authors propose a strategy to counteract resistance in similar mergers.

  6. Dynamic Changes in Sarcoplasmic Reticulum Structure in Ventricular Myocytes

    Directory of Open Access Journals (Sweden)

    Amanda L. Vega

    2011-01-01

    sarcoplasmic reticulum (SR and the sarcolemma where Ca2+ release is activated. Here, we tested the hypothesis that the SR is a structurally inert organelle in ventricular myocytes. Our data suggest that rather than being static, the SR undergoes frequent dynamic structural changes. SR boutons expressing functional ryanodine receptors moved throughout the cell, approaching or moving away from the sarcolemma of ventricular myocytes. These changes in SR structure occurred in the absence of changes in [Ca2+] during EC coupling. Microtubules and the molecular motors dynein and kinesin 1(Kif5b were important regulators of SR motility. These findings support a model in which the SR is a motile organelle capable of molecular motor protein-driven structural changes.

  7. Impact of the structural changes on the nuclear safety

    International Nuclear Information System (INIS)

    Ziakova, M.

    2005-01-01

    In this presentation author deals with impact of the structural changes (privatization of the Slovenske Elektrarne, a.s.) and new Atomic law (541/2004 Coll. Laws) on the nuclear safety in the Slovak Republic.

  8. Estimating energy elasticity with structural changes in Japan

    International Nuclear Information System (INIS)

    Yamaguchi, Keiko

    2007-01-01

    The purpose of this paper is to estimate energy elasticity in Japan taking into account structural changes. We employ a residual-based cointegration model developed by Gregory and Hansen [Gregory, Allan W., Hansen, Bruce E., 1996. Residual-based tests for cointegration in models with regime shifts, Journal of Econometrics. 70, 99-126]. The empirical results show that the three variables have a stable relationship in the long term when considering structural changes in the second quarter of 1993. As compared with the values obtained in previous studies, the income elasticity is higher and the price elasticity is lower. From our analysis, we can confirm whether a carbon tax will meet the objective of the Kyoto Protocol. In conclusion, the tax rate required in the case without structural changes is lower than that in the case with structural changes. (author)

  9. Structural changes of linear DNA molecules induced by cisplatin

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhiguo, E-mail: cn.zguoliu@yahoo.com [State Engineering Laboratory of Bio-Resource Eco-Utilization, Harbin 150040 (China); Engineering Research Center of Forest Bio-preparation, Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Liu, Ruisi; Zhou, Zhen; Zu, Yuangang; Xu, Fengjie [State Engineering Laboratory of Bio-Resource Eco-Utilization, Harbin 150040 (China); Engineering Research Center of Forest Bio-preparation, Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China)

    2015-02-20

    Interaction between long DNA molecules and activated cisplatin is believed to be crucial to anticancer activity. However, the exact structural changes of long DNA molecules induced by cisplatin are still not very clear. In this study, structural changes of long linear double-stranded DNA (dsDNA) and short single-stranded DNA (ssDNA) induced by activated cisplatin have been investigated by atomic force microscopy (AFM). The results indicated that long DNA molecules gradually formed network structures, beads-on-string structures and their large aggregates. Electrostatic and coordination interactions were considered as the main driving forces producing these novel structures. An interesting finding in this study is the beads-on-string structures. Moreover, it is worth noting that the beads-on-string structures were linked into the networks, which can be ascribed to the strong DNA–DNA interactions. This study expands our knowledge of the interactions between DNA molecules and cisplatin. - Highlights: • We investigate structural changes of dsDNA and ssDNA induced by cisplatin. • AFM results indicated long dsDNA formed network, beads-on-string and aggregates. • ssDNA can form very similar structures as those of long linear dsDNA. • A possible formation process of theses novel structure is proposed.

  10. Testing for structural change in the presence of long memory

    OpenAIRE

    Krämer, Walter; Sibbertsen, Philipp

    2000-01-01

    We derive the limiting null distributions of the standard and OLS-based CUSUM-tests for structural change of the coefficients of a linear regression model in the context of long memory disturbances. We show that both tests behave fundamentally different in a long memory environment, as compared to short memory, and that long memory is easily mistaken for structural change when standard critical values are employed.

  11. New structural changes in Kazakhstan petroleum and gas industry management

    International Nuclear Information System (INIS)

    Nadirov, N.K.; Konaev, Eh.N.

    1998-01-01

    The basic stags of structural changes in Kazakhstan petroleum and gas industry management are considered. It is shown, that in new economic situation the traditional branch scheme of management became out date and does not meet demands up the times. The spent structural changes in petroleum and gas industry management will promote to strengthening of strategic role of hydrocarbon raw material production and processing in prospect. (author)

  12. Original Paper Floristic and structural changes in secondary forests ...

    African Journals Online (AJOL)

    http://ajol.info/index.php/ijbcs http://indexmedicus.afro.who.int. Floristic and structural changes ... This study aims at providing quantitative information on floristic composition and structure of the Lama secondary forests (Benin), so as to contribute to ...... Seedling recruitment in a hurricane- driven tropical forest: light limitation,.

  13. Detection of changes in the structure of a system according to changes of its flicker noise

    International Nuclear Information System (INIS)

    Kolodiy, Z.A.

    2008-01-01

    The results of computer simulations of a chaotic motion of elementary particles in the systems with chaotic or ordered structure are presented. The conclusion about the possibility to use the flicker noise of a system for the qualitative estimation of its inner structure and changes in the structure is made

  14. Bone structure changes in iliac crest grafts combined with implants

    NARCIS (Netherlands)

    Verhoeven, Jan Willem; Ruijter, Jan M.; Koole, Ronald; de Putter, Cornelis; Cune, Marco S.

    2010-01-01

    Remodeling of onlay grafts combined with implants to the mandible results in predictable changes in the graft's radiographic density. We studied the relationship between changes in radiographic density and trabecular structure during the first year after onlay grafting with simultaneous implant

  15. Structural, physical, functional and nutraceutical changes of freeze ...

    African Journals Online (AJOL)

    This review examines the structural, physical, functional and nutraceutical changes of lyophilized fruits. Collapse, porosity, color, glass transition temperature, rehydration capacity, ability to retain water, volatile compounds, phenolic compounds, ascorbic acid, and beta-carotene, were defined, and the causes of changes in ...

  16. Does competitive entry structurally change key marketing metrics?

    NARCIS (Netherlands)

    Kornelis, M.; Dekimpe, de M.G.; Leeflang, P.S.H.

    2008-01-01

    To what extent does competitive entry create a structural change in keymarketingmetrics? New players may just be a temporal nuisance to incumbents, but could also fundamentally change the latter's performance evolution, or induce them to permanently alter their spending levels and/or pricing

  17. Does competitive entry structurally change key marketing metrics?

    NARCIS (Netherlands)

    Kornelis, Marcel; Dekimpe, Marnik G.; Leeflang, Peter S. H.

    To what extent does competitive entry create a structural change in key marketing metrics? New players mayjust be a temporal nuisance to incumbents, but could also fundamentally change the latter's performance evolution, or induce them to permanently alter their spending levels and/or pricing

  18. Architecture, Structure, and Loads: A Moment of Change?

    Directory of Open Access Journals (Sweden)

    Marci S. Uihlein

    2012-12-01

    Full Text Available Architecture and building structure have a unique, complicated, and intertwined history. Architectural innovations can drive the development of structural systems and structural advancements can push architecture forward. Rem Koolhaas, writing about one of his primary engineering collaborators in 2002, stated that this collaborator “almost single‐handedly shifted the ground in engineering — a domain which the earth moves very rarely — and therefore enabled architecture to be imagined differently.”1 There are two ideas embedded in this quote. The first is that building structure and those who design it are entrenched in a way of practice that seldom varies. The second is that the view of structure is changing and this change has the potential to allow architecture to make a significant transformation. Ten years later, the question remains, is structure changing, and if so, how and what metrics can be used to establish this? Digital technology and fabrication advancements have led to an exploration of building structure and material. Architects are creating buildings once thought impossible to build. Through experimentation, new forms and roof systems are being created. Does this form creation have a larger meaning? One indicator of this might be found in the way loads and load paths are conceived. When starting a project, the primary determinants are the understanding of the loads created by the engineer and the selection of a structural system to support them. Can an examination of loads be used to evaluate change in structure? This investigation will begin with a brief discussion of loads and will analyze two recently constructed works as case studies. The structural systems in these buildings will be examined to see if the conception of loads and the philosophy behind the system is evolving.

  19. Structural brain changes in aging: courses, causes and cognitive consequences.

    Science.gov (United States)

    Fjell, Anders M; Walhovd, Kristine B

    2010-01-01

    The structure of the brain is constantly changing from birth throughout the lifetime, meaning that normal aging, free from dementia, is associated with structural brain changes. This paper reviews recent evidence from magnetic resonance imaging (MRI) studies about age-related changes in the brain. The main conclusions are that (1) the brain shrinks in volume and the ventricular system expands in healthy aging. However, the pattern of changes is highly heterogeneous, with the largest changes seen in the frontal and temporal cortex, and in the putamen, thalamus, and accumbens. With modern approaches to analysis of MRI data, changes in cortical thickness and subcortical volume can be tracked over periods as short as one year, with annual reductions of between 0.5% and 1.0% in most brain areas. (2) The volumetric brain reductions in healthy aging are likely only to a minor extent related to neuronal loss. Rather, shrinkage of neurons, reductions of synaptic spines, and lower numbers of synapses probably account for the reductions in grey matter. In addition, the length of myelinated axons is greatly reduced, up to almost 50%. (3) Reductions in specific cognitive abilities--for instance processing speed, executive functions, and episodic memory--are seen in healthy aging. Such reductions are to a substantial degree mediated by neuroanatomical changes, meaning that between 25% and 100% of the differences between young and old participants in selected cognitive functions can be explained by group differences in structural brain characteristics.

  20. Modeling structural change in spatial system dynamics: A Daisyworld example.

    Science.gov (United States)

    Neuwirth, C; Peck, A; Simonović, S P

    2015-03-01

    System dynamics (SD) is an effective approach for helping reveal the temporal behavior of complex systems. Although there have been recent developments in expanding SD to include systems' spatial dependencies, most applications have been restricted to the simulation of diffusion processes; this is especially true for models on structural change (e.g. LULC modeling). To address this shortcoming, a Python program is proposed to tightly couple SD software to a Geographic Information System (GIS). The approach provides the required capacities for handling bidirectional and synchronized interactions of operations between SD and GIS. In order to illustrate the concept and the techniques proposed for simulating structural changes, a fictitious environment called Daisyworld has been recreated in a spatial system dynamics (SSD) environment. The comparison of spatial and non-spatial simulations emphasizes the importance of considering spatio-temporal feedbacks. Finally, practical applications of structural change models in agriculture and disaster management are proposed.

  1. Structural color change in longhorn beetles Tmesisternus isabellae.

    Science.gov (United States)

    Liu, F; Dong, B Q; Liu, X H; Zheng, Y M; Zi, J

    2009-08-31

    The elytra of longhorn beetles Tmesisternus isabellae show iridescent golden coloration which stems from long and flat scales imbricated densely on the elytral surface. The scales are able to change coloration from golden in the dry state to red in the wet state with water absorption. Structural characterizations revealed that the iridescent coloration of scales originates from a multilayer in the scale interior. Measurements on both water contact angle and chemical composition indicated that scales are hydrophilic. The change in scale coloration to red in the wet state is due to both the swelling of the multilayer period and water infiltration. The unraveled structural color change and its strategy may not only help us get insight into the biological functionality of structural coloration but also inspire the designs of artificial photonic devices.

  2. Shoreline change due to coastal structures of power plants

    International Nuclear Information System (INIS)

    Kang, K. S.; Lee, T. S.; Kim, Y. I.

    2001-01-01

    Characteristics of shoreline change at the coastal area near power plant were analyzed. For a nuclear power plant located in the east coast of Korean peninsula, remote-sensing data, i.e.airborne images and satellite images are acquired and shoreline data were extracted. Recession and davance of shoreline due to coastal structures of powder plant and land reclamation was showed. 1-line numerical shoreline change model was established for simulating the response of shoreline to construction of coastal structures. The model uses curvilinear coordinates that follow the shoreline and is capable of handling the formation of tombolos as well as the growth of salients in the vicinity of coastal structures. The model predicted significant erosion of beach in case breakwaters were extended. Offshore breakwaters were suggested as a countermeasure to shoreline change

  3. Labor mobility, trade and structural change: the Philippine experience.

    Science.gov (United States)

    Abella, M I

    1993-01-01

    "This article addresses three questions: (1) Is the high rate of emigration of labor from the Philippines related to the country's trade policy? (2) Why have migration and accompanying remittances not made much of an impact on the growth and structure of the Philippine economy? (3) Would economic growth and structural change eventually curtail labor emigration? The Philippines' history of labor export and its economic development are contrasted with those of Asian NIEs [newly industrialized economies] which have adopted liberal trade regimes." excerpt

  4. Temperature-induced structural changes in fluorozirconate glasses and liquids

    International Nuclear Information System (INIS)

    Sen, S.; Youngman, R.E.

    2002-01-01

    The atomic structure and its temperature dependence in fluorozirconate glasses and supercooled liquids have been studied with high-resolution and high-temperature 19 F and 23 Na nuclear-magnetic-resonance (NMR) spectroscopy. The 19 F NMR spectra in these glasses show the presence of multiple F environments. Temperature dependence of the 19 F magic-angle-spinning NMR spectra indicates a progressive change in the average F coordination environment in the glass structure, besides motional narrowing due to substantial mobility of F - ions. The observed change in the average 19 F NMR chemical shift is consistent with progressive breaking of the Zr-F-Zr linkages in the glass structure with increasing temperature. The onset of such a change in F speciation is observed at temperatures well below T g . This result is evidence of changes in the average equilibrium structure in an inorganic glass-forming liquid at T g , albeit on a local scale. The 23 Na NMR spectra indicate that the cations in these glasses become significantly mobile only at temperatures T≥T g , which allows for the onset of global structural relaxation and viscous flow

  5. Structural changes during annealing of GaInAsN

    International Nuclear Information System (INIS)

    Kurtz, Sarah; Webb, J.; Gedvilas, L.; Friedman, D.; Geisz, J.; Olson, J.; King, R.; Joslin, D.; Karam, N.

    2001-01-01

    The alloy GaInAsN has great potential as a lower-band-gap material lattice matched to GaAs, but there is little understanding of what causes its poor optoelectronic properties and why these improve with annealing. This study provides information about the structural changes that occur when GaInAsN is annealed. The Fourier transform infrared spectra exhibit two primary features: a triplet at ∼470 cm-1 (Ga--N stretch) and two or three bands at ∼3100 cm-1 (N--H stretch). The change in the Ga--N stretch absorption can be explained if the nitrogen environment is converted from NGa 4 to NInGa 3 after annealing. The N--H stretch is also changed after annealing, implying a second, and unrelated, structural change

  6. Structural change in developing countries: has it decreased gender inequality?

    OpenAIRE

    Rendall, Michelle

    2012-01-01

    This paper examines the evolution of female labor market outcomes from 1987 to 2008 by assessing the role of changing labor demand requirements in four developing countries: Brazil, Mexico, India and Thailand. The results highlight the importance of structural change in reducing gender disparities by decreasing the labor demand for physical attributes. The results show that India, the country with the greatest physical labor requirements, exhibits the largest labor market gender inequality. I...

  7. Frequency effects and structural change – the Afrikaans preterite ...

    African Journals Online (AJOL)

    According to emergent grammar and exemplar theory in cognitive linguistics, the frequency of an item affects its behaviour in terms of structural change. ... While the course of change can also be affected by other factors, such as het (“have”) and had (“had”), and dink (“think”) and gedink/dag/dog (“thought”) show, the data in ...

  8. Structural, optical and electrical properties of novel phase change alloys

    Energy Technology Data Exchange (ETDEWEB)

    Gindner, Sarah; Woda, Michael; Kremers, Stephan; Klein, Michael; Wuttig, Matthias [I. Physikalisches Institut (1A), RWTH Aachen, 52056 Aachen (Germany)

    2008-07-01

    Phase Change Materials (PCM) are Te or Sb containing alloys, which show a remarkable property combination. They possess a very large property contrast, e.g. electrical resistivity and optical reflectivity between the amorphous and crystalline state. At the same time they can be switched between these two states very rapidly on a ns timescale using either a laser or current pulse. Hence they are used in rewriteable optical storage media such as DVDs and Blue-ray disks and are promising candidates for non-volatile electronic memories such as Phase Change Random Access Memory (PCRAM). From a scientific point of view it is important to determine their structural properties. In this study possible new PCM including CuInTe{sub 2} and Ge{sub 3}Sb{sub 6}Te{sub 5} are investigated by a variety of techniques to understand the effect of stoichiometric change upon physical properties. From these techniques the suitability of new materials for phase change application is derived and will be discussed. Temperature dependent resistivity is investigated with the van der Pauw technique. XRD measurements reveal the structural properties of the amorphous and crystalline state. The structural changes causing changes in film thickness and density are measured with X-ray reflectometry. Optical properties (0.02 eV to 5.3 eV) of the PCM are determined by FTIR and ellipsometry measurements.

  9. Structural changes in tetracyanoethylene at high pressures: neutron diffraction study

    International Nuclear Information System (INIS)

    Mukhopadhyay, R.; Chaplot, S.L.

    2002-01-01

    We report on structural changes in monoclinic tetracyanoethylene, C 2 (CN) 4 as studied by in situ high-pressure (0-5 GPa) neutron powder diffraction experiments. Structural parameters were obtained by Rietveld profile refinement of the diffraction pattern up to P=2.5 GPa. Above this pressure the width parameter is found to diverge, indicating pressure-induced disordering at 2.5 GPa. The recovered sample, on release of pressure from 5 GPa, is found to have transformed to a graphite-like amorphous structure. The transformation to a graphite-like material has been verified by an independent high-pressure x-ray diffraction experiment. (author)

  10. Constructional change, paradigmatic structure and the orientation of usage processes

    DEFF Research Database (Denmark)

    Heltoft, Lars

    2014-01-01

    construction from the 18th century to the present, a specialisation process parallel to the one described for English by Colleman & De Clerck (2011), though not identical to it. The semantics of constructions is described in terms of linguistic content, as distinct from conceptual structure, and the linguistic...... stems from one already existing construction type to another. Thus, structural descriptions allow us to orient and interpret usage processes.......This article presents a model analysis of the interplay between structure and usage in the semantic change of constructions, with a focus on the role of content structure in the sense of paradigmatically organised semantic structure. The case at hand the development of the Danish indirect object...

  11. Structural changes of creatine kinase upon substrate binding.

    Science.gov (United States)

    Forstner, M; Kriechbaum, M; Laggner, P; Wallimann, T

    1998-08-01

    Small-angle x-ray scattering was used to investigate structural changes upon binding of individual substrates or a transition state analog complex (TSAC; Mg-ADP, creatine, and KNO3) to creatine kinase (CK) isoenzymes (dimeric muscle-type (M)-CK and octameric mitochondrial (Mi)-CK) and monomeric arginine kinase (AK). Considerable changes in the shape and the size of the molecules occurred upon binding of Mg-nucleotide or TSAC. The radius of gyration of Mi-CK was reduced from 55.6 A (free enzyme) to 48.9 A (enzyme plus Mg-ATP) and to 48.2 A (enzyme plus TSAC). M-CK showed similar changes from 28.0 A (free enzyme) to 25.6 A (enzyme plus Mg-ATP) and to 25.5 A (enzyme plus TSAC). Creatine alone did not lead to significant changes in the radii of gyration, nor did free ATP or ADP. AK also showed a change of the radius of gyration from 21.5 A (free enzyme) to 19.7 A (enzyme plus Mg-ATP), whereas with arginine alone only a minor change could be observed. The primary change in structure as seen with monomeric AK seems to be a Mg-nucleotide-induced domain movement relative to each other, whereas the effect of substrate may be of local order only. In CK, however, additional movements have to be involved.

  12. Combining distributional semantics and structured data to study lexical change

    NARCIS (Netherlands)

    A.E. van Aggelen (Astrid); L. Hollink (Laura); J.R. van Ossenbruggen (Jacco)

    2016-01-01

    textabstractStatistical Natural Language Processing (NLP) techniques allow to quantify lexical semantic change using large text corpora. Wordlevel results of these methods can be hard to analyse in the context of sets of semantically or linguistically related words. On the other hand, structured

  13. Effective Organizational Structures and Processes: Addressing Issues of Change

    Science.gov (United States)

    Andrade, Maureen Snow

    2016-01-01

    This chapter describes organizational structures and processes at the institutional and project levels for the development and support of distance learning initiatives. It addresses environmental and stakeholder issues and explores principles and strategies of effective leadership for change creation and management.

  14. Extinction Partially Reverts Structural Changes Associated with Remote Fear Memory

    Science.gov (United States)

    Vetere, Gisella; Restivo, Leonardo; Novembre, Giovanni; Aceti, Massimiliano; Lumaca, Massimo; Ammassari-Teule, Martine

    2011-01-01

    Structural synaptic changes occur in medial prefrontal cortex circuits during remote memory formation. Whether extinction reverts or further reshapes these circuits is, however, unknown. Here we show that the number and the size of spines were enhanced in anterior cingulate (aCC) and infralimbic (ILC) cortices 36 d following contextual fear…

  15. Combining distributional semantics and structured data to study lexical change

    NARCIS (Netherlands)

    A.E. van Aggelen (Astrid); L. Hollink (Laura); J.R. van Ossenbruggen (Jacco)

    2017-01-01

    textabstractStatistical Natural Language Processing (NLP) techniques allow to quantify lexical semantic change using large text corpora. Wordlevel results of these methods can be hard to analyse in the context of sets of semantically or linguistically related words. On the other hand, structured

  16. Structural changes during the unfolding of Bovine serum albumin in ...

    Indian Academy of Sciences (India)

    The native form of serum albumin is the most important soluble protein in the body plasma. In order to investigate the structural changes of Bovine serum albumin (BSA) during its unfolding in the presence of urea, a small-angle neutron scattering (SANS) study was performed. The scattering curves of dilute solutions of BSA ...

  17. Anatomical changes in the cell-wall structure of Leucaena ...

    African Journals Online (AJOL)

    The structural changes in the cell wall and delignification pattern caused by Trametes versicolor and Trametes hirsuta in the sap wood of Leucaena leucocephala were examined by light and confocal laser scanning microscopy. The in vitro decay test was conducted for 12 weeks. Both species of Trametes used in this study ...

  18. Structural change and agricultural diversification since China’s reforms

    Directory of Open Access Journals (Sweden)

    Lihua Li

    2017-01-01

    Full Text Available Structural change is considered the major engine in fostering a country’s growth. In the agricultural sector, diversification is the commonly used development strategy to increase rural sector’s flexibility, and to respond to improving technologies and market conditions. This study examined agricultural development and transformation during China’s socio-economic reforms. In particular, it empirically investigated whether the change of China’s agricultural structure is consistent with structural change theory and observed outcomes from other countries. The degree of agricultural diversification was quantitatively measured at a regional scale using the Herfindahl index. An underdeveloped province in northwest China was studied to provide insights into the interaction among structural change, agricultural diversification, and implemented development policies. Aggregate-level analyses suggest that China’s agricultural transformation pattern is consistent with those of other developing countries. A specific provincial-level analysis shows that environmentally and economically disadvantaged regions are slower to diversify their economy than better endorsed regions.

  19. Extinction partially reverts structural changes associated with remote fear memory

    DEFF Research Database (Denmark)

    Vetere, Gisella; Restivo, Leonardo; Novembre, Giovanni

    2011-01-01

    Structural synaptic changes occur in medial prefrontal cortex circuits during remote memory formation. Whether extinction reverts or further reshapes these circuits is, however, unknown. Here we show that the number and the size of spines were enhanced in anterior cingulate (aCC) and infralimbic...... the remote memory network, suggesting that the preserved network properties might sustain reactivation of extinguished conditioned fear....

  20. The structural changes in the Mexican coffee sector

    NARCIS (Netherlands)

    Padron, Benigno Rodriguez; Burger, Kees

    2015-01-01

    This paper analyses the structural changes which have been present since the economic clauses of the International Coffee Agreements have no longer been in effect. It studies the elements that modified the coffee policy over time. It also investigates the main characteristics of the entire coffee

  1. Changes in Age Structure and Rural Community Growth.

    Science.gov (United States)

    McGranahan, David A.

    1985-01-01

    Whatever migration patterns evolve, changes in the age structure mean that rural communities in general can expect fairly stable elementary school population, reduced high school population, slower growth in new business and employment, and continued increase in the elderly population. (JHZ)

  2. Understanding and Representing Changing Work Structures and Practices through Art

    Science.gov (United States)

    Wieland, Stacey M. B.

    2018-01-01

    Courses: Organizational Communication, Advanced Organizational Communication, Organizing Work, Management/Organizational History. Objectives: This activity will help students to understand major shifts in the organization of work and creatively represent changing work structures and practices. An optional follow-up assignment is included. A…

  3. Engineering Structures and Environment During this Fast Changing ...

    African Journals Online (AJOL)

    Advancements in science and technology has resulted in an improved human life style and fashionable engineering structures that have allowed modern engineers to pay less attention to how design codes can be modified in respond to growing changes in climatic conditions. This, together with disproportionate use of ...

  4. A structural framework for anomalous change detection and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Lakshman [Los Alamos National Laboratory; Theiler, James P [Los Alamos National Laboratory

    2009-01-01

    We present a spatially adaptive scheme for automatically searching a pair of images of a scene for unusual and interesting changes. Our motivation is to bring into play structural aspects of image features alongside the spectral attributes used for anomalous change detection (ACD). We leverage a small but informative subset of pixels, namely edge pixels of the images, as anchor points of a Delaunay triangulation to jointly decompose the images into a set of triangular regions, called trixels, which are spectrally uniform. Such decomposition helps in image regularization by simple-function approximation on a feature-adaptive grid. Applying ACD to this trixel grid instead of pixels offers several advantages. It allows: (1) edge-preserving smoothing of images, (2) speed-up of spatial computations by significantly reducing the representation of the images, and (3) the easy recovery of structure of the detected anomalous changes by associating anomalous trixels with polygonal image features. The latter facility further enables the application of shape-theoretic criteria and algorithms to characterize the changes and recognize them as interesting or not. This incorporation of spatial information has the potential to filter out some spurious changes, such as due to parallax, shadows, and misregistration, by identifying and filtering out those that are structurally similar and spatially pervasive. Our framework supports the joint spatial and spectral analysis of images, potentially enabling the design of more robust ACD algorithms.

  5. Graph-based structural change detection for rotating machinery monitoring

    Science.gov (United States)

    Lu, Guoliang; Liu, Jie; Yan, Peng

    2018-01-01

    Detection of structural changes is critically important in operational monitoring of a rotating machine. This paper presents a novel framework for this purpose, where a graph model for data modeling is adopted to represent/capture statistical dynamics in machine operations. Meanwhile we develop a numerical method for computing temporal anomalies in the constructed graphs. The martingale-test method is employed for the change detection when making decisions on possible structural changes, where excellent performance is demonstrated outperforming exciting results such as the autoregressive-integrated-moving average (ARIMA) model. Comprehensive experimental results indicate good potentials of the proposed algorithm in various engineering applications. This work is an extension of a recent result (Lu et al., 2017).

  6. Social dilemma structures hidden behind traffic flow with lane changes

    International Nuclear Information System (INIS)

    Tanimoto, Jun; Kukida, Shinji; Hagishima, Aya

    2014-01-01

    Aiming to merge traffic flow analysis with evolutionary game theory, we investigated the question of whether such structures can be formed from frequent lane changes in usual traffic flow without any explicit bottlenecks. In our model system, two classes of driver-agents coexist: C-agents (cooperative strategy) always remain in the lane they are initially assigned, whereas D-agents (defective strategy) try to change lanes to move ahead. In relatively high-density flows, such as the metastable and high-density phases, we found structures that correspond to either n-person prisoner dilemma (n-PD) games or quasi-PD games. In these situations, lane changes by D-agents create heavy traffic jams that reduce social efficiency. (paper)

  7. Inflatable shape changing colonies assembling versatile smart space structures

    Science.gov (United States)

    Sinn, Thomas; Hilbich, Daniel; Vasile, Massimiliano

    2014-11-01

    Various plants have the ability to follow the sun with their flowers or leaves during the course of a day via a mechanism known as heliotropism. This mechanism is characterised by the introduction of pressure gradients between neighbouring motor cells in the plant's stem, enabling the stem to bend. By adapting this bio-inspired mechanism to mechanical systems, a new class of smart structures can be created. The developed overall structure is made up of a number of cellular colonies, each consisting of a central pressure source surrounded by multiple cells. After launch, the cellular arrays are deployed in space and are either preassembled or alternatively are attached together during their release or afterwards. A central pressure source is provided by a high-pressure storage unit with an integrated valve, which provides ingress gas flow to the system; the gas is then routed through the system via a sequence of valve operations and cellular actuations, allowing for any desired shape to be achieved within the constraints of the deployed array geometry. This smart structure consists of a three dimensional adaptable cellular array with fluid controlling Micro Electromechanical Systems (MEMS) components enabling the structure to change its global shape. The proposed MEMS components include microvalves, pressure sensors, mechanical interconnect structures, and electrical routing. This paper will also give an overview of the system architecture and shows the feasibility and shape changing capabilities of the proposed design with multibody dynamic simulations. Example applications of this lightweight shape changing structure include concentrators, mirrors, and communications antennas that are able to dynamically change their focal point, as well as substructures for solar sails that are capable of steering through solar winds by altering the sails' subjected area.

  8. Effect of Population Structure Change on Carbon Emission in China

    Directory of Open Access Journals (Sweden)

    Wen Guo

    2016-03-01

    Full Text Available This paper expanded the Logarithmic Mean Divisia Index (LMDI model through the introduction of urbanization, residents’ consumption, and other factors, and decomposed carbon emission changes in China into carbon emission factor effect, energy intensity effect, consumption inhibitory factor effect, urbanization effect, residents’ consumption effect, and population scale effect, and then explored contribution rates and action mechanisms of the above six factors on change in carbon emissions in China. Then, the effect of population structure change on carbon emission was analyzed by taking 2003–2012 as a sample period, and combining this with the panel data of 30 provinces in China. Results showed that in 2003–2012, total carbon emission increased by 4.2117 billion tons in China. The consumption inhibitory factor effect, urbanization effect, residents’ consumption effect, and population scale effect promoted the increase in carbon emissions, and their contribution ratios were 27.44%, 12.700%, 74.96%, and 5.90%, respectively. However, the influence of carbon emission factor effect (−2.54% and energy intensity effect (−18.46% on carbon emissions were negative. Population urbanization has become the main population factor which affects carbon emission in China. The “Eastern aggregation” phenomenon caused the population scale effect in the eastern area to be significantly higher than in the central and western regions, but the contribution rate of its energy intensity effect (−11.10 million tons was significantly smaller than in the central (−21.61 million tons and western regions (−13.29 million tons, and the carbon emission factor effect in the central area (−3.33 million tons was significantly higher than that in the eastern (−2.00 million tons and western regions (−1.08 million tons. During the sample period, the change in population age structure, population education structure, and population occupation structure

  9. Age structure changes and extraordinary lifespan in wild medfly populations.

    Science.gov (United States)

    Carey, James R; Papadopoulos, Nikos T; Müller, Hans-Georg; Katsoyannos, Byron I; Kouloussis, Nikos A; Wang, Jane-Ling; Wachter, Kenneth; Yu, Wei; Liedo, Pablo

    2008-06-01

    The main purpose of this study was to test the hypotheses that major changes in age structure occur in wild populations of the Mediterranean fruit fly (medfly) and that a substantial fraction of individuals survive to middle age and beyond (> 3-4 weeks). We thus brought reference life tables and deconvolution models to bear on medfly mortality data gathered from a 3-year study of field-captured individuals that were monitored in the laboratory. The average time-to-death of captured females differed between sampling dates by 23.9, 22.7, and 37.0 days in the 2003, 2004, and 2005 field seasons, respectively. These shifts in average times-to-death provided evidence of changes in population age structure. Estimates indicated that middle-aged medflies (> 30 days) were common in the population. A surprise in the study was the extraordinary longevity observed in field-captured medflies. For example, 19 captured females but no reference females survived in the laboratory for 140 days or more, and 6 captured but no reference males survived in the laboratory for 170 days or more. This paper advances the study of aging in the wild by introducing a new method for estimating age structure in insect populations, demonstrating that major changes in age structure occur in field populations of insects, showing that middle-aged individuals are common in the wild, and revealing the extraordinary lifespans of wild-caught individuals due to their early life experience in the field.

  10. Frequency effects and structural change - the Afrikaans preterite

    Directory of Open Access Journals (Sweden)

    Johanita Kirsten

    2016-07-01

    Full Text Available According to emergent grammar and exemplar theory in cognitive linguistics, the frequency of an item affects its behaviour in terms of structural change. In this article, I illustrate how high frequency items, such as preterital modal auxiliaries and copulas in Afrikaans, resist regularising with the rest of the Afrikaans verbal system. Items with a moderately high frequency can resist change for a time, but succumb to it eventually, such as mog (“might” and wis (“knew”. While the course of change can also be affected by other factors, such as het (“have” and had (“had”, and dink (“think” and gedink/dag/dog (“thought” show, the data in diachronic Afrikaans corpora from 1911 to 2010 confirm that high frequency items resist structural change to a large extent, while low frequency items do not. This links with the cognitive representation of language and language processing, and illustrates how the use of language shapes the structure of language.

  11. Conflict transformation, stigma, and HIV-preventive structural change.

    Science.gov (United States)

    Miller, Robin Lin; Reed, Sarah J; Francisco, Vincent T; Ellen, Jonathan M

    2012-06-01

    Over the prior decade, structural change efforts have become an important component of community-based HIV prevention initiatives. However, these efforts may not succeed when structural change initiatives encounter political resistance or invoke conflicting values, which may be likely when changes are intended to benefit a stigmatized population. The current study sought to examine the impact of target population stigma on the ability of 13 community coalitions to achieve structural change objectives. Results indicated that coalitions working on behalf of highly stigmatized populations had to abandon objectives more often than did coalitions working for less stigmatized populations because of external opposition to coalition objectives and resultant internal conflict over goals. Those coalitions that were most successful in meeting external challenges used opposition and conflict as transformative occasions by targeting conflicts directly and attempting to neutralize oppositional groups or turn them into strategic allies; less successful coalitions working on behalf of stigmatized groups struggled to determine an appropriate response to opposition. The role of conflict transformation as a success strategy for working on behalf of stigmatized groups is discussed.

  12. [Labor law issues in hospitals by structural changes and changes in hospital ownership].

    Science.gov (United States)

    Meyer, Peter

    2003-11-01

    The present article deals with the potential impact of structural changes and changes in hospital control or ownership on the employment contracts of the physicians concerned. While taking the applicable jurisdiction into consideration, the author examines the options of assigning new responsibilities or decreasing compensation opportunities, amending or even terminating employment contracts, outsourcing hospital-related services, or allowing physicians in the future to provide these services at their own risk. Furthermore, the article outlines the change in employer in various "change of control" scenarios such as in the case of hospital privatisation.

  13. A proposed structure for an international convention on climate change

    International Nuclear Information System (INIS)

    Nitze, W.A.

    1991-01-01

    In this chapter, the author recommends a framework convention that will stimulate policy changes without expensive emission reductions in the short term. A central task for a climate convention will be to provide the international community with a permanent mechanism for coordinating its efforts to deal with climate change. The convention should go beyond organizational structure to establish a process for updating the parties' understanding of the science and potential impacts of climate change and for building consensus on policy responses. Each party must then be required to prepare and distribute its own national plan for reducing greenhouse gas emissions and for adapting to future change while achieving its development objectives. A set of targets and timetables for the reduction of greenhouse gas reductions is presented

  14. Marsh canopy structure changes and the Deepwater Horizon oil spill

    Science.gov (United States)

    Ramsey, Elijah W.; Rangoonwala, Amina; Jones, Cathleen E.

    2016-01-01

    Marsh canopy structure was mapped yearly from 2009 to 2012 in the Barataria Bay, Louisiana coastal region that was impacted by the 2010 Deepwater Horizon (DWH) oil spill. Based on the previously demonstrated capability of NASA's UAVSAR polarimetric synthetic aperture radar (PolSAR) image data to map Spartina alterniflora marsh canopy structure, structure maps combining the leaf area index (LAI) and leaf angle distribution (LAD, orientation) were constructed for yearly intervals that were directly relatable to the 2010 LAI-LAD classification. The yearly LAI-LAD and LAI difference maps were used to investigate causes for the previously revealed dramatic change in marsh structure from prespill (2009) to postspill (2010, spill cessation), and the occurrence of structure features that exhibited abnormal spatial and temporal patterns. Water level and salinity records showed that freshwater releases used to keep the oil offshore did not cause the rapid growth from 2009 to 2010 in marsh surrounding the inner Bay. Photointerpretation of optical image data determined that interior marsh patches exhibiting rapid change were caused by burns and burn recovery, and that the pattern of 2010 to 2011 LAI decreases in backshore marsh and extending along some tidal channels into the interior marsh were not associated with burns. Instead, the majority of 2010 to 2011 shoreline features aligned with vectors displaying the severity of 2010 shoreline oiling from the DWH spill. Although the association is not conclusive of a causal oil impact, the coexistent pattern is a significant discovery. PolSAR marsh structure mapping provided a unique perspective of marsh biophysical status that enhanced detection of change and monitoring of trends important to management effectiveness.

  15. How do skilled traders change the structure of the market

    Czech Academy of Sciences Publication Activity Database

    Vácha, Lukáš; Baruník, Jozef; Vošvrda, Miloslav

    2012-01-01

    Roč. 23, č. 1 (2012), s. 66-71 ISSN 1057-5219 R&D Projects: GA ČR GAP402/10/0956; GA ČR GP402/08/P207; GA ČR GA402/09/0965 Institutional research plan: CEZ:AV0Z10750506 Institutional support: RVO:67985556 Keywords : Heterogeneous agent model * Market structure * Skilled traders * Hurst exponent Subject RIV: AH - Economics http://library.utia.cas.cz/separaty/2012/E/vacha-how do skilled traders change the structure of the market.pdf

  16. Optical, electrical and structural characterization of novel phase change materials

    Energy Technology Data Exchange (ETDEWEB)

    Herpers, Anja; Woda, Michael; Wuttig, Matthias [1. Physikalisches Institut IA, RWTH Aachen University, Aachen (Germany)

    2009-07-01

    Phase Change Materials (PCM) are alloys, which can be used in a variety of applications in information technology. Information is stored using the transformation of small regions of a thin film between the crystalline and amorphous state. This phase change is accompanied by a remarkable change of properties such as the electrical resistivity and the optical reflectivity. Furthermore the transition between both states is extremely fast at elevated temperatures but negligible at room temperature. This property portfolio is attractive for storage applications. The corresponding materials are already used in rewriteable optical data storage media such as DVD and Blu-Ray-Discs, and are promising candidates for novel non-volatile electronic memory devices such as Phase Change Random Access Memories. In this study the structural, optical and electrical properties of two materials, i.e. Ag{sub 4}In{sub 3}Sb{sub 67}Te{sub 26} and GeSe are investigated. X-Ray diffraction and X-Ray reflection measurements reveal changes in the crystal structure and the film density upon crystallization. DSC measurements provide the crystallization temperature. The optical properties in an energy range of 0.025-5.3 eV are determined combining ellipsometry and FTIR experiments. Sheet resistance measurements in the van-der-Pauw-geometry enable the measurement of the electrical properties between 300 and 600 K.

  17. Structural Changes of Creatine Kinase upon Substrate Binding

    OpenAIRE

    Forstner, Michael; Kriechbaum, Manfred; Laggner, Peter; Wallimann, Theo

    1998-01-01

    Small-angle x-ray scattering was used to investigate structural changes upon binding of individual substrates or a transition state analog complex (TSAC; Mg-ADP, creatine, and KNO3) to creatine kinase (CK) isoenzymes (dimeric muscle-type (M)-CK and octameric mitochondrial (Mi)-CK) and monomeric arginine kinase (AK). Considerable changes in the shape and the size of the molecules occurred upon binding of Mg-nucleotide or TSAC. The radius of gyration of Mi-CK was reduced from 55.6 A (free enzym...

  18. CERN's new Career Structure Main Changes in a Nutshell

    CERN Multimedia

    2001-01-01

    All Staff Members will have received an official notification of their position in the new career path structure, with effect from 1 September 2001. A Weekly Bulletin announcement two weeks ago (Bulletin 33/2001) referred to documents and contacts for individual or general information, notably via the HR Division Web site (see below). The present article summarises the main changes between the MOAS and the MAPS (Merit Advancement and Promotion Scheme). The aim of MAPS is to make the career structure more dynamic, while retaining positive elements of the MOAS scheme, notably an annual interview and performance assessment process. The main changes are: - Career reviews including salary band promotion at several stages in a person's career replace the previous automatic grade-to-grade progression within a career path. - Speeds of advancement can be modulated to a greater extent. - The exceptional advancement zone is re-designed. - Premiums or allowances linked to performance, responsibility, and specific labou...

  19. Structural Changes are More Important than Compositional Changes in Driving Biomass Loss in Ugandan Forest Fragments

    Directory of Open Access Journals (Sweden)

    C. Bulafu

    2014-01-01

    Full Text Available Aboveground biomass (AGB contained in privately-owned forests is less frequently measured than in forest reserves despite their greater likelihood of degradation. We demonstrate how density changes in contrast to species compositional changes have driven AGB changes in privately-owned fragments in Uganda over two decades. Data on tree assemblages in fragments were obtained by re-sampling a 1990 dataset in 2010 and AGB estimated using generalised allometric equation that incorporates diameter at breast height (DBH and species-specific wood density. AGB were highly variable between fragments and over time. Structural changes contributed a higher proportion of change in AGB than species compositional changes in all forests. Non-pioneer species constituted over 50% of AGB in reserve forest, in contrast to private forests where pioneer species dominated. Our study demonstrates the potential of private forests to hold comparable AGB to plantation. Reduction in exploitation pressure is required if fragments are to mitigate carbon emissions.

  20. Strain-induced changes to the electronic structure of germanium

    KAUST Repository

    Tahini, H. A.

    2012-04-17

    Density functional theory calculations (DFT) are used to investigate the strain-induced changes to the electronic structure of biaxially strained (parallel to the (001), (110) and (111) planes) and uniaxially strained (along the [001], [110] and [111] directions) germanium (Ge). It is calculated that a moderate uniaxial strain parallel to the [111] direction can efficiently transform Ge to a direct bandgap material with a bandgap energy useful for technological applications. © 2012 IOP Publishing Ltd.

  1. Change in Family Structure and Rates of Violent Juvenile Delinquency

    OpenAIRE

    Fry, Jeannie A

    2010-01-01

    This paper addresses the question: Have the changes in family structure in the U.S. become a catalyst for juvenile delinquency? For this research, I use existing statistics for my three independent variables: divorce rates, rate of working mothers with children under age 18, percent female-headed households. My dependent variable, juvenile violent crime rates, is measured using data from the Office of Juvenile Justice and Delinquency Prevention. My control variables consist of the followin...

  2. Microgravity changes in heart structure and cyclic-AMP metabolism

    Science.gov (United States)

    Philpott, D. E.; Fine, A.; Kato, K.; Egnor, R.; Cheng, L.

    1985-01-01

    The effects of microgravity on cardiac ultrastructure and cyclic AMP metabolism in tissues of rats flown on Spacelab 3 are reported. Light and electron microscope studies of cell structure, measurements of low and high Km phosphodiesterase activity, cyclic AMP-dependent protein kinase activity, and regulatory subunit compartmentation show significant deviations in flight animals when compared to ground controls. The results indicate that some changes have occurred in cellular responses associated with catecholamine receptor interactions and intracellular signal processing.

  3. Strain-induced changes to the electronic structure of germanium.

    Science.gov (United States)

    Tahini, H; Chroneos, A; Grimes, R W; Schwingenschlögl, U; Dimoulas, A

    2012-05-16

    Density functional theory calculations (DFT) are used to investigate the strain-induced changes to the electronic structure of biaxially strained (parallel to the (001), (110) and (111) planes) and uniaxially strained (along the [001], [110] and [111] directions) germanium (Ge). It is calculated that a moderate uniaxial strain parallel to the [111] direction can efficiently transform Ge to a direct bandgap material with a bandgap energy useful for technological applications.

  4. Trade, Reform and Structural Change in South Korea

    OpenAIRE

    Betts, Caroline; Giri, Rahul; Verma, Rubina

    2017-01-01

    We develop a two country, three-sector model to quantify the effects of Korean trade policies for structural change from 1963 through 2000. The model features non-homothetic preferences, Armington trade, proportional import tariffs and export subsidies, and is calibrated to match sectoral value added data on Korean production and trade. Korea’s tariff liberalization increased imports and trade, especially agricultural imports, accelerating de-agriculturalization and intensifying industrializa...

  5. Change in fish community structure in the Barents Sea.

    Directory of Open Access Journals (Sweden)

    Michaela Aschan

    Full Text Available Change in oceanographic conditions causes structural alterations in marine fish communities, but this effect may go undetected as most monitoring programs until recently mainly have focused on oceanography and commercial species rather than on whole ecosystems. In this paper, the objective is to describe the spatial and temporal changes in the Barents Sea fish community in the period 1992-2004 while taking into consideration the observed abundance and biodiversity patterns for all 82 observed fish species. We found that the spatial structure of the Barents Sea fish community was determined by abiotic factors such as temperature and depth. The observed species clustered into a deep assemblage, a warm water southern assemblage, both associated with Atlantic water, and a cold water north-eastern assemblage associated with mixed water. The latitude of the cold water NE and warm water S assemblages varied from year to year, but no obvious northward migration was observed over time. In the period 1996-1999 we observed a significant reduction in total fish biomass, abundance, mean fish weight, and a change in community structure including an increase in the pelagic/demersal ratio. This change in community structure is probably due to extremely cold conditions in 1996 impacting on a fish community exposed to historically high fishing rates. After 1999 the fish community variables such as biomass, abundance, mean weight, P/D ratio as well as community composition did not return to levels of the early 90s, although fishing pressure and climatic conditions returned to earlier levels.

  6. Ongoing Change in the Structure of Part-Time Employment

    OpenAIRE

    Karl Brenke

    2011-01-01

    The prominence of part-time employment has dramatically increased both in Germany and across Europe. Germany has experienced above- average growth and currently the prevalence of part-time employment there also exceeds the EU average. Evidently, this involves fundamental structural change as part-time employment has increased regardless of economic trends. Although part-time positions often still entail predominantly low-skilled work, the number of mediumskilled or highly qualified employees ...

  7. Structural Change and Economic Development in China and India

    Directory of Open Access Journals (Sweden)

    Vittorio Valli

    2009-06-01

    Full Text Available The comparison of the periods of rapid economic growth in China since 1978 and India since 1992 markedly show different patterns of development and structural change. However, both countries experienced some advantages of "relative economic backwardness" and some aspects of the "fordist model of growth". China had an anticipated and deeper structural change, spurred mainly by economic reforms and the growth of the internal market in the 1980s, and, since the mid-1990s, by a very rapid penetration of its industrial products in the world market. However, a substantial part of China's exports in medium and high tech sectors are due to joint-ventures with foreign multinationals. India had a more balanced structural change and a slower insertion in the world market, although some sectors, such as software, steel, automotive and pharmaceuticals are recently increasing their share in the world markets. Owing to the huge number of micro-enterprises and the great size of the informal sector, India benefited much less than China from the economies of scale and from the third wave of the "fordist model of growth". Both countries, but in particular China, experienced negative externalities of this recent phase of rapid growth, such as higher inequalities, pollution and urban congestion.

  8. Family Structure Changes and Children's Health, Behavior, and Educational Outcomes

    DEFF Research Database (Denmark)

    Rasmussen, Astrid Würtz

    More and more children do not grow up in traditional nuclear families. Instead, they grow up in single-parent households or in families with a step-parent. Hence, it is important to improve our understanding of the impact of "shocks" in family structure due to parental relationship dissolution...... on children. In this study I empirically test whether children are traumatized both in the short and the long run by shocks in the family structure during childhood. I focus on educational, behavioral, and health outcomes. A population sample of Danish children born in January to May 1985 is used...... for the analysis. The empirical cross-sectional analysis indicates a negative relation between the number of family structure changes and children.s health, behavior, and educational outcomes. These results are con.rmed by a differences-in-differences analysis of health outcomes. This suggests...

  9. Structure change of soda-silicate glass by mechanical milling

    International Nuclear Information System (INIS)

    Iwao, M; Okuno, M

    2010-01-01

    Structure change of ground soda-silicate glass (SiO 2 -Na 2 O binary systems) was investigated using X-ray diffraction (XRD) and infrared spectroscopy. The measurement results were discussed comparison to that of SiO 2 glass. With increasing Na 2 O concentrations, the XRD intensity around 2θ = 22 0 decreased and the intensity around 32 0 increased. The intensity around 22 0 and 32 0 maybe attributed to SiO 2 glass structure unit and soda-silicate glass unit, respectively. The peaks of Na 2 CO 3 crystal for 2SiO 2 -Na 2 O glass were observed with increasing milling time. This crystallization was suggested that Na + ion on 2SiO 2 -Na 2 O glass surface connected CO 2 in air. The intensity around 22 0 and 32 0 decreased and the intensity around 30 0 increased with increasing milling time. These may indicate that SiO 2 glass structure unit and soda-silicate glass structure unit were mixed by milling. In addition, IR absorption band near v = 1100 cm -1 was separated to two bands near 940 cm -1 and 1070 cm -1 with increasing Na 2 O concentrations. The band near 940 cm -1 decreased and the band near 1070 cm -1 increased with increasing milling time. These spectra changes were suggested due to decrease of Na 2 O concentrations in 2SiO 2 -Na 2 O glass with Na 2 CO 3 crystallization.

  10. Altered structural brain changes and neurocognitive performance in pediatric HIV

    Directory of Open Access Journals (Sweden)

    Santosh K. Yadav

    2017-01-01

    Full Text Available Pediatric HIV patients often suffer with neurodevelopmental delay and subsequently cognitive impairment. While tissue injury in cortical and subcortical regions in the brain of adult HIV patients has been well reported there is sparse knowledge about these changes in perinatally HIV infected pediatric patients. We analyzed cortical thickness, subcortical volume, structural connectivity, and neurocognitive functions in pediatric HIV patients and compared with those of pediatric healthy controls. With informed consent, 34 perinatally infected pediatric HIV patients and 32 age and gender matched pediatric healthy controls underwent neurocognitive assessment and brain magnetic resonance imaging (MRI on a 3 T clinical scanner. Altered cortical thickness, subcortical volumes, and abnormal neuropsychological test scores were observed in pediatric HIV patients. The structural network connectivity analysis depicted lower connection strengths, lower clustering coefficients, and higher path length in pediatric HIV patients than healthy controls. The network betweenness and network hubs in cortico-limbic regions were distorted in pediatric HIV patients. The findings suggest that altered cortical and subcortical structures and regional brain connectivity in pediatric HIV patients may contribute to deficits in their neurocognitive functions. Further, longitudinal studies are required for better understanding of the effect of HIV pathogenesis on brain structural changes throughout the brain development process under standard ART treatment.

  11. Structural changes of polytetrafluoroethylene during irradiation in oxygen

    International Nuclear Information System (INIS)

    Liu, Shuling; Fu, Congli; Gu, Aiqun; Yu, Zili

    2015-01-01

    To study the effect of irradiation on PTFE structure and prepare modified PTFE micropowder, PTFE was irradiated with dose up to 4 MGy in oxygen at room temperature. The structures of both irradiated and unirradiated PTFE samples were comparatively characterized by IR, XPS, Raman spectra and XRD measurement. The results showed that new groups of acyl fluoride (COF), carboxylic acid (COOH) and trifluoromethyl (CF 3 ) were formed under heavy radiation exposure in oxygen. In addition, the expansion of crystallite size or crystal lattice was first reported for the irradiated PTFE. The formation of new chemical groups and the expansion of crystallite size were elucidated by structural changes occurring in irradiation. - Highlights: • The structural change of PTFE irradiated in O 2 is different from that in vacuum. • The double bond is not found in PTFE after irradiation in oxygen. • The new groups like COF, COOH and CF 3 are formed in PTFE after irradiation. • The expansion of crystallite size is observed in the irradiated PTFE

  12. Aging effects on regional brain structural changes in schizophrenia.

    Science.gov (United States)

    Nenadić, Igor; Sauer, Heinrich; Smesny, Stefan; Gaser, Christian

    2012-06-01

    Although mostly conceptualized as a neurodevelopmental disorder, there is an increasing interest in progressive changes of cognitive deficits and brain structure and function in schizophrenia across the life span. In this study, we investigated age-related changes in regional gray matter using voxel-based morphometry in a sample of 99 patients (age range 18-65 years) with Diagnostic and Statistical Manual of Mental Disorders-IV schizophrenia and 113 healthy controls (age range 19-59 years) using a cross-sectional design. We found steeper age-related decline in gray matter in patients in a cluster comprising the left superior temporal cortex and adjacent inferior parietal lobule. We then divided the schizophrenia sample in 3 subgroups based on a 3-factor model of psychopathology ratings. Age-related changes were markedly different in each of the 3 subgroups (compared with healthy controls). While patients with predominantly paranoid symptoms showed stronger age-related progression in the left superior temporal cortex and right inferior frontal gyrus, those of the disorganized subgroup had stronger gray matter loss in the left lateral cerebellum, while the predominantly negative subgroup showed minor effects in the left superior temporal gyrus. Our findings show that differences in brain structural changes associated with aging diverge between schizophrenia patients and healthy subjects and that different subgroups within a patient sample might be at higher risk of age-related regional gray matter loss.

  13. Ion induced changes in the structure of bordered pit membranes

    Directory of Open Access Journals (Sweden)

    Jinkee eLee

    2012-03-01

    Full Text Available Xylem hydraulic resistance varies with ion concentration in sap solution. It is assumed that this variation in resistance results from hydrogel like properties of pectins located in bordered pit membranes separating adjacent vessels. Although kinetics of the resistance change suggests swelling/deswelling behavior of the pectins, there is no direct evidence of this activity. In this report we provide evidence of structural changes in bordered pit membranes responding to variation in ionic concentration of solute around it using atomic force microscopy (AFM. AFM revealed bordered pit membranes as relatively smooth, soft and lacking any sharp edges surface when submerged in de-ionized water, in contrast to pictures from scanning electron microscope (SEM or AFM performed on air dry material. Exposure of the bordered pit membranes to 50 mM KCl solution resulted in significant changes in both surface physical properties with and elevation features as bordered pit membrane became harder, with visible edges of fibers and collapsed, while no change in porosity was observed. Analysis suggests a need for a major shift in our understanding to the physical bases of variable xylem resistance from change in porosity to change in pathway length. Findings support the role of actuating properties of hybrid hydrogel-cellulose materials in water redistribution and embolism resistance.

  14. Structural changes in the rural planting areas of Belgrade region

    Directory of Open Access Journals (Sweden)

    Sibinović Mikica

    2012-01-01

    Full Text Available Socio-economic development of the Belgrade region significantly affects the direction of the change of planting areas use. The increase in urban areas has adversely affected the direction of agricultural land use. Dynamics of change is significantly due to high production costs (high land prices and expensive labor force gives rise to the high price of the product on the market, there is a constant "pressure" of urban areas to arable land, increasing the risk of "loss" of agricultural holdings; increased environmental pollution due to the concentration of industrial plants or road construction. The aim of this study was to investigate the characteristics of structural changes in sowing area in the period from 1991 to 2011. [Projekat Ministarstva nauke Republike Srbije, br. 176017

  15. Structural change in the petroleum activities; Strukturendringer i petroleumsvirksomheten

    Energy Technology Data Exchange (ETDEWEB)

    2009-07-01

    The report is twofold. First it is described a reference situation for the petroleum industry based on qualitative and quantitative parameters. The purpose of this section is to form a basis of a future observation can be assessed. Then referred the views and reviews a wide range of stake holders in the industry has about how the structures in the petroleum industry will evolve in the years ahead. The views and reviews that are reproduced are from players in the petroleum industry itself, represented by 48 companies and organizations, and are not the views or opinions of Ministry of Petroleum and Energy. Participants' attention is mainly focused on how StatoilHydro will affect the industry, but it is also a general perception that there are many other factors that are just as important for how the industry will evolve in the long term. Participants' views will help to identify trends that may affect the player image. The project is not intended to constitute a strategy for or how to accommodate structural changes in the petroleum industry. The report discusses not systematically the structural changes that will be positive or negative for the industry and proposes no measures that will affect them. In Chapter 5, however, rendered what the various players in the interview rounds have proposed measures to counter the various structural changes. Finally touches the report not the significance of structural changes in the industry may have on health, safety and environment (HSE) in activity. The views and reviews from the players were passed in 2008, before the problems in the financial industry gained a considerable extent. Data and forecasts are also prepared during this period. Reviews in the report were accordingly given before one learned about the extent of the economic development and are not revised in the afterwards. Ministry of Petroleum and Energy will in the years ahead have to have a continuous attention to the issues described in this report. It

  16. Structural changes in gluten protein structure after addition of emulsifier. A Raman spectroscopy study

    Science.gov (United States)

    Ferrer, Evelina G.; Gómez, Analía V.; Añón, María C.; Puppo, María C.

    2011-06-01

    Food protein product, gluten protein, was chemically modified by varying levels of sodium stearoyl lactylate (SSL); and the extent of modifications (secondary and tertiary structures) of this protein was analyzed by using Raman spectroscopy. Analysis of the Amide I band showed an increase in its intensity mainly after the addition of the 0.25% of SSL to wheat flour to produced modified gluten protein, pointing the formation of a more ordered structure. Side chain vibrations also confirmed the observed changes.

  17. Climate change effects on soil microarthropod abundance and community structure

    Energy Technology Data Exchange (ETDEWEB)

    Kardol, Paul [ORNL; Reynolds, W. Nicholas [University of Tennessee, Knoxville (UTK); Norby, Richard J [ORNL; Classen, Aimee T [University of Tennessee, Knoxville (UTK)

    2011-01-01

    Long-term ecosystem responses to climate change strongly depend on how the soil subsystem and its inhabitants respond to these perturbations. Using open-top chambers, we studied the response of soil microarthropods to single and combined effects of ambient and elevated atmospheric [CO{sub 2}], ambient and elevated temperatures and changes in precipitation in constructed old-fields in Tennessee, USA. Microarthropods were assessed five years after treatments were initiated and samples were collected in both November and June. Across treatments, mites and collembola were the most dominant microarthropod groups collected. We did not detect any treatment effects on microarthropod abundance. In November, but not in June, microarthropod richness, however, was affected by the climate change treatments. In November, total microarthropod richness was lower in dry than in wet treatments, and in ambient temperature treatments, richness was higher under elevated [CO{sub 2}] than under ambient [CO{sub 2}]. Differential responses of individual taxa to the climate change treatments resulted in shifts in community composition. In general, the precipitation and warming treatments explained most of the variation in community composition. Across treatments, we found that collembola abundance and richness were positively related to soil moisture content, and that negative relationships between collembola abundance and richness and soil temperature could be explained by temperature-related shifts in soil moisture content. Our data demonstrate how simultaneously acting climate change factors can affect the structure of soil microarthropod communities in old-field ecosystems. Overall, changes in soil moisture content, either as direct effect of changes in precipitation or as indirect effect of warming or elevated [CO{sub 2}], had a larger impact on microarthropod communities than did the direct effects of the warming and elevated [CO{sub 2}] treatments. Moisture-induced shifts in soil

  18. MRI assessment of whole-brain structural changes in aging.

    Science.gov (United States)

    Guo, Hui; Siu, William; D'Arcy, Ryan Cn; Black, Sandra E; Grajauskas, Lukas A; Singh, Sonia; Zhang, Yunting; Rockwood, Kenneth; Song, Xiaowei

    2017-01-01

    One of the central features of brain aging is the accumulation of multiple age-related structural changes, which occur heterogeneously in individuals and can have immediate or potential clinical consequences. Each of these deficits can coexist and interact, producing both independent and additive impacts on brain health. Many of the changes can be visualized using MRI. To collectively assess whole-brain structural changes, the MRI-based Brain Atrophy and Lesion Index (BALI) has been developed. In this study, we validate this whole-brain health assessment approach using several clinical MRI examinations. Data came from three independent studies: the Alzheimer's Disease Neuroimaging Initiative Phase II (n=950; women =47.9%; age =72.7±7.4 years); the National Alzheimer's Coordinating Center (n=722; women =55.1%; age =72.7±9.9 years); and the Tianjin Medical University General Hospital Research database on older adults (n=170; women =60.0%; age =62.9±9.3 years). The 3.0-Tesla MRI scans were evaluated using the BALI rating scheme on the basis of T1-weighted (T1WI), T2-weighted (T2WI), T2-weighted fluid-attenuated inversion recovery (T2-FLAIR), and T2*-weighted gradient-recalled echo (T2*GRE) images. Atrophy and lesion changes were commonly seen in each MRI test. The BALI scores based on different sequences were highly correlated (Spearman r 2 >0.69; P age ( r 2 >0.29; P 26.48, P aging and dementia-related decline of structural brain health. Inclusion of additional MRI tests increased lesion differentiation. Further research is to integrate MRI tests for a clinical tool to aid the diagnosis and intervention of brain aging.

  19. White matter structure changes as adults learn a second language.

    Science.gov (United States)

    Schlegel, Alexander A; Rudelson, Justin J; Tse, Peter U

    2012-08-01

    Traditional models hold that the plastic reorganization of brain structures occurs mainly during childhood and adolescence, leaving adults with limited means to learn new knowledge and skills. Research within the last decade has begun to overturn this belief, documenting changes in the brain's gray and white matter as healthy adults learn simple motor and cognitive skills [Lövdén, M., Bodammer, N. C., Kühn, S., Kaufmann, J., Schütze, H., Tempelmann, C., et al. Experience-dependent plasticity of white-matter microstructure extends into old age. Neuropsychologia, 48, 3878-3883, 2010; Taubert, M., Draganski, B., Anwander, A., Müller, K., Horstmann, A., Villringer, A., et al. Dynamic properties of human brain structure: Learning-related changes in cortical areas and associated fiber connections. The Journal of Neuroscience, 30, 11670-11677, 2010; Scholz, J., Klein, M. C., Behrens, T. E. J., & Johansen-Berg, H. Training induces changes in white-matter architecture. Nature Neuroscience, 12, 1370-1371, 2009; Draganski, B., Gaser, C., Busch, V., Schuirer, G., Bogdahn, U., & May, A. Changes in grey matter induced by training. Nature, 427, 311-312, 2004]. Although the significance of these changes is not fully understood, they reveal a brain that remains plastic well beyond early developmental periods. Here we investigate the role of adult structural plasticity in the complex, long-term learning process of foreign language acquisition. We collected monthly diffusion tensor imaging scans of 11 English speakers who took a 9-month intensive course in written and spoken Modern Standard Chinese as well as from 16 control participants who did not study a language. We show that white matter reorganizes progressively across multiple sites as adults study a new language. Language learners exhibited progressive changes in white matter tracts associated with traditional left hemisphere language areas and their right hemisphere analogs. Surprisingly, the most significant changes

  20. Classification of RNA structure change by 'gazing' at experimental data.

    Science.gov (United States)

    Woods, Chanin Tolson; Laederach, Alain

    2017-06-01

    Mutations (or Single Nucleotide Variants) in folded RiboNucleic Acid structures that cause local or global conformational change are riboSNitches. Predicting riboSNitches is challenging, as it requires making two, albeit related, structure predictions. The data most often used to experimentally validate riboSNitch predictions is Selective 2' Hydroxyl Acylation by Primer Extension, or SHAPE. Experimentally establishing a riboSNitch requires the quantitative comparison of two SHAPE traces: wild-type (WT) and mutant. Historically, SHAPE data was collected on electropherograms and change in structure was evaluated by 'gel gazing.' SHAPE data is now routinely collected with next generation sequencing and/or capillary sequencers. We aim to establish a classifier capable of simulating human 'gazing' by identifying features of the SHAPE profile that human experts agree 'looks' like a riboSNitch. We find strong quantitative agreement between experts when RNA scientists 'gaze' at SHAPE data and identify riboSNitches. We identify dynamic time warping and seven other features predictive of the human consensus. The classSNitch classifier reported here accurately reproduces human consensus for 167 mutant/WT comparisons with an Area Under the Curve (AUC) above 0.8. When we analyze 2019 mutant traces for 17 different RNAs, we find that features of the WT SHAPE reactivity allow us to improve thermodynamic structure predictions of riboSNitches. This is significant, as accurate RNA structural analysis and prediction is likely to become an important aspect of precision medicine. The classSNitch R package is freely available at http://classsnitch.r-forge.r-project.org . alain@email.unc.edu. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press.

  1. Strain Concentration at Structural Discontinuities and Its Prediction Based on Characteristics of Compliance Change in Structures

    Science.gov (United States)

    Kasahara, Naoto

    Elevated temperature structural design codes pay attention to strain concentration at structural discontinuities due to creep and plasticity, since it causes an increase in creep-fatigue damage of materials. One of the difficulties in predicting strain concentration is its dependence on the magnitude of loading, the constitutive equations, and the duration of loading. In this study, the author investigated the fundamental mechanism of strain concentration and its main factors. The results revealed that strain concentration is caused by strain redistribution between elastic and inelastic regions, which can be quantified by the characteristics of structural compliance. The characteristics of structural compliance are controlled by elastic region in structures and are insensitive to constitutive equations. It means that inelastic analysis can be easily applied to obtain compliance characteristics. By utilizing this fact, a simplified inelastic analysis method was proposed based on the characteristics of compliance change for the prediction of strain concentration.

  2. Evaluation of soil structural changes through macroscopic and microscopic measurement

    Science.gov (United States)

    Parvin, Nargish; Chélin, Marie; Hiel, Marie-Pierre; Barbieux, Sophie; Bodson, Bernard; Garré, Sarah; Colinet, Gilles; Degré, Aurore

    2015-04-01

    The heterogeneity of soil structure and pore size distribution are highly influenced by external factors like tillage systems and other agricultural management practices. However, changes in soil hydrodynamic behavior are not fully understood and are still under research. Also, researchers have explained the impact of tillage practices on soil hydraulic properties related to pore size distribution, connectivity and orientation are involved but the characterization of these modifications and consequences remains a challenge. Furthermore, the relation between macroscopic measurements and microscopic investigation of the soil structure remains scarce. Recently, X-ray tomography (X- μCT) has been used in order to characterize changes in soil pore size distribution in various contexts and the method is able to link microtomography information to hydrodynamic measurement. In our study, X-μCT has been used in order to characterize changes in soil pore system. Since, tomography does not count most of the micropores, Richards' pressure plate and evaporation method was also combined to get complete range of pore size distribution. We found good match between evaporation data with X-μCT at the macropore scale and evaporation data with pressure plate method at micropore scale. X-μCT data refines retention and hydraulic curves near saturation where Richards' data alone can lead to numerous sets of fitted parameters. On the otherhand, evaporation data (Hyprop apparatus ©) provide comparable datasets with X-μCT. Combining micro and macroscopic measurements allows us to validate X-μCT information, which is otherwise not so obvious.

  3. Structural and Functional Changes With the Aging Kidney.

    Science.gov (United States)

    Denic, Aleksandar; Glassock, Richard J; Rule, Andrew D

    2016-01-01

    Senescence or normal physiologic aging portrays the expected age-related changes in the kidney as compared to a disease that occurs in some but not all individuals. The microanatomical structural changes of the kidney with older age include a decreased number of functional glomeruli from an increased prevalence of nephrosclerosis (arteriosclerosis, glomerulosclerosis, and tubular atrophy with interstitial fibrosis), and to some extent, compensatory hypertrophy of remaining nephrons. Among the macroanatomical structural changes, older age associates with smaller cortical volume, larger medullary volume until middle age, and larger and more numerous kidney cysts. Among carefully screened healthy kidney donors, glomerular filtration rate (GFR) declines at a rate of 6.3 mL/min/1.73 m(2) per decade. There is reason to be concerned that the elderly are being misdiagnosed with CKD. Besides this expected kidney function decline, the lowest risk of mortality is at a GFR of ≥75 mL/min/1.73 m(2) for age kidney functional reserve when they do actually develop CKD, and they are at higher risk for acute kidney injury. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  4. The changes of ADI structure during high temperature annealing

    Directory of Open Access Journals (Sweden)

    A. Krzyńska

    2010-01-01

    Full Text Available The results of structure investigations of ADI during it was annealing at elevated temperature are presented. Ductile iron austempered at temperature 325oC was then isothermally annealed 360 minutes at temperature 400, 450, 500 and 550oC. The structure investigations showed that annealing at these temperatures caused substantial structure changes and thus essential hardness decrease, which is most useful property of ADI from point of view its practical application. Degradation advance of the structure depends mainly on annealing temperature, less on the time of the heat treatment. It was concluded that high temperature annealing caused precipitation of Fe3C type carbides, which morphology and distribution depend on temperature. In case of 400oC annealing the carbides precipitates inside bainitic ferrite lath in specific crystallographic planes and partly at the grain boundaries. The annealing at the temperature 550oC caused disappearing of characteristic for ADI needle or lath – like morphology, which is replaced with equiaxed grains. In this case Fe3C carbides take the form very fine precipitates with spheroidal geometry.

  5. Fiscal reaction under endogenous structural changes in Brazil

    Directory of Open Access Journals (Sweden)

    Andrei G. Simonassi

    2014-01-01

    Full Text Available Regarding the importance of fiscal policy in smoothing the impact of shocks such as the international financial and economic crises, the paper analyzes the sustainability of the Brazilian fiscal policy by taking into consideration the possibility of multiple endogenous structural breaks on the coefficients of government reaction function. From monthly data in the period 1991–2008, tests on the reliable estimates dictate the occurrence of structural change in May 1994, and another in February 2003. There has been a situation of fiscal solvency in Brazil, but only from May 1994 the hitherto innocuous actions of government to formulate policies on public debt turn out to be significant, as it rose twofold after February 2003. This reinforces the existence of a more flexible alternative to implement strategic policy in Brazil, if an eventual alternative for increasing public spending is a way of hindering the effects of international financial crises without compromising the fiscal targets.

  6. Mind-Reading Ability and Structural Connectivity Changes in Aging.

    Science.gov (United States)

    Cabinio, Monia; Rossetto, Federica; Blasi, Valeria; Savazzi, Federica; Castelli, Ilaria; Massaro, Davide; Valle, Annalisa; Nemni, Raffaello; Clerici, Mario; Marchetti, Antonella; Baglio, Francesca

    2015-01-01

    The Mind-Reading ability through the eyes is an important component of the affective Theory of Mind (ToM), which allows people to infer the other's mental state from the eye gaze. The aim of the present study was to investigate to which extent age-associated structural brain changes impact this ability and to determine if this association is related to executive functions in elderly subjects. For this purpose, Magnetic Resonance Imaging was used to determine both gray matter and white matter (WM) areas associated with aging. The resulting areas have been included in a subsequent correlation analysis to detect the brain regions whose structure was associated with the Mind-Reading ability through the eyes, assessed with the Italian version of the "Reading the Mind in the Eyes" (RME) test, in a sample of 36 healthy subjects ranging from 24 to 79 years of age. The analysis resulted in three important findings: (1) the performance to the RME test is relatively stable across the decades 20-70 (despite a slight decrease of this ability with aging) and independent from executive functions; (2) structural brain imaging demonstrated the involvement of a great number of cortical ToM areas for the execution of the RME test: the bilateral precentral gyrus, the bilateral posterior insula, the left superior temporal gyrus and the left inferior frontal gyrus, which also showed a significant volume decrease with age; (3) an age and task-related decline in WM connectivity on left fronto-temporal portion of the brain. Our results confirm the age-related structural modifications of the brain and show that these changes have an influence on the Mind-Reading ability through the eyes.

  7. Mind-Reading ability and structural connectivity changes in aging

    Directory of Open Access Journals (Sweden)

    Monia eCabinio

    2015-11-01

    Full Text Available The Mind-Reading ability through the eyes is an important component of the affective Theory of Mind (ToM, which allows people to infer the other’s mental state from the eye gaze. The aim of the present study was to investigate to which extent age-associated structural brain changes impact this ability and to determine if this association is related to executive functions in elderly subjects. For this purpose, Magnetic Resonance Imaging was used to determine both gray matter and white matter areas associated with aging. The resulting areas have been included in a subsequent correlation analysis to detect the brain regions whose structure was associated with the Mind-Reading ability through the eyes, assessed with the Italian version of the Reading the Mind in the Eyes (RME test, in a sample of 36 healthy subjects ranging from 24 to 79 years of age. The analysis resulted in three important findings: 1 the performance to the RME test is relatively stable across the decades 20-70 (despite a slight decrease of this ability with aging and independent from executive functions; 2 structural brain imaging demonstrated the involvement of a great number of cortical ToM areas for the execution of the RME test: the bilateral precentral gyrus, the bilateral posterior insula, the left superior temporal gyrus and the left inferior frontal gyrus, which also showed a significant volume decrease with age; 3 an age and task-related decline in white matter connectivity on left fronto-temporal portion of the brain. Our results confirm the age-related structural modifications of the brain and show that these changes have an influence on the Mind-Reading ability through the eyes.

  8. Extinction partially reverts structural changes associated with remote fear memory

    DEFF Research Database (Denmark)

    Vetere, Gisella; Restivo, Leonardo; Novembre, Giovanni

    2011-01-01

    Structural synaptic changes occur in medial prefrontal cortex circuits during remote memory formation. Whether extinction reverts or further reshapes these circuits is, however, unknown. Here we show that the number and the size of spines were enhanced in anterior cingulate (aCC) and infralimbic...... (ILC) cortices 36 d following contextual fear conditioning. Upon extinction, aCC spine density returned to baseline, but the enhanced proportion of large spines did not. Differently, ILC spine density remained elevated, but the size of spines decreased dramatically. Thus, extinction partially erases...

  9. Mind-Reading Ability and Structural Connectivity Changes in Aging

    OpenAIRE

    Cabinio, Monia; Rossetto, Federica; Blasi, Valeria; Savazzi, Federica; Castelli, Ilaria; Massaro, Davide; Valle, Annalisa; Nemni, Raffaello; Clerici, Mario; Marchetti, Antonella; Baglio, Francesca

    2015-01-01

    The Mind-Reading ability through the eyes is an important component of the affective Theory of Mind (ToM), which allows people to infer the other’s mental state from the eye gaze. The aim of the present study was to investigate to which extent age-associated structural brain changes impact this ability and to determine if this association is related to executive functions in elderly subjects. For this purpose, Magnetic Resonance Imaging was used to determine both gray matter and white matter ...

  10. Mind-Reading ability and structural connectivity changes in aging

    OpenAIRE

    Monia eCabinio; Federica eRossetto; Federica eRossetto; Valeria eBlasi; Federica eSavazzi; Ilaria eCastelli; Davide eMassaro; Annalisa eValle; Raffaello eNemni; Raffaello eNemni; Mario eClerici; Mario eClerici; Antonella eMarchetti; Francesca eBaglio

    2015-01-01

    The Mind-Reading ability through the eyes is an important component of the affective Theory of Mind (ToM), which allows people to infer the other’s mental state from the eye gaze. The aim of the present study was to investigate to which extent age-associated structural brain changes impact this ability and to determine if this association is related to executive functions in elderly subjects. For this purpose, Magnetic Resonance Imaging was used to determine both gray matter and white matter ...

  11. Late Posthemorrhagic Structural and Functional Changes in Pulmonary Circulation Arteries

    Directory of Open Access Journals (Sweden)

    S. A. Andreyeva

    2008-01-01

    Full Text Available Objective: to reveal the major regularities and mechanisms of morphological changes in the rat pulmonary circulation arteries in the late posthemorrhagic period and to compare them with age-related features of the vessels. Materials and methods: experiments to generate graduated hemorrhagic hypotension with the blood pressure being maintained at 40 mm Hg were carried out on young (5—6-month albino male Wistar rats. Throughout hypotension and 60 days after blood loss, the blood was tested to determine low and average molecular-weight substances by spectrophotometry and the pro- and antioxidative systems by chemiluminescence. Pulmonary circulation arteries were morphologically studied in young animals, rats in the late posthemorrhagic period and old (24—25-month rats. Results. Sixty-minute hemorrhagic hypotension leads to the development of endotoxemia and imbalance of the pro- and antioxidative systems, the signs of which are observed in the late periods (2 months after hypotension. At the same time, the posthemorrhagic period is marked by the significant pulmonary circulation arterial morphological changes comparable with their age-related alterations in old rat. This shows up mainly in the reorganization of a connective tissue component in the vascular wall: the elevated levels of individual collagen fibers, their structural changes, elastic medial membrane destruction and deformity. At the same time, there is a change in the morphometric parameters of vessels at all study stages while their lowered flow capacity is only characteristic for intraorgan arteries. Conclusion: The increased activity of free radical oxidation and endotoxemia may be believed to be one of the causes of morphological changes in pulmonary circulation arteries in the late posthemorrhagic period, which is similar to age-related vascular alterations. Key words: hemorrhagic hypotension, pulmonary circulation arteries, free radical oxidation, endotoxemia, remodeling, late

  12. Structural changes in the regenerating rat thymus after irradiation

    International Nuclear Information System (INIS)

    Fukumoto, Tetsuo; Wang, Yu-Hsueh; Hashimoto, Noriko; Tokuda, Nobuko; Sawada, Tomoo

    1999-01-01

    The structural changes of the rat thymus after irradiation were examined. Thymocytes regenerate rapidly after irradiation and the mechanism responsible for this rapid regeneration was examined analyzing vascular and immunohistochemical changes in the thymus. Following results were obtained: Vascular fine mesh works in the cortex were destroyed on day 3 after 6 Gy irradiation, while on day 5 these changes appeared to be restored to almost normal. Massive macrophage accumulations were observed in the cortex on day 3-5 after irradiation. This may be due to clean up the damaged thymocytes, although other possibility, as production of cytokines which may contribute to the rapid proliferation must be intensively examined. Immunohistochemical staining with anti MHC class II molecule showed relatively strong staining in the medulla compared to the cortex in the normal thymus, while this finding was reversed and cortex stained heavily compared to the medulla on day 5-7 after irradiation suggesting the importance of the cortical MHC class II positive thymic epithelial cells in regeneration of thymocytes. Anti FTS antibody stained relatively strongly in the irradiated and recovering thymus compared to the normal. These results may partly explain the abrupt proliferation of thymocytes after irradiation and further studies on cytokine message changes and thymic epithelial characterization responsible to produce the cytokines for the effective thymocyte proliferation are on the way of analysis. (author)

  13. Structural changes in the regenerating rat thymus after irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fukumoto, Tetsuo; Wang, Yu-Hsueh; Hashimoto, Noriko; Tokuda, Nobuko; Sawada, Tomoo [Yamaguchi Univ., Ube (Japan). School of Medicine

    1999-11-01

    The structural changes of the rat thymus after irradiation were examined. Thymocytes regenerate rapidly after irradiation and the mechanism responsible for this rapid regeneration was examined analyzing vascular and immunohistochemical changes in the thymus. Following results were obtained: Vascular fine mesh works in the cortex were destroyed on day 3 after 6 Gy irradiation, while on day 5 these changes appeared to be restored to almost normal. Massive macrophage accumulations were observed in the cortex on day 3-5 after irradiation. This may be due to clean up the damaged thymocytes, although other possibility, as production of cytokines which may contribute to the rapid proliferation must be intensively examined. Immunohistochemical staining with anti MHC class II molecule showed relatively strong staining in the medulla compared to the cortex in the normal thymus, while this finding was reversed and cortex stained heavily compared to the medulla on day 5-7 after irradiation suggesting the importance of the cortical MHC class II positive thymic epithelial cells in regeneration of thymocytes. Anti FTS antibody stained relatively strongly in the irradiated and recovering thymus compared to the normal. These results may partly explain the abrupt proliferation of thymocytes after irradiation and further studies on cytokine message changes and thymic epithelial characterization responsible to produce the cytokines for the effective thymocyte proliteration are on the way of analysis. (author)

  14. Monitoring Seismic Velocity Change to Explore the Earthquake Seismogenic Structures

    Science.gov (United States)

    Liao, C. F.; Wen, S.; Chen, C.

    2017-12-01

    Studying spatial-temporal variations of subsurface velocity structures is still a challenge work, but it can provide important information not only on geometry of a fault, but also the rheology change induced from the strong earthquake. In 1999, a disastrous Chi-Chi earthquake (Mw7.6; Chi-Chi EQ) occurred in central Taiwan and caused great impacts on Taiwan's society. Therefore, the major objective of this research is to investigate whether the rheology change of fault can be associated with seismogenic process before strong earthquake. In addition, after the strike of the Chi-Chi EQ, whether the subsurface velocity structure resumes to its steady state is another issue in this study. Therefore, for the above purpose, we have applied a 3D tomographic technique to obtain P- and S-wave velocity structures in central Taiwan using travel time data provided by the Central Weather Bureau (CWB). One major advantage of this method is that we can include out-of-network data to improve the resolution of velocity structures at deeper depths in our study area. The results show that the temporal variations of Vp are less significant than Vs (or Vp/Vs ratio), and Vp is not prominent perturbed before and after the occurrence of the Chi-Chi EQ. However, the Vs (or Vp/Vs ratio) structure in the source area demonstrates significant spatial-temporal difference before and after the mainshock. From the results, before the mainshock, Vs began to decrease (Vp/Vs ratio was increased as well) at the hanging wall of Chelungpu fault, which may be induced by the increasing density of microcracks and fluid. But in the vicinities of Chi-Chi Earthquake's source area, Vs was increasing (Vp/Vs ratio was also decreased). This phenomenon may be owing to the closing of cracks or migration of fluid. Due to the different physical characteristics around the source area, strong earthquake may be easily nucleated at the junctional zone. Our findings suggest that continuously monitoring the Vp and Vs (or

  15. Brain structural complexity and life course cognitive change.

    Science.gov (United States)

    Mustafa, Nazahah; Ahearn, Trevor S; Waiter, Gordon D; Murray, Alison D; Whalley, Lawrence J; Staff, Roger T

    2012-07-02

    Fractal measures such as fractal dimension (FD) can quantify the structural complexity of the brain. These have been used in clinical neuroscience to investigate brain development, ageing and in studies of psychiatric and neurological disorders. Here, we examined associations between the FD of white matter and cognitive changes across the life course in the absence of detectable brain disease. The FD was calculated from segmented cerebral white matter MR images in 217 subjects aged about 68years, in whom archived intelligence scores from age 11years were available. Cognitive test scores of fluid and crystallised intelligence were obtained at the time of MR imaging. Significant differences were found (intracranial volume, brain volume, white matter volume and Raven's Progressive Matrices score) between men and women at age 68years and novel associations were found between FD and measures of cognitive change over the life course from age 11 to 68years. Those with greater FD were found to have greater than expected fluid abilities at age 68years than predicted by their childhood intelligence and less cognitive decline from age 11 to 68years. These results are consistent with other reports that FD measures of cortical structural complexity increase across the early life course during maturation of the cerebral cortex and add new data to support an association between FD and cognitive ageing. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Export diversification and structural changes in South Africa

    Directory of Open Access Journals (Sweden)

    Ireen Choga

    2015-07-01

    Full Text Available What is the nature and extent of export diversification in South Africa? The primary purpose of this paper is to seek empirical answers to this question. In an attempt to derive empirical measures of the extent of export diversification and the structural changes taking place in South Africa, this paper uses a sample of a group of 28 selected commodities for the period 1980-2012 for which the most recent data is available. The following methods were used to measure the extent of export diversification and the structural changes in export diversification: Commodity-specific cumulative export Experience function, the Commodity-specific traditional index (CSTI, variance of CSTI, concentration ratio and the aggregate specialisation index. The Commodity-Specific Cumulative Experience Function plots show that roughly, commodities such as scientific equipment, transport equipment, motor vehicles, furniture, machinery and electronic products were shifted to the right indicating that the commodities are non-traditional in nature whereas gold coal agricultural products and wood are traditional in nature. The CSTI rankings indicated that motor vehicle exports ranked first showing that motor vehicles are non-traditional exports. Findings of this paper corroborate findings of other scholars; we conclude that our results are complementary.

  17. LONGITUDINAL STRUCTURAL CHANGES IN LATE-ONSET RETINAL DEGENERATION.

    Science.gov (United States)

    Cukras, Catherine; Flamendorf, Jason; Wong, Wai T; Ayyagari, Radha; Cunningham, Denise; Sieving, Paul A

    2016-12-01

    To characterize longitudinal structural changes in early stages of late-onset retinal degeneration to investigate pathogenic mechanisms. Two affected siblings, both with a S163R missense mutation in the causative gene C1QTNF5, were followed for 8+ years. Color fundus photos, fundus autofluorescence images, near-infrared reflectance fundus images, and spectral domain optical coherence tomography scans were acquired during follow-up. Both patients, aged 45 and 50 years, had good visual acuities (>20/20) in the context of prolonged dark adaptation. Baseline color fundus photography demonstrated yellow-white, punctate lesions in the temporal macula that correlated with a reticular pattern on fundus autofluorescence and near-infrared reflectance imaging. Baseline spectral domain optical coherence tomography imaging revealed subretinal deposits that resemble reticular pseudodrusen described in age-related macular degeneration. During follow-up, these affected areas developed confluent thickening of the retinal pigment epithelial layer and disruption of the ellipsoid zone of photoreceptors before progressing to overt retinal pigment epithelium and outer retinal atrophy. Structural changes in early stages of late-onset retinal degeneration, revealed by multimodal imaging, resemble those of reticular pseudodrusen observed in age-related macular degeneration and other retinal diseases. Longitudinal follow-up of these lesions helps elucidate their progression to frank atrophy and may lend insight into the pathogenic mechanisms underlying diverse retinal degenerations.

  18. Structural analysis of lunar subsurface with Chang'E-3 lunar penetrating radar

    Science.gov (United States)

    Lai, Jialong; Xu, Yi; Zhang, Xiaoping; Tang, Zesheng

    2016-01-01

    Geological structure of the subsurface of the Moon provides valuable information on lunar evolution. Recently, Chang'E-3 has utilized lunar penetrating radar (LPR), which is equipped on the lunar rover named as Yutu, to detect the lunar geological structure in Northern Imbrium (44.1260N, 19.5014W) for the first time. As an in situ detector, Chang'E-3 LPR has relative higher horizontal and vertical resolution and less clutter impact compared to spaceborne radars and earth-based radars. In this work, we analyze the LPR data at 500 MHz transmission frequency to obtain the shallow subsurface structure of the landing area of Chang'E-3 in Mare Imbrium. Filter method and amplitude recovery algorithms are utilized to alleviate the adverse effects of environment and system noises and compensate the amplitude losses during signal propagation. Based on the processed radar image, we observe numerous diffraction hyperbolae, which may be caused by discrete reflectors beneath the lunar surface. Hyperbolae fitting method is utilized to reverse the average dielectric constant to certain depth (ε bar). Overall, the estimated ε bar increases with the depth and ε bar could be classified into three categories. Average ε bar of each category is 2.47, 3.40 and 6.16, respectively. Because of the large gap between the values of ε bar of neighboring categories, we speculate a three-layered structure of the shallow surface of LPR exploration region. One possible geological picture of the speculated three-layered structure is presented as follows. The top layer is weathered layer of ejecta blanket with its average thickness and bound on error is 0.95±0.02 m. The second layer is the ejecta blanket of the nearby impact crater, and the corresponding average thickness is about 2.30±0.07 m, which is in good agreement with the two primary models of ejecta blanket thickness as a function of distance from the crater center. The third layer is regarded as a mixture of stones and soil. The

  19. Structural Analysis of Lunar Subsurface with Chang'E 3 Lunar Penetrating Radar

    Science.gov (United States)

    Xu, Yi; Lai, Jialong; Tang, Zesheng

    2015-04-01

    Geological structure of the subsurface of the Moon provides valuable information for our understanding of lunar evolution. Recently, Chang'E 3 has utilized lunar penetrating radar (LPR), which is equipped on the lunar rover named as Yutu, to detect the lunar geological structure in Northern Imbrium (44.1260N, 19.5014W) for the first time. As an in-situ detector, Chang'E 3 LPR has higher horizontal and vertical resolution and less clutter impact compared to spaceborne radars such as Chandrayaan-1 and Kaguya. In this work, we analyze the LPR data at 500 MHz transmission frequency to obtain the shallow subsurface structure of the landing area of Chang'E 3 in Mare Imbrium. First, filter method and amplitude recover algorithms are introduced for data processing to alleviate the adverse effects of environment and system noises and compensate the amplitude losses during signal propagation. Next, based on the processed LPR data, we present the methods to determine the interfaces between layers. A three-layered structure of the shallow surface of the Moon has been observed. The corresponding real part of relative dielectric constant is inverted with deconvolution method. The average dielectric constants of the surface, second and third layer is 2.8, 3.2 and 3.6, respectively. The phenomenon that the average dielectric constant increases with the depth is consistent with prior art. With the obtained dielectric constants, the thickness of each layer can be calculated. One possible geological picture of the observed three-layered structure is presented as follows. The top layer is lunar regolith with its thickness ranging from 0.59 m to 0.9 m. The second layer is the ejecta blanket of the nearby impact crater, and the corresponding thickness is between 3.6m to 3.9m, which is in good agreement with the model of ejecta blanket thickness (height) as a function of distance from the crater center proposed by Melosh in 1989. The third layer is regarded as early lunar regolith with 4

  20. Changing structure to improve function: one academic health center's experience.

    Science.gov (United States)

    Alexander, B; Davis, L; Kohler, P O

    1997-04-01

    Academic health centers (AHCs) have been under siege for the past few years, with decreased federal and state funding for educational and research programs and increasing competition in the health care marketplace. In addition, many AHCs are burdened with the bureaucratic red tape of large educational institutions, which makes agility in responding to a demanding health care market difficult. The authors describe the response to these threats by Oregon Health Sciences University (OHSU), an approach that has been different from those of most similar institutions. OHSU chose to change its structure from being part of the state system of higher education to being an independent public corporation. The authors outline the political process of building widespread support for the legislation passed in 1995, the key features of the restructuring, the challenges faced before and after the transition to a public corporation, and lessons learned in this metamorphosis to a new form.

  1. A zero density change phase change memory material: GeTe-O structural characteristics upon crystallisation.

    Science.gov (United States)

    Zhou, Xilin; Dong, Weiling; Zhang, Hao; Simpson, Robert E

    2015-06-11

    Oxygen-doped germanium telluride phase change materials are proposed for high temperature applications. Up to 8 at.% oxygen is readily incorporated into GeTe, causing an increased crystallisation temperature and activation energy. The rhombohedral structure of the GeTe crystal is preserved in the oxygen doped films. For higher oxygen concentrations the material is found to phase separate into GeO2 and TeO2, which inhibits the technologically useful abrupt change in properties. Increasing the oxygen content in GeTe-O reduces the difference in film thickness and mass density between the amorphous and crystalline states. For oxygen concentrations between 5 and 6 at.%, the amorphous material and the crystalline material have the same density. Above 6 at.% O doping, crystallisation exhibits an anomalous density change, where the volume of the crystalline state is larger than that of the amorphous. The high thermal stability and zero-density change characteristic of Oxygen-incorporated GeTe, is recommended for efficient and low stress phase change memory devices that may operate at elevated temperatures.

  2. The offshore trend: Structural changes in the wind power sector

    International Nuclear Information System (INIS)

    Markard, Jochen; Petersen, Regula

    2009-01-01

    In recent years, the wind power sector has begun to move offshore, i.e. to use space and good wind speeds on the open sea for large scale electricity generation. Offshore wind power, however, is not just technologically challenging but also a capital intensive and risky business that requires particular financial and organizational resources not all potential investors might have. We therefore address the question, what impact offshore wind power may have on ownership and organizational structures in the wind power sector. We compare on- and offshore wind park ownership in Denmark, the UK and Germany. The analysis shows that offshore wind power in all three countries is dominated by large firms, many of which are from the electricity sector. In Denmark and the UK, also investors from the gas and oil industry play an important role in the offshore wind business. This development represents a major shift for countries such as Germany and Denmark, in which the wind power sector has grown and matured on the basis of investments by individuals, farmers, cooperatives and independent project developers. The structural changes by which offshore wind power is accompanied have consequences for turbine manufacturers, project developers, investors, associations and policy makers in the field.

  3. Changes in the macromolecular structure of coals with pyrolysis temperature

    Energy Technology Data Exchange (ETDEWEB)

    Ndaji, F.E.; Butterfield, I.M.; Thomas, K.M. [University of Newcastle upon Tyne, Newcastle upon Tyne (United Kingdom). Northern Carbon Research Labs., Dept. of Chemistry

    1997-01-01

    The macromolecular structure of coal is characterised by its cross-link density. This paper describes a study of the effect of pyrolysis temperature on the macromolecular structure of coal using solvent swelling techniques. Heat treatment initially dissociates the intermolecular interactions in the coal and cleaves some cross-links, leading to increase in the solvent swelling of the coal, which indicates a decrease in the cross-link density. The solvent swelling reaches a maximum before cross-linking reactions predominate, causing a progressive increase in cross-link density and a decrease in solvent swelling. For lower-rank coals there appears to be an overlap (near the temperature of minimum cross-link density) of the dissociation of intermolecular interactions and thermal decomposition. Appreciable decrease in the apparent cross-link density of high-rank coals as indicated by increase in solvent swelling was observed only after thermal decomposition had commenced. Major decomposition involves cross-linking reactions leading to the formation of chars. However, the solvent swelling characteristics continue to change above the resolidification temperature, eventually ceasing at {approximately}600{degree}C. The results are discussed in relation to measurements of thermoplastic properties and devolatilization characteristics. 23 refs., 4 figs., 3 tabs.

  4. Subsurface structures in the northern Mare Imbrium measured by Chang'E-3 and SELENE

    Science.gov (United States)

    Kumamoto, A.; Ishiyama, K.; Feng, J.

    2016-12-01

    Subsurface structures in the northern Mare Imbrium measured by Chang'E-3 and SELENE have been compared. In Chang'E-3 mission, subsurface radar sounding at (19.51W, 44.12N) was performed by Lunar Penetrating Radar (LPR) onboard the Yutu rover. The LPR was pulse radar operated at two frequencies: 60 MHz and 500 MHz. During its operation period from December 2013 to January 2014, the LPR observed subsurface echoes along the rover's track with total distance of 114 m. From the observation in 60 MHz, the subsurface echoes from buried regolith layers at depths of 35, 50, 140, 240, and 360 m were reported (Xiao et al., 2015). In SELENE mission, global subsurface radar sounding of the moon was performed by Lunar Radar Sounder (LRS) onboard the SELENE (Kaguya) spacecraft from the polar orbit with an altitude of 100 km. The LRS was chirp radar operated in a frequency range from 4-6 MHz. So the range resolution of LRS was 75 m in vacuum. During operation period from December 2007 to September 2008, subsurface echoes from all areas of the Moon was observed with a lateral resolution of 76 m. From the global observation, the subsurface echoes from the buried regolith layers in the neraside maria including Mare Imbrium at depths of several hundred meters were reported (Ono et al., 2009).In the present study, we focus on SELENE/LRS data obtained at (19.50W, 44.12N) which is the nearest to the Chang'E-3 landing site. While clear and large-scale subsurface reflectors, as found in Ono et al. (2009), are not found in it, we can identify some echo components from the depths of 140 ( 2000 ns), 240 ( 4000 ns), and 360 m ( 6000 ns). Further analyses utilizing high-resolution data from Chang'E-3/LPR and large-scale data from SELENE/LRS, we will be able to determine the thickness and large-scale structures of the buried regolith layers found by the both radars, and discuss their formation processes in volcanic history of Mare Imbrium.

  5. Changes in Soil Fungal Community Structure with Increasing Disturbance Frequency.

    Science.gov (United States)

    Cho, Hyunjun; Kim, Mincheol; Tripathi, Binu; Adams, Jonathan

    2017-07-01

    Although disturbance is thought to be important in many ecological processes, responses of fungal communities to soil disturbance have been little studied experimentally. We subjected a soil microcosm to physical disturbance, at a range of frequencies designed to simulate ecological disturbance events. We analyzed the fungal community structure using Illumina HiSeq sequencing of the ITS1 region. Fungal diversity was found to decline with the increasing disturbance frequencies, with no sign of the "humpback" pattern found in many studies of larger sedentary organisms. There is thus no evidence of an effect of release from competition resulting from moderate disturbance-which suggests that competition and niche overlap may not be important in limiting soil fungal diversity. Changing disturbance frequency also led to consistent differences in community composition. There were clear differences in OTU-level composition, with different disturbance treatments each having distinct fungal communities. The functional profile of fungal groups (guilds) was changed by the level of disturbance frequency. These predictable differences in community composition suggest that soil fungi can possess different niches in relation to disturbance frequency, or time since last disturbance. Fungi appear to be most abundant relative to bacteria at intermediate disturbance frequencies, on the time scale we studied here.

  6. Probing magnetoelastic coupling and structural changes in magnetoelectric gallium ferrite.

    Science.gov (United States)

    Mukherjee, Somdutta; Garg, Ashish; Gupta, Rajeev

    2011-11-09

    Temperature dependent x-ray diffraction and Raman spectroscopic studies were carried out on flux-grown single crystals of gallium ferrite with a Ga:Fe ratio of 0.9:1.1. Site occupancy calculations from the Rietveld refinement of the x-ray data led to an estimated magnetic moment of ~0.60 μ(B)/f.u. which was in good agreement with the experimental data. A combination of these two measurements indicates that there is no structural phase transition in the material between 18 and 700 K. A detailed line shape analysis of the Raman mode at ~374 cm(-1) revealed a discontinuity in the peak position data indicating the presence of spin-phonon coupling in gallium ferrite. A correlation of the peak frequency with the magnetization data led to two distinct regions across a temperature ~180 K with appreciable change in the spin-phonon coupling strength from ~0.9 (T change in the coupling strength at ~180 K strongly suggests an altered spin dynamics across this temperature. © 2011 IOP Publishing Ltd

  7. Probing magnetoelastic coupling and structural changes in magnetoelectric gallium ferrite

    International Nuclear Information System (INIS)

    Mukherjee, Somdutta; Gupta, Rajeev; Garg, Ashish

    2011-01-01

    Temperature dependent x-ray diffraction and Raman spectroscopic studies were carried out on flux-grown single crystals of gallium ferrite with a Ga:Fe ratio of 0.9:1.1. Site occupancy calculations from the Rietveld refinement of the x-ray data led to an estimated magnetic moment of ∼0.60 μ B /f.u. which was in good agreement with the experimental data. A combination of these two measurements indicates that there is no structural phase transition in the material between 18 and 700 K. A detailed line shape analysis of the Raman mode at ∼374 cm -1 revealed a discontinuity in the peak position data indicating the presence of spin-phonon coupling in gallium ferrite. A correlation of the peak frequency with the magnetization data led to two distinct regions across a temperature ∼180 K with appreciable change in the spin-phonon coupling strength from ∼0.9 (T -1 (180 K c ). This abrupt change in the coupling strength at ∼180 K strongly suggests an altered spin dynamics across this temperature. (paper)

  8. Do temporal changes in vegetation structure additional to time since fire predict changes in bird occurrence?

    Science.gov (United States)

    Lindenmayer, David B; Candy, Steven G; MacGregor, Christopher I; Banks, Sam C; Westgate, Martin; Ikin, Karen; Pierson, Jennifer; Tulloch, Ayesha; Barton, Philip

    2016-10-01

    Fire is a major ecological process in ecosystems globally. Its impacts on fauna can be both direct (e.g., mortality) and indirect (e.g., altered habitat), resulting in population recovery being driven by several possible mechanisms. Separating direct from indirect impacts of fire on faunal population recovery can be valuable in guiding management of biodiversity in fire-prone environments. However, resolving the influence of direct and indirect processes remains a key challenge because many processes affecting fauna can change concomitantly with time since fire. We explore the mechanisms influencing bird response to fire by posing the question, can temporal changes in vegetation structure predict changes in bird occurrence on sites, and can these be separated from other temporal changes using the surrogate of time since fire? We conducted a 12-yr study of bird and vegetation responses to fire at 124 sites across six vegetation classes in Booderee National Park, Australia. Approximately half of these sites, established in 2002, were burned by a large (>3000 ha) wildfire in 2003. To disentangle collinear effects of temporal changes in vegetation and direct demographic effects on population recovery that are subsumed by time since fire, we incorporated both longitudinal and cross-sectional vegetation effects in addition to time since fire within logistic structural equation models. We identified temporal changes in vegetation structure and richness of plant and bird species that characterized burned and unburned sites in all vegetation classes. For nine bird species, a significant component of the year trend was driven by temporal trends in one of three vegetation variables (number of understory or midstory plant species, or midstory cover). By contrast, we could not separate temporal effects between time since fire and vegetation attributes for bird species richness, reporting rate, and the occurrence of 11 other bird species. Our findings help identify species for

  9. Structural changes in the passage Euaspidoceratiforms-Aspidoceratiforms (Aspidoceratidae, Ammonitina

    Directory of Open Access Journals (Sweden)

    Checa, A.

    1986-06-01

    Full Text Available The structural change from Euaspidoceratiforms to Aspidoceratiforms involves as a primary change the loss of the ribbing connecting both series of tubercles . This alteration must have occurred simultaneously starting from the genera Euaspidoceras and Neaspidoceras, giving rise respectively to Aspidoceras and Pseudowaagenia. Remaining observed transformations between both morphological schemes may be considered as a direct consequence of this primary change, specially with regard to the independence of both ornamental series and the obtaining of more involute schemes.

    El estudio integrador de las transformaciones morfológicas que explican el cambio entre Euaspidoceratiformes (Euaspidoceratinae y Aspidoceratiformes (Aspidoceratinae y Physodoceratinae, permite concluir que la alteración primaria se basa en la desaparición de la costilla que conecta los tubérculos de las filas superior e inferior . A partir de aquí, las restantes modificaciones observadas entre los dos esquemas morfológicos pueden ser consideradas como una consecuencia directa de este cambio primario, sobre todo en lo que concierne a la independencia de las dos series ornamentales y a la obtención de esquemas más involutos . El modelo propuesto permite explicar igualmente las diferencias suturales observadas entre ambos grupos. Por último, se concluye que este proceso ha debido producirse a partir de los géneros Euaspidoceras y Neaspidoceras (Euaspidoceratinae, que dan lugar respectivamente a Aspidoceras (Aspidoceratinae y Pseudowaagenia (Physodoceratinae.

  10. Changes in the structure of coal tar during its thermolysis

    Energy Technology Data Exchange (ETDEWEB)

    Koloc, M.; Bekarek, V.; Rojak, A.; Roubicek, V.

    1983-01-01

    The changes in the structure of coal tar during thermal decomposition at 150 to 500 degrees have been studied (every 50 degrees). The heating was conducted at a speed of 3C per minute. The samples were analyzed using a nuclear magnetic resonance (YaMR) (H-1) method at 60 megahertz in a Varian A-60 instrument. The spectra were measured in a 30 percent solution in hexadeuterium benzene using tetramethylsilane as the external standard. The carbon, hydrogen and nitrogen contents were determined in the microsamples in a Perkin Elmer instrument. The structural parameters (the ratio of the number of aromatic carbon atoms to the total number of carbon atoms, the ratio of the number of aromatic hydrogen atoms to the number of aromatic carbon atoms and the degree of substitution of the aromatic carbon systems by aliphatic substituents) were determined using a Brown Ladner method. The elementary composition with the distribution of hydrogen into aromatic and aliphatic and the carbon into aliphatic and aromatic (including a common one for several nuclei which bears the hydrogen and the aliphatic substituents) was determined using a nuclear magnetic resonance method. All of the studied samples had a high degree of aromatization with small differences. The ratio of the number of aromatic hydrogen atoms to the number of aromatic carbon atoms with an increase in the final temperature from 150 to 500 degrees is reduced from 0.603 to 0.483, which points to the shift of the starting 4 to 5 nuclear systems into 10 to 12 nuclear condensed systems.

  11. PTFE-nanocomposites structure and wear-resistance changing in various methods of structural modification

    Science.gov (United States)

    Mashkov, Yu K.; Ruban, A. S.; Rogachev, E. A.; Chemisenko, O. V.

    2018-01-01

    Conditions of polymer materials usage containing nanoelements as modifiers significantly affect the requirements for their physic-mechanical and tribological properties. However, the mechanisms of nanoparticles effect to the polymers tribotechnical properties have not been studied enough. The article aim is to analyze the results of studying polytetrafluoroethylene modified with cryptocrystalline graphite and silicon dioxide and to determine the effectiveness of the modification methods used and methods for further improving filled PTFE mechanical and tribotechnical properties. The effect of modifiers to PCM supramolecular structure was analyzed with SEM methods. The results of modifying the PCM samples surface by depositing a copper film with ion-vacuum deposition methods and changing the structural-phase composition and tribological characteristics are considered. The findings make possible to characterize the physicochemical processes under frictional interaction in metal polymer tribosystems.

  12. Photoreactions and Structural Changes of Anabaena Sensory Rhodopsin

    Directory of Open Access Journals (Sweden)

    Akira Kawanabe

    2009-12-01

    Full Text Available Anabaena sensory rhodopsin (ASR is an archaeal-type rhodopsin found in eubacteria. The gene encoding ASR forms a single operon with ASRT (ASR transducer which is a 14 kDa soluble protein, suggesting that ASR functions as a photochromic sensor by activating the soluble transducer. This article reviews the detailed photoreaction processes of ASR, which were studied by low-temperature Fourier-transform infrared (FTIR and UV-visible spectroscopy. The former research reveals that the retinal isomerization is similar to bacteriorhodopsin (BR, but the hydrogen-bonding network around the Schiff base and cytoplasmic region is different. The latter study shows the stable photoproduct of the all-trans form is 100% 13-cis, and that of the 13-cis form is 100% all-trans. These results suggest that the structural changes of ASR in the cytoplasmic domain play important roles in the activation of the transducer protein, and photochromic reaction is optimized for its sensor function.

  13. THORACOLUMBAR BURST FRACTURE: STRUCTURAL CHANGES AND CLINICAL OUTCOME OF TREATMENT

    Directory of Open Access Journals (Sweden)

    Rodrigo Arnold Tisot

    2016-03-01

    Full Text Available ABSTRACT Objective: To evaluate the correlation between structural changes in burst fractures of thoracic and lumbar spine with clinical outcome of the treatment. Methods: A retrospective study in 25 patients with fractures of thoracic and lumbar spine burst fractures without neurological deficit. Eleven patients underwent conservative treatment and for the remaining the treatment was surgical. All patients were followed up for at least 24 months. The cases were evaluated by a protocol that included: posttraumatic measurement of kyphosis, vertebral body collapse and narrowing of the spinal canal, the visual analog scale of pain, and the quality of life questionnaire SF-36 at the follow-up. For statistical analysis, the significance level was 5% and the software SPSS 18.0 was used. Results: No statistically significant difference was observed when comparing the clinical outcomes of one treatment over another. Similarly, there was no statistically significant correlation between kyphosis and post-traumatic narrowing of the spinal canal with clinical worsening in the follow-up, regardless of the treatment used. We found a positive correlation (p<0.05 between initial collapse and SF-36 domains in both groups (operated and non-operated. Conclusion: There was no significant superiority of one treatment over the other, and no correlation was found between kyphosis and spinal canal narrowing in burst fractures of the thoracic and lumbar spine without neurological deficit. However, there was correlation between initial collapse and clinical outcome in some domains of the SF-36 questionnaire.

  14. Structural and functional brain changes in posttraumatic stress disorder.

    Science.gov (United States)

    Nutt, David J; Malizia, Andrea L

    2004-01-01

    Posttraumatic stress disorder (PTSD) is a highly disabling condition that is associated with intrusive recollections of a traumatic event, hyperarousal, avoidance of clues associated with the trauma, and psychological numbing. The field of neuroimaging has made tremendous advances in the past decade and has contributed greatly to our understanding of the physiology of fear and the pathophysiology of PTSD. Neuroimaging studies have demonstrated significant neurobiologic changes in PTSD. There appear to be 3 areas of the brain that are different in patients with PTSD compared with those in control subjects: the hippocampus, the amygdala, and the medial frontal cortex. The amygdala appears to be hyperreactive to trauma-related stimuli. The hallmark symptoms of PTSD, including exaggerated startle response and flashbacks, may be related to a failure of higher brain regions (i.e., the hippocampus and the medial frontal cortex) to dampen the exaggerated symptoms of arousal and distress that are mediated through the amygdala in response to reminders of the traumatic event. The findings of structural and functional neuroimaging studies of PTSD are reviewed as they relate to our current understanding of the pathophysiology of this disorder.

  15. Structural and Functional Changes in Human Kidneys with Healthy Aging.

    Science.gov (United States)

    Hommos, Musab S; Glassock, Richard J; Rule, Andrew D

    2017-10-01

    Aging is associated with significant changes in structure and function of the kidney, even in the absence of age-related comorbidities. On the macrostructural level, kidney cortical volume decreases, surface roughness increases, and the number and size of simple renal cysts increase with age. On the microstructural level, the histologic signs of nephrosclerosis (arteriosclerosis/arteriolosclerosis, global glomerulosclerosis, interstitial fibrosis, and tubular atrophy) all increase with age. The decline of nephron number is accompanied by a comparable reduction in measured whole-kidney GFR. However, single-nephron GFR remains relatively constant with healthy aging as does glomerular volume. Only when glomerulosclerosis and arteriosclerosis exceed that expected for age is there an increase in single-nephron GFR. In the absence of albuminuria, age-related reduction in GFR with the corresponding increase in CKD (defined by an eGFRage-standardized mortality risk or ESRD. These findings raise the question of whether disease labeling of an age-related decline in GFR is appropriate. These findings also emphasize the need for a different management approach for many elderly individuals considered to have CKD by current criteria. Copyright © 2017 by the American Society of Nephrology.

  16. Structural changes in brain substance in children with epilepsy (MRI findings)

    International Nuclear Information System (INIS)

    Kaduk, Je.G.

    2000-01-01

    The structural changes in the brain substance and the parameters of liquor-containing spaces in children with epilepsy are studied. Structural morphological changes in the brain were found in 30, 7 % of cases. In 27, 7 % MRI findings did not differ from the control. The number of porencephalic changes in the both groups was similar (4, 2 - 4, 3 % of cases). Hypotrophy of cortical and subcortical structures, dysgenesis of the colossal body were observed in the group of local epilepsy. Typodense changes of pervantricular structures were more frequent in the patients will local disease. Hypodense changes of the periventricular structures were more frequent in the patients with local disturbances

  17. The changing market for wood materials used in farm structures.

    Science.gov (United States)

    David C. Baumgartner

    1971-01-01

    This reports describes the number, type, and size of farm structures built in a 17-state area during the years 1963-1965, together with information relating to the use and marketing of wood materials in such structures.

  18. Team models in neurorehabilitation: structure, function, and culture change.

    Science.gov (United States)

    Karol, Robert L

    2014-01-01

    Neurorehabilitation requires a team effort. Over time the nature of teams has evolved from single discipline work through multi-disciplinary and inter-disciplinary teams to trans-disciplinary teams. However, there are inconsistencies in the literature and clinical practice as to the structure and function of these team models. Each model engenders advantages over its predecessor and unless the models are well understood clinicians may labor in a model that is less efficacious than the most transcendent model. To define and examine the models of single discipline care, multi-disciplinary teams, inter-disciplinary teams, and trans-disciplinary teams and to review in depth trans-disciplinary teams as the most advanced team model. This paper will also consider professional roles and integration across disciplines as well as the crucial topics of staff selection, attendance in rounds and the nature of rounds, staff physical plant assignments, and leadership responsibilities. Leadership responsibilities that will be addressed include scope of practice and role release, peer pressure, and culture change issues. The trans-disciplinary model is the gold standard for teams in neurorehabilitation because they entail more integrated service delivery than do other teams. Trans-disciplinary teams also represent a more persons-centered approach. To initiate a trans-disciplinary model, team members must have excellent communication and shared decision making including persons with brain injury. Leadership must address staff selection, scope of practice and role-release. Otherwise, the model will fail due to peer pressure and institutional or program cultural variables.

  19. Enamel structural changes induced by hydrochloric and phosphoric acid treatment.

    Science.gov (United States)

    Bertacci, Angelica; Lucchese, Alessandra; Taddei, Paola; Gherlone, Enrico F; Chersoni, Stefano

    2014-12-30

    The aim of this study was to evaluate enamel acid-induced structural changes after 2 different treatments, by means of Raman and infrared (IR) spectroscopy analyses, and to correlate these findings with permeability measured as fluid discharge from outer enamel. Two different treatments were investigated: 10 enamel slices were etched with 15% hydrochloric acid (HCl) for 120 seconds and 10 slices with 37% phosphoric acid gel (H3PO4) for 30 seconds, rinsed for 30 seconds and then air-dried for 20 seconds. Powders of enamel treated as previously described were produced. Replicas of enamel subjected to the same treatments were obtained to evaluate the presence of fluid droplets on enamel surface. Raman and IR spectroscopy showed that the treatment with both hydrochloric and phosphoric acids induced a decrease in the carbonate content of the enamel apatite. At the same time, both acids induced the formation of HPO42- ions. After H3PO4 treatment, the bands due to the organic component of enamel decreased in intensity, while they increased after HCl treatment. Replicas of H3PO4 treated enamel showed a strongly reduced permeability. Replicas of HCl 15% treated samples showed a maintained permeability. A decrease of the enamel organic component, as resulted after H3PO4 treatment, involves a decrease in enamel permeability, while the increase of the organic matter (achieved by HCl treatment) still maintains enamel permeability.The results suggested a correlation between organic matter and enamel permeability. Permeability was affected by etching technique and could be involved in marginal seal, gap and discoloration at the enamel interface, still causes of restoration failure.

  20. Geometric structure and information change in phase transitions

    Science.gov (United States)

    Kim, Eun-jin; Hollerbach, Rainer

    2017-06-01

    We propose a toy model for a cyclic order-disorder transition and introduce a geometric methodology to understand stochastic processes involved in transitions. Specifically, our model consists of a pair of forward and backward processes (FPs and BPs) for the emergence and disappearance of a structure in a stochastic environment. We calculate time-dependent probability density functions (PDFs) and the information length L , which is the total number of different states that a system undergoes during the transition. Time-dependent PDFs during transient relaxation exhibit strikingly different behavior in FPs and BPs. In particular, FPs driven by instability undergo the broadening of the PDF with a large increase in fluctuations before the transition to the ordered state accompanied by narrowing the PDF width. During this stage, we identify an interesting geodesic solution accompanied by the self-regulation between the growth and nonlinear damping where the time scale τ of information change is constant in time, independent of the strength of the stochastic noise. In comparison, BPs are mainly driven by the macroscopic motion due to the movement of the PDF peak. The total information length L between initial and final states is much larger in BPs than in FPs, increasing linearly with the deviation γ of a control parameter from the critical state in BPs while increasing logarithmically with γ in FPs. L scales as |lnD | and D-1 /2 in FPs and BPs, respectively, where D measures the strength of the stochastic forcing. These differing scalings with γ and D suggest a great utility of L in capturing different underlying processes, specifically, diffusion vs advection in phase transition by geometry. We discuss physical origins of these scalings and comment on implications of our results for bistable systems undergoing repeated order-disorder transitions (e.g., fitness).

  1. Future Agribusiness Challenges: Strategic Uncertainty, Innovation and Structural Change

    NARCIS (Netherlands)

    Boehlje, M.; Roucan-Kane, M.; Bröring, S.

    2011-01-01

    The global food and agribusiness industry is in the midst of major changes, and the pace of change seems to be increasing. These changes suggest three fundamental critical future issues for the sector: 1) decisions must be made in an environment of increasing risk and uncertainty, 2) developing and

  2. Damage assessment in structure from changes in static parameter ...

    Indian Academy of Sciences (India)

    The basic strategy applied in this study is to train a neural network to recognize the behaviour of the undamaged structure as well as of the structure with various possible damaged states. When this trained network is subjected to the measured response, it should be able to detect any existing damage. This idea is applied ...

  3. Structural changes during the unfolding of Bovine serum albumin in ...

    Indian Academy of Sciences (India)

    400Da [9]. Low-angle X-ray scattering [10] and neutron scattering [11] also in- dicated serum albumin to be a prolate ellipsoid. However, studies using 1H NMR indicated that a prolate structure was unlikely; rather a heart-shaped structure was proposed [12]. The shape of albumin reveals a heart-shaped molecule that can.

  4. Damage assessment in structure from changes in static parameter ...

    Indian Academy of Sciences (India)

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

    Here, structural responses are given as input to the neural network, while parameters to be identified are shown to the network as desired data. Finally some structural responses measured are given to the well-trained network, which immediately outputs the appropriate value of parameters for untrained patterns. The model.

  5. Pressure-induced changes in the structural and absorption ...

    Indian Academy of Sciences (India)

    and absorption properties of NADNP under hydrostatic pressure of 0–140 GPa. The atomic positions and the unit cell parameters were allowed to relax to the min- imum energy configuration to investigate the crystal structure at different pressures. Then, we examined the variations in electronic structure under compres-.

  6. Mixing biases: Structural changes in the as topology evolution

    NARCIS (Netherlands)

    Haddadi, H.; Fay, D.; Uhlig, S.; Moore, A.; Mortier, R.; Jamakovic, A.

    2010-01-01

    In this paper we study the structural evolution of the AS topology as inferred from two different datasets over a period of seven years. We use a variety of topological metrics to analyze the structural differences revealed in the AS topologies inferred from the two different datasets. In

  7. 28 CFR 0.191 - Changes which affect the overall structure of the Department.

    Science.gov (United States)

    2010-07-01

    ... structure of the Department. 0.191 Section 0.191 Judicial Administration DEPARTMENT OF JUSTICE ORGANIZATION OF THE DEPARTMENT OF JUSTICE Sections and Subunits § 0.191 Changes which affect the overall structure of the Department. Changes to the overall structure of the Department include: The establishment...

  8. Structural change in European power and gas industries

    International Nuclear Information System (INIS)

    2000-01-01

    After decades of stability the European power and gas industries are now undergoing fundamental changes. Made possible by policy reforms and technological developments, these changes are largely driven by commercial forces which have developed their own momentum and dynamics. New commercial risks are a key feature of the emerging market order and companies cannot protect themselves through a ''no move strategy''. This report explores the key changes and examines the emerging commercial strategies in response to the new environment. (author)

  9. Climate change and its impact on structural safety

    NARCIS (Netherlands)

    Steenbergen, R.D.J.M.; Geurts, C.P.W.; Bentum, C.A. van

    2009-01-01

    Extreme climatic events lead to loads on buildings and civil engineering works. Changes in climate will have an effect on the design loads. This paper presents an investigation into the relevance of the climate change scenarios with respect to the loads on buildings by wind, precipitation and

  10. Urban forest structure, ecosystem services and change in Syracuse, NY

    Science.gov (United States)

    David J. Nowak; Robert E. Hoehn; Allison R. Bodine; Eric J. Greenfield; Jarlath. O' Neil-Dunne

    2013-01-01

    The tree population within the City of Syracuse was assessed using a random sampling of plots in 1999, 2001 and 2009 to determine how the population and the ecosystem services these trees provide have changed over time. Ecosystem services and values for carbon sequestration, air pollution removal and changes in building energy use were derived using the i-Tree Eco...

  11. Cultural and structural changes in radioactive waste management organisations

    International Nuclear Information System (INIS)

    2007-01-01

    In recent years the socio-political environment of radioactive waste management (RWM) has been changing in a significant way. Stakeholder dialogue has become a leading principle. How have RWM organisations adapted to this societal transition? How do they balance the requirement of openness and the increasing concerns over the security of facilities? Are there organisations that have successfully changed from a technical- to a customer-focused culture? What resistance was met? Which tools and instruments helped organisations evolve? This report documents the changes observed by RWM managers and sets those changes in an organisational sciences framework. All those who are intent on learning about the changes that have taken place in the field of radioactive waste management, or whose own organisations in any sector must adapt to societal demand, will be interested by the experience and insight reported here. (authors)

  12. Ownership Structure and Earnings Management in periods of Executive Changes

    DEFF Research Database (Denmark)

    Sommer, Rasmus S.

    This paper reports evidence of earnings management associated with non-routine executive changes in a Danish context. It is hypothesised that incoming executives in non-owner-controlled companies decrease earnings by means of discretionary accruals in the financial statements relating to the period...... of the executive change. A modified, modified Jones model is used to divide income before tax into discretionary and non-discretionary components. The empirical evidence is consistent with the hypothesis. Non-owner-controlled companies significantly decrease earnings around executive changes, while...

  13. The Changing Rules of the Game, Volleyball Player Systematic Structure and Effects in Applying

    OpenAIRE

    DİNÇER, Özgür

    2015-01-01

    Purpose: We the purpose of this study, ranging from past to present and play volleyball rule changes that occur related to industry structure, how structure affects in applying with a systematic trial. Method: Volleyball, starting from the date of the present day sports entertainment, sport has become a subject performance. . As regards; the changing rules of the game, in terms of volleyball player systematic structure and effects on performance. The changing rules of the game, volleyball pla...

  14. The Structure of Lombricine Kinase: Implications for Phosphagen Conformational Changes

    Energy Technology Data Exchange (ETDEWEB)

    Bush, D. Jeffrey; Kirillova, Olga; Clark, Shawn A.; Davulcu, Omar; Fabiola, Felcy; Xie, Qing; Somasundaram, Thayumanasamy; Ellington, W. Ross; Chapman, Michael S. (Oregon HSU); (FSU)

    2012-05-29

    Lombricine kinase is a member of the phosphagen kinase family and a homolog of creatine and arginine kinases, enzymes responsible for buffering cellular ATP levels. Structures of lombricine kinase from the marine worm Urechis caupo were determined by x-ray crystallography. One form was crystallized as a nucleotide complex, and the other was substrate-free. The two structures are similar to each other and more similar to the substrate-free forms of homologs than to the substrate-bound forms of the other phosphagen kinases. Active site specificity loop 309-317, which is disordered in substrate-free structures of homologs and is known from the NMR of arginine kinase to be inherently dynamic, is resolved in both lombricine kinase structures, providing an improved basis for understanding the loop dynamics. Phosphagen kinases undergo a segmented closing on substrate binding, but the lombricine kinase ADP complex is in the open form more typical of substrate-free homologs. Through a comparison with prior complexes of intermediate structure, a correlation was revealed between the overall enzyme conformation and the substrate interactions of His{sup 178}. Comparative modeling provides a rationale for the more relaxed specificity of these kinases, of which the natural substrates are among the largest of the phosphagen substrates.

  15. Structural change of the economy, technological progress and long-term energy demand

    DEFF Research Database (Denmark)

    Klinge Jacobsen, Henrik

    ) the effect on energy demand of structural changes exemplified by changes in the energy supply sector and in Danish trade patterns. The report highlights a few aspects of the interaction between structural economic changes and energy demand, but it does not intend to cover a wide range of issues related...... change of a specific sector, namely the energy supply sector, and the implications for long-term energy demand. The last two papers are devoted to the structural change of trade patterns and its implications for long-term energy demand from industries and the effects on trade from changes in energy...... on different aspects of structural change of the economy and energy demand. Three different issues related to long-term energy demand are discussed: (1) the importance of technological change and its representation in energy-economy modelling, (2) an integration of two different modelling approaches, and (3...

  16. Structural changes in manufacturing industry at division level: Serbia and new EU member states

    Directory of Open Access Journals (Sweden)

    Savić Ljubodrag

    2015-01-01

    Full Text Available Research in this paper is oriented towards structural changes at the division level of the manufacturing industry. The goal of the research is to point at the significance of the efficient structural reforms of Serbia's manufacturing industry, more precisely to point at the size, intensity, speed and directions of the changes made in its structure. In the paper, the basic indicators of structural changes are used, namely the trend of the share of employment and the value added. The size of the changes is analyzed by the standard deviation and the dispersion of growth rates, whereas the intensity of changes is analyzed by the elasticity of the divisions' growth rates. A correlation analysis is used to determine the directions and nature of the connectedness of structural changes between divisions, whereas the direction of changes is shown by the Spearman rank correlation coefficient of their growth rates. The Structural Change Indicator is used for researching the pace and patterns of structural changes. At the division level, by applying the comparison method, differences in the directions, speed and patterns of the structural changes of the Serbian manufacturing industry are analyzed against the new EU member states for which there are comparative data (Bulgaria, Romania, Hungary, the Czech Republic, Poland, Slovenia and Slovakia. The research results indicate that growth rates were higher in those divisions in which reforms were more comprehensive, faster, more intensive and efficiently fully implemented.

  17. Family Structure Changes and Children's Health, Behavior, and Educational Outcomes

    DEFF Research Database (Denmark)

    Rasmussen, Astrid Würtz

    More and more children do not grow up in traditional nuclear families. Instead they grow up in single parent households or in families with a step-parent. Hence it is important to improve our understanding of the impact of 'shocks' in family structure due to parental relationship dissolution...... on children. In this study I empirically test whether children are traumatized by shocks in the family structure during childhood. I focus on both educational, behavioral, and health outcomes. A population sample of Danish children born in January to May 1983, 1984, and 1985 is used for the analysis...

  18. Family Structure Changes and Children's Health, Behavior, and Educational Outcomes

    DEFF Research Database (Denmark)

    Rasmussen, Astrid Würtz

    More and more children do not grow up in traditional nuclear families. Instead they grow up in single parent households or in families with a step-parent. Hence it is important to improve our understanding of the impact of "shocks" in family structure due to parental relationship dissolution...... on children. In this study I empirically test whether children are traumatized both in the short and the long run by shocks in the family structure during childhood. I focus on educational, behavioral, and health outcomes. A population sample of Danish children born in January to May 1983, 1984, and 1985...

  19. Functional and Structural Brain Changes Associated with Methamphetamine Abuse

    Directory of Open Access Journals (Sweden)

    Bruce R. Russell

    2012-10-01

    Full Text Available Methamphetamine (MA is a potent psychostimulant drug whose abuse has become a global epidemic in recent years. Firstly, this review article briefly discusses the epidemiology and clinical pharmacology of methamphetamine dependence. Secondly, the article reviews relevant animal literature modeling methamphetamine dependence and discusses possible mechanisms of methamphetamine-induced neurotoxicity. Thirdly, it provides a critical review of functional and structural neuroimaging studies in human MA abusers; including positron emission tomography (PET and functional and structural magnetic resonance imaging (MRI. The effect of abstinence from methamphetamine, both short- and long-term within the context of these studies is also reviewed.

  20. Characteristics of de novo structural changes in the human genome

    NARCIS (Netherlands)

    Kloosterman, Wigard P.; Francioli, Laurent C.; Hormozdiari, Fereydoun; Marschall, Tobias; Hehir-Kwa, Jayne Y.; Abdellaoui, Abdel; Lameijer, Eric-Wubbo; Moed, Matthijs H.; Koval, Vyacheslav; Renkens, Ivo; van Roosmalen, Markus J.; Arp, Pascal; Karssen, Lennart C.; Coe, Bradley P.; Handsaker, Robert E.; Suchiman, Eka D.; Cuppen, Edwin; Thung, Djie Tjwan; McVey, Mitch; Wendl, Michael C.; Uitterlinden, Andre; van Duijn, Cornelia M.; Swertz, Morris A.; Wijmenga, Cisca; van Ommen, GertJan B.; Slagboom, P. Eline; Boomsma, Dorret I.; Schoenhuth, Alexander; Eichler, Evan E.; de Bakker, Paul I. W.; Ye, Kai; Guryev, Victor

    Small insertions and deletions (indels) and large structural variations (SVs) are major contributors to human genetic diversity and disease. However, mutation rates and characteristics of de novo indels and SVs in the general population have remained largely unexplored. We report 332 validated de

  1. Structural changes and effect of denopamine on alveolar fluid ...

    African Journals Online (AJOL)

    GREGORY

    2010-09-13

    Sep 13, 2010 ... The epithelial cellular structure of control rat. (×12000). stimulatory effects of terbutaline on AFC (Gu et al., 2001). To determine whether hypoxia altered the effects of denopamine on amiloride-sensitive and amiloride- insensitive sodium channels, an isomolar albumin solution in the presence of 10-5 mol/L ...

  2. Frequency effects and structural change – the Afrikaans preterite

    African Journals Online (AJOL)

    According to emergent grammar and exemplar theory in cognitive linguistics, the frequency of an item affects its .... Variability and variation is seen as a fundamental part of language (Bybee and Hopper 2001: 19; Croft 2001: .... innate structure for language acquisition, that language is a highly modular system, and that the.

  3. Structural changes in polytetrafluoroethylene molecular chains upon sliding against steel

    NARCIS (Netherlands)

    Shen, J.T.; Pei, Y.T.; Hosson, J.Th.M. De

    In this work, the influence of dry sliding between a steel counterpart ball and polytetrafluoroethylene (PTFE) plate sample on the transformation of PTFE molecular structure is investigated. With X-ray diffraction, differential scanning calorimetry, Fourier transform infrared (FT-IR) spectroscopy

  4. Damage assessment in structure from changes in static parameter ...

    Indian Academy of Sciences (India)

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

    ment method; mean square error. 1. Introduction. Structural systems in a wide range of aeronautical, mechanical and civil engineering fields are prone to damage and deterioration during their service life. So an effective and reliable damage assessment methodology will be a valuable tool in timely determination of damage.

  5. An efficient structural reanalysis model for general design changes ...

    African Journals Online (AJOL)

    Approximate structural reanalysis methods have long been pursued in quest for efficiency so as to enhance their practical' application in the assessment and verification of designs following design modifications, These have been of significant practical importance with particular emphasis on design optimization of ...

  6. Structural transformation, biased technological change, and employment in Vietnam

    DEFF Research Database (Denmark)

    Abbott, Philip; Tarp, Finn; Wu, Ce

    Employment in Vietnam and elsewhere in Asia has grown more slowly than GDP over the last several decades. This means GDP per capita is rising. Vietnamese policymakers, however, are concerned that ongoing structural transformation is creating too few jobs. We use data for seven aggregated sectors...

  7. Structural Transformation, Biased Technological Change, and Employment in Vietnam

    DEFF Research Database (Denmark)

    Abbott, Philip; Tarp, Finn; Wu, Ce

    2015-01-01

    Employment in Vietnam and elsewhere in Asia has grown more slowly than GDP over the last several decades. This means GDP per capita is rising. Vietnamese policymakers, however, are concerned that ongoing structural transformation is creating too few jobs. We use data for seven aggregated sectors...

  8. Gender equality or patriarchal dividend: Structural change in Turkish nursing.

    Science.gov (United States)

    Herdman, Elizabeth; Badir, Aysel

    2008-06-01

    Turkey is attempting to join the European Union and is facing pressure to eliminate many forms of discrimination, including discrimination based on gender. In keeping with these aims, in early 2007 the Turkish government changed the law to permit Turkish men to become nurses. Given that Turkey is a highly patriarchal society and that occupational segregation by sex is a persistent feature, it is important to examine the potential outcome of the legislative changes. The aim of this paper is to explore the paradoxical potential for Turkish female nurses to experience increased discrimination in a system that is restructured by legislation to be non-discriminatory.

  9. Yellow dextrins: Evaluating changes in structure and colour during processing

    NARCIS (Netherlands)

    Terpstra, K.R.; Woortman, A.J.J.; Hopman, J.C.P.

    2010-01-01

    The preparation of a yellow dextrin is thoroughly characterized during different stages of its production process with a SEC system equipped with four detectors (light scattering, viscosity, UV and RI). With this system, also referred to as SEC-4D, it was shown that the changes in characteristics

  10. VET Provider Market Structures: History, Growth and Change. Research Report

    Science.gov (United States)

    Korbel, Patrick; Misko, Josie

    2016-01-01

    This paper tracks the development of the Australian vocational education and training (VET) provider market over the last two decades in the context of significant policy changes and generally increased competition. It provides an insight into how the sector has arrived at its current position, painting a present-day picture of great diversity.…

  11. Invasive grasses change landscape structure and fire behavior in Hawaii

    Science.gov (United States)

    Lisa M. Ellsworth; Creighton M. Litton; Alexander P. Dale; Tomoaki Miura

    2014-01-01

    How does potential fire behavior differ in grass-invaded non-native forests vs open grasslands? How has land cover changed from 1950–2011 along two grassland/forest ecotones in Hawaii with repeated fires? A study on non-native forest with invasive grass understory and invasive grassland (Megathyrsus maximus) ecosystems on Oahu, Hawaii, USA was...

  12. Protoporphyrin IX-induced structural and functional changes in ...

    Indian Academy of Sciences (India)

    Protoporphyrin IX and its derivatives are used as photosensitizers in the photodynamic therapy of cancer. Protoporphyrin IX penetrates into human red blood cells and releases oxygen from them. This leads to a change in the morphology of the cells. Spectrophotometric studies reveal that protoporphyrin IX interacts with ...

  13. Changes in the trophic structure, abundance and species diversity of ...

    African Journals Online (AJOL)

    Decreases in mean trophic level, the biomass of high trophic level species and indices of species diversity between 1990 and 2009 were observed in commercial catches. These decreases were then related to changes in fishing pressure, fishing strategy and the combined effects of fishing and environmental factors (as ...

  14. Changes in the trophic structure of the southern Benguela before ...

    African Journals Online (AJOL)

    Ecopath with Ecosim was used to construct and compare mass-balanced foodweb models of the southern Benguela ecosystem, representing the following eras of ... trophic control mechanism becoming the dominant driver of ecosystem dynamics, increasing the impact of environmental events including climate change.

  15. Scenarios of long-term farm structural change for application in climate change impact assessment

    NARCIS (Netherlands)

    Mandryk, M.; Reidsma, P.; Ittersum, van M.K.

    2012-01-01

    Towards 2050, climate change is one of the possible drivers that will change the farming landscape, but market, policy and technological development may be at least equally important. In the last decade, many studies assessed impacts of climate change and specific adaptation strategies. However,

  16. Family Structure Changes and Children's Health, Behavior, and Educational Outcomes

    DEFF Research Database (Denmark)

    Rasmussen, Astrid Würtz

    More and more children do not grow up in traditional nuclear families. Instead they grow up in single parent  households or in families with a step-parent. For example, in 1980, almost 83% of all Danish children in the ages 0 to 17 lived with both of their parents, but this number steadily...... decreased to 73% in 2005. Hence it is important to improve our understanding of the impact of "shocks" in family structure due to parental relationship dissolution on children. International studies mainly suggest a negative relationship between non-nuclear family structure and child outcomes. There are two...... childhood. I focus on educational, behavioral and health outcomes and investigate both the selection and causation explanations. For the estimations I use a Danish administrative register dataset with the full population of children born in January to May 1983, 1984, and 1985. I find a clear negative...

  17. The changing structure of the electric power industry: An update

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The U. S. electric power industry today is on the road to restructuring a road heretofore uncharted. While parallels can be drawn from similar journeys taken by the airline industry, the telecommunications industry, and, most recently, the natural gas industry, the electric power industry has its own unique set of critical issues that must be resolved along the way. The transition will be from a structure based on a vertically integrated and regulated monopoly to one equipped to function successfully in a competitive market. The long-standing traditional structure of the electric power industry is the result of a complex web of events that have been unfolding for over 100 years. Some of these events had far-reaching and widely publicized effects. Other major events took the form of legislation. Still other events had effects that are less obvious in comparison (e.g., the appearance of technologies such as transformers and steam and gas turbines, the invention of home appliances, the man-made fission of uranium), and it is likely that their significance in the history of the industry has been obscured by the passage of time. Nevertheless, they, too, hold a place in the underpinnings of today`s electric industry structure. The purpose of this report, which is intended for both lay and technical readers, is twofold. First, it is a basic reference document that provides a comprehensive delineation of the electric power industry and its traditional structure, which has been based upon its monopoly status. Second, it describes the industry`s transition to a competitive environment by providing a descriptive analysis of the factors that have contributed to the interest in a competitive market, proposed legislative and regulatory actions, and the steps being taken by the various components of the industry to meet the challenges of adapting to and prevailing in a competitive environment.

  18. The changing structure of the electric power industry: An update

    International Nuclear Information System (INIS)

    1996-12-01

    The U. S. electric power industry today is on the road to restructuring a road heretofore uncharted. While parallels can be drawn from similar journeys taken by the airline industry, the telecommunications industry, and, most recently, the natural gas industry, the electric power industry has its own unique set of critical issues that must be resolved along the way. The transition will be from a structure based on a vertically integrated and regulated monopoly to one equipped to function successfully in a competitive market. The long-standing traditional structure of the electric power industry is the result of a complex web of events that have been unfolding for over 100 years. Some of these events had far-reaching and widely publicized effects. Other major events took the form of legislation. Still other events had effects that are less obvious in comparison (e.g., the appearance of technologies such as transformers and steam and gas turbines, the invention of home appliances, the man-made fission of uranium), and it is likely that their significance in the history of the industry has been obscured by the passage of time. Nevertheless, they, too, hold a place in the underpinnings of today's electric industry structure. The purpose of this report, which is intended for both lay and technical readers, is twofold. First, it is a basic reference document that provides a comprehensive delineation of the electric power industry and its traditional structure, which has been based upon its monopoly status. Second, it describes the industry's transition to a competitive environment by providing a descriptive analysis of the factors that have contributed to the interest in a competitive market, proposed legislative and regulatory actions, and the steps being taken by the various components of the industry to meet the challenges of adapting to and prevailing in a competitive environment

  19. Credit Rating Change and Capital Structure in Latin America

    Directory of Open Access Journals (Sweden)

    Dany Rogers

    2016-04-01

    Full Text Available This study analyzes the impact of imminent reclassification of credit rating on the decision-making regarding capital structure of non-financial corporations listed in Latin America. Despite the importance attributed by the market agents and the existence of empirical evidence of the effect caused by rating in the capital structure of companies in developed countries, this issue is still incipient in Latin-American countries. For this purpose, all the non-financial corporation owners of, at least one corporate rating issued by an international rating agency were taken into account, with the requirement of being listed on a stock exchange in at least one Latin-American country. Through a data panel analysis comprising the period between 2001 and 2010 and by making use of the Generalized Method of Moments (GMM, the main results that were achieved did not indicate that non-financial corporations listed in Latin America, with imminent reclassification of ratings, adopt less debts than those without an imminent reclassification of their ratings. These findings suggest that the imminent reclassifications of credit ratings do not present important information for managers of non-financial corporations in Latin America when making decisions about capital structure.

  20. CONCEPTUALIZATION OF URBANIZATION STRUCTURE AND CLIMATE CHANGE IN LAGOS, NIGERIA

    OpenAIRE

    Adejobi Oladepo Samson; Olorunnimbe Rafiu O

    2013-01-01

    Urbanization is synonymous with environmental challenges. In developing countries, the challenges have assumed higher dimensions proportionally due to multifarious issues of rapid changes in the environment, due to development, through population growth and industrialization, and accompanied by all kinds of pollution such as air pollution, waste disposal, land use degradation, and vehicular pollution as the resultant effects of man’s interaction with the environment. The main c...

  1. STRUCTURAL LEAF CHANGES IN TREES AROUND A SUBWAY AIR DUCT

    OpenAIRE

    Rodrigues, Renato de Aragão Ribeiro; Vaz, Vanderson Corrêa; Sato, Alice; Arruda, Rosani do Carmo de Oliveira; Castro, Wagner Antonio Chiba de; Silva-Matos, Dalva Maria da

    2015-01-01

    ABSTRACTWhile a number of papers have shown that subway systems have an impact on the air quality through the release of particulate matters, no information about the impact of such particles on tree attributes is available. Tree leaves from three different species from the exit side of a subway station in Rio de Janeiro, Brazil, were more asymmetrical than leaves from the entrance side. This leaves also presenting changes in leaves cuticle and chlorophyll content. RESUMOVários artigos vêm...

  2. Structural leaf changes in trees around a subway air duct.

    OpenAIRE

    RODRIGUES, R. de A. R.; VAZ, V. C.; SATO, A.; ARRUDA, R. do C. de O.; CASTRO, W. A. C. de; SILVA-MATOS, D. M. da.

    2016-01-01

    ABSTRACTWhile a number of papers have shown that subway systems have an impact on the air quality through the release of particulate matters, no information about the impact of such particles on tree attributes is available. Tree leaves from three different species from the exit side of a subway station in Rio de Janeiro, Brazil, were more asymmetrical than leaves from the entrance side. This leaves also presenting changes in leaves cuticle and chlorophyll content.

  3. STRUCTURAL LEAF CHANGES IN TREES AROUND A SUBWAY AIR DUCT

    Directory of Open Access Journals (Sweden)

    Renato de Aragão Ribeiro Rodrigues

    2015-06-01

    Full Text Available ABSTRACTWhile a number of papers have shown that subway systems have an impact on the air quality through the release of particulate matters, no information about the impact of such particles on tree attributes is available. Tree leaves from three different species from the exit side of a subway station in Rio de Janeiro, Brazil, were more asymmetrical than leaves from the entrance side. This leaves also presenting changes in leaves cuticle and chlorophyll content.

  4. Phase change - memory materials - composition, structure, and properties

    Czech Academy of Sciences Publication Activity Database

    Frumar, M.; Frumarová, Božena; Wágner, T.; Hrdlička, M.

    2007-01-01

    Roč. 18, suppl.1 (2007), S169-S174 ISSN 0957-4522. [International Conference on Optical and Optoelectronic Properties of Materials and Applications 2006. Darwin, 16.06.2006-20.06.2006] R&D Projects: GA ČR GA203/06/0627 Institutional research plan: CEZ:AV0Z40500505 Keywords : phase change memory Subject RIV: CA - Inorganic Chemistry Impact factor: 0.947, year: 2007

  5. Forecasting Long Memory Series Subject to Structural Change

    DEFF Research Database (Denmark)

    Dias, Gustavo Fruet; Papailias, Fotis

    A two-stage forecasting approach for long memory time series is introduced. In the first step we estimate the fractional exponent and, applying the fractional differencing operator, we obtain the underlying weakly dependent series. In the second step, we perform the multi-step ahead forecasts...... for the weakly dependent series and obtain their long memory counterparts by applying the fractional cumulation operator. The methodology applies to stationary and nonstationary cases. Simulations and an application to seven time series provide evidence that the new methodology is more robust to structural...

  6. Option chain and change management : a structural equation application.

    OpenAIRE

    Thierry Burger-Helmchen

    2006-01-01

    The aim of this work is to establish empirically with a structural equation model (SEM) the existence of links between the options perceived by the members of an industry, the expectation of future rents produced by the exercise of these options and firm or industry specific factors. The theoretical part of this work is based on the notion of option chain developed by Bowman and Hurry (1993). The empirical part is on the video-game industry. A questionnaire based dataset on 211 video-game cre...

  7. The influence of drawing speed on structure changes in high carbon steel wires

    Directory of Open Access Journals (Sweden)

    M. Suliga

    2015-01-01

    Full Text Available In the paper the influence of the drawing speed on structure changes has been assessed. The Scanning Electron Microscope investigation confirmed that for wires drawn with high total draft, exceeding 80 %, makes it impossible to clearly assess the impact of drawing technology on structural changes in the drawn wires. Thus, to assess the structural changes necessary to apply quantitative methods. On the basis of examination of the wire structure by measuring of electrical resistance, the structure changes in drawn wires has been determined. It has been shown that the increase of drawing speed, especially above 15 m/s, causes an increase in structure defect, with a decline in platelet orientation of cementite in drawn wires.

  8. Molecular structural changes of plasticized PVC after UV light exposure.

    Science.gov (United States)

    Hankett, Jeanne M; Collin, William R; Chen, Zhan

    2013-12-19

    Plasticized poly(vinyl chloride) (PVC) materials for industrial, medical, and household use are often intentionally exposed to UV light, though its impact on the molecular integrity and toxicity of the surface and bulk of PVC materials is still not well understood. This paper investigates the surface and bulk molecular changes of plasticized PVC films with 25, 10, or 0 wt % bis-2-ethylhexyl phthalate (DEHP) plasticizer after exposure to short wave (254 nm) or long wave (365 nm) UV light. Surface analytical techniques including sum frequency generation vibrational spectroscopy (SFG) revealed short wave UV exposure induced major molecular changes on the plasticized PVC surfaces, resulting in increased surface hydrophilicity and decreased CH3 content with increasing exposure time. Additionally, it was deduced from multiple techniques that the surface and the bulk of the plastic exposed to short wave UV contained phthalic monoesters and phthalic acid formed from multistep radical reactions. In contrast, when exposed to long wave UV, molecular content and ordering on the surfaces of the plastic remained relatively unchanged and the introduction of DEHP in plastic helped protect PVC chains from degradation. Results from this study demonstrate short wave UV exposure will result in plastic surfaces containing phthalates and phthalate-related products accessible to contact by living organisms.

  9. Pathway to psychological change from the structural stability theory.

    Science.gov (United States)

    Cerf, Roger

    2015-01-01

    We show that a path not yet considered exists in the parameter space of the cusp catastrophe that constitutes a 'target-trajectory,' along which psychological change may be achieved in a variety of situations by taking advantage of the protagonists' resistance. The parameters Pathogen - the pathogenic agent - and Therapy, or Dissent and Remedy, are used depending on whether the theory is applied to psychotherapy or conflict, respectively. This proposed target-trajectory offers: (a) conditions optimised in therapy with regard to the intrinsic limitations for the reduction of a patient's pathogenic agent, and in conflict with regard to the 'red-lines' of the protagonists, and (b) the benefit of a step of rapid decrease in the potential barrier to change. Questions raised concern the benefit that a patient may obtain from performing his cognitive task in psychotherapy with minimal requirement for the reduction of his pathogen, and the role that a step of rapid decrease in a potential barrier may play in decision-making, in particular when it comes to end a conflict. The argument is developed in detail for psychoanalytic resistance, relying on principles and procedures described in numerous texts of psychoanalysis. The theory deals with scaling laws - power laws - rather than strict equalities.

  10. Changes in retinal structure and function of Alzheimer's patients

    Directory of Open Access Journals (Sweden)

    Xi Qin

    2017-10-01

    Full Text Available Alzheimer's disease(AD, a neurodegenerative disease, can result in memory loss,cognitive and behavioral deficits. The pathological hallmarkes are β amyloid plaques and neurofibrillary tangles which lead loss of neurons in brain. As the extension of the central nervous system, retina has a similar tissue anatomy with central nervous system. The β amyloid plaques have also been detected in retina of AD. Furthermore, according to eye examinations of AD patients, we have found the loss of retinal ganglion cells, the attenuation of retinal nerve fiber layer thickness, the smaller changes of macula lutea, the decline of vascular density and so on. And then, there occurs the visual field loss and the decline of contrast sensitivity and so on in AD patients. Thus, the retina has occurred nerve degenerative changes in AD. Meanwhile, there has been proved that the retina nerve degeneration is even earlier than senile plaques formation in brain. In addition,curcumin, a natural and safe fluorescent dye, can be used to label β amyloid plaques in retina. The above suggests that retina can be a window for the early diagnosis of AD.

  11. Structural changes of fat tissue after nonaspirative ultrasonic hydrolipoclasy

    Directory of Open Access Journals (Sweden)

    Fúlvio B Godoy

    2011-01-01

    Full Text Available Background: Hydrolipoclasy is an alternative technique less invasive than liposuction. Hydrolipoclasy uses normal saline or hypotonic solution and ultrasound waves that act directly on local adiposity. In the literature there are few reports of morphostructural changes on adipose tissue. Materials and Methods: This study was aimed to evaluate the amount of fat cells injured immediately after treatment and after three days and also cell migration to the area treated using 8 pigs as experimental models, as well as cellular changes by transmission electron microscopy (TEM. Results: The Wilcoxon test was conducted, and a difference was found between the treated side and the corresponding control side on the number of viable cells. The treated side showed a smaller number of viable cells compared to the control side both immediately after treatment and 3 days later. Also occurring 3 days after treatment was the migration of lymphoid cells and fibroblasts, which shows the local inflammatory process and conjunctive neoformation. Soon after treatment there was fluid accumulation within adipocytes. Conclusions: The results shown in this paper demonstrate Ultrasonic Hydrolipoclasy as a viable alternative for the treatment of localized fat deposits without the side effects of traditional surgical procedures. Better results are expected when hypotonic solution is used, since it penetrates into the cell.

  12. 7 CFR 3560.405 - Borrower organizational structure or ownership interest changes.

    Science.gov (United States)

    2010-01-01

    ...) Organizational structure and ownership documentation must include the following items: (i) A current organization... 7 Agriculture 15 2010-01-01 2010-01-01 false Borrower organizational structure or ownership... Servicing § 3560.405 Borrower organizational structure or ownership interest changes. (a) General. The...

  13. Structural changes in data communication in wireless sensor networks

    Science.gov (United States)

    da Silva Cabral, Raquel; Aquino, Andre L. L.; Frery, Alejandro C.; Rosso, Osvaldo A.; Ramírez, Jaime A.

    2013-12-01

    Wireless sensor networks are an important technology for making distributed autonomous measures in hostile or inaccessible environments. Among the challenges they pose, the way data travel among them is a relevant issue since their structure is quite dynamic. The operational topology of such devices can often be described by complex networks. In this work, we assess the variation of measures commonly employed in the complex networks literature applied to wireless sensor networks. Four data communication strategies were considered: geometric, random, small-world, and scale-free models, along with the shortest path length measure. The sensitivity of this measure was analyzed with respect to the following perturbations: insertion and removal of nodes in the geometric strategy; and insertion, removal and rewiring of links in the other models. The assessment was performed using the normalized Kullback-Leibler divergence and Hellinger distance quantifiers, both deriving from the Information Theory framework. The results reveal that the shortest path length is sensitive to perturbations.

  14. Temperature influence on structural changes of foundry bentonites

    Science.gov (United States)

    Holtzer, Mariusz; Bobrowski, Artur; Żymankowska-Kumon, Sylwia

    2011-10-01

    The results of investigations of three calcium bentonites, activated by sodium carbonate, applied in the foundry industry as binding material for moulding sands, subjected to the influence of high temperatures - are presented in the paper. Investigations were performed by the thermal analysis (TG) method, the infrared spectroscopy (FTIR) method and the modern Cu(II)-TET complex method (used for the determination of the montmorillonite content in bentonite samples). The occurrence of the dehydration process and two-stage dehydroxylation process was confirmed only for bentonite no. 2. This probably indicates that cis- and trans-isomers are present in the octahedric bentonite structure. Tests were performed at temperatures: 500, 550, 700, 900, 1000, 1100, 1200 °C.

  15. SOME STRUCTURAL CHANGES ON THE WAY TOWARDS EUNIVERSITY

    Directory of Open Access Journals (Sweden)

    Wolfram LAASER

    2011-01-01

    Full Text Available In the past eLearning has been introduced by many public universities however a concise IT-strategy was not followed during implementation. Different learning platforms were acquired by different departments and no systematic approach was set up to give support for course development, eTutoring or upgrading and archiving of electronic files. Although contemporary learning management systems had some administrative functions incorporated these data were not integrated with the rest of the universities administrative system. The need to work on integrated solutions offering most of the universities services with "one face to the customer" became obvious. The paper will discuss scenarios to explain the services needed and report on the present discussion about reforming organizational structures and adjusting IT infrastructure to create the future eUniversity.

  16. Age-related changes in grey and white matter structure throughout adulthood

    OpenAIRE

    Giorgio, Antonio; Santelli, Luca; Tomassini, Valentina; Bosnell, Rose; Smith, Steve; De Stefano, Nicola; Johansen-Berg, Heidi

    2010-01-01

    Normal ageing is associated with gradual brain atrophy. Determining spatial and temporal patterns of change can help shed light on underlying mechanisms. Neuroimaging provides various measures of brain structure that can be used to assess such age-related change but studies to date have typically considered single imaging measures. Although there is consensus on the notion that brain structure deteriorates with age, evidence on the precise time course and spatial distribution of changes is mi...

  17. Structures of Community and Democratic Practices in Graduate Teacher Education, Teacher Change, and Linkages Facilitating Change.

    Science.gov (United States)

    Rainer, Julie A.; Guyton, Edith M.

    2001-01-01

    Examined practices in a constructivist graduate teacher education program, documenting changes in teachers and their practice and analyzing connections between program practices and teacher change. Data from field notes, teacher and faculty interviews, classroom observations, faculty ratings of teachers, and artifacts helped develop a model for…

  18. Structural evaluation report of piping and support structure for design-changed hot-water layer system

    International Nuclear Information System (INIS)

    Ryu, Jeong Soo

    1998-05-01

    After hot-water layer system had been installed, the verification tests to reduce the radiation level at the top of reactor pool were performed many times. The major goal of this report is to assess the structural integrity on the piping and the support structures of design-changed hot-water layer system. The piping stress analysis was performed by using ADLPIPE program for the pump suction line and the pump discharge line subjected to dead weight, pressure, thermal expansion and seismic loadings. The stress analysis of the support structure was carried out using the reaction forces obtained from the piping stress analysis. The results of structural evaluation for the pipings and the support structures showed that the structural acceptance criteria were satisfied, in compliance with ASME, subsection ND for the piping and subsection NF for the support structures. Therefore based on the results of the analysis and the design, the structural integrity on the piping and the support structures of design-changed hot-water system was proved. (author). 9 refs., 9 tabs., 14 figs

  19. Caloric Restriction Promotes Structural and Metabolic Changes in the Skin

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Forni

    2017-09-01

    Full Text Available Caloric restriction (CR is the most effective intervention known to enhance lifespan, but its effect on the skin is poorly understood. Here, we show that CR mice display fur coat remodeling associated with an expansion of the hair follicle stem cell (HFSC pool. We also find that the dermal adipocyte depot (dWAT is underdeveloped in CR animals. The dermal/vennule annulus vasculature is enlarged, and a vascular endothelial growth factor (VEGF switch and metabolic reprogramming in both the dermis and the epidermis are observed. When the fur coat is removed, CR mice display increased energy expenditure associated with lean weight loss and locomotion impairment. Our findings indicate that CR promotes extensive skin and fur remodeling. These changes are necessary for thermal homeostasis and metabolic fitness under conditions of limited energy intake, suggesting a potential adaptive mechanism.

  20. Disease related tissue damage and subsequent changes in fillet structure

    DEFF Research Database (Denmark)

    of the fish and subsequent a reduction in price. Despite this, the impact of infectious diseases on the meat quality and the mechanisms behind are poorly investigated. Wound repair is a dynamic, interactive response to tissue injury that involves a complex interaction and cross talk of various cell types......, extracellular matrix molecules, soluble mediators and cytokines. In order to describe the molecular mechanisms and processes of wound repair, a panel of genes covering immunological factors and tissue regeneration were used to measure changes at the mRNA level following mechanical tissue damage in rainbow trout...... (Oncorhynchus mykiss). Needle disrupted muscle tissue was sampled at different time points and subject to real-time RT-PCR for measuring the expression of the genes IL-1β, IL-8, IL-10, TGF-β, Myostatin-1ab, MMP-2, CTGF, Collagen-1α, VEGF, iNOS, Arg-2 and FGF. The results showed an initial phase with up...

  1. Structural changes in the liver in metabolic syndrome

    Directory of Open Access Journals (Sweden)

    D. V. Vasendin

    2015-01-01

    Full Text Available Scientifically proven close relationship of nonalcoholic fatty liver disease with development of metabolic syndrome and its individual components involves the conclusion that the target organ in metabolic symptom, even regardless of the severity of obesity, the liver occupies a dominant position, as the body undergoes the first characteristic of non-alcoholic fatty liver disease changes, involving violation of metabolism in the body. Dislipoproteinemia plays an important role in the formation of metabolic syndrome in obesity and other obesity-associated diseases. Altered liver function are the root cause of violations of processes of lipid metabolism and, consequently, abnormal functioning of the liver may be a separate, additional and independent risk factor for development of dyslipidemia and obesity as the main component of the metabolic syndrome.

  2. Probing structural changes of proteins incorporated into water-in-oil emulsions

    DEFF Research Database (Denmark)

    Jorgensen, Lene; van de Weert, Marco; Vermehren, Charlotte

    2004-01-01

    (BSA) and human serum albumin (HSA) as model proteins. FTIR shows that the overall secondary structure of the proteins changes to some extent, 12% for BSA and 9% for HSA, when these are incorporated into the emulsion. There was no evidence of changes in the distribution of secondary structural elements...... indicated that the domains in the proteins change because the shape of the transition peaks changes, when the proteins were incorporated into the emulsions. The total enthalpy decreases for BSA and HSA when these are incorporated into the emulsion, and some changes to the transition temperatures...

  3. Structural change, land use and the state in China : Making sense of three divergent processes

    NARCIS (Netherlands)

    M. Arsel (Murat); A. Dasgupta (Anirban)

    2010-01-01

    textabstractRapid economic growth involves significant changes in land use patterns. The paper uses the recent history of Chinese economic growth to highlight and interrogate the implication of such changes within the context of structural transformation. It argues that though land use change is an

  4. Structural changes in elastically stressed crystallites under irradiation

    International Nuclear Information System (INIS)

    Zolnikov, K.P.; Korchuganov, A.V.; Kryzhevich, D.S.; Chernov, V.M.; Psakhie, S.G.

    2015-01-01

    The response of elastically stressed iron and vanadium crystallites to atomic displacement cascades was investigated by molecular dynamics simulation. Interatomic interaction in vanadium was described by a many-body potential calculated in the Finnis–Sinclair approximation of the embedded atom method. Interatomic interaction in iron was described by a many-body potential constructed in the approximation of valence-electron gas. The crystallite temperature in the calculations was varied from 100 to 600 K. The elastically stressed state in the crystallites was formed through uniaxial tension by 4–8% such that their volume remained unchanged. The energy of a primary knock-on atom was varied from 0.5 to 50 keV. It is shown that the lower the temperature and the higher the strain degree of an initial crystallite, the lower the threshold primary knock-on atom energy for plastic deformation generation in the crystallite. The structural rearrangements induced in the crystallites by an atomic displacement cascade are similar to those induced by mechanical loading. It is found that the rearrangements are realized through twinning

  5. Early structural changes in sheep lung following thoracic irradiation

    International Nuclear Information System (INIS)

    Guerry-Force, M.L.; Perkett, E.A.; Brigham, K.L.; Meyrick, B.

    1988-01-01

    Using a large animal model of radiation lung injury--the sheep exposed to bilateral thoracic irradiation--we have recently shown the development of sustained pulmonary hypertension during the first 4 weeks following radiation. This is the period prior to the onset of pneumonitis and pulmonary fibrosis. In the present study, we have examined biopsy and autopsy lung tissue from these same sheep and assessed the sequential changes in lung morphology. Six unanesthetized sheep received bilateral thoracic irradiation (a total of 15 Gy); control sheep were sham irradiated. Lung biopsy tissue was taken prior to and at weekly or biweekly intervals during the 4 weeks immediately following radiation. The lungs were also removed at autopsy for light and electron microscopic examination. Our results show early (Week 1) interstitial and progressive intraalveolar edema accompanied by endothelial and epithelial injury. A gradual increase in number of interstitial mononuclear cells was evident from Week 1, both in the lung tissue and in perivascular cuffs. The number of peripheral lung interstitial mononuclear cells was twice baseline from Week 3 and included accumulation of lymphocytes, fibroblasts, and intravascular macrophages. The increased numbers of mononuclear cells paralleled the development of chronic pulmonary hypertension, perhaps suggesting their involvement in the pathogenesis of this disease. Alternatively, it may be that increased mononuclear cell number represents a stage of lung repair

  6. Effects of menopause on brain structural changes in schizophrenia.

    Science.gov (United States)

    Fukuta, Hajime; Ito, Itsuo; Tateno, Amane; Nogami, Tsuyoshi; Taiji, Yasutomo; Arakawa, Ryosuke; Suhara, Tetsuya; Asai, Kunihiko; Okubo, Yoshiro

    2013-01-01

    The aim of this study was to investigate the influences of menopause on brain morphological changes in schizophrenia using magnetic resonance imaging (MRI). Forty female schizophrenia patients, 20 premenopausal and 20 postmenopausal, and 50 female controls underwent cerebral MRI. Optimized voxel-based morphometry was performed with Statistical Parametric Mapping version 5. Compared with controls, regional gray matter reductions in schizophrenia patients were observed in the insula, superior temporal gyrus, anterior cingulate, parahippocampal gyrus, and thalamus. Direct comparison between the patient groups showed that the gray matter of postmenopausal patients was significantly smaller when compared with premenopausal patients in the left middle frontal gyrus, and no region had significantly lower gray matter volume in premenopausal patients relative to postmenopausal patients. Significant negative correlation between gray matter volume and the interval after menopause was found in the right superior frontal gyrus in the postmenopause patient group. Differential morphological alterations between postmenopausal and premenopausal schizophrenia patients were observed, suggesting that the female hormone plays a protective role against schizophrenia. © 2013 The Authors. Psychiatry and Clinical Neurosciences © 2013 Japanese Society of Psychiatry and Neurology.

  7. Early structural changes in sheep lung following thoracic irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Guerry-Force, M.L.; Perkett, E.A.; Brigham, K.L.; Meyrick, B.

    1988-04-01

    Using a large animal model of radiation lung injury--the sheep exposed to bilateral thoracic irradiation--we have recently shown the development of sustained pulmonary hypertension during the first 4 weeks following radiation. This is the period prior to the onset of pneumonitis and pulmonary fibrosis. In the present study, we have examined biopsy and autopsy lung tissue from these same sheep and assessed the sequential changes in lung morphology. Six unanesthetized sheep received bilateral thoracic irradiation (a total of 15 Gy); control sheep were sham irradiated. Lung biopsy tissue was taken prior to and at weekly or biweekly intervals during the 4 weeks immediately following radiation. The lungs were also removed at autopsy for light and electron microscopic examination. Our results show early (Week 1) interstitial and progressive intraalveolar edema accompanied by endothelial and epithelial injury. A gradual increase in number of interstitial mononuclear cells was evident from Week 1, both in the lung tissue and in perivascular cuffs. The number of peripheral lung interstitial mononuclear cells was twice baseline from Week 3 and included accumulation of lymphocytes, fibroblasts, and intravascular macrophages. The increased numbers of mononuclear cells paralleled the development of chronic pulmonary hypertension, perhaps suggesting their involvement in the pathogenesis of this disease. Alternatively, it may be that increased mononuclear cell number represents a stage of lung repair.

  8. Nickel–carbon nanocomposites: Synthesis, structural changes and strengthening mechanisms

    International Nuclear Information System (INIS)

    Nunes, D.; Vilarigues, M.; Correia, J.B.; Carvalho, P.A.

    2012-01-01

    The present work investigates Ni–nanodiamond and Ni–graphite composites produced by mechanical synthesis and subsequent heat treatments. Processing of nickel–carbon nanocomposites by this powder metallurgy route poses specific challenges, as carbon phases are prone to carbide conversion and amorphization. The processing window for carbide prevention has been established through X-ray diffraction by a systematic variation of the milling parameters. Transmission electron microscopy confirmed the absence of carbide and showed homogeneous particle distributions, as well as intimate bonding between the metallic matrix and the carbon phases. Ring diffraction patterns of chemically extracted carbon phases demonstrated that milled nanodiamond preserved crystallinity, while an essentially amorphous nature could be inferred for milled graphite. Raman spectra confirmed that nanodiamond particles remained largely unaffected by mechanical synthesis, whereas the bands of milled graphite were significantly changed into the typical amorphous carbon fingerprint. The results on the annealed nanocomposites showed that milling with Ni accelerated graphitization of the carbon phases during heat treatments at 973 and 1073 K in both composites. At the finer scales, the nanocomposites exhibited a remarkable microhardness enhancement (∼70%) compared with pure nanostructured nickel. The Hall–Petch relation and the Orowan–Ashby equation are used to discuss strengthening mechanisms and the load transfer ability to the reinforcing particles.

  9. CHLOROPLAST STRUCTURAL AND FUNCTIONAL CHANGES AS BIOMARKERS OF HEAVY METAL CONTAMINATION

    Directory of Open Access Journals (Sweden)

    M. V.

    2016-02-01

    Full Text Available The aim was to confirm the hypothesis of possibility to use the chloroplast structural and functional changes in higher plants as biomarkers to assess heavy metal contamination. Chloroplast ultra-structural changes of Pisum sativum L were detected using the transmission electron microscopy. This work deals with studies of chloroplast structure responses to a high content of copper (250 μmМ and zinc (400 μmМ. Data on changes in the structure of chloroplasts in particular, heterogeneity in the grain thylakoid packing, increase of interthylakoid gaps and thickness of chloroplast grain thylakoids in comparison with controls were obtained. The results of studies on structural and functional chloroplasts changes offer challenges for their use as markers for an early diagnostics of abiotic stress effects and in biotechnological studies to produce novel advanced varieties of crops resistant to stress.

  10. Structure changes, the contribution of sectors, income per capita Indonesia in 1990 – 2014

    Directory of Open Access Journals (Sweden)

    Paulina Harun

    2017-03-01

    Full Text Available Economic development is seen as a process of transition from one phase to another, from simple economic structure (agriculture to the modern economy structure. Economic development is characterized by changes in the structure of the agricultural sector into the modern sector. The changes affect all the matters related thereto. Therefore, a change or transformation of economic activity is referred to as a structural change. This study aims to analyze the structural changes in the national product, and the factors that cause changes in the structure and level of sectoral imbalances as a result of the structural changes. The study was conducted by using the economic sector, divided into four major groups, namely the primary, secondary, utilities and services from 1990 to 2014. Secondary data were collected by the method of sectoral trends, models Chanery Syrquin-Barua, Theil index. The results showed that the sectoral trend has a positive result such as utilities and services sectors, while the primary and secondary sectors tend to be negative. From the model Chenery, Syrquin-Barua shows the per capita income has a positive effect on the primary sector and the utilities, residents have positive effect on the secondary sector, utilities and services. Meanwhile dummy variable has a positive effect on the primary sector, secondary and services. Sectoral inequality occurs in the secondary sector.

  11. Brain structural changes following adaptive cognitive training assessed by Tensor-Based Morphometry (TBM).

    Science.gov (United States)

    Colom, Roberto; Hua, Xue; Martínez, Kenia; Burgaleta, Miguel; Román, Francisco J; Gunter, Jeffrey L; Carmona, Susanna; Jaeggi, Susanne M; Thompson, Paul M

    2016-10-01

    Tensor-Based Morphometry (TBM) allows the automatic mapping of brain changes across time building 3D deformation maps. This technique has been applied for tracking brain degeneration in Alzheimer's and other neurodegenerative diseases with high sensitivity and reliability. Here we applied TBM to quantify changes in brain structure after completing a challenging adaptive cognitive training program based on the n-back task. Twenty-six young women completed twenty-four training sessions across twelve weeks and they showed, on average, large cognitive improvements. High-resolution MRI scans were obtained before and after training. The computed longitudinal deformation maps were analyzed for answering three questions: (a) Are there differential brain structural changes in the training group as compared with a matched control group? (b) Are these changes related to performance differences in the training program? (c) Are standardized changes in a set of psychological factors (fluid and crystallized intelligence, working memory, and attention control) measured before and after training, related to structural changes in the brain? Results showed (a) greater structural changes for the training group in the temporal lobe, (b) a negative correlation between these changes and performance across training sessions (the greater the structural change, the lower the cognitive performance improvements), and (c) negligible effects regarding the psychological factors measured before and after training. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Interplay between past market correlation structure changes and future volatility outbursts

    Science.gov (United States)

    Musmeci, Nicoló; Aste, Tomaso; Di Matteo, T.

    2016-11-01

    We report significant relations between past changes in the market correlation structure and future changes in the market volatility. This relation is made evident by using a measure of “correlation structure persistence” on correlation-based information filtering networks that quantifies the rate of change of the market dependence structure. We also measured changes in the correlation structure by means of a “metacorrelation” that measures a lagged correlation between correlation matrices computed over different time windows. Both methods show a deep interplay between past changes in correlation structure and future changes in volatility and we demonstrate they can anticipate market risk variations and this can be used to better forecast portfolio risk. Notably, these methods overcome the curse of dimensionality that limits the applicability of traditional econometric tools to portfolios made of a large number of assets. We report on forecasting performances and statistical significance of both methods for two different equity datasets. We also identify an optimal region of parameters in terms of True Positive and False Positive trade-off, through a ROC curve analysis. We find that this forecasting method is robust and it outperforms logistic regression predictors based on past volatility only. Moreover the temporal analysis indicates that methods based on correlation structural persistence are able to adapt to abrupt changes in the market, such as financial crises, more rapidly than methods based on past volatility.

  13. Vulnerability of roads and associated structures to the effects of climate change

    International Nuclear Information System (INIS)

    Arisz, H.; Therrien, M.; Burrell, B.C.; LeBlanc, M.M.

    2009-01-01

    The vulnerability of roads and associated structures in the City of Greater Sudbury to the effects of climate change was evaluated using the Public Infrastructure Vulnerability Committee (PIEVC) Engineering Protocol for Climate Change Infrastructure Assessment. Study objectives were to evaluate the vulnerability of road-related infrastructure in Greater Sudbury to climate change, and to identify potential impediments to the application of the protocol in other municipalities. Based on the experience gained during this study, recommendations were provided with respect to the vulnerabilities of roads and associated structures to the predicted effects of climate change and the performance of vulnerability assessments. (author)

  14. The role of organizational structure in readiness for change: A conceptual integration.

    Science.gov (United States)

    Benzer, Justin K; Charns, Martin P; Hamdan, Sami; Afable, Melissa

    2017-02-01

    The purpose of this review is to extend extant conceptualizations of readiness for change as an individual-level phenomenon. This review-of-reviews focuses on existing conceptual frameworks from the dissemination, implementation, quality improvement, and organizational transformation literatures in order to integrate theoretical rationales for how organization structure, a key dimension of the organizational context, may impact readiness for change. We propose that the organization structure dimensions of differentiation and integration impact readiness for change at the individual level of analysis by influencing four key concepts of relevance, legitimacy, perceived need for change, and resource allocation. We identify future research directions that focus on these four key concepts.

  15. Assessing the impact of structural changes in the financial sector on ...

    African Journals Online (AJOL)

    institution relationship by means of a Financial Social Accounting Matrix multipliers model for the case of Algeria. Our purpose is to understand the role of structural institutional changes implemented in the financial sector and their contribution to ...

  16. Activists and incumbents structuring change: The interplay of agency, culture, and networks in field evolution

    NARCIS (Netherlands)

    van Wijk, J.J.; Stam, W.; Elfring, T.; Zietsma, C.; den Hond, F.

    2013-01-01

    We examine organizational field change instigated by activists. Contrary to existing views emphasizing incumbent resistance, we suggest that collaboration between incumbents and challenger movements may emerge when a movement's cultural and relational fabric becomes moderately structured, creating

  17. STRUCTURAL CHANGES OF THE HEART DURING SEVERE SEPSIS OR SEPTIC SHOCK

    NARCIS (Netherlands)

    Smeding, Lonneke; Plotz, Frans B.; Groeneveld, A. B. Johan; Kneyber, Martin C. J.

    Cardiovascular dysfunction is common in severe sepsis or septic shock. Although functional alterations are often described, the elevated serum levels of cardiac proteins and autopsy findings of myocardial immune cell infiltration, edema, and damaged mitochondria suggest that structural changes to

  18. Autolysis control and structural changes of purified ficin from Iranian fig latex with synthetic inhibitors.

    Science.gov (United States)

    Zare, H; Moosavi-Movahedi, A A; Salami, M; Sheibani, N; Khajeh, K; Habibi-Rezaei, M

    2016-03-01

    The fig's ficin is a cysteine endoproteolytic enzyme, which plays fundamental roles in many plant physiological processes, and has many applications in different industries such as pharmaceutical and food. In this work, we report the inhibition and activation of autolysis and structural changes associated with reaction of ficin with iodoacetamide and tetrathionate using high-performance liquid chromatography (HPLC), ultra filtration membrane, and dynamic light scattering (DLS) methods. The ficin structural changes were also determined using UV-absorption, circular dichroism (CD), fluorescence spectroscopy, and differential scanning calorimetry (DSC) techniques. These techniques demonstrated that iodoacetamide completely inhibited ficin autolysis, which was irreversible. However, tetrathionate partially and reversibility inhibited its autolysis. The ficin structural changes with two synthetic inhibitors were associated with secondary structural changes related to decreased alpha-helix and increased beta sheet and random coil conformations, contributing to its aggregation. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Structural Integrity Evaluation of Cold Neutron Laboratory Building by Design Change of Guide Shielding Room

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Sangik; Kim, Youngki; Kim, Harkrho

    2007-06-15

    This report summarizes the results of the structural integrity evaluation for the cold neutron laboratory building by design change of guide shielding room. The design of the guide shielding room was changed by making its structure members in normal concrete (2.3 g/cc) instead of heavy concrete (3.5 g/cc) because the heavy concrete could be not supplied to meet its design specification. Therefore, it was decided that the guide shielding room is made of the normal concrete. And, the shielding performance of the normal concrete was recalculated to confirm satisfying its design specification, which is of a 9000 zone according to HANARO radiation region classification. The change makes the shielding wall thicker than existing design, and then it is caused to qualify the structural integrity evaluation of the CNLB. Finally, the structural integrity of the CNLB was re-evaluated by considering the design change of the guide shielding room.

  20. Neuroadaptive Changes Associated with Smoking: Structural and Functional Neural Changes in Nicotine Dependence

    Directory of Open Access Journals (Sweden)

    Chantal Martin-Soelch

    2013-02-01

    Full Text Available Tobacco smoking is the most frequent form of substance abuse. We provide a review of the neuroadaptive changes evidenced in human smokers with regard to the current neurobiological models of addiction. Addiction is thought to result from an interplay between positive and negative reinforcement. Positive reinforcing effects of the drugs are mediated by striatal dopamine release, while negative reinforcement involves the relief of withdrawal symptoms and neurobiological stress systems. In addition, drug-related stimuli are attributed with excessive motivational value and are thought to exert a control on the behavior. This mechanism plays a central role in drug maintenance and relapse. Further neuroadaptive changes associated with chronic use of the drug consist of reduced responses to natural rewards and in the activation of an antireward system, related to neurobiological stress systems. Reduced inhibitory cognitive control is believed to support the development and the maintenance of addiction. The findings observed in human nicotine dependence are generally in line with these models. The current state of the research indicates specific neuroadaptive changes associated with nicotine addiction that need to be further elucidated with regard to their role in the treatment of nicotine dependence.

  1. Solidarity as an Engine for Economic Change – The Impact of Swedish and US Political Ideology on Wage Differentials and Structural Change

    DEFF Research Database (Denmark)

    Wulfgramm, Melike

    This paper investigates the impact of interindustry wage distribution on structural change in the Swedish and US manufacturing sector in the 1970s. Structural change in the centralized Swedish labour market reacts far more positive to market pressures towards wage changes than structural change i...... in the decentralized US labour market. Support for the Rehn-Meidner model of solidarity wages and structural change is found. It is shown how opposing ideologies and policy making influence not only the wage pattern but also industry structures of economies....

  2. Technological Progress, Structural Change and Productivity Growth in Manufacturing Sector of South Korea

    OpenAIRE

    Singh, Lakhwinder

    2004-01-01

    This paper focuses on the impact of technology, structural change on the aggregate productivity growth in manufacturing sector of South Korea, using the eight firm size classes over the period 1970-2000. The conventional shift-share analysis is used to measure the impact of shift of both labor and capital inputs. The results show that structural change on average has been conducive to productivity growth during the 1970s and this pattern reversed afterwards. Small and medium industries were m...

  3. Continuous Record Laplace-based Inference about the Break Date in Structural Change Models

    OpenAIRE

    Casini, Alessandro; Perron, Pierre

    2018-01-01

    Building upon the continuous record asymptotic framework recently introduced by Casini and Perron (2017a) for inference in structural change models, we propose a Laplace-based (Quasi-Bayes) procedure for the construction of the estimate and confidence set for the date of a structural change. The procedure relies on a Laplace-type estimator defined by an integration-based rather than an optimization-based method. A transformation of the leastsquares criterion function is evaluated in order to ...

  4. Structural Changes in the Middle East Stock Markets: The case of Israel and Arab Countries

    OpenAIRE

    Marashdeh, Hazem; Wilson, E.J.

    2005-01-01

    This paper tests for structural changes in the price indices of four stock markets in the Middle East region, namely, Egypt, Turkey Jordan, Morocco and Israel. The Innovational Outlier (IO) model and Additive Outlier (AO) model indicate that all variables show evidence of non-stationarity, I(1), even with structural change. Moreover, the coefficients for all dummy variables such as intercept, slope and time of the break are found to be significant and all have the right signs. The endogenousl...

  5. Structural Changes Following Velopharyngeal Resistance Training (Continuous Positive Airway Pressure Therapy): A Preliminary Report.

    Science.gov (United States)

    Bae, Youkyung; Pfeil, Gwenlyn

    2018-01-01

    To evaluate the feasibility/effectiveness of using magnetic resonance imaging (MRI) to document velopharyngeal (VP) structural changes induced by continuous positive airway pressure (CPAP) therapy. Changes in velar length and thickness, levator veli palatini (LVP) length and thickness, velar volume, and intravelar muscular proportion along the course of CPAP therapy participation (Pre-CPAP, Post-CPAP, and withdrawal). Velar and LVP lengths remained nearly the same, with the median changes (Δ) less than 0.6%, across repeated conditions. Although varying in magnitudes of change, median velar volume (Δ4%), velar thickness (Δ20%), LVP thickness (Δ17%), and intravelar muscular proportion (Δ10%) illustrated a consistent pattern of increases following the 8-week CPAP therapy. These VP structural measurements slightly decreased but remained above the pretraining condition after 8-week detraining. This report successfully demonstrated that MRI is a viable tool to document CPAP therapy-induced VP structural changes while providing preliminary empirical data.

  6. Organizational models as configurations of structure, culture, leadership, control, and change strategy

    Directory of Open Access Journals (Sweden)

    Janićijević Nebojša

    2017-01-01

    Full Text Available Starting from the axioms of consistency, stability, contingency, and configuration, research on organizational structure, culture, control, leadership, and change management strategy has shown that their typical configurations, or models, can be differentiated according to the same two criteria: distribution of power and dominant organizational dimension. On the one hand there are models of structure, culture, control, leadership, and change management strategy that are based on an unequal, or authoritarian, distribution of power within organizations, while on the other hand there are models that are based on democratic, or equal, distribution of power. Also, on the one hand there are models of structure, culture, control, leadership, and change strategy that are based on work structure and tasks, while on the other hand there are models of these organizational components that are based on social structure, people, and their relationships. Harmonization of typical configurations of organizational structure, culture, control, leadership, and change strategy occurs due to the harmonization of the differentiation criteria. Based on this harmonization, four organizational models have been identified as typical configurations of structure, culture, control, leadership, and change strategy: the autocratic, bureaucratic, innovative, and task models. Each of these models is effective in a different environmental contingency.

  7. Exploring energy efficiency in several European countries. An attribution analysis of the Divisia structural change index

    International Nuclear Information System (INIS)

    Fernández González, P.

    2015-01-01

    Highlights: • We present a new attribution analysis approach to study structural change index. • Based on LMDI method, we decompose changes in AEI in the EU in 1995–2010. • Mild AEI drop as a result of structural change, particularly in Eastern economies. • Transport, hotels and restaurants: positive contributors, specifically in Western EU. • Strategies should be focused on Industry: the most influential sector in reducing AEI. - Abstract: This paper aims at exploring the influence that the changes in sectoral composition in most EU economies have had on aggregate energy intensity. We rely on the so-called Logarithmic Mean Divisia Index (LMDI) method, implemented within a multiplicative energy intensity approach. Then, based on the Index Decomposition Analysis (IDA), we present, develop and apply a new methodology that enables the exploration of the contribution of each sector to the percent change in the structural factors index. Our findings show: (a) a greater importance of the intensity factor over the structural one, (b) a positive influence of structural change in some ex-communist countries, and (c) a strong, negative contribution of the industrial sector (including construction) to changes in aggregate energy intensity in most European economies, particularly in the Western ones. In short, adaptation to more efficient techniques, innovation, R and D, and substitution for higher quality energies, seem to be the action lines to follow, although in former communist countries these strategies should be accompanied by other policies aiming at accelerating the transition processes

  8. How social structure changes in Chinese global cities: Synthesizing globalization, migration and institutional factors in Beijing

    NARCIS (Netherlands)

    Shi, Q.; Liu, T.; Musterd, S.; Cao, G.

    2017-01-01

    Recent studies on the social structural change in global cities have recognized globalization, migration, and institutional factors as three main forces underlying this process. However, effects of these factors have rarely been synthetically examined and the social structure of emerging Chinese

  9. Structure, Agency and the Role of Values in Processes of Institutional Change

    NARCIS (Netherlands)

    Dolfsma, Wilfred; Verburg, Rudi

    2008-01-01

    Research on institutional change has flourished ever since the debate on agency and structure has moved away from the previously uncompromising positions in which either agency or structure was emphasized. A conceptual compromise is Sought here in a focus On the processes of institutionalization,

  10. Structural Changes in Deformed Soft Magnetic Ni-Based Metallic Glass

    NARCIS (Netherlands)

    Jurikova, A.; Csach, K.; Miskuf, J.; Ocelik, V.

    The effects of intensive plastic deformation of the soft magnetic metallic glass Ni Si 13 on the structural relaxation were examined. The enthalpy changes studied by differential scanning calorimetry revealed that the intensive plastic deformation was associated with the partial structural

  11. Inositol-P6 induced structural changes in duck major haemoglobin

    African Journals Online (AJOL)

    Bamiji Babalola

    2011-11-02

    Nov 2, 2011 ... E-mail: solababarinde@yahoo.com Tel: +2348037232934. molecule in solution, hence this study. Structural changes in solution are not only affected by allosteric effectors ... and structural properties (Shibayama and Saigo, 1995, .... haemoglobin solution was placed on a glass rod, one end of which.

  12. The Structural Changes in the Economy of Ukraine and its Energy Intensity

    Directory of Open Access Journals (Sweden)

    Kyzym Mykola O.

    2017-12-01

    Full Text Available The article is concerned with an analysis of structural changes in the economy of Ukraine in view of energy intensity of types of economic activity (TEA. On considering the main tendencies of development of Ukraine’s economy in 2000 – 2015, it has been proved that, unlike the world economy, its development is of more unevenly nature. In order to research structural changes in the domestic economy in the period from 2000 to 2015, the methodical approach consisting of a number of interconnected stages has been proposed. Using this approach: the structure of economy of Ukraine by TEA has been analyzed, the classification and structure of the TEA distribution by their importance have been suggested; the dynamics of TEA of Ukraine have been analyzed, the classification and structure of distribution of Ukraine’s TEA by dynamics of development has been proposed; a matrix of positioning of the TEA of Ukraine in the plane of «proportion – rate of change» has been built; the values have been calculated and directions of structural changes of TEA in economy of Ukraine have been defined; a characterization of the TEA of economy of Ukraine as to the degree of materiality of structural shift has been formed; the integral coefficients of structural shifts in economy for the studied period have been calculated; the classification of the TEA of Ukraine according to the level of energy intensity has been developed, the structure of economy by the energy intensity groups has been presented; the indices have been calculated and directions of structural shifts of groups with different energy intensity of TEA have been determined; the integral coefficients of structural shift of economy due to the groups of TEA with different energy intensity have been calculated; the general characterization of structural shifts of the TEA of Ukraine in 2000 – 2015 has been formed.

  13. [Atrial fibrillation as consequence and cause of structural changes of atria].

    Science.gov (United States)

    Aparina, O P; Chikhireva, L N; Stukalova, O V; Mironova, N A; Kashtanova, S Iu; Ternovoĭ, S K; Golitsyn, S P

    2014-01-01

    Changes of atrial structure and function are the contributors of atrial fibrillation clinical course, complications and treatment effectiveness. Effects of inflammation and mechanical stretch on atrial structural remodeling leading to atrial fibrillation are reviewed in the article. Contemporary invasive and non-invasive methods of evaluation (including late gadolinium enhancement magnetic resonance imaging) of patients with atrial structural remodeling in atrial fibrillation are also described.

  14. Structure changes of natively disordered Humanin in the presence of lipid

    OpenAIRE

    Hirano, Atsushi; Shiraki, Kentaro; Niikura, Takako; Arakawa, Tsutomu; Kita, Yoshiko

    2010-01-01

    While neuroprotective activities of Humanin peptides have been clearly demonstrated, the functional mechanism has not been fully understood. Humanin and a majority of Humanin analogs showed a disordered structure at low peptide concentrations and aggregation at higher concentrations in aqueous solution at pH 7.0. Here we have examined the structure in lipid environments, i.e., in the presence of liposome by circular dichroism. Humanin underwent a large structure change into a typical β-sheet...

  15. The Networked University: The Structure, Culture, and Policy of Universities in a Changing Environment

    Science.gov (United States)

    de Wit, Kurt

    2010-01-01

    The universities in Europe are finding themselves in a turbulent environment. They are exposed to global and European developments. This article links changes in the structure, culture, and policy of universities to these developments and changes in the broader-than-national environment. The central question is, in short: what is globalisation…

  16. Acetylcholinesterase in motion : Visualizing conformational changes in crystal structures by a morphing procedure

    NARCIS (Netherlands)

    Zeev-Ben-Mordehai, T; Silman, I.; Sussman, J.L.

    In order to visualize and appreciate conformational changes between homologous three-dimensional (3D) protein structures or protein/inhibitor complexes, we have developed a user-friendly morphing procedure. It enabled us to detect coordinated conformational changes not easily discernible by analytic

  17. Cognitive Structures of University Students about Environmental Education, Climate Change and Consumption Concepts

    Science.gov (United States)

    Keles, Özgül; Gilbertson, Kenneth L.; Uzun, Naim

    2016-01-01

    The purpose of this study was to determine cognitive structures and the retention of knowledge about environmental education, climate change and consumption concepts. The field of Environmental Education is increasingly including both climate change and consumption in the context of sustainability. Thus, this research is investigating the…

  18. Structure changes of natively disordered Humanin in the presence of lipid.

    Science.gov (United States)

    Hirano, Atsushi; Shiraki, Kentaro; Niikura, Takako; Arakawa, Tsutomu; Kita, Yoshiko

    2010-04-01

    While neuroprotective activities of Humanin peptides have been clearly demonstrated, the functional mechanism has not been fully understood. Humanin and a majority of Humanin analogs showed a disordered structure at low peptide concentrations and aggregation at higher concentrations in aqueous solution at pH 7.0. Here we have examined the structure in lipid environments, i.e., in the presence of liposome by circular dichroism. Humanin underwent a large structure change into a typical beta-sheet structure at neutral pH in the presence liposome made of a negatively charged 1,2-dioleoyl-sn-glycero-3-phosphoglycerol (DOPG), but not an electrically neutral 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC). As Humanin possesses a positive charge at neutral pH, the observed structure changes with DOPG suggest electrostatic binding of the peptide with the lipid. No effect of NaCl on the Humanin structure was observed in neutral solution and in the presence of DOPC liposome. Increasing temperature resulted in changes in the structure due to aggregation. On the other hand, the effects of temperature on the Humanin structure showed that it has a relatively stable structure in the presence of DOPG liposome independent of the presence of NaCl. Copyright 2010 Elsevier B.V. All rights reserved.

  19. Stable isotope evidence of long-term changes in North Sea food web structure

    DEFF Research Database (Denmark)

    Richardson, Katherine; Christensen, Jens Tang

    2008-01-01

    coast. Porpoises collected after ~1960 had significantly lower d15N than porpoises collected earlier. This change in d15N implies that fundamental changes in food web structure in, or nutrient availability to, the North Sea have taken place over the last ~150 yr and that most of the change occurred over...... reported here may be a reflection of a change in the isotope signature of nitrogen entering the food web. Regardless of its underlying cause, the recorded change in isotopic signature in harbour porpoises is noteworthy as it represents the first fisheries-independent documentation of a long-term temporal...

  20. Protein structure change studied by hydrogen-deuterium exchange, functional labeling, and mass spectrometry

    Science.gov (United States)

    Englander, Joan J.; Del Mar, Charyl; Li, Will; Englander, S. Walter; Kim, Jack S.; Stranz, David D.; Hamuro, Yoshitomo; Woods, Virgil L.

    2003-01-01

    An automated high-throughput, high-resolution deuterium exchange HPLC-MS method (DXMS) was used to extend previous hydrogen exchange studies on the position and energetic role of regulatory structure changes in hemoglobin. The results match earlier highly accurate but much more limited tritium exchange results, extend the analysis to the entire sequence of both hemoglobin subunits, and identify some energetically important changes. Allosterically sensitive amide hydrogens located at near amino acid resolution help to confirm the reality of local unfolding reactions and their use to evaluate resolved structure changes in terms of allosteric free energy. PMID:12773622

  1. Ultra-Structural Changes of the Early Childhood Caries Starting Phases of Development

    Directory of Open Access Journals (Sweden)

    Kokoceva-Ivanovska Olga

    2014-03-01

    Full Text Available In the recent 20 years, besides dramatic reduction of caries in many countries where complex programme of prevention is carried out, prevalence of Early Childhood Caries (ECC has expressed continual growth trend. The aim of our research was to determine precisely ultra-structural changes in the enamel substance at the initial lesion of the ECC (white spot lesion, as initial change of great importance for its preventive aspect. Therefore, we directed our experiment to evaluate ultra-structural changes of the teeth enamel in primary teeth with circular caries in its opening stages of development: initial caries lesion and superficial form.

  2. The Condition of and Structural Changes in the Energy Sector of Ukraine

    Directory of Open Access Journals (Sweden)

    Miliutin Hlib V.

    2017-12-01

    Full Text Available The article is dedicated to the analysis of the condition of Ukraine’s energy sector and its structural changes in the period 2000-2016. The dynamics of electric power production in Ukraine and the world, as well as the capacity utilization factor are studied. There analyzed the structure of capacities and electric power production in Ukraine by types of generation: those of thermal power plants, nuclear power plants, combined heat and power plants, hydroelectric power plants, and renewable energy sources. The lifetime of the existing capacities is studied. Structural changes in the capacities and electric power production in Ukraine are investigated. It is proven that a tendency to reduce the electric power production in Ukraine, with a simultaneous increase in the world production, was observed; and that most of production capacities in the nuclear, thermal and hydropower sector have expired their design lifetime and require replacement or modernization. It is determined that the structural changes in capacities and electric power production in Ukraine in the period 2000-2016 were very low with the largest structural change in capacities and electric power production in the period under review taking place in the production of electricity from renewable energy sources, and a significant negative structural change – in the production of electricity in thermal power plants.

  3. Social structure, infectious diseases, disasters, secularism, and cultural change in America.

    Science.gov (United States)

    Grossmann, Igor; Varnum, Michael E W

    2015-03-01

    Why do cultures change? The present work examined cultural change in eight cultural-level markers, or correlates, of individualism in the United States, all of which increased over the course of the 20th century: frequency of individualist themes in books, preference for uniqueness in baby naming, frequency of single-child relative to multichild families, frequency of single-generation relative to multigeneration households, percentage of adults and percentage of older adults living alone, small family size, and divorce rates (relative to marriage rates). We tested five key hypotheses regarding cultural change in individualism-collectivism. As predicted by previous theories, changes in socioeconomic structure, pathogen prevalence, and secularism accompanied changes in individualism averaged across all measures. The relationship with changes in individualism was less robust for urbanization. Contrary to previous theories, changes in individualism were positively (as opposed to negatively) related to the frequency of disasters. Time-lagged analyses suggested that only socioeconomic structure had a robust effect on individualism; changes in socioeconomic structure preceded changes in individualism. Implications for anthropology, psychology, and sociology are discussed. © The Author(s) 2015.

  4. Energy intensity developments in 40 major economies: Structural change or technology improvement?

    International Nuclear Information System (INIS)

    Voigt, Sebastian; De Cian, Enrica; Schymura, Michael; Verdolini, Elena

    2014-01-01

    This study analyzes energy intensity trends and drivers in 40 major economies using the WIOD database, a novel harmonized and consistent dataset of input–output table time series accompanied by environmental satellite data. We use logarithmic mean Divisia index decomposition to (1) attribute efficiency changes to either changes in technology or changes in the structure of the economy, (2) study trends in global energy intensity between 1995 and 2007, and (3) highlight sectoral and regional differences. For the country analysis we apply the traditional two factor index decomposition approach, while for the global analysis we use a three factor decomposition which includes the consideration of regional structural changes in the global economy. We first show that heterogeneity within each sector across countries is high. These general trends within sectors are dominated by large economies, first and foremost the United States. In most cases, heterogeneity is lower within each country across the different sectors. Regarding changes of energy intensity at the country level, improvements between 1995 and 2007 are largely attributable to technological change while structural change is less important in most countries. Notable exceptions are Japan, the United States, Australia, Taiwan, Mexico and Brazil where a change in the industry mix was the main driver behind the observed energy intensity reduction. At the global level we find that despite a shift of the global economy to more energy-intensive countries, aggregate energy efficiency improved mostly due to technological change

  5. Measuring structural change and energy use: Decomposition of the US economy from 1997 to 2002

    International Nuclear Information System (INIS)

    Weber, Christopher L.

    2009-01-01

    The steadily increasing focus on energy production and consumption has led to growing research attention to patterns of energy use within economies. Of particular interest has been comparing the driving forces of increasing efficiency and economic structural change. Input-output analysis (IOA) and decomposition analysis have become critical tools for performing such analyses. This study analyzes aggregate energy use in the United States in 1997 and 2002 to discover the causes of changing energy usage and flows. Results show that rising population and household consumption acted to drive up energy demand, but this driving force was offset by considerable structural change within the economy, particularly related to a quickly increasing trade deficit in manufacturing goods. Thus, while total energy intensity, the ratio of energy use to economic output, declined by approximately 12% between 1997 and 2002, changes in the structure of the economy explain this drop more than increased energy efficiency. The level of aggregation at which decomposition analyses are run was identified as a crucially sensitive parameter for the determination of structural change, and future studies should specifically address the amount of detail necessary to adequately measure changes in economic structure

  6. Distributed Piezoelectric Sensor System for Damage Identification in Structures Subjected to Temperature Changes.

    Science.gov (United States)

    Vitola, Jaime; Pozo, Francesc; Tibaduiza, Diego A; Anaya, Maribel

    2017-05-31

    Structural health monitoring (SHM) is a very important area in a wide spectrum of fields and engineering applications. With an SHM system, it is possible to reduce the number of non-necessary inspection tasks, the associated risk and the maintenance cost in a wide range of structures during their lifetime. One of the problems in the detection and classification of damage are the constant changes in the operational and environmental conditions. Small changes of these conditions can be considered by the SHM system as damage even though the structure is healthy. Several applications for monitoring of structures have been developed and reported in the literature, and some of them include temperature compensation techniques. In real applications, however, digital processing technologies have proven their value by: (i) offering a very interesting way to acquire information from the structures under test; (ii) applying methodologies to provide a robust analysis; and (iii) performing a damage identification with a practical useful accuracy. This work shows the implementation of an SHM system based on the use of piezoelectric (PZT) sensors for inspecting a structure subjected to temperature changes. The methodology includes the use of multivariate analysis, sensor data fusion and machine learning approaches. The methodology is tested and evaluated with aluminum and composite structures that are subjected to temperature variations. Results show that damage can be detected and classified in all of the cases in spite of the temperature changes.

  7. Distributed Piezoelectric Sensor System for Damage Identification in Structures Subjected to Temperature Changes

    Directory of Open Access Journals (Sweden)

    Jaime Vitola

    2017-05-01

    Full Text Available Structural health monitoring (SHM is a very important area in a wide spectrum of fields and engineering applications. With an SHM system, it is possible to reduce the number of non-necessary inspection tasks, the associated risk and the maintenance cost in a wide range of structures during their lifetime. One of the problems in the detection and classification of damage are the constant changes in the operational and environmental conditions. Small changes of these conditions can be considered by the SHM system as damage even though the structure is healthy. Several applications for monitoring of structures have been developed and reported in the literature, and some of them include temperature compensation techniques. In real applications, however, digital processing technologies have proven their value by: (i offering a very interesting way to acquire information from the structures under test; (ii applying methodologies to provide a robust analysis; and (iii performing a damage identification with a practical useful accuracy. This work shows the implementation of an SHM system based on the use of piezoelectric (PZT sensors for inspecting a structure subjected to temperature changes. The methodology includes the use of multivariate analysis, sensor data fusion and machine learning approaches. The methodology is tested and evaluated with aluminum and composite structures that are subjected to temperature variations. Results show that damage can be detected and classified in all of the cases in spite of the temperature changes.

  8. The impact of considering land intensification and updated data on biofuels land use change and emissions estimates.

    Science.gov (United States)

    2017-01-01

    Background: The GTAP model has been used to estimate biofuel policy induced land use changes and consequent GHG emissions for more than a decade. This paper reviews the history of the model and database modifications and improvements that have occurr...

  9. Changes in family structure in early childhood in the Millennium Cohort Study.

    Science.gov (United States)

    Panico, Lidia; Bartley, Mel; Kelly, Yvonne; McMunn, Anne; Sacker, Amanda

    2010-01-01

    This article develops a typology of family change over the first five years of children's lives using data from the Millennium Cohort Study. It examines the changes over time of parental living arrangements and describes a range of social, economic and well-being indicators. It shows that nearly three quarters of this sample of young children have not experienced changes in family structures. The most advantaged group appears to be children living with continuously married parents, followed by those who live with cohabiting parents who marry. Children who experienced changes in family structure are a diverse group. Coupled parents who separate suffer the largest drop in income over five years. Lone parents who partner gain the most income. However, their incomes are still much lower than continuously partnered parents. This article suggests that using static or overly simplified measures of family structure hides important variations in the experiences of children.

  10. The influence of structural changes to the tourist industry in Montenegro

    Directory of Open Access Journals (Sweden)

    Adžić Slavica

    2017-01-01

    Full Text Available The influence of transition on the society has reflected on the entire social-economic circumstances in Montenegro. This complex and long process has changed the stability of economic growth and the development of the national economy and has effectuated the structural changes in the economy of Montenegro. Beside transition, the war in the surroundings, international isolation and numerous other problems, which have changed flows of the social and economic development, have affected the condition of the economy system. On the example of other surrounding countries, Montenegro has persevered to provide, through the process of structural reforms, more rational and efficient company market business dealings. This paper investigates to which extent and in which manner the structural changes have reflected onto the tourist industry and which results have been achieved on the basis of reforms which should provide for the joining with the flows of European and World development. By changing the company's state-legal status, the state has strived to provide a greater level of economical activity, productivity growth, degree of participation in the social product, national revenue and employment. According to national economy aggregate indicators, the structural changes have not yet provided the balance of the entire economy to a sufficient extent. Social, economic and political stability are the assumptions for tourism development which is very sensitive to numerous changes in economy and in the society.

  11. Burning fire-prone Mediterranean shrublands: immediate changes in soil microbial community structure and ecosystem functions.

    Science.gov (United States)

    Goberna, M; García, C; Insam, H; Hernández, M T; Verdú, M

    2012-07-01

    Wildfires subject soil microbes to extreme temperatures and modify their physical and chemical habitat. This might immediately alter their community structure and ecosystem functions. We burned a fire-prone shrubland under controlled conditions to investigate (1) the fire-induced changes in the community structure of soil archaea, bacteria and fungi by analysing 16S or 18S rRNA gene amplicons separated through denaturing gradient gel electrophoresis; (2) the physical and chemical variables determining the immediate shifts in the microbial community structure; and (3) the microbial drivers of the change in ecosystem functions related to biogeochemical cycling. Prokaryotes and eukaryotes were structured by the local environment in pre-fire soils. Fire caused a significant shift in the microbial community structure, biomass C, respiration and soil hydrolases. One-day changes in bacterial and fungal community structure correlated to the rise in total organic C and NO(3)(-)-N caused by the combustion of plant residues. In the following week, bacterial communities shifted further forced by desiccation and increasing concentrations of macronutrients. Shifts in archaeal community structure were unrelated to any of the 18 environmental variables measured. Fire-induced changes in the community structure of bacteria, rather than archaea or fungi, were correlated to the enhanced microbial biomass, CO(2) production and hydrolysis of C and P organics. This is the first report on the combined effects of fire on the three biological domains in soils. We concluded that immediately after fire the biogeochemical cycling in Mediterranean shrublands becomes less conservative through the increased microbial biomass, activity and changes in the bacterial community structure.

  12. Temporal change in biological community structure in the Fountain Creek basin, Colorado, 2001-2008

    Science.gov (United States)

    Zuellig, Robert E.; Bruce, James F.; Stogner, Sr., Robert W.

    2010-01-01

    In 2001, the U.S. Geological Survey, in cooperation with Colorado Springs City Engineering, began a study to better understand the relations between environmental characteristics and biological communities in the Fountain Creek basin in order to aide water-resource management and guide future monitoring activities. To accomplish this task, environmental (streamflow, habitat, and water chemistry) and biological (fish and macroinvertebrate) data were collected annually at 24 sites over a 6- or 8-year period (fish, 2003 to 2008; macroinvertebrates, 2001 to 2008). For this report, these data were first analyzed to determine the presence of temporal change in macroinvertebrate and fish community structure among years using nonparametric multivariate statistics. Where temporal change in the biological communities was found, these data were further analyzed using additional nonparametric multivariate techniques to determine which subset of selected streamflow, habitat, or water-chemistry variables best described site-specific changes in community structure relative to a gradient of urbanization. This study identified significant directional patterns of temporal change in macroinvertebrate and fish community structure at 15 of 24 sites in the Fountain Creek basin. At four of these sites, changes in environmental variables were significantly correlated with the concurrent temporal change identified in macroinvertebrate and fish community structure (Monument Creek above Woodmen Road at Colorado Springs, Colo.; Monument Creek at Bijou Street at Colorado Springs, Colo.; Bear Creek near Colorado Springs, Colo.; Fountain Creek at Security, Colo.). Combinations of environmental variables describing directional temporal change in the biota appeared to be site specific as no single variable dominated the results; however, substrate composition variables (percent substrate composition composed of sand, gravel, or cobble) collectively were present in 80 percent of the environmental

  13. Structural and morphological changes in supramolecular-structured polymer electrolyte membrane fuel cell on addition of phosphoric acid

    Science.gov (United States)

    Hendrana, S.; Pryliana, R. F.; Natanael, C. L.; Rahayu, I.

    2018-03-01

    Phosphoric acid is one agents used in membrane fuel cell to modify ionic conductivity. Therefore, its distribution in membrane is a key parameter to gain expected conductivity. Efforts have been made to distribute phosphoric acid in a supramolecular-structured membrane prepared with a matrix. To achieve even distribution across bulk of the membrane, the inclusion of the polyacid is carried out under pressurized chamber. Image of scanning electron microscopy (SEM) shows better phosphoric acid distribution for one prepared in pressurized state. It also leads in better performing in ionic conductivity. Moreover, data from differential scanning calorimetry (DSC) indicate that the addition of phosphoric acid is prominent in the change of membrane structure, while morphological changes are captured in SEM images.

  14. Structural Changes in the Economy of the Russian Northwest: Spatial Dimension

    Directory of Open Access Journals (Sweden)

    Kolesnikov Nikolai

    2016-06-01

    Full Text Available This paper identifies and explains the trends in the economic transformations in the Russian Northwest (NWFD. It studies the changes in the structure of the gross regional product (GRP and economic specialization of the NWFD regions. The authors suggest approaches to managing structural changes in the economies of the NWFD regions. The authors propose a new method for the identification of the regional economic specialization on the basis of the reginal economy sectoral development rate. The article describes a methodology for identifying the development of the regional economic sectors using the ‘gross value added index’ calculated per capita and per sector against the national average. The article presents the analysis of the structural changes in the NWFD gross regional product. The proposed gross value added index helps to identify the upward and downward trends in each sector compared to the national average. Based on this analysis, the authors describe the nature of changes in the NWFD sectoral specialisation, which correlated with the distance to large economic centres — Moscow and St. Petersburg. The authors prove that the economic development of the Northwest macroregion follows the ‘core-periphery’ pattern. The regional economy structure depends on the position of a given region in relation to the core. Concrete approaches to managing structural changes in the economies of periphery regions are proposed.

  15. Somatic Hypermutation-Induced Changes in the Structure and Dynamics of HIV-1 Broadly Neutralizing Antibodies.

    Science.gov (United States)

    Davenport, Thaddeus M; Gorman, Jason; Joyce, M Gordon; Zhou, Tongqing; Soto, Cinque; Guttman, Miklos; Moquin, Stephanie; Yang, Yongping; Zhang, Baoshan; Doria-Rose, Nicole A; Hu, Shiu-Lok; Mascola, John R; Kwong, Peter D; Lee, Kelly K

    2016-08-02

    Antibody somatic hypermutation (SHM) and affinity maturation enhance antigen recognition by modifying antibody paratope structure to improve its complementarity with the target epitope. SHM-induced changes in paratope dynamics may also contribute to antibody maturation, but direct evidence of this is limited. Here, we examine two classes of HIV-1 broadly neutralizing antibodies (bNAbs) for SHM-induced changes in structure and dynamics, and delineate the effects of these changes on interactions with the HIV-1 envelope glycoprotein (Env). In combination with new and existing structures of unmutated and affinity matured antibody Fab fragments, we used hydrogen/deuterium exchange with mass spectrometry to directly measure Fab structural dynamics. Changes in antibody structure and dynamics were positioned to improve complementarity with Env, with changes in dynamics primarily observed at the paratope peripheries. We conclude that SHM optimizes paratope complementarity to conserved HIV-1 epitopes and restricts the mobility of paratope-peripheral residues to minimize clashes with variable features on HIV-1 Env. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Morphological and structural changes at the Merapi lava dome monitored using Unmanned Aerial Vehicles (UAVs)

    Science.gov (United States)

    Darmawan, H.; Walter, T. R.; Brotopuspito, K. S.; Subandriyo, S.; Nandaka, M. A.

    2017-12-01

    Six gas-driven explosions between 2012 and 2014 had changed the morphology and structures of the Merapi lava dome. The explosions mostly occurred during rainfall season and caused NW-SE elongated open fissures that dissected the lava dome. In this study, we conducted UAVs photogrammetry before and after the explosions to investigate the morphological and structural changes and to assess the quality of the UAV photogrammetry. The first UAV photogrammetry was conducted on 26 April 2012. After the explosions, we conducted Terrestrial Laser Scanning (TLS) survey on 18 September 2014 and repeated UAV photogrammetry on 6 October 2015. We applied Structure from Motion (SfM) algorithm to reconstruct 3D SfM point clouds and photomosaics of the 2012 and 2015 UAVs images. Topography changes has been analyzed by calculating height difference between the 2012 and 2015 SfM point clouds, while structural changes has been investigated by visual comparison between the 2012 and 2015 photo mosaics. Moreover, a quality assessment of the results of UAV photogrammetry has been done by comparing the 3D SfM point clouds to TLS dataset. Result shows that the 2012 and 2015 SfM point clouds have 0.19 and 0.57 m difference compared to the TLS point cloud. Furthermore, topography, and structural changes reveal that the 2012-14 explosions were controlled by pre-existing structures. The volume of the 2012-14 explosions is 26.400 ± 1320 m3 DRE. In addition, we find a structurally delineated unstable block at the southern front of the dome which potentially collapses in the future. We concluded that the 2012-14 explosions occurred due to interaction between magma intrusion and rain water and were facilitated by pre-existing structures. The unstable block potentially leads to a rock avalanche hazard. Furthermore, our drone photogrammetry results show very promising and therefore we recommend to use drone for topography mapping in lava dome building volcanoes.

  17. Structure changes in UO2(hfa)2 NH3 near the melting point

    International Nuclear Information System (INIS)

    Johnson, D.A.; Taylor, J.C.; Waugh, A.B.

    1982-01-01

    A reversible colour change from lemon-yellow to orange was observed for polycrystalline UO 2 (hfa) 2 NH 3 at 100 0 C (hfa = (1,1,1,5,5,5-hexafluoro-2,4-pentanedione)). The changes in the X-ray powder pattern between -196 0 and 130 0 C were followed with a Guinier-Simon focussing camera. The colour change was not due to an α - β type structural transition as found earlier in α and β-UO 2 (hfa) 2 tmp (tmp = trimethyl phosphate), but was considered to be due to changes in the hydrogen bonding of the ammonia molecules. (author)

  18. The effects of musical practice on structural plasticity: the dynamics of grey matter changes.

    Science.gov (United States)

    Groussard, Mathilde; Viader, Fausto; Landeau, Brigitte; Desgranges, Béatrice; Eustache, Francis; Platel, Hervé

    2014-10-01

    Intensive training and the acquisition of expertise are known to bring about structural changes in the brain. Musical training is a particularly interesting model. Previous studies have reported structural brain modifications in the auditory, motor and visuospatial areas of musicians compared with nonmusicians. The main goal of the present study was to go one step further, by exploring the dynamic of those structural brain changes related to musical experience. To this end, we conducted a regression study on 44 nonmusicians and amateur musicians with 0-26years of musical practice of a variety instruments. We sought first to highlight brain areas that increased with the duration of practice and secondly distinguish (thanks to an ANOVA analysis) brain areas that undergo grey matter changes after only limited years of musical practice from those that require longer practice before they exhibit changes. Results revealed that musical training results a greater grey matter volumes in different brain areas for musicians. Changes appear gradually in the left hippocampus and right middle and superior frontal regions, but later also include the right insula and supplementary motor area and left superior temporal, and posterior cingulate areas. Given that all participants had the same age and that we controlled for age and education level, these results cannot be ascribed to normal brain maturation. Instead, they support the notion that musical training could induce dynamic structural changes. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. A user-friendly web portal for analyzing conformational changes in structures of Mycobacterium tuberculosis.

    Science.gov (United States)

    Hassan, Sameer; Thangam, Manonanthini; Vasudevan, Praveen; Kumar, G Ramesh; Unni, Rahul; Devi, P K Gayathri; Hanna, Luke Elizabeth

    2015-10-01

    Initiation of the Tuberculosis Structural Consortium has resulted in the expansion of the Mycobacterium tuberculosis (MTB) protein structural database. Currently, 969 experimentally solved structures are available for 354 MTB proteins. This includes multiple crystal structures for a given protein under different functional conditions, such as the presence of different ligands or mutations. In depth analysis of the multiple structures reveal that subtle differences exist in conformations of a given protein under varied conditions. Therefore, it is immensely important to understand the conformational differences between the multiple structures of a given protein in order to select the most suitable structure for molecular docking and structure-based drug designing. Here, we introduce a web portal ( http://bmi.icmr.org.in/mtbsd/torsion.php ) that we developed to provide comparative data on the ensemble of available structures of MTB proteins, such as Cα root means square deviation (RMSD), sequence identity, presence of mutations and torsion angles. Additionally, torsion angles were used to perform principal component analysis (PCA) to identify the conformational differences between the structures. Additionally, we present a few case studies to demonstrate this database. Graphical Abstract Conformational changes seen in the structures of the enoyl-ACP reductase protein encoded by the Mycobacterial gene inhA.

  20. Impacts of Seed Dispersal on Future Vegetation Structure under Changing Climates

    Science.gov (United States)

    Lee, E.; Schlosser, C. A.; Gao, X.; Prinn, R. G.

    2011-12-01

    As the impacts between land cover change, future climates and ecosystems are expected to be substantial, there are growing needs for improving the capability of simulating the global vegetation structure and landscape as realistically as possible. Current DGVMs assume ubiquitous availability of seeds and do not consider any seed dispersal mechanisms in plant migration process, which may influence the assessment of impacts to the ecosystem that rely on the vegetation structure changes (i.e., change in albedo, runoff, and terrestrial carbon sequestration capacity). This study incorporates time-varying wind-driven seed dispersal (i.e., the SEED configuration) as a dynamic constraint to the migration process of natural vegetation in the Community Land Model (CLM)-DGVM. The SEED configuration is validated using a satellite-derived tree cover dataset. Then the configuration is applied to project future vegetation structures and their implications for carbon fluxes, albedo, and hydrology under two climate mitigation scenarios (No-policy vs. 450ppm CO2 stabilization) for the 21st century. Our results show that regional changes of vegetation structure under changing climates are expected to be significant. For example, Alaska and Siberia are expected to experience substantial shifts of forestry structure, characterized by expansion of needle-leaf boreal forest and shrinkage of C3 grass Arctic. A suggested vulnerability assessment shows that vegetation structures in Alaska, Greenland, Central America, southern South America, East Africa and East Asia are susceptible to changing climates, regardless of the two climate mitigation scenarios. Regions such as Greenland, Tibet, South Asia and Northern Australia, however, may substantially alleviate their risks of rapid change in vegetation structure, given a robust greenhouse gas stabilization target. Proliferation of boreal forests in the high latitudes is expected to amplify the warming trend (i.e., a positive feedback to

  1. Gut microbiome populations are associated with structure-specific changes in white matter architecture.

    Science.gov (United States)

    Ong, Irene M; Gonzalez, Jose G; McIlwain, Sean J; Sawin, Emily A; Schoen, Andrew J; Adluru, Nagesh; Alexander, Andrew L; Yu, John-Paul J

    2018-01-10

    Altered gut microbiome populations are associated with a broad range of neurodevelopmental disorders including autism spectrum disorder and mood disorders. In animal models, modulation of gut microbiome populations via dietary manipulation influences brain function and behavior and has been shown to ameliorate behavioral symptoms. With striking differences in microbiome-driven behavior, we explored whether these behavioral changes are also accompanied by corresponding changes in neural tissue microstructure. Utilizing diffusion tensor imaging, we identified global changes in white matter structural integrity occurring in a diet-dependent manner. Analysis of 16S ribosomal RNA sequencing of gut bacteria also showed changes in bacterial populations as a function of diet. Changes in brain structure were found to be associated with diet-dependent changes in gut microbiome populations using a machine learning classifier for quantitative assessment of the strength of microbiome-brain region associations. These associations allow us to further test our understanding of the gut-brain-microbiota axis by revealing possible links between altered and dysbiotic gut microbiome populations and changes in brain structure, highlighting the potential impact of diet and metagenomic effects in neuroimaging.

  2. Molecular dynamics simulation of structural changes during the collision of copper nanoparticles

    International Nuclear Information System (INIS)

    Rojas T, Justo; Instituto Peruano de Energia Nuclear, Lima; Copa, Betty

    2009-01-01

    Molecular dynamics simulations with embedded-atom potential (EAM) have been performed to study the energetic and structural changes during the collision and coalescence of two Cu n nanoparticles. We simulated collision of nanoparticles at several temperatures below the melting point and with different impact energy. Analyzing the potential energy change during the collision we identify three clearly defined stages. The pair correlation function and the pair analysis technique are used to reveal the structural changes in the collision process. The variation in the time of the population of different pairs has been quantified, being observed diverse structural transformations. During the collision of two equal icosahedral nanoparticles ( Cu 55 ) has been observed different behavior of 1551 pairs depending on the impact velocity. (author).

  3. In situ monitoring of structural changes during colloidal self-assembly.

    Science.gov (United States)

    Koh, Yaw Koon; Wong, Chee Cheong

    2006-01-31

    Reflectance spectroscopy is utilized to monitor structural changes during the self-assembly of a monodisperse colloidal system at the meniscus of a sessile drop on an inert substrate. Treating the ordered colloidal structure as a photonic crystal is equivalent to monitoring the changes in the photonic band gap (PBG) as the colloidal system self-assembles heterogeneously into a crystal through solvent evaporation in ambient conditions. Using a modified Bragg's law model of the photonic crystal, we can trace the structural evolution of the self-assembling colloidal system. After a certain induction period, a face-centered cubic (FCC) structure emerges, albeit with a lattice parameter larger than that of a true close-packed structure. This FCC structure is maintained while the lattice parameter shrinks continuously with further increase in the colloidal concentration due to drying. When the structure reaches a lattice parameter 1.09 times the size of that of a true close-packed structure, it undergoes an abrupt decrease in lattice spacing, apparently similar to those reported for lattice-distortive martensitic transformations. This abrupt final lattice shrinkage agrees well with the estimated Debye screening length of the electric double layer of charged colloids and could be the fundamental reason behind the cracking commonly seen in colloidal crystals.

  4. New approach to increase the gas throughput through mica track microfilters by changing their pore structure

    International Nuclear Information System (INIS)

    Shi-lun Guo; Tress, G.; Vater, P.; Khan, E.U.; Dersch, R.; Plachky, M.; Brandt, R.; Khan, H.A.

    1986-01-01

    A new approach has been developed to increase the gas throughput of nuclear track microfilters by changing the structure of the etched channels. This can be achieved by reducing the pore length of the filters and by changing the etched channel to two open funnels with a short neck in-between. The mica track microfilters are etched with hot concentrated NaOH solution only. The bulk etch rate is found to be 100 A h -1 . The structure of the mica pores has been studied in detail with optical and scanning electron microscopes. We find that the etching behavior of mica is anisotropic in several directions. A ''funnel-neck-funnel'' structure has been formed in mica by etching in NaOH. The gas throughput increase has been calculated from the modified structure of the mica pore. (author)

  5. Elevated Air Humidity Changes Soil Bacterial Community Structure in the Silver Birch Stand.

    Science.gov (United States)

    Truu, Marika; Ostonen, Ivika; Preem, Jens-Konrad; Lõhmus, Krista; Nõlvak, Hiie; Ligi, Teele; Rosenvald, Katrin; Parts, Kaarin; Kupper, Priit; Truu, Jaak

    2017-01-01

    Soil microbes play a fundamental role in forest ecosystems and respond rapidly to changes in the environment. Simultaneously with the temperature increase the climate change scenarios also predict an intensified hydrological cycle for the Baltic Sea runoff region. The aim of this study was to assess the effect of elevated air humidity on the top soil microbial community structure of a silver birch ( Betula pendula Roth.) stand by using a free air humidity manipulation facility (FAHM). The bacterial community structures of bulk soil and birch rhizosphere were analyzed using high-throughput sequencing of bacteria-specific16S rRNA gene fragments and quantification of denitrification related genes. The increased air humidity altered both bulk soil and rhizosphere bacterial community structures, and changes in the bacterial communities initiated by elevated air humidity were related to modified soil abiotic and biotic variables. Network analysis revealed that variation in soil bacterial community structural units is explained by altered abiotic conditions such as increased pH value in bulk soil, while in rhizosphere the change in absorptive root morphology had a higher effect. Among root morphological traits, the absorptive root diameter was strongest related to the bacterial community structure. The changes in bacterial community structures under elevated air humidity are associated with shifts in C, N, and P turnover as well as mineral weathering processes in soil. Increased air humidity decreased the nir and nosZ gene abundance in the rhizosphere bacterial community. The potential contribution of the denitrification to the N 2 O emission was not affected by the elevated air humidity in birch stand soil. In addition, the study revealed a strong link between the bacterial community structure, abundance of denitrification related genes, and birch absorptive root morphology in the ecosystem system adaptation to elevated air humidity.

  6. Spatial structure of the meroplankton community along a Patagonian fjord - The role of changing freshwater inputs

    Science.gov (United States)

    Meerhoff, Erika; Tapia, Fabián J.; Castro, Leonardo R.

    2014-12-01

    Freshwater inputs are major drivers of circulation, hydrographic structure, and productivity patterns along estuarine systems. We assessed the degree to which meroplankton community structure in the Baker/Martinez fjord complex (Chilean Patagonia, 47.5°S) responds to spatial and temporal changes in hydrographic conditions driven by seasonal changes in Baker river outflow. Zooplankton and hydrographic measurements were conducted along the fjord in early spring (October) and late summer (February), when river outflow was minimal and maximal, respectively. Major meroplankton groups found on these surveys were larval barnacles, crabs, bivalves and gastropods. There was a clear change in community structure between October and February, explained by a switch in the numerically dominant group from barnacle to bivalve larvae. This change in community structure was related to changes in hydrographic structure along the fjord, which are mainly associated with seasonal changes in the Baker river outflow. A variance partition analysis showed no significant spatial trend that could account for the variation in meroplankton along the Martinez channel, whereas temporal variability and environmental variables accounted for 36.6% and 27.6% of the variance, respectively. When comparing meroplankton among the Baker and Martinez channels in October, changes in environmental variables explained 44.9% of total variance, whereas spatial variability accounted for 23.5%. Early and late-stage barnacle larvae (i.e. nauplii and cyprids) were more abundant in water with lower temperature, and higher dissolved oxygen and chlorophyll-a concentration, whereas bivalve larvae were more strongly associated to warmer waters. The seasonal shift in numerical dominance, from barnacle larvae in early spring to bivalve larvae in late summer, suggests that reproduction of these groups is triggered by substantially different sets of conditions, both in terms of hydrography and food availability. The

  7. REVEALING STUDENTS' COGNITIVE STRUCTURE ABOUT PHYSICAL AND CHEMICAL CHANGE: USE OF A WORD ASSOCIATION TEST

    OpenAIRE

    Hasene Esra Yildirir; Hatice Demirkol

    2018-01-01

    The current study aimed at examining the utility of a word association test in revealing students’ cognitive structure in a specific chemistry topic through a word association test. The participants were 153 6th graders in a western Turkish city. The results revealed that the word association test serves a useful purpose in exploring the students’ cognitive structure with regard to physical and chemical change and identifying their misconceptions about this topic. Some students gave irrelevan...

  8. In-situ investigations of structural changes during cyclic loading by high resolution reciprocal space mapping

    DEFF Research Database (Denmark)

    Diederichs, Annika M.; Thiel, Felix; Lienert, Ulrich

    2017-01-01

    Abstract A major failure reason for structural materials is fatigue-related damage due to repeatedly changing mechanical loads. During cyclic loading dislocations self-organize into characteristic ordered structures, which play a decisive role for the materials lifetime. These heterogeneous...... the materials behavior during cyclic deformation and to improve the material design. While monitoring macroscopic stress and strain during cyclic loading, reciprocal space maps of diffraction peaks from single grains are obtained with high resolution. High Resolution Reciprocal Space Mapping was applied...

  9. Structural, biochemical, cellular, and functional changes in skeletal muscle extracellular matrix with aging

    DEFF Research Database (Denmark)

    Kragstrup, T W; Kjaer, M; Mackey, A L

    2011-01-01

    in skeletal muscle ECM contribute to the increased stiffness and impairment in force generated by the contracting muscle fibers seen with aging. The cellular interactions provide and potentially coordinate an adaptation to mechanical loading and ensure successful regeneration after muscle injury. Some......The extracellular matrix (ECM) of skeletal muscle is critical for force transmission and for the passive elastic response of skeletal muscle. Structural, biochemical, cellular, and functional changes in skeletal muscle ECM contribute to the deterioration in muscle mechanical properties with aging......-links and a buildup of advanced glycation end-product cross-links. Altered mechanotransduction, poorer activation of satellite cells, poorer chemotactic and delayed inflammatory responses, and a change in modulators of the ECM are important cellular changes. It is possible that the structural and biochemical changes...

  10. Structural, biochemical, cellular, and functional changes in skeletal muscle extracellular matrix with aging

    DEFF Research Database (Denmark)

    Kragstrup, T W; Kjaer, M; Mackey, A L

    2011-01-01

    The extracellular matrix (ECM) of skeletal muscle is critical for force transmission and for the passive elastic response of skeletal muscle. Structural, biochemical, cellular, and functional changes in skeletal muscle ECM contribute to the deterioration in muscle mechanical properties with aging......-links and a buildup of advanced glycation end-product cross-links. Altered mechanotransduction, poorer activation of satellite cells, poorer chemotactic and delayed inflammatory responses, and a change in modulators of the ECM are important cellular changes. It is possible that the structural and biochemical changes...... in skeletal muscle ECM contribute to the increased stiffness and impairment in force generated by the contracting muscle fibers seen with aging. The cellular interactions provide and potentially coordinate an adaptation to mechanical loading and ensure successful regeneration after muscle injury. Some...

  11. Structural, biochemical, cellular, and functional changes in skeletal muscle extracellular matrix with aging

    DEFF Research Database (Denmark)

    Kragstrup, Tue Wenzel; Kjaer, M; Mackey, A L

    2011-01-01

    -links and a buildup of advanced glycation end-product cross-links. Altered mechanotransduction, poorer activation of satellite cells, poorer chemotactic and delayed inflammatory responses, and a change in modulators of the ECM are important cellular changes. It is possible that the structural and biochemical changes......The extracellular matrix (ECM) of skeletal muscle is critical for force transmission and for the passive elastic response of skeletal muscle. Structural, biochemical, cellular, and functional changes in skeletal muscle ECM contribute to the deterioration in muscle mechanical properties with aging...... in skeletal muscle ECM contribute to the increased stiffness and impairment in force generated by the contracting muscle fibers seen with aging. The cellular interactions provide and potentially coordinate an adaptation to mechanical loading and ensure successful regeneration after muscle injury. Some...

  12. Changes in anterior ocular structures and macula following deep sclerectomy with collagen implant.

    Science.gov (United States)

    Suominen, Sakari M A; Harju, Mika P; Hautamäki, Asta M E; Vesti, Eija T

    2018-01-01

    To determine the effect of intraocular pressure (IOP) lowering with deep sclerectomy (DS) on visual acuity, macular structures, and anterior ocular dimensions during the early postoperative period. We prospectively analyzed 35 eyes of 35 patients scheduled for DS. Our focus with the measurements was on early postoperative changes in anterior ocular and macular structures related to IOP lowering during the first month after DS. In addition to a clinical ophthalmologic examination, our measurements included corneal topography, measurement of ocular dimensions with optical biometry, and examination of macular structure with optical coherence tomography. These measurements were repeated 1, 2, and 4 weeks postoperatively. Best-corrected visual acuity (BCVA) decreased 1 week postoperatively to 0.22 (0.20) LogMAR (p = 0.006). The BCVA then increased to its preoperative level, 0.17 (0.18) (p = 0.28), after 4 weeks. Axial length decreased from 24.12 (1.81) mm to 24.04 (1.81) (p<0.001) 4 weeks postoperatively. The steeper meridian of corneal curvature and average corneal power increased postoperatively; central corneal thickness was decreased. No significant change appeared in other measurements. We found changes in corneal curvature and ocular dimensions after DS. These changes were relatively small and do not completely explain the decrease in visual acuity postoperatively. Macular structures showed no changes.

  13. Brain Events Underlying Episodic Memory Changes in Aging: A Longitudinal Investigation of Structural and Functional Connectivity.

    Science.gov (United States)

    Fjell, Anders M; Sneve, Markus H; Storsve, Andreas B; Grydeland, Håkon; Yendiki, Anastasia; Walhovd, Kristine B

    2016-03-01

    Episodic memories are established and maintained by close interplay between hippocampus and other cortical regions, but degradation of a fronto-striatal network has been suggested to be a driving force of memory decline in aging. We wanted to directly address how changes in hippocampal-cortical versus striatal-cortical networks over time impact episodic memory with age. We followed 119 healthy participants (20-83 years) for 3.5 years with repeated tests of episodic verbal memory and magnetic resonance imaging for quantification of functional and structural connectivity and regional brain atrophy. While hippocampal-cortical functional connectivity predicted memory change in young, changes in cortico-striatal functional connectivity were related to change in recall in older adults. Within each age group, effects of functional and structural connectivity were anatomically closely aligned. Interestingly, the relationship between functional connectivity and memory was strongest in the age ranges where the rate of reduction of the relevant brain structure was lowest, implying selective impacts of the different brain events on memory. Together, these findings suggest a partly sequential and partly simultaneous model of brain events underlying cognitive changes in aging, where different functional and structural events are more or less important in various time windows, dismissing a simple uni-factorial view on neurocognitive aging. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  14. Parallel structures for disaster risk reduction and climate change adaptation in Southern Africa

    Directory of Open Access Journals (Sweden)

    Per Becker

    2013-01-01

    Full Text Available During the last decade, the interest of the international community in the concepts of disaster risk reduction and climate change adaptation has been growing immensely. Even though an increasing number of scholars seem to view these concepts as two sides of the same coin (at least when not considering the potentially positive effects of climate change, in practice the two concepts have developed in parallel rather than in an integrated manner when it comes to policy, rhetoric and funding opportunities amongst international organisations and donors. This study investigates the extent of the creation of parallel structures for disaster risk reduction and climate change adaptation in the Southern African Development Community (SADC region. The chosen methodology for the study is a comparative case study and the data are collected through focus groups and content analysis of documentary sources, as well as interviews with key informants. The results indicate that parallel structures for disaster risk reduction and climate change adaptation have been established in all but one of the studied countries. The qualitative interviews performed in some of the countries indicate that stakeholders in disaster risk reduction view this duplication of structures as unfortunate, inefficient and a fertile setup for conflict over resources for the implementation of similar activities. Additional research is called for in order to study the concrete effects of having these parallel structures as a foundation for advocacy for more efficient future disaster risk reduction and climate change adaptation.

  15. Elevated Air Humidity Changes Soil Bacterial Community Structure in the Silver Birch Stand

    OpenAIRE

    Truu, Marika; Ostonen, Ivika; Preem, Jens-Konrad; L?hmus, Krista; N?lvak, Hiie; Ligi, Teele; Rosenvald, Katrin; Parts, Kaarin; Kupper, Priit; Truu, Jaak

    2017-01-01

    Soil microbes play a fundamental role in forest ecosystems and respond rapidly to changes in the environment. Simultaneously with the temperature increase the climate change scenarios also predict an intensified hydrological cycle for the Baltic Sea runoff region. The aim of this study was to assess the effect of elevated air humidity on the top soil microbial community structure of a silver birch (Betula pendula Roth.) stand by using a free air humidity manipulation facility (FAHM). The bact...

  16. U.S. Cotton Prices and the World Cotton Market: Forecasting and Structural Change

    OpenAIRE

    Isengildina-Massa, Olga; MacDonald, Stephen

    2009-01-01

    The purpose of this study was to analyze structural changes that took place in the cotton industry in recent years and develop a statistical model that reflects the current drivers of U.S. cotton prices. Legislative changes authorized the U.S. Department of Agriculture to resume publishing cotton price forecasts for the first time in 79 years. In addition, systematic problems have become apparent in the forecasting models used by USDA and elsewhere, highlighting the need for an updated review...

  17. The effect of exchange-correlation on change and stability of crystal structure

    International Nuclear Information System (INIS)

    Yazdani, A.; Niazi, M.; Alimardan, V.

    2007-01-01

    Since exchange interaction energy has effect on band structure via polarization of spin of free electron, then can directly effects formation crystal structure. Therefore exchange-correlation is able to have an effect on determination of crystal structure or its change and stability. This energy is subject to fluctuation range of electrons between conduction band and valance band or density of electrons which due to increase the entropy of system, via Gibss Energy .We investigated these factors: 1) Size of ions 2) Density of States 3) Range of inter atomic and pair-potential.

  18. Structural Changes of International Trade Flows under the Impact of Globalization

    Directory of Open Access Journals (Sweden)

    Anca Dachin

    2006-08-01

    Full Text Available Structural changes of international trade flows indicate modifications in competitiveness of countries, in terms of production, technological upgrading and exports under the pressure of globalization. The paper aims to point out sources of competitive advantages especially in manufacturing exports of different groups of countries. The focus is on the shifts in the structure of manufacturing in the European Union and their effects on international rankings in export performances. An important issue refers to the opportunities given by the enlargement of the European Union and their impact on EU trade structures.

  19. Structural changes in slenderized yak hair induced by heat-humidity conditions using Raman spectroscopy

    Science.gov (United States)

    Liu, H. L.; Zhao, B. Y.; Yu, W. D.

    2013-04-01

    In this study, estimation of structure was accomplished with the use of deconvolution, secondary derivation and curve-fitting. The structural changes of slenderized yak hair treated by heat-humidity conditions were quantified by analyzing the disulfide bond (S-S), amide I and amide III regions. The results showed that the amount of the disulphide bond in the yak hair decreases with the increase of treating time. The secondary structure of yak hair transforms from the α-helix and β pleated to the disordered conformation during the heat humidity processing.

  20. Аsymmetry of Structural Institutional and Technological Changes in Economy

    Directory of Open Access Journals (Sweden)

    Katkovа Marina Andreevna

    2014-12-01

    Full Text Available The article is devoted to the research on interrelation between institutional and technological changes. The authors provide the convincing argument in favor of the thesis on asymmetry of structural, institutional and technological changes. The complex of analytic methods is used in the work – comparative statics, static analysis, dynamic analysis. The analysis results in the conclusion on strengthening the heterogeneity, instability and uncertainty of the social and economic phenomena and processes. The authors comprehend structural changes as the changes in ratios and proportions of economic structure. They point to the emergence of new integrated characteristics and describe the synergetic effect of the general development. The use of the theory of technological modes allowed allocating radical and local shifts. The particular emphasis is placed on the analysis of reversible and irreversible structural and technological shifts as a special form of structural and technological changes. The application of the method of institutional statics and dynamics is effective in the analysis of technological and institutional symmetry / asymmetry. The emergence of negative institutional changes is explained by insufficient, inadequate or fragmentary assimilation of market institutes. The institutes interfering the innovative development stand against the institutes of innovative development. The institutional traps of structural and technological transformations are subdivided by authors into the traps of micro- and macrolevel. The authors point to the difficulty of assessing the institutes of microlevel by means of statistical data. They suggest using the phenomena which are under the control of authorities and subject to regulation as indicators. To define the opportunities of institutional management and the borders of government intervention the authors investigate in detail the institutional traps. They include moral and psychological unreadiness

  1. The Changing Rules of the Game, Volleyball Player Systematic Structure and Effects in Applying

    Directory of Open Access Journals (Sweden)

    Özgür DİNÇER

    2015-08-01

    Full Text Available Purpose: We the purpose of this study, ranging from past to present and play volleyball rule changes that occur related to industry structure, how structure affects in applying with a systematic trial. Method: Volleyball, starting from the date of the present day sports entertainment, sport has become a subject performance. . As regards; the changing rules of the game, in terms of volleyball player systematic structure and effects on performance. The changing rules of the game, volleyball player systematic structure and effects the exhibition of the game, tactical understanding of the game is to combine the implementation of different systems to meet the needs of training and competition has created situations. Volleyball to purpose of changing the rules of the game, service, location and block combinations to improve defense, reducing the effect of conditions of service coverage and attack the ball to extend the duration of stay in the game. Thus, the visuals might volleyball, in terms of spectators and media will become attractive. While this study, scan was used during the research literature. Results: According to the data obtained from the literature, that the structural changes in the volleyball is thought to cause the positive and negative impact in the volleyball. Conclusion: Result of this research, the changing rules of the game affected the players' and the exhibition of the game and the diversity of training, volleyball game speed has increased, and became the focus of visual winning. The conclusion of every move made in the field with a number of players has increased and with it the responsibility of the importance of individual tactical exercises may have gained more importance.

  2. Climate Changes and their Influence on the Design of Hydraulic Structures from Romania

    Directory of Open Access Journals (Sweden)

    Florin Trofin

    2013-09-01

    Full Text Available During the last decades, the human being influenced environmentally the Earth, causing global environmental changes of such a size that have become global phenomena. These changes include the climate, ozone layer depletion, biogeochemical cycles, hydrological cycle, and water resources, raising the ocean levels or thermohaline circulation. The hydrological cycle and water resources changes have significant effects on the design of hydraulic structures, provided they are exploited in the presence or absence of major climatic factors, such as water, air, or soil.

  3. Tracking soil structural changes during root growth with sequential X-Ray CT scanning

    Science.gov (United States)

    Schmidt, Sonja; Bengough, Glyn; Hallett, Paul

    2014-05-01

    Crop productivity is highly dependent on a good supply of water and nutrients. With increasing demand for food and variable water regimes due to climate change, it is important to get a better understanding on the processes involved in water and nutrient uptake by roots. Changes in soil structure affect water and nutrient availabilities for plants. It is known that roots change their environment during growth but little is known on how soil structural properties change as roots penetrate soils. More detailed information on root growth induced changes in the rhizosphere will help us to model water and nutrient uptake by plants. The objective of this study was to measure directly how soil structure changes in close proximity to the root as a seedling root penetrates through the soil. 3D volumetric images of maize root growth during six hours were obtained using X-ray microtomography at a resolution of 21 μm. Roots were grown in soils of two different compaction levels (50 kPa and 200 kPa uniaxial load) and matric potentials (10 kPa and 100 kPa). Changes in porosity, pore connectivity and root-soil contact were determined from 2D cross sections for each time step. The 2D cross sections were chosen at 4 different positions in the sample, and each section was divided into sections of 64 voxels (1.3 mm2) to determine changes in porosity and connectivity with distance from the root. Soil movement caused by root growth was quantified from 2D cross sections at different positions along the sample using Particle image velocimetry (PIV). Changes in soil structure during root growth were observed. Porosity in close proximity to the root decreased whereas root-soil contact increased with time. The PIV showed a radial deformation of the soil. Greatest deformation was found close to the root. Some aggregates fractured during root growth whereas others were pushed into the pore space. These data on the changes in soil structure will help us to predict water and nutrient

  4. QUANTITATIVE AND STRUCTURAL CHANGES OF TESTIS AND SEMEN QUALITY PARAMETERS CHANGES CAUSED BY PERORAL ADMINISTRATION OF DIAZINON IN RATS

    Directory of Open Access Journals (Sweden)

    Svätoslav Hluchý

    2012-04-01

    Full Text Available The aim of this study was to find the quantitative and structural changes in the rat testis and changes of semen quality after a diazinon administration. METHODS: Rats received diazinon (99% purity in thier drinking water (40 mg.l-1 with free access. Age of rats at the beginning of the experiment was 30 days and experiment lasted for next 90 days. The histological samples were evaluated by histological and morphometric methods in light microscopy and the samples of semen were evaluated with CASA method. RESULTS: Disintergation of cellular associations in the seminiferous epithelium, germ cells evacuation into the tubule lumen and thier necrosis were mostly observed. Rarely vacuolisation and cracks of epithelium and fibrotisation of interstitial tissue were noted. Morphometric methods have shown extension of epithelium (P subcellular structures and their functions may be damaged which can lead to subfertility. Further investigation of diazinon is needed for verification of our hypothesis.doi:10.5219/188

  5. Detecting Changes in Forest Structure over Time with Bi-Temporal Terrestrial Laser Scanning Data

    Directory of Open Access Journals (Sweden)

    Timo Melkas

    2012-10-01

    Full Text Available Changes to stems caused by natural forces and timber harvesting constitute an essential input for many forestry-related applications and ecological studies, especially forestry inventories based on the use of permanent sample plots. Conventional field measurement is widely acknowledged as being time-consuming and labor-intensive. More automated and efficient alternatives or supportive methods are needed. Terrestrial laser scanning (TLS has been demonstrated to be a promising method in forestry field inventories. Nevertheless, the applicability of TLS in recording changes in the structure of forest plots has not been studied in detail. This paper presents a fully automated method for detecting changes in forest structure over time using bi-temporal TLS data. The developed method was tested on five densely populated forest plots including 137 trees and 50 harvested trees in point clouds. The present study demonstrated that 90 percent of tree stem changes could be automatically located from single-scan TLS data. These changes accounted for 92 percent of the changed basal area. The results indicate that the processing of TLS data collected at different times to detect tree stem changes can be fully automated.

  6. Structural and Institutional Changes in NATO after the End of the Cold War

    Directory of Open Access Journals (Sweden)

    O K Petrovich-Belkin

    2011-12-01

    Full Text Available The article deals with some fundamental structural and organizational changes which took place in NATO after the end of the Cold War. In particular the article touches upon some issues associated with the NATO expansion and with the origin of new authorities and cooperation programs in the North Atlantic Alliance.

  7. Changes in microbial community structure following herbicide (glyphosate) additions to forest soils

    Science.gov (United States)

    Alice W. Ratcliff; Matt D. Busse; Carol J. Shestak

    2006-01-01

    Glyphosate applied at the recommended field rate to a clay loam and a sandy loam forest soil resulted in few changes in microbial community structure. Total and culturable bacteria, fungal hyphal length, bacterial:fungal biomass, carbon utilization profiles (BIOLOG), and bacterial and fungal phospholipid fatty acids (PLFA) were unaffected 1, 3, 7, or 30 days...

  8. Responses of redwood soil microbial community structure and N transformations to climate change

    Science.gov (United States)

    Damon C. Bradbury; Mary K. Firestone

    2012-01-01

    Soil microorganisms perform critical ecosystem functions, including decomposition, nitrogen (N) mineralization and nitrification. Soil temperature and water availability can be critical determinants of the rates of these processes as well as microbial community composition and structure. This research examined how changes in climate affect bacterial and fungal...

  9. Structural changes of DNA in heavy ion-induced mutants on Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Tano, S.; Shikazono, N.; Tanaka, A.; Yokota, Y.; Watanabe, H. [Japan Atomic Research Research Inst., Watanuki, Takasaki (Japan). Advanced Science Research Center

    1997-09-01

    In order to investigate the frequency of structural changes induced by high LET radiation in plants, a comparison was made between DNA fragments amplified by the polymerase chain reaction (PCR) from C ion- and electron-induced Arabidopsis mutants at GL and TT loci. (orig./MG)

  10. Upgrade of Coastal Defence Structures Against Increased Loadings Caused by Climate Change

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Andersen, Thomas Lykke; Lara, Javier L.

    2014-01-01

    increase in long-term wind/wave conditions as predicted for the North Sea by the Danish Coastal Authority. Both conditions of non-acceptable and acceptable increase in structure crest level are considered. Moreover, a scenario for steepening of the foreshore due to morphological changes caused by increased...

  11. Structural joint changes, malalignment, and laxity in osteoarthritis of the knee

    NARCIS (Netherlands)

    van der Esch, M.; Steultjens, M.; Wieringa, H.; Dinant, H.; Dekker, J.

    2005-01-01

    To assess the relationship between (i) structural joint changes (i.e. joint space narrowing and osteophyte formation) and laxity and (ii) joint malalignment and laxity in osteoarthritis (OA) of the knee. A cross-sectional study was carried out on 35 outpatients with osteoarthritis of the knee.

  12. Age-related changes of structures in cerebellar cortex of cat

    Indian Academy of Sciences (India)

    We studied the structures of the cerebellar cortex of young adult and old cats for age-related changes, which were statistically analysed. Nissl staining was used to visualize the cortical neurons. The immunohistochemical method was used to display glial fibrillary acidic protein (GFAP)-immunoreactive (IR) astrocytes and ...

  13. Characterizing changes in soil bacterial community structure in response to short-term warming

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Jinbo [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing China; School of Marine Sciences, Ningbo University, Ningbo China; Sun, Huaibo [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing China; Peng, Fei [Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou China; Zhang, Huayong [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing China; Xue, Xian [Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou China; Gibbons, Sean M. [Argonne National Laboratory Biosciences Division, Argonne IL USA; Graduate Program in Biophysical Sciences, University of Chicago, Chicago IL USA; Gilbert, Jack A. [Argonne National Laboratory Biosciences Division, Argonne IL USA; Department of Ecology and Evolution, University of Chicago, Chicago IL USA; Chu, Haiyan [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing China

    2014-02-18

    High altitude alpine meadows are experiencing considerably greater than average increases in soil surface temperature, potentially as a result of ongoing climate change. The effects of warming on plant productivity and soil edaphic variables have been established previously, but the influence of warming on soil microbial community structure has not been well characterized. Here, the impact of 15 months of soil warming (both + 1 and + 2 degrees C) on bacterial community structure was examined in a field experiment on a Tibetan plateau alpine meadow using bar-coded pyrosequencing. Warming significantly changed (P < 0.05) the structure of the soil bacterial community, but the alpha diversity was not dramatically affected. Changes in the abundance of the Actinobacteria and Alphaproteobacteria were found to contribute the most to differences between ambient (AT) and artificially warmed conditions. A variance partitioning analysis (VPA) showed that warming directly explained 7.15% variation in bacterial community structure, while warming-induced changes in soil edaphic and plant phenotypic properties indirectly accounted for 28.3% and 20.6% of the community variance, respectively. Interestingly, certain taxa showed an inconsistent response to the two warming treatments, for example Deltaproteobacteria showed a decreased relative abundance at + 1 degrees C, but a return to AT control relative abundance at + 2 degrees C. This suggests complex microbial dynamics that could result from conditional dependencies between bacterial taxa.

  14. Structural changes of DNA in heavy ion-induced mutants on Arabidopsis

    International Nuclear Information System (INIS)

    Tano, S.; Shikazono, N.; Tanaka, A.; Yokota, Y.; Watanabe, H.

    1997-01-01

    In order to investigate the frequency of structural changes induced by high LET radiation in plants, a comparison was made between DNA fragments amplified by the polymerase chain reaction (PCR) from C ion- and electron-induced Arabidopsis mutants at GL and TT loci. (orig./MG)

  15. A Self-Ethnographic Investigation of Continuing Education Program in Engineering Arising from Economic Structural Change

    Science.gov (United States)

    Kaihlavirta, Auri; Isomöttönen, Ville; Kärkkäinen, Tommi

    2015-01-01

    This paper provides a self-ethnographic investigation of a continuing education program in engineering in Central Finland. The program was initiated as a response to local economic structural change, in order to offer re-education possibilities for a higher educated workforce currently under unemployment threat. We encountered considerable…

  16. Structuring Cooperative Learning for Motivation and Conceptual Change in the Concepts of Mixtures

    Science.gov (United States)

    Belge Can, Hatice; Boz, Yezdan

    2016-01-01

    This study investigates the effect of structuring cooperative learning based on conceptual change approach on grade 9 students' understanding the concepts of mixtures and their motivation, compared with traditional instruction. Among six classes of a high school, two of them were randomly assigned to cooperative learning group where students were…

  17. The changing industry structure of software development for consumer electronics and its consequences for software architectures

    NARCIS (Netherlands)

    Hartmann, Herman; Trew, Tim; Bosch, Jan

    During the last decade the structure of the consumer electronics industry has been changing profoundly. Current consumer electronics products are built using components from a large variety of specialized firms, whereas previously each product was developed by a single, vertically integrated

  18. Agents of Structural Change : The Role of Firms and Entrepreneurs in Regional Diversification

    NARCIS (Netherlands)

    Neffke, Frank; Hartog, Matté|info:eu-repo/dai/nl/31590769X; Boschma, Ron|info:eu-repo/dai/nl/123155541; Henning, Martin

    2018-01-01

    Who introduces structural change in regional economies: Entrepreneurs or existing firms? And do local or nonlocal establishment founders create most novelty in a region? We develop a theoretical framework that focuses on the roles different agents play in regional transformation. We then apply this

  19. Heat waves measured with MODIS land surface temperature data predict changes in avian community structure

    Science.gov (United States)

    Thomas P. Albright; Anna M. Pidgeon; Chadwick D. Rittenhouse; Murray K. Clayton; Curtis H. Flather; Patrick D. Culbert; Volker C. Radeloff

    2011-01-01

    Heat waves are expected to become more frequent and severe as climate changes, with unknown consequences for biodiversity. We sought to identify ecologically-relevant broad-scale indicators of heat waves based on MODIS land surface temperature (LST) and interpolated air temperature data and assess their associations with avian community structure. Specifically, we...

  20. The Social Consequences of Postcommunist Structural Change: An Analysis of Suicide Trends in Eastern Europe

    Science.gov (United States)

    Minagawa, Yuka

    2013-01-01

    Guided by Durkheim's classic theory of suicide, this article examines suicide trends and determinants in Eastern European countries for the period of 1989-2006, with particular attention given to the association between postcommunist social change and suicide mortality. I find that countries characterized by more drastic structural change…

  1. What Does Global Migration Network Say about Recent Changes in the World System Structure?

    Science.gov (United States)

    Zinkina, Julia; Korotayev, Andrey

    2014-01-01

    Purpose: The aim of this paper is to investigate whether the structure of the international migration system has remained stable through the recent turbulent changes in the world system. Design/methodology/approach: The methodology draws on the social network analysis framework--but with some noteworthy limitations stipulated by the specifics of…

  2. Structural changes of organic solids caused by irradiation: raman study at very low temperatures

    International Nuclear Information System (INIS)

    Hase, Hirotomo; Ishioka, Kunie; Miyatake, Yoko.

    1995-01-01

    In this paper we first describe a simple liquid helium cryostat and a device of making and mounting organic solid samples. We then present the Raman spectra for irradiated ethanol crystal that were obtained by using the new cryostat and demonstrate how the Raman method is useful for getting insight into structural changes of organic solids caused by irradiation. (J.P.N.)

  3. PRINCIPLES OF MARKET ECONOMY AND STRUCTURAL CHANGES IN THE RUSSIAN INSTRUMENT

    Directory of Open Access Journals (Sweden)

    V. N. Voronina

    2012-01-01

    Full Text Available This paper deals with result analysis of incoming of native instrument making into market economy. Reasons of dramatically worsening of many of enterprises condition and factors that are putting obstacles to its improvement are shown. Also variants of competiveness increasing ofRussian instruments are considered taking in account possible structure changes in its sphere.

  4. Extrusion of rice, bean, and corn starches: extrudate structure and molecular changes in amylose and amylopectin

    Science.gov (United States)

    This study evaluated the effects of starch source and amylose content on expansion ratio, density and texture of expanded extrudates, as well as the structural and molecular changes that occurred in starch granules as a function of extrusion. Rice starches (8%, 20% and 32% amylose), carioca bean sta...

  5. CHANGES IN EARTHWORM DENSITY AND COMMUNITY STRUCTURE DURING SECONDARY SUCCESSION IN ABANDONED TROPICAL PASTURES

    Science.gov (United States)

    Xiaoming Zou; Grizelle Gonzalez

    1997-01-01

    Plant community succession alters the quantity and chemistry of organic inputs to soils. These differences in organic input may trigger changes in soil fertility and fauna1 activity. We examined earthworm density and community structure along a successional sequence of plant communities in abandoned tropical pastures in Puerto Rico. The chronological sequence of these...

  6. Structural Change in Advanced Nations : A New Set of Stylised Facts

    NARCIS (Netherlands)

    Jorgenson, Dale W.; Timmer, Marcel P.

    2011-01-01

    We provide new evidence on patterns of structural change in advanced economies, reconsidering the stylised facts put forward by Kaldor (1963), Kuznets (1971), and Maddison (1980). Since 1980, the services sector has overwhelmingly predominated in the economic activity of the European Union, Japan,

  7. Regional impacts of technical change: the case of structural particleboard in the United States.

    Science.gov (United States)

    Zhi Xu; David N. Bengston; Hans M. Gregersen; Allen L. Lundgren

    1992-01-01

    Analyzes the regional impacts of research benefits in the United States due to the introduction of structural particleboard. The distribution of consumer benefits, producer benefits, direct employment impacts, and changes in wood requirements are analyzed for the four census regions. The distribution of benefits is found to differ widely between regions, indicating...

  8. Structural joint changes, malalignment, and laxity in osteoarthritis of the knee

    NARCIS (Netherlands)

    Esch, van der M.; Steultjens, M.P.; Wieringa, H.; Dinant, H.; Dekker, J.

    2005-01-01

    OBJECTIVE: To assess the relationship between (i) structural joint changes (i.e. joint space narrowing and osteophyte formation) and laxity and (ii) joint malalignment and laxity in osteoarthritis (OA) of the knee. METHODS: A cross-sectional study was carried out on 35 outpatients with

  9. Structural neuroimaging in preclinical dementia: From microstructural deficits and grey matter atrophy to macroscale connectomic changes.

    Science.gov (United States)

    Mak, Elijah; Gabel, Silvy; Mirette, Habib; Su, Li; Williams, Guy B; Waldman, Adam; Wells, Katie; Ritchie, Karen; Ritchie, Craig; O'Brien, John

    2017-05-01

    The last decade has witnessed a proliferation of neuroimaging studies characterising brain changes associated with Alzheimer's disease (AD), where both widespread atrophy and 'signature' brain regions have been implicated. In parallel, a prolonged latency period has been established in AD, with abnormal cerebral changes beginning many years before symptom onset. This raises the possibility of early therapeutic intervention, even before symptoms, when treatments could have the greatest effect on disease-course modification. Two important prerequisites of this endeavour are (1) accurate characterisation or risk stratification and (2) monitoring of progression using neuroimaging outcomes as a surrogate biomarker in those without symptoms but who will develop AD, here referred to as preclinical AD. Structural neuroimaging modalities have been used to identify brain changes related to risk factors for AD, such as familial genetic mutations, risk genes (for example apolipoprotein epsilon-4 allele), and/or family history. In this review, we summarise structural imaging findings in preclinical AD. Overall, the literature suggests early vulnerability in characteristic regions, such as the medial temporal lobe structures and the precuneus, as well as white matter tracts in the fornix, cingulum and corpus callosum. We conclude that while structural markers are promising, more research and validation studies are needed before future secondary prevention trials can adopt structural imaging biomarkers as either stratification or surrogate biomarkers. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Factor Structure and Sensitivity to Change of the Recovery Assessment Scale.

    Science.gov (United States)

    Jones, Salene M W; Ludman, Evette J

    2017-07-19

    The focus on recovery, not just symptom reduction, in mental health care brings a need for psychometrically sound measures of recovery. This study examined the factor structure and sensitivity to change of a common measure of mental health recovery, the Recovery Assessment Scale (RAS). We conducted a secondary data analysis from a randomized clinical trial of self-management for depression (n = 302). We tested both bifactor and the previously found five-factor model. Sensitivity to change was examined three ways: (1) between the intervention and control group; (2) across time in the intervention group; and (3) in those whose depression remitted. The previous five-factor model was supported. One subscale, no domination by symptoms, was particularly sensitive to change and showed sensitivity to change whereas the subscale reliance on others did not show change in any of the comparisons. Results suggest that the subscales of the RAS should be examined separately in future studies of recovery.

  11. The Associations between Regional Gray Matter Structural Changes and Changes of Cognitive Performance in Control Groups of Intervention Studies

    Science.gov (United States)

    Takeuchi, Hikaru; Taki, Yasuyuki; Sassa, Yuko; Sekiguchi, Atsushi; Nagase, Tomomi; Nouchi, Rui; Fukushima, Ai; Kawashima, Ryuta

    2015-01-01

    In intervention studies of cognitive training, the challenging cognitive tests, which were used as outcome measures, are generally completed in more than a few hours. Here, utilizing the control groups' data from three 1-week intervention studies in which young healthy adult subjects underwent a wide range of cognitive tests and T1-weighted magnetic resonance imaging (MRI) before and after the intervention period, we investigated how regional gray matter (GM) density (rGMD) of the subjects changed through voxel-based morphometry (VBM). Statistically significant increases in rGMD were observed in the anatomical cluster that mainly spread around the bilateral dorsal anterior cingulate cortex (dACC) and the right superior frontal gyrus (rSFG). Moreover, mean rGMD within this cluster changes were significantly and positively correlated with performance changes in the Stroop task, and tended to positively correlate with performance changes in a divergent thinking task. Affected regions are considered to be associated with performance monitoring (dACC) and manipulation of the maintained information including generating associations (rSFG), and both are relevant to the cognitive functions measured in the cognitive tests. Thus, the results suggest that even in the groups of the typical “control group” in intervention studies including those of the passive one, experimental or non-experimental factors can result in an increase in the regional GM structure and form the association between such neural changes and improvements related to these cognitive tests. These results suggest caution toward the experimental study designs without control groups. PMID:26733852

  12. Changes in molecular structure and properties of irradiated polymers of different compositions - ESR and NMR study

    International Nuclear Information System (INIS)

    Carswell-Pomerantz, T.; Babanalbandi, A.; Dong, L.; Hill, D.J.T.; Perera, M.C.S.; Pomery, P.J.; Saadat, G.; Whittaker, A.K.

    1999-01-01

    Investigations of molecular structural changes in polymers during exposure to high energy radiation is the long term interest of the Polymer Materials and Radiation Group at the University of Queensland. Recently, the group had looked at a range of polymers including natural and synthetic rubbers, methacrylates and polyesters. The objective of the work has been to investigate the relationships between polymer structure and sensitivity towards high energy radiation, including gamma radiation. This report will focus on the Electron Spin Resonance (ESR) and Nuclear Magnetic Resonance (NMR) studies of the effects of gamma irradiation on these polymers. Other methods such as Gas Chromatography (GC), Gel Permeation Chromatography (GPC), Fourier Transformed Infra Red (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA) and Dynamic Mechanical Analysis (DMA) have also been used as these methods combine with ESR and NMR, to provide a more complete picture of the mechanism of the structural changes. (author)

  13. Parametric imaging of collagen structural changes in human osteoarthritic cartilage using optical polarization tractography

    Science.gov (United States)

    Ravanfar, Mohammadreza; Pfeiffer, Ferris M.; Bozynski, Chantelle C.; Wang, Yuanbo; Yao, Gang

    2017-12-01

    Collagen degeneration is an important pathological feature of osteoarthritis. The purpose of this study is to investigate whether the polarization-sensitive optical coherence tomography (PSOCT)-based optical polarization tractography (OPT) can be useful in imaging collagen structural changes in human osteoarthritic cartilage samples. OPT eliminated the banding artifacts in conventional PSOCT by calculating the depth-resolved local birefringence and fiber orientation. A close comparison between OPT and PSOCT showed that OPT provided improved visualization and characterization of the zonal structure in human cartilage. Experimental results obtained in this study also underlined the importance of knowing the collagen fiber orientation in conventional polarized light microscopy assessment. In addition, parametric OPT imaging was achieved by quantifying the surface roughness, birefringence, and fiber dispersion in the superficial zone of the cartilage. These quantitative parametric images provided complementary information on the structural changes in cartilage, which can be useful for a comprehensive evaluation of collagen damage in osteoarthritic cartilage.

  14. Multilayer Mie Scattering Model for Investigation of Intracellular Structural Changes in the Nucleolus and Cytoplasm

    Directory of Open Access Journals (Sweden)

    S. Saltsberger

    2012-01-01

    Full Text Available Light scattering from biological cells has been used for many years as a diagnostic tool. Several simulation methods of the scattering process were developed in the last decades in order to understand and predict the scattering patterns. We developed an analytical model of a multilayer spherical scattering cell. Here, we describe the model and show that the results obtained within this simple method are similar to those obtained with far more complicated methods such as finite-difference time-domain (FDTD. The multilayer model is then used to study the effects of changes in the distribution of internal cell structures like mitochondria distribution or nucleus internal structures that exist in biological cells. Such changes are related with cancerous processes within the cell as well as other cell pathologies. Results show the ability to discriminate between different cell stages related to the mitochondria distributions and to internal structure of the nucleolus.

  15. Spin Structure Change in Co-Substituted BiFeO3

    Science.gov (United States)

    Yamamoto, Hajime; Kihara, Takumi; Oka, Kengo; Tokunaga, Masashi; Mibu, Ko; Azuma, Masaki

    2016-06-01

    The spin structure in BiFe1-xCoxO3 (x = 0.05,0.10,0.15,0.20) was investigated as a function of Co substitution, temperature, and magnetic field. It was found that the cycloidal spin structure of BiFeO3 changed to a collinear one with spin canting and composition-independent spontaneous magnetization of ˜0.25 μB/f.u. for the Co substituted samples on heating. The collinear phase was stabilized under magnetic fields. The spin structure change was clarified also by the temperature dependence of 57Fe Mössbauer spectra, and the results indicated the first order nature of this transition.

  16. Behavioral correlates of changes in hippocampal gray matter structure during acquisition of foreign vocabulary.

    Science.gov (United States)

    Bellander, Martin; Berggren, Rasmus; Mårtensson, Johan; Brehmer, Yvonne; Wenger, Elisabeth; Li, Tie-Qiang; Bodammer, Nils C; Shing, Yee-Lee; Werkle-Bergner, Markus; Lövdén, Martin

    2016-05-01

    Experience can affect human gray matter volume. The behavioral correlates of individual differences in such brain changes are not well understood. In a group of Swedish individuals studying Italian as a foreign language, we investigated associations among time spent studying, acquired vocabulary, baseline performance on memory tasks, and gray matter changes. As a way of studying episodic memory training, the language learning focused on acquiring foreign vocabulary and lasted for 10weeks. T1-weighted structural magnetic resonance imaging and cognitive testing were performed before and after the studies. Learning behavior was monitored via participants' use of a smartphone application dedicated to the study of vocabulary. A whole-brain analysis showed larger changes in gray matter structure of the right hippocampus in the experimental group (N=33) compared to an active control group (N=23). A first path analyses revealed that time spent studying rather than acquired knowledge significantly predicted change in gray matter structure. However, this association was not significant when adding performance on baseline memory measures into the model, instead only the participants' performance on a short-term memory task with highly similar distractors predicted the change. This measure may tap similar individual difference factors as those involved in gray matter plasticity of the hippocampus. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Alternative approaches used to assess structural changes of natural zircon caused by heat treatment

    Science.gov (United States)

    Huong, L. T. T.; Thuyet, N. T. M.; Phan, T. L.; Tran, N.; Toan, D. N.; Thang, P. D.; Huy, B. T.

    2018-03-01

    It is known that large changes in the crystal structure of zircon (ZrSiO4) can be assessed through the linewidth of the characteristic Raman mode (Δν3) at 1008 cm-1. However, the use of Δν3 to assess small changes caused by heat treatment at temperatures below its decomposition temperature of 1670 °C is difficult. The present work points out that the combination of X-ray diffraction (XRD) analyses, and photoluminescence (PL) and Raman (RS) measurements with different excitation wavelengths is an effective approach to solve the above problem. In this context, we have selected natural zircon containing some rare-earth (RE) impurities, and then studied the changes in its crystal structure caused by heat treatment at temperatures Tan=400-1600 °C. XRD analyses reveal that small modifications of the unit-cell parameters occur as Tan>600 °C. Taking the intensity ratios of the ν3 mode to RE-related emissions (Iν3/IRE) or the PL intensity ratios between RE-related emissions into consideration, the similar results in good agreement with the XRD analyses are also found. We believe that the small structural changes are related to the migration and redistribution of defects and impurities, and re-crystallization of zircon. This could be further confirmed though the relation between paramagnetic and ferromagnetic signals when Tan changes.

  18. The effects of demographic change on disease transmission and vaccine impact in a household structured population

    Directory of Open Access Journals (Sweden)

    Nicholas Geard

    2015-12-01

    Full Text Available The demographic structure of populations in both more developed and less developed countries is changing: increases in life expectancy and declining fertility have led to older populations and smaller households. The implications of these demographic changes for the spread and control of infectious diseases are not fully understood. Here we use an individual based model with realistic and dynamic age and household structure to demonstrate the marked effect that demographic change has on disease transmission at the population and household level. The decline in fertility is associated with a decrease in disease incidence and an increase in the age of first infection, even in the absence of vaccination or other control measures. Although large households become rarer as fertility decreases, we show that there is a proportionate increase in incidence of disease in these households as the accumulation of susceptible clusters increases the potential for explosive outbreaks. By modelling vaccination, we provide a direct comparison of the relative importance of demographic change and vaccination on incidence of disease. We highlight the increased risks associated with unvaccinated households in a low fertility setting if vaccine behaviour is correlated with household membership. We suggest that models that do not account for future demographic change, and especially its effect on household structure, may potentially overestimate the impact of vaccination.

  19. Density and Structural Change in Foreign Trade with The Middle East Border Countries

    Directory of Open Access Journals (Sweden)

    Mustafa Akal

    2008-12-01

    Full Text Available This study aims to outline export and import densities, advantageous and disadvantageous and comparative changes in product groups of traded goods of Turkey with the Middle East border countries in regard to the changes in production and economic structures of the countries from 1980 to 2005. The export density of Turkey changed from agricultural goods groups toward industrial good groups, from labor intensive good groups toward technology embodied capital intensive goods groups between 1980 and 2005. Turkey has had advantages in industrial goods, increased agricultural import and become more dependable in reducing energy gap in foreign trade with those countries since 1980, as a result of Turkey’s economic reforms and industrialization starting earlier than those border countries. However, there has been existing intra-industry trade in few industries including petroleum industry recently, It is concluded that the structural change in the types of traded goods groups densities is the result of the changes in the economic structures those countries

  20. The effects of demographic change on disease transmission and vaccine impact in a household structured population.

    Science.gov (United States)

    Geard, Nicholas; Glass, Kathryn; McCaw, James M; McBryde, Emma S; Korb, Kevin B; Keeling, Matt J; McVernon, Jodie

    2015-12-01

    The demographic structure of populations in both more developed and less developed countries is changing: increases in life expectancy and declining fertility have led to older populations and smaller households. The implications of these demographic changes for the spread and control of infectious diseases are not fully understood. Here we use an individual based model with realistic and dynamic age and household structure to demonstrate the marked effect that demographic change has on disease transmission at the population and household level. The decline in fertility is associated with a decrease in disease incidence and an increase in the age of first infection, even in the absence of vaccination or other control measures. Although large households become rarer as fertility decreases, we show that there is a proportionate increase in incidence of disease in these households as the accumulation of susceptible clusters increases the potential for explosive outbreaks. By modelling vaccination, we provide a direct comparison of the relative importance of demographic change and vaccination on incidence of disease. We highlight the increased risks associated with unvaccinated households in a low fertility setting if vaccine behaviour is correlated with household membership. We suggest that models that do not account for future demographic change, and especially its effect on household structure, may potentially overestimate the impact of vaccination. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  1. Structural Changes of the Macula on Optical Coherence Tomography after Vitrectomy for Proliferative Diabetic Retinopathy.

    Science.gov (United States)

    Im, Jong Chan; Kim, Jong Ho; Park, Dong Ho; Shin, Jae Pil

    2017-01-01

    This study aimed to evaluate the relationship between macular structural changes and visual prognosis after pars plana vitrectomy (PPV) for proliferative diabetic retinopathy. The study included 60 eyes that had undergone PPV. Macular optical coherence tomography (OCT) findings were classified into 5 groups preoperatively and 10 groups postoperatively. Best-corrected visual acuity (BCVA) were analyzed according to pre- and postoperative OCT. From the preoperative OCT, normal fovea with/without traction, normal fovea with preretinal hemorrhage, and tractional retinal detachment involving fovea showed an increase in BCVA after PPV (all p 20/50). Subfoveal fibrosis, macular hole, loss of foveal depression, and serous foveal detachment showed poor visual prognosis (BCVA <20/100). Macular structural changes were various after PPV, and visual prognosis correlated with these changes. © 2017 S. Karger AG, Basel.

  2. ABOUT THE SECTORAL AND TECHNOLOGICAL STRUCTURAL CHANGES NECESSARY FOR THE MODERNIZATION OF THE RUSSIAN ECONOMY

    Directory of Open Access Journals (Sweden)

    S. A. Akaeva

    2016-01-01

    Full Text Available This paper examines the effect of industry technological and structural changes on economic growth. It uses quantitative methods of structural changes evaluation by way of the Vatnik's proportionality constant as a means to analyze the dynamics of quality of sectoral and technological structures of the economies of Russia and several OECD countries. The comparative analysis shows that both the sectoral and technological structure of Russian economy is far from the optimal balanced structure of the OECD most developed countries' economies. It follows that Russian economy needs fundamental structural reform.Hence, the paper discusses the need for active industrial policy that can give impetus to the technological modernization of the Russian economy and facilitate its transition to the path of sustainable dynamic growth. The metallurgical, chemical and pharmaceutical industries are identified as priority sectors in industrial manufacturing. The paper analyzes condition and prospects of these industries and formulates medium-term goals of development and modernization, which can become reference points in the formation of a new sector-based industrial policy.

  3. A model study on changes and development of urban family structure in China.

    Science.gov (United States)

    Qiu, L

    1988-06-01

    To study the transitions and developing trends of China's urban families, a systematic survey was carried out in 1982-1983 in 5 cities: Beijing, Tianjin, Shanghai, Nanjing, and Chengdu. The survey covered 4385 families and 5075 married women. China's urban family structure has 2 significant features. 1st, the major forms of family structure are the nuclear family and the stem family, with former having a higher percentage. 2nd, nuclear families are increasing. The percentage of joint families has always been small. Many factors have an impact on changes in China's urban family structure, including economic income, housing conditions, household labor, life style and concepts, the difference between generations, and social flowing. Factors that directly affect urban family structure include family size, living arrangements, and whether or not any elderly live with the family. A mathematical model is developed to estimate family structure. The changes in China's family structure are characterized by 2 laws: 1) under the condition of a small percentage of joint families, the greater the number of children, the larger the size of the family's "social reproduction" will be. 2) Under the condition that most of the elderly are living with married children and the percentage of joint families are very small and decreasing, the greater the number of children, the more nuclear families there will be.

  4. Approaches to evaluation of changes in capital structure in industrial branches

    Directory of Open Access Journals (Sweden)

    Martin Landa

    2010-01-01

    Full Text Available Capital structure is described as a relation between equity and debts while the mutual consequences among items of company’s assets and resources employed as well as the cost of capital are also taken into account. Both, the theory and practice, at evaluation of approaches to capital structure are focu­sed on creation and optimization of capital structure. Relatively less frequent approach is the analy­sis of a state and of changes in capital structure on the level of whole business branch. But on this basis, it is possible to investigate some “average” approaches to selection of financial resources. At ca­pi­tal structure optimization (the proportion between equity and debts, a wide range of criteria plays a substantial role, e.g. cost of capital, risk, expected profitability, liquidity, dividend policy. These criteria have joint effect. This way, a logic question which criteria are preferred more and which criteria are preferred less appears. The article deals with the analysis of capital structure of three branches of manufacturing industry (the branch of production of plastics, the branch of production of electric equipments, the branch of production of textile in the years 2007–2009 with the special focus on development of financial structure, capital structure and on cost of capital.

  5. Structural-functional brain changes in depressed patients during and after electroconvulsive therapy.

    Science.gov (United States)

    Yrondi, Antoine; Péran, Patrice; Sauvaget, Anne; Schmitt, Laurent; Arbus, Christophe

    2018-02-01

    Electroconvulsive therapy (ECT) is a non-pharmacological treatment that is effective in treating severe and treatment-resistant depression. Although the efficacy of ECT has been demonstrated to treat major depressive disorder (MDD), the brain mechanisms underlying this process remain unclear. Structural-functional changes occur with the use of ECT as a treatment for depression based on magnetic resonance imaging (MRI). For this reason, we have tried to identify the changes that were identified by MRI to try to clarify some operating mechanisms of ECT. We focus to brain changes on MRI [structural MRI (sMRI), functional MRI (fMRI) and diffusion tensor imging (DTI)] after ECT. A systematic search of the international literature was performed using the bibliographic search engines PubMed and Embase. The research focused on papers published up to 30 September 2015. The following Medical Subject Headings (MESH) terms were used: electroconvulsive therapy AND (MRI OR fMRI OR DTI). Papers published in English were included. Four authors searched the database using a predefined strategy to identify potentially eligible studies. There were structural changes according to the sMRI performed before and after ECT treatment. These changes do not seem to be entirely due to oedema. This investigation assessed the functional network connectivity associated with the ECT response in MDD. ECT response reverses the relationship from negative to positive between the two pairs of networks. We found structural-functional changes in MRI post-ECT. Because of the currently limited MRI data on ECT in the literature, it is necessary to conduct further investigations using other MRI technology.

  6. Evaluating Structural Change Approaches to Health Promotion: An Exploratory Scoping Review of a Decade of U.S. Progress

    Science.gov (United States)

    Asada, Yuka; Lieberman, Lisa D.; Neubauer, Leah C.; Hanneke, Rosie; Fagen, Michael C.

    2018-01-01

    Structural change approaches--also known as policy and environmental changes--are becoming increasingly common in health promotion, yet our understanding of how to evaluate them is still limited. An exploratory scoping review of the literature was conducted to understand approaches and methods used to evaluate structural change interventions in…

  7. Change Analysis in Structural Laser Scanning Point Clouds: The Baseline Method.

    Science.gov (United States)

    Shen, Yueqian; Lindenbergh, Roderik; Wang, Jinhu

    2016-12-24

    A method is introduced for detecting changes from point clouds that avoids registration. For many applications, changes are detected between two scans of the same scene obtained at different times. Traditionally, these scans are aligned to a common coordinate system having the disadvantage that this registration step introduces additional errors. In addition, registration requires stable targets or features. To avoid these issues, we propose a change detection method based on so-called baselines. Baselines connect feature points within one scan. To analyze changes, baselines connecting corresponding points in two scans are compared. As feature points either targets or virtual points corresponding to some reconstructable feature in the scene are used. The new method is implemented on two scans sampling a masonry laboratory building before and after seismic testing, that resulted in damages in the order of several centimeters. The centres of the bricks of the laboratory building are automatically extracted to serve as virtual points. Baselines connecting virtual points and/or target points are extracted and compared with respect to a suitable structural coordinate system. Changes detected from the baseline analysis are compared to a traditional cloud to cloud change analysis demonstrating the potential of the new method for structural analysis.

  8. Change Analysis in Structural Laser Scanning Point Clouds: The Baseline Method

    Directory of Open Access Journals (Sweden)

    Yueqian Shen

    2016-12-01

    Full Text Available A method is introduced for detecting changes from point clouds that avoids registration. For many applications, changes are detected between two scans of the same scene obtained at different times. Traditionally, these scans are aligned to a common coordinate system having the disadvantage that this registration step introduces additional errors. In addition, registration requires stable targets or features. To avoid these issues, we propose a change detection method based on so-called baselines. Baselines connect feature points within one scan. To analyze changes, baselines connecting corresponding points in two scans are compared. As feature points either targets or virtual points corresponding to some reconstructable feature in the scene are used. The new method is implemented on two scans sampling a masonry laboratory building before and after seismic testing, that resulted in damages in the order of several centimeters. The centres of the bricks of the laboratory building are automatically extracted to serve as virtual points. Baselines connecting virtual points and/or target points are extracted and compared with respect to a suitable structural coordinate system. Changes detected from the baseline analysis are compared to a traditional cloud to cloud change analysis demonstrating the potential of the new method for structural analysis.

  9. Temperate mountain forest biodiversity under climate change: compensating negative effects by increasing structural complexity.

    Science.gov (United States)

    Braunisch, Veronika; Coppes, Joy; Arlettaz, Raphaël; Suchant, Rudi; Zellweger, Florian; Bollmann, Kurt

    2014-01-01

    Species adapted to cold-climatic mountain environments are expected to face a high risk of range contractions, if not local extinctions under climate change. Yet, the populations of many endothermic species may not be primarily affected by physiological constraints, but indirectly by climate-induced changes of habitat characteristics. In mountain forests, where vertebrate species largely depend on vegetation composition and structure, deteriorating habitat suitability may thus be mitigated or even compensated by habitat management aiming at compositional and structural enhancement. We tested this possibility using four cold-adapted bird species with complementary habitat requirements as model organisms. Based on species data and environmental information collected in 300 1-km2 grid cells distributed across four mountain ranges in central Europe, we investigated (1) how species' occurrence is explained by climate, landscape, and vegetation, (2) to what extent climate change and climate-induced vegetation changes will affect habitat suitability, and (3) whether these changes could be compensated by adaptive habitat management. Species presence was modelled as a function of climate, landscape and vegetation variables under current climate; moreover, vegetation-climate relationships were assessed. The models were extrapolated to the climatic conditions of 2050, assuming the moderate IPCC-scenario A1B, and changes in species' occurrence probability were quantified. Finally, we assessed the maximum increase in occurrence probability that could be achieved by modifying one or multiple vegetation variables under altered climate conditions. Climate variables contributed significantly to explaining species occurrence, and expected climatic changes, as well as climate-induced vegetation trends, decreased the occurrence probability of all four species, particularly at the low-altitudinal margins of their distribution. These effects could be partly compensated by modifying

  10. Temperate mountain forest biodiversity under climate change: compensating negative effects by increasing structural complexity.

    Directory of Open Access Journals (Sweden)

    Veronika Braunisch

    Full Text Available Species adapted to cold-climatic mountain environments are expected to face a high risk of range contractions, if not local extinctions under climate change. Yet, the populations of many endothermic species may not be primarily affected by physiological constraints, but indirectly by climate-induced changes of habitat characteristics. In mountain forests, where vertebrate species largely depend on vegetation composition and structure, deteriorating habitat suitability may thus be mitigated or even compensated by habitat management aiming at compositional and structural enhancement. We tested this possibility using four cold-adapted bird species with complementary habitat requirements as model organisms. Based on species data and environmental information collected in 300 1-km2 grid cells distributed across four mountain ranges in central Europe, we investigated (1 how species' occurrence is explained by climate, landscape, and vegetation, (2 to what extent climate change and climate-induced vegetation changes will affect habitat suitability, and (3 whether these changes could be compensated by adaptive habitat management. Species presence was modelled as a function of climate, landscape and vegetation variables under current climate; moreover, vegetation-climate relationships were assessed. The models were extrapolated to the climatic conditions of 2050, assuming the moderate IPCC-scenario A1B, and changes in species' occurrence probability were quantified. Finally, we assessed the maximum increase in occurrence probability that could be achieved by modifying one or multiple vegetation variables under altered climate conditions. Climate variables contributed significantly to explaining species occurrence, and expected climatic changes, as well as climate-induced vegetation trends, decreased the occurrence probability of all four species, particularly at the low-altitudinal margins of their distribution. These effects could be partly compensated

  11. Changes in the chemical structure of polytetrafluoroethylene induced by electron beam irradiation in the molten state

    CERN Document Server

    Lappan, U; Lunkwitz, K

    2000-01-01

    Polytetrafluoroethylene (PTFE) was exposed to electron beam radiation at elevated temperature above the melting point under nitrogen atmosphere and in vacuum for comparison. Fourier-transform infrared (FTIR) spectroscopy was used to study the changes in the chemical structure. The irradiation under nitrogen atmosphere leads to the same structures as described recently for PTFE irradiated in vacuum. Trifluoromethyl branches and double bond structures were detected. The concentrations of terminal and internal double bonds are higher after irradiation under nitrogen than in vacuum. Annealing experiments have shown that the thermal oxidative stability of the radiation-modified PTFE is reduced compared to unirradiated PTFE. The reason are the formation of unstable structures such as double bonds.

  12. Colocalized structural and functional changes in the cortex of patients with trigeminal neuropathic pain.

    Directory of Open Access Journals (Sweden)

    Alexandre F DaSilva

    Full Text Available Recent data suggests that in chronic pain there are changes in gray matter consistent with decreased brain volume, indicating that the disease process may produce morphological changes in the brains of those affected. However, no study has evaluated cortical thickness in relation to specific functional changes in evoked pain. In this study we sought to investigate structural (gray matter thickness and functional (blood oxygenation dependent level - BOLD changes in cortical regions of precisely matched patients with chronic trigeminal neuropathic pain (TNP affecting the right maxillary (V2 division of the trigeminal nerve. The model has a number of advantages including the evaluation of specific changes that can be mapped to known somatotopic anatomy.Cortical regions were chosen based on sensory (Somatosensory cortex (SI and SII, motor (MI and posterior insula, or emotional (DLPFC, Frontal, Anterior Insula, Cingulate processing of pain. Both structural and functional (to brush-induced allodynia scans were obtained and averaged from two different imaging sessions separated by 2-6 months in all patients. Age and gender-matched healthy controls were also scanned twice for cortical thickness measurement. Changes in cortical thickness of TNP patients were frequently colocalized and correlated with functional allodynic activations, and included both cortical thickening and thinning in sensorimotor regions, and predominantly thinning in emotional regions.Overall, such patterns of cortical thickness suggest a dynamic functionally-driven plasticity of the brain. These structural changes, which correlated with the pain duration, age-at-onset, pain intensity and cortical activity, may be specific targets for evaluating therapeutic interventions.

  13. Switch region for pathogenic structural change in conformational disease and its prediction.

    Directory of Open Access Journals (Sweden)

    Xin Liu

    2010-01-01

    Full Text Available Many diseases are believed to be related to abnormal protein folding. In the first step of such pathogenic structural changes, misfolding occurs in regions important for the stability of the native structure. This destabilizes the normal protein conformation, while exposing the previously hidden aggregation-prone regions, leading to subsequent errors in the folding pathway. Sites involved in this first stage can be deemed switch regions of the protein, and can represent perfect binding targets for drugs to block the abnormal folding pathway and prevent pathogenic conformational changes. In this study, a prediction algorithm for the switch regions responsible for the start of pathogenic structural changes is introduced. With an accuracy of 94%, this algorithm can successfully find short segments covering sites significant in triggering conformational diseases (CDs and is the first that can predict switch regions for various CDs. To illustrate its effectiveness in dealing with urgent public health problems, the reason of the increased pathogenicity of H5N1 influenza virus is analyzed; the mechanisms of the pandemic swine-origin 2009 A(H1N1 influenza virus in overcoming species barriers and in infecting large number of potential patients are also suggested. It is shown that the algorithm is a potential tool useful in the study of the pathology of CDs because: (1 it can identify the origin of pathogenic structural conversion with high sensitivity and specificity, and (2 it provides an ideal target for clinical treatment.

  14. Hardness and structure changes at surface in electrical discharge machined steel C 3840

    International Nuclear Information System (INIS)

    Karastojkovic, Z.; Janjusevic, Z.

    2003-01-01

    The electrical discharge machining (EDM) of both hard and soft materials became an important technique in industrial applications. This technique has an advantage in producing of structural/tool parts of complex geometry. The EDM is based on electrical phenomena, when the treated surface undergoes to erosion. The first step in EDM, the melting of thin surface layer, frequently is neglected. In this paper the changes of hardness and structure at surface layer, after EDM is applied on steel C 3840, will be discussed. The steel C- 3840 was quenched and tempered to hardness of 63 HRC, at surface, and than machined by electrical discharging. The changed, white, layer is just a product of melting and decarburization processes. The white layer is registered at surface by using a metallographic investigation. Hardness profile is measured from surface to the interior of material. The achievement of local high temperatures during EDM is resulting on melt and erosion of material. Besides of these effects, during EDM were happened some minor but not a neglectible effects, primary on structure changes on treated surface. It would be expected that melting, even an evaporation of melted metal, and further the phase transformation have an important influence on the starting structure. (Original)

  15. Influence of Weaving Loom Setting Parameters on Changes of Woven Fabric Structure and Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Aušra ADOMAITIENĖ

    2011-11-01

    Full Text Available During the manufacturing of fabric of different raw material there was noticed, that after removing the fabric from weaving loom and after stabilization of fabric structure, the changes of parameters of fabric structure are not regular. During this investigation it was analysed, how weaving loom technological parameters (heald cross moment and initial tension of warp should be chosen and how to predict the changes of fabric structure parameters and its mechanical properties. The dependencies of changes of half-wool fabric structure parameters (weft setting, fabric thickness and projections of fabric cross-section and mechanical properties (breaking force, elongation at break, static friction force and static friction coefficient on weaving loom setting parameters (heald cross moment and initial warp tension were analysed. The orthogonal Box plan of two factors was used, the 3-D dependencies were drawn, and empirical equations of these dependencies were established.http://dx.doi.org/10.5755/j01.ms.17.4.780

  16. Searching for structural medium changes during the 2011 El Hierro (Spain) submarine eruption

    Science.gov (United States)

    Sánchez-Pastor, Pilar S.; Schimmel, Martin; López, Carmen

    2017-04-01

    Submarine volcanic eruptions are often difficult to study due to their restricted access that usually inhibits direct observations. That happened with the 2011 El Hierro eruption, which is the first eruption that has been tracked in real time in Canary Islands. For instance, despite the real-time tracking it was not possible to determine the exact end of the eruption. Besides, volcanic eruptions involve many dynamic (physical and chemical) processes, which cause structural changes in the surrounding medium that we expect to observe and monitor through passive seismic approaches. The purpose of this study is to detect and analyse these changes as well as to search for precursory signals to the eruption itself using ambient noise auto and cross-correlations. We employ different correlation strategies (classical and phase cross-correlation) and apply them to field data recorded by the IGN network during 2011 and 2012. The different preprocessing and processing steps are tested and compared to better understand the data, to find the robust signatures, and to define a routine work procedure. One of the problems we face is the presence of volcanic tremors, which cause a varying seismic response that we can not attribute to structural changes. So far, structural changes could not be detected unambiguously and we present our ongoing research in this field.

  17. Assessment of structural changes of human teeth by low-field nuclear magnetic resonance (NMR)

    International Nuclear Information System (INIS)

    Ni, Qingwen; Chen, Shuo

    2010-01-01

    A technique of low-field pulsed proton nuclear magnetic resonance (NMR) spin relaxation is described for assessment of age-related structural changes (dentin and pulp) of human teeth in vitro. The technique involves spin–spin relaxation measurement and inversion spin–spin spectral analysis methods. The spin–spin relaxation decay curve is converted into a T 2 distribution spectrum by a sum of single exponential decays. The NMR spectra from the extracted dentin-portion-only and dental pulp-cells-only were compared with the whole extracted teeth spectra, for the dentin and pulp peak assignments. While dentin and pulp are highly significant parameters in determining tooth quality, variations in these parameters with age can be used as an effective tool for estimating tooth quality. Here we propose an NMR calibration method—the ratio of the amount of dentin to the amount of pulp obtained from NMR T 2 distribution spectra can be used for measuring the age-related structural changes in teeth while eliminating any variations in size of teeth. Eight teeth (third molars) extracted from humans, aged among 17–67 years old, were tested in this study. It is found that the intensity ratio of dentin to pulp sensitively changes from 0.48 to 3.2 approaching a linear growth with age. This indicates that age-related structural changes in human teeth can be detected using the low-field NMR technique

  18. Main drivers of changes in CO2 emissions in the Spanish economy: A structural decomposition analysis

    International Nuclear Information System (INIS)

    Cansino, José M.; Román, Rocío; Ordóñez, Manuel

    2016-01-01

    The aim of this paper is the analysis of structural decomposition of changes in CO 2 emissions in Spain by using an enhanced Structural Decomposition Analysis (SDA) supported by detailed Input–Output tables from the World Input–Output Database (2013) (WIOD) for the period 1995–2009. The decomposition of changes in CO 2 emissions at sectoral level are broken down into six effects: carbonization, energy intensity, technology, structural demand, consumption pattern and scale. The results are interesting, not only for researchers but also for utility companies and policy-makers as soon as past and current political mitigation measures are analyzed in line with such results. The results allow us to conclude that the implementation of the Kyoto Protocol together with European Directives related to the promotion of RES seem to have a positive impact on CO 2 emissions trends in Spain. After reviewing the current mitigation measures in Spain, one policy recommendation is suggested to avoid the rebound effect and to enhance the fight against Climate Change that is tax benefits for those companies that prove reductions in their energy intensity ratios. - Highlights: • Kyoto's Protocol and European Directives acted against CO 2 emissions in Spain. • Changes in primary energy mix acted against increasing CO 2 emissions. • Energy efficiency seems to have improved. • Historical analysis gives support for most mitigation measures currently in force.

  19. Robustness of Pluronic Block Copolymer Nanostructure to Structural Changes in Dispersed Nanoparticles

    Science.gov (United States)

    Lafollette, Theresa A.; Walker, Lynn M.

    2009-03-01

    Thermoreversible block copolymers [(PEO)n-(PPO)m-(PEO)n; trade name Pluronic] self assemble into ordered micelle gels. Nanoparticles (3-10nm) are templated in the interstitial spaces of Pluronic micelle gels to form nanocomposite systems. Globular hydrophilic proteins have served as model monodisperse nanoparticles in this work. We have shown that these proteins are templated in the interstitial sites of the cubic packed micelle gels at room temperature. By raising the temperature, the proteins are denatured to study the robustness of the micelle gel to structural changes due to the unfolded protein. Nanoscale structure is determined from small angle neutron scattering (SANS). It was expected that any change in the nanoparticle size would cause a change in the packing of the Pluronic micelle gel. However in SANS experiments, the FCC and BCC Pluronic templates show no nanoscale structural differences between a room temperature sample and a sample that has been heated to denature the protein and then cooled back to room temperature. There is a change in the template at longer length scales as evidenced by a low q upturn in the scattered intensity. The robustness of the micelle gel at different length scales will be discussed.

  20. Climate-induced changes in lake ecosystem structure inferred from coupled neo- and paleoecological approaches

    Science.gov (United States)

    Saros, Jasmine E.; Stone, Jeffery R.; Pederson, Gregory T.; Slemmons, Krista; Spanbauer, Trisha; Schliep, Anna; Cahl, Douglas; Williamson, Craig E.; Engstrom, Daniel R.

    2015-01-01

    Over the 20th century, surface water temperatures have increased in many lake ecosystems around the world, but long-term trends in the vertical thermal structure of lakes remain unclear, despite the strong control that thermal stratification exerts on the biological response of lakes to climate change. Here we used both neo- and paleoecological approaches to develop a fossil-based inference model for lake mixing depths and thereby refine understanding of lake thermal structure change. We focused on three common planktonic diatom taxa, the distributions of which previous research suggests might be affected by mixing depth. Comparative lake surveys and growth rate experiments revealed that these species respond to lake thermal structure when nitrogen is sufficient, with species optima ranging from shallower to deeper mixing depths. The diatom-based mixing depth model was applied to sedimentary diatom profiles extending back to 1750 AD in two lakes with moderate nitrate concentrations but differing climate settings. Thermal reconstructions were consistent with expected changes, with shallower mixing depths inferred for an alpine lake where treeline has advanced, and deeper mixing depths inferred for a boreal lake where wind strength has increased. The inference model developed here provides a new tool to expand and refine understanding of climate-induced changes in lake ecosystems.

  1. A longitudinal study of structural brain network changes with normal aging

    Directory of Open Access Journals (Sweden)

    Kai eWu

    2013-04-01

    Full Text Available The aim of this study was to investigate age-related changes in the topological organization of structural brain networks by applying a longitudinal design over 6 years. Structural brain networks were derived from measurements of regional gray matter volume and were constructed in age-specific groups from baseline and follow-up scans. The structural brain networks showed economical small-world properties, providing high global and local efficiency for parallel information processing at low connection costs. In the analysis of the global network properties, the local and global efficiency of the baseline scan were significantly lower compared to the follow-up scan. Moreover, the annual rate of changes in local and global efficiency showed a positive and negative quadratic correlation with the baseline age, respectively; both curvilinear correlations peaked at approximately the age of 50. In the analysis of the regional nodal properties, significant negative correlations between the annual rate of changes in nodal strength and the baseline age were found in the brain regions primarily involved in the visual and motor/ control systems, whereas significant positive quadratic correlations were found in the brain regions predominately associated with the default-mode, attention, and memory systems. The results of the longitudinal study are consistent with the findings of our previous cross-sectional study: the structural brain networks develop into a fast distribution from young to middle age (approximately 50 years old and eventually became a fast localization in the old age. Our findings elucidate the network topology of structural brain networks and its longitudinal changes, thus enhancing the understanding of the underlying physiology of normal aging in the human brain.

  2. Homeostatic structural plasticity can account for topology changes following deafferentation and focal stroke.

    Science.gov (United States)

    Butz, Markus; Steenbuck, Ines D; van Ooyen, Arjen

    2014-01-01

    After brain lesions caused by tumors or stroke, or after lasting loss of input (deafferentation), inter- and intra-regional brain networks respond with complex changes in topology. Not only areas directly affected by the lesion but also regions remote from the lesion may alter their connectivity-a phenomenon known as diaschisis. Changes in network topology after brain lesions can lead to cognitive decline and increasing functional disability. However, the principles governing changes in network topology are poorly understood. Here, we investigated whether homeostatic structural plasticity can account for changes in network topology after deafferentation and brain lesions. Homeostatic structural plasticity postulates that neurons aim to maintain a desired level of electrical activity by deleting synapses when neuronal activity is too high and by providing new synaptic contacts when activity is too low. Using our Model of Structural Plasticity, we explored how local changes in connectivity induced by a focal loss of input affected global network topology. In accordance with experimental and clinical data, we found that after partial deafferentation, the network as a whole became more random, although it maintained its small-world topology, while deafferentated neurons increased their betweenness centrality as they rewired and returned to the homeostatic range of activity. Furthermore, deafferentated neurons increased their global but decreased their local efficiency and got longer tailed degree distributions, indicating the emergence of hub neurons. Together, our results suggest that homeostatic structural plasticity may be an important driving force for lesion-induced network reorganization and that the increase in betweenness centrality of deafferentated areas may hold as a biomarker for brain repair.

  3. Structural changes and degradation of Red Latosols under different management systems for 20 years

    Directory of Open Access Journals (Sweden)

    João Tavares Filho

    2014-08-01

    Full Text Available Soils are the foundation of terrestrial ecosystems and their role in food production is fundamental, although physical degradation has been observed in recent years, caused by different cultural practices that modify structures and consequently the functioning of soils. The objective of this study was to evaluate possible structural changes and degradation in an Oxisol under different managements for 20 years: no-tillage cultivation with and without crop rotation, perennial crop and conventional tillage, plus a forested area (reference. Initially, the crop profile was described and subsequently, 10 samples per management system and forest soil were collected to quantify soil organic matter, flocculation degree, bulk density, and macroporosity. The results indicated structural changes down to a soil depth of 50 cm, with predominance of structural units ∆μ (intermediate compaction level under perennial crop and no-tillage crop rotation, and of structural units ∆ (compacted under conventional tillage and no-tillage. The soil was increasingly degraded in the increasing order: forest => no-tillage crop rotation => perennial crop => no-tillage without crop rotation => conventional tillage. In all managements, the values of organic matter and macroporosity were always below and bulk density always above those of the reference area (forest and, under no-tillage crop rotation and perennial crop, the flocculation degree was proportionally equal to that of the reference area.

  4. Structural changes of the oxygen-evolving complex in photosystem II during the catalytic cycle.

    Science.gov (United States)

    Glöckner, Carina; Kern, Jan; Broser, Matthias; Zouni, Athina; Yachandra, Vittal; Yano, Junko

    2013-08-02

    The oxygen-evolving complex (OEC) in the membrane-bound protein complex photosystem II (PSII) catalyzes the water oxidation reaction that takes place in oxygenic photosynthetic organisms. We investigated the structural changes of the Mn4CaO5 cluster in the OEC during the S state transitions using x-ray absorption spectroscopy (XAS). Overall structural changes of the Mn4CaO5 cluster, based on the manganese ligand and Mn-Mn distances obtained from this study, were incorporated into the geometry of the Mn4CaO5 cluster in the OEC obtained from a polarized XAS model and the 1.9-Å high resolution crystal structure. Additionally, we compared the S1 state XAS of the dimeric and monomeric form of PSII from Thermosynechococcus elongatus and spinach PSII. Although the basic structures of the OEC are the same for T. elongatus PSII and spinach PSII, minor electronic structural differences that affect the manganese K-edge XAS between T. elongatus PSII and spinach PSII are found and may originate from differences in the second sphere ligand atom geometry.

  5. Changes of creatine kinase structure upon ligand binding as seen by small-angle scattering

    Science.gov (United States)

    Forstner, Michael; Kriechbaum, Manfred; Laggner, Peter; Wallimann, Theo

    1996-09-01

    Small-angle X-ray and neutron scattering have been used to investigate structural changes upon binding of individual substrates or a transition state analogue complex (TSAC), consisting of Mg-ADP, creatine and KNO 3 to creatine kinase isoenzymes (dimeric M-CK and octameric Mi-CK) and monomeric arginine kinase (AK). Considerable changes in the shape and the size of the molecules occurred upon binding of Mg-ATP and TSAC, whereas creatine alone had only a small effect. In Mi-CK, the radius of gyration was reduced from 55.6 Å (free enzyme) to 48.9 Å (enzyme + Mg-ATP) and to 48.2 Å (enzyme + TSAC). The experiments performed with M-CK showed similar changes from 28.0 Å (free enzyme) to 25.6 Å (enzyme + Mg-ATP) and to 25.5 Å (enzyme + TSAC). Creatine alone did not lead to significant changes in the radii of gyration, nor did free ATP or ADP. AK showed the same behaviour: a change of the radius of gyration from 21.5 Å (free enzyme) to 19.7 Å (enzyme + MG-ATP), whereas with arginine alone only a minor change could be observed. The primary change in structure as seen with monomeric AK seems to be a magnesium-nucleotide induced domain movement relative to each other, whereas the effect of substrate may be of local order only. In creatine kinase, however, further movements must be involved in the large conformational change.

  6. From bifluorenylidene dianion to dibenzo[g,p]chrysene dianion: sensitivity of anisotropy changes to bonding structure

    DEFF Research Database (Denmark)

    Shenhar, R.; Beust, R.; Hagen, Stefan

    2002-01-01

    Five polycyclic aromatic hydrocarbons of the C-26 series having similar bonding structure yield dianions upon reduction with lithium metal. Anisotropy changes, revealed from an advanced charge distribution analysis performed on these dianions, show a correlation to the bonding structure...

  7. MR imaging of lumbar spondylolysis: signal intensity change in the pars interarticularis and adjacent structures

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Suk Whan; Lee, Ghi Jai; Shim, Jae Chan; Kim, Ho Kyun [Inje Univ. College of Medicine, Kimhae (Korea, Republic of)

    2001-05-01

    To assess changes in MR signal intensity in the pars interarticularis and adjacent structures in patients with lumbar spondylolysis. The MR images of 36 patients with lumbar spondylolysis, confirmed by plain radiographs, were retrospectively analyzed. Using a 1.0T unit, we evaluated the signal intensity of a total of 216 parts interarticulares and adjacent structures from L3 to L5, as seen on sagittal images, and differences between areas with and without spondylolysis. The signal intensity of T1-and T2-weighted images was graded 0(more hypointense than spinal body), 1(as isointense as spinal body), 2(more hyperintense than spinal body and more hypointense than epidural fat), or 3(as isointense as epidural fat). Signal intensity change in endplates and degree of spondylolisthesis were analyzed, and the relationship between these factors was determined. Spondylolysis was noted at L5 in 61 cases, at L4 in 22, and of L3 in no case. In three cases spondylolysis was unilateral, and in the remainder it was bilateral. The degree of signal intensity was the same on T1-and T2-weighted images, and no case was grade 0. Eighty-six of 133 areas without spondylolysis were grade 1, 43 were grade 2, and four were grade 3. In 42 of 47 cases, signal intensity change was localized at pedicles. Among 83 areas with spondylolysis,on the other hand, nine were grade 1, 48 were grade 2, and 26 were grade 3. Signal intensity change was most commonly observed at the pars interarticularis, pedicle, and lamina(50/74)({rho}<0.001). Signal intensity change at the pars interarticularis and adjacent structures was accompanied in most cases by degenerative endplate change(10/11) and spondylolisthesis(11/13)({rho}<0.001). In patients with spondylolysis, signal intensity was frequently higher at the pars interarticularis and adjacent structures, and is thought to have a close relationship with degenerative endplate change and spondylolisthesis. Increases in signal intensity at the pars

  8. MR imaging of lumbar spondylolysis: signal intensity change in the pars interarticularis and adjacent structures

    International Nuclear Information System (INIS)

    Jang, Suk Whan; Lee, Ghi Jai; Shim, Jae Chan; Kim, Ho Kyun

    2001-01-01

    To assess changes in MR signal intensity in the pars interarticularis and adjacent structures in patients with lumbar spondylolysis. The MR images of 36 patients with lumbar spondylolysis, confirmed by plain radiographs, were retrospectively analyzed. Using a 1.0T unit, we evaluated the signal intensity of a total of 216 parts interarticulares and adjacent structures from L3 to L5, as seen on sagittal images, and differences between areas with and without spondylolysis. The signal intensity of T1-and T2-weighted images was graded 0(more hypointense than spinal body), 1(as isointense as spinal body), 2(more hyperintense than spinal body and more hypointense than epidural fat), or 3(as isointense as epidural fat). Signal intensity change in endplates and degree of spondylolisthesis were analyzed, and the relationship between these factors was determined. Spondylolysis was noted at L5 in 61 cases, at L4 in 22, and of L3 in no case. In three cases spondylolysis was unilateral, and in the remainder it was bilateral. The degree of signal intensity was the same on T1-and T2-weighted images, and no case was grade 0. Eighty-six of 133 areas without spondylolysis were grade 1, 43 were grade 2, and four were grade 3. In 42 of 47 cases, signal intensity change was localized at pedicles. Among 83 areas with spondylolysis,on the other hand, nine were grade 1, 48 were grade 2, and 26 were grade 3. Signal intensity change was most commonly observed at the pars interarticularis, pedicle, and lamina(50/74)(ρ<0.001). Signal intensity change at the pars interarticularis and adjacent structures was accompanied in most cases by degenerative endplate change(10/11) and spondylolisthesis(11/13)(ρ<0.001). In patients with spondylolysis, signal intensity was frequently higher at the pars interarticularis and adjacent structures, and is thought to have a close relationship with degenerative endplate change and spondylolisthesis. Increases in signal intensity at the pars interarticularis and

  9. IMPACT OF CHANGES IN A PROJECT TEAM STRUCTURE ON THE TEAM PERFORMANCE

    OpenAIRE

    Šandrk Nukić, Ivana; Galić, Mario; Dolaček-Alduk, Zlata

    2015-01-01

    Structuring a project team is highly sensitive task, so numerous methods which address the problem have emerged. One of the most effective methods is structuring teams by the team members’ affinities and talents presented as team roles. In this paper, we applied Belbin’s Self-Perception Inventory in order to investigate the following questions: Which are the most engaged team roles? How does the absence of the most engaged team members affect the team’s efficiency? How does this change of the...

  10. Changes in attitude structure toward nuclear power in the nuclear power plant locations of Tohoku district

    International Nuclear Information System (INIS)

    Tsujikawa, Norifumi; Tsuchida, Shoji; Shiotani, Takamasa; Nakagawa, Yuri

    2012-01-01

    This survey was examined the changes in structure of attitude toward nuclear power and the influence of environmental value on the attitude structure before and after the accident at the Fukushima No. 1 nuclear power plant. With residents of Aomori, Miyagi, and Fukushima prefectures as participants, we conducted online surveys in November 2009 and October 2011. Comparing the results before and after the accident, we found that trust in the management of nuclear power plants had a stronger influence on the perceived risk and benefit regarding nuclear power after the accident than before the accident. The value of concern about environmental destruction resulted in reduced trust in the management. (author)

  11. Quantitative description of changes in the structure in austenitic steels after hot temperature deformation

    International Nuclear Information System (INIS)

    Kuc, D.; Rodak, K.; Niewielski, G.; Hetmanczyk, M.

    1998-01-01

    An investigation on the structural changes in austenitic hard deformable Cr-Mn and Cr-Ni steels during dynamic recrystallization has been presented in the paper. The influence of the factors (strain rate, deformation, temperature) on the geometric characteristic of grains has been taken into consideration. Investigation of the structure were performed using metallographic microscope and transmission electron microscope. The results of researched should widen the theoretical background in order to the model of phenomena, which accompany the dynamic recovery and dynamic recrystallization. (author)

  12. Why has the energy intensity fallen in China's industrial sector in the 1990s? : the relative importance of structural change and intensity change

    NARCIS (Netherlands)

    Zhang, Zhong Xiang

    2001-01-01

    Abstract There have been a variety of studies investigating the relative importance of structural change and real intensity change to the change in China’s energy consumption in the 1980s. However, no detailed analysis to date has been done to examine whether or not the increased energy efficiency

  13. Relationship between ultrasonic properties and structural changes in the mesophyll during leaf dehydration.

    Science.gov (United States)

    Sancho-Knapik, Domingo; Alvarez-Arenas, Tomás Gómez; Peguero-Pina, José Javier; Fernández, Victoria; Gil-Pelegrín, Eustaquio

    2011-06-01

    The broad-band ultrasonic spectroscopy technique allows the determination of changes in the relative water content (RWC) of leaves with contrasting structural features. Specifically, the standardized frequency associated with the maximum transmittance (f/f(o)) is strongly related to the RWC. This relationship is characterized by the existence of two phases separated by an inflexion point (associated with the turgor loss point). To obtain a better understanding of the strong relationship found between RWC and f/f(o), this work has studied the structural changes experienced by Quercus muehlenbergii leaves during dehydration in terms of ultrasounds measurements, cell wall elasticity, leaf thickness, leaf density, and leaf structure. The results suggest that the decrease found in f/f(o) before the turgor loss point can be attributed to the occurrence of changes in the estimation of the macroscopic effective elastic constant of the leaf (c(33)), mainly associated with changes in the bulk modulus of elasticity of the cell wall (ε). These changes are overriding or compensating for the thickness decreases recorded during this phase. On the other hand, the high degree of cell shrinkage and stretching found in the mesophyll cells during the second phase seem to explain the changes in the acoustic properties of the leaf beyond the turgor loss point. The formation of large intercellular spaces, which increased the irregularity in the acoustic pathway, may explain the increase of the attenuation coefficient of ultrasounds once the turgor loss point threshold is exceeded. The direct measurement of c(33) from ultrasonic measurements would allow a better knowledge of the overall biomechanical properties of the leaf further than those derived from the P-V analysis.

  14. Seasonal changes in colour: a comparison of structural, melanin- and carotenoid-based plumage colours.

    Directory of Open Access Journals (Sweden)

    Kaspar Delhey

    Full Text Available BACKGROUND: Plumage coloration is important for bird communication, most notably in sexual signalling. Colour is often considered a good quality indicator, and the expression of exaggerated colours may depend on individual condition during moult. After moult, plumage coloration has been deemed fixed due to the fact that feathers are dead structures. Still, many plumage colours change after moult, although whether this affects signalling has not been sufficiently assessed. METHODOLOGY/PRINCIPAL FINDINGS: We studied changes in coloration after moult in four passerine birds (robin, Erithacus rubecula; blackbird, Turdus merula; blue tit, Cyanistes caeruleus; and great tit, Parus major displaying various coloration types (melanin-, carotenoid-based and structural. Birds were caught regularly during three years to measure plumage reflectance. We used models of avian colour vision to derive two variables, one describing chromatic and the other achromatic variation over the year that can be compared in magnitude among different colour types. All studied plumage patches but one (yellow breast of the blue tit showed significant chromatic changes over the year, although these were smaller than for a typical dynamic trait (bill colour. Overall, structural colours showed a reduction in relative reflectance at shorter wavelengths, carotenoid-based colours the opposite pattern, while no general pattern was found for melanin-based colours. Achromatic changes were also common, but there were no consistent patterns of change for the different types of colours. CONCLUSIONS/SIGNIFICANCE: Changes of plumage coloration independent of moult are probably widespread; they should be perceivable by birds and have the potential to affect colour signalling.

  15. [Costal cartilage structural and functional changes in children with a funnel or keeled chest].

    Science.gov (United States)

    Kurkov, A V; Shekhter, A B; Paukov, V S

    Congenital chest wall deformities (CCWDs) in children are severe diseases leading to cosmetic defects and diseases of the respiratory and cardiovascular systems. The most common of these deformities are funnel-shaped (pectus excavatum, FD) and keeled (pectus carinatum, KD) ones. The pathogenesis of CCWDs and the role of costal cartilage structural and functional changes in their pathogenesis have now been not well studied, which makes it difficult to elaborate pathogenetic approaches to correcting these diseases. Analysis of the literature has shown that structural and functional changes occur in the matrix and chondrocytes from the costal cartilage in FD. Similar costal cartilage changes are observed in KD. It is still unknown exactly which pathological processes are present in the costal cartilage and how they result in the development of one or other type of CCWDs. The role of amianthoid transformation (AT) of costal cartilages in these processes is also unknown. It is not improbable that it is AT drastically changing the native cartilage matrix, which is one of the key mechanisms leading to changes in its properties and to the subsequent development of FD or KD.

  16. Structural Changes Fundamental to Gating of the Cystic Fibrosis Transmembrane Conductance Regulator Anion Channel Pore.

    Science.gov (United States)

    Linsdell, Paul

    2017-01-01

    Cystic fibrosis is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR), an epithelial cell anion channel. Potentiator drugs used in the treatment of cystic fibrosis act on the channel to increase overall channel function, by increasing the stability of its open state and/or decreasing the stability of its closed state. The structure of the channel in either the open state or the closed state is not currently known. However, changes in the conformation of the protein as it transitions between these two states have been studied using functional investigation and molecular modeling techniques. This review summarizes our current understanding of the architecture of the transmembrane channel pore that controls the movement of chloride and other small anions, both in the open state and in the closed state. Evidence for different kinds of changes in the conformation of the pore as it transitions between open and closed states is described, as well as the mechanisms by which these conformational changes might be controlled to regulate normal channel gating. The ways that key conformational changes might be targeted by small compounds to influence overall CFTR activity are also discussed. Understanding the changes in pore structure that might be manipulated by such small compounds is key to the development of novel therapeutic strategies for the treatment of cystic fibrosis.

  17. Physiological and ultra-structural changes in tomato seedlings induced by lead

    OpenAIRE

    Moraes, Caroline Leivas; Marini, Patrícia; Fernando, Juliana Aparecida; Moraes, Dario Munt de; Castro, Luis Antônio Suita de; Lopes, Nei Fernandes

    2014-01-01

    The aim of this study was to verify the changes in seed viability, early growth, content of photosynthetic pigments and ultra-structural changes of Lycopersicon esculentum Mill seedlings caused by lead. Seeds were exposed to different concentrations of lead acetate (zero; 0.25; 0.5 and 0.75 mM). Percent germination and seedling emergence decreased as Pb concentration increased. In the same way, root length, dry mass and aerial parts also decreased as concentrations of Pb were increased, where...

  18. Parameters and structure of lunar regolith in Chang'E-3 landing area from lunar penetrating radar (LPR) data

    Science.gov (United States)

    Dong, Zehua; Fang, Guangyou; Ji, Yicai; Gao, Yunze; Wu, Chao; Zhang, Xiaojuan

    2017-01-01

    Chang'E-3 (CE-3) landed in the northwest Mare Imbrium, a region that has not been explored before. Yutu rover that released by CE-3 lander carried the first lunar surface penetrating radar (LPR) for exploring lunar regolith thickness and subsurface shallow geological structures. In this paper, based on the LPR data and the Panoramic Camera (PC) data, we first calculate the lunar surface regolith parameters in CE-3 landing area including its permittivity, density, conductivity and FeO + TiO2 content. LPR data provides a higher spatial resolution and more accuracy for the lunar regolith parameters comparing to other remote sensing techniques, such as orbit radar sounder and microwave sensing or earth-based powerful radar. We also derived the regolith thickness and its weathered rate with much better accuracy in the landing area. The results indicate that the regolith growth rate is much faster than previous estimation, the regolith parameters are not uniform even in such a small study area and the thickness and growth rate of lunar regolith here are different from other areas in Mare Imbrium. We infer that the main reason should be geological deformation that caused by multiple impacts of meteorites in different sizes.

  19. Assessing Metrics for Estimating Fire Induced Change in the Forest Understorey Structure Using Terrestrial Laser Scanning

    Directory of Open Access Journals (Sweden)

    Vaibhav Gupta

    2015-06-01

    Full Text Available Quantifying post-fire effects in a forested landscape is important to ascertain burn severity, ecosystem recovery and post-fire hazard assessments and mitigation planning. Reporting of such post-fire effects assumes significance in fire-prone countries such as USA, Australia, Spain, Greece and Portugal where prescribed burns are routinely carried out. This paper describes the use of Terrestrial Laser Scanning (TLS to estimate and map change in the forest understorey following a prescribed burn. Eighteen descriptive metrics are derived from bi-temporal TLS which are used to analyse and visualise change in a control and fire-altered plot. Metrics derived are Above Ground Height-based (AGH percentiles and heights, point count and mean intensity. Metrics such as AGH50change, mean AGHchange and point countchange are sensitive enough to detect subtle fire-induced change (28%–52% whilst observing little or no change in the control plot (0–4%. A qualitative examination with field measurements of the spatial distribution of burnt areas and percentage area burnt also show similar patterns. This study is novel in that it examines the behaviour of TLS metrics for estimating and mapping fire induced change in understorey structure in a single-scan mode with a minimal fixed reference system. Further, the TLS-derived metrics can be used to produce high resolution maps of change in the understorey landscape.

  20. Annual reversible plasticity of feeding structures: cyclical changes of jaw allometry in a sea urchin.

    Science.gov (United States)

    Ebert, Thomas A; Hernández, José Carlos; Clemente, Sabrina

    2014-03-22

    A wide variety of organisms show morphologically plastic responses to environmental stressors but in general these changes are not reversible. Though less common, reversible morphological structures are shown by a range of species in response to changes in predators, competitors or food. Theoretical analysis indicates that reversible plasticity increases fitness if organisms are long-lived relative to the frequency of changes in the stressor and morphological changes are rapid. Many sea urchin species show differences in the sizes of jaws (demi-pyramids) of the feeding apparatus, Aristotle's lantern, relative to overall body size, and these differences have been correlated with available food. The question addressed here is whether reversible changes of relative jaw size occur in the field as available food changes with season. Monthly samples of the North American Pacific coast sea urchin Strongylocentrotus purpuratus were collected from Gregory Point on the Oregon (USA) coast and showed an annual cycle of relative jaw size together with a linear trend from 2007 to 2009. Strongylocentrotus purpuratus is a long-lived species and under field conditions individuals experience multiple episodes of changes in food resources both seasonally and from year to year. Their rapid and reversible jaw plasticity fits well with theoretical expectations.

  1. Metal concentration and structural changes in Corallina elongata (Corallinales, Rhodophyta) from hydrothermal vents.

    Science.gov (United States)

    Couto, Ruben P; Neto, Ana I; Rodrigues, Armindo S

    2010-04-01

    Shallow-water hydrothermal activity is widely present at Azores archipelago. Organisms in such environments present great potential as sentinels of the effects derived from chronically exposure to increased temperature, metal concentrations and reduced pH. This study aimed to evaluate metal concentration in Corallina elongata collected at locations exposed and not exposed to shallow-water hydrothermal activity and evaluate changes in its calcareous structure. Elemental concentration was determined and morphometric analysis was performed by scanning electron microscopy. Thicker cell walls and a bleached appearance were observed on C. elongata specimens from the hydrothermally active location, as well as increased concentrations of elements associated to volcanic activity. This study reports on metal accumulation and morphometric changes in the calcareous structure of C. elongata from a hydrothermally active location, adding new data for further research on such habitats and communities, providing an insight on how coralline algae might be affected by ocean acidification. (c) 2009 Elsevier Ltd. All rights reserved.

  2. Structure constants of defect changing operators on the 1/2 BPS Wilson loop

    Science.gov (United States)

    Kim, Minkyoo; Kiryu, Naoki; Komatsu, Shota; Nishimura, Takuya

    2017-12-01

    We study three-point functions of operators on the 1/2 BPS Wilson loop in planar N = 4 super Yang-Mills theory. The operators we consider are "defect changing operators", which change the scalar coupled to the Wilson loop. We first perform the computation at two loops in general set-ups, and then study a special scaling limit called the ladders limit, in which the spectrum is known to be described by a quantum mechanics with the SL(2,R) symmetry. In this limit, we resum the Feynman diagrams using the Schwinger-Dyson equation and determine the structure constants at all order in the rescaled coupling constant. Besides providing an interesting solvable example of defect conformal field theories, our result gives invaluable data for the integrability-based approach to the structure constants.

  3. Metal concentration and structural changes in Corallina elongata (Corallinales, Rhodophyta) from hydrothermal vents

    International Nuclear Information System (INIS)

    Couto, Ruben P.; Neto, Ana I.; Rodrigues, Armindo S.

    2010-01-01

    Shallow-water hydrothermal activity is widely present at Azores archipelago. Organisms in such environments present great potential as sentinels of the effects derived from chronically exposure to increased temperature, metal concentrations and reduced pH. This study aimed to evaluate metal concentration in Corallina elongata collected at locations exposed and not exposed to shallow-water hydrothermal activity and evaluate changes in its calcareous structure. Elemental concentration was determined and morphometric analysis was performed by scanning electron microscopy. Thicker cell walls and a bleached appearance were observed on C. elongata specimens from the hydrothermally active location, as well as increased concentrations of elements associated to volcanic activity. This study reports on metal accumulation and morphometric changes in the calcareous structure of C. elongata from a hydrothermally active location, adding new data for further research on such habitats and communities, providing an insight on how coralline algae might be affected by ocean acidification.

  4. Variation of directional reflectance factors with structural changes of a developing alfalfa canopy

    Science.gov (United States)

    Kirchner, J. A.; Kimes, D. S.; Mcmurtrey, J. E., III

    1982-01-01

    Directional reflectance factors of an alfalfa canopy were determined and related to canopy structure, agronomic variables, and irradiance conditions at four periods during a cutting cycle. Nadir and off-nadir reflectance factors decreased with increasing biomass in Thematic Mapper band 3(0.63-0.69 micrometer) and increased with increasing biomass in band 4(0.76-0.90 micrometer). The sensor view angle had less impact on perceived reflectance as the alfalfa progressed from an erectophile canopy of stems after harvest to a near planophile canopy of leaves at maturity. Studies of directional reflectance are needed for testing and upgrading vegetation canopy models and to aid in the complex interpretation problems presented by aircraft scanners and pointable satellites where illumination and viewing geometries may vary widely. Distinct changes in the patterns of radiance observed by a sensor as structural and biomass changes occur are keys to monitoring the growth and condition of crops.

  5. Surface structural changes of naturally aged silicone and EPDM composite insulators

    Energy Technology Data Exchange (ETDEWEB)

    Vlastos, A.E. (Chalmers Univ. of Technology, S-412 96 Gothenburg (SE)); Gubanski, S.M. (Royal Inst. of Technology, S-100 44 Stockholm (SE))

    1991-04-01

    In a long-term outdoor test with high direct and alternating voltages, silicone and EPDM rubber composite insulators have, at the beginning, shown a superior performance to that of glass and porcelain insulators. In the long-term test, however, the silicone rubber composite insulator has, in spite of the ageing of both insulator types, kept its good performance, while the performance of the EPDM rubber composite insulator was drastically deteriorated. In order to get a better insight into results obtained, the wettability and the surface structural changes of the insulators were studied by the drop deposition method (using a goniometer) and by advanced techniques such as SEM, ESCA, FTIR and SIMS respectively. The results show that the differences in performance have to be found in the differences in the surface structural changes and in the dynamic ability of the surface to compensate the ageing.

  6. Changes of population by age and gender structure of Regions in the Republic of Macedonia

    Directory of Open Access Journals (Sweden)

    Resul Hamiti

    2015-07-01

    Full Text Available This paper analyzes the changes of population by age and the gender structure in the regions of the Republic of Macedonia. Age and gender is very important not only for the development of demographic process but also for the development of regions. They play an important role in planning the health care needs and other services with the socio-economic and cultural character. In this sense they affect the performance of demographic processes (births, deaths, marriages, etc. and are a result of bilateral relations fertility, mortality, migration movements and other social processes. The main objective of this paper is to identify the aging phenomenon of population in state level and regions. This paper also dedicates special importance to the changes of age and sex structure, during the period between1981-2014 in the regions of the republic of Macedonia.

  7. Probing Induced Structural Changes in Biomimetic Bacterial Cell Membrane Interactions with Divalent Cations

    Energy Technology Data Exchange (ETDEWEB)

    Holt, Allison M [ORNL; Standaert, Robert F [ORNL; Jubb, Aaron M [ORNL; Katsaras, John [ORNL; Johs, Alexander [ORNL

    2017-01-01

    Biological membranes, formed primarily by the self-assembly of complex mixtures of phospholipids, provide a structured scaffold for compartmentalization and structural processes in living cells. The specific physical properties of phospholipid species present in a given membrane play a key role in mediating these processes. Phosphatidylethanolamine (PE), a zwitterionic lipid present in bacterial, yeast, and mammalian cell membranes, is exceptional. In addition to undergoing the standard lipid polymorphic transition between the gel and liquid-crystalline phase, it can also assume an unusual polymorphic state, the inverse hexagonal phase (HII). Divalent cations are among the factors that drive the formation of the HII phase, wherein the lipid molecules form stacked tubular structures by burying the hydrophilic head groups and exposing the hydrophobic tails to the bulk solvent. Most biological membranes contain a lipid species capable of forming the HII state suggesting that such lipid polymorphic structural states play an important role in structural biological processes such as membrane fusion. In this study, the interactions between Mg2+ and biomimetic bacterial cell membranes composed of PE and phosphatidylglycerol (PG) were probed using differential scanning calorimetry (DSC), small-angle x-ray scattering (SAXS), and fluorescence spectroscopy. The lipid phase transitions were examined at varying ratios of PE to PG and upon exposure to physiologically relevant concentrations of Mg2+. An understanding of these basic interactions enhances our understanding of membrane dynamics and how membrane-mediated structural changes may occur in vivo.

  8. Transient Structures and Possible Limits of Data Recording in Phase-Change Materials.

    Science.gov (United States)

    Hu, Jianbo; Vanacore, Giovanni M; Yang, Zhe; Miao, Xiangshui; Zewail, Ahmed H

    2015-07-28

    Phase-change materials (PCMs) represent the leading candidates for universal data storage devices, which exploit the large difference in the physical properties of their transitional lattice structures. On a nanoscale, it is fundamental to determine their performance, which is ultimately controlled by the speed limit of transformation among the different structures involved. Here, we report observation with atomic-scale resolution of transient structures of nanofilms of crystalline germanium telluride, a prototypical PCM, using ultrafast electron crystallography. A nonthermal transformation from the initial rhombohedral phase to the cubic structure was found to occur in 12 ps. On a much longer time scale, hundreds of picoseconds, equilibrium heating of the nanofilm is reached, driving the system toward amorphization, provided that high excitation energy is invoked. These results elucidate the elementary steps defining the structural pathway in the transformation of crystalline-to-amorphous phase transitions and describe the essential atomic motions involved when driven by an ultrafast excitation. The establishment of the time scales of the different transient structures, as reported here, permits determination of the possible limit of performance, which is crucial for high-speed recording applications of PCMs.

  9. VA Health Care: Processes to Evaluate, Implement, and Monitor Organizational Structure Changes Needed

    Science.gov (United States)

    2016-09-01

    Human Resource Administration . 30VHA held a strategic planning summit in April 2016. One of the objectives of the summit was to make decisions to guide...before the realignment started, but according to senior task force officials, the task force did not establish a subgroup on human resources until...Monitor Organizational Structure Changes Needed What GAO Found Recent internal and external reviews of Veterans Health Administration (VHA

  10. A Model of Target Changes and the Term Structure of Interest Rates

    OpenAIRE

    Pierluigi Balduzzi; Giuseppe Bertola; Silverio Foresi

    1993-01-01

    We explore the effects of official targeting policy on the term-structure of nominal interest rates, adapting relevant insights from theoretical work on "peso problems" to account for realistic infrequency of target changes. Our analysis of daily U.S. interest rates and newly available historical targets provides an interpretation for persistent spreads between short-term money-market rates and overnight fed-funds targets, and for the poor performance of expectations-hypothesis tests: it is t...

  11. Population Policies, Demographic Structural Changes, and the Chinese Household Saving Puzzle

    OpenAIRE

    Ge, Suqin; Yang, Dennis T.; Zhang, Junsen

    2012-01-01

    Using combined data from population censuses and Urban Household Surveys, we study the effects of demographic structural changes on the rise in household saving in China. Variations in fines across provinces on unauthorized births under the one-child policy and in cohort-specific fertility influenced by the implementation of population control policies are exploited to facilitate identification. We find evidence that older households with a reduced number of adult children save more because o...

  12. Transformational leadership and change readiness and a moderating role of perceived bureaucratic structure: an empirical investigation

    OpenAIRE

    Badri Abbasi

    2017-01-01

    The purpose of this study was to examine the relationship between transformational leadership and change readiness through perceived bureaucratic structure among government employees in Rasht. As a methodology, descriptive method was applied using questionnaire to collect data. The studied population consisted of 600 employees from three state organizations including Municipality, Gilan Tax Department and Gilan Justice Court. According to Morgan table, the sample size was estimated at 234. Th...

  13. Portfolio Sensitivity Model for Analyzing Credit Risk Caused by Structural and Macroeconomic Changes

    Directory of Open Access Journals (Sweden)

    Goran Klepac

    2008-12-01

    Full Text Available This paper proposes a new model for portfolio sensitivity analysis. The model is suitable for decision support in financial institutions, specifically for portfolio planning and portfolio management. The basic advantage of the model is the ability to create simulations for credit risk predictions in cases when we virtually change portfolio structure and/or macroeconomic factors. The model takes a holistic approach to portfolio management consolidating all organizational segments in the process such as marketing, retail and risk.

  14. Localization of the places of stress-strain state changes of building structures based on the vibrodiagnostic measurement data

    Directory of Open Access Journals (Sweden)

    Shakhraman'yan Andrey Mikhaylovich

    Full Text Available The method of localization of changes in the deflected mode is based on the analysis of time series of oscillations (displacement, velocity, acceleration of building constructions and structures. The method is based on the hypothesis that any changes in the deflected mode of structures result in changes in the oscillation energy. In this case, once the information on the structure oscillation parameters in different points of the building is available, the changes in the oscillation energy will signify the changes in the deflected mode in the relevant points.

  15. Age-related changes in grey and white matter structure throughout adulthood.

    Science.gov (United States)

    Giorgio, Antonio; Santelli, Luca; Tomassini, Valentina; Bosnell, Rose; Smith, Steve; De Stefano, Nicola; Johansen-Berg, Heidi

    2010-07-01

    Normal ageing is associated with gradual brain atrophy. Determining spatial and temporal patterns of change can help shed light on underlying mechanisms. Neuroimaging provides various measures of brain structure that can be used to assess such age-related change but studies to date have typically considered single imaging measures. Although there is consensus on the notion that brain structure deteriorates with age, evidence on the precise time course and spatial distribution of changes is mixed. We assessed grey matter (GM) and white matter (WM) structure in a group of 66 adults aged between 23 and 81. Multimodal imaging measures included voxel-based morphometry (VBM)-style analysis of GM and WM volume and diffusion tensor imaging (DTI) metrics of WM microstructure. We found widespread reductions in GM volume from middle age onwards but earlier reductions in GM were detected in frontal cortex. Widespread age-related deterioration in WM microstructure was detected from young adulthood onwards. WM decline was detected earlier and more sensitively using DTI-based measures of microstructure than using markers of WM volume derived from conventional T1-weighted imaging. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  16. Strain-induced structural changes and chemical reactions. 1: Thermomechanical and kinetic models

    International Nuclear Information System (INIS)

    Levitas, V.I.; Nesterenko, V.F.; Meyers, M.A.

    1998-01-01

    Strain-induced chemical reactions were observed recently (Nesterenko et al) in experiments in the shear band in both Ti-Si and Nb-Si mixtures. Reactions can start in the solid state or after melting of at least one component. One of the aims is to find theoretically whether there are possible macroscopic mechanisms of mechanical intensification of the above and other chemical reactions due to plastic shear in the solid state. Continuum thermodynamical theory of structural changes with an athermal kinetics, which includes martensitic phase transformations, plastic strain-induced chemical reactions and polymorphic transformations, is developed at finite strains. The theory includes kinematics, criterion of structural change and extremum principle for determination of all unknown variable parameters for the case with neglected elastic strains. Thermodynamically consistent kinetic theory of thermally activated structural changes is suggested. The concept of the effective temperature is introduced which takes into account that temperature can vary significantly (on 1,000 K) during the chemical reactions under consideration. The theory will be applied in Part 2 of the paper for the description of chemical reactions in the shear band

  17. Research on change of surface structure of organic materials by Kr+ irradiation

    International Nuclear Information System (INIS)

    Nakase, Yoshiaki

    1990-01-01

    When ionized atoms or molecules are irradiated to materials, the irradiation effect based on the release of the energy that the ions possess and the effect due to the introduction of the atoms or molecules must be considered. These can be confirmed as the structural change, the change in molecular arrangement and crystalline structure, originated in the severance and cross-link of the molecules composing material, and as the structural change of higher order originated in the movement and recoil of the atoms or molecules of base materials accompanying the introduction of the atoms or molecules. It has been known that by the ion irradiation to polymer films, the film surfaces are easily colored. In order to examine the range and dose of ion irradiation, polyethylene telephthalate (PET), cellulose triacetate (CTA) and polyimide were irradiated with Kr + having medium energy of 35 keV. As for the irradiated samples, the measurement of light absorption and the general surface analysis were carried out. In the case of ion irradiation, light absorption increases due to substantial coloring. The experiment and the results are reported. (K.I.)

  18. Structural changes in the Czech, Slovak and euro area economies during the Great Recession

    Directory of Open Access Journals (Sweden)

    Tvrz Stanislav

    2016-12-01

    Full Text Available The goal of this paper is to identify and compare the most important changes in the structure of the Czech economy, as a small open economy with independent monetary policy, the Slovak economy, as a small open economy that entered monetary union, and the economy of the euro area, which has a common monetary policy, during the turbulent period of the Great Recession, the subsequent anaemic recovery and recent disinflationary period. Structural changes are identified with the help of nonlinear dynamic stochastic models of general equilibrium with time-varying parameters. The model parameters are estimated using Bayesian methods and a nonlinear particle filter. The results confirm the similarity of the Czech and Slovak economies and show that in certain respects the structure of the Czech economy might be closer to that of the euro area than that of Slovakia. The time-varying estimates reveal many similarities between the parameter changes in the Czech economy and those in the euro area. In Slovakia, the situation during the Great Recession was dominated by the country’s adoption of the euro, which caused large deviations in its Calvo parameters.

  19. Childhood Music Training Induces Change in Micro and Macroscopic Brain Structure: Results from a Longitudinal Study.

    Science.gov (United States)

    Habibi, Assal; Damasio, Antonio; Ilari, Beatriz; Veiga, Ryan; Joshi, Anand A; Leahy, Richard M; Haldar, Justin P; Varadarajan, Divya; Bhushan, Chitresh; Damasio, Hanna

    2017-11-08

    Several studies comparing adult musicians and nonmusicians have shown that music training is associated with structural brain differences. It is not been established, however, whether such differences result from pre-existing biological traits, lengthy musical training, or an interaction of the two factors, or if comparable changes can be found in children undergoing music training. As part of an ongoing longitudinal study, we investigated the effects of music training on the developmental trajectory of children's brain structure, over two years, beginning at age 6. We compared these children with children of the same socio-economic background but either involved in sports training or not involved in any systematic after school training. We established at the onset that there were no pre-existing structural differences among the groups. Two years later we observed that children in the music group showed (1) a different rate of cortical thickness maturation between the right and left posterior superior temporal gyrus, and (2) higher fractional anisotropy in the corpus callosum, specifically in the crossing pathways connecting superior frontal, sensory, and motor segments. We conclude that music training induces macro and microstructural brain changes in school-age children, and that those changes are not attributable to pre-existing biological traits. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. A nonstoichiometric structural model to characterize changes in the nickel hydroxide electrode during cycling

    International Nuclear Information System (INIS)

    Srinivasan, Venkat; Bahne, C. Cornilsen; Weidner, John W.

    2003-01-01

    Experimental capacities and mass changes are recorded using an electrochemical quartz crystal microbalance during the first 9 charge and discharge cycles of nickel hydroxide thin films cycled in 3.0 weight percent (wt%) potassium hydroxide electrolyte. For the first time, the film capacities have been corrected for the oxygen evolution side reaction, and the data used as input into the point defect-containing structural model to track the changes that occur during short-term cycling. Variations in capacity and mass during formation and charge/discharge cycling are related to changes in the point defect parameters, thus providing a structural origin for the unique experimental variations observed here and often reported in the literature, but previously unexplained. Proton-, potassium-, and water-content vary in the active material during charge/discharge cycling. The observed capacity loss, or ''capacity fade'', is explained by incomplete incorporation of potassium ions in (or near) the nickel vacancy during charge, as additional protons are then allowed to occupy the vacant lattice site. The increase in water content during reduction parallels the expansion of the electrode that is well known during cycling. This result confirms the origin of the swelling phenomenon as being caused by water incorporation. The model and methodology developed in this paper can be used to correlate electrochemical signatures with material chemical structure

  1. Structural changes of low density lipoproteins with Cu2+ and glucose induced oxidation.

    Science.gov (United States)

    Gallego-Nicasio, J; López-Rodríguez, G; Martínez, R; Tarancón, M J; Fraile, M V; Carmona, P

    2003-01-01

    The compositional and structural changes of lipids and apolipoproteins during in vitro oxidation of low density lipoprotein (LDL) are investigated in this study by IR spectroscopy. For comparison, LDL samples containing either copper or glucose at physiological or pathological concentrations are considered in order to know the separate affects of these chemical factors on LDL oxidation. The results show that the initial steps of lipid oxidation proceed through hydrogen atom loss from methylene groups, as well as loss of cholesteryl ester molecules, and later a recovering of carbonyl compounds resulting from aldehyde formation that generally occurs in autooxidation processes. Lipid oxidation is induced by copper ions, and glucose enhances metal ion induced LDL oxidation as determined by conjugated diene formation. As to the protein conformational changes, IR spectroscopy reveals for the first time that LDL oxidation involves formation of beta-sheet structures, these being more abundant in LDL samples with pathological concentrations of glucose or copper. Consequently, the LDL structural changes may contribute to the recognition of oxidized LDL particles by scavenger receptors. Copyright 2003 Wiley Periodicals, Inc.

  2. A DSC investigation on the changes in pore structure of skin during leather processing

    International Nuclear Information System (INIS)

    Fathima, N. Nishad; Kumar, M. Pradeep; Rao, J. Raghava; Nair, B.U.

    2010-01-01

    Leather processing involves many unit operations that modify the physical, chemical and biological properties of the raw skin/hide of an animal. One such major variation is brought to pore structure and size, which determines the breathing property of skin. Understanding this property is essential to improve the end use of the leather matrix. Thermoporometric technique has been used in this study to bring out the influence of various process steps on the pore size distribution of skin. Marked changes in the depression of freezing point are observed for each process. Scanning electron microscopy study reveals the morphological changes in the grain and cross-section of the skin during leather processing. Understanding and predictions of pore structure changes at various stages of leather processing would benefit: (a) in process control, (b) analysis of cost benefit ratio and (c) strategic planning and transport. Thus, this study aids in better understanding of the pore structure of skin to improve the functional properties of the leather.

  3. Texture analysis for the assessment of structural changes in parotid glands induced by radiotherapy

    International Nuclear Information System (INIS)

    Scalco, Elisa; Fiorino, Claudio; Cattaneo, Giovanni Mauro; Sanguineti, Giuseppe; Rizzo, Giovanna

    2013-01-01

    Background and purpose: During radiotherapy (RT) for head-and-neck cancer, parotid glands undergo significant anatomic, functional and structural changes which could characterize pre-clinical signs of an increased risk of xerostomia. Texture analysis is proposed to assess structural changes of parotids induced by RT, and to investigate whether early variations of textural parameters (such as mean intensity and fractal dimension) can predict parotid shrinkage at the end of treatment. Material and methods: Textural parameters and volumes of 42 parotids from 21 patients treated with intensity-modulated RT for nasopharyngeal cancer were extracted from CT images. To individuate which parameters changed during RT, a Wilcoxon signed-rank test between textural indices (first and second RT week; first and last RT week) was performed. Discriminant analysis was applied to variations of these parameters in the first two weeks of RT to assess their power in predicting parotid shrinkage at the end of RT. Results: A significant decrease in mean intensity (1.7 HU and 3.8 HU after the second and last weeks, respectively) and fractal dimension (0.016 and 0.021) was found. Discriminant analysis, based on volume and fractal dimension, was able to predict the final parotid shrinkage (accuracy of 71.4%). Conclusion: Textural features could be used in combination with volume to characterize structural modifications on parotid glands and to predict parotid shrinkage at the end of RT

  4. Infrared spectroscopy study of structural changes in glass-forming salol.

    Science.gov (United States)

    Baran, J; Davydova, N A

    2010-03-01

    We report the investigation of glass-forming salol upon different courses of the temperature changes from liquid to glass state and back using FT-IR spectroscopy measurements in the wide spectral and temperature ranges. The formation of the ordered clusters in supercooled liquid salol has been observed at 250 K. When the temperature is decreased further to 11 K these ordered clusters become an element of the glass structure. With increasing temperature to 270 K through the glass transition noticeable evolutions of the IR spectrum occurs up till the ordered clusters are developed into crystal. So produced crystal melts in the temperature range 300-310 K, that corresponds to the melting temperature of the metastable phase (Tmelt=302 K) . Thus, the crystalline structure of the ordered clusters corresponds to the structure of metastable phase and is monoclinic.

  5. ADAPTIVE GOP STRUCTURE TO H.264/AVC BASED ON SCENE CHANGE

    Directory of Open Access Journals (Sweden)

    S. Sowmyayani

    2014-08-01

    Full Text Available This paper proposes an adaptive GOP structure with the new logic of frame comparison in H.264/AVC to achieve better quality and reduce bit rate. Initially Group of Pictures (GOP is set to a fixed size. Frames are compared within that GOP using correlation. According to the correlation, GOP is changed within that fixed size. So, there will be no GOP size greater than that fixed size. This method does not calculate any threshold. Hence the time needed to calculate global or local threshold is eliminated. It is integrated with conventional video codec H.264/AVC. This method is compared with H.264/AVC of fixed GOP structure of sizes 4, 8, 12, 16, 32 and GOP structure with the length of entire video. The proposed method achieved gain in bit rate from 0.49% to 69.75% and PSNR gain from 2.5% to 0.3%.

  6. How Cr changes the dislocation core structure of α-Fe: the role of magnetism.

    Science.gov (United States)

    Zhang, Xu; Lu, Gang

    2013-02-27

    Cr is a critical alloying element in ferritic steels and its effect on the dislocation core structure of α-Fe is examined computationally using a quantum mechanics/molecular mechanics method. We find that Cr can significantly change the dislocation core structure of Fe where magnetism plays a crucial role. The strain-dependent magnetic interaction between Cr and the host Fe atoms is responsible for the dislocation core structure. When Cr is at the tension side of the slip plane, the Cr-Fe magnetic interaction is repulsive, which lowers the dislocation energy and pins the dislocation. When Cr occupies the compression side of the slip plane, the Cr-Fe interaction is attractive which increases the dislocation energy and promotes the dislocation to break away from Cr.

  7. Changes of optical, dielectric, and structural properties of Si15Sb85 phase change memory thin films under different initializing laser power

    International Nuclear Information System (INIS)

    Huang Huan; Zhang Lei; Wang Yang; Han Xiaodong; Wu Yiqun; Zhang Ze; Gan Fuxi

    2011-01-01

    Research highlights: → We study the optical, dielectric, and structural characteristics of Si 15 Sb 85 phase change memory thin films under a moving continuous-wave laser initialization. → The optical and dielectric constants, absorption coefficient of Si 15 Sb 85 change regularly with the increasing laser power. → The optical band gaps of Si 15 Sb 85 irradiated upon different power lasers were calculated. → HRTEM images of the samples were observed and the changes of optical and dielectric constants are determined by crystalline structures changes of the films. - Abstract: The optical, dielectric, and structural characteristics of Si 15 Sb 85 phase change memory thin films under a moving continuous-wave laser initialization are studied by using spectroscopic ellipsometry and high-resolution transmission electron microscopy. The dependence of complex refractive index, dielectric functions, absorption coefficient, and optical band gap of the films on its crystallization extents formed by the different initialization laser power are analyzed in detail. The structural change from as-deposited amorphous phase to distorted rhombohedra-Sb-like crystalline structure with the increase of initialization laser power is clearly observed with sub-nanometer resolution. The optical and dielectric constants, the relationship between them, and the local atomic arrangements of this new phase change material can help explain the phase change mechanism and design the practical phase change memory devices.

  8. Single Nanostructure Electrochemical Devices for Studying Electronic Properties and Structural Changes in Lithiated Si Nanowires

    KAUST Repository

    McDowell, Matthew T.

    2011-07-19

    Nanostructured Si is a promising anode material for the next generation of Li-ion batteries, but few studies have focused on the electrical properties of the Li-Si alloy phase, which are important for determining power capabilities and ensuring sufficient electrical conduction in the electrode structure. Here, we demonstrate an electrochemical device framework suitable for testing the electrical properties of single Si nanowires (NWs) at different lithiation states and correlating these properties with structural changes via transmission electron microscopy (TEM). We fi nd that single Si NWs usually exhibit Ohmic I - V response in the lithiated state, with conductivities two to three orders of magnitude higher than in the delithiated state. After a number of sequential lithiation/delithiation cycles, the single NWs show similar conductivity after each lithiation step but show large variations in conductivity in the delithiated state. Finally, devices with groups of NWs in physical contact were fabricated, and structural changes in the NWs were observed after lithiation to investigate how the electrical resistance of NW junctions and the NWs themselves affect the lithiation behavior. The results suggest that electrical resistance of NW junctions can limit lithiation. Overall, this study shows the importance of investigating the electronic properties of individual components of a battery electrode (single nanostructures in this case) along with studying the nature of interactions within a collection of these component structures. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Change and recovery of coastal mesozooplankton community structure during the Deepwater Horizon oil spill

    Science.gov (United States)

    Carassou, L.; Hernandez, F. J.; Graham, W. M.

    2014-12-01

    The response of mesozooplankton community structure to the Deepwater Horizon oil spill in the northern Gulf of Mexico was investigated using data from a long-term plankton survey off the coast of Alabama (USA). Environmental conditions observed in the study area during the oil spill (2010) were compared to historical observations (2005-2009), to support the contention that variations observed in zooplankton assemblage structure may be attributed to the oil spill, as opposed to natural climatic or environmental variations. Zooplankton assemblage structure observed during the oil spill period (May-August) in 2010 was then compared to historical observations from the same period (2005-2009). Significant variations were detected in assemblage structure in May and June 2010, but these changes were no longer significant by July 2010. The density of ostracods, cladocerans and echinoderm larvae were responsible for most of the differences observed, but patterns differed depending on taxa and months. Many taxa had higher densities during the oil spill year, including calanoid and cyclopoid copepods, ostracods, bivalve larvae and cladocerans, among others. Although this result is somewhat surprising, it is possible that increased microbial activity related to the infusion of oil carbon may have stimulated secondary production through microbial-zooplankton trophic linkages. Overall, results suggest that, although changes in zooplankton community composition were observed during the oil spill, variations were weak and recovery was rapid.

  10. Modeling High Frequency Data with Long Memory and Structural Change: A-HYEGARCH Model

    Directory of Open Access Journals (Sweden)

    Yanlin Shi

    2018-03-01

    Full Text Available In this paper, we propose an Adaptive Hyperbolic EGARCH (A-HYEGARCH model to estimate the long memory of high frequency time series with potential structural breaks. Based on the original HYGARCH model, we use the logarithm transformation to ensure the positivity of conditional variance. The structural change is further allowed via a flexible time-dependent intercept in the conditional variance equation. To demonstrate its effectiveness, we perform a range of Monte Carlo studies considering various data generating processes with and without structural changes. Empirical testing of the A-HYEGARCH model is also conducted using high frequency returns of S&P 500, FTSE 100, ASX 200 and Nikkei 225. Our simulation and empirical evidence demonstrate that the proposed A-HYEGARCH model outperforms various competing specifications and can effectively control for structural breaks. Therefore, our model may provide more reliable estimates of long memory and could be a widely useful tool for modelling financial volatility in other contexts.

  11. Structural changes in collagen fibrils across a mineralized interface revealed by cryo-TEM.

    Science.gov (United States)

    Quan, Bryan D; Sone, Eli D

    2015-08-01

    The structure of the mineralized collagen fibril, which is the basic building block of mineralized connective tissues, is critical to its function. We use cryo-TEM to study collagen structure at a well-defined hard-soft tissue interface, across which collagen fibrils are continuous, in order to evaluate changes to collagen upon mineralization. To establish a basis for the analysis of collagen banding, we compared cryo-TEM images of rat-tail tendon collagen to a model based on the X-ray structure. While there is close correspondence of periodicity, differences in band intensity indicate fibril regions with high density but lacking order, providing new insight into collagen fibrillar structure. Across a mineralized interface, we show that mineralization results in an axial contraction of the fibril, concomitant with lateral expansion, and that this contraction occurs only in the more flexible gap region of the fibril. Nevertheless, the major features of the banding pattern are not significantly changed, indicating that the axial arrangement of molecules remains largely intact. These results suggest a mechanism by which collagen fibrils are able to accommodate large amounts of mineral without significant disruption of their molecular packing, leading to synergy of mechanical properties. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Quantification of structural changes in acute inflammation by fractal dimension, angular second moment and correlation.

    Science.gov (United States)

    Stankovic, Marija; Pantic, Igor; De Luka, Silvio R; Puskas, Nela; Zaletel, Ivan; Milutinovic-Smiljanic, Sanja; Pantic, Senka; Trbovich, Alexander M

    2016-03-01

    The aim of the study was to examine alteration and possible application of fractal dimension, angular second moment, and correlation for quantification of structural changes in acutely inflamed tissue. Acute inflammation was induced by injection of turpentine oil into the right and left hind limb muscles of mice, whereas control animals received intramuscular saline injection. After 12 h, animals were anesthetised and treated muscles collected. The tissue was stained by hematoxylin and eosin, digital micrographs produced, enabling determination of fractal dimension of the cells, angular second moment and correlation of studied tissue. Histopathological analysis showed presence of inflammatory infiltrate and tissue damage in inflammatory group, whereas tissue structure in control group was preserved, devoid of inflammatory infiltrate. Fractal dimension of the cells, angular second moment and correlation of treated tissue in inflammatory group decreased in comparison to the control group. In this study, we were first to observe and report that fractal dimension of the cells, angular second moment, and correlation were reduced in acutely inflamed tissue, indicating loss of overall complexity of the cells in the tissue, the tissue uniformity and structure regularity. Fractal dimension, angular second moment and correlation could be useful methods for quantification of structural changes in acute inflammation. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

  13. Changes in residential, occupational and gender structure of the greater Bangkok in the globalization process

    Directory of Open Access Journals (Sweden)

    Satoshi Nakagawa

    2004-12-01

    Full Text Available This study investigated recent changes in migration and population structure of the Greater Bangkok considering the impact of economic globalization. The spatial policy of the Thai government has lead newer investments for manufacturing to locate away from Bangkok Metropolis and thereby the industrial structure of Bangkok Metropolis has gradually turned into service-dominated, while the region surrounding Bangkok Metropolis has attracted factories mainly owned by foreign capital. Light industry and electronics industry are con-centrated in the adjacent provinces to Bangkok Metropolis and the heavy and petrochemical industry tends to be located in the outer zone of the surrounding region. The service sector and light industry as well as electronics industry prefer female workers and Bangkok met-ropolis and the adjoining provinces have become female-dominated population structure while male workers tend to gather in the outer zone attracted by heavy and petrochemical industry. It is possible to mention accordingly that the unbalanced spatial distribution of sex structure of population which might cause changes in the norm to the family formation in future is one of the consequences of economic globalization of Thailand, which the inves-tment promotion policy of the government did not assume.

  14. Electronic Structure Changes Due to Crystal Phase Switching at the Atomic Scale Limit.

    Science.gov (United States)

    Knutsson, Johan Valentin; Lehmann, Sebastian; Hjort, Martin; Lundgren, Edvin; Dick, Kimberly A; Timm, Rainer; Mikkelsen, Anders

    2017-10-24

    The perfect switching between crystal phases with different electronic structure in III-V nanowires allows for the design of superstructures with quantum wells only a single atomic layer wide. However, it has only been indirectly inferred how the electronic structure will vary down to the smallest possible crystal segments. We use low-temperature scanning tunneling microscopy and spectroscopy to directly probe the electronic structure of Zinc blende (Zb) segments in Wurtzite (Wz) InAs nanowires with atomic-scale precision. We find that the major features in the band structure change abruptly down to a single atomic layer level. Distinct Zb electronic structure signatures are observed on both the conduction and valence band sides for the smallest possible Zb segment: a single InAs bilayer. We find evidence of confined states in the region of both single and double bilayer Zb segments indicative of the formation of crystal segment quantum wells due to the smaller band gap of Zb as compared to Wz. In contrast to the internal electronic structure of the nanowire, surface states located in the band gap were found to be only weakly influenced by the presence of the smallest Zb segments. Our findings directly demonstrate the feasibility of crystal phase switching for the ultimate limit of atomistic band structure engineering of quantum confined structures. Further, it indicates that band gap values obtained for the bulk are reasonable to use even for the smallest crystal segments. However, we also find that the suppression of surface and interface states could be necessary in the use of this effect for engineering of future electronic devices.

  15. The self-concept and conjugal loss: evidence for structural change.

    Science.gov (United States)

    Montpetit, Mignon A; Bergeman, C S; Bisconti, Toni L

    2010-08-01

    The self-concept is often considered to be a personal resource that individuals may use to cope with life stressors, but little is known about how this entity might itself change in response to profound stress. The present study examines structural change in self-concept following conjugal loss in later life. Analyses were conducted on data collected from 57 widows every 4 months over the first 2 years post-loss. The first objective was to explore the adequacy of an operational definition of the self-concept as a latent construct lying at the confluence of self-esteem, perceived environmental mastery, and optimism. Because confirmatory factor analysis (CFA) supported this theoretically based conceptualization, the second objective of the study was to model stability and change in the structure of the self-concept over the 2-year study period. Results suggested that there is both stability and change in the self-system during the adjustment to major life stress.

  16. Roads and associated structures: infrastructure impacts, vulnerabilities and design considerations for future climate change

    International Nuclear Information System (INIS)

    Tighe, S.L.; Lapp, D.

    2009-01-01

    This paper provides a summary of the findings from the literature scan, directed at identifying engineering literature that relates to road and associated infrastructure vulnerabilities in light of climate change. The scan was carried out over the course of several weeks in late 2007/early 2008. Although many Canadian transportation agencies are thinking about the potential vulnerabilities and associated engineering impacts, very few agencies have completed any formal analysis at this time. A few agencies currently have some on-going activities that are expected to be completed in 2008, but the majority have not started to examine the engineering aspects of how the change will need to be addressed in design, construction and maintenance. Although climate change and it's impact on transportation and specifically roads and associated structures is appearing in various reports and documents across Canada, available detailed information on engineering impacts was limited to nonexistent. This paper includes a brief introduction and background on climate change in general and the related predicted impacts on road infrastructure and associated structures, with primary focus on bridges. These sections are followed by project scope and objectives and methodology of assessment. The summary of findings provides some more specific details and has been prepared using available public agency documents that were located during the aforementioned search. Finally a few closing comments are provided. (author)

  17. Coping with change: Household structure and composition in rural South Africa, 1992 – 20031

    Science.gov (United States)

    MADHAVAN, SANGEETHA; SCHATZ, ENID J.

    2010-01-01

    Aim To describe household change over a 10-year period of tremendous social, political, economic and health transformation in South Africa using data from the Agincourt health and demographic surveillance system in the rural northeast of South Africa. Methods Examination of household structure and composition at three points: 1992, 1997, and 2003. These three years loosely represent conditions immediately before the elections (1992), short term post-elections (1997), and longer term (2003), and span a period of notable increase in HIV prevalence. Results Average household size decreased and the proportion headed by females increased. The within-household dependency ratios for children and elders both decreased, as did the proportion of households containing foster children. The proportion with at least one maternal orphan doubled, but was still relatively small at 5.5%. Conclusions This analysis is a starting point for future investigations aimed at explaining how HIV/AIDS and other sociocultural changes post-apartheid have impacted on household organization. The analysis shows both consistency and change in measures of household structure and composition between 1992 and 2003. The changes do not include an increase in various types of “fragile families”, such as child-headed or skipped-generation households that might be expected due to HIV/AIDS. PMID:17676508

  18. How do changes in plankton community structure influence the biological pump? A mesocosm study

    Science.gov (United States)

    Stange, P.; Taucher, J.; Bach, L. T.; Boxhammer, T.; Riebesell, U.

    2016-02-01

    Strength and efficiency of the biological pump have a profound influence on the marine carbon cycle and depend on the plankton community structure of the ocean. Unraveling this control will significantly increase our understanding of the biological pump and help predicting changes in the future. However, investigating this relationship with traditional methods is challenging in the open ocean. During autumn 2014, we conducted a mesocosm experiment off the coast of the Canary Islands (CE Atlantic). We closely followed the development of a plankton community under different CO2 levels for eight weeks, while simultaneously measuring the mass flux, sinking velocity and remineralization rates of sinking detritus. After two weeks of low productivity we added deep-water (collected from 500 m depth) to each mesocosm to mimic eddy-induced upwelling. The addition induced a diatom bloom, characterized by an increased abundance of large particles and high mass flux. However, sinking velocities decreased by up to 30% and remineralization rates remained rather constant, indicating that higher mass flux is associated with lower export efficiency during the bloom. Our first results highlight the importance of community-related changes on both export strength and efficiency of the biological pump. We show that high mass flux events are potentially less efficient in sequestering carbon from the atmosphere. Ultimately, changes in plankton community structure have the potential to significantly affect oceanic carbon sequestration in a changing environment.

  19. Mammographic density measured as changes in tissue structure caused by HRT

    Science.gov (United States)

    Raundahl, Jakob; Loog, Marco; Nielsen, Mads

    2006-03-01

    Numerous studies have investigated the relation between mammographic density and breast cancer risk. These studies indicate that women with high breast density have a four to six fold risk increase. An investigation of whether or not this relation is causal is important for, e.g., hormone replacement therapy (HRT), which has been shown to actually increase the density. No gold standard for automatic assessment of mammographic density exists. Manual methods such as Wolfe patterns and BI-RADS are helpful for communication of diagnostic sensitivity, but they are both time consuming and crude. They may be sufficient in certain cases and for single measurements, but for serial, temporal analysis it is necessary to be able to detect more subtle changes and, in addition, to be more reproducible. In this work an automated method for measuring the effect of HRT w.r.t. changes in biological density in the breast is presented. This measure is a novel measure, which provides structural information orthogonal to intensity-based methods. Hessian eigenvalues at different scales are used as features and a clustering of these is employed to divide a mammogram into four structurally different areas. Subsequently, based on the relative size of the areas, a density score is determined. In the experiments, two sets of mammograms of 50 patients from a double blind, placebo controlled HRT experiment were used. The change in density for the HRT group, measured with the new method, was significantly higher (p = 0.0002) than the change in the control group.

  20. Risk factors associated with structural postural changes in the spinal column of children and adolescents

    Directory of Open Access Journals (Sweden)

    Juliana Adami Sedrez

    2015-03-01

    Full Text Available OBJECTIVE: To investigate the association between behavioral risk factors, specifically postural habits, with the presence of structural changes in the spinal column of children and adolescents. METHODS: 59 students were evaluated through the self-reporting Back Pain and Body Posture Evaluation Instrument and spinal panoramic radiographic examination. Spine curvatures were classified based on Cobb angles, as normal or altered in the saggital plane and as normal or scoliotic in the frontal plane. Data were analyzed using SPSS 18.0, based on descriptive statistics and chi-square association test (a=0,05. RESULTS: The prevalence of postural changes was 79.7% (n=47, of which 47.5% (n=28 showed frontal plane changes and 61% (n=36 sagital plane changes. Significant association was found between the presence of thoracic kyphosis and female gender, practice of physical exercises only once or twice a week, sleep time greater than 10 hours, inadequate postures when sitting on a seat and sitting down to write, and how school supplies are carried. Lumbar lordosis was associated with the inadequate way of carrying the school backpack (asymmetric; and scoliosis was associated wuth the practice of competitive sports and sleep time greater than 10 hours. CONCLUSIONS: Lifestyle may be associated with postural changes. It is important to develop health policies in order to reduce the prevalence of postural changes, by decreasing the associated risk factors.

  1. Modelling a sector undergoing structural change: The case of Danish energy supply

    DEFF Research Database (Denmark)

    Klinge Jacobsen, Henrik

    2000-01-01

    for the demand of the produced goods. Environmental priorities and targets for emission reductions are important for defining energy policy in Denmark. As the energy supply sector at present is a major contributor to emissions of CO2 and SO2, knowledge of this sector is vital for reducing these emissions......This paper examines structural change in the power and heat producing sector (energy supply) and its implications for the economy. An integrated approach is used to describe the interactions between this sector and the rest of the economy. Thus, a very detailed model of the sector for Denmark has...... been linked to a macroeconometric model of the Danish economy. It is argued that analysing sectors that undergo radical changes, for example, the energy supply sector should be undertaken by using a model that describes the technological and organisational changes in production along with implications...

  2. Structural changes of ultrasonicated bovine serum albumin revealed by hydrogen-deuterium exchange and mass spectrometry.

    Science.gov (United States)

    Zhang, Qiuting; Tu, Zongcai; Wang, Hui; Huang, Xiaoqin; Sha, Xiaomei; Xiao, Hui

    2014-11-01

    The structural changes of bovine serum albumin (BSA) under high-intensity ultrasonication were investigated by fluorescence spectroscopy and mass spectrometry. Evidence for the ultrasonication-induced conformational changes of BSA was provided by the intensity changes and maximum-wavelength shift in fluorescence spectrometry. Matrix-assisted laser desorption-ionization time-of-flight mass spectroscopy (MALDI-TOF MS) revealed the increased intensity of the peak at the charge state +5 and a newly emerged peak at charge state +6, indicating that the protein became unfolded after ultrasonication. Prevalent unfolding of BSA after ultrasonication was revealed by hydrogen-deuterium exchange coupled with mass spectrometry (HDX-MS). Increased intensity and duration of ultrasonication further promoted the unfolding of the protein. The unfolding induced by ultrasonication goes through an intermediate state similar to that induced by a low concentration of denaturant.

  3. Efficacy of Structured Organizational Change Intervention on HIV Testing in Correctional Facilities.

    Science.gov (United States)

    Belenko, Steven; Visher, Christy; Pearson, Frank; Swan, Holly; Pich, Michele; O'Connell, Daniel; Dembo, Richard; Frisman, Linda; Hamilton, Leah; Willett, Jennifer

    2017-06-01

    This article presents findings from a multisite cluster randomized trial of a structured organizational change intervention for improving HIV testing services in jails and prisons. Matched pairs of prison and jail facilities were randomized to experimental and control conditions; all facilities received baseline training about best practices in HIV testing and other HIV services and selected an area of HIV services on which to focus improvement efforts. The experimental facilities formed local change teams and were provided external coaching based on the Network for the Improvement of Addiction Treatment (NIATx) process improvement model. Difference-indifference analyses indicate a significant relative increase in HIV testing in the experimental compared to the control condition. Meta-analyses across the matched pairs indicated a small to medium effect of increased testing overall. The results indicate that the local change team model can achieve significant increases in HIV testing in correctional facilities. Implications for HIV testing policies and challenges for expanding testing are discussed.

  4. Bone Structural Changes and Estimated Strength After Gastric Bypass Surgery Evaluated by HR-pQCT

    DEFF Research Database (Denmark)

    Frederiksen, Katrine Diemer; Hanson, Stine; Hansen, Stinus

    2016-01-01

    Roux-en-Y gastric bypass surgery (RYGB) is an effective treatment of morbid obesity, with positive effects on obesity-related complications. The treatment is associated with bone loss, which in turn might increase fracture risk. The aim of this study was to evaluate changes in bone mineral densit...... increased risk of fracture in bariatric patients after surgery. We only observed bone structural changes in the weight-bearing bone, which indicates that mechanical un-loading is the primary mediator.......Roux-en-Y gastric bypass surgery (RYGB) is an effective treatment of morbid obesity, with positive effects on obesity-related complications. The treatment is associated with bone loss, which in turn might increase fracture risk. The aim of this study was to evaluate changes in bone mineral density...

  5. Structure and strength of carbide-steel cermet and their changes during heat treatment

    International Nuclear Information System (INIS)

    Dariel, M.P.; Frage, N.R.; Kaputkina, L.M.; Kaputkin, D.M.; Sverdlova, N.R.

    2004-01-01

    Both homogeneous and 'graded' materials were produced by pressing and sintering of titanium carbide TiC x (0.7 x takes place during the joining. If the titanium carbide is carbon deficient that the carbon goes from the steel binder to TiC x , and this redistribution intensity with the x decreases. So-named graded cermets were produced on controlled distribution of TiC x with different x. An additional flow of carbon from C-rich to C-poor TiC x layers was obtained in these cermets. These changes both in the steel and TiC x compositions result in changes in such processes as austenitization, carbide dissolution and precipitation, and martensitic transformation. Both general strength of the material and the gradient of properties in graded cermets can be increased using kinetic factors of element redistribution and structure changes resulted from the heat treatment. (author)

  6. Structural Change, Economic Growth and the Environmental Kuznets Curve. A Theoretical Perspective

    International Nuclear Information System (INIS)

    De Groot, H.L.F.

    1999-01-01

    The question of whether economic growth will ultimately resolve environmental problems has recently been discussed in a mainly empirical literature. One of the mechanisms that can explain the finding of an inverted U-shaped relationship between income and emissions relies on the changes in the sectoral composition of economies associated with economic growth. This paper develops a multi-sector general-equilibrium model to study the dynamic relationships between technological progress, economic development, the sectoral composition of economies and emissions. In the model, structural change is the outcome of a complex interplay between factors of demand and supply, and results from both differences in technological progress on a sectoral level and from differences in income elasticities of demand for different goods. We will derive under what conditions such changes can give rise to a hump-shaped relationship between per capita income and emissions. 39 refs

  7. Influence of the local structure in phase-change materials on their dielectric permittivity.

    Science.gov (United States)

    Shportko, Kostiantyn V; Venger, Eugen F

    2015-01-01

    Ge-Sb-Te alloys, which belong to the phase-change materials, are promising materials for data storage and display and data visualization applications due to their unique properties. This includes a remarkable difference of their electrical and optical properties in the amorphous and crystalline state. Pronounced change of optical properties for Ge-Sb-Te alloys is linked to the different bonding types and different atomic arrangements in amorphous and crystalline states. The dielectric function of phase-change materials has been investigated in the far infrared (FIR) range. Phonons have been detected by FTIR spectroscopy. Difference of the dispersion of the dielectric permittivity of amorphous and crystalline samples is caused by different structures in different states which contribute to the dielectric permittivity.

  8. Survey of Lignin-Structure Changes and Depolymerization during Ionic Liquid Pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, Tanmoy; Isern, Nancy G.; Sun, Jian; Wang, Eileen; Hull, Sarah; Cort, John R.; Simmons, Blake A.; Singh, Seema

    2017-09-26

    A detailed study of chemical changes in lignin structure during the ionic liquid (IL) pretreatment process is not only pivotal for understanding and overcoming biomass recalcitrance during IL pretreatment, but also is necessary for designing new routes for lignin valorization. Chemical changes in lignin were systematically studied as a function of pretreatment temperature, time and type of IL used. Kraft lignin was used as the lignin source and common pretreatment conditions were employed using three different ILs of varying chemical structure in terms of acidic or basic character. The chemical changes in the lignin structure due to IL pretreatment processes were monitored using 1H-13C HSQC NMR, 31P NMR, elemental analysis, GPC, FT-IR, and the depolymerized products were analyzed using GC-MS. Although pretreatment in acidic IL, triethylammonium hydrogensulfate ([TEA][HSO4]) results in maximum decrease in β-aryl ether bond, maximum dehydration and recondensation pathways were also evident, with the net process showing a minimum decrease in the molecular weight of regenerated lignin. However, 1-ethyl-3-methylimidazolium acetate ([C2C1Im][OAc]) pretreatment yields a smaller decrease in the β-aryl ether content along with minimum evidence of recondensation, resulting in the maximum decrease in the molecular weight. Cholinium lysinate ([Ch][Lys]) pretreatment shows an intermediate result, with moderate depolymerization, dehydration and recondensation observed. The depolymerization products after IL pretreatment are found to be a function of the pretreatment temperature and the specific chemical nature of the IL used. At higher pretreatment temperature, [Ch][Lys] pretreatment yields guaiacol, [TEA][HSO4] yields guaiacylacetone, and [C2C1Im][OAc] yields both guaiacol and guaiacylacetone as major products. These results clearly indicate that the changes in lignin structure as well as the depolymerized product profile depend on the pretreatment conditions and the nature

  9. Changes of brain structure in Parkinson's disease patients with mild cognitive impairment analyzed via VBM technology.

    Science.gov (United States)

    Gao, Yuyuan; Nie, Kun; Huang, Biao; Mei, Mingjin; Guo, Manli; Xie, Sifen; Huang, Zhiheng; Wang, Limin; Zhao, Jiehao; Zhang, Yuhu; Wang, Lijuan

    2017-09-29

    To analyze changes in cerebral grey matter volume and white matter density in non-dementia Parkinson's disease patients using voxel-based morphometry (VBM) technology; to investigate features of brain structure changes in Parkinson's disease patients with mild cognitive impairment (PD-MCI), and reveal their intrinsic pathological changes. Based on the diagnostic criteria of PD-MCI, 23 PD-MCI patients, 23 Parkinson's disease patients with normal cognition (PD-NC), and 21 age- and gender-matched healthy people were recruited for the study. Scans were performed on all subjects on a 3.0T MR scanner to obtain brain structural magnetic resonance images. Images were preprocessed using the VBM8 tool from SPM8 software package on the Matlab R2008a platform, and data were then analyzed using the SPM statistical software package to compare the differences of grey matter volume and white matter density between groups, and to evaluate the brain structural changes corresponding to the overall cognitive function. Compared to the control group, the PD-NC group suffered from grey matter atrophy, mainly found in the prefrontal lobe, limbic lobe and left temporal gyrus. The PD-MCI group suffered from grey matter atrophy found in the frontal lobe, limbic lobe, basal ganglia and cerebellum. Compared to the PD-NC group, the PD-MCI group suffered from grey matter atrophy found in the left-side middle temporal gyrus, inferior temporal gyrus and frontal lobe. The grey matter regions correlated with MMSE score (mainly memory related) including the right cingulate gyrus and the limbic lobe. The grey matter regions correlated with MoCA score (mainly non-memory related) including the frontal lobe, basal ganglia, parahippocampal gyrus, occipital lobe and the cerebellum. Additionally, overall cognitive function in non-dementia PD was mainly located in the frontal and limbic system, and was dominated by subcortical atrophy. Structural changes in PD-MCI patients are associated with overall

  10. Changes in cardiac structure and function among elite judoists resulting from long-term judo practice.

    Science.gov (United States)

    Laskowski, R; Wysocki, K; Multan, A; Haga, S

    2008-09-01

    The aim of this study was to investigate the character of changes in cardiac structure and function among elite judoists due to long-term judo practice. A group of male (N = 20, average age: 22.1) and female (N = 15, average age: 19.4) athletes practising judo for about 10 years was subjected to echocardiographic tests carried out during rest (aorta diameter [AoD], diastolic dimension of the left ventricle [Dd], thickness of the interventricular septum [IVST], the thickness of the posterior wall of the left ventricle [LVPWT]), and to measurement of cardiovascular system's action parameters (heart rate [HR], stroke volume [SV], cardiac output [Q], blood pressure [BP]). Moreover, control non trained subjects were also studied, women (N = 30, average age: 19.1) and men (N = 30, average age: 21.4). In order to determine aerobic efficiency, the authors measured the maximal oxygen uptake (VO2max) using the direct method. The anaerobic capacity was estimated on the basis of the maximal anaerobic power, and the volume of the performed work was calculated by means of the 30s Wingate test. Echocardiographic test values imply that changes in heart morphology induced by long term judo training, such as increase diastolic dimension of the left ventricle, thickness of the interventricular septum and left ventricular posterior wall, resemble more the changes observed in endurance athletes than changes observed in strength athletes. The obtained data indicated that judo training improves both aerobic and anerobic performance and these changes were associated with changes in heart structure and function as compared to non trained control.

  11. The Spacing Effect for Structural Synaptic Plasticity Provides Specificity and Precision in Plastic Changes.

    Science.gov (United States)

    San Martin, Alvaro; Rela, Lorena; Gelb, Bruce; Pagani, Mario Rafael

    2017-05-10

    disability, such as Noonan syndrome. Although LTM is sustained by structural synaptic plasticity, how synapses integrate spaced stimuli and decode them into specific plastic changes remains elusive. Here, we show that the spacing effect is a phenomenon detected at the synaptic level, which determines the properties of the response in structural plasticity, including precision of such response. Whereas suppressing or enhancing Ras/mitogen-activated protein kinase signaling changed how synapses decode a pattern of stimuli, a disease-related Ras allele abolished the spacing effect for plastic changes. Copyright © 2017 the authors 0270-6474/17/374992-16$15.00/0.

  12. Structural changes of a sodium dodecyl sulfate (SDS) micelle induced by alcohol molecules.

    Science.gov (United States)

    Méndez-Bermúdez, Jose G; Dominguez, Hector

    2016-01-01

    Coarse-grained dynamical simulations have been performed to investigate the behavior of a surfactant micelle in the presence of six different alcohols: hexanol, octanol, decanol, dodecanol, tetradecanol, and hexadecanol. The self-assembly of sodium dodecyl sulfate (SDS) is modified by the alcohol molecules into cylindrical and bilayer micelles as a function of the alcohol/SDS mass ratio. Therefore, in order to understand, from a molecular point of view, how SDS and alcohol molecules self-organize to form the new micelles, different studies were carried out. Analysis of micelle structures, density profiles, and parameters of order were conducted to characterize the shape and size of those micelles. The density profiles revealed that the alcohol molecules were located at the water-micelle interface next to the SDS molecules at low alcohol/SDS mass ratio. At high alcohol/SDS mass ratios, alcohol molecules moved to the middle of the micelle by increasing their size and by producing a structural change. Moreover, micelle structures and sizes were influenced not only by the alcohol/SDS mass ratio but also by the order of the SDS and alcohol tails. Finally, the size of the micelles and enthalpy calculations were used as order parameters to determine a structural phase diagram of alcohol/SDS mixtures in water. Graphical Abstract Structural transition of SDS/alcohol mixtures.

  13. Revisiting local structural changes in GeO2 glass at high pressure.

    Science.gov (United States)

    Dong, Juncai; Yao, HuRong; Guo, Zhiying; Jia, Quanjie; Wang, Yan; An, Pengfei; Gong, Yu; Liang, Yaxiang; Chen, Dongliang

    2017-09-18

    Despite the great importance in fundamental and industrial fields, understanding structural changes for pressure-induced polyamorphism in network-forming glasses remains a formidable challenge. Here, we revisited the local structural transformations in GeO2 glass up to 54 GPa using x-ray absorption fine structure (XAFS) spectroscopy via a combination diamond anvil cell and polycapillary half-lens. Three polyamorphic transitions can be clearly identified by XAFS structure refinement. First, a progressive increase of the nearest Ge-O distance and bond disorder to a maximum at ~5-16 GPa, in the same pressure region of previously observed tetrahedral-octahedral transformation. Second, a markedly decrease of the nearest Ge-O distance at ~16-22.6 GPa but a slight increase at ~22.6-32.7 GPa, with a concomitant decrease of bond disorder. This stage can be related to a second-order-like transition from less dense to dense octahedral glass. Third, another decrease in the nearest Ge-O distance at ~32.7-41.4 GPa but a slight increase up to 54 GPa, synchronized with a gradual increase of bond disorder. This stage provides strong evidence for ultrahigh-pressure polyamorphism with coordination number >6. Furthermore, cooperative modification is observed in more distant shells. Those results provide a unified local structural picture for elucidating the polyamorphic transitions and densification process in GeO2 glass. © 2017 IOP Publishing Ltd.

  14. Revisiting local structural changes in GeO2 glass at high pressure.

    Science.gov (United States)

    Dong, Juncai; Yao, Hurong; Guo, Zhiying; Jia, Quanjie; Wang, Yan; An, Pengfei; Gong, Yu; Liang, Yaxiang; Chen, Dongliang

    2017-10-20

    Despite the great importance in fundamental and industrial fields, understanding structural changes for pressure-induced polyamorphism in network-forming glasses remains a formidable challenge. Here, we revisited the local structural transformations in GeO 2 glass up to 54 GPa using x-ray absorption fine structure (XAFS) spectroscopy via a combination diamond anvil cell and polycapillary half-lens. Three polyamorphic transitions can be clearly identified by XAFS structure refinement. First, a progressive increase of the nearest Ge-O distance and bond disorder to a maximum at ~5-16 GPa, in the same pressure region of previously observed tetrahedral-octahedral transformation. Second, a marked decrease of the nearest Ge-O distance at ~16-22.6 GPa but a slight increase at ~22.6-32.7 GPa, with a concomitant decrease of bond disorder. This stage can be related to a second-order-like transition from less dense to dense octahedral glass. Third, another decrease in the nearest Ge-O distance at ~32.7-41.4 GPa but a slight increase up to 54 GPa, synchronized with a gradual increase of bond disorder. This stage provides strong evidence for ultrahigh-pressure polyamorphism with coordination number  >6. Furthermore, cooperative modification is observed in more distant shells. Those results provide a unified local structural picture for elucidating the polyamorphic transitions and densification process in GeO 2 glass.

  15. Phytoestrogens and Mycoestrogens Induce Signature Structure Dynamics Changes on Estrogen Receptor α

    Directory of Open Access Journals (Sweden)

    Xueyan Chen

    2016-08-01

    Full Text Available Endocrine disrupters include a broad spectrum of chemicals such as industrial chemicals, natural estrogens and androgens, synthetic estrogens and androgens. Phytoestrogens are widely present in diet and food supplements; mycoestrogens are frequently found in grains. As human beings and animals are commonly exposed to phytoestrogens and mycoestrogens in diet and environment, it is important to understand the potential beneficial or hazardous effects of estrogenic compounds. Many bioassays have been established to study the binding of estrogenic compounds with estrogen receptor (ER and provided rich data in the literature. However, limited assays can offer structure information with regard to the ligand/ER complex. Our current study surveys the global structure dynamics changes for ERα ligand binding domain (LBD when phytoestrogens and mycoestrogens bind. The assay is based on the structure dynamics information probed by hydrogen deuterium exchange mass spectrometry and offers a unique viewpoint to elucidate the mechanism how phytoestrogens and mycoestrogens interact with estrogen receptor. The cluster analysis based on the hydrogen deuterium exchange (HDX assay data reveals a unique pattern when phytoestrogens and mycoestrogens bind with ERα LBD compared to that of estradiol and synthetic estrogen modulators. Our study highlights that structure dynamics could play an important role in the structure function relationship when endocrine disrupters interact with estrogen receptors.

  16. Patterns and structures of land use change in the Three Rivers Headwaters Region of China.

    Directory of Open Access Journals (Sweden)

    Jingbiao Yang

    Full Text Available Located in Qinghai Province of China, the Three Rivers Headwaters Region is the source region of the Yangtze, Yellow and Lantsang Rivers, and plays an important role in biodiversity conservation and regulating water supply. Despite many efforts on land use change in Qinghai, knowledge of the spatial variation of land use change is still lacking. This study examines the patterns of land use change across various watersheds, prefectures and the temple surroundings. Remote sensing images of 1987, 1997 and 2007 were analyzed to derive land use distributions; patterns and structures of the landscape were then quantified with landscape metrics. The results illustrated that the Yangtze River headwater region had more diverse and more evenly distributed landscape, while the Lantsang and the Yellow headwater regions showed a decline in landscape diversity. Comparison of the land use patterns of four prefectures revealed that Yushu Prefecture experienced an increase in landscape diversity from 1987 to 2007 while the land use patches in Guoluo Prefecture exhibited more aggregated patterns than other prefectures. Analysis of the spatial variations of land use change in the temple surroundings illustrated that 19.7% and 35.9% of the temples in Guoluo and Yushu Prefectures, respectively, encountered land use change for their immediate areas within 2 km. Comparison of the surroundings of temples and human settlements found that land use change was not evenly distributed, and that greater land use change had occurred for the surroundings of human settlements. Such findings provided insights into the spatial variation of land use change in the Three Rivers Headwaters Region.

  17. Between information systems and physical structure of the city: New causes of climate changes

    Directory of Open Access Journals (Sweden)

    Mihajlov Vladimir

    2011-01-01

    Full Text Available Because of the frequent and significant spatial transformations, an increasing climate change regime in urban areas occurs. In this paper a comprehensive reflection on these changes is analyzed, concerning one of the major causes - the social transformation and the growing use of information, networks and technology, used by city dwellers in everyday life. Advanced communications and the Internet provide urban concentration and decentralization, creating new spatial and geographic network, with a new allocation of space, for manufacturing and services. The consequence may be recognized in increasing individualization and social habits of city dwellers, as well as in modified way of households use, changing neighbourhoods and public spaces, transport systems, as the final outcome is the climate change. In this paper, the interdependence between information networks is emphasized - between virtual and physical environment, as well as changes in the way of life of the city, which ultimately lead to a new trigger for climate change. Users have never been more mobile in the physical space (commuting and tourist travel, while in the virtual space they are associated with the fixed points - everybody can be located, by using email or social network. Unexpectedly, the cause of the problem which is considered in this paper, is increased mobility in the real space, while city dwellers remain in one place, by using their virtual electronic connections. Thus, the role of city dwellers in creating climate change depends upon their spatial distribution and relationship towards information's and network activity. As a result, the drivers in city development are recognized on network nodes. Current crises in the global environment (economic, climate and social indicate the need to develop multi-functional environment and a greater appreciation of natural factors. Therefore, as a decisive factor for the adaptation of urban structure on climate change is the

  18. Verrucomicrobial community structure and abundance as indicators for changes in chemical factors linked to soil fertility.

    Science.gov (United States)

    Navarrete, Acacio Aparecido; Soares, Tielle; Rossetto, Raffaella; van Veen, Johannes Antonie; Tsai, Siu Mui; Kuramae, Eiko Eurya

    2015-09-01

    Here we show that verrucomicrobial community structure and abundance are extremely sensitive to changes in chemical factors linked to soil fertility. Terminal restriction fragment length polymorphism fingerprint and real-time quantitative PCR assay were used to analyze changes in verrucomicrobial communities associated with contrasting soil nutrient conditions in tropical regions. In case study Model I ("Slash-and-burn deforestation") the verrucomicrobial community structures revealed disparate patterns in nutrient-enriched soils after slash-and-burn deforestation and natural nutrient-poor soils under an adjacent primary forest in the Amazonia (R = 0.819, P = 0.002). The relative proportion of Verrucomicrobia declined in response to increased soil fertility after slash-and-burn deforestation, accounting on average, for 4 and 2 % of the total bacterial signal, in natural nutrient-poor forest soils and nutrient-enriched deforested soils, respectively. In case study Model II ("Management practices for sugarcane") disparate patterns were revealed in sugarcane rhizosphere sampled on optimal and deficient soil fertility for sugarcane (R = 0.786, P = 0.002). Verrucomicrobial community abundance in sugarcane rhizosphere was negatively correlated with soil fertility, accounting for 2 and 5 % of the total bacterial signal, under optimal and deficient soil fertility conditions for sugarcane, respectively. In nutrient-enriched soils, verrucomicrobial community structures were related to soil factors linked to soil fertility, such as total nitrogen, phosphorus, potassium and sum of bases, i.e., the sum of calcium, magnesium and potassium contents. We conclude that community structure and abundance represent important ecological aspects in soil verrucomicrobial communities for tracking the changes in chemical factors linked to soil fertility under tropical environmental conditions.

  19. Revisiting the Neural Basis of Acquired Amusia: Lesion Patterns and Structural Changes Underlying Amusia Recovery

    Science.gov (United States)

    Sihvonen, Aleksi J.; Ripollés, Pablo; Rodríguez-Fornells, Antoni; Soinila, Seppo; Särkämö, Teppo

    2017-01-01

    Although, acquired amusia is a common deficit following stroke, relatively little is still known about its precise neural basis, let alone to its recovery. Recently, we performed a voxel-based lesion-symptom mapping (VLSM) and morphometry (VBM) study which revealed a right lateralized lesion pattern, and longitudinal gray matter volume (GMV) and white matter volume (WMV) changes that were specifically associated with acquired amusia after stroke. In the present study, using a larger sample of stroke patients (N = 90), we aimed to replicate and extend the previous structural findings as well as to determine the lesion patterns and volumetric changes associated with amusia recovery. Structural MRIs were acquired at acute and 6-month post-stroke stages. Music perception was behaviorally assessed at acute and 3-month post-stroke stages using the Scale and Rhythm subtests of the Montreal Battery of Evaluation of Amusia (MBEA). Using these scores, the patients were classified as non-amusic, recovered amusic, and non-recovered amusic. The results of the acute stage VLSM analyses and the longitudinal VBM analyses converged to show that more severe and persistent (non-recovered) amusia was associated with an extensive pattern of lesions and GMV/WMV decrease in right temporal, frontal, parietal, striatal, and limbic areas. In contrast, less severe and transient (recovered) amusia was linked to lesions specifically in left inferior frontal gyrus as well as to a GMV decrease in right parietal areas. Separate continuous analyses of MBEA Scale and Rhythm scores showed extensively overlapping lesion pattern in right temporal, frontal, and subcortical structures as well as in the right insula. Interestingly, the recovered pitch amusia was related to smaller GMV decreases in the temporoparietal junction whereas the recovered rhythm amusia was associated to smaller GMV decreases in the inferior temporal pole. Overall, the results provide a more comprehensive picture of the lesions

  20. Revisiting the Neural Basis of Acquired Amusia: Lesion Patterns and Structural Changes Underlying Amusia Recovery

    Directory of Open Access Journals (Sweden)

    Aleksi J. Sihvonen

    2017-07-01

    Full Text Available Although, acquired amusia is a common deficit following stroke, relatively little is still known about its precise neural basis, let alone to its recovery. Recently, we performed a voxel-based lesion-symptom mapping (VLSM and morphometry (VBM study which revealed a right lateralized lesion pattern, and longitudinal gray matter volume (GMV and white matter volume (WMV changes that were specifically associated with acquired amusia after stroke. In the present study, using a larger sample of stroke patients (N = 90, we aimed to replicate and extend the previous structural findings as well as to determine the lesion patterns and volumetric changes associated with amusia recovery. Structural MRIs were acquired at acute and 6-month post-stroke stages. Music perception was behaviorally assessed at acute and 3-month post-stroke stages using the Scale and Rhythm subtests of the Montreal Battery of Evaluation of Amusia (MBEA. Using these scores, the patients were classified as non-amusic, recovered amusic, and non-recovered amusic. The results of the acute stage VLSM analyses and the longitudinal VBM analyses converged to show that more severe and persistent (non-recovered amusia was associated with an extensive pattern of lesions and GMV/WMV decrease in right temporal, frontal, parietal, striatal, and limbic areas. In contrast, less severe and transient (recovered amusia was linked to lesions specifically in left inferior frontal gyrus as well as to a GMV decrease in right parietal areas. Separate continuous analyses of MBEA Scale and Rhythm scores showed extensively overlapping lesion pattern in right temporal, frontal, and subcortical structures as well as in the right insula. Interestingly, the recovered pitch amusia was related to smaller GMV decreases in the temporoparietal junction whereas the recovered rhythm amusia was associated to smaller GMV decreases in the inferior temporal pole. Overall, the results provide a more comprehensive picture of

  1. Revisiting the Neural Basis of Acquired Amusia: Lesion Patterns and Structural Changes Underlying Amusia Recovery.

    Science.gov (United States)

    Sihvonen, Aleksi J; Ripollés, Pablo; Rodríguez-Fornells, Antoni; Soinila, Seppo; Särkämö, Teppo

    2017-01-01

    Although, acquired amusia is a common deficit following stroke, relatively little is still known about its precise neural basis, let alone to its recovery. Recently, we performed a voxel-based lesion-symptom mapping (VLSM) and morphometry (VBM) study which revealed a right lateralized lesion pattern, and longitudinal gray matter volume (GMV) and white matter volume (WMV) changes that were specifically associated with acquired amusia after stroke. In the present study, using a larger sample of stroke patients ( N = 90), we aimed to replicate and extend the previous structural findings as well as to determine the lesion patterns and volumetric changes associated with amusia recovery. Structural MRIs were acquired at acute and 6-month post-stroke stages. Music perception was behaviorally assessed at acute and 3-month post-stroke stages using the Scale and Rhythm subtests of the Montreal Battery of Evaluation of Amusia (MBEA). Using these scores, the patients were classified as non-amusic, recovered amusic, and non-recovered amusic. The results of the acute stage VLSM analyses and the longitudinal VBM analyses converged to show that more severe and persistent (non-recovered) amusia was associated with an extensive pattern of lesions and GMV/WMV decrease in right temporal, frontal, parietal, striatal, and limbic areas. In contrast, less severe and transient (recovered) amusia was linked to lesions specifically in left inferior frontal gyrus as well as to a GMV decrease in right parietal areas. Separate continuous analyses of MBEA Scale and Rhythm scores showed extensively overlapping lesion pattern in right temporal, frontal, and subcortical structures as well as in the right insula. Interestingly, the recovered pitch amusia was related to smaller GMV decreases in the temporoparietal junction whereas the recovered rhythm amusia was associated to smaller GMV decreases in the inferior temporal pole. Overall, the results provide a more comprehensive picture of the lesions

  2. Nearshore energy subsidies support Lake Michigan fishes and invertebrates following major changes in food web structure

    Science.gov (United States)

    Turschak, Benjamin A; Bunnell, David B.; Czesny, Sergiusz J.; Höök, Tomas O.; Janssen, John; Warner, David M.; Bootsma, Harvey A

    2014-01-01

    Aquatic food webs that incorporate multiple energy channels (e.g. nearshore benthic or pelagic) with varying productivity and turnover rates convey stability to biological communities by providing multiple independent energy sources. Within the Lake Michigan food web, invasive dreissenid mussels have caused rapid changes to food web structure and potentially altered the channels through which consumers acquire energy. We used stable C and N isotopes to determine how Lake Michigan food web structure has changed in the past decade, coincident with the expansion of dreissenid mussels, decreased pelagic phytoplankton production and increased nearshore benthic algal production. Fish and invertebrate samples collected from sites around Lake Michigan were analyzed to determine taxa-specific 13C:12C (delta 13C) and 15N:14N (delta 15N) ratios. Sampling took place during two distinct periods, 2002-2003 and 2010-2012, that spanned the period of dreissenid expansion, and included nearshore, pelagic and profundal fish and invertebrate taxa. Magnitude and direction of the 13C shift indicated significantly greater reliance upon nearshore benthic energy sources among nearly all fish taxa as well as profundal invertebrates. Although the mechanisms underlying this 13C shift likely varied among species, possible causes include the transport of benthic algal production to offshore waters and an increased reliance on nearshore prey items. Delta 15N shifts were more variable and of smaller magnitude across taxa although declines in delta 15N among some pelagic fishes may indicate a shift to alternative prey resources. Lake Michigan fishes and invertebrates appear to have responded to dreissenid induced changes in nutrient and energy pathways by switching from pelagic to alternative nearshore energy subsidies. Although large shifts in energy allocation (i.e. pelagic to nearshore benthic) resulting from invasive species appear to have affected total production at upper trophic

  3. Annealing assisted structural and surface morphological changes in Langmuir–Blodgett films of nickel octabutoxy phthalocyanine

    Energy Technology Data Exchange (ETDEWEB)

    Shilpa Harish, T.; Viswanath, P., E-mail: viswanath@cnsms.res.in

    2016-01-01

    We report our studies on thin films of metallo-phthalocyanine (MPc), Nickel(II)1,4,8,11,15,18,22,25-octabutoxy-29H,31H-phthalocyanine (NiPc(OBu){sub 8}) transferred in a well defined thermodynamic state over a self assembled monolayer (octadecyl trichlorosilane)/SiO{sub 2}/Si substrate using the Langmuir–Blodgett (LB) method. The films are characterized using differential scanning calorimetry (DSC), grazing incidence X-ray diffraction (GIXD) and atomic force microscopy (AFM) techniques. DSC studies on powdered samples in the bulk indicate enantiotropic solid–solid phase transition. GIXD studies on the as-deposited LB film show a Bragg peak indicating crystallinity of the thin film. Annealing (373 K) results in reduction of lattice spacing (1.21 Å) signifying changes in molecular packing within the unit cell. At this stage, an additional Bragg peak is observed which grows at the expense of the former one and they coexist between 373 K and 423 K. A discontinuity in lattice spacing from 20.73 to 15.12 Å with annealing indicates clearly a structural change of the underlying crystalline lattice. Correspondingly, the surface morphology images obtained using AFM show, with annealing, a transformation from spherical granular morphology to elongated, flat crystallites suggesting asymmetric growth process. Statistical parameters of the grain extracted from the AFM images show that the size, fractal dimension and circularity are affected by annealing. Based on these studies, we infer the structural and surface morphological changes of the meta-stable phase (Form I) to the stable phase (Form II) in annealed LB films of phthalocyanine. - Highlights: • Langmuir–Blodgett (LB) films of phthalocyanine subjected to thermal annealing. • Structural transformation and coexistence of polymorphs in LB films • Surface morphology changes from nanoscale grains to elongated crystallites. • Reduction of fractal dimension and circularity index reveals asymmetric growth.

  4. Structural changes and tribological performance of thermosetting polyimide induced by proton and electron irradiation

    International Nuclear Information System (INIS)

    Lv, Mei; Wang, Yanming; Wang, Qihua; Wang, Tingmei; Liang, Yongmin

    2015-01-01

    The structural changes and tribological performance of thermosetting polyimide were investigated by electron, proton or both combined irradiations at 25 keV in a ground-based simulation facility. Three forms of irradiations could lead to the formation of the carbonized layer on the polymer surface that could increase the hardness and adhesive force of the material. Proton irradiation induced more extensive changes in structure and friction behavior than electron irradiation by reason of the higher linear energy transfer value, and combined irradiation resulted in the largest impact, but which was less than the sum of the radiation effects of electron and proton. Moreover, the experimental results indicated that the changes in friction behavior are closely related with the carbonized layer, which was easily worn out in friction process and could introduce a shift from adhesion wear to three-body abrasive wear that reduced the wear rate and the friction coefficient. The friction process of irradiated samples could be divided into the initial stage and the steady stage. Three forms of irradiations all induced the high friction coefficient in the initial stage and the low friction coefficient in the steady stage, and the wear rate of the irradiated samples decreased in the order: electron irradiation>proton irradiation>combined irradiation. - Highlights: • Proton irradiation induced more extensive changes in structure and friction behavior than electron irradiation. • The effect of combined irradiation was less than that of the sum of electron and proton irradiation. • Three forms of irradiations all induced the high initial friction coefficient and the low steady-stage friction coefficient. • The initial friction stage means a fast-wearing adhesive process while the steady-state of the system is a three-body abrasion

  5. Globalization and structural change in the U.S. forest sector: an evolving context for sustainable forest management

    Science.gov (United States)

    Peter Ince; Albert Schuler; Henry Spelter; William Luppold

    2007-01-01

    This report examines economic implications for sustainable forest management of globalization and related structural changes in the forest sector of the United States. Globalization has accelerated structural change in the U.S. forest sector, favored survival of larger and more capital-intensive enterprises, and altered historical patterns of resource use.

  6. CHANGES IN THE AGE STRUCTURE OF THE POPULATION AND ITS IMPACT ON THE FINANCIAL BALANCE OF VIETNAM PENSION FUND

    OpenAIRE

    Hung Tran Manh

    2014-01-01

    The article analyzes the changing in theage structure of the Vietnam population in the period from 1979 to the present, andthe trend of its changes between now and2049. It deals with the impact of changesin the age structure on the fi nancial balance of the Pension Fund of Vietnam in conditions of population aging.

  7. The secondary and aggregation structural changes of BSA induced by trivalent chromium: A biophysical study

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Mingmao [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002, Fujian (China); Liu, Yan, E-mail: liuyan@fjirsm.ac.cn [The State Key Lab of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian (China); Cao, Huan [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002, Fujian (China); Song, Ling [The State Key Lab of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian (China); Zhang, Qiqing, E-mail: zhangqiq@126.com [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002, Fujian (China)

    2015-02-15

    Trivalent chromium Cr(III), which was originally considered to be innocuous as a nutriment, has been suspected to induce some abnormalities in human body recently. In the present work, the effects of Cr(III) on the structural state of BSA were comprehensively investigated through a series of appropriate methods in combination, including X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FTIR), circular dichroism (CD), UV–vis absorption, synchronous fluorescence, fluorescence lifetime analysis, resonance light scattering (RLS), dynamic light scattering (DLS) and excitation–emission matrix spectroscopy (EEMS) methods. XPS accurately described the binding activity of Cr(III) with protein C, N and O atoms. The structural analysis according to FTIR and CD methods showed that the Cr(III) binding altered BSA conformation with a major reduction of α-helix. RLS and DLS analyses demonstrated that the presence of Cr(III) with low concentration could induce the aggregation structural changes of BSA. UV–vis absorption, EEMS and synchronous fluorescence suggested that the interaction between Cr(III) and BSA induced a slight unfolding of the polypeptide backbone and altered the microenvironments of Trp and Tyr residues in BSA. This research is helpful for understanding the structure-function relationship involved in metal ion-protein bioconjugate process. - Highlights: • The effect of Cr(III) on the conformational state of BSA was comprehensively studied. • XPS described the binding activity of Cr(III) with protein C, N and O atoms. • FTIR and CD data revealed secondary structural alteration in BSA. • Cr(III) complexation induced microenvironmental changes of Trp and Tyr. • RLS, DLS and EEMS presented the aggregational states of Cr(III)–BSA complex.

  8. In-Situ Reflectometry Observation on Structural Changes of Thin Self-Assembled Block Copolymer Films

    International Nuclear Information System (INIS)

    Torikai, N; Yamada, N L; Kawaguchi, D; Takano, A; Matsushita, Y; Watkins, E; Majewski, J P; Okuda, H

    2007-01-01

    The structural changes induced by solvent contact or heating were observed for thin spin-coated polystyrene-block-poly(2-vinylpyridine) diblock copolymer (PS-P2VP) films using in-situ neutron reflectivity and grazing-incidence small-angle X-ray scattering (GISAXS) techniques. The lamellarly-ordered PS-P2VP film showed some structural changes in contact with water though it is a poor solvent for both the component polymers, while the original structure was recovered after drying the film. When toluene was used as a selectively good solvent for PS, the thin film was dissolved into the solvent. On the other hand, the thin as-prepared PS-P2VP film with spherical microdomains exhibited laterally a pair of scattering spots symmetrical relative to the specular reflection ridge in the GISAXS pattern, indicating the existence of some lateral structural correlation in the film. On a temperature jump up to 200 0 C, these two scattering spots started to disappear around the glass transition temperature, and then almost completely vanished at 200 0 C unexpectedly though the PS-P2VP used here should be kept in the strong-segregation state. The spherical structure could be completely disordered or kept ordered but with lateral distortion in its orientation. Being cooled down to a room temperature again, the two scattering spots were recovered, and became more intense with their position shifting slightly to lower Q Y -region than before heating due to the improvement in ordering

  9. Classification of RNA structure change by ‘gazing’ at experimental data

    Science.gov (United States)

    Woods, Chanin Tolson

    2017-01-01

    Abstract Motivation: Mutations (or Single Nucleotide Variants) in folded RiboNucleic Acid structures that cause local or global conformational change are riboSNitches. Predicting riboSNitches is challenging, as it requires making two, albeit related, structure predictions. The data most often used to experimentally validate riboSNitch predictions is Selective 2′ Hydroxyl Acylation by Primer Extension, or SHAPE. Experimentally establishing a riboSNitch requires the quantitative comparison of two SHAPE traces: wild-type (WT) and mutant. Historically, SHAPE data was collected on electropherograms and change in structure was evaluated by ‘gel gazing.’ SHAPE data is now routinely collected with next generation sequencing and/or capillary sequencers. We aim to establish a classifier capable of simulating human ‘gazing’ by identifying features of the SHAPE profile that human experts agree ‘looks’ like a riboSNitch. Results: We find strong quantitative agreement between experts when RNA scientists ‘gaze’ at SHAPE data and identify riboSNitches. We identify dynamic time warping and seven other features predictive of the human consensus. The classSNitch classifier reported here accurately reproduces human consensus for 167 mutant/WT comparisons with an Area Under the Curve (AUC) above 0.8. When we analyze 2019 mutant traces for 17 different RNAs, we find that features of the WT SHAPE reactivity allow us to improve thermodynamic structure predictions of riboSNitches. This is significant, as accurate RNA structural analysis and prediction is likely to become an important aspect of precision medicine. Availability and Implementation: The classSNitch R package is freely available at http://classsnitch.r-forge.r-project.org. Contact: alain@email.unc.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:28130241

  10. Values, inter-attitudinal structure, and attitude change: value accessibility can increase a related attitude's resistance to change.

    Science.gov (United States)

    Blankenship, Kevin L; Wegener, Duane T; Murray, Renee A

    2015-12-01

    Accessibility is one of the most basic structural properties of an attitude and an important factor to consider in attitude strength. Despite its importance, relatively little work has examined the role of attitude accessibility in an inter-attitudinal context, particularly as it relates to the strength of related attitudes in the network. The present research examines accessibility as a property of one attitude (toward an abstract goal or end-state, that is, a value) that might influence the strength of a different but related attitude (toward a social policy conceptually related to the value). In Study 1, a highly accessible evaluative component of a value increased resistance to change of attitudes and behavioral intentions toward a social policy related to that value. Similarly, a manipulation of value accessibility (Studies 2 and 3) led to increased resistance of attitudes and behavioral intentions toward a social policy related to that value. Implications for the role of accessibility in inter-attitudinal strength are discussed. © 2015 by the Society for Personality and Social Psychology, Inc.

  11. The Changing Safety Net for Low-Income Parents and Their Children: Structural or Cyclical Changes in Income Support Policy?

    Science.gov (United States)

    Hardy, Bradley; Smeeding, Timothy; Ziliak, James P

    2018-02-01

    Refundable tax credits and food assistance are the largest transfer programs available to able-bodied working poor and near-poor families in the United States, and simultaneous participation in these programs has more than doubled since the early 2000s. To understand this growth, we construct a series of two-year panels from the 1981-2013 waves of the Current Population Survey Annual Social and Economic Supplement to estimate the effect of state labor-market conditions, federal and state transfer program policy choices, and household demographics governing joint participation in food and refundable tax credit programs. Overall, changing policy drives much of the increase in the simultaneous, biennial use of food assistance and refundable tax credits. This stands in stark contrast from the factors accounting for the growth in food assistance alone, where cyclical and structural labor market factors account for at least one-half of the growth, and demographics play a more prominent role. Moreover, since 2000, the business cycle factors as the leading determinant in biennial participation decisions in food programs and refundable tax credits, suggesting a recent strengthening in the relationship between economic conditions and transfer programs.

  12. Human and natural influences on the changing thermal structure of the atmosphere.

    Science.gov (United States)

    Santer, Benjamin D; Painter, Jeffrey F; Bonfils, Céline; Mears, Carl A; Solomon, Susan; Wigley, Tom M L; Gleckler, Peter J; Schmidt, Gavin A; Doutriaux, Charles; Gillett, Nathan P; Taylor, Karl E; Thorne, Peter W; Wentz, Frank J

    2013-10-22

    Since the late 1970s, satellite-based instruments have monitored global changes in atmospheric temperature. These measurements reveal multidecadal tropospheric warming and stratospheric cooling, punctuated by short-term volcanic signals of reverse sign. Similar long- and short-term temperature signals occur in model simulations driven by human-caused changes in atmospheric composition and natural variations in volcanic aerosols. Most previous comparisons of modeled and observed atmospheric temperature changes have used results from individual models and individual observational records. In contrast, we rely on a large multimodel archive and multiple observational datasets. We show that a human-caused latitude/altitude pattern of atmospheric temperature change can be identified with high statistical confidence in satellite data. Results are robust to current uncertainties in models and observations. Virtually all previous research in this area has attempted to discriminate an anthropogenic signal from internal variability. Here, we present evidence that a human-caused signal can also be identified relative to the larger "total" natural variability arising from sources internal to the climate system, solar irradiance changes, and volcanic forcing. Consistent signal identification occurs because both internal and total natural variability (as simulated by state-of-the-art models) cannot produce sustained global-scale tropospheric warming and stratospheric cooling. Our results provide clear evidence for a discernible human influence on the thermal structure of the atmosphere.

  13. Lake Michigan offshore ecosystem structure and food web changes from 1987 to 2008

    Science.gov (United States)

    Rogers, Mark W.; Bunnell, David B.; Madenjian, Charles P.; Warner, David M.

    2014-01-01

    Ecosystems undergo dynamic changes owing to species invasions, fisheries management decisions, landscape modifications, and nutrient inputs. At Lake Michigan, new invaders (e.g., dreissenid mussels (Dreissena spp.), spiny water flea (Bythotrephes longimanus), round goby (Neogobius melanostomus)) have proliferated and altered energy transfer pathways, while nutrient concentrations and stocking rates to support fisheries have changed. We developed an ecosystem model to describe food web structure in 1987 and ran simulations through 2008 to evaluate changes in biomass of functional groups, predator consumption, and effects of recently invading species. Keystone functional groups from 1987 were identified as Mysis, burbot (Lota lota), phytoplankton, alewife (Alosa pseudoharengus), nonpredatory cladocerans, and Chinook salmon (Oncorhynchus tshawytscha). Simulations predicted biomass reductions across all trophic levels and predicted biomasses fit observed trends for most functional groups. The effects of invasive species (e.g., dreissenid grazing) increased across simulation years, but were difficult to disentangle from other changes (e.g., declining offshore nutrient concentrations). In total, our model effectively represented recent changes to the Lake Michigan ecosystem and provides an ecosystem-based tool for exploring future resource management scenarios.

  14. Correlation between structural, optical and electrical properties anf the suitability of phase change alloys

    Energy Technology Data Exchange (ETDEWEB)

    Woda, Michael; Steimer, Christoph; Wamwangi, Daniel; Wuttig, Matthias [I. Insitute of Physics (IA), RWTH Aachen University, 52056 Aachen (Germany)

    2007-07-01

    Phase change random access memory (PCRAM) is a very promising candidate to replace Flash memories employed in the non-volatile storage sector. In the active region of this emerging memory, a phase change material is found. This class of materials is already used in rewritable optical data storage. In both application areas the reversible switching between the amorphous and the crystalline state by short current or laser pulses, respectively is used to store data. A key question that has not yet been answered regards the optimum choice of materials for phase change recording. We present a material selection strategy which classifies carefully chosen alloys, being representative for a larger selection of phase change materials, regarding their suitability for non-volatile storage applications. XRD and XRR measurements reveal structural properties of the as-deposited, amorphous and the crystalline state, the corresponding local bond arrangements and the change of film density. Ellipsometry measurements determine the optical contrast of the samples while the temperature dependent resistivity is measured by four point probe experiments. Finally the electrical switching behaviour is tested in nanometer size test cells to validate the full functionality of the chosen materials.

  15. Spectroscopic evaluation of painted layer structural changes induced by gamma radiation in experimental models

    International Nuclear Information System (INIS)

    Manea, Mihaela M.; Moise, Ioan V.; Virgolici, Marian; Negut, Constantin D.; Barbu, Olimpia-Hinamatsuri; Cutrubinis, Mihalis; Fugaru, Viorel; Stanculescu, Ioana R.; Ponta, Corneliu C.

    2012-01-01

    The degradation of cultural heritage objects by insects and microorganisms is an important issue for conservators, art specialists and humankind in general. Gamma irradiation is an efficient method of polychrome wooden artifacts disinfestation. Color changes and other modifications in the physical chemical properties of materials induced by gamma irradiation are feared by cultural heritage responsible committees and they have to be evaluated objectively and precisely. In this paper FTIR and FT-Raman spectroscopy methods were used to investigate the structural changes in some experimental models of tempera paint layers on wood following 11 kGy gamma irradiation at two dose rates. Radiation chemistry depends on the particular pigment, matrix formed by protein, resin (in case of varnished samples) and water presence. For the majority of painted layer in experimental models very small spectral variations were observed. Small changes in the FTIR spectra were observed for the raw sienna experimental model: for the higher dose rate the egg yolk protein oxidation peaks and the CH stretching bands due to lipids degradation products increased. - Highlights: ► Experimental models of tempera paint layers on wood were γ-irradiated at two dose rates. ► Changes induced by γ-irradiation were evaluated by vibrational spectroscopy. ► Minor spectral variations of painted layer were observed. ► Raw sienna FTIR spectra showed little changes of egg yolk and lipids at higher dose rate. ► Gamma irradiation is recommended for disinfection of painted wooden artifacts.

  16. Structural plasticity of the social brain: Differential change after socio-affective and cognitive mental training.

    Science.gov (United States)

    Valk, Sofie L; Bernhardt, Boris C; Trautwein, Fynn-Mathis; Böckler, Anne; Kanske, Philipp; Guizard, Nicolas; Collins, D Louis; Singer, Tania

    2017-10-01

    Although neuroscientific research has revealed experience-dependent brain changes across the life span in sensory, motor, and cognitive domains, plasticity relating to social capacities remains largely unknown. To investigate whether the targeted mental training of different cognitive and social skills can induce specific changes in brain morphology, we collected longitudinal magnetic resonance imaging (MRI) data throughout a 9-month mental training intervention from a large sample of adults between 20 and 55 years of age. By means of various daily mental exercises and weekly instructed group sessions, training protocols specifically addressed three functional domains: (i) mindfulness-based attention and interoception, (ii) socio-affective skills (compassion, dealing with difficult emotions, and prosocial motivation), and (iii) socio-cognitive skills (cognitive perspective-taking on self and others and metacognition). MRI-based cortical thickness analyses, contrasting the different training modules against each other, indicated spatially diverging changes in cortical morphology. Training of present-moment focused attention mostly led to increases in cortical thickness in prefrontal regions, socio-affective training induced plasticity in frontoinsular regions, and socio-cognitive training included change in inferior frontal and lateral temporal cortices. Module-specific structural brain changes correlated with training-induced behavioral improvements in the same individuals in domain-specific measures of attention, compassion, and cognitive perspective-taking, respectively, and overlapped with task-relevant functional networks. Our longitudinal findings indicate structural plasticity in well-known socio-affective and socio-cognitive brain networks in healthy adults based on targeted short daily mental practices. These findings could promote the development of evidence-based mental training interventions in clinical, educational, and corporate settings aimed at

  17. Wood production response to climate change will depend critically on forest composition and structure.

    Science.gov (United States)

    Coomes, David A; Flores, Olivier; Holdaway, Robert; Jucker, Tommaso; Lines, Emily R; Vanderwel, Mark C

    2014-12-01

    Established forests currently function as a major carbon sink, sequestering as woody biomass about 26% of global fossil fuel emissions. Whether forests continue to act as a global sink will depend on many factors, including the response of aboveground wood production (AWP; MgC ha(-1 ) yr(-1) ) to climate change. Here, we explore how AWP in New Zealand's natural forests is likely to change. We start by statistically modelling the present-day growth of 97 199 individual trees within 1070 permanently marked inventory plots as a function of tree size, competitive neighbourhood and climate. We then use these growth models to identify the factors that most influence present-day AWP and to predict responses to medium-term climate change under different assumptions. We find that if the composition and structure of New Zealand's forests were to remain unchanged over the next 30 years, then AWP would increase by 6-23%, primarily as a result of physiological responses to warmer temperatures (with no appreciable effect of changing rainfall). However, if warmth-requiring trees were able to migrate into currently cooler areas and if denser canopies were able to form, then a different AWP response is likely: forests growing in the cool mountain environments would show a 30% increase in AWP, while those in the lowland would hardly respond (on average, -3% when mean annual temperature exceeds 8.0 °C). We conclude that response of wood production to anthropogenic climate change is not only dependent on the physiological responses of individual trees, but is highly contingent on whether forests adjust in composition and structure. © 2014 John Wiley & Sons Ltd.

  18. High-spin states in 136La and possible structure change in the N =79 region

    Science.gov (United States)

    Nishibata, H.; Leguillon, R.; Odahara, A.; Shimoda, T.; Petrache, C. M.; Ito, Y.; Takatsu, J.; Tajiri, K.; Hamatani, N.; Yokoyama, R.; Ideguchi, E.; Watanabe, H.; Wakabayashi, Y.; Yoshinaga, K.; Suzuki, T.; Nishimura, S.; Beaumel, D.; Lehaut, G.; Guinet, D.; Desesquelles, P.; Curien, D.; Higashiyama, K.; Yoshinaga, N.

    2015-05-01

    High-spin states in the odd-odd nucleus 136La, which is located close to the β -stability line, have been investigated in the radioactive-beam-induced fusion-evaporation reaction 124Sn(17N,5 n ). The use of the radioactive beam enabled a highly sensitive and successful search for a new isomer [14+,T1 /2=187 (27 ) ns] in 136La. In the A =130 -140 mass region, no such long-lived isomer has been observed at high spin in odd-odd nuclei. The 136La level scheme was revised, incorporating the 14+ isomer and six new levels. The results were compared with pair-truncated shell model (PTSM) calculations which successfully explain the level structure of the π h11 /2⊗ν h11/2 -1 bands in 132La and 134La. The isomerism of the 14+ state was investigated also by a collective model, the cranked Nilsson-Strutinsky (CNS) model, which explains various high-spin structures in the medium-heavy mass region. It is suggested that a new type of collective structure is induced in the PTSM model by the increase of the number of π g7 /2 pairs, and/or in the CNS model by the configuration change associated with the shape change in 136La.

  19. A study on structural changes in protein by time-division type Laue method

    International Nuclear Information System (INIS)

    Morimoto, Hideki

    1995-01-01

    In order to know the physiological roles of proteins, it is important to investigate the intermediate states of their structural changes. The sizes of proteins are generally several tens angstrom(A). Considering the resolution, only x-ray crystal analysis can be used in practice for the investigation of the mechanism of protein structural changes, though NMR is applicable only for small-sized proteins. However, x-ray analysis is not so suitable for analysis of their intermediate states. Thus, the author paid attention to the time-division type Laue method for the study of hemoglobin (Hb). Laser-flash induces to release carbonmonooxide (CO) from carboxyhemoglobin (Hb(CO) 4 ). Therefore, if an appropriate length of x-ray pulse (∼100 picosec) is available, the processes in the period from cleavage of the bond between a ligand (O 2 , CO or NO) and Hb to recombination of them might be monitored. Using DNA recombination and chemical modification techniques, recombinant Hb, of which T structure is stable was produced. An investigation on the conditions which allow to release CO from the Hb is undertaken using a single crystal of this Hb. The experimental systems applicable to time-division type Laue method are some protein molecules participating in chemical reactions inducible by light absorption, the electron-transfer system excited by light and so on. (M.N.)

  20. Sleep Duration and Age-Related Changes in Brain Structure and Cognitive Performance

    Science.gov (United States)

    Lo, June C.; Loh, Kep Kee; Zheng, Hui; Sim, Sam K.Y.; Chee, Michael W.L.

    2014-01-01

    Study Objectives: To investigate the contribution of sleep duration and quality to age-related changes in brain structure and cognitive performance in relatively healthy older adults. Design: Community-based longitudinal brain and cognitive aging study using a convenience sample. Setting: Participants were studied in a research laboratory. Participants: Relatively healthy adults aged 55 y and older at study commencement. Interventions: N/A. Measurements and Results: Participants underwent magnetic resonance imaging and neuropsychological assessment every 2 y. Subjective assessments of sleep duration and quality and blood samples were obtained. Each hour of reduced sleep duration at baseline augmented the annual expansion rate of the ventricles by 0.59% (P = 0.007) and the annual decline rate in global cognitive performance by 0.67% (P = 0.050) in the subsequent 2 y after controlling for the effects of age, sex, education, and body mass index. In contrast, global sleep quality at baseline did not modulate either brain or cognitive aging. High-sensitivity C-reactive protein, a marker of systemic inflammation, showed no correlation with baseline sleep duration, brain structure, or cognitive performance. Conclusions: In healthy older adults, short sleep duration is associated with greater age-related brain atrophy and cognitive decline. These associations are not associated with elevated inflammatory responses among short sleepers. Citation: Lo JC, Loh KK, Zheng H, Sim SK, Chee MW. Sleep duration and age-related changes in brain structure and cognitive performance. SLEEP 2014;37(7):1171-1178. PMID:25061245

  1. Changes in structural integrity are correlated with motor and functional recovery after post-stroke rehabilitation.

    Science.gov (United States)

    Fan, Yang-teng; Lin, Keh-chung; Liu, Ho-ling; Chen, Yao-liang; Wu, Ching-yi

    2015-01-01

    Diffusion tensor imaging (DTI) studies indicate the structural integrity of the ipsilesional corticospinal tract (CST) and the transcallosal motor tract, which are closely linked to stroke recovery. However, the individual contribution of these 2 fibers on different levels of outcomes remains unclear. Here, we used DTI tractography to investigate whether structural changes of the ipsilesional CST and the transcallosal motor tracts associate with motor and functional recovery after stroke rehabilitation. Ten participants with post-acute stroke underwent the Fugl-Meyer Assessment (FMA), the Wolf Motor Function Test (WMFT), the Functional Independence Measure (FIM), and DTI before and after bilateral robotic training. All participants had marked improvements in motor performance, functional use of the affected arm, and independence in daily activities. Increased fractional anisotropy (FA) in the ipsilesional CST and the transcallosal motor tracts was noted from pre-treatment to the end of treatment. Participants with higher pre-to-post differences in FA values of the transcallosal motor tracts had greater gains in the WMFT and the FIM scores. A greater improvement on the FMA was coupled with increased FA changes along the ipsilesional CST. These findings suggest 2 different structural indicators for post-stroke recovery separately at the impairment-based and function-based levels.

  2. Sample Thickness and Structural Changes in Thermo-Oxidative Degradation of Polybutadiene

    Directory of Open Access Journals (Sweden)

    farshid Ziaee

    2012-12-01

    Full Text Available The thermo-oxidative degradation of two viscous liquid resins of 1,2- poly-butadiene  (1,2-PBD and 1,4- polybutadiene  (1,4-PBD have been studied by differential scanning calorimetry (DSC and thermogravimetry analy-sis  (TGA. To  study  further,  the  effect of flm  thickness on oxidation kinetics was periodically studied by tracing the weight of the samples to make comparison with DSC results at constant temperature of 100°C under atmospheric pressure. Finally, the structural changes of 1,4-PBD were investigated by carbon-13 nuclear magnetic resonance spectroscopy (13C NMR. The results from 13C NMR from 1,4-PBD show that after heat treatment new carbon peaks are obtained for an epoxide carbon at 58.6 ppm, an adjacent methylene carbon of epoxide group at 24.0 ppm and a peroxide methine carbon group at 86.7 ppm. The results from TGA and DSC studies conclude that 1,2-PBD do not age due to its structure. The results from NMR spectroscopy indicate that besides structural changes, increase in mass is due to radical addition to double bond while, epoxide groups are one of major products of thermal oxidation which can be identifed from their 13 C NMR peaks.

  3. Structural Changes of Lumbar Muscles in Non-specific Low Back Pain: A Systematic Review.

    Science.gov (United States)

    Goubert, Dorien; Oosterwijck, Jessica Van; Meeus, Mira; Danneels, Lieven

    2016-01-01

    Lumbar muscle dysfunction due to pain might be related to altered lumbar muscle structure. Macroscopically, muscle degeneration in low back pain (LBP) is characterized by a decrease in cross-sectional area and an increase in fat infiltration in the lumbar paraspinal muscles. In addition microscopic changes, such as changes in fiber distribution, might occur. Inconsistencies in results from different studies make it difficult to draw firm conclusions on which structural changes are present in the different types of non-specific LBP. Insights regarding structural muscle alterations in LBP are, however, important for prevention and treatment of non-specific LBP. The goal of this article is to review which macro- and/or microscopic structural alterations of the lumbar muscles occur in case of non-specific chronic low back pain (CLBP), recurrent low back pain (RLBP), and acute low back pain (ALBP). Systematic review. All selected studies were case-control studies. A systematic literature search was conducted in the databases PubMed and Web of Science. Only full texts of original studies regarding structural alterations (atrophy, fat infiltration, and fiber type distribution) in lumbar muscles of patients with non-specific LBP compared to healthy controls were included. All included articles were scored on methodological quality. Fifteen studies were found eligible after screening title, abstract, and full text for inclusion and exclusion criteria. In CLBP, moderate evidence of atrophy was found in the multifidus; whereas, results in the paraspinal and the erector spinae muscle remain inconclusive. Also moderate evidence occurred in RLBP and ALBP, where no atrophy was shown in any lumbar muscle. Conflicting results were seen in undefined LBP groups. Results concerning fat infiltration were inconsistent in CLBP. On the other hand, there is moderate evidence in RLBP that fat infiltration does not occur, although a larger muscle fat index was found in the erector spinae

  4. A terrestrial lidar assessment of climate change impacts on forest structure

    Science.gov (United States)

    van Aardt, J. A.; Kelbe, D.; Sacca, K.; Giardina, C. P.; Selmants, P. C.; Litton, C. M.; Asner, G. P.

    2016-12-01

    The projected impact of climate change on ecosystems has received much scientific attention, specifically related to geographical species shifts and carbon allocation. This study, however, was undertaken to assess the expected changes in tropical forest structure as a function of changing temperatures. Our study area is a constrained model ecological system and is located on the eastern flank of Mauna Kea Volcano, Hawaii, USA. Nine plots from this closed-canopy, tropical montane wet forest fall along an elevation-based 5.2°C mean annual temperature (MAT) gradient, where multiple other biotic and abiotic factors are held nearly constant. This MAT gradient has been used to assess subtle temperature effects on ecosystem functioning including carbon cycles, but less has been done on the effects of temperature on vegetation structure. We acquired vegetation structural data using a SICK-LMS151 terrestrial laser scanner (905 nm) for full 270x360° coverage. This Compact Biomass Lidar (CBL) was developed by Rochester Institute of Technology and the University of Massachusetts, Boston. Data for each plot along the temperature gradient were collected in a 20 m x 20 m configuration at a 5 m scan spacing. Initial challenges, related to the irregular radial scan pattern and registration of 25 scans per plot, were addressed in order to extract normalized vegetation density metrics and to mitigate occlusion effects, respectively. However, we believe that the CBL scans can be assessed independently, i.e., treating 25 scans/plot as a population sample. We derived height statistics, return density metrics, canopy rugosity, and higher-order metrics in order to describe the differences in vegetation structure, which ultimately will be tied to the elevation-induced temperature range. We hypothesized that, for this MAT gradient (i) vertical vegetation stratification; (ii) diameter distributions; and (iii) aboveground biomass will differ significantly, while more species

  5. The influence of model structure on groundwater recharge rates in climate-change impact studies

    Science.gov (United States)

    Moeck, Christian; Brunner, Philip; Hunkeler, Daniel

    2016-08-01

    Numerous modeling approaches are available to provide insight into the relationship between climate change and groundwater recharge. However, several aspects of how hydrological model choice and structure affect recharge predictions have not been fully explored, unlike the well-established variability of climate model chains—combination of global climate models (GCM) and regional climate models (RCM). Furthermore, the influence on predictions related to subsoil parameterization and the variability of observation data employed during calibration remain unclear. This paper compares and quantifies these different sources of uncertainty in a systematic way. The described numerical experiment is based on a heterogeneous two-dimensional reference model. Four simpler models were calibrated against the output of the reference model, and recharge predictions of both reference and simpler models were compared to evaluate the effect of model structure on climate-change impact studies. The results highlight that model simplification leads to different recharge rates under climate change, especially under extreme conditions, although the different models performed similarly under historical climate conditions. Extreme weather conditions lead to model bias in the predictions and therefore must be considered. Consequently, the chosen calibration strategy is important and, if possible, the calibration data set should include climatic extremes in order to minimise model bias introduced by the calibration. The results strongly suggest that ensembles of climate projections should be coupled with ensembles of hydrogeological models to produce credible predictions of future recharge and with the associated uncertainties.

  6. Irradiation-induced structure and property changes in tokamak plasma-facing, carbon-carbon composites

    International Nuclear Information System (INIS)

    Burchell, T.D.

    1994-01-01

    Carbon-carbon composites are an attractive choice for fusion reactor plasma-facing components because of their low atomic number, superior thermal shock resistance, and low neutron activation. Next generation plasma fusion reactors, such as the International Thermonuclear Experimental Reactor (ITER), will require advanced carbon-carbon composite materials possessing high thermal conductivity to manage the anticipated severe heat loads. Moreover, ignition machines such as ITER will produce large neutron fluxes. Consequently, the influence of neutron damage on the structure and properties of carbon-carbon composite materials must be evaluated. Data from two irradiation experiments are reported and discussed here. Carbon-carbon composite materials were irradiated in target capsules in the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL). A peak damage dose of 4.7 displacements per atom (dpa) at 600 degree C was attained. The carbon materials irradiated included uni-directional, two-directional, and three-directional carbon-carbon composites. Dimensional changes are reported for the composite materials and are related to single crystal dimensional changes through fiber and composite structural models. Moreover, the irradiation-induced dimensional changes are reported and discussed in terms of their architecture, fiber type, and graphitization temperature. The effect of neutron irradiation on thermal conductivity of two three-directional, carbon-carbon composites is reported and the recovery of thermal conductivity due to thermal annealing is discussed

  7. Changes in glycosaminoglycan structure on differentiation of human embryonic stem cells towards mesoderm and endoderm lineages.

    Science.gov (United States)

    Gasimli, Leyla; Hickey, Anne Marie; Yang, Bo; Li, Guoyun; dela Rosa, Mitche; Nairn, Alison V; Kulik, Michael J; Dordick, Jonathan S; Moremen, Kelley W; Dalton, Stephen; Linhardt, Robert J

    2014-06-01

    Proteoglycans are found on the cell surface and in the extracellular matrix, and serve as prime sites for interaction with signaling molecules. Proteoglycans help regulate pathways that control stem cell fate, and therefore represent an excellent tool to manipulate these pathways. Despite their importance, there is a dearth of data linking glycosaminoglycan structure within proteoglycans with stem cell differentiation. Human embryonic stem cell line WA09 (H9) was differentiated into early mesoderm and endoderm lineages, and the glycosaminoglycanomic changes accompanying these transitions were studied using transcript analysis, immunoblotting, immunofluorescence and disaccharide analysis. Pluripotent H9 cell lumican had no glycosaminoglycan chains whereas in splanchnic mesoderm lumican was glycosaminoglycanated. H9 cells have primarily non-sulfated heparan sulfate chains. On differentiation towards splanchnic mesoderm and hepatic lineages N-sulfo group content increases. Differences in transcript expression of NDST1, HS6ST2 and HS6ST3, three heparan sulfate biosynthetic enzymes, within splanchnic mesoderm cells compared to H9 cells correlate to changes in glycosaminoglycan structure. Differentiation of embryonic stem cells markedly changes the proteoglycanome. The glycosaminoglycan biosynthetic pathway is complex and highly regulated, and therefore, understanding the details of this pathway should enable better control with the aim of directing stem cell differentiation. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Urban Land Expansion and Structural Change in the Yangtze River Delta, China

    Directory of Open Access Journals (Sweden)

    Jinlong Gao

    2015-07-01

    Full Text Available Urban development in China has attracted considerable scholarly attention. However, more work is still needed to examine and understand the mechanisms of urban land expansion, especially within the context of globalization/marketization, decentralization and urbanization. This paper analyzes urban land expansion and structural changes in the Yangtze River Delta (YRD. We find that cities in the YRD are experiencing urban land expansion mainly characterized by the growth of residential and industrial land. The dominant characteristics of urban land expansion in cities have also varied within different development and administrative levels. Based on our conceptual framework, we have used multi-models to investigate the driving forces of urban land expansion and structural changes in the YRD. The results reveal that six influencing factors—foreign direct investment (FDI, labor, government competition, institution, population, and job-housing relations—facilitate land use change in the economic transition process. However, their impacts differ in cities in different geographical locations, as well as with different administrative levels. Finally, this paper discusses policies to promote sustainable urban land use in the YRD.

  9. Effect of ionizing radiation on structural changes of energy nutrients in feeds

    International Nuclear Information System (INIS)

    Dvorak, J.; Smid, K.; Hrusovsky, J.

    1985-01-01

    For the purpose of testing the effect of ionizing radiation, feeds for dogs (meat feed mixture VETACAN and loose feed mixture VETAVIT) irradiated with 60 Co at a dose of 25 kGy/kg were studied for 60 days. It was found that the total volume of energetic and non-energetic nutrients did not change. Qualitative structure, however, displayed a significant, on the average 35% disintegration of essential amino acids, a decrease in proteins and increase in free ammoniacal bases. A significant oxidation effect of radiation is exerted on the decomposition of fats with a release of free fatty acids from the glycerol bond in a process similar to racidification (from 13.3 - 20.88 - 37.10 mg/g in meat mixture, from 103.1 - 130.04 - 135.04 mg/g in loose mixture). A certain disintegration of nutrients, only within the limits of significance, occurred also in the saccharide proportion of the loose feed mixture (acidity of water extract 348.8 - 403.99 -436.60 mg/100 g). It was proved that radiosterilization reliably secured microbiological and mycological sanitation of feeds and caused no sensory changes noticeable by human senses. It follows from the results that ionizing radiation had a pronounced antimicrobial and antimycotic effect. However, it caused significant structural changes in energetic nutrients in the feeds of animal as well as of vegetable origin. (author)

  10. Analysis of structural changes in permanent waved human hair using Raman spectroscopy.

    Science.gov (United States)

    Kuzuhara, Akio

    2007-02-15

    To investigate the mechanism leading to the reduction in tensile strength of permanent waved human hair, the structure of cross-sections at various depths of permanent waved white human hair was directly analyzed without isolating the cuticle and cortex, using Raman spectroscopy. The beta-sheet and/or random coil content (beta/R) and the Amide III(unordered) band intensity existing throughout the cortex region of virgin white human hair remarkably increased, while the alpha-helix (alpha) content slightly decreased by performing the permanent waving treatment. This suggests a secondary structural change from the alpha-helix form to the random coil form in the proteins existing in the microfibril of the cortex region. On the other hand, the S-S band intensity existing in the matrix of the cortex region almost did not change, despite the reduction in the tensile strength of the white human hair following the permanent waving treatment. Moreover, the transmission electron microscope observation shows that the macrofibril (the microfibril and matrix) existing in the cortex region of the virgin white human hair was remarkably disturbed, while the cuticle region was almost unchanged by performing the permanent waving treatment. From these experiments, the authors concluded that some of proteins existing in the cortex region (the microfibril and matrix) of the virgin white human hair were changed, thereby leading to the remarkable reduction in the tensile strength of the white human hair after the permanent waving treatment. 2006 Wiley Periodicals, Inc.

  11. Age structure, changing demography and effective population size in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Palstra, Friso P; O'Connell, Michael F; Ruzzante, Daniel E

    2009-08-01

    Effective population size (N(e)) is a central evolutionary concept, but its genetic estimation can be significantly complicated by age structure. Here we investigate N(e) in Atlantic salmon (Salmo salar) populations that have undergone changes in demography and population dynamics, applying four different genetic estimators. For this purpose we use genetic data (14 microsatellite markers) from archived scale samples collected between 1951 and 2004. Through life table simulations we assess the genetic consequences of life history variation on N(e). Although variation in reproductive contribution by mature parr affects age structure, we find that its effect on N(e) estimation may be relatively minor. A comparison of estimator models suggests that even low iteroparity may upwardly bias N(e) estimates when ignored (semelparity assumed) and should thus empirically be accounted for. Our results indicate that N(e) may have changed over time in relatively small populations, but otherwise remained stable. Our ability to detect changes in N(e) in larger populations was, however, likely hindered by sampling limitations. An evaluation of N(e) estimates in a demographic context suggests that life history diversity, density-dependent factors, and metapopulation dynamics may all affect the genetic stability of these populations.

  12. Irradiation-induced structure and property changes in tokamak plasma-facing, carbon-carbon composites

    Science.gov (United States)

    Burchell, T. D.

    Carbon-carbon composites are an attractive choice for fusion reactor plasma-facing components because of their low atomic number, superior thermal shock resistance, and low neutron activation. Next generation plasma fusion reactors, such as the International Thermonuclear Experimental Reactor (ITER), will require advanced carbon-carbon composite materials possessing high thermal conductivity to manage the anticipated severe heat loads. Moreover, ignition machines such as ITER will produce large neutron fluxes. Consequently, the influence of neutron damage on the structure and properties of carbon-carbon composite materials must be evaluated. Data from two irradiation experiments are reported and discussed here. Carbon-carbon composite materials were irradiated in target capsules in the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL). A peak damage dose of 4.7 displacements per atom (dpa) at 600 C was attained. The carbon materials irradiated included unidirectional, two-directional, and three-directional carbon-carbon composites. Dimensional changes are reported for the composite materials and are related to single crystal dimensional changes through fiber and composite structural models. Moreover, the irradiation-induced dimensional changes are reported and discussed in terms of their architecture, fiber type, and graphitization temperature. The effect of neutron irradiation on thermal conductivity of two three-directional, carbon-carbon composites is reported and the recovery of thermal conductivity due to thermal annealing is discussed.

  13. A quantitative measure of electrostatic perturbation in holo and apo enzymes induced by structural changes.

    Directory of Open Access Journals (Sweden)

    Sandeep Chakraborty

    Full Text Available Biological pathways are subject to subtle manipulations that achieve a wide range of functional variation in differing physiological niches. In many instances, changes in the structure of an enzyme on ligand binding germinate electrostatic perturbations that form the basis of its changed catalytic or transcriptional efficiency. Computational methods that seek to gain insights into the electrostatic changes in enzymes require expertise to setup and computing prowess. In the current work, we present a fast, easy and reliable methodology to compute electrostatic perturbations induced by ligand binding (MEPP. The theoretical foundation of MEPP is the conserved electrostatic potential difference (EPD in cognate pairs of active site residues in proteins with the same functionality. Previously, this invariance has been used to unravel promiscuous serine protease and metallo-β-lactamase scaffolds in alkaline phosphatases. Given that a similarity in EPD is significant, we expect differences in the EPD to be significant too. MEPP identifies residues or domains that undergo significant electrostatic perturbations, and also enumerates residue pairs that undergo significant polarity change. The gain in a certain polarity of a residue with respect to neighboring residues, or the reversal of polarity between two residues might indicate a change in the preferred ligand. The methodology of MEPP has been demonstrated on several enzymes that employ varying mechanisms to perform their roles. For example, we have attributed the change in polarity in residue pairs to be responsible for the loss of metal ion binding in fructose 1,6-bisphosphatases, and corroborated the pre-organized state of the active site of the enzyme with respect to functionally relevant changes in electric fields in ketosteroid isomerases.

  14. Electronic structure and spectroscopy of nucleic acid bases: Ionization energies, ionization-induced structural changes, and photoelectron spectra

    Energy Technology Data Exchange (ETDEWEB)

    Bravaya, Ksenia B.; Kostko, Oleg; Dolgikh, Stanislav; Landau, Arie; Ahmed, Musahid; Krylov, Anna I.

    2010-08-02

    We report high-level ab initio calculations and single-photon ionization mass spectrometry study of ionization of adenine (A), thymine (T), cytosine (C) and guanine (G). For thymine and adenine, only the lowest-energy tautomers were considered, whereas for cytosine and guanine we characterized five lowest-energy tautomeric forms. The first adiabatic and several vertical ionization energies were computed using equation-of-motion coupled-cluster method for ionization potentials with single and double substitutions. Equilibrium structures of the cationic ground states were characterized by DFT with the {omega}B97X-D functional. The ionization-induced geometry changes of the bases are consistent with the shapes of the corresponding molecular orbitals. For the lowest-energy tautomers, the magnitude of the structural relaxation decreases in the following series G > C > A > T, the respective relaxation energies being 0.41, 0.32, 0.25 and 0.20 eV. The computed adiabatic ionization energies (8.13, 8.89, 8.51-8.67 and 7.75-7.87 eV for A,T,C and G, respectively) agree well with the onsets of the photoionization efficiency (PIE) curves (8.20 {+-} 0.05, 8.95 {+-} 0.05, 8.60 {+-} 0.05 and 7.75 {+-} 0.05 eV). Vibrational progressions for the S{sub 0}-D{sub 0} vibronic bands computed within double-harmonic approximation with Duschinsky rotations are compared with previously reported experimental photoelectron spectra.

  15. Changes in the Bacterial Community Structure of Remediated Anthracene-Contaminated Soils.

    Directory of Open Access Journals (Sweden)

    Laura Delgado-Balbuena

    Full Text Available Mixing soil or adding earthworms (Eisenia fetida (Savigny, 1826 accelerated the removal of anthracene, a polycyclic aromatic hydrocarbon, from a pasture and an arable soil, while a non-ionic surfactant (Surfynol® 485 inhibited the removal of the contaminant compared to the untreated soil. It was unclear if the treatments affected the soil bacterial community and consequently the removal of anthracene. Therefore, the bacterial community structure was monitored by means of 454 pyrosequencing of the 16S rRNA gene in the pasture and arable soil mixed weekly, amended with Surfynol® 485, E. fetida or organic material that served as food for the earthworms for 56 days. In both soils, the removal of anthracene was in the order: mixing soil weekly (100% > earthworms applied (92% > organic material applied (77% > untreated soil (57% > surfactant applied (34% after 56 days. There was no clear link between removal of anthracene from soil and changes in the bacterial community structure. On the one hand, application of earthworms removed most of the contaminant from the arable soil and had a strong effect on the bacterial community structure, i.e. a decrease in the relative abundance of the Acidobacteria, Chloroflexi and Gemmatimonadetes, and an increase in that of the Proteobacteria compared to the unamended soil. Mixing the soil weekly removed all anthracene from the arable soil, but had little or no effect on the bacterial community structure. On the other hand, application of the surfactant inhibited the removal of anthracene from the arable soil compared to the untreated soil, but had a strong effect on the bacterial community structure, i.e. a decrease in the relative abundance of Cytophagia (Bacteroidetes, Chloroflexi, Gemmatimonadetes and Planctomycetes and an increase in that of the Flavobacteria (Bacteroidetes and Proteobacteria. Additionally, the removal of anthracene was similar in the different treatments of both the arable and pasture soil

  16. Changes in the Bacterial Community Structure of Remediated Anthracene-Contaminated Soils

    Science.gov (United States)

    Delgado-Balbuena, Laura; Bello-López, Juan M.; Navarro-Noya, Yendi E.; Rodríguez-Valentín, Analine; Luna-Guido, Marco L.; Dendooven, Luc

    2016-01-01

    Mixing soil or adding earthworms (Eisenia fetida (Savigny, 1826)) accelerated the removal of anthracene, a polycyclic aromatic hydrocarbon, from a pasture and an arable soil, while a non-ionic surfactant (Surfynol® 485) inhibited the removal of the contaminant compared to the untreated soil. It was unclear if the treatments affected the soil bacterial community and consequently the removal of anthracene. Therefore, the bacterial community structure was monitored by means of 454 pyrosequencing of the 16S rRNA gene in the pasture and arable soil mixed weekly, amended with Surfynol® 485, E. fetida or organic material that served as food for the earthworms for 56 days. In both soils, the removal of anthracene was in the order: mixing soil weekly (100%) > earthworms applied (92%) > organic material applied (77%) > untreated soil (57%) > surfactant applied (34%) after 56 days. There was no clear link between removal of anthracene from soil and changes in the bacterial community structure. On the one hand, application of earthworms removed most of the contaminant from the arable soil and had a strong effect on the bacterial community structure, i.e. a decrease in the relative abundance of the Acidobacteria, Chloroflexi and Gemmatimonadetes, and an increase in that of the Proteobacteria compared to the unamended soil. Mixing the soil weekly removed all anthracene from the arable soil, but had little or no effect on the bacterial community structure. On the other hand, application of the surfactant inhibited the removal of anthracene from the arable soil compared to the untreated soil, but had a strong effect on the bacterial community structure, i.e. a decrease in the relative abundance of Cytophagia (Bacteroidetes), Chloroflexi, Gemmatimonadetes and Planctomycetes and an increase in that of the Flavobacteria (Bacteroidetes) and Proteobacteria. Additionally, the removal of anthracene was similar in the different treatments of both the arable and pasture soil, but the

  17. Nitridation of one-dimensional tungsten oxide nanostructures: Changes in structure and photoactivity

    KAUST Repository

    Varga, Tamás

    2017-10-12

    In the search for stable, visible light active photoelectrodes, hydrothermally synthesized tungsten oxide nanowires were modified via nitrogen incorporation into their structure. To this end, nanowires were heat-treated in ammonia/nitrogen atmosphere at different temperatures. This procedure caused transitions in their structure that were investigated along with the photoelectrochemical properties of the samples. Results were subsequently compared to the reference samples treated in inert nitrogen atmosphere. Morphological changes and structural transitions were followed by transmission and scanning electron microscopy and X-ray diffraction. Bandgap energies were determined from the UV–vis spectra of the materials, while photoelectrochemical properties were tested by linear sweep photovoltammetry and electrochemical impedance spectroscopy. Pristine tungsten oxide nanowires were first transformed into tungsten oxynitride and then tungsten nitride during high-temperature calcination in ammonia atmosphere. Electron microscopic investigation revealed that, along with phase transition, the initial fibrous morphology gradually converted into nanosheets. Simultaneously, bandgap energies significantly decreased in the calcination process, too. Photoelectrochemical measurements demonstrated that photoactivity in the treated samples was not improved by the decrease of the bandgap. This behavior might be explained with the deterioration of charge carrier transport properties of the materials due to the increased number of structural defects (acting as trap states), and current ongoing work aims to verify this notion.

  18. Changes in the Structure of a Nigerian Soil under Different Land Management Practices

    Directory of Open Access Journals (Sweden)

    Joshua Olalekan Ogunwole

    2015-06-01

    Full Text Available Quantification of soil physical quality (SPQ and pore size distribution (PSD can assist understanding of how changes in land management practices influence dynamics of soil structure, and this understanding could greatly improve the predictability of soil physical behavior and crop yield. The objectives of this study were to measure the SPQ index under two different land management practices (the continuous arable cropping system and natural bush fallow system, and contrast the effects of these practices on the structure of PSD using soil water retention data. Soil water retention curves obtained from a pressure chamber were fitted to van Genuchten’s equation, setting m (= 1-1/n. Although values for soil bulk density were high, soils under the continuous arable cropping system had good SPQ, and maintained the capacity to support root development. However, soils under the natural bush fallow system had a worse structure than the continuous arable system, with restrictions in available water capacity. These two management systems had different PSDs. Results showed the inferiority of the natural bush fallow system with no traffic restriction (which is the common practice in relation to the continuous arable cropping system in regard to physical quality and structure.

  19. Change in pore structure of coals by activation with KOH; KOH fukatsushita sekitan no saiko kozo

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, K.; Yoshizawa, N.; Ishikawa, E.; Kobayashi, M.; Toda, Y.; Yamada, Y.; Shiraishi, M. [National Institute for Resources and Environment, Tsukuba (Japan)

    1996-10-28

    Three typical Japanese coals of non-coking coal, coking coal and anthracite were heat-treated with KOH, and change in their pore structure was examined by absorption of N2, X-ray diffraction and TEM observation. In addition, the relation between a coal rank and pore structure was also studied by absorption experiment of N2. In experiment, the mixture of coal and KOH in a nickel holder was heat-treated in N2 gas flow at heating rate of 2{degree}C/min, and held at a fixed temperature for one hour. To clarify the pore structure, N2 absorption isotherms were measured at -196{degree}C under nearly 76cmHg using a commercially available full-automatic absorption measurement equipment. Based on the X-ray diffraction and TEM observation results on activated coals, the relation between the N2 absorption and pore structure was studied. The results are summarized as follows: (1) The yield and absorption ability of coals increase with a coal rank, (2) The specific surface area of coals reaches its peak at 800{degree}C in activation temperature regardless of a coal rank, and (3) The activation behavior of coals is dependent on a coal rank. 5 refs., 7 figs., 1 tab.

  20. Structural and functional connectivity changes in the brain associated with shyness but not with social anxiety.

    Science.gov (United States)

    Yang, Xun; Kendrick, Keith Maurice; Wu, Qizhu; Chen, Taolin; Lama, Sunima; Cheng, Bochao; Li, Shiguang; Huang, Xiaoqi; Gong, Qiyong

    2013-01-01

    Shyness and social anxiety are correlated to some extent and both are associated with hyper-responsivity to social stimuli in the frontal cortex and limbic system. However to date no studies have investigated whether common structural and functional connectivity differences in the brain may contribute to these traits. We addressed this issue in a cohort of 61 healthy adult subjects. Subjects were first assessed for their levels of shyness (Cheek and Buss Shyness scale) and social anxiety (Liebowitz Social Anxiety scale) and trait anxiety. They were then given MRI scans and voxel-based morphometry and seed-based, resting-state functional connectivity analysis investigated correlations with shyness and anxiety scores. Shyness scores were positively correlated with gray matter density in the cerebellum, bilateral superior temporal gyri and parahippocampal gyri and right insula. Functional connectivity correlations with shyness were found between the superior temporal gyrus, parahippocampal gyrus and the frontal gyri, between the insula and precentral gyrus and inferior parietal lobule, and between the cerebellum and precuneus. Additional correlations were found for amygdala connectivity with the medial frontal gyrus, superior frontal gyrus and inferior parietal lobule, despite the absence of any structural correlation. By contrast no structural or functional connectivity measures correlated with social or trait anxiety. Our findings show that shyness is specifically associated with structural and functional connectivity changes in cortical and limbic regions involved with processing social stimuli. These associations are not found with social or trait anxiety in healthy subjects despite some behavioral correlations with shyness.

  1. Structural and functional connectivity changes in the brain associated with shyness but not with social anxiety.

    Directory of Open Access Journals (Sweden)

    Xun Yang

    Full Text Available Shyness and social anxiety are correlated to some extent and both are associated with hyper-responsivity to social stimuli in the frontal cortex and limbic system. However to date no studies have investigated whether common structural and functional connectivity differences in the brain may contribute to these traits. We addressed this issue in a cohort of 61 healthy adult subjects. Subjects were first assessed for their levels of shyness (Cheek and Buss Shyness scale and social anxiety (Liebowitz Social Anxiety scale and trait anxiety. They were then given MRI scans and voxel-based morphometry and seed-based, resting-state functional connectivity analysis investigated correlations with shyness and anxiety scores. Shyness scores were positively correlated with gray matter density in the cerebellum, bilateral superior temporal gyri and parahippocampal gyri and right insula. Functional connectivity correlations with shyness were found between the superior temporal gyrus, parahippocampal gyrus and the frontal gyri, between the insula and precentral gyrus and inferior parietal lobule, and between the cerebellum and precuneus. Additional correlations were found for amygdala connectivity with the medial frontal gyrus, superior frontal gyrus and inferior parietal lobule, despite the absence of any structural correlation. By contrast no structural or functional connectivity measures correlated with social or trait anxiety. Our findings show that shyness is specifically associated with structural and functional connectivity changes in cortical and limbic regions involved with processing social stimuli. These associations are not found with social or trait anxiety in healthy subjects despite some behavioral correlations with shyness.

  2. Interactive 3D visualization of structural changes in the brain of a person with corticobasal syndrome

    Directory of Open Access Journals (Sweden)

    Claudia eHänel

    2014-05-01

    Full Text Available The visualization of the progression of brain tissue loss, which occurs in neurodegenerative diseases like corticobasal syndrome (CBS, is an important prerequisite to understand the course and the causes of this neurodegenerative disorder. Common workflows for visual analysis are often based on single 2D sections since in 3D visualizations more internally situated structures may be occluded by structures near the surface. The reduction of dimensions from 3D to 2D allows for an holistic view onto internal and external structures, but results in a loss of spatial information. Here, we present an application with two 3D visualization designs to resolve these challenges. First, in addition to the volume changes, the semi-transparent anatomy is displayed with an anatomical section and cortical areas for spatial orientation. Second, the principle of importance-driven volume rendering is adapted to give an unrestricted line-of-sight to relevant structures by means of a frustum-like cutout. To strengthen the benefits of the 3D visualization, we decided to provide the application next to standard desktop environments in immersive virtual environments with stereoscopic viewing as well. This improves the depth perception in general and in particular for the second design. Thus, the application presented in this work allows for aneasily comprehensible visual analysis of the extent of brain degeneration and the corresponding affected regions.

  3. A Cell-Mimicking Structure Converting Analog Volume Changes to Digital Colorimetric Output with Molecular Selectivity.

    Science.gov (United States)

    Zhang, Zijie; Liu, Yibo; Zhang, Xiaohan; Liu, Juewen

    2017-12-13

    We herein report a three-component cell-mimicking structure with a peroxidase-like iron oxide nanozyme as the nucleus, a molecularly imprinted hydrogel shell as cytoplasm, and a lipid bilayer membrane. The structure was characterized by cryo and negative stain TEM and also by a calcein leakage test. By introducing charged monomers, the gel shell can swell or shrink in response to salt concentration. By lowering the salt concentration, the gradual "analog" gel volume change was reflected in a switch-like "digital" colorimetric output by the burst of membrane and oxidation of substrates such as 3,3',5,5'-tetramethylbenzidine (TMB). Controlled access was also achieved by using melittin to insert channels cross the membrane, and selective molecular transport was realized by the molecularly imprinted gel. The functions of each component are coupled, and this sophisticated tripartite structure provides a new platform for modular design of new materials. Our cell-mimicking structure is functional and it is complementary to the current protocell work that aims to understand the origin of life.

  4. The structural changes of the food industry in the European Union

    DEFF Research Database (Denmark)

    Hajderllari, Luljeta; Karantininis, Konstantinos

    This paper studies the structural changes of food industry in the EU-27. We first provide a detailed description of the relative importance of the various sectors in the food industry. The structure is studied by calculating Gini coefficients for the EU members with regard to food industry. We find...... that the food industry is one of the most important components of the manufacturing sectors in terms of turnover and employment. Enterprises in the EU are relatively large in terms of turnover but small in the number of enterprises with the dairy and meat sectors being the most important branches of the food...... industry regarding the share of turnover, employment and enterprises. During the eight years 2000-2007, the Gini coefficient of the food industry in the EU is very close to 1, indicating a high degree of concentration....

  5. Invertebrate metacommunity structure and dynamics in an andean glacial stream network facing climate change

    DEFF Research Database (Denmark)

    Cauvy-Fraunié, Sophie; Espinosa, Rodrigo; Andino, Patricio

    2015-01-01

    Under the ongoing climate change, understanding the mechanisms structuring the spatial distribution of aquatic species in glacial stream networks is of critical importance to predict the response of aquatic biodiversity in the face of glacier melting. In this study, we propose to use metacommunity.......g., overland, watercourse, and downstream directional dispersal) in organizing the aquatic metacommunity. Results revealed that both environmental and spatial variables significantly explained community variation among sites. Among all environmental variables, the glacial influence component best explained...... macroinvertebrate metacommunity structure in many ways. Indeed, the harsh environmental conditions characterizing glacial influence not only constitute the primary environmental filter but also, limit water-borne macroinvertebrate dispersal. Therefore, glacier runoff acts as an aquatic dispersal barrier, isolating...

  6. The Great Recession and Its Aftermath: What Role for Structural Changes?

    Directory of Open Access Journals (Sweden)

    Jesse Rothstein

    2017-04-01

    Full Text Available The years since the 2009 end of the Great Recession have been disastrous for many workers, particularly those with low human capital or other disadvantages. One explanation attributes this to deficient aggregate labor demand, to which marginal workers are more sensitive. A second attributes it to structural changes. Cyclical explanations imply that if aggregate labor demand is increased then many of the post-2009 patterns will revert to their pre-recession trends. Structural explanations suggest recent experience is the “new normal.” This paper reviews data since 2007 for evidence. I examine wage trends to measure the relative importance of supply and demand. I find little wage pressure before 2015, pointing to demand as the binding constraint. The most recent data show some signs of tightness, but still substantial slack.

  7. RNAsnp: efficient detection of local RNA secondary structure changes induced by SNPs

    DEFF Research Database (Denmark)

    Radhakrishnan, Sabarinathan; Tafer, Hakim; Seemann, Ernst Stefan

    2013-01-01

    into structural effects of SNPs. The global measures employed so far suffer from limited accuracy of folding programs on large RNAs and are computationally too demanding for genome-wide applications. Here, we present a strategy that focuses on the local regions of maximal structural change between mutant and wild......-type. These local regions are approximated in a "screening mode" that is intended for genome-wide applications. Furthermore, localized regions are identified as those with maximal discrepancy. The mutation effects are quantified in terms of empirical P values. To this end, the RNAsnp software uses extensive...... precomputed tables of the distribution of SNP effects as function of length and GC content. RNAsnp thus achieves both a noise reduction and speed-up of several orders of magnitude over shuffling-based approaches. On a data set comprising 501 SNPs associated with human-inherited diseases, we predict 54 to have...

  8. Navigation-related structural change in the hippocampi of taxi drivers.

    Science.gov (United States)

    Maguire, E A; Gadian, D G; Johnsrude, I S; Good, C D; Ashburner, J; Frackowiak, R S; Frith, C D

    2000-04-11

    Structural MRIs of the brains of humans with extensive navigation experience, licensed London taxi drivers, were analyzed and compared with those of control subjects who did not drive taxis. The posterior hippocampi of taxi drivers were significantly larger relative to those of control subjects. A more anterior hippocampal region was larger in control subjects than in taxi drivers. Hippocampal volume correlated with the amount of time spent as a taxi driver (positively in the posterior and negatively in the anterior hippocampus). These data are in accordance with the idea that the posterior hippocampus stores a spatial representation of the environment and can expand regionally to accommodate elaboration of this representation in people with a high dependence on navigational skills. It seems that there is a capacity for local plastic change in the structure of the healthy adult human brain in response to environmental demands.

  9. Phase change predictions for liquid fuel in contact with steel structure using the heat conduction equation

    International Nuclear Information System (INIS)

    Brear, D.J.

    1998-01-01

    When liquid fuel makes contact with steel structure the liquid can freeze as a crust and the structure can melt at the surface. The melting and freezing processes that occur can influence the mode of fuel freezing and hence fuel relocation. Furthermore the temperature gradients established in the fuel and steel phases determine the rate at which heat is transferred from fuel to steel. In this memo the 1-D transient heat conduction equations are applied to the case of initially liquid UO 2 brought into contact with solid steel using up-to-date materials properties. The solutions predict criteria for fuel crust formation and steel melting and provide a simple algorithm to determine the interface temperature when one or both of the materials is undergoing phase change. The predicted steel melting criterion is compared with available experimental results. (author)

  10. Phase change predictions for liquid fuel in contact with steel structure using the heat conduction equation

    Energy Technology Data Exchange (ETDEWEB)

    Brear, D.J. [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1998-01-01

    When liquid fuel makes contact with steel structure the liquid can freeze as a crust and the structure can melt at the surface. The melting and freezing processes that occur can influence the mode of fuel freezing and hence fuel relocation. Furthermore the temperature gradients established in the fuel and steel phases determine the rate at which heat is transferred from fuel to steel. In this memo the 1-D transient heat conduction equations are applied to the case of initially liquid UO{sub 2} brought into contact with solid steel using up-to-date materials properties. The solutions predict criteria for fuel crust formation and steel melting and provide a simple algorithm to determine the interface temperature when one or both of the materials is undergoing phase change. The predicted steel melting criterion is compared with available experimental results. (author)

  11. Atomic resolution of structural changes in elastic crystals of copper(II) acetylacetonate

    Science.gov (United States)

    Worthy, Anna; Grosjean, Arnaud; Pfrunder, Michael C.; Xu, Yanan; Yan, Cheng; Edwards, Grant; Clegg, Jack K.; McMurtrie, John C.

    2018-01-01

    Single crystals are typically brittle, inelastic materials. Such mechanical responses limit their use in practical applications, particularly in flexible electronics and optical devices. Here we describe single crystals of a well-known coordination compound—copper(II) acetylacetonate—that are flexible enough to be reversibly tied into a knot. Mechanical measurements indicate that the crystals exhibit an elasticity similar to that of soft materials such as nylon, and thus display properties normally associated with both hard and soft matter. Using microfocused synchrotron radiation, we mapped the changes in crystal structure that occur on bending, and determined the mechanism that allows this flexibility with atomic precision. We show that, under strain, the molecules in the crystal reversibly rotate, and thus reorganize to allow the mechanical compression and expansion required for elasticity and still maintain the integrity of the crystal structure.

  12. The dynamic relationship between structural change and CO2 emissions in Malaysia: a cointegrating approach.

    Science.gov (United States)

    Ali, Wajahat; Abdullah, Azrai; Azam, Muhammad

    2017-05-01

    The current study investigates the dynamic relationship between structural changes, real GDP per capita, energy consumption, trade openness, population density, and carbon dioxide (CO 2 ) emissions within the EKC framework over a period 1971-2013. The study used the autoregressive distributed lagged (ARDL) approach to investigate the long-run relationship between the selected variables. The study also employed the dynamic ordinary least squared (DOLS) technique to obtain the robust long-run estimates. Moreover, the causal relationship between the variables is explored using the VECM Granger causality test. Empirical results reveal a negative relationship between structural change and CO 2 emissions in the long run. The results indicate a positive relationship between energy consumption, trade openness, and CO 2 emissions. The study applied the turning point formula of Itkonen (2012) rather than the conventional formula of the turning point. The empirical estimates of the study do not support the presence of the EKC relationship between income and CO 2 emissions. The Granger causality test indicates the presence of long-run bidirectional causality between energy consumption, structural change, and CO 2 emissions in the long run. Economic growth, openness to trade, and population density unidirectionally cause CO 2 emissions. These results suggest that the government should focus more on information-based services rather than energy-intensive manufacturing activities. The feedback relationship between energy consumption and CO 2 emissions suggests that there is an ominous need to refurbish the energy-related policy reforms to ensure the installations of some energy-efficient modern technologies.

  13. The effect of structural changes on magnetic permeability of amorphous powder Ni80Co20

    Directory of Open Access Journals (Sweden)

    Maričić A.

    2008-01-01

    Full Text Available The structural changes of Ni80Co20 amorphous powder were tested during heating. The alloy was obtained by electrolysis from ammonia solution sulfate of cobalt and nickel on the titanium cathode. The differential scanning calorimetry (DSC method was used to detect that the crystallization process of powder occurred in two stages with crystallization peaks temperatures of the first stage at 690 K and of the second stage at 790 K. The effect of structural relaxation and crystallization of powder on magnetic properties was predicted by measurement of the relative magnetic permeability change in isothermal and nonisothermal conditions. On the basis of the time change of relative magnetic permeability at a defined temperature in the temperature range of the first and second crystallization peak on the thermogram, the kinetics of crystallization was defined. It was predicted, that in the initial time interval, in the range of the first crystallization peak, the rate of crystallization is determined by the rate of nucleation of the amorphous part of the powder. However, in the second time interval, the crystallization rate is determined by the rate of diffusion. In the range of the second peak, in the beginning the rate of crystal growth is determined by activation energy of the atom pass from smaller to bigger crystal grain. In second time interval, the rate of crystal grain growth is determined by the diffusion rate of atoms to the location of integration into bigger crystal grains. For all processes which determine the rate of crystallization in temperature ranges of both crystallization peaks, the Arrhenius temperature dependence of rate for those processes is obtained. The relative magnetic permeability of crystallized powder at 873 K, is smaller for about 30 % than the relative magnetic permeability of fresh powder at room temperature. However, structurally relaxed powder at 573 K has an about 22 % larger magnetic permeability than the same fresh

  14. Pressure-induced structural change in liquid GeI4.

    Science.gov (United States)

    Fuchizaki, Kazuhiro; Nishimura, Hironori; Hase, Takaki; Saitoh, Hiroyuki

    2017-12-13

    The similarity in the shape of the melting curve of GeI4 to that of SnI4 suggests that a liquid-liquid transition as observed in liquid SnI4 is also expected to occur in liquid GeI4. Because the slope of the melting curve of GeI4 abruptly changes at around 3 GPa, in situ synchrotron diffraction measurements were conducted to examine closely the structural changes upon compression at around 3 GPa. The reduced radial distribution functions of the high- and low-pressure liquid states of GeI4 share the same feature inherent in the high-pressure (high-density) and low-pressure (low-density) radial distribution functions of liquid SnI4. This feature allows us to introduce local order parameters that we may use to observe the transition. Unlike the transition in liquid SnI4, the transition from the low-pressure to the high-pressure structure seems sluggish. We speculate that the liquid-liquid critical point of GeI4 is no longer a thermodynamically stable state and is slightly located below the melting curve. As a result, the structural change is said to be a crossover rather than a transition. The behavior of the local-order parameters implies a metastable extension of the liquid-liquid phase boundary with a negative slope. . © 2017 IOP Publishing Ltd.

  15. The changing structure of the US coal industry: An update, July 1993

    International Nuclear Information System (INIS)

    1993-01-01

    Section 205(a)(2) of the Department of Energy Organization Act of 1977 requires the Administrator of the Energy Information Administration (EIA) to carry out a central, comprehensive, and unified energy data and information program that will collect, evaluate, assemble, analyze, and disseminate data and information relevant to energy resources, reserves, production, demand, technology, and related economic and statistical information. The purpose of this report is to provide a comprehensive overview of changes in the structure of the US coal industry between 1976 and 1991. The structural elements examined include the number of mines, average mine size, the size distribution of mines, and the size distribution of coal firms. The report measures changes in the market shares of the largest coal producers at the national level and in various regions. The Central Appalachian low-sulfur coal market is given special attention, and the market for coal reserves is examined. A history of mergers in the coal industry is presented, and changes in the proportions of US coal output that are produced by various types of companies, including foreign-controlled firms, are described. Finally, the impact of post-1991 mergers on the structure of the industry is estimated. The legislation that created the EIA vested the organization with an element of statutory independence. The EIA does not take positions on policy questions. The EIA's responsibility is to provide timely, high-quality information and to perform objective, credible analyses in support of deliberations by both public and private decisionmakers. Accordingly, this report does not purport to represent the policy positions of the US Department of Energy or the Administration

  16. Composition and structure of Pinus koraiensis mixed forest respond to spatial climatic changes.

    Directory of Open Access Journals (Sweden)

    Jingli Zhang

    Full Text Available BACKGROUND: Although some studies have indicated that climate changes can affect Pinus koraiensis mixed forest, the responses of composition and structure of Pinus koraiensis mixed forests to climatic changes are unknown and the key climatic factors controlling the composition and structure of Pinus koraiensis mixed forest are uncertain. METHODOLOGY/PRINCIPAL FINDINGS: Field survey was conducted in the natural Pinus koraiensis mixed forests along a latitudinal gradient and an elevational gradient in Northeast China. In order to build the mathematical models for simulating the relationships of compositional and structural attributes of the Pinus koraiensis mixed forest with climatic and non-climatic factors, stepwise linear regression analyses were performed, incorporating 14 dependent variables and the linear and quadratic components of 9 factors. All the selected new models were computed under the +2°C and +10% precipitation and +4°C and +10% precipitation scenarios. The Max Temperature of Warmest Month, Mean Temperature of Warmest Quarter and Precipitation of Wettest Month were observed to be key climatic factors controlling the stand densities and total basal areas of Pinus koraiensis mixed forest. Increased summer temperatures and precipitations strongly enhanced the stand densities and total basal areas of broadleaf trees but had little effect on Pinus koraiensis under the +2°C and +10% precipitation scenario and +4°C and +10% precipitation scenario. CONCLUSIONS/SIGNIFICANCE: These results show that the Max Temperature of Warmest Month, Mean Temperature of Warmest Quarter and Precipitation of Wettest Month are key climatic factors which shape the composition and structure of Pinus koraiensis mixed forest. Although the Pinus koraiensis would persist, the current forests dominated by Pinus koraiensis in the region would all shift and become broadleaf-dominated forests due to the dramatic increase of broadleaf trees under the future global

  17. The Incorporation of Ribonucleotides Induces Structural and Conformational Changes in DNA.

    Science.gov (United States)

    Meroni, Alice; Mentegari, Elisa; Crespan, Emmanuele; Muzi-Falconi, Marco; Lazzaro, Federico; Podestà, Alessandro

    2017-10-03

    Ribonucleotide incorporation is the most common error occurring during DNA replication. Cells have hence developed mechanisms to remove ribonucleotides from the genome and restore its integrity. Indeed, the persistence of ribonucleotides into DNA leads to severe consequences, such as genome instability and replication stress. Thus, it becomes important to understand the effects of ribonucleotides incorporation, starting from their impact on DNA structure and conformation. Here we present a systematic study of the effects of ribonucleotide incorporation into DNA molecules. We have developed, to our knowledge, a new method to efficiently synthesize long DNA molecules (hundreds of basepairs) containing ribonucleotides, which is based on a modified protocol for the polymerase chain reaction. By means of atomic force microscopy, we could therefore investigate the changes, upon ribonucleotide incorporation, of the structural and conformational properties of numerous DNA populations at the single-molecule level. Specifically, we characterized the scaling of the contour length with the number of basepairs and the scaling of the end-to-end distance with the curvilinear distance, the bending angle distribution, and the persistence length. Our results revealed that ribonucleotides affect DNA structure and conformation on scales that go well beyond the typical dimension of the single ribonucleotide. In particular, the presence of ribonucleotides induces a systematic shortening of the molecules, together with a decrease of the persistence length. Such structural changes are also likely to occur in vivo, where they could directly affect the downstream DNA transactions, as well as interfere with protein binding and recognition. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  18. Mechanistic Processes Controlling Persistent Changes of Forest Canopy Structure After 2005 Amazon Drought

    Science.gov (United States)

    Shi, Mingjie; Liu, Junjie; Zhao, Maosheng; Yu, Yifan; Saatchi, Sassan

    2017-12-01

    The long-term impact of Amazonian drought on canopy structure has been observed in ground and remote sensing measurements. However, it is still unclear whether it is caused by biotic (e.g., plant structure damage) or environmental (e.g., water deficiency) factors. We used the Community Land Model version 4.5 (CLM4.5) and radar backscatter observations from SeaWinds Scatterometer on board QuikSCAT (QSCAT) satellite to investigate the relative role of biotic and environmental factors in controlling the forest canopy disturbance and recovery processes after the 2005 Amazonian drought. We validated the CLM4.5 simulation of the drought impact and the recovery of leaf carbon (C) pool, an indicator of canopy structure, over southwestern Amazonia with QSCAT backscatter observations, which are sensitive to canopy structure change. We found that the leaf C pool simulated by CLM4.5 recovered to the 2000-2009 mean level (343 g C m-2) in 3 years after a sharp decrease in 2005, consistent with the QSCAT observed slow recovery. Through sensitivity experiments, we found that the slow C recovery was primarily due to biotic factors represented by the canopy damage and reduction of plant C pools. The recovery of soil water and the coupling between water and C pools, which is an environmental factor, only contributes 24% to the leaf C recovery. The results showed (1) the strength of scatterometer backscatter measurements in capturing canopy damage over tropical forests and in validating C cycle models and (2) the biotic factors play the dominant role in regulating the drought induced disturbance and persistent canopy changes in CLM4.5.

  19. Composition and structure of Pinus koraiensis mixed forest respond to spatial climatic changes.

    Science.gov (United States)

    Zhang, Jingli; Zhou, Yong; Zhou, Guangsheng; Xiao, Chunwang

    2014-01-01

    Although some studies have indicated that climate changes can affect Pinus koraiensis mixed forest, the responses of composition and structure of Pinus koraiensis mixed forests to climatic changes are unknown and the key climatic factors controlling the composition and structure of Pinus koraiensis mixed forest are uncertain. Field survey was conducted in the natural Pinus koraiensis mixed forests along a latitudinal gradient and an elevational gradient in Northeast China. In order to build the mathematical models for simulating the relationships of compositional and structural attributes of the Pinus koraiensis mixed forest with climatic and non-climatic factors, stepwise linear regression analyses were performed, incorporating 14 dependent variables and the linear and quadratic components of 9 factors. All the selected new models were computed under the +2°C and +10% precipitation and +4°C and +10% precipitation scenarios. The Max Temperature of Warmest Month, Mean Temperature of Warmest Quarter and Precipitation of Wettest Month were observed to be key climatic factors controlling the stand densities and total basal areas of Pinus koraiensis mixed forest. Increased summer temperatures and precipitations strongly enhanced the stand densities and total basal areas of broadleaf trees but had little effect on Pinus koraiensis under the +2°C and +10% precipitation scenario and +4°C and +10% precipitation scenario. These results show that the Max Temperature of Warmest Month, Mean Temperature of Warmest Quarter and Precipitation of Wettest Month are key climatic factors which shape the composition and structure of Pinus koraiensis mixed forest. Although the Pinus koraiensis would persist, the current forests dominated by Pinus koraiensis in the region would all shift and become broadleaf-dominated forests due to the dramatic increase of broadleaf trees under the future global warming and increased precipitation.

  20. Structural and volume changes and their correlation in electron irradiated alkali silicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Gavenda, Tadeáš, E-mail: gavendat@vscht.cz [Department of Glass and Ceramics, University of Chemical Technology, Technicka 5, CZ-166 28 Prague (Czech Republic); Gedeon, Ondrej [Department of Glass and Ceramics, University of Chemical Technology, Technicka 5, CZ-166 28 Prague (Czech Republic); Jurek, Karel [Institute of Physics, Academy of the Czech Republic, Na Slovance 2, CZ-182 21 Prague (Czech Republic)

    2017-04-15

    Highlights: • Volume changes were correlated with both incubation dose and Raman spectra. • Irradiation decreases Si-O-Si angle and increases the amount of three-membered rings. • Levelling of the pits depends on the dose below and above incubation dose. • Restoration of the original structure was limited to low-frequency region. - Abstract: Two binary alkali silicate glasses (15K{sub 2}O·85SiO{sub 2} – denoted as K15 and 15Li{sub 2}O·85SiO{sub 2} – denoted as Li15) were irradiated by 50 keV electron beams with doses within the range of 2.1–15.9 kC/m{sup 2}. Volume changes induced by electron irradiation were monitored by means of Atomic Force Microscopy (AFM). Raman spectra were taken from the irradiated spots to observe structural changes. Volume compaction observed at lower doses was correlated with the increase of the D2 peak. Volume expansion at higher doses was related to migration of alkali ions. Irradiated glasses were annealed at 400 °C and 500 °C for 60 min. After annealing irradiated spots were again examined by AFM and Raman spectroscopy in order to determine volume and structural relaxation of radiation induced changes. Annealing at higher temperatures resulted in the levelling of the pits created by irradiation, but only for doses below incubation dose. The pits created by doses above incubation dose were not levelled. Annealing caused decrease of D2 peak and shift of the Si-O-Si vibrations band in direction to original structure. Low-frequency region of annealed Li15 glass was undistinguishable from that of pristine glass, while annealing of K15 glass did not result in the full reversion to the original shape. The differences between glasses were attributed to higher T{sub g} of K15 glass. Q-motives bands of both glasses were not completely restored after annealing due to the absence of alkali ions.