Investigation of the local Fe magnetic moments at the grain boundaries of the Ca2FeReO6 double perovskite

The local Fe ferromagnetic (FM) moment at the grain boundaries of a ceramic sample of Ca2FeReO6 double perovskite was investigated by means of x-ray magnetic circular dichroism spectroscopy at the Fe L-2,L-3 edges and compared to the overall bulk magnetization. We found that, at the grain boundaries, the Fe FM moments at H=5 T are much smaller than expected and that the MxH curve is harder than in the bulk magnetization. These results suggest a larger degree of Fe/Re antisite disorder at the grain boundaries of this sample, shedding light into the intriguing nonmetallic resistivity behavior despite the reported presence of free carriers. (c) 2007 American Institute of Physics.

Low PAPR STBCs from Complex Partial-Orthogonal Designs (CPODs)

Space-time codes from complex orthogonal designs (CODs) with no zero entries offer low Peak to Average power ratio (PAPR) and avoid the problem of turning off antennas. But CODs for 2(a) antennas with a + 1 complex variables, with no zero entries are not known in the literature for a >= 4. In this paper, a method of obtaining no zero entry (NZE) codes, called Complex Partial-Orthogonal Designs (CPODs), for 2(a+1) antennas whenever a certain type of NZE code exists for 2(a) antennas is presented. This is achieved with slight increase in the ML decoding complexity for regular QAM constellations and no increase for other complex constellations. Since NZE CODs have been constructed recently for 8 antennas our method leads to NZE CPODs for 16 antennas. Moreover, starting from certain NZE CPODs for n antennas, a construction procedure is given to obtain NZE CPODs for 2n antennas. The class of CPODs do not offer full-diversity for all complex constellations. For the NZE CPODs presented in the paper, conditions on the signal sets which will guarantee full-diversity are identified. Simulations results show that bit error performance of our codes under average power constraint is same as that of the CODs and superior to CODs under peak power constraint.

Direct bone marrow HSC transplantation enhances local engraftment at the expense of systemic engraftment in NSG mice

Direct bone marrow (BM) injection has been proposed as a strategy to bypass homing inefficiencies associated with intravenous (IV) hematopoietic stem cell (HSC) transplantation. Despite physical delivery into the BM cavity, many donor cells are rapidly redistributed by vascular perfusion, perhaps compromising efficacy. Anchoring donor cells to 3-dimensional (3D) multicellular spheroids, formed from mesenchymal stem/stromal cells (MSC) might improve direct BM transplantation. To test this hypothesis, relevant combinations of human umbilical cord blood-derived CD34(+) cells and BM-derived MSC were transplanted into NOD/SCID gamma (NSG) mice using either IV or intrafemoral (IF) routes. IF transplantation resulted in higher human CD45(+) and CD34(+) cell engraftment within injected femurs relative to distal femurs regardless of cell combination, but did not improve overall CD45(+) engraftment at 8 weeks. Analysis within individual mice revealed that despite engraftment reaching near saturation within the injected femur, engraftment at distal hematopoietic sites including peripheral blood, spleen and non-injected femur, could be poor. Our data suggest that the retention of human HSC within the BM following direct BM injection enhances local chimerism at the expense of systemic chimerism in this xenogeneic model.

Consumer’s comparison between local and imported organic products: A hedonic analysis of the Japanese table wine market

Although hundreds of thousands of organic products are traded on a daily basis, it is less known how imported organic products are evaluated by consumers in an importing country. The paper analyzes Japanese wine point of sale (POS) data to examine whether consumers differentiate between local and imported organic products. The results of our hedonic analyses show that the premium for imported organic red (white) wines is about 42.996 % (8.872 %) while that for domestic red (white) organic wines is about 6.440 % (1.214 %), implying that Japanese consumers pay higher premiums for imported organic agricultural products than for those produced in Japan.

Local numerical modelling of magnetoconvection and turbulence - implications for mean-field theories

During the last decades mean-field models, in which large-scale magnetic fields and differential rotation arise due to the interaction of rotation and small-scale turbulence, have been enormously successful in reproducing many of the observed features of the Sun. In the meantime, new observational techniques, most prominently helioseismology, have yielded invaluable information about the interior of the Sun. This new information, however, imposes strict conditions on mean-field models. Moreover, most of the present mean-field models depend on knowledge of the small-scale turbulent effects that give rise to the large-scale phenomena. In many mean-field models these effects are prescribed in ad hoc fashion due to the lack of this knowledge. With large enough computers it would be possible to solve the MHD equations numerically under stellar conditions. However, the problem is too large by several orders of magnitude for the present day and any foreseeable computers. In our view, a combination of mean-field modelling and local 3D calculations is a more fruitful approach. The large-scale structures are well described by global mean-field models, provided that the small-scale turbulent effects are adequately parameterized. The latter can be achieved by performing local calculations which allow a much higher spatial resolution than what can be achieved in direct global calculations. In the present dissertation three aspects of mean-field theories and models of stars are studied. Firstly, the basic assumptions of different mean-field theories are tested with calculations of isotropic turbulence and hydrodynamic, as well as magnetohydrodynamic, convection. Secondly, even if the mean-field theory is unable to give the required transport coefficients from first principles, it is in some cases possible to compute these coefficients from 3D numerical models in a parameter range that can be considered to describe the main physical effects in an adequately realistic manner. In the present study, the Reynolds stresses and turbulent heat transport, responsible for the generation of differential rotation, were determined along the mixing length relations describing convection in stellar structure models. Furthermore, the alpha-effect and magnetic pumping due to turbulent convection in the rapid rotation regime were studied. The third area of the present study is to apply the local results in mean-field models, which task we start to undertake by applying the results concerning the alpha-effect and turbulent pumping in mean-field models describing the solar dynamo.

Unsteady MHD mixed convection flow over an impulsively stretched permeable vertical surface in a quiescent fluid

The unsteady mixed convection flow of an incompressible laminar electrically conducting fluid over an impulsively stretched permeable vertical surface in an unbounded quiescent fluid in the presence of a transverse magnetic field has been investigated. At the same time, the surface temperature is suddenly increased from the surrounding fluid temperature or a constant heat flux is suddenly imposed on the surface. The problem is formulated in such a way that for small time it is governed by Rayleigh type of equation and for large time by Crane type of equation. The non-linear coupled parabolic partial differential equations governing the unsteady mixed convection flow under boundary layer approximations have been solved analytically by using the homotopy analysis method as well as numerically by an implicit finite difference scheme. The local skin friction coefficient and the local Nusselt number are found to decrease rapidly with time in a small time interval and they tend to steady-state values for t* >= 5. They also increase with the buoyancy force and suction, but decrease with injection rate. The local skin friction coefficient increases with the magnetic field, but the local Nusselt number decreases. There is a smooth transition from the unsteady state to the steady state. (C) 2010 Elsevier Ltd. All rights reserved.

A semi-analytical solution for multilayer diffusion in a composite medium consisting of a large number of layers

Diffusion in a composite slab consisting of a large number of layers provides an ideal prototype problem for developing and analysing two-scale modelling approaches for heterogeneous media. Numerous analytical techniques have been proposed for solving the transient diffusion equation in a one-dimensional composite slab consisting of an arbitrary number of layers. Most of these approaches, however, require the solution of a complex transcendental equation arising from a matrix determinant for the eigenvalues that is difficult to solve numerically for a large number of layers. To overcome this issue, in this paper, we present a semi-analytical method based on the Laplace transform and an orthogonal eigenfunction expansion. The proposed approach uses eigenvalues local to each layer that can be obtained either explicitly, or by solving simple transcendental equations. The semi-analytical solution is applicable to both perfect and imperfect contact at the interfaces between adjacent layers and either Dirichlet, Neumann or Robin boundary conditions at the ends of the slab. The solution approach is verified for several test cases and is shown to work well for a large number of layers. The work is concluded with an application to macroscopic modelling where the solution of a fine-scale multilayered medium consisting of two hundred layers is compared against an “up-scaled” variant of the same problem involving only ten layers.

Local structure of water studied by Compton scattering

This thesis presents a novel application of x-ray Compton scattering to structural studies of molecular liquids. Systematic Compton-scattering experiments on water have been carried out with unprecedented accuracy at third-generation synchrotron-radiation laboratories. The experiments focused on temperature effects in water, the water-to-ice phase transition, quantum isotope effects, and ion hydration. The experimental data is interpreted by comparison with both model computations and ab initio molecular-dynamics simulations. Accordingly, Compton scattering is found to provide unique intra- and intermolecular structural information. This thesis thus demonstrates the complementarity of the technique to traditional real-space probes for studies on the local structure of water and, more generally, molecular liquids.

Non local scale effects on ultrasonic wave characteristics nanorods

In this paper, the nonlocal elasticity theory has been incorporated into classical Euler-Bernoulli rod model to capture unique features of the nanorods under the umbrella of continuum mechanics theory. The strong effect of the nonlocal scale has been obtained which leads to substantially different wave behaviors of nanorods from those of macroscopic rods. Nonlocal Euler-Bernoulli bar model is developed for nanorods. Explicit expressions are derived for wavenumbers and wave speeds of nanorods. The analysis shows that the wave characteristics are highly over estimated by the classical rod model, which ignores the effect of small-length scale. The studies also shows that the nonlocal scale parameter introduces certain band gap region in axial wave mode where no wave propagation occurs. This is manifested in the spectrum cures as the region where the wavenumber tends to infinite (or wave speed tends to zero). The results can provide useful guidance for the study and design of the next generation of nanodevices that make use of the wave propagation properties of single-walled carbon nanotubes. (C) 2010 Elsevier B.V. All rights reserved.

Diagnostic Tests Based on Quantile Residuals for Nonlinear Time Series Models

This thesis studies quantile residuals and uses different methodologies to develop test statistics that are applicable in evaluating linear and nonlinear time series models based on continuous distributions. Models based on mixtures of distributions are of special interest because it turns out that for those models traditional residuals, often referred to as Pearson's residuals, are not appropriate. As such models have become more and more popular in practice, especially with financial time series data there is a need for reliable diagnostic tools that can be used to evaluate them. The aim of the thesis is to show how such diagnostic tools can be obtained and used in model evaluation. The quantile residuals considered here are defined in such a way that, when the model is correctly specified and its parameters are consistently estimated, they are approximately independent with standard normal distribution. All the tests derived in the thesis are pure significance type tests and are theoretically sound in that they properly take the uncertainty caused by parameter estimation into account. -- In Chapter 2 a general framework based on the likelihood function and smooth functions of univariate quantile residuals is derived that can be used to obtain misspecification tests for various purposes. Three easy-to-use tests aimed at detecting non-normality, autocorrelation, and conditional heteroscedasticity in quantile residuals are formulated. It also turns out that these tests can be interpreted as Lagrange Multiplier or score tests so that they are asymptotically optimal against local alternatives. Chapter 3 extends the concept of quantile residuals to multivariate models. The framework of Chapter 2 is generalized and tests aimed at detecting non-normality, serial correlation, and conditional heteroscedasticity in multivariate quantile residuals are derived based on it. Score test interpretations are obtained for the serial correlation and conditional heteroscedasticity tests and in a rather restricted special case for the normality test. In Chapter 4 the tests are constructed using the empirical distribution function of quantile residuals. So-called Khmaladze s martingale transformation is applied in order to eliminate the uncertainty caused by parameter estimation. Various test statistics are considered so that critical bounds for histogram type plots as well as Quantile-Quantile and Probability-Probability type plots of quantile residuals are obtained. Chapters 2, 3, and 4 contain simulations and empirical examples which illustrate the finite sample size and power properties of the derived tests and also how the tests and related graphical tools based on residuals are applied in practice.

The Rocky Road of Social Sustainability : The Impact of Integrated Biodiversity Conservation and Development on the Local Realities in Ranomafana National Park, Madagascar

The objective of this study is to examine the social impacts of the integrated conservation and development project (ICDP) aimed at biodiversity conservation and local socio-economic development in the Ranomafana National Park (RNP), Madagascar. Furthermore, the study explores social sustainability and justice of the ICDP in Ranomafana. This ethnographically informed impact study uses of various field methods. The research material used consists of observation, interviews (key-person and focus group), school children's writings, official statistics and project documents. Fieldwork was conducted in three phases in 2001, 2002 and 2004 in twelve villages around the park, as well as in neighbouring areas of Ranomafana. However, four of those twelve villages were chosen for closer study. This study consists of five independent articles and a concluding chapter. Social impacts were studied through reproductive health indicators as well as a life security approach. Equity and distribution of benefits and drawbacks of ICDP were analysed and the actors related to the conservation in Ranomafana were identified. The children and adolescents' environmental views were also examined. The reproductive health indicators studied showed a poor state of reproductive health in the park area. Moreover, the existing social capital in the villages seemed to be fragmented due to economic difficulties that were partly caused by the conservation regulations. The ICDP in Ranomafana did not pay attention to the heterogeneity of the affected communities even though the local beneficiaries of the ICDP varied according to their ethnicity, living place, wealth, social position and gender. In addition, various conservation actors (local people in various groups, local authorities, tourist business owners, conservation NGOs and scientists) contest their interests over the forest, conservation and its related activities. This study corroborates the same type of evidence and conclusions discussed in other similar cases elsewhere: so called social conservation programmes still cannot meet the needs of the people living near the protected areas; on the contrary, they even have a reverse impact on the people's lives. A fundamental misunderstood assumption in the conservation process in Ranomafana was to consider the local people as a problem for biodiversity conservation. Major reasons for the failure of the ICDP in Ranomafana include a lack of local institutions that would have been able to communicate as equals with the conservation NGOs as well as to transfer the tradition of the authoritarian governance in conservation management together with the over-appreciation of scientific biodiversity, and lack of will to understand the local people's rights to use the forest for their livelihoods.

Local Politicizations : A Comparison of Finns and French Practicing Democracy

This study examines how do the processes of politicization differ in the Finnish and the French local contexts, and what kinds of consequences do these processes have on the local civic practices, the definitions and redefinitions of democracy and citizenship, the dynamics of power and resistance, and the ways of solving controversies in the public sphere. By means of comparative anthropology of the state , focusing on how democracy actually is practiced in different contexts, politicizations the processes of opening political arenas and recognizing controversy are analyzed. The focus of the study is on local activists engaged in different struggles on various levels of the local public spheres, and local politicians and civil servants participating in these struggles from their respective positions, in two middle-size European cities, Helsinki and Lyon. The empirical analyses of the book compare different political actors and levels of practicing democracy simultaneously. The study is empirically based on four different bodies of material: Ethnographic notes taken during a fieldwork among the activities of several local activist groups; 47 interviews of local activists and politicians; images representing different levels of public portrayals from activist websites (Helsinki N=274, Lyon N=232) and from city information magazines (Helsinki-info N=208, Lyon Citoyen N= 357); and finally, newspaper articles concerning local conflict issues, and reporting on the encounters between local citizens and representatives of the cities (January-June in 2005; Helsingin Sanomat N=96 and Le Progrès N= 102). The study makes three distinctive contributions to the study of current democratic societies: (1) a conceptual one by bringing politicization at the center of a comparison of political cultures, and by considering in parallel the ethnographic group styles theory by Nina Eliasoph and Paul Lichterman, the theory on counter-democracy by Pierre Rosanvallon and the pragmatist justification theory by Luc Boltanski and Laurent Thévenot; (2) an empirical one through the triangulation of ethnographic, thematic interview, visual, and newspaper data through which the different aspects of democratic practices are examined; and (3) a methodological one by developing new ways of analyzing comparative cases an application of Frame Analysis to visual material and the creation of Public Justification Analysis for analyzing morally loaded claims in newspaper reports thus building bridges between cultural, political, and pragmatic sociology. The results of the study indicate that the cultural tools the Finnish civic actors had at their disposal were prone to hinder more than support politicization, whereas the tools the French actors mainly relied on were frequently apt for making politicization possible. This crystallization is defined and detailed in many ways in the analyses of the book. Its consequences to the understanding and future research on the current developments of democracy are multiple, as politicization, while not assuring good results as such, is central to a functioning and vibrant democracy in which injustices can be fixed and new directions and solutions sought collectively.

Comparison of partial extraction reagents for assessing potential bioavailability of heavy metals in sediments

Assessment of heavy metal bioavailability in sediments is complex because of the number of partial extraction methods available for the assessment and the general lack of certified reference materials. This study evaluates five different extraction methodologies to ascertain the relative strengths and weaknesses of each method. The results are then compared to previously published work to ascertain the most effective partial extraction technique, which was established to be dilute (0.75 – 1 M) nitric acid solutions. These results imply that single reagent; weak acid extractions provide a better assessment of potentially bioavailable metals than the chelating agents used in sequential extraction methods.

Stereochemical Analysis of Higher α,α-Dialkylglycine Containing Peptides. Characterization of Local Helical Conformations at Dipropylglycine Residues and Observation of a Novel Hydrated Multiple β-Turn Structure in Crystals of a Glycine Rich Peptide

The peptide Boc-Gly-Dpg-Gly-Gly-Dpg-Gly-NHMe (1) has been synthesized to examine the conformational preferences of Dpg residues in the context of a poor helix promoting sequence. Single crystals of 1 were obtained in the space group P21/c with a = 13.716(2) Å, b = 12.960(2) Å, c = 22.266(4) Å, and β = 98.05(1)°; R = 6.3% for 3660 data with |Fo| > 4σ. The molecular conformation in crystals revealed that the Gly(1)-Dpg(2) segment adopts φ, ψ values distorted from those expected for an ideal type II‘ β-turn (φGly(1) = +72.0°, ψGly(1) = −166.0°; φDpg(2) = −54.0°, ψDpg(2) = −46.0°) with an inserted water molecule between Boc-CO and Gly(3)NH. The Gly(3)-Gly(4) segment adopts φ, ψ values which lie broadly in the right handed helical region (φGly(3) = −78.0°, ψGly(3) = −9.0°; φGly(4) = −80.0°, ψGly(4) = −18.0°). There is a chiral reversal at Dpg(5) which takes up φ, ψ values in the left handed helical region. The Dpg(5)-Gly(6) segment closely resembles an ideal type I‘ β-turn (φDpg(5) = +56.0°, ψDpg(5) = +32.0°; φGly(6) = +85.0°, ψGly(6) = −3.0°). Molecules of both chiral senses are found in the centrosymmetric crystal. The C-terminus forms a hydrated Schellman motif, with water insertion into the potential 6 → 1 hydrogen bond between Gly(1)CO and Gly(6)NH. NMR studies in CDCl3 suggest substantial retention of the multiple turn conformation observed in crystals. In solution the observed NOEs support local helical conformation at the two Dpg residues.

Kaupungin savut ja käryt : Helsingin ilmansuojelu 1945-1982

The smoke and fumes of the city: Air protection in Helsinki from 1945 to 1982 This dissertation examines air pollution and air protection in post-war Helsinki. The period studied ends in 1982 when the Air Protection Act entered into force, thus institutionalising air protection in Finland as a socially governed environmental matter. The dissertation is based on the research traditions of environmental politics and urban environmental history. The development of air protection is approached from the perspectives of politicisation and institutionalisation. The dissertation also investigates how air pollution grew into a social issue and presents various discursive ways of analysing air pollution and protection. The primary research material consists of municipal documents and newspapers, while supplementary material includes journal articles and interviews. The event history of air protection is described through an analysis of the material, including source criticism. The social ways of dealing with air pollution and the emergence of air protection are analysed in the light of case-specific air quality disputes from both factual and discursive perspectives. This approach enables the contextualisation of the development of air protection as part of the local history of post-war Helsinki. The dissertation presents the major sources of air pollution in Helsinki and describes the deterioration of air quality in a society which emphasised the primacy of economic prosperity. The air issue emerged during the 1950s in neighbourhood disputes and was exacerbated into a larger problem in the late 1960s. Concurrent to the formation of the field of environmental protection in Finland, an air protection organisation was established in the 1970s in Helsinki. As a result, air protection became a regular part of municipal government. Air protection in Helsinki developed from small-scale policies focused on individual cases into a large, institutionalised air protection system managed by experts. The dissertation research material gave rise to the following major research themes: the economic dimension of the air issue, the role of science in the formation of the environmental problem, and the establishment of norms for acceptable air quality and reasonable limits to air pollution in the urban environment. The paper also discusses the inequitable distribution of the negative effects of air pollution between the residents of different districts. The dissertation concludes that air protection in Helsinki became a local success story although it was long marred by inefficiency and partial failure.