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This paper examines the historical manuscripts of the Qur'an preserved at the Suleymaniye Library of Manuscripts, one of the richest libraries in this field, in terms of the names of the Qur'anic surahs. The manuscripts examined here are more than eight hundred and were written in different periods in various places in the Muslim world. The main question of the paper is what names were chosen for the surahs by the scribes. This can reveal the scribes' points of view about the surahs. The paper also addresses the questions how many names mentioned in the literature of tafsir were assigned to the surahs in the manuscripts and how much similar or different the handwritten copies of the Qur'an are to or from the printed ones in terms of the names of the surahs. The paper suggests that the Qur'anic manuscripts are very diverse in terms of the names and that these manuscripts even have some rare names not mentioned in the literature of tafsir. [ABSTRACT FROM AUTHOR]

We propose an unbiased estimate of a filtered version of the mean squared error—the blur-SURE (Stein’s unbiased risk estimate)—as a novel criterion for estimating an unknown point spread function (PSF) from the degraded image only. The PSF is obtained by minimizing this new objective functional over a family of Wiener processings. Based on this estimated blur kernel, we then perform nonblind deconvolution using our recently developed algorithm. The SURE-based framework is exemplified with a number of parametric PSF, involving a scaling factor that controls the blur size. A typical example of such parametrization is the Gaussian kernel. The experimental results demonstrate that minimizing the blur-SURE yields highly accurate estimates of the PSF parameters, which also result in a restoration quality that is very similar to the one obtained with the exact PSF, when plugged into our recent multi-Wiener SURE-LET deconvolution algorithm. The highly competitive results obtained outline the great potential of developing more powerful blind deconvolution algorithms based on SURE-like estimates. [ABSTRACT FROM AUTHOR]

Principal component analysis (PCA) is one of the most widely used methods in multivariate signal processing. An important problem is to select the number of principal components (PCs). In this paper we develop an automatic method for selecting the number of PCs based on Stein's unbiased risk estimator (SURE). In simulations the new method outperforms state of the art cross-validation methods. [ABSTRACT FROM AUTHOR]

In this article, we develop a modern perspective on Akaike's information criterion and Mallows's C p for model selection, and propose generalisations to spherically and elliptically symmetric distributions. Despite the differences in their respective motivation, C p and Akaike's information criterion are equivalent in the special case of Gaussian linear regression. In this case, they are also equivalent to a third criterion, an unbiased estimator of the quadratic prediction loss, derived from loss estimation theory. We then show that the form of the unbiased estimator of the quadratic prediction loss under a Gaussian assumption still holds under a more general distributional assumption, the family of spherically symmetric distributions. One of the features of our results is that our criterion does not rely on the specificity of the distribution, but only on its spherical symmetry. The same kind of criterion can be derived for a family of elliptically contoured distribution, which allows correlations, when considering the invariant loss. More specifically, the unbiasedness property is relative to a distribution associated to the original density. [ABSTRACT FROM AUTHOR]

We propose a powerful denoising method to attenuate random noises in seismic images. The method is a combination of recently developed tools of multiscale, multidirectional curvelets and second-order total-variation (SOTV) regularization. Directional derivative characteristic of SOTV helps an improvement in the quality of final image by suppressing fine-scale artifacts due to curvelets. We formulate the problem in a convex constrained optimization setting to be tackled efficiently by split Bregman iterations. Then the discrepancy principle and Steins unbiased risk estimate (SURE) are used as two stopping criteria to determine the optimum number of Bregman iterations. The SURE score is evaluated at each iteration via stochastic Monte Carlo (MC) technique. Numerical experiments with different synthetic and real seismic images show that the algorithm converges in a few iterations. Furthermore, the obtained results confirm an improvement in signal-to-noise-ratio (SNR) and structural similarity (SSIM) when using the combined method compared to the cases using curvelets or SOTV. [ABSTRACT FROM AUTHOR]

Algorithms for solving variational regularization of ill-posed inverse problems usually involve operators that depend on a collection of continuous parameters. When the operators enjoy some (local) regularity, these parameters can be selected using the so-called Stein Unbiased Risk Estimator (SURE). While this selection is usually performed by an exhaustive search, we address in this work the problem of using the SURE to efficiently optimize for a collection of continuous parameters of the model. When considering nonsmooth regularizers, such as the popular ℓ1-norm corresponding to soft-thresholding mapping, the SURE is a discontinuous function of the parameters preventing the use of gradient descent optimization techniques. Instead, we focus on an approximation of the SURE based on finite differences as proposed by Ramani and Unser for the Monte-Carlo SURE approach. Under mild assumptions on the estimation mapping, we show that this approximation is a weakly differentiable function of the parameters and its weak gradient, coined the Stein Unbiased GrAdient estimator of the Risk (SUGAR), provides an asymptotically (with respect to the data dimension) unbiased estimate of the gradient of the risk. Moreover, in the particular case of soft-thresholding, it is proved to also be a consistent estimator. This gradient estimate can then be used as a basis for performing a quasi-Newton optimization. The computation of the SUGAR relies on the closed-form (weak) differentiation of the nonsmooth function. We provide its expression for a large class of iterative methods including proximal splitting methods and apply our strategy to regularizations involving nonsmooth convex structured penalties. Illustrations of various image restoration and matrix completion problems are given. [ABSTRACT FROM AUTHOR]

Any regularization method requires the selection of a penalty parameter and many model selection criteria have been developed based on various discrepancy measures. Most of the attention has been focused on prediction mean squared error. In this paper we develop a model selection criterion based on regression parameter mean squared error via SURE (Stein's unbiased risk estimator). We then apply this to the l1 penalized least squares problem with grouped variables on over-determined systems. Simulation results based on topology identification of a sparse network are presented to illustrate and compare with alternative model selection criteria. [ABSTRACT FROM AUTHOR]

Ethiopia has been resettling poor rural households both voluntarily and involuntarily from degraded and drought prone highlands to sparsely populated areas in the lowlands since the late 1950s. This study investigated resource entitlement and factors that influence perceived level of food and income security among resettlers of different origins and different length of stay in a district where resettlement has been practiced for over twenty years. The results of the study indicated the need to revisit the country's rural development strategy that puts resettlement as one of the primary methods to ensure food security of vulnerable households given the heterogeneity among settlers in terms of origin, roles of women, and the overall need for minimizing the impact of resettlement on the environment. Selection of origin of settlers, ensuring women's access to resources particularly land, diversification of livelihood activities should be promoted to improve food security. Besides, development of rural infrastructure notably roads and markets should be given due emphasis to enhance the role of non-agricultural income generating activities and thereby reduce dependence on dry forests [ABSTRACT FROM AUTHOR]

This work refers the experience of a study of case realized in the rural community Las Peladas, located in the municipality Bartolome Maso Marquez, of the Granma province. In the same the application of a multi-objective mathematical model like computer tool of aid to the planning appears energetics, in agreement with the specific characteristics of the analyzed locality. The field study was based on the results of a participating survey, the observation and compilation of data that it made possible to obtain a characterization of the community and, this way, of delimiting the necessary parameters for the application of the tool. Five alternatives were evaluated: Aeolian energy, biomass, to pave, hydraulics and the connection to the national network. Of them, the model suggests, that the photovoltaic energy solar exerts the greater influence in the improvement of the integral sustainability of the capitals natural, physical, financial, human and social in the community. [ABSTRACT FROM AUTHOR]

An important question in kernel regression is one of estimating the order and bandwidth parameters from available noisy data. We propose to solve the problem within a risk estimation framework. Considering an independent and identically distributed (i.i.d.) Gaussian observations model, we use Stein's unbiased risk estimator (SURE) to estimate a weighted mean-square error (MSE) risk, and optimize it with respect to the order and bandwidth parameters. The two parameters are thus spatially adapted in such a manner that noise smoothing and fine structure preservation are simultaneously achieved. On the application side, we consider the problem of image restoration from uniform/non-uniform data, and show that the SURE approach to spatially adaptive kernel regression results in better quality estimation compared with its spatially non-adaptive counterparts. The denoising results obtained are comparable to those obtained using other state-of-the-art techniques, and in some scenarios, superior. [ABSTRACT FROM AUTHOR]

"Bize ve dünyaya kaynak" sloganıyla yayımlanmaya başlanan Türkiye Diyânet Vakfı İslam Ansiklopedisi, İslâm’ı doğru tanıtan ve ortaya atılmış olan birtakım yanlış oryantalistik iddiaları da tashih eden ciddi bir eser niteliğindedir. Çoğunlukla Türk ilim adamlarının telifleriyle hazırlanan Ansiklopedi, dünya çapında bir ilgiye mazhar olmaktadır. Bu makalede Ansiklopedi’nin ilk yirmi bir cildinde yer alan Kur’ân sûrelerinin tanıtımına dair bazı maddeler çeşitli yönleriyle incelenmiştir. Sûrelerin tanıtımında ortaya çıkan bazı eksiklikler düzeltilmeye çalışılmıştır.

Müslümanlar için Kur’ân, özellikle dînî konularda en temel başvuru kaynağıdır. Savunulan düşüncenin haklılığını ispat etmenin en sağlam yolu Kur’ânî referanslara dayanmaktır. Bu durum bazen bir nasstan birbirine muhalif iki düşüncenin ortaya çıkmasına sebep olabilmektedir. Farklı iki anlayışın ortaya çıktığı konulardan biri de "efdaliyyet"tir. Bu tartışmanın temel konusu Kur’ân’daki sureler ve ayetler arasında üstünlük olup olmadığı hususudur.

In this article, it was given information about topic, content and revelation reason of Rad surah, analysis of inflection, last vowels and key words of its 41st chapter were done. In the light of narrative, perceptive and mystical comments and scientific information that parallelly were arised as 21st century technological developments, concerned chapter was investigated. All in all, besides real, metaphorical and allusive meanings, the chapter was taken into consideration the scientific facts of modern science were reached. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the authors discuss various papers within the issue on topics including urban ecosystem services, conservation of urban biodiversity, and interactions between urban environment and urban culture.

Abstract: In this paper, we aim at recovering an unknown signal from noisy measurements , where Φ is an ill-conditioned or singular linear operator and w accounts for some noise. To regularize such an ill-posed inverse problem, we impose an analysis sparsity prior. More precisely, the recovery is cast as a convex optimization program where the objective is the sum of a quadratic data fidelity term and a regularization term formed of the -norm of the correlations between the sought after signal and atoms in a given (generally overcomplete) dictionary. The -sparsity analysis prior is weighted by a regularization parameter . In this paper, we prove that any minimizer of this problem is a piecewise-affine function of the observations y and the regularization parameter λ. As a byproduct, we exploit these properties to get an objectively guided choice of λ. In particular, we develop an extension of the Generalized Stein Unbiased Risk Estimator (GSURE) and show that it is an unbiased and reliable estimator of an appropriately defined risk. The latter encompasses special cases such as the prediction risk, the projection risk and the estimation risk. We apply these risk estimators to the special case of -sparsity analysis regularization. We also discuss implementation issues and propose fast algorithms to solve the -analysis minimization problem and to compute the associated GSURE. We finally illustrate the applicability of our framework to parameter(s) selection on several imaging problems. [Copyright &y& Elsevier]

This paper investigates the relationship between medical treatment costs and the length of hospital stays resulting from motorcycle crashes involving the elderly. The World Health Organization defines ‘elderly’ as people more than 65 years old. The sample for this study consisted of data for the year 2007 collected by the Bureau of National Health Insurance, Taiwan. We develop models for predicting medical costs and the length of hospital stays based on diagnosis, hospital and user types. The seemingly unrelated regression equation (SURE) model was applied first to investigate the relationship between medical costs and the length of hospital stays. The SURE model shows that the type of injury (e.g. head injury) is statistically significant and has positive effects on medical costs for motorcycle crashes involving the elderly in Taiwan. Due to the statistical insignificance of the dependency between medical costs and length of hospital stays, two separate simple linear regression models were subsequently estimated. For motorcycle crashes, patients over 80 years old had the highest medical costs. The findings reinforce the need for transportation authorities to focus on preventing certain types of injuries that are particularly serious and costly for the elderly in Taiwan. [ABSTRACT FROM AUTHOR]

The Gaussian mixture is a patch prior that has enjoyed tremendous success in image processing. In this work, by using Gaussian factor modeling, its dedicated expectation maximization (EM) inference, and a statistical filter selection and algorithm stopping rule, we develop SURE (Stein's unbiased risk estimator) guided piecewise linear estimation (S-PLE), a patch-based prior learning algorithm capable of delivering state-of-the-art performance at image denoising. In light of this algorithm's features and its results, we also seek to address the number of components to be included when setting up a Gaussian mixture for image patch modeling. By juxtaposing both options, we show that a simple learned prior can perform as well as, if not better than, a much richer yet fixed prior. [ABSTRACT FROM AUTHOR]

This article uses a consumer theory-based systemic approach to model the demand for monetary liquid asset holdings in Chile. We implement the suggestions and caveats of aggregation theory for the estimation of a demand system for liquid assets (monies) in static, dynamic and time-varying parameters setups. Our results are robust and theoretically consistent with consumer theory restrictions, as a system derived from a utility maximizing framework and a quasi concave utility function. In our estimations, we find stability of interest rate elasticities, in contrast to previous related literature. We also document evidence that long (short) maturity rates are associated to less (more) liquid assets. [ABSTRACT FROM PUBLISHER]

Given limited resource availability in a developing nation like India, faced with high incidences of crime, it is important to optimize on the resources spent in combating crime by channelling them to proper direction. This requires an understanding of the actual and overall level of crime across India. Our paper provides a complete understanding of the various indicators of violent crime and the determinants of these crimes in India using district level data for three census years, namely, 1981, 1991 and 2001. We construct three alternative crime-burden indices. Including a variable like voter turnout in state election at the district level, we document significant impact of public awareness to reduce and combat crime. The constructed crime burden index shows that states located in northern parts of India have more incidences of crime compared to states in the south. We also find that our estimated crime-burden indices tend to report in general a higher level of crime-burden than the average based index. This suggests controlling for the factors beyond population while constructing the aggregate crime-burden index for any country is essential. Our work although is limited to the Indian data, we however, believe that this can be easily applied to various other countries. [ABSTRACT FROM AUTHOR]

The purpose of this study is to present the findings of researches, aspects of literature and suggestions of training and reference books about releasing time and duration of a tourniquet if it is a correct application. To present the historical process of tourniquet application, we searched the words "tourniquet", "remove", "release", "time", and "duration" at the published articles and we reviewed some of these items. And also some training sheets and reference books about medical support of military operations, and hemorrhage control are reviewed for the purpose of determining the correct procedure about removing or releasing a tourniquet. All the medical or non-medical military personnel know the time of tourniquet application. There is almost no question on it. But, the question of "when should a tourniquet be released?" occurs, with all its uncertainty, in person's mind. Old aspects recommend that tourniquet should be released in every 15-30 minutes intervals, but new studies show and current training books recommend that tourniquet can be used safely within two hours and a tourniquet should not be released unless the hemorrhage can be controlled surgically. Despite all the fear of tourniquet complications, it should not be avoided to use when required. But soldiers should know issues about tourniquets especially releasing time of it. [ABSTRACT FROM AUTHOR]

Purpose – The aim of this paper is to show how provisions of the Supplemental Revenue Assistance Payments (SURE) program impacts production practices, and empirically examine changes in crop insurance participation rates as a means of measuring producer responses to the program. Design/methodology/approach – The structure of the SURE program is described and a stylized theoretical model is used to show the SURE program's effects on farm-level crop insurance and production decisions. A county-level cross-sectional empirical specification with regional fixed effects is used to test the hypothesis that producers who are most likely to benefit from production practice re-optimization are more likely to participate in crop insurance. Findings – Results from empirical analyses of corn, soybean, and wheat production areas show that the SURE program has had substantial impacts on crop insurance participation by producers who are more likely to receive SURE indemnities and exploit moral hazard opportunities. Research limitations/implications – Because the program has only recently been introduced, empirical estimates of the program's long-run impacts are not estimable. Practical implications – Results indicate that the program can have unexpected market consequences, with increased frequency and size of SURE indemnity claims than the Congressional Budget Office anticipated and increases in aggregate tax payer subsidies for both the crop insurance and SURE program. These outcomes can have important implications on motivating a restructuring of the program in the next farm bill. Social implications – Increased tax payer expenditures on the SURE and crop insurance programs in the form of subsidies can lead to non-trivial reductions in social welfare. Originality/value – This research is the first to develop a rigorous model of the SURE program's impacts on producer responses and associated effects on crop insurance participation. The study also provides empirical evidence of these effects. [ABSTRACT FROM AUTHOR]

Ralstonia solanacearum is a soil-borne xylem-inhibited pathogen and causes a deadly wilting disease on a wide range of crops. This bacterium can also colonize many weeds and native plants without necessarily causing symptoms, leading to devastating epidemiological consequences; however, little is known about the biology. A R. solanacearum mutant harbouring a transposon insertion in the annotated gene RSc1206 was previously shown to retain virulence in tomato but displayed reduced virulence in model weed host Arabidopsis. In this study, we investigated the function of RSc1206 in bacterial pathogenesis in weed hosts. RSc1206 encodes a putative protein that is homologous to E. coli NlpD, and the organization of RSc1206-related gene cluster is mostly conserved among representative gram-negative bacteria analyzed. We therefore designate it R. solanacearum gene nlpD. Microscopic data revealed that the nlpD mutant had defects in cell separation and envelope integrity. An increased sensitivity to hydrophobic toxic chemicals confirmed that the cell integrity of the nlpD mutant was damaged. In addition, the activity of the nlpD mutant in biofilm formation and motility was reduced. However, enzymatic activity and tobacco pathogenesis assays revealed that this mutant functioned normally in the Type II and III secretion systems. Trans-mutation and trans-complementation analyses further verified that disruption of nlpD function was responsible for the observed defects. Our study provides evidence that NlpD contributes to R. solanacearum cell integrity and pathogenesis in weed host Arabidopsis. [ABSTRACT FROM AUTHOR]

The Sufis of 19th and 20th century were also formal scholars graduated from the madrasa, hence they also lectured in madrasa and gave public sermons in the mosques in addition to writing books in different fields. Writing commentaries on the Holy Quran has a special place among their activities. This article will examine works of the Sufi exegetes who lived in the last two centuries of the Ottoman period. [ABSTRACT FROM AUTHOR]

We propose in this paper an extension of the Non-Local Means (NL-Means) denoising algorithm. The idea is to replace the usual square patches used to compare pixel neighborhoods with various shapes that can take advantage of the local geometry of the image. We provide a fast algorithm to compute the NL-Means with arbitrary shapes thanks to the Fast Fourier Transform. We then consider local combinations of the estimators associated with various shapes by using Stein's Unbiased Risk Estimate (SURE). Experimental results show that this algorithm improve the standard NL-Means performance and is close to state-of-the-art methods, both in terms of visual quality and numerical results. Moreover, common visual artifacts usually observed by denoising with NL-Means are reduced or suppressed thanks to our approach. [ABSTRACT FROM AUTHOR]

Abstract: Globalization, greenhouse gas emissions and energy concerns, emerging vehicle technologies, and improved statistical modeling capabilities make the present moment an opportune time to revisit aggregate vehicle miles traveled (VMT), energy consumption, and greenhouse gas (GHG) emissions forecasting for passenger transportation. Using panel data for the 48 continental states during the period 1998–2008, the authors develop simultaneous equation models for predicting VMT on different road functional classes and examine how different technological solutions and changes in fuel prices can affect passenger VMT. Moreover, a random coefficient panel data model is developed to estimate the influence of various factors (such as demographics, socioeconomic variables, fuel tax, and capacity) on the total amount of passenger VMT in the United States. To assess the influence of each significant factor on VMT, elasticities are estimated. Further, the authors investigate the effect of different policies governing fuel tax and population density on future energy consumption and GHG emissions. The presented methodology and estimation results can assist transportation planners and policy-makers in determining future energy and transportation infrastructure investment needs. [Copyright &y& Elsevier]

Let X be a random vector with distribution Pθ where θ is an unknown parameter. When estimating θ by some estimator φ(X) under a loss function L(θ, φ), classical decision theory advocates that such a decision rule should be used if it has suitable properties with respect to the frequentist risk R(θ, φ). However, after having observed X = x, instances arise in practice in which φ is to be accompanied by an assessment of its loss, L(θ, φ(x)), which is unobservable since θ is unknown. A common approach to this assessment is to consider estimation of L(θ, φ(x)) by an estimator δ, called a loss estimator. We present an expository development of loss estimation with substantial emphasis on the setting where the distributional context is normal and its extension to the case where the underlying distribution is spherically symmetric. Our overview covers improved loss estimators for least squares but primarily focuses on shrinkage estimators. Bayes estimation is also considered and comparisons are made with unbiased estimation. [ABSTRACT FROM AUTHOR]

The medical term "chronic" according to medical dictionaries is long-running, and it is used in reference to both symptoms and diseases. The length of time required to pass to obtain the designation of "chronic", in symptoms or diseases, is not clear. In this article, we attempt to analyze the medical term "chronic" to determine the time period required to pass for the classification of different symptoms and diseases as "chronic". [ABSTRACT FROM AUTHOR]

We investigate potential effects of the Supplemental Revenue Assistance Payments (SURE) program introduced in the 2008 Farm Bill. Results suggest little impact on optimal crop insurance purchase decisions, though the SURE program does seem to provide an incentive for mid-level insurance coverage. For producers in the price counter-cyclical payment (PCCP) program, SURE payments are actually higher (lower) when commodity prices are high (low). This is not the case for producers in the Average Crop Revenue Election (ACRE) program. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Turkish Studies is the property of Electronic Turkish Studies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper focuses on women's participation in the Chilean labor market at a regional level. Traditional methods use region-by-region analyses based on assumptions that perturbances are uncorrelated across regions and, most often, that they share identical determinants. Our research shows that both assumptions are inadequate for describing the data. We thus propose a full-information estimator based on a combination of seemingly unrelated regressions (SURE) and Logit techniques. [ABSTRACT FROM AUTHOR]

Social cohesion is the principal goal behind active labour market policies (ALMPs), including those financed at supra-national level, like the European Social Fund. In this paper we use NUTS4 level data on the local labour market dynamics in an attempt to verify direct and indirect effects of ALMPs. We use data for 2000- 2007 for Poland, while this period comprised both stark increases and reductions in the unemployment rates. Over this time also the financing of ALMPs has been increased considerably, transforming both to higher intensity of ALMPs (wider coverage) and higher extensiveness of these activities (increase in per treatment cost). At the same time, these trends have transmitted into local context with highly heterogeneous composition of instruments used and actual coverage rates and costs. We implement seemingly unrelated regressions (SURE) approach to inquire the effects of ALMPs on inflows and outflows rates among Polish local labour markets. [ABSTRACT FROM AUTHOR]

Copyright of Turk Psikiyatri Dergisi is the property of Turk Psikiyatri Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electronic Turkish Studies is the property of Electronic Turkish Studies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

US asset prices are modelled in the short- and long-run with the use of a seemingly unrelated system using monthly data over the time period, 1983–2004. Once the shocks of 1987, 1997 and post-“9·11” have been accounted for, then volatility only affects the consumption and inflation equations. In the long run excess returns and inflation are driven by consumption growth. Money growth impacts excess returns and inflation via consumption. Income is super exogenous implying that policy can be made conditional on this variable and that in the long run investors are primarily concerned with income growth. [Copyright &y& Elsevier]

Abstract: In this paper, we test for convergence in the environmental performance of a sample of OECD countries, with data ranging from 1971 to 2002. First, we use Data Envelopment Analysis (DEA) to compute two environmental performance indicators (EPIs) in the production theory framework. Second, we propose the use of a sequential multivariate approach to test for convergence in environmental performance. These tests allow us to reconcile the time series literature with the cross-sectional dimension, which is basic when testing for convergence in regional blocs. The SURE technique is used, which allows for the existence of correlations across the series without imposing a common speed of mean reversion. The empirical results show that the group of countries as a whole, as well as the majority of countries considered on an individual basis (results for some countries vary between EPIs), are catching-up with Switzerland (the benchmark country). [Copyright &y& Elsevier]

In this paper we propose the use of a sequential multivariate approach to test for convergence. These tests allow us to reconcile the time series literature with the cross-sectional dimension which is basic when testing for convergence in regional blocs. In addition, this methodology helps to avoid the problem due to the limited dataset length. We apply multivariate unit root tests in two stages. First, we test for non-convergence without identifying the countries within the group that effectively converge and, in a second stage, the countries that converge are identified. The SURE technique allows for the existence of correlations across the series without imposing a common speed of mean reversion. The empirical results for Mercosur countries show that there is evidence of catching up of the small countries towards Brazil and, to some extent, Argentina. In contrast, the evidence of catching-up among the larger countries is weaker. [ABSTRACT FROM AUTHOR]

Abstract: The stationary phase survival protein SurE is a metal ion-dependent phosphatase distributed among eubacteria, archaea, and eukaryotes. In Escherichia coli, SurE has activities as nucleotidase and exopolyphosphatase, and is thought to be involved in stress response. However, its physiological role and reaction mechanism are unclear. We report here the crystal structures of the tetramer of SurE from Thermus thermophilus HB8 (TtSurE) both alone and crystallized with Mn2+ and substrate AMP. In the presence of Mn2+ and AMP, differences between the protomers were observed in the active site and in the loop located near the active site; AMP-bound active sites with the loops in a novel open conformation were found in the two protomers, and AMP-free active sites with the loops in a conventional closed conformation were found in the other two protomers. The two loops in the open conformation are entwined with each other, and this entwining is suggested to be required for enzymatic activity by site-directed mutagenesis. TtSurE exists as an equilibrium mixture of dimer and tetramer in solution. The loop-entwined structure indicates that SurE acts as a tetramer. The structural features and the absence of negative cooperativity imply the half-of-the-sites reactivity mechanism resulting from a pre-existing tendency toward structural asymmetry. [Copyright &y& Elsevier]

Copyright of Electronic Turkish Studies is the property of Electronic Turkish Studies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A new modification is developed on conventional Claus process to increase the overall sulfur recovery as well as to decrease the costs. The modification combines both oxygen enrichment and recycling. The process is simulated and studied for various N2/O2 ratios with and without using SURE double combustion technique. The predictions show that using pure oxygen in combustion, condensing water vapor in a condenser following the first sulfur condenser and recycling the effluent gas to combine it with fresh acid gas feed leads to large savings in the production cost and to a clean environment. However, it leads to a high adiabatic flame temperature which exceeds the maximum allowable temperature of the furnace material of construction as well as its refractory. To avoid these effects, it is necessary to use SURE double combustion technique. The oxygen flow rate to the first combustion stage should not exceed 78% O2. [Copyright &y& Elsevier]

Having constructed a data-based estimation rule, perhaps a logistic regression or a classification tree, the statistician would like to know its performance as a predictor of future cases. There are two main theories concerning prediction error: (1) penalty methods such as Cp, Akaike's information criterion, and Slein's unbiased risk estimate that depend on the covariance between data points and their corresponding predictions; and (2) cross-validation and related nonparametric bootstrap techniques. This article concerns the connection between the two theories. A Rao-Blackwell type of relation is derived in which nonparametric methods such as cross-validation are seen to be randomized versiotis of their covariance penalty counterparts. The model-based penalty methods other substantially better accuracy, assuming that the model is believable. [ABSTRACT FROM AUTHOR]