bluuebunny/crossref_metadata_2025 huggingface dataset:
Chromosome regions affecting body weight in egg layers
Authors: HONKATUKIA M. , TUISKULA-HAAVISTO M. , VILKKI J.
Published: October 2007

We have previously mapped quantitative trait loci (QTL) affecting egg production and quality traits using a reciprocal cross of two divergent egg-layer lines. The lines differ also in body weight, and we initially identified genome-wide significant Mendelian QTL for adult body weight at 40 weeks of age and feed intake at 3236 weeks of age. In addition, QTL with parent-of-origin effects were detected for feed intake and body weight. In the present study, a total of five body weight traits (weight at 16, 20, 24, 40 and 60 weeks of age) have been analysed in the same mapping population. New QTL affecting body weight at different ages were found on chromosomes 1, 4, 5, 6, and 13. Both Mendelian QTL and loci with parent-of-origin expression were found. Our findings are in good agreement with the results of previous studies on different mapping populations. The results elucidate the most important chromosome regions affecting weight in poultry in general and may add to the understanding of such loci among domestic animals.;
Organizational learning in the theory of organizational change
Authors: Janicijevic Nebojsa
Published: October 2007

The concept of organizational learning has been presented and placed within the referential frame of the organizational change theory. It appears that organizational changes shows to be a wider concept than organizational learning, since every learning includes change, but every change does not necessarily include learning. Organizational learning presents a particular type of organizational change, one which comprises creation and utilization of knowledge, includes changes of both cognitive structures and behaviors of organizational members, and necessarily is normative by its nature. The referential frame of the theory of organizational change is based on the classification of organizational changes and put together all theories into four perspectives: organizational development, organizational transformation, organizational adaptation and process perspective. It can be concluded that the concept of organizational learning is eclectic one, since it includes all types of organizational changes and encompasses all mentioned perspectives of organizational changes. .
Estimation of the value-at-risk parameter: Econometric analysis and the extreme value theory approach
Authors: Mladenovic Zorica , Mladenovic Pavle
Published: October 2007

In this paper different aspects of value-at-risk estimation are considered. Daily returns of CISCO, INTEL and NASDAQ stock indices are analyzed for period: September 1996 - September 2006. Methods that incorporate time varying variability and heavy tails of the empirical distributions of returns are implemented. The main finding of the paper is that standard econometric methods underestimate the value-at-risk parameter if heavy tails of the empirical distribution are not explicitly taken into account. .
Economic development and direct foreign investment in the transition economies
Authors: Mrdakovic-Cvetkovic Ruzica
Published: October 2007

The paper deals with the problems related to economic development in Serbia and Southeast-European countries. Comparative analysis has been used for distinguishing typical changes of gross domestic product, foreign direct investment and gross domestic product per capita in Serbia, the countries of Southeast Europe and the Commonwealth of Independent States. The analysis indicates that the levels of both the gross domestic product (GDP) and production in Serbia and other countries are currently lower than in 1989, the year generally taken as the beginning of the process of transition from centrally planned to market economies. .
Possibilities for application of comparative advertising and its effects
Authors: Starcevic Sladjana
Published: October 2007

In recent years, it has been evident that one form of competitive advertising gained in its importance - comparative advertising. Although its extensive use has probably been inspired by the belief that the perception of relative superiority of a brand compared to competition could be encouraged in that way, research evidence suggested mixed conclusions about its effectiveness. The paper summarizes the results of previous studies in this area, and in particular those which point out the factors that can influence effectiveness of comparative advertising. Additionally,, the paper summarizes the opinions of some authors about the long-term influence of this form of advertising on brand, and gives the recommendations for its more effective use. .
Logical and historical determination of the Arrow and Sen impossibility theorems
Authors: Boricic Branislav
Published: October 2007

General classification of mathematical statements divides them into universal, those of the form xA , and existential ?xA ones. Common formulations of impossibility theorems of K. J. Arrow and A. K. Sen are represented by the statements of the form "there is no x such that A". Bearing in mind logical equivalence of formulae ??xA and x?A, we come to the conclusion that the corpus of impossibility theorems, which appears in the theory of social choice, could make a specific and recognizable subclass of universal statements. In this paper, on the basis of the established logical and methodological criteria, we point to a sequence of extremely significant "impossibility theorems", reaching throughout the history of mathematics to the present days and the famous results of Arrow and Sen in field of mathematical economics. We close with specifying the context which makes it possible to formulate the results of Arrow and Sen accurately, presenting a new direct proof of Sen?s result, with no reliance on the notion of minimal liberalism. .
The use of propensity score-matching methods in evaluation of active labour market programs in Serbia
Authors: Ognjenovic Kosovka
Published: October 2007

The aim of the paper is to evaluate impacts of active labour market measures in Serbia on the probability of the participants? employment. In the estimation process of average treatment effects, propensity score-matching method was applied. Its use has considerably reduced the bias in evaluation of the average treatment effects, induced by systematic differences between samples of those who participated in the active labour market programmes and those who did not. The estimated impacts of active labour market programmes on the probability of employment were found to be both positive and statistically significant. .
Qualitative response models: A survey of methodology and illustrative applications
Authors: Nojkovic Aleksandra
Published: October 2007

This paper introduces econometric modeling with discrete (categorical) dependent variables. Such models, commonly referred to as qualitative response (QR) models, have become a standard tool of microeconometric analysis. Microeconometric research represents empirical analysis of microdata, i.e. economic information about individuals, households and firms. Microeconometrics has been most widely adopted in various fields, such as labour economics, consumer behavior, or economy of transport. The latest research shows that this methodology can also be successfully transferred to macroeconomic context and applied to time series and panel data analysis in a wider scope. .
Doha round of WTO negotiations and the domestic support for agriculture in Serbia
Authors: Popovic Vesna , Katic Branko
Published: October 2007

Beside the fact that the green box essential inspection has, obviously, not been carried out, the long expected modality draft in the agricultural sector for July 2006 is full of opposing ponts of view and conflicting solutions to the problem. Thus, the negotiations have been completely suspended, as the very result of the lack of agreement in the field of agriculture (market approach and internal support). It is expected that Doha round of WTO negotiations should result with a significant improvement in reduction of trade distortion support. Serbia is in the process of joining the WTO and is intensively working on meeting the obligations that are expected to be completed in the process; in this case, in the field of internal support to agriculture. .
Monopsony in the labor market: Profit vs. Wage maximization
Authors: Suvakovic Djordje, , Radosavljevic Goran
Published: October 2007

This paper compares the efficiency of profit- and wage-maximizing (PM and WM) monopsony in the labor market. We show that, both locally and globally, a PM monopsony may well be dominated by its WM twin, where the local and global dominance are defined with respect to a single (inverse) labor supply function and a single family of such functions. This family is always divided in the two disjoint (sub)families of the PM and WM dominance. We also analyze some major factors that explain the size of these (sub)families. .
Pareto’s optimum in models of general economic equilibrium with the asset market
Authors: Popovic Zoran
Published: October 2007

A model of the general economic equilibrium of sequential structures includes the asset market, where assets are instruments of sequential income redistribution. The model should explain relative prices of commodities, on one hand, and establish the asset pricing as an instrument of income redistribution, on the other, enabling the analysis of sequential income transfers. This paper mainly researches Pareto?s optimum of a defined mathematical model of the general economic equilibrium in both complete and incomplete asset markets. The existence of the latter partly disables an economic system to transfer income through time sequences properly, which results in equilibrium allocations not reaching Pareto?s optimum. .
Shadow economy and public debt sustainability in Turkey
Authors: Burçin Yereli , Seçilmiş Erdem , Başaran Alparslan
Published: October 2007

The aim of this study is to examine the relationship between the shadow economy and public debt in Turkey. We elaborate on the questions regarding the negative effects of shadow economy on the sustainability of public debt observing the estimates about the size of shadow economy in Turkey. In the light of some scholars? estimates, we re-evaluate the macroeconomic situation of Turkey. At the core of the study, we discuss how the government borrowing policies would differ if the shadow economy was included into the legal system. In order to examine the effects of shadow economy on sustainability, we use various sustainability indicators. There is a significant difference observed between the calculations which take into account the volume of shadow economy as a share of economic system and those that exclude shadow economy as an exogenous variable. .
Key factors in strategy choice for an enterprise recovery
Authors: Kontic Ljiljana
Published: October 2007

The main purpose of our research is to construct and apply a framework for strategic choice, which is essential for successful recovery. Based on analysis of relevant literature and empirical studies of recovery, we proposed four different recovery strategies such as management changes, financial restructuring, internal or external strategies. We have identified and included the following seven factors in analytical framework: causes of crisis, the phase of crisis, available resources, organizational life cycle, competitive position, industrial level, and stakeholder influences in organizational survival, especially banks and other creditors. Furthermore, we examined the application of this framework to six case studies of enterprises in Serbia. .
Relationship marketing in digital economy
Authors: Djordjevic Bojan
Published: October 2007

Relationship marketing in digital economy represents a new phase of marketing development in the XXI century. Key features lie in the development of closer relationship and cooperation between companies and their Internet consumers and partners. It was the problem of nonestablished e-relationships that was the main reason for failure of those companies that first started their new, digital environment business. Challenge for companies in the future will be introducing the CRM concept, with the main goal of bringing the high satisfaction and loyalty to their consumers in the e-market. .
R3 fluids
Authors: Caimmi R.
Published: October 2007

The current paper is aimed at getting more insight on three main points concerning large-scale astrophysical systems, namely: (i) formulation of tensor virial equations from the standpoint of analytical mechanics; (ii) investigation on the role of systematic and random motions with respect to virial equilibrium configurations; (iii) determination of extent to which systematic and random motions are equivalent in flattening or elongating the shape of a mass distribution. The tensor virial equations are formulated regardless of the nature of the system and its constituents, by generalizing and extending a procedure used for the scalar virial equations in presence of discrete subunits (Landau and Lifchitz 1966). In particular, the self potential-energy tensor is shown to be symmetric with respect to the exchange of the indices, (Epot)pq = (Epot)qp. Then the results are extended to continuous mass distributions. The role of systematic and random motions in collisionless, ideal, self-gravitating fluids is analysed in detail including radial and tangential velocity dispersion on the equatorial plane, and the related mean angular velocity, ?, is conceived as a figure rotation. R3 fluids are defined as ideal, self-gravitating fluids in virial equilibrium, with systematic rotation around a principal axis of inertia, taken to be x3. The related virial equations are written in terms of the moment of inertia tensor, Ipq, the self potential-energy tensor, (Epot)pq, and the generalized anisotropy tensor, ?pq (Caimmi and Marmo 2005, Caimmi 2006a). Additional effort is devoted to the investigation of the properties of axisymmetric and triaxial configurations. A unified theory of systematic and random motions is developed for R3 fluids, taking into consideration imaginary rotation (Caimmi 1996b, 2006a), and a number of theorems previously stated for homeoidally striated Jacobi ellipsoids (Caimmi 2006a) are extended to the more general case of R3 fluids. The effect of random motion excess is shown to be equivalent to an additional real or imaginary rotation, respectively, inducing flattening (along the equatorial plane) or elongation (along the rotation axis). Then it is realized that a R3 fluid always admits an adjoint configuration with isotropic random velocity distribution. In addition, further constraints are established on the amount of random velocity anisotropy along the principal axes, for triaxial configurations. A necessary condition is formulated for the occurrence of bifurcation points from axisymmetric to triaxial configurations in virial equilibrium, which is independent of the anisotropy parameters. A particularization of general relations is made to the special case of homeoidally striated Jacobi ellipsoid, and some previously known results (Caimmi 2006a) are reproduced. .
Phenomenological approach to the modelling of elliptical galaxies: The problem of the mass-to-light ratio
Authors: Samurovic S.
Published: October 2007

In this paper the problem of the phenomenological modelling of elliptical galaxies using various available observational data is presented. Recently, Tortora, Cardona and Piedipalumbo (2007) suggested a double power law expression for the global cumulative mass-to-light ratio of elliptical galaxies. We tested their expression on a sample of ellipticals for which we have the estimates of the mass-to-light ratio beyond ~ 3 effective radii, a region where dark matter is expected to play an important dynamical role. We found that, for all the galaxies in our sample, we have ? + ? > 0, but that this does not necessarily mean a high dark matter content. The galaxies with higher mass (and higher dark matter content) also have higher value of ?+?. It was also shown that there is an indication that the galaxies with higher value of the effective radius also have higher dark matter content. .
On the density and surface brightness profiles in globular star clusters
Authors: Ninkovic S. , Valjarevic A.
Published: October 2007

A model of mass distribution, applicable to globular star clusters and proposed earlier, is reconsidered. It is shown that it can be related to the well-known Plummer-Schuster formula, and the equations yielding its dimensionless parameters are given. The corresponding surface density is calculated numerically. It is indicated that in a general case the surface density should not be proportional to the surface brightness and a more adequate formula relating these two quantities is proposed. .
Gradient of mean mass of a star in the field of globular clusters
Authors: Valjarevic A.
Published: October 2007

Based on the relevant available data, the distributions of masses and apparent magnitudes of stars belonging to globular star clusters are simulated. The simulations are aimed at examining the influence of the mass-segregation phenomenon on the surface-density profile. It is found that a minor correction should be introduced in order to infer the profile of the surface density from that of the surface brightness. .
Third derivatives of the integrable part of an asteroid Hamiltonian
Authors: Pavlovic R.
Published: October 2007

To apply the theorem of Nekhoroshev (1977) to asteroids, one first has to check whether a necessary geometrical condition is fulfilled: either convexity, or quasi-convexity, or only a 3-jet non-degeneracy. This requires computation of the derivatives of the integrable part of the corresponding Hamiltonian up to the third order over actions and a thorough analysis of their properties. In this paper we describe in detail the procedure of derivation and we give explicit expressions for the obtained derivatives. .
Albert Einstein, cosmos and religion
Authors: Dokovic V. , Grujic P.
Published: October 2007

We consider Einstein's attitude regarding religious as such, from both cosmological and epistemological points of view. An attempt to put it into a wider socio-historical perspective was made, with the emphasis on ethnic and religious background. It turns out that the great scientist was neither atheist nor believer in the orthodox sense and the closest labels one might stick to him in this respect would be pantheism/cosmism (ontological aspect) and agnosticism (episte?mological aspect). His ideas on divine could be considered as a continuation of line traced by Philo of Alexandria, who himself followed Greek Stoics and (Neo-) Platonists and especially Baruch Spinoza. It turns out that Einstein's both scientific (rational aspects) and religious (intuitive aspects) thinking were deeply rooted in the Hellenic culture. His striving to unravel the secrets of the universe and the roots of cosmological order resembles much the ancient ideas of the role of knowledge in fathoming the divine as such, as ascribed to Gnostics. .
The Σ − D relation for planetary nebulae: Preliminary analysis
Authors: Urosevic D. , Vukotic B. , Arbutina B. , Ilic D.
Published: October 2007

An analysis of the relation between radio surface brightness and diameter, so-called ? ? D relation, for planetary nebulae (PNe) is presented: i) the theoretical ? ? D relation for the evolution of bremsstrahlung surface brightness is derived; ii) contrary to the results obtained earlier for the Galactic supernova remnant (SNR) samples, our results show that the updated sample of Galactic PNe does not severely suffer from volume selection effect - Malmquist bias (same as for the extragalactic SNR samples) and; iii) we conclude that the empirical S ? D relation for PNe derived in this paper is not useful for valid determination of distances for all observed PNe with unknown distances. .
Identification of phase-independent spectral lines in close binary V455 CYG: I. Telluric lines
Authors: Cséki A. , Vince I. , Latkovic O. , Antokhin I.I.
Published: October 2007

Spectroscopic observations of close binary star V455 Cygni reveal many lines that originate in interstellar and circumstellar medium and the atmo?sphere of the Earth; we found over two hundred such spectral features, and in this paper we present the list of telluric lines we identified through comparison with HITRAN database of molecular lines. The lines that remain unidentified or show peculiar behavior will be discussed in the second part of the paper. .
CCD measurements of double and multiple stars at NAO Rozhen. III
Authors: Cvetkovic Z. , Pavlovic R. , Strigachev A. , Novakovic B. , Popovic G.M.
Published: October 2007

Using the 2-m telescope of the Bulgarian National Astronomical Observatory at Rozhen, observations of 55 multiple stars were carried out during one night, December 16/17. 2006. This is the third series of CCD measurements of double and multiple stars carried out at Rozhen. In the paper we present the results for the position angle and separation for 49 multiple stars (67 pairs) which could be measured. .
Aims and methods of education: A recapitulation
Authors: Pantic Natasa
Published: October 2007

This paper gives an overview of principal distinction between the aims of the so-called "traditional" and "progressive" education and respective pedagogies associated with each. The term "traditional" education is used to denote the kind of education that prepares people for their role in society as it is, while the term "progressive" is used for education that aspires to equip mankind with capacity to shape the change of society. The paper raises some critical questions about the role of pedagogy in achieving the aims of the progressive model, arguing that the employment of "progressive" methods does not necessarily guarantee the achievement of the commonly professed purposes of progressive education. This is illustrated in the paper by the results of a study in English schools showing how despite the claim of progressive methods, teachers tend to retain traditional attitudes and on the other hand, how even traditional teaching methods can serve the progressive purpose. This is not to advocate for the traditional pedagogy, but to suggest that it might be something other than pedagogy that makes a critical difference in educating liberal-minded citizens of the future. In this sense the paper explores the role of other factors that make a difference towards progressive education, such as democratization of human relations in school ethos and respect for children's freedom.
Pedagogic process modeling: Humanistic-integrative approach
Authors: Boritko Nikolaj
Published: October 2007

The paper deals with some current problems of modeling the dynamics of the subject-features development of the individual. The term "process" is considered in the context of the humanistic-integrative approach, in which the principles of self education are regarded as criteria for efficient pedagogic activity. Four basic characteristics of the pedagogic process are pointed out: intentionality reflects logicality and regularity of the development of the process; discreteness (stageability) in dicates qualitative stages through which the pedagogic phenomenon passes; nonlinearity explains the crisis character of pedagogic processes and reveals inner factors of self-development; situationality requires a selection of pedagogic conditions in accordance with the inner factors, which would enable steering the pedagogic process. Offered are two steps for singling out a particular stage and the algorithm for developing an integrative model for it. The suggested conclusions might be of use for further theoretic research, analyses of educational practices and for realistic predicting of pedagogical phenomena. .
The role of knowledge in critical thinking
Authors: Pesic Jelena
Published: October 2007

The paper discusses the role of knowledge in critical thinking, i.e. a controversial issue of whether critical thinking is general or subject-dependant ability. Analyzed are basic assumptions of the authors who maintain the view of the generality of critical thinking, and those who defend the view that critical thinking is subject dependant, as well as their theoretical and practical arguments in favor of their views. The problem of generality of critical thinking is analyzed on three levels: conceptual (whether it is conceptually possible to speak about critical thinking outside a particular subject context); epistemological (whether the epistemological nature of the ability and skill of critical thinking differs in different domains of human knowledge) and practical (practical implications related to developing the most adequate approach to enhance critical thinking). The outcomes of the analysis suggest that critical thinking has both a general and a subject-dependant components, whose contents require further elaboration based on theoretical and empirical research. Educational implications of the analysis indicate that it is necessary to carefully devise the connection between the desired skills and teaching contents in the curricula which aim at enhancing critical thinking. .
Misconceptions persistent despite school studying
Authors: Antic Slobodanka
Published: October 2007

The paper deals with theoretical research of the phenomenon of misconceptions, i.e. retention (after regular learning during schooling) of unscientific, personal, intuitive understanding of contents from different scientific disciplines. The phenomenon is equally present among pupils, students and adults. The aim of the discussion is to draw attention of scientific and professional audience to the phenomenon which we find is over-present in pedagogic practice but which, so far, has not been sufficiently recognized or discussed in our circles. Additionally, the intention is to consider pedagogic implications of this problem. The paper contains four parts. The first part discusses terminology (similarities and differences). In the second part a typology of misconceptions is offered. Two theoretical approaches/frameworks attempted to explain the phenomenon of misconceptions (traditional and constructivist approach to students? learning) are presented in the third part, while the fourth part focuses on pedagogic implications and importance of this problem for practice, and the strategies for its overcoming (the need for misconceptions to be made visible in the teaching process and for developing situations which will create cognitive conflicts in students, and the like). .
Knowledge, ignorance and faulty knowledge in school
Authors: Avramovic Zoran
Published: October 2007

The paper discusses the issue of school knowledge from the point of view of scientific knowledge, ignorance and faulty knowledge. The starting point is that neither school nor curricula pay attention to what knowledge is, what types of knowledge there are, and what kind of relationship exists between knowledge, ignorance and faulty knowledge. The first part offers an answer to the question what knowledge is. In the second part presented are some theoretical viewpoints on knowledge: gnoseological, sociological and psychological. The third part deals with the notions of ignorance and "faulty" knowledge. Pointed out are some forms of mystical ignorance. The forms of faulty knowledge are: erroneous notions, prejudices, illusions. In the final part, the author considers their relationship in school education. The starting point is that ignorance is a predecessor of any knowledge. The difference between knowledge, ignorance and faulty knowledge exists in every system of school education, but differs in extent and mode when it comes to nature, society, man and art. The author maintains that school should not be defined as an absolute carrier of knowledge, or the system of foolproof knowledge that the student should acquire uncritically. Instead of absolute confidence in scientific knowledge, the paper concludes with suggesting the option of an "elastic form" of school knowledge. This is a type of knowledge which, in its programme, counts on both ignorance and faulty knowledge and their differing roles in studying and real life of students.
How to help a failing student
Authors: Malinic Dusica
Published: October 2007

Different aspects of family and school life, as well as individual characteristics of the student are related to academic failure in various degrees. Once it has become evident that a student is failing in study and learning, and the causes of the failure have been identified, the question arises of how to help him/her to overcome the existing difficulties. Although there are some authors who hold that the intervention in the domain of failure is inconsistent an unconvincing for a number of reasons, in this paper we shall suggest some solutions and recommendations which have been empirically tested. The first part of the paper discusses the advantages and drawbacks of grouping students according to their abilities as one of the strategies of helping unsuccessful students. In the second part we offer some recommendations for work with unsuccessful students based on their preferred learning styles. The third part focuses on examining the effects of counseling on solving the problem of academic failure. Finally, some general suggestions are offered to students, teachers and parents which might prove useful in enhancing academic attainment of failing students.
Educational-material context of the family and students’ attitudes towards schooling
Authors: Bogunovic Blanka , Polovina Nada
Published: October 2007

The impact of the family environment, the mode and the quality of parental stimulation may have a decisive role in the student?s capacity development and realization of given capabilities, and affects particularly the level and the quality of his/her academic attainment. A student?s academic attainment is conditioned by educational aspirations formed in a dynamic interaction with stimulating aspects of the family context. The aims of our study were: to examine the students? attitudes towards schooling, and to obtain answers to the question: which stimulating aspects of family context are the most predictable for the development of educational aspirations, i.e. attitudes towards school and gaining knowledge, educational interests and plans for further education. The sample comprised 1.464 eighth-grade students, aged 15, from 34 primary schools in Serbia. The data were collected by the use of questionnaires filled in by the students and school principals. The results indicate a trend of interrelatedness of cognitively and educationally favorable conditions within the family and positive attitudes towards school, attainment, high aspirations and cognitive and intellectual interests for out-of-school activities. It can be concluded that family stimulation is the resultant of the influence of cultural and educational profile of the family and active parental attitudes regarding education and attainment of their children. The findings could have practical implications in the domain of parents/school cooperation, not only in order to increase the awareness of the importance of active participation of both parties, but also to provide useful guidelines for developing optimal contents and procedures. .
A study on family-school cooperation based on an analysis of school documentation
Authors: Polovina Nada , Stanisic Jelena
Published: October 2007

Family-school cooperation is a very complex process that can be studied at different levels in a number of different ways. This study has covered only some aspects of cooperation between parents and teachers, based on school documentation of a Belgrade elementary school. The study covered analyses of 60 Attendance Registers pertaining to 60 classes with 1289 students from Grade 1 through Grade 8 during an academic year. The unit of analysis included: parents attendance at PTA meetings and individual meetings between parents and teachers. In addition to the frequency of parents? visits to school, the relationship between such registered parents' visits and overall academic performance, grades in conduct, excused and unexcused absence from classes were also considered. The research findings indicated interference between development factors (attitude change in parent-child relationship and growing-up) and parents? informal "theory of critical grades" i.e. transitional processes in schooling. The findings confirmed that parents? individual visits to school were mainly meant to offer an excuse for the student?s absence from school, while attendance at PTA meetings was linked to poor grades in conduct and missed classes (both excused and unexcused). The findings also showed that parents pursued visiting strategies which were pragmatic, less time-consuming and less emotionally draining ones. The closing part refers to discussions on practical use of the study and possible further research. .
Books as a means for stimulating language development of junior primary-school students
Authors: Kovacevic-Gavrilovic Vera , Stevovic Nikoleta
Published: October 2007

The importance of the use of diversified literature for enhancing speech culture in school is recognized and highlighted in Serbian language teaching. In order to find out what selections of literature junior students make and whether free choice of literature results in acquisition of verbal contents and development of verbal expressiveness, we examined the retelling of a previously read text, since this form of verbal behavior is predominantly used for developing students? verbal expressiveness in primary school. The study was conducted on a sample comprising the first, second, third, and fourth grade students of an urban primary school (30 respondents in each group, total = 120). The aim was to register, during the students? retelling, the number and the production of newly acquired words and the correctness of the sentences used. The linguistic material used in the research contained fairy tales, fables, short stories and books that children had spontaneously selected. The analysis showed that books are a useful tool for enhancing both vocabulary expansion and elaboration of sentence structures. When analyzing the results of this type the distinction must be made between the attainment of students who only reproduce expressions and structures and those who productively use new words and structures. .
Aberrant behavior of preschool children: Evaluation of questionnaire
Authors: Fajgelj Stanislav , Bala Gustav
Published: October 2007

In the study metric characteristics of children aberrant behavior questionnaire were analyzed. The analysis was performed on the sample of 1.165 children, aged 4-7, in preschool institutions in several towns of Vojvodina. The questionnaire contained 36 items of the Likert-type scale and was filled in by one parent of each child. The authors examined main metric characteristics of the complete questionnaire, as well as individual items under the Rasche?s measurement model. Generally, parents seldom notice aberrant behavior in their children. Most frequently they notice stubbornness, while very rarely torturing of animals. The item discrimination, on the whole, was found satisfying. The reliability of the questionnaire is 0.84., and all indicators of misfit are within satisfactory ranges. According to differential functioning of the items, the authors found gender and age specificities of parents? evaluation of aberrant behavior of their children. Parents often notice stubbornness and moldiness in girls, and aggression in boys. According to the parent?s observations, younger children are characterized by nail nibbling, ticklishness, and fearfulness, whereas older children show a tendency to force their way by crying, waywardness and bed-wetting. By means of factor analysis of the items, three principal facets of aberrant behavior were determined: overindulgence, shyness and quarrelsomeness. Cross validation (hold out) showed that these three facets were robust in relation to the selection of the sample.
Foundation of theological college in Belgrade and establishment of legal framework for its functioning
Authors: Novakovic Dragan
Published: October 2007

The foundation of the Theological College in Belgrade is viewed in the context of complex political circumstances which followed the restoration of the Serbian state and the efforts of the Serbian church to gain autonomy and the right to elect bishops independently from the Universal Patriarchate. Once having achieved these goals, and with a conviction that the achieved must be defended and maintained by knowledge and education, the state authorities founded a seminary for education of priests and teachers capable to carry out national and spiritual reformation. The accord between the state and the Church regarding the strategic aims enabled the very first vocational school in Serbia to develop continuously its curricula and hire better and better teaching staff each year. However, due to the change of circumstances, the state passed the laws by which it enforced its dominance and showed a clear intent to subordinate theological education to its control. Yet, by its continuous activity during two crucial centuries, the Seminary became a part of collective consciousness, and its cadres contributed actively to the creation of original cultural and value patterns and preservation of national identity of the Serbian nation. The brilliant history of this school and its precious experience can be of great encouragement not only to the researchers of our pedagogical inheritance but also to all those who are engaged in reforming and adjusting education in Serbia to the European standards. .
Further Evidence of a Primary, Causal Association of the PTPN22 620W Variant With Type 1 Diabetes
Authors: Zoledziewska Magdalena , Perra Chiara , Orrù Valeria , Moi Loredana , Frongia Paola , Congia Mauro , Bottini Nunzio , Cucca Francesco
Published: October 2007

OBJECTIVE— The minor allele of the nonsynonymous single nucleotide polymorphism (SNP) +1858C>T within the PTPN22 gene is positively associated with type 1 diabetes and other autoimmune diseases. Genetic and functional data underline its causal effect, but some studies suggest that this polymorphism does not entirely explain disease association of the PTPN22 region. The aim of this study was to evaluate type 1 diabetes association within this gene in the Sardinian population.

RESEARCH DESIGN AND METHODS— We resequenced the exons and potentially relevant portions of PTPN22 and detected 24 polymorphisms (23 SNPs and 1 deletion insertion polymorphism [DIP]), 8 of which were novel. A representative set of 14 SNPs and the DIP were sequentially genotyped and assessed for disease association in 794 families, 490 sporadic patients, and 721 matched control subjects.

RESULTS— The +1858C>T variant, albeit rare in the general Sardinian population (allele frequency 0.014), was positively associated with type 1 diabetes (Pone tail = 3.7 × 10−3). In contrast, the background haplotype in which this mutation occurred was common (haplotype frequency 0.117) and neutrally associated with disease. We did not confirm disease associations reported in other populations for non +1858C>T variants (rs2488457, rs1310182, and rs3811021), although they were present in appreciable frequencies in Sardinia. Additional weak disease associations with rare variants were detected in the Sardinian families but not confirmed in independent case-control sample sets and are most likely spurious.

CONCLUSIONS— We provide further evidence that the +1858C>T polymorphism is primarily associated with type 1 diabetes and exclude major contributions from other purportedly relevant variants within this gene.
Evidence That Processes Other Than Gluconeogenesis May Influence the Ratio of Deuterium on the Fifth and Third Carbons of Glucose
Authors: Bock Gerlies , Schumann William C. , Basu Rita , Burgess Shawn C. , Yan Zheng , Chandramouli Visvanathan , Rizza Robert A. , Landau Bernard R.
Published: October 2007

OBJECTIVE—The deuterated water method uses the ratio of deuterium on carbons 5 and 2 (C5/C2) or 3 and 2 (C3/C2) to estimate the fraction of glucose derived from gluconeogenesis. The current studies determined whether C3 and C5 glucose enrichment is influenced by processes other than gluconeogenesis.

RESEARCH DESIGN AND METHODS—Six nondiabetic subjects were infused with [3,5-2H2]glucose and insulin while glucose was clamped at ∼5 mmol/l; the C5-to-C3 ratio was measured in the in UDP-glucose pool using nuclear magnetic resonance and the acetaminophen glucuronide method.

RESULTS—Whereas the C5-to-C3 ratio of the infusate was 1.07, the ratio in UDP-glucose was <1.0 in all subjects both before (0.75 ± 0.07) and during (0.67 ± 0.05) the insulin infusion.

CONCLUSIONS—These data indicate that the deuterium on C5 of glucose is lost more rapidly relative to the deuterium on C3. The decrease in the C5-to-C3 ratio could result from exchange of the lower three carbons of fructose-6-phosphate with unlabeled three-carbon precursors via the transaldolase reaction and/or selective retention of the C3 deuterium at the level of triosephosphate isomerase due to a kinetic isotope effect. After ingestion of 2H2O, these processes would increase the enrichment of C5 and decrease the enrichment of C3, respectively, with the former causing an overestimation of gluconeogenesis using the C2-to-C5 ratio and the latter an underestimation using the C3-to-C2 ratio. Future studies will be required to determine whether the impact of these processes on the measurement of gluconeogenesis differs among the disease states being evaluated (e.g., diabetes or obesity).
Inactivation of Glyceraldehyde-3-Phosphate Dehydrogenase by Fumarate in Diabetes
Authors: Blatnik Matthew , Frizzell Norma , Thorpe Suzanne R. , Baynes John W.
Published: October 2007

OBJECTIVE—S-(2-succinyl)cysteine (2SC) is formed by a Michael addition reaction of the Krebs cycle intermediate, fumarate, with cysteine residues in protein. We investigated the role of fumarate in chemical modification and inhibition of the sulfhydryl enzyme, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), in vitro and in tissues of diabetic rats.

RESEARCH DESIGN AND METHODS—GAPDH was incubated with fumarate in PBS to assess effects of fumarate on enzyme activity in vitro. Sites of 2SC formation were determined by analysis of tryptic peptides by high-performance liquid chromatography–quadrupole/time-of-flight mass spectrometry. 2SC and fumarate in gastrocnemius muscle of control and streptozotocin-induced diabetic rats were measured by liquid chromatography/tandem mass spectrometry and by gas chromatography/mass spectrometry, respectively. GAPDH was isolated from muscle by immunoprecipitation, and sites of modification of GAPDH were determined by mass spectrometry analysis.

RESULTS—2SC was found, both in vitro and in vivo, about equally at active-site Cys-149 and nucleophilic Cys-244. Inactivation of GAPDH by fumarate in vitro correlated with formation of 2SC. In diabetic compared with control rats, fumarate and 2SC concentration increased approximately fivefold, accompanied by an ∼25% decrease in GAPDH specific activity. The fractional modification of GAPDH by 2SC was significantly increased in diabetic versus control animals, consistent with the decreased specific activity of GAPDH in muscle of diabetic animals.

CONCLUSIONS—Fumarate contributes to inactivation of GAPDH in diabetes. 2SC may be a useful biomarker of mitochondrial stress in diabetes. Modification of GAPDH and other enzymes and proteins by fumarate may contribute to the metabolic changes underlying the development of diabetes complications.
Preventing type 2 diabetes and cardiovascular disease in metabolic syndrome: the role of PPARα
Authors: Plutzky Jorge
Published: October 2007

The clustering of cardiovascular risk factors associated with the metabolic syndrome and type 2 diabetes suggests central mechanisms may exist that account for the presence of these abnormalities. Likewise, this clustering also suggests that key therapeutic targets may exist that could allow improvements in many of these parameters. Extensive data implicate peroxisome proliferator-activated receptor-alpha (PPARα) as an important transcriptional regulator of lipid metabolism, energy balance and inflammation. PPARα is also an established drug target. Experimental data show that activation of PPARα by agonists such as fenofibrate improves dyslipidaemia, increases cholesterol efflux and limits inflammation. All of these effects would also be predicted to decrease atherosclerotic risk. Evidence from surrogate markers in humans is also supportive of the concept that PPARα may act as a central target capable of influencing a variety of different pathways involved in lipid metabolism. Thus, fenofibrate offers the potential for inducing a co-ordinated PPARα response that may improve dyslipidaemia, repress inflammation and limit atherosclerosis in patients with the metabolic syndrome or type 2 diabetes.
Hybrid adaptive predictive control for a dynamic pickup and delivery problem including traffic congestion
Authors: Cortés Cristián E. , Núñez Alfredo , Sáez Doris
Published: October 2007

This paper presents a hybrid adaptive predictive control approach to incorporate future information regarding unknown demand and expected traffic conditions, in the context of a dynamic pickup and delivery problem with fixed fleet size. As the routing problem is dynamic, several stochastic effects have to be considered within the analytical expression of the dispatcher assignment decision objective function. This paper is focused on two issues: one is the extra cost associated with potential rerouting arising from unknown requests in the future, and the other is the potential uncertainty in travel time coming from non‐recurrent traffic congestion from unexpected incidents.

These effects are incorporated explicitly in the objective function of the hybrid predictive controller. In fact, the proposed predictive control strategy is based on a multivariable model that includes both discrete/integer and continuous variables. The vehicle load and the sequence of stops correspond to the discrete/integer variable, adding the vehicle position as an indicator of the traffic congestion conditions. The strategy is analyzed under two scenarios. The first one considers a predictable congestion obtained using historical data (off‐line method) requiring a predictive model of velocities distributed over zones. The second scenario that accepts unpredictable congestion events generates a more complex problem that is managed by using both fault detection and isolation and fuzzy fault‐tolerant control approaches. Results validating these approaches are presented through a simulated numerical example. Copyright © 2007 John Wiley & Sons, Ltd.
Fatal lung fibrosis associated with immunodeficiency and gonadal dysgenesis in 46XX sisters—A new syndrome
Authors: Somech Raz , Somers Gino R. , Chitayat David , Grunebaum Eyal , Atkinson Adelle , Kolomietz Elena , Roifman Chaim M
Published: October 2007

Inherited immune deficiencies are a heterogeneous group of diseases that can be either isolated, with the immune defect being the exclusive manifestation, or associated with other abnormalities. We report on two sisters, born to consanguineous parents of Sri‐Lankan descent, who presented in infancy with immunodeficiency, gonadal dysgenesis, and fatal lung fibrosis. Immune studies demonstrated combined humoral and cellular abnormalities including reduced immunoglobulin production, an absence of lymphoid tissue, markedly reduced T‐lymphocyte numbers and function and reduced newly thymus‐derived T‐cells. Both infants succumbed to rapidly progressive lung fibrosis. Autopsy showed dysgenetic gonads bearing no discernible oocytes. In both, karyotypes were normal female (46,XX). Comparative genome hybridization and analysis of genes known to be associated with severe immune defects in infancy or gonadal dysgenesis showed no abnormality. The distinct findings in these two sisters have not been reported before and thus suggest a hitherto unknown autosomal recessive condition that includes immune dysfunction, gonadal dysgenesis, and pulmonary fibrosis. © 2007 Wiley‐Liss, Inc.