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AbstractObjectiveIn this study, the objective was to evaluate the cardiovascular and metabolic effects in men with male pattern alopecia beginning before 30 years of age.MethodsTotal of 81 people (41 androgenetic alopecia (AGA) and 40 healthy individuals) were included in the study. Twenty-four-hour ambulatory blood pressure (ABP) measurement, high sensitive C-reactive protein (hsCRP), galectin-3 were studied. Hamilton-Norwood scale (HNS) was used to determine the AGA types of the cases.ResultsThe mean age in the AGA and control groups was 30.3 ± 7.5 and 30.8 ± 6.0, respectively. Twenty-four-hour ABP measurements, hsCRP, and galectin-3 were similar in both groups. There was a positive correlation between HNS grade with age, BMI, triglyceride levels and fasting blood glucose levels in individuals with AGA. Similarly, there was a positive correlation between HNS grade with daytime pulse wave velocity and night-time reflection magnitude. A significant positive correlation was determined between hsCRP with BMI and waist circumference, and between galectin-3 with BMI, waist circumference, hip circumference, HOMA-IR in individuals with AGA.ConclusionsThis study shows that AGA patients are similar to the normal population in terms of insulin resistance or metabolic syndrome components. However, hsCRP and galectin-3 appear to be associated with cardiovascular disease risk factors in individuals with AGA.

Self-determination theory is a well-established theory of motivation. This theory provides for fundamental concepts related to human motivation, including self-determination. The mathematization of this theory has been envisaged in a series of two papers by the author. The first paper entitled "Mathematical self-determination theory I: Real representation" addressed the representation of the theory in reals. This second paper is in continuation of it. The representation of the first part allows to abstract the results in more general mathematical structures, namely, affine spaces. The simpler real representation is reobtained as a special instance. We take convexity as the pivotal starting point to generalize the whole exposition and represent self-determination theory in abstract affine spaces. This includes the affine space analogs of the notions of internal locus, external locus, and impersonal locus, of regulated and graded motivation, and self-determination. We also introduce polar coordinates in Euclidean affine motivation spaces to study self-determination on radial and angular line segments. We prove the distributivity of the lattice of general self-determination in the affine space formulation. The representation in an affine space is free in the choice of primitives. However, the different representations, in reals or affine, are shown to be unique up to canonical isomorphism. The aim of this paper is to extend on the results obtained in the first paper, thereby to further lay the mathematical foundations of self-determination motivation theory. • Mathematization of self-determination theory. • Combinatorial definitions and characterizations of self-determination. • Algebraic self-determination. • Self-determination theory in reals. • Self-determination theory in affine space. [ABSTRACT FROM AUTHOR]

In two parts, MSDT1 this paper and MSDT2 the follow-up paper, we treat the topic of mathematical self-determination theory. MSDT1 considers the real representation, MSDT2 the affine space representation. The aim of the two papers is to lay the mathematical foundations of self-determination motivation theory. Self-determination theory was proposed by Deci and Ryan, which is a popular theory of motivation. The fundamental concepts are extrinsic and intrinsic motivation, amotivation, their type of regulation, locus of causality, and especially, self-determination. First, we give a geometric description of its concepts for the regulated case (no amotivation), as the unit 1-simplex. Thereby, we derive a symmetric definition of self-determination. Second, we extend the geometric description to the regulated and unregulated case, based on a more general ternary model, in internal motivation, external motivation, and amotivation. We define gradations of amotivation (and motivation), as 1-simplexes parallel to the unit 1-simplex. The ternary representation implies the types of strong, weak, and general self-determination, as partial orders on the motivation space. Third, we study the order, lattice, and algebraic properties of self-determination. In a version of polar coordinates, strong self-determination turns out to be a complete lattice on angular line segments, weak self-determination is a complete lattice on radial line segments, and general self-determination entails a complete lattice on the entire motivation space. In addition, the modified polar coordinates are employed to obtain necessary and sufficient conditions for strong, weak, and general self-determination. We propose measures for the strength of an ordinal dependency in self-determination, which are partial metrics on the motivation space. [ABSTRACT FROM AUTHOR]

Self-determination theory, as proposed by Deci and Ryan, postulated different types of motivation regulation. As to the introjected and identified regulation of extrinsic motivation, their internalizations were described as “somewhat external” and “somewhat internal” and remained undetermined in the theory. This paper introduces a constrained regression analysis that allows these vaguely expressed motivations to be estimated in an “optimal” manner, in any given empirical context. The approach was even generalized and applied for simplex structure analysis in self-determination theory. The technique was exemplified with an empirical study comparing science teaching in a classical school class versus an expeditionary outdoor program. Based on a sample of 84 German pupils (43 girls, 41 boys, 10 to 12 years old), data were collected using the German version of the Academic Self-Regulation Questionnaire. The science-teaching format was seen to not influence the pupils' internalization of identified regulation. The internalization of introjected regulation differed and shifted more toward the external pole in the outdoor teaching format. The quantification approach supported the simplex structure of self-determination theory, whereas correlations may disconfirm the simplex structure.

The risk of primary ovarian insufficiency (POI) increases in association with autoimmune conditions. Adequate intake of vitamin D (vit D) and trace elements is required for the immune system to function efficiently. The aim of this study was to evaluate vit D, zinc, and copper blood levels in women with POI who had given birth to at least one child and in women with normal menstrual cycles.

Gauguin (Grouping And Using Glyphs Uncovering Individual Nuances) is statistical data visualization software for the interactive graphical exploration of multivariate data using glyph representations. Glyphs are defined as geometric shapes scaled by the values of multivariate data. Each glyph represents one high-dimensional data point or the prototype (average) of a group or cluster of data points. This paper reviews the capabilities, functionality, and interactive properties of this software package. Key features of Gauguin are illustrated with data from the Programme for International Student Assessment.

Abstract: A row (or column) of an matrix complies with Regular Minimality (RM) if it has a unique minimum entry which is also a unique minimum entry in its column (respectively, row). The number of violations of RM in a matrix is defined as the number of rows (equivalently, columns) that do not comply with RM. We derive a formula for the proportion of matrices with a given number of violations of RM among all matrices with no tied entries. The proportion of matrices with no more than a given number of violations can be treated as the -value of a permutation test whose null hypothesis states that all permutations of the entries of a matrix without ties are equiprobable, and the alternative hypothesis states that RM violations occur with lower probability than predicted by the null hypothesis. A matrix with ties is treated as being represented by all matrices without ties that have the same set of strict inequalities among their entries. [Copyright &y& Elsevier]

Schrepp (2005) points out and builds upon the connection between knowledge space theory (KST) and latent class analysis (LCA) to propose a method for constructing knowledge structures from data. Candidate knowledge structures are generated, they are considered as restricted latent class models and fitted to the data, and the BIC is used to choose among them. This article adds additional information about the relationship between KST and LCA. It gives a more comprehensive overview of the literature and the probabilistic models that are at the interface of KST and LCA. KST and LCA are also compared with regard to parameter estimation and model testing methodologies applied in their fields. This article concludes with an overview of KST-related publications addressing the outlined connection and presents further remarks about possible future research arising from a connection of KST to other latent variable modeling approaches.

AbstractRecently, the coefficient khas been proposed for the selection among competing knowledge structure models for multinomial response data in Knowledge Space Theory, a modern psychometric test theory. This paper presents an application of the coefficient kto empirical data obtained from dichotomously scored inductive reasoning test items. A data set of binary scores for 366 male participants who responded to 27 test items measuring two types of inductive reasoning, ‘verbal analogy’ and ‘geometric-figural matrix completion’, is analyzed. An ‘optimal’ knowledge structure model is derived, selecting among 38 candidate competing models based on the criterion k. This is accomplished by a modified version of Item Tree Analysis, a data-analytic procedure for the derivation of knowledge structures on sets of dichotomous items. The data-analytic solution can be satisfactorily compared to theory-driven models obtained from psychological analyses of the inductive reasoning test items. Such a solution may then be utilized for the efficient computerized, adaptive assessment and training of the ability of inductive reasoning of the types of ‘verbal analogy’ and ‘geometric-figural matrix completion’.

Abstract: This paper investigates the dichotomous Mokken nonparametric item response theory (IRT) axioms and properties under incomparabilities among latent trait values and items. Generalized equivalents of the unidimensional nonparametric IRT axioms and properties are formulated for nonlinear (quasi-ordered) person and indicator spaces. It is shown that monotone likelihood ratio (MLR) for the total score variable and nonlinear latent trait implies stochastic ordering (SO) of the total score variable, but may fail to imply SO of the nonlinear latent trait. The reason for this and conditions under which the implication holds are specified, based on a new, simpler proof of the fact that in the unidimensional case MLR implies SO. The approach is applied in knowledge space theory (KST), a combinatorial test theory. This leads to a (tentative) Mokken-type nonparametric axiomatization in the currently parametric theory of knowledge spaces. The nonparametric axiomatization is compared with the assumptions of the parametric basic local independence model which is fundamental in KST. It is concluded that this paper may provide a first step toward a basis for a possible fusion of the two split directions of psychological test theories IRT and KST. [Copyright &y& Elsevier]

Abstract: Medical research has extensively dealt with the estimation of the accuracy (sensitivity and specificity) of a diagnostic test for screening individuals. In this paper we apply the biometric latent class model with random effects by Qu, Tan, and Kutner [(1996). Random effects models in latent class analysis for evaluating accuracy of diagnostic tests. Biometrics, 52, 797–810] to estimate the response error (careless error and lucky guess) probabilities for dichotomous test items in the psychometric theory of knowledge spaces. The approach is illustrated with simulated data. In particular, we extend this approach to give a generalization of the basic local independence model in knowledge space theory. This allows for local dependence among the indicators given the knowledge state of an examinee and/or for the incorporation of covariates. [Copyright &y& Elsevier]

In animal models of endotoxin, the excess production of NO and the reactive nitrogen species (RNS), are potent oxidant and nitrating agents, lead to lipid peroxidation, apoptosis, tissue dysfunction and injury and inactivate enzymes in many cell types. Although liver functions are well known to deteriorate following bacterial infection, the underlying specific mechanism(s) remain a matter of considerable debate. Therefore, the aim of the present study was to determine the in vivoeffect of bacterial lipopolysaccharides (LPS) on Na+,K+-ATPase activity of guinea pig liver, and to investigate the possible contribution of RNS by measuring of iNOS activity and 3-nitrotyrosine (nTyr) levels. Liver Na+,K+-ATPase activity were maximally inhibited 6 h after LPS injection (p < 0.001). nTyr was not detectable in liver of normal control animals, but was detected markedly in LPS exposed animals. LPS treatment significantly increased iNOS activity of liver (p < 0.001). The regression analysis revealed a very close correlation between Na+,K+-ATPase activity and nTyr levels of LPS treated animals (r = −0.863, p < 0.001). Na+, K+-ATPase activity were also negatively correlated with iNOS activity (r = −0.823, p < 0.003) in inflamed tissues. Our results have strongly suggested that bacterial LPS disturbs activity of membrane Na+,K+-ATPase that may be an important component leading to the pathological consequences such as hepatocyte cell loss and dysfunction in which the production of RNS are increased as in the case of LPS challenge.

AbstractThere is an increasing interest in the concept that oxidant/antioxidant imbalance plays a role in the pathogenesis of chronic obstructive pulmonary disease (COPD). However, most of the studies are concentrated on the local antioxidant/oxidant balance. In this study, we investigated the oxidant/antioxidant balance in systemic circulation of patients with COPD. Serum malonyldialdehyde (MDA), vitamin C and erythrocyte reduced glutathione (GSH) were determined in patients during acute exacerbation and during the stable phase of the disease, and compared with age-and sex-matched healthy controls. The levels of serum MDA, vitamin C and erythrocyte GSH were determined according to Yagi, Beutler and Bauer et al., respectively. Serum MDA levels were significantly higher in patients compared to controls, and during acute exacerbation compared to the stable phase. MDA levels in patients with acute exacerbation and in those in stable phase were also higher than in controls. We found significantly decreased levels of erythrocyte GSH and serum vitamin C in patients with acute exacerbation and stable COPD compared to controls. Although smoking caused an increase in oxidative stress in controls, the measured parameters were not affected by smoking in the patient group. In conclusion, there is a systemic oxidant/antioxidant imbalance in COPD, and this imbalance is probably independent of smoking.

AbstractEndotoxin-induced peroxynitrite formation has been demonstrated in plasma. The aim of this study is to evaluate whether this has an effect on erythrocytes. For this purpose erythrocyte 3-nitrotyrosine (3-NT) level, Na+-K+ATPase and glutathione peroxidase activities were measured both in vivoand in vitro. In vivoperoxynitrite formation was induced in rats by intraperitoneal Escherichia coli(E.coli) injection. Erythrocytes were directly incubated with peroxynitrite in the in vitroexperiment. 3-NT levels were measured by reverse-phase HPLC, glutathione peroxidase, and Na+-K+ATPase activities were measured by spectrophotometric techniques. There was a marked increase in the 3-NT levels in both experiments. However, glutathione peroxidase activity was significantly increased in in vivoexperiments, while decreasing in in vitroconditions. Although Na+-K+ATPase activities were significantly reduced by peroxynitrite in vitro, Na+-K+ATPase activities were similar in control and E.coli-injected rat erythrocytes. Although nitrating effect of peroxynitrite does not seem to be preventable by endogenous antioxidants, this effect of peroxynitrite may not endanger erythrocytes if the oxidative damage of peroxynitrite is prevented.

Inductive item tree analysis is an established method of Boolean analysis of questionnaires. By exploratory data analysis, from a binary data matrix, the method extracts logical implications between dichotomous test items. For example, assume that we have the problems i and j of a test that can be solved or failed by subjects. With inductive item tree analysis, an implication i → j between the items i and j can be uncovered, which has the interpretation "If a subject is able to solve item i , then this subject is also able to solve item j ". Hence, in the current form of the method, solely dichotomous items are considered. In this paper, we extend this approach to the general case of polytomous items, when more than two answer categories are possible. Thus, we introduce extensions of inductive item tree analysis that can deal with nominal polytomous (including dichotomous) and ordinal polytomous, each with item-specific, answer scales. To show their usefulness, the extensions proposed in this paper are illustrated with empirical data examples. • Dichotomous generalization of inductive item tree analysis. • Polytomous generalization of inductive item tree analysis. • Illustration of the extensions with empirical data. [ABSTRACT FROM AUTHOR]

AbstractThe aim of this study was to determine the effect of Escherichia coli ( E.coli)-derived lipopolysaccharide on rat plasma low density lipoprotein (LDL), malondialdehyde and 3-nitrotyrosine levels (an indicator of protein nitration). Six hours after intraperitoneal administration of E.coli, plasma LDL was measured electrophoretically and malondialdehyde level was measured by spectrophotometric method. Plasma malondialdehyde was significantly (p<0.001) elevated in E.coli-injected rats (4.97 ± 1.33; n=10) in comparison to control animals (1.83 ± 0.5; n=10). In addition, plasma 3-nitrotyrosine level, determined by reversephase HPLC, was also increased in the infected group (2.84 ± 1.17 to 0.22 ± 0.13; n=10). This increase was statistically significant (p<0.001). An increased level of oxidation of lipids and 3-nitrotyrosine was observed as a result of free radical-mediated damage in plasma. In conclusion, asymptomatic infections may increase the risk of atherosclerosis by inducing free radical formation and a consequent increase in the oxidation of LDL.