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The iodine content in total diet study (TDS) food samples collected in 2013 was determined by alkaline extraction followed by ICP-MS analysis, as well as by perchloric acid digestion followed by spectrophotometric detection. The ICP-MS method provides lower limits of quantification and higher accuracy. The new method allowed for quantitative determination of iodine content in over 90% of the samples compared to 40% by the former technique. The iodine contents from 266 foods measured in this study were summarized in 11 groups. Bread, dairy, and eggs showed the highest levels of iodine, followed by seafood and meat products. Fruits, vegetables, and beverages contained the lowest amount of iodine.

We introduce and study the family of sets in a finite-dimensional Euclidean space which can be written as the Minkowski sum of an open, bounded, and convex set and a closed convex cone. We establish several properties of the class of such sets, called OM-decomposable, some of which extend related properties holding for the class of Motzkin decomposable sets (i.e., those for which the convex and bounded set in the decomposition is requested to be closed, hence compact).

This paper is intended to provide conditions for the stability of the strong uniqueness of the optimal solution of a given linear semi-infinite optimization (LSIO) problem, in the sense of maintaining the strong uniqueness property under sufficiently small perturbations of all the data. We consider LSIO problems such that the family of gradients of all the constraints is unbounded, extending earlier results of Nürnberger for continuous LSIO problems, and of Helbig and Todorov for LSIO problems with bounded set of gradients. To do this we characterize the absolutely (affinely) stable problems, i.e., those LSIO problems whose feasible set (its affine hull, respectively) remains constant under sufficiently small perturbations. This work has been supported by MICINN of Spain, Grant MTM2008-06695-C03-01/03, by Generalitat Valenciana, by CONACyT of MX, Grant 55681, and by SECTyP-UNCuyo Res. 882/07-R.

The problem of finding a feasible solution to a linear inequality system arises in numerous contexts. We consider solving linear semi-infinite inequality systems via an extension of the relaxation method for finite linear inequality systems. The difficulties are discussed and a convergence result is derived under fairly general assumptions on a large class of linear semi-infinite inequality systems.

The concept of implicit active constraints at a given point provides useful local information about the solution set of linear semi-infinite systems and about the optimal set in linear semi-infinite programming provided the set of gradient vectors of the constraints is bounded, commonly under the additional assumption that there exists some strong Slater point. This paper shows that the mentioned global boundedness condition can be replaced by a weaker local condition (LUB) based on locally active constraints (active in a ball of small radius whose center is some nominal point), providing geometric information about the solution set and Karush-Kuhn-Tucker type conditions for the optimal solution to be strongly unique. The maintaining of the latter property under sufficiently small perturbations of all the data is also analyzed, giving a characterization of its stability with respect to these perturbations in terms of the strong Slater condition, the so-called Extended-Nürnberger condition, and the LUB condition. MICINN of Spain, Grant MTM2008-06695-C03-01, CONACyT of MX.Grant 55681 and SECYT-UNCuyo of Argentina, Grant Res. 1094/09-R.

Seventy-six promising bread winter wheat lines were investigated in relation to the allelic composition of grain storage proteins. The aim of the study was: i) to find out a possible relation between wheat quality and the separate low molecular loci and ii) to examine the potential of some of the existing Glu-A3 alleles to increase the quality. Five indices were investigated that covered almost all aspects of grain quality: sedimentation value, wet gluten content, dough stability, bread volume, quality index and valorimeter. The samples for quality analysis were from a 3-year period of investigation. Different statistical approaches were used to study the influence of Glu-A3 on the level of the indices. The LMW-GS were determined by SDS-PAGE (Payne et al. 1980). It was determined that locus Glu-A3 had the strongest influence on quality among the loci, that determine the low molecular glutenins. The Glu-A3 alleles influenced the end-use quality irrespective of the HMW-GS and LMW-GS composition background against which their effect was expressed. There were important variations among the separate alleles of Glu-A3 locus for their direct effect on end-used quality. Glu-A3f had strong positive effect on the end-use quality against the background of all HMW combinations. Glu-A3b had a similar positive effect. The Glu-A3b allele was connected with high quality in wheat but its effect was weaker than that of Glu-A3f and was not significant for some of the investigated indices.

Seventy-three common winter wheat varieties developed throughout the breeding history of the DAI were investigated for their diversity of allelic variants on storage proteins component composition in grain. The high- and low molecular weight protein structures were determined by the widely used SDS-PAGE method of Payne et al. (1980). The ratio between the individual alleles on the loci of high and low molecular weight glutenin was analyzed. The change in the HMW-score was followed according to the period when the respective varieties were developed. The configuration Glu-A1 b , GluB1 c , Glu-D1 d , which was established in about 45% of the investigated genotypes, was most frequent in the high-molecular variants of glutenin. Concerning the low-molecular weight glutenins in 21 out of the 73 investigated varieties, the combination Glu-A3 c , Glu-B3 b , Glu-D3 c was observed; it coincided with the spectrum of the widely used variety Bezostaya 1. Highest diversity was established in the allelic variants of Glu...

We consider unconstrained finite dimensional multi-criteria optimization problems, where the objective functions are continuously differentiable. Motivated by previous work of Brosowski and da Silva (1994), we suggest a number of tests (TEST 1–4) to detect, whether a certain point is a locally (weakly) efficient solution for the underlying vector optimization problem or not. Our aim is to show: the points, at which none of the TESTs 1–4 can be applied, form a nowhere dense set in the state space. TESTs 1 and 2 are exactly those proposed by Brosowski and da Silva. TEST 3 deals with a local constant behavior of at least one of the objective functions. TEST 4 includes some conditions on the gradients of objective functions satisfied locally around the point of interest. It is formulated as a Conjecture. It is proven under additional assumptions on the objective functions, such as linear independence of the gradients, convexity or directional monotonicity.

A linear inequality system with infinitely many constraints is polynomial (analyti- cal) if its index set is a compact interval of the real line and all its coe_cients are polynomial (analytical, respectively) functions of the index on this interval. This paper provides an example of analytical system whose solution set cannot be the solution set of any polynomial system.

Acute and chronic exposure to arsenic is a growing problem in the industrialized world. Arsenic is a potent carcinogen and toxin in humans. In the body, arsenic is metabolized to produce several species, including inorganic forms, such as trivalent (AsIII) and pentavalent (AsV), and the methylated metabolites such as monomethylarsonic acid, (MMAV), and dimethylarsinic acid (DMAV), in addition to arsenobetaine (AsB) which is ingested and excreted from the body in the same form. Each of these species has been reported to possess a specific but different degree of toxicity. Thus, not only is the measurement of total As required, but also quantification of the individual metabolites is necessary to evaluate the toxicity and risk assessment of this element. There are a large number of reference materials that are used to validate methodology for the analysis of As in blood and urine, but they are limited to total As concentrations. In this study, the speciation of five arsenic metabolites is reported in blood and urine from commercial available control materials certified for total arsenic levels. The separation was performed with an anion exchange column using inductively coupled plasma mass spectrometry as a detector. Baseline separation was achieved for AsIII, AsV, MMAV, DMAV, and AsB, allowing us to quantify all five species. Excellent agreement between the total arsenic levels and the sum of the speciated As levels was obtained.

A linear inequality system with infinitely many constraints is polynomial [analytical] if its index set is a compact interval of the real line and all its coefficients are polynomial [analytical] functions of the index on this interval. This paper provides sufficient conditions for a given closed convex set to be the solution set of a certain polynomial or at least analytical system.

We analyze the behavior of the feasible set in one class of semi-infinite optimization problems, inspired of an approximation of a given function, by means of functions belonging to a Haar space. We present a necessary and sufficient condition for the unicity of the approximation function from the Haar space. Continuity properties of the feasible set mapping have been investigated, as well.

In this paper we consider the space of all the linear semi-infinite programming problems with the same index set, endowed with a suitable topology. We provide a constructive proof of the following generic result: if we confine ourselves to the class of problems having a bounded set of coefficient vectors (those vectors appearing in the left-hand side of the constraints), the set of those problems which have a strongly unique optimal solution contains an open and dense subset of the set of solvable problems in the same class.

Using conventional breeding methods for obtaining the homozygous lines in segregated population takes a lot of time. This study presents the intensification achieved in the breeding process of wheat by application of embryo culture and dihaploidization on the material in intervarietal hybridization. Hybrids with high regeneration capacity at anther culture cultivation were obtained. For a considerably short period of 6-7 years large number of androgenic wheat lines were selected and analysed. Some of them combine valuable economic properties from both parental forms: higher yield and higher stem density. In the recent years these lines were used as initial breeding material for hybridization in Dobroudja Agricultural Institute. A candidate-variety was released, which exceeded both the initial parental forms and the standards by grain yield.

In this paper we introduce the concept of solving strategy for a linear semi-infinite programming problem, whose index set is arbitrary and whose coefficient functions have no special property at all. In particular, we consider two strategies which either approximately solve or exactly solve the approximating problems, respectively. Our principal aim is to establish a global framework to cope with different concepts of well-posedness spread out in the literature. Any concept of well-posedness should entail different properties of these strategies, even in the case that we are not assuming the boundedness of the optimal set. In the paper we consider three desirable properties, leading to an exhaustive study of them in relation to both strategies. The more significant results are summarized in a table, which allows us to show the double goal of the paper. On the one hand, we characterize the main features of each strategy, in terms of certain stability properties (lower and upper semicontinuity) of the feasible set mapping, optimal value function and optimal set mapping. On the other hand, and associated with some cells of the table, we recognize different notions of Hadamard well-posedness. We also provide an application to the analysis of the Hadamard well-posedness for a linear semi-infinite formulation of the Lagrangian dual of a nonlinear programming problem.

This paper deals with the stability of two families of linear optimization problems, each one formed by the dual problems to the members of the other family. We characterize the problems of these families that are stable in the sense that they remain consistent (inconsistent) under sufficiently small arbitrary perturbations of all the data. This characterization is established in terms of the lower semicontinuity property of the feasible set mapping and the boundedness of the optimal set of the corresponding coupled problem. Other continuity properties of the feasible set mapping are also derived. This stability theory extends some well-known theorems of Williams and Robinson on the stability of ordinary linear programming problems to linear optimization problems with infinitely many variables or constraints.

Biochemical and technological characteristics of twenty stabilized progenies of the crosses Pliska/Krasnodarskaya 39 and 4133–409/Odeskaya 76 were studied. Breadmaking quality characters and HMW glutenin subunits were investigated. The correlations between Glu-1 quality score and some qualitative features are statistically significant. HMW glutenin subunits 5+10 controlled by Glu-D1 locus demonstrated the highest effect on qualitative characteristics followed by subunit 2* controlled by the Glu-A1 locus.

Breadmaking quality characterization of wheat genotypes is a widely used approach to evaluate breeding material. Biochemical data on storage proteins describe their nutritive value, and to some extent they are related to their baking performance. A group of recently created high bread quality wheat cultivars and lines Shabla, 2571-65-4, 2579-30, 12-11-19, 4-P2-3, 7-P2-6,14-P2-4,18-P2-4, 24-F-8, Pliska, Slavyanka 196 and Sadovo 1 is the subject of this study.The total protein content of 70% flour, amino-acid composition, Osborn extraction fractions and HMW glutenin subunits are investigated. The data received by now show a similar amino acid composition between the genotypes investigated although in many cases the differences are statistically significant concerning some amino acids. The total essential amino acid level in eight of investigated genotypes is lower than that of cultivar Sadovo 1 and correlates negatively to their higher total protein content. Statistically significant total protein content correlates with sedimentation value, wet gluten and loaf volume, globulins correlate with dough stability and farinograph value, gliadins - with wet gluten and loaf volume, while glutenins correlate with sedimentation value, wet gluten, dough stability and farinograph value. HMW glutenin subunits are in a good accordance with sedimentation value.

We consider parametric semi-infinite optimization problems without the usual asssumptions on the continuity of the involved mappings and on the compactness of the index set counting the inequalities. We establish a characterization of those optimization problems which have a unique or strongly unique solution and which are stable under small pertubations. This result generalizes a well-known theorem of Nurnberger. The crucial roles in our investigations are a new concept of active constraints, a generalized Slater's condition, and a Kuhn—Tucker-type theorem. Finally, we give some applications in vector optimization, for approximation problems in normed spaces, and in the stability of the minimal value.

This paper deals with the conditions for the uniqueness of the optimal solution of an optimization problem for which the objective function is linear and the feasible set is a closed convex set in a finite-dimensional space. Some of these conditions, such as strong unicity andw-unicity (a new transition concept), involve only the feasible set. Others are related to the properties of the chosen linear representation. To some extent, the paper surveys the literature about unicity and strong unicity in linear semi-infinite programming.