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Accurate results with analytical solution to standard concentration ratios less than 10.

Arsenic was speciated in 46 seaweed samples purchased from the U.S. market, i.e., brown (arame, hijiki, kombu, knotted wrack, oarweed, wakame), green (sea lettuce), and red (dulse, Irish moss, lave...

We present the development and optimization of an analytical method based on Laser Ablation–Inductively Coupled Plasma–Mass Spectrometry (LA-ICP-MS) for the analysis of multivitamin dietary supplements. Samples were ground and mixed with a cellulose powder containing internal standard elements; the resulting powder was pressed into pellets. Two calibration strategies were compared: (1) using increasing mass fractions of cellulose powder fortified with multiple elements of interest, and (2) matrix matching using a multivitamin reference material in addition to the multi-element cellulose powder. Laser and ICP-MS parameters were closely monitored to produce the best signal while reducing the variability between replicate measurements. An energy output of 0.5 J/cm2, a repetition rate of 30 Hz, and a He carrier gas flow rate of 800 mL/min provided the best compromise between sensitivity and reproducibility. These parameters produced the most similar ablation behavior between cellulose and a matrix-matched calibration strategy. The dissimilarities in ablation yield due to differences in focal points were successfully corrected after normalizing to an internal standard, resulting in relative differences of less than 10%. The results from the two different calibration approaches were compared to those obtained from solution ICP-MS and Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) analyses. For most multivitamins, both calibration methods (i.e., cellulose and matrix-matched calibrations) performed adequately for As, B, Co, Cr, Cu, Mg, Ni, Na, Pb, and Zn. Matrix-matched calibration additionally resulted in better recoveries for S and Fe. Overall, matrix-matched calibration resulted in better recoveries for more multivitamins in comparison with cellulose calibration.

In this study we present an elemental profile of 46 edible seaweed samples purchased in the United States. The seaweeds were grouped in 13 subgroups/species based on DNA barcoding analysis. The seaweeds were decomposed by microwave accelerated acid digestion followed by quantification of 26 elements by ICP-MS. Elements were grouped into macronutrient (Na, K, Ca, S, Mg and P), essential (Fe, Zn, Mn, V, Cu, Cr, Ni, Mo and Se), non-essential including toxic elements (Sr, Ba, Th, Sn and Sb As, Cd, Pb, U, W and Hg). The highest levels were found for Na and the lowest were for Hg. The elemental profiles depended on the taxonomy of the species and several elements (Fe, Ba, Cr, Pb, W and Th) also exhibited high intraspecies variations, likely due to geographic origin or food processing conditions. Higher Cd and Pb accumulation was observed in wakame, hijiki and nori, with Cd as high 4.05 mg/kg and Pb as high as 2.85 mg/kg in kombu. A study of correlation between the elements using Pearson's coefficients revealed multiple pairs of highly correlated elements in seaweed, as well as triple and quintuple correlations of certain elements.

Rice is a staple food in many countries around the world and it is a source of not only the nutrients, but also toxic elements. In this study, we evaluated four degrees of polishing and determined the elemental content (P, S, K, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, Cd, Hg, Pb) in brown rice, rice bran and the resulting white rice using microwave assisted decomposition followed by inductively coupled plasma mass spectrometry (ICP-MS) detection. Additionally, individual rice grains at every polishing step were analyzed by laser ablation ICP-MS to generate elemental distribution maps. While P, K, Mn and Fe were predominantly located in bran layer, S, Cu, Zn, As, Se, Mo, Cd, and Hg were present in both the bran and endosperm. As the elemental distribution in the grain varies, polishing to produce white rice results in removal of different amounts of nutrient and toxic elements.

The effect of antihomotoxic prepapation Traumel on the clinical condition, morphological, biochemical and immunological parameters of blood and blood serum of clinically healthy dogs is determined in the article on the basis of experimental studies. The problem of using antihomotoxyc preparations for the treatment of animal diseases is one of the most controversial issues in modern clinical medicine, but there is growing interest in finding alternative treatments in the world. Today there is a number of research and publications claiming that complex anthyhomotoxyc preparations have a correcting effect. Some scientists talk about the immunostimulatory effect of anthyhomotoxyc preparations. However, all of these studies were conducted mainly in humane medicine and in laboratory animals. Thorough studies of the effects of the anthyhomotoxyc preparation Traumel on the organism of clinically healthy dogs have not been conducted previously. Therefore, this work is relevant and timely. The purpose of our work is to study the effect of complex anthyhomotoxyc preparation Traumel on clinically healthy animals. The material for the study was a group of ten clinically healthy dogs, which before the use of anthyhomotoxyc preparation were determined based on the clinical condition, morphological, biochemical and immunological parameters of their blood. Then we injected the preparation. The preparations were given in a dose of 1 ml per animal per day. Blood and blood serum tests were performed on the first, third, sixth and thirtieth days. The results were compared with those obtained during the determination of the state of the organism before the preparation use. Laboratory studies were conducted at the laboratory of the Odessa Regional Clinical Hospital. The results of our research show that complex antigomotoxicin preparation Traumel has a moderate effect on the body of clinically healthy dogs, which has no pronounced clinical manifestations. Blood and blood serum levels do not go beyond physiological limits.

Foreign body giant cell (FBGC) reaction to silicone material in the lymph nodes of patients with silicone breast implants has been documented in the literature, with a number of case reports dating back to 1978. Many of these case reports describe histologic features of silicone lymphadenopathy in regional lymph nodes from patients with multiple sets of different types of implants, including single lumen smooth surface gel, single lumen textured surface gel, single lumen with polyethylene terephthalate patch, single lumen with polyurethane coating, and double lumen smooth surface. Only one other case report described a patient with highly-cohesive breast implants and silicone granulomas of the skin. In this article, we describe a patient with a clinical presentation of systemic sarcoidosis following highly cohesive breast implant placement. Histopathologic analysis and Confocal Laser Raman Microprobe (CLRM) examination were used to confirm the presence of silicone in the axillary lymph node and capsular tissues. This is the first report where chemical spectroscopic mapping has been used to establish and identify the coexistence of Schaumann bodies, consisting of calcium oxalate and calcium phosphate minerals, together with silicone implant material.

J. E. Martínez-Legaz was partially supported by the MINECO of Spain, Grant MTM2014-59179-C2-2-P, the Severo Ochoa Programme for Centres of Excellence in R&D [SEV-2015-0563], and under the Australian Research Council's Discovery Projects funding scheme (project number DP140103213). He is affiliated with MOVE (Markets, Organizations and Votes in Economics). M. I. Todorov was partially supported by the MINECO of Spain and ERDF of EU, Grant MTM2014-59179-C2-1-P, and Sistema Nacional de Investigadores, Mexico. Altres ajuts: Australian Research Council DP140103213 We introduce and study the class of weakly Motzkin predecomposable sets, which are those sets in ℝ n that can be expressed as the Minkowski sum of a bounded convex set and a convex cone, none of them being necessarily closed. This class contains that of Motzkin predecomposable sets, for which the bounded components are compact, which in turn contains the class of Motzkin decomposable sets, for which the bounded components are compact and the conic components are closed.

The problem of finding a feasible solution to a linear inequality system arises in numerous contexts. In Gonzalez-Gutierrez and Todorov (Optim. Lett. doi:10.1007/s11590-010-0244-4, 2011), an algorithm, called extended relaxation method, for solving the feasibility problem has been proposed by the authors. Convergence of the algorithm has been proven. In this paper, we consider a class of extended relaxation methods depending on a parameter and prove their convergence. Numerical experiments have been provided, as well.

In this article, we extend the definition of γ-active constraints for linear semi-infinite programming to a definition applicable to convex semi-infinite programming, by two approaches. The first approach entails the use of the subdifferentials of the convex constraints at a point, while the second approach is based on the linearization of the convex inequality system by means of the convex conjugates of the defining functions. By both these methods, we manage to extend the results on γ-active constraints from the linear case to the convex case.

Many medical devices contain metals that interface with the body. Additionally, embedded metal fragments from military wounds are typically not removed, to avoid the risk of morbidity associated with invasive surgery. The long-term health consequences of many of these materials are not thoroughly understood. To this end, we have exposed rats for up to one year to implanted single-element metal pellets of any one of Al, Co, Cu, Fe, Ni, Pb, Ta, or W. Various tissues were harvested and flash frozen for analysis of their metal distribution. We discuss approaches to most thoroughly and reliably evaluate the distribution of metal in these tissues. The path to the most appropriate analytical technique took us through extensive examination of the tissues using scanning electron microscopy with energy dispersive X-ray spectroscopy (XPS), X-ray photoelectron spectroscopy (XPS), and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Though any one of these methods is highly relied upon in surface chemistry analysis, LA-ICP-MS alone showed presence of metal in the tissue. This information will help build robust methods to bridge the gap in our understanding of biosolubility and distribution of embedded metal throughout the body.

Background: Trigeminal neuralgia (TN) is a severe, disabling form of painful cranial neuropathy. Even though TN has a typical clinical picture, diagnosis it is often missed or delayed in clinical practice. In order to investigate the occurrence of diagnostic and therapeutic errors in TN, we studied 102 patients suffering from TN recruited through a multicentric survey. Methods: We performed a Pubmed database search on errors and pittfalls in TN diagnosis and management. Then, patients with TN were consecutively enrolled in the period from February 2017 to October 2019, by several European Headache Centers participating in the study, following a call of the Headache and Pain Scientific Panels of the European Academy of Neurology (EAN). Diagnosis of Classical Trigeminal Neuralgia (CTN) was made according to the International Headache Society (IHS) criteria (Tölle et al., Pain Pract 6:153-160, 2006). All the patients were evaluated using telephone/frontal interviews conducted by headache/pain specialists using an ad hoc questionnaire. Results: A number of 102 patients were recruited, mostly females (F:M ratio 2.64:1). Eighty-six percent of the patients consulted a physician at the time they experienced the first pain attacks. Specialists consulted before TN diagnosis were: primary care physicians (PCP) (43.1%), dentists (in 30.4%), otorhinolaryngologists (3.9%), neurosurgeons (3.9%), neurologists or headache specialists (14.7%), others (8%). The final diagnosis was made mainly by a neurologist or headache specialist (85.3%), and the mean interval between the disease onset and the diagnosis made by a specialist was 10.8 ± 21.2 months. The "diagnostic delay"was 7.2 ± 12.5 months, and misdiagnoses at first consultation were found in 42.1% of cases. Instrumental and laboratory investigations were carried out in 93.1% of the patients before the final diagnosis of TN. Conclusion: While TN has typical features and it is well defined by the available international diagnostic criteria, it is still frequently misdiagnosed and mistreated. There is a need to improve the neurological knowledge in order to promptly recognize the clinical picture of TN and properly adhere to the specific guidelines. This may result in a favorable outcome for patients, whose quality of life is usually severely impaired. © 2020 The Author(s).

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.

Humans accumulate large numbers of inorganic particles in their lungs over a lifetime. Whether this causes or contributes to debilitating disease over a normal lifespan depends on the type and concentration of the particles. We developed and tested a protocol for in situ characterization of the types and distribution of inorganic particles in biopsied lung tissue from three human groups using field emission scanning electron microscopy (FE-SEM) combined with energy dispersive spectroscopy (EDS). Many distinct particle types were recognized among the 13 000 particles analyzed. Silica, feldspars, clays, titanium dioxides, iron oxides and phosphates were the most common constituents in all samples. Particles were classified into three general groups: endogenous, which form naturally in the body; exogenic particles, natural earth materials; and anthropogenic particles, attributed to industrial sources. These in situ results were compared with those using conventional sodium hypochlorite tissue digestion and particle filtration. With the exception of clays and phosphates, the relative abundances of most common particle types were similar in both approaches. Nonetheless, the digestion/filtration method was determined to alter the texture and relative abundances of some particle types. SEM/EDS analysis of digestion filters could be automated in contrast to the more time intensive in situ analyses.

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).

Motor adaptation to perturbations is provided by learning mechanisms operating in the cerebellum and basal ganglia. The cerebellum normally performs motor adaptation through supervised learning using information about movement error provided by visual feedback. However, if visual feedback is critically distorted, the system may disengage cerebellar error-based learning and switch to reinforcement learning mechanisms mediated by basal ganglia. Yet, the exact conditions and mechanisms of cerebellum and basal ganglia involvement in motor adaptation remain unknown. We use mathematical modeling to simulate control of planar reaching movements that relies on both error-based and non-error-based learning mechanisms. We show that for learning to be efficient only one of these mechanisms should be active at a time. We suggest that switching between the mechanisms is provided by a special circuit that effectively suppresses the learning process in one structure and enables it in the other. To do so, this circuit modulates learning rate in the cerebellum and dopamine release in basal ganglia depending on error-based learning efficiency. We use the model to explain and interpret experimental data on error- and non-error-based motor adaptation under different conditions.

Background: The performance of U.S. Food and Drug Administration (FDA) Elemental Analysis Manual (EAM) 4.13 method (Inductively Coupled Plasma-Mass Spectrometric Determination of Iodine in Food Using Tetramethyl Ammonium Hydroxide Extraction) was tested in an interlaboratory study. Objective: The aim of the study is to demonstrate that the FDA EAM method 4.13 is applicable for the analysis of food and multivitamins. Methods: Six collaborators participated in the study using four different models of inductively coupled plasma-mass spectrometry instruments. The method evaluation included determination of the limits of detection and quantification, analysis of National Institute of Standards and Technology standard reference materials (SRMs), unknown samples, blinded SRMs, and fortified analytical portions by all six collaborators. The samples were chosen to represent all sectors of the AOAC food triangle and additionally included pet food and multivitamin tablets. Results: The repeatability and reproducibility ranges were 1.8–11.4% and 3.6–13.7%, respectively; the calculated HorRat values were in the 0.17–1.18 range; and 174 of 175 SRM analyses had z-scores

Given an arbitrary set Tin the Euclidean space Rn, whose elements are called sites, and a particular site s, the farthest Voronoi cell of s, denoted by FT(s), consists of all points which are farther from s than from any other site. In this paper we study farthest Voronoi cells and diagrams corresponding to arbitrary (possibly infinite) sets. More in particular, we characterize, for a given arbitrary set T, those s ∈T such that FT(s) is nonempty and study the geometrical properties of FT(s) in that case. We also characterize those sets Twhose farthest Voronoi diagrams are tesselations of the Euclidean space, and those sets that can be written as FT(s) for some T⊂Rn and some s ∈T. The first and second author were supported by Ministry of Science, Innovation and Universities of Spain and the European Regional Development Fund (ERDF) of the European Commission, Grants PGC2018-097960-B-C22 and PGC2018-097960-B-C21, respectively. The second author was also supported by the Severo Ochoa Programme for Centres of Excellence in R&D [SEV-2015-0563].

Novel treatments in mental health focus on one’s ability to recover and develop resilience. Current concepts are based on The Adaptations Level Theory, which describes the ability of resilient individuals to accustom to new and even downgraded conditions as the new standard, find meaning in trauma, and adapt to new social settings. However, it is not known which treatments specifically help to build up resilience in patients and how to reliably screen for it. Recent studies demonstrated that distinct patterns of language use correlated with various mental health conditions. Utilizing text samples from the Holocaust survivors, we studied language use in resilient individuals compares to people with PTSD and general population. Holocaust survivors' language use was significantly different from PTSD sufferers, which suggests that we detected a possible resilience word use pattern. Next, we looked into the brain circuitry mechanisms that could be involved in resilience. We found that norepinephrine, the key neurotransmitter in stress response, modulated the activity of amygdala circuitry in a non-linear concentration-dependent manner. The shape and other characteristics of this dependency could be associated with the capacity for resilience.

We consider two partitions over the space of linear semi-infi nite programming parameters with a fi xed index set and bounded coefficients (the functions of the constraints are bounded). The fi rst one is the primal-dual partition inspired by consistency and boundedness of the optimal value of the linear semi-infi nite optimization problems. The second one is a re finement of the primal-dual partition that arises considering the boundedness of the optimal set. These two partitions have been studied in the continuous case, this is, the set of indices is a compact infi nite compact Hausdorff topological space and the functions de fining the constraints are continuous. In this work, we present an extension of this case. We study same topological properties of the cells generated by the primal-dual partitions and characterize their interior. Through examples, we show that the results characterizing the sets of the partitions in the continuous case are neither necessary nor sufficient in both refi nements. In addition, a sufficient condition for the boundedness of the optimal set of the dual problem has been presented.

In this study, we explore the functional role of striatal cholinergic interneurons, hereinafter referred to as tonically active neurons (TANs), via computational modeling; specifically, we investigate the mechanistic relationship between TAN activity and dopamine variations and how changes in this relationship affect reinforcement learning in the striatum. TANs pause their tonic firing activity after excitatory stimuli from thalamic and cortical neurons in response to a sensory event or reward information. During the pause striatal dopamine concentration excursions are observed. However, functional interactions between the TAN pause and striatal dopamine release are poorly understood. Here we propose a TAN activity-dopamine relationship model and demonstrate that the TAN pause is likely a time window to gate phasic dopamine release and dopamine variations reciprocally modulate the TAN pause duration. Furthermore, this model is integrated into our previously published model of reward-based motor adaptation to demonstrate how phasic dopamine release is gated by the TAN pause to deliver reward information for reinforcement learning in a timely manner. We also show how TAN-dopamine interactions are affected by striatal dopamine deficiency to produce poor performance of motor adaptation.

The Hideaway Park tuff is the only preserved extrusive volcanic unit related to the Red Mountain intrusive complex, which produced the world-class Henderson porphyry Mo deposit. Located within the Colorado Mineral Belt, USA, Henderson is the second largest Climax-type Mo deposit in the world, and is therefore an excellent location to investigate magmatic processes leading to Climax-type Mo mineralization. We combine an extensive dataset of major element, volatile, and trace element abundances in quartz-hosted melt inclusions and pumice matrix glass with major element geochemistry from phenocrysts to reconstruct the pre-eruptive conditions and the source and evolution of metals within the magma. Melt inclusions are slightly peraluminous topaz rhyolitic in composition and are volatile-charged (� 6w t % H2O, � 600 ppm CO2, � 0� 3–1� 0w t % F, � 2300–3500 ppm Cl) and metal-rich (� 7–24 ppm Mo, � 4–14 ppm W, � 21–52 ppm Pb, � 28–2700 ppm Zn

The problem (LFP) of finding a feasible solution to a given linear semi-infinite system arises in different contexts. This paper provides an empirical comparative study of relaxation algorithms for (LFP). In this study we consider, together with the classical algorithm, implemented with different values of the fixed parameter (the step size), a new relaxation algorithm with random parameter which outperforms the classical one in most test problems whatever fixed parameter is taken. This new algorithm converges geometrically to a feasible solution under mild conditions. The relaxation algorithms under comparison have been implemented using the extended cutting angle method for solving the global optimization subproblems. This research was partially supported by MICINN of Spain, Grant MTM2014-59179-C2-1-P and Sistema Nacional de Investigadores, Mexico.

To evaluate whether anatectic and/or highly fractionated lithophile element-enriched rhyolite tuffs deposited in arid lacustrine basins lose enough lithium during eruption, lithification, and weathering to generate significant Li brine resources, pre-eruptive melt compositions, preserved in inclusions, and the magnitude of post-eruptive Li depletions, evident in host rhyolites, were documented at six sites in the western United States. Each rhyolite is a member of the bimodal basalt-rhyolite assemblage associated with extensional tectonics that produced the Basin and Range province and Rio Grande rift, an evolving pattern of closed drainage basins, and geothermal energy or mineral resources. Results from the 0.8 Ma Bishop tuff (geothermal) in California, 1.3 to 1.6 Ma Cerro Toledo and Upper Bandelier tephra (geothermal) and 27.9 Ma Taylor Creek rhyolite (Sn) in New Mexico, 21.7 Ma Spor Mountain tuff (Be, U, F) and 24.6 Ma Pine Grove tuff (Mo) in Utah, and 27.6 Ma Hideaway Park tuff (Mo) in Colorado support the following conclusions. Melt inclusions in quartz phenocrysts from rhyolite tuffs associated with hydrothermal deposits of Sn, Mo, and Be are extremely enriched in Li (1,000s of ppm); those from Spor Mountain have the highest Li abundance yet recorded (max 5,200 ppm, median 3,750 ppm). Forty-five to 98% of the Li present in pre-eruptive magma was lost to the environment from these rhyolite tuffs. The amount of Li lost from the small volumes (1–10 km3) of Li-enriched rhyolite deposited in closed basins is sufficient to produce world-class Li brine resources. After each eruption, meteoric water leaches Li from tuff, which drains into playas, where it is concentrated by evaporation. The localized occurrence of Li-enriched rhyolites may explain why brines in arid lacustrine basins seldom have economic concentrations of Li. Considering that hydrothermal deposits of Sn, Mo, Be, U, and F may indicate potential for Li brines in nearby basins, we surmise that the world’s largest Li brine resource in the Salar de Uyuni (10 Mt) received Li from nearby rhyolite tuffs in the Bolivian tin belt.

The effects of EDTA application to heavy metal-polluted soil on phytoextraction of heavy metals, leaf anatomy, gas exchange parameters, enzyme activities of C4 carbon cycle, antioxidant defense, and active compounds of Tribulus terrestris L. were evaluated. The addition of EDTA to the soil polluted with Cd and Pb markedly increased dry weight and Pb, Zn, and Cd contents in shoots. Plants responded to the action of EDTA by an increased stomatal conductance, photosynthetic and transpiration rates, water use efficiency, chlorophyll and carotenoid contents. The activities of C4 carbon cycle enzymes simultaneously increased, thus concentrating CO2 for enhanced CO2 assimilation and providing NADPH for the antioxidant system. Antioxidants, such as ascorbate, reduced glutathione, and flavonoids, increased more in the shoots of T. terrestris after the addition of EDTA. The activities of guaiacol peroxidase, catalase, and the enzymes of the ascorbate-glutathione cycle enhanced significantly in the presence of EDTA. Increased activities of antioxidant enzymes suggest that they have some additive functions in the mechanism of metal tolerance. EDTA application lowered the activity of phenylalanine ammonia-lyase and the content of total phenols, MDA, hydrogen peroxide, dehydroascorbate, and lipid-soluble antioxidant capacity expressed as α-tocopherol. Increased levels of total radical-scavenging activity are in correspondence with the activity of water-soluble antioxidant compounds in T. terrestris tissues. The content of furostanol saponins protodioscin, prototribestin, and rutin increased as a result of EDTA addition. The results obtained allowed us to assume that applied EDTA reduced a negative heavy metal impact on puncture vine photosynthesis and antioxidant potential.

Linear vector semi-infinite optimization deals with the simultaneous minimization of finitely many linear scalar functions subject to infinitely many linear constraints. This paper provides characterizations of the weakly efficient, efficient, properly efficient and strongly efficient points in terms of cones involving the data and Karush–Kuhn–Tucker conditions. The latter characterizations rely on different local and global constraint qualifications. The global constraint qualifications are illustrated on a collection of selected applications. This research was partially supported by MICINN of Spain, Grant MTM2011-29064-C03-02 and CONACYT of Mexico, Grant 55681. The first author is Partner Investigator in the Australian Research Council Discovery Project DP120100467.

The US Antimony mine in west central Montana is the United States' second largest quartz–stibnite vein deposit with production and reserves of about 15.4 kt of antimony. It is in the Mesoproterozoic Belt Basin on the eastern side of the Coeur d'Alene mining district that is known for its world class Ag, Pb, and Zn veins. To advance understanding of the origin and relation of the simple quartz–stibnite veins in the Prichard Formation to the giant Ag-rich tetrahedrite veins in the Revett and St. Regis Formations, fluid inclusions in quartz from the US Antimony mine were characterized using a variety of single inclusion and bulk analysis techniques. The measured Sb concentrations in fluid inclusions (approximately 2000 ppm) agree with equilibrium models for stibnite-saturated fluids at the measured homogenization temperatures (224–263°C), salinities (approximately 5 wt.% NaCl), H2S concentrations ( As > Fe > Pb > Zn > Cu > Ag) in fluid inclusions from the US Antimony mine support previous interpretations, based upon Pb isotopes, that the quartz–stibnite veins are genetically related to the Ag-rich tetrahedrite veins. In particular, the measured range of Ag concentrations in US Antimony fluid inclusions brackets that calculated on the basis of equilibrium with tetrahedrite in the silver veins. These data clearly show that hydrothermal fluids in the Prichard Formation contained metals that were fixed at shallower levels in the Revett and St. Regis Formations. We surmise that both the antimony and silver veins formed in response to Cretaceous magmatism, prograde metamorphism of the lower Prichard Formation, and episodic discharge of metamorphic fluids along dilatant faults. Ascending fluids deposited quartz and stibnite in the upper Prichard Formation and siderite, quartz, and tetrahedrite at shallower levels in the Revett and St. Regis Formations in response to cooling, decompression, phase separation, and mixing with external fluids.

A nonempty set F is called Motzkin decomposable when it can be expressed as the Minkowski sum of a compact convex set C with a closed convex cone D. In that case, the sets C and D are called compact and conic components of F. This paper provides new characterizations of the Motzkin decomposable sets involving truncations of F (i.e., intersections of FF with closed halfspaces), when F contains no lines, and truncations of the intersection F̂ of F with the orthogonal complement of the lineality of F, otherwise. In particular, it is shown that a nonempty closed convex set F is Motzkin decomposable if and only if there exists a hyperplane H parallel to the lineality of F such that one of the truncations of F̂ induced by H is compact whereas the other one is a union of closed halflines emanating from H. Thus, any Motzkin decomposable set F can be expressed as F=C+D, where the compact component C is a truncation of F̂. These Motzkin decompositions are said to be of type T when F contains no lines, i.e., when C is a truncation of F. The minimality of this type of decompositions is also discussed. This work has been supported by the MICINN of Spain, Grants MTM2011-29064-C03-01&02, by the Barcelona Graduate School of Economics, by the Government of Catalonia, by CONACyT of Mexico, Grant 55681, and by CNPq of Brazil, Grant 301280/86. The first author is Partner Investigator in the Australian Research Council Discovery Project DP120100467. The third author is affiliated toMOVE(Markets, Organizations and Votes in Economics).

In this study we report uranium analysis for human semen samples. Uranium quantification was performed by inductively coupled plasma mass spectrometry. No additives, such as chymotrypsin or bovine serum albumin, were used for semen liquefaction, as they showed significant uranium content. For method validation we spiked 2g aliquots of pooled control semen at three different levels of uranium: low at 5 pg/g, medium at 50 pg/g, and high at 1000 pg/g. The detection limit was determined to be 0.8 pg/g uranium in human semen. The data reproduced within 1.4-7% RSD and spike recoveries were 97-100%. The uranium level of the unspiked, pooled control semen was 2.9 pg/g of semen (n=10). In addition six semen samples from a cohort of Veterans exposed to depleted uranium (DU) in the 1991 Gulf War were analyzed with no knowledge of their exposure history. Uranium levels in the Veterans' semen samples ranged from undetectable (0.8 pg/g) to 3350 pg/g. This wide concentration range for uranium in semen is consistent with known differences in current DU body burdens in these individuals, some of whom have retained embedded DU fragments.

Convex vector (or multi-objective) semi-infinite optimization deals with the simultaneous minimization of finitely many convex scalar functions subject to infinitely many convex constraints. This paper provides characterizations of the weakly efficient, efficient and properly efficient points in terms of cones involving the data and Karush–Kuhn–Tucker conditions. The latter characterizations rely on different local and global constraint qualifications. The results in this paper generalize those obtained by the same authors on linear vector semi-infinite optimization problems.

Arsenic (As) is a well documented human carcinogen. However, its mechanisms of toxic action and carcinogenic potential in animals have not been conclusive. In this research, we investigated the biochemical and genotoxic effects of As and studied its distribution in selected tissues of Sprague-Dawley rats. Four groups of six male rats, each weighing approximately 60 ± 2 g, were injected intraperitoneally, once a day for 5 days with doses of 5, 10, 15, 20 mg/kg bw of arsenic trioxide. A control group was also made of 6 animals injected with distilled water. Following anaesthetization, blood was collected and enzyme analysis was performed by spectrophotometry following standard protocols. At the end of experimentation, the animals were sacrificed, and the lung, liver, brain and kidney were collected 24 h after the fifth day treatment. Chromosome and micronuclei preparation was obtained from bone marrow cells. Arsenic exposure significantly increased (p

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. In E. Gonzalez-Gutierrez and M.I. Todorov [A relaxation method for solving systems with infinitely many linear inequalities, Optim. Lett. DOI: 10.1007/s11590-010-0244-4] an algorithm, called extended relaxation method (ERM), which solves the feasibility problem has been proposed. Later in E. Gonzalez-Gutierrez, L. Hernandez Rebollar, and M.I. Todorov [Relaxation methods for solving linear inequality systems: Converging results, preprint, CMR, 990 (2011), pp. 1–9], we consider a class of algorithms, depending on a parameter and prove their convergence. In this article, for the same class of the ERMs a linear rate of convergence is obtained.

Background: There are many studies on prostate cancer incidence and exposure to heavy metals such as cadmium, iron, selenium and zinc. Much less data is available on the possible influence of heavy metals on prostate cancer outcome. We and others have shown that cadmium, iron and zinc exposure in vitro can cause changes in cell invasion. Recently we have published an inductively coupled plasma-mass spectrometry (ICP-MS) method to reliably measure concentration of these metals in paraffin embedded archival tissues. Here we study the level of these ions in the prostate of patients with known outcome in order to address metals and disease progression. Methods: The source of tissues Cooperative Prostate Cancer Tissue Resource (CPCTR). We obtained formalin fixed paraffin embedded tissue blocks of prostatectomy samples of 40 patients with PSA recurrence, matched 1:1 (for year of surgery, race, age, Gleason grading score and stage) with tissue blocks from 40 patients without recurrence (n=80). All non-recurrence patients had more than 5-years post-prostatectomy follow-up. Case-control pairs were compared for the levels of heavy metals in areas adjacent to tumors. After deparaffinization, each tissue sample was oven-dried and divided in 5-10 µg triplicates. Internal standards were added (Y and 74Se), digested overnight in nitric acid. ICP-MS was performed by comparing samples with standard solutions of each analyte (Cd, Fe, Zn, and Se). The association of each individual metal with prostate cancer recurrence was evaluated by Wilcoxon signed rank paired test comparing matched recurrence cases and non-recurrence control cases. Results: Patients with biochemical (PSA) recurrence of disease had 14% lower iron [95 vs. 112 parts per million (ppm); p = 0.04] and 9% lower zinc (28 vs. 35 ppm; p = 0.04) concentrations in the normal-appearing tissue immediately adjacent to prostate cancer areas. Differences in cadmium [488 vs. 439 parts per billion (ppb); 10% higher) and selenium (1676 vs. 1576 ppb; 6% higher] levels were not statistically significant in recurrence cases when compared to non-recurrences (p=0.40 and 0.21 respectively). Discussion: To the best of our knowledge this is the first study to show an association between metal tissue levels and outcomes in prostate cancer. Lower zinc in cases of worse outcome suggests this may be an area for further investigation in recurrence chemoprevention. Lower iron may be the result of iron sequestration in the reticuloendothelial system caused by aggressive cancer, rather than a factor important for prostate cancer progression, a hypothesis that needs further investigation. The lack of association of recurrence with either cadmium or selenium was an unexpected finding.

A set is called Motzkin decomposable when it can be expressed as the Minkowski sum of a compact convex set with a closed convex cone. The main result in this paper establishes that a closed convex set is Motzkin decomposable if and only if the set of extreme points of its intersection with the linear subspace orthogonal to its lineality is bounded. The paper characterizes the class of the extended functions whose epigraphs are Motzkin decomposable sets showing, in particular, that these functions attain their global minima when they are bounded from below. Calculus of Motzkin decomposable sets and functions is provided. This work has been supported by MICINN of Spain, Grants MTM2008-06695-C03-01/03, by Generalitat Valenciana, by Generalitat de Catalunya, by the Barcelona GSE Research Network, and by CONACyT of Mexico, Grant 55681.

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.

Theodore Motzkin proved, in 1936, that any polyhedral convex set can be expressed as the (Minkowski) sum of a polytope and a polyhedral convex cone. This paper provides five characterizations of the larger class of closed convex sets in finite dimensional Euclidean spaces which are the sum of a compact convex set with a closed convex cone. These characterizations involve different types of representations of closed convex sets as the support functions, dual cones and linear systems whose relationships are also analyzed in the paper. The obtaining of information about a given closed convex set F and the parametric linear optimization problem with feasible set F from each of its different representations, including the Motzkin decomposition, is also discussed. This work has been supported by MICINN of Spain, Grants MTM2008-06695-C03-01/03, by Generalitat Valenciana, by Generalitat de Catalunya, by the Barcelona GSE Research Network, and by CONACyT of Mexico, Grant 55681.