1,535 research outputs found

    Local maximizers of generalized convex vector-valued functions

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    Any local maximizer of an explicitly quasiconvex real-valued function is actually a global minimizer, if it belongs to the intrinsic core of the function's domain. In this paper we show that similar properties hold for componentwise explicitly quasiconvex vector-valued functions, with respect to the concepts of ideal, strong and weak optimality. We illustrate these results in the particular framework of linear fractional multicriteria optimization problems.Any local maximizer of an explicitly quasiconvex real-valued function is actually a global minimizer, if it belongs to the intrinsic core of the function's domain. In this paper we show that similar properties hold for componentwise explicitly quasiconvex vector-valued functions, with respect to the concepts of ideal, strong and weak optimality. We illustrate these results in the particular framework of linear fractional multicriteria optimization problems

    KrP laser CVD of chromium oxide by photodissociation of Cr(CO)(6)

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    This work reports on the synthesis of chromium oxide thin films prepared by photodissociation of Cr(CO)(6) in an oxidizing atmosphere, using a pulsed UV laser (KrF, lambda = 248 nm). The experimental conditions, which should enable the synthesis of CrO2, are discussed and results on the deposition of CrxOy films on Al2O3 (0001) substrates are presented

    Phase growth control in low temperature PLD Co: TiO2 films by pressure

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    This paper reports on the structural and optical properties of Co-doped TiO2 thin films grown onto (0001)Al2O3 substrates by non-reactive pulsed laser deposition (PLD) using argon as buffer gas. It is shown that by keeping constant the substrate temperature at as low as 310 degrees C and varying only the background gas pressure between 7 Pa and 70 Pa, it is possible to grow either epitaxial rutile or pure anatase thin films, as well as films with a mixture of both polymorphs. The optical band gaps of the films are red shifted in comparison with the values usually reported for undoped TiO2, which is consistent with n-type doping of the TiO2 matrix. Such band gap red shift brings the absorption edge of the Co-doped TiO2 films into the visible region, which might favour their photocatalytic activity. Furthermore, the band gap red shift depends on the films' phase composition, increasing with the increase of the Urbach energy for increasing rutile content. (C) 2012 Elsevier B.V. All rights reserved

    Early and late changes of multi-marker panel in patients with STEMI after angioplasty

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    Background: Post-infarction remodeling is strongly linked with collagen turnover which is influenced mostly by oxidative stress and inflammation, the last being, according to our previous data, triggered by early infiltrated neutrophils (24–48 h) followed by accumulation of macrophages M1 (72 h) and M2 (7–14 days). Aim: Evaluation of circulating markers of inflammation and oxidative stress in the different periods of 1 year follow up post-infarct evolution: first 2 weeks (each day), 1st month (synthesis of collagen type III), 3rd month (synthesis of collagen type I), 6 and 12 months. Material and methods: Study was performed in 47 patients (age range of 37–68 years) with STEMI exposed to angioplasty (<12 hours). Circulating levels of 28 markers were determined at admission, 1, 2, 3 ... 14 days, 1, 3, 6 and 12 months. Obtained results were compared with control value of markers determined in 17 apparently healthy persons and admission level (before PCI). Results: The earliest (first 24 h) significant change was inherent to MMP-8, whose double elevation (averagely from 3,1 up to 6,4 ng/ml) corresponded to period of neutrophil infiltration (24–48 h). Serum levels of IL-1, IL-6 have raised significantly since 48 h, followed by authentic increase of TNF-alpha, IL-8, CRPhs and phospholipase A2 since 72 h. Up to a period of 7 days these markers remained increased, but toward 14th day fell by 24–46% arguably due to macrophage M2 activation. This is consistent to dynamics of anti-inflammatory markers, IL-4 and IL-10 which decreased till 7th, elevated toward 14th day although remained below control. Inflammation boosting was associated by oxidative stress activation during 1st week manifested by malonic dialdehyde (MAD) rise and total antioxidant activity fall. To be noted that markers improvement till 3rd month was poor and a conspicuous dynamics began since 6th month with nearing to control level toward 12th month. However, at this time following markers significantly differed from control value: TNF-alpha (+29,6%), IL-4 (-31,7%), S-nitrosothiols (-17,8%), CRPhs exceeded 3,0 g/L (4,77±0,38) and MAD (+23,6%). Conclusions: (1). Dynamics of inflammation markers in patients with STEMI during first 14 days after angioplasty conclusive reflect chronologic accumulation of inflammatory cells in necrotic zone. (2). Maximal serum plateau of MMP-8, IL-1, IL-6, IL-6, TNF-alpha and CRPhs goes till 7th day of post-infarct evolution, associated with lowest IL-4 and IL-10. (3). Marker improvements begin since 3rd month with nearing to control toward 12th month, excepting IL-4, TNF-alpha, CRPhs and MAD indicating thus a late statement of inflammation dissemination

    Конечные продукты гликирования и эластичность периферических артерий при сердечной недостаточности

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    Department of Interventional Cardiology, Institute of CardiologyAdvanced glycation and products (AGEs) are modifications of proteins or lipids that become nonenzymatically glycated and oxidized after contact with mono-sugars. Bounding to specific cell receptors they lead to cross-link formation basically of the large matrix proteins such as collagen and elastin resulting in increased stiffness of the vasculature. By this reason we evaluated the AGEs circulating levels and artery elasticity indices in heart failure due to diastolic or systolic dysfunction. In hypertensive patients with diastolic dysfunction AGEs level elevated 2.5 times while elasticity value of large and smooth arteries decreased by 54 and 46% respectively. Systolic dysfunction was associated with AGEs rising 2.9 times and smooths elasticity index diminution by almost 30%. Hence, the AGEs can be vied as a predictor of vascular stiffening and remedies of glycation inhibition may be useful in heart failure treatment.Конечные продукты гликирования (КПГ) представляют собой модифицированные белки или липиды, образующиеся при неферментативной гликации и способствующие формированию связей, в основном, белков интерстиция, коллагена и эластина, что приводит к увеличению ригидности сосудов. В этой связи мы определили уровень КПГ в крови и показатели эластичности периферических артерий при сердечной недостаточности. У гипертензивных больных с диастолической дисфункцией уровень КПГ был повышен в 3,5 раза, в то время как показатели эластичности больших и малых артерий снизились на 54 и 46% соответственно. Систолическая дисфункция сопровождалась увеличением КПГ в 2,9 раза и уменьшением эластичности малых артерий на 30%. КПГ могут быть рассмотрены как предиктор ригидности сосудов, а средства ингибирующие гликирование – как препараты для лечения сердечной недостаточности

    KrF pulsed laser deposition of chromium oxide thin films from Cr8O21 targets

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    Chromium oxides, CrxOy, are of great interest due to the wide variety of their technological applications. Among them, CrO2 has been extensively investigated in recent years because it is an attractive compound for use in spintronic heterostructures. However, its synthesis at low temperatures has been a difficult task due to the metastable nature of this oxide. This is indeed essential to ensure interface quality and the ability to coat thermal-sensitive materials such as those envisaged in spintronic devices. Pulsed Laser Deposition (PLD) is a technique that has the potential to meet the requirements stated above. In this work, we describe our efforts to grow chromium oxide thin films by PLD from Cr8O21 targets, using a KrF excimer laser. The as-deposited films were investigated by X-ray diffraction and Rutherford backscattering spectrometry. Structural and chemical composition studies showed that the films consist of a mixture of amorphous chromium oxides exhibiting different stoichiometries depending on the processing parameters, where nanocrystals of mainly Cr2O3 are dispersed. The analyses do not exclude the possibility of co-deposition of Cr2O3 and a low fraction of CrO2

    Field-induced criticality in a gapped quantum magnet with bond disorder

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    Neutron diffraction and calorimetric measurements are used to study the field-induced quantum phase transition in piperazinium-Cu2_2(Cl1x_{1-x}Brx_x)6_6 (x=0x=0, x=3.5% and x=7.5%), a prototypical quantum antiferromagnet with random bonds. The critical indexes ϕ\phi and β\beta are determined. The findings contradict some original predictions for Bose Glass based on the assumption z=dz=d, but are consistent with recent theoretical results implying z<dz<d. Inelastic neutron experiments reveal that disorder has a profound effect on the lowest-energy magnetic gap excitation in the system.Comment: 4.2 pages, 4 figures. Submitted to PRB Rapid Communication

    A first estimate of triply heavy baryon masses from the pNRQCD perturbative static potential

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    Within pNRQCD we compute the masses of spin-averaged triply heavy baryons using the now-available NNLO pNRQCD potentials and three-body variational approach. We focus in particular on the role of the purely three-body interaction in perturbation theory. This we find to be reasonably small and of the order 25 MeV Our prediction for the Omega_ccc baryon mass is 4900(250) in keeping with other approaches. We propose to search for this hitherto unobserved state at B factories by examining the end point of the recoil spectrum against triple charm.Comment: 18 figures, 21 page

    Gene expression patterns unveil a new level of molecular heterogeneity in colorectal cancer.

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    The recognition that colorectal cancer (CRC) is a heterogeneous disease in terms of clinical behaviour and response to therapy translates into an urgent need for robust molecular disease subclassifiers that can explain this heterogeneity beyond current parameters (MSI, KRAS, BRAF). Attempts to fill this gap are emerging. The Cancer Genome Atlas (TGCA) reported two main CRC groups, based on the incidence and spectrum of mutated genes, and another paper reported an EMT expression signature defined subgroup. We performed a prior free analysis of CRC heterogeneity on 1113 CRC gene expression profiles and confronted our findings to established molecular determinants and clinical, histopathological and survival data. Unsupervised clustering based on gene modules allowed us to distinguish at least five different gene expression CRC subtypes, which we call surface crypt-like, lower crypt-like, CIMP-H-like, mesenchymal and mixed. A gene set enrichment analysis combined with literature search of gene module members identified distinct biological motifs in different subtypes. The subtypes, which were not derived based on outcome, nonetheless showed differences in prognosis. Known gene copy number variations and mutations in key cancer-associated genes differed between subtypes, but the subtypes provided molecular information beyond that contained in these variables. Morphological features significantly differed between subtypes. The objective existence of the subtypes and their clinical and molecular characteristics were validated in an independent set of 720 CRC expression profiles. Our subtypes provide a novel perspective on the heterogeneity of CRC. The proposed subtypes should be further explored retrospectively on existing clinical trial datasets and, when sufficiently robust, be prospectively assessed for clinical relevance in terms of prognosis and treatment response predictive capacity. Original microarray data were uploaded to the ArrayExpress database (http://www.ebi.ac.uk/arrayexpress/) under Accession Nos E-MTAB-990 and E-MTAB-1026. © 2013 Swiss Institute of Bioinformatics. Journal of Pathology published by John Wiley &amp; Sons Ltd on behalf of Pathological Society of Great Britain and Ireland
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