Riemann–Hilbert problems, Toeplitz operators and Q-classes

We generalize the notion of Q-classes C(Q1,Q2) , which was introduced in the context of Wiener–Hopf factorization, by considering very general 2 × 2 matrix functions Q1, Q2. This allows us to use a mainly algebraic approach to obtain several equivalent representations for each class, to study the intersections of Q-classes and to explore their close connection with certain non-linear scalar equations. The results are applied to various factorization problems and to the study of Toeplitz operators with symbol in a Q-class. We conclude with a group theoretic interpretation of some of the main results.Fundação para a Ciência e a Tecnologia (FCT/Portugal), through Project PTDC/MAT/121837/2010 and Project Est- C/MAT/UI0013/2011. The first author was also supported by the Center for Mathematical Analysis, Geometry, and Dynamical Systems and the second author was also supported by the Centre of Mathematics of the University of Minho through the FEDER Funds Programa Operacional Factores de Competitividade COMPET

MODELING OF THE KINETIC OF SALICYLIC ACID ADSORPTION IN POLYMERIC AND ACTIVATED CHARCOAL ADSORBENTS

The understanding of adsorption mechanisms of compounds utilized in many medications and prescription drugs represents an important step for the development of different separation processes of such substances. The adsorption kinetic study of such chemical compounds through the application of new models permits a better comprehension of the involved mechanisms, leading to the estimation of important parameters that will be incorporated in the equipment design. In this work a kinetic model of irreversible adsorption is implemented, which is dependent on both solute and site concentrations. It showed to be very effective correlating the simulated results with the adsorption experiments of salicylic acid through three adsorbents in different temperature conditions. The application of an inverse problem approach, with the minimization of the squared residues cost function, was successful in determining the kinetic parameters. The increase in the kinetic constants obtained with the temperature increase was followed by a reduction in the adsorption capacity of the adsorbents. Thermodynamic parameters were also estimated, leading to the comprehension about the equilibrium states of the adsorption systems considered

What Physical Education Teachers Know About Asthma: Impact of a Training Course

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Distribution of polymorphisms IL4 -590 C/T and IL4 RP2 in the human populations of Madeira, Azores, Portugal, Cape

Abstract: The IL4 gene is located on chromosome 5q23.3-31.2. Polymorphisms within this cytokine gene, like the derivative allele T of IL4-590, have been reported as being associated to elevated IgE serum levels and asthma. In the present work, the allelic and genotypic frequency of the IL4-590 and IL4 RP2 polymorphisms was carried out in 599 individuals from Madeira, Azores, Portugal mainland, Cape Verde and Guinea-Bissau and in a sample of 101 asthmatics from Madeira population. In all populations the polymorphisms were in LD and presented a significant dissimilar allelic and genotypic distribution (p<0.05) except between mainland Portugal and Madeira when compared to Azores. Significant differences regarding both loci were found between Madeira population and the group of asthmatics. Genotype 183183TT frequency is higher for African populations while 253253CC prevails in Caucasian populations. The existence of a Hardy-Weinberg Disequilibrium in Guinea-Bissau population not observed in neutral markers leads to the hypothesis of natural selection occurring in these loci probably associated to a rapid population growth an hypothesis strengthened by neutral STRs D5S818 and CSF1PO gene diversity.info:eu-repo/semantics/publishedVersio

Avaliação das Vasculopatias Não Ateroscleróticas por Ecografia-Doppler

The non-atherosclerotic vasculopathies are an uncommon group of disorders, with diverse etiopathogenesis, involving younger patients when compared with atherosclerotic disease. Clinical presentation varies from acute vascular events - ischemic or hemorrhagic- to uncharacteristic neurologic syndromes. Although the cerebral angiography is the gold standard diagnostic method due to its high sensibility, its specificity is low mainly when compared to imaging evaluation of the arterial wall with carotid and vertebral ultrasound-doppler. We reinforce the importance of this non-invasive and radiation-free exam, not only in the diagnosis but also in the monitoring of these patients - young patients who need a regular and extended evaluationinfo:eu-repo/semantics/publishedVersio

Iohexol Clearance for Determination of Glomerular Filtration Rate in Rats Induced to Acute Renal Failure

IntroductionThe glomerular filtration rate (GFR) is considered an especially important tool for the measurement of renal function. Inulin clearance (InCl) is the classic reference method for this purpose, although it is associated with a number of disadvantages; thus, other markers have been proposed, including iohexol. Determination of iohexol clearance (IoCl) has been established for clinical use; however, its application as a GFR marker in experimental rat models has not been reported.ObjectivesThis study aims to standardize a methodology for the measurement of iohexol clearance and to evaluate its applicability as a marker of GFR in rats with induced toxic acute renal failure (ARF), using InCl as the gold standard.Materials and MethodsTwenty-six Wistar male rats (200-300 g) were divided into the following two groups: a control group (n=7) and an ARF group (n=19). ARF was induced by the subcutaneous administration of cisplatin (5 mg/kg); IoCl and InCl were determined simultaneously, and plasma creatinine (pCreat) dosage was measured colorimetrically.ResultsThe pCreat, InCl and IoCl levels were consistent with the expected values for the renal function ranges of the evaluated animals, and the IoCl and InCl levels were significantly correlated (r=0.792). An inverse moderate linear correlation between the IoCl and pCreat measurements (r=-0.587) and between the InCl and pCreat measurements (r=-0.722) were observed.ConclusionThese results confirm a correlation between IoCl and the gold standard of GFR, InCl measurement. IoCl offers a relevant advantage over InCl because determination of the former allows the animal to live after the procedure.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo, Dept Med, Div Nephrol, São Paulo, SP, BrazilUniv São Paulo, Inst Biomed Sci, Dept Immunol, São Paulo, SP, BrazilUniv São Paulo, Sch Med, Dept Nephrol, São Paulo, SP, BrazilUniversidade Federal de São Paulo, Dept Med, Div Nephrol, São Paulo, SP, BrazilWeb of Scienc

Beyond SDI: Integrating Science and Communities to Create Environmental Policies for the Sustainability of the Amazon

This paper will explore ways to go beyond the traditional SDI (spatial data infrastructures) in the direction of the Digital Earth, with the objective of supporting environmental policies that will lead to sustainability. We use the Amazon region as a starting point for the discussion. Environmental policy making for a place such as the Amazon has to take into account that phenomena occur and are modeled in various geographic scales, ranging from microbiology to planetary climate impacts. There are also multiple and sometimes conflicting views on the same reality, including the many scientific disciplines, governmental and non-governmental views, and the view of the local populations. Currently, the combination of technologies, people, and policies that defines an SDI is probably the best approximation we have to solve these problems, but some important elements are missing. A broader SDI would be an enabler for understanding space, not only delivering general-purpose maps, but disseminating spatial data to support policies for sustainable development. We think it is necessary to go beyond SDI to integrate science and communities in the effort of creating, enforcing, assessing, and revising environmental policies. We discuss the limitations of current SDIs with regards to data and information flow, semantics, and community building. We also review the information needs and modeling challenges for SDIs when used as a support for environmental policy making

Palynological study of the endemic woody sonchus fron the flora of Madeira: a morphological and molecular approach

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The palace of the Marquises of Alegrete in Mouraria: the absent palace and the place memory

Built by Manuel Teles da Silva (1641-1709), 2nd count of Vilar Maior and 1st Marquis of Alegrete, and named after his title, this sumptuous palace built near the Ferdinand Wall, stood out as an important Noble House in the context of the civil architecture of Lisbon, in the early 18th century. After a long and troubled life, due to the modifications caused by successive social and urban adaptations it would become finally demolished in 1946. In this article we propose to study this building, based on several collections, mainly in the municipal archives, in two specific moments: its foundation and initial construction, and the years that corresponded to its degradation and demolition, as well as those who dwelt in addition to its relationship with the surrounding urban area.info:eu-repo/semantics/publishedVersio

Geo-environmental mapping using physiographic analysis: constraints on the evaluation of land instability and groundwater pollution hazards in the Metropolitan District of Campinas, Brazil

Geo-environmental terrain assessments and territorial zoning are useful tools for the formulation and implementation of environmental management instruments (including policy-making, planning, and enforcement of statutory regulations). They usually involve a set of procedures and techniques for delimitation, characterisation and classification of terrain units. However, terrain assessments and zoning exercises are often costly and time-consuming, particularly when encompassing large areas, which in many cases prevent local agencies in developing countries from properly benefiting from such assessments. In the present paper, a low-cost technique based on the analysis of texture of satellite imagery was used for delimitation of terrain units. The delimited units were further analysed in two test areas situated in Southeast Brazil to provide estimates of land instability and the vulnerability of groundwater to pollution hazards. The implementation incorporated procedures for inferring the influences and potential implications of tectonic fractures and other discontinuities on ground behaviour and local groundwater flow. Terrain attributes such as degree of fracturing, bedrock lithology and weathered materials were explored as indicators of ground properties. The paper also discusses constraints on- and limitations of- the approaches taken