Thin waveguides with Robin boundary conditions

We consider the Laplace operator in a thin three dimensional tube with a Robin type condition on its boundary and study, asymptotically, the spectrum of such operator as the diameter of the tube's cross section becomes infinitesimal. In contrast with the Dirichlet condition case, we evidence different behaviors depending on a symmetry criterium for the fundamental mode in the cross section. If that symmetry condition fails, then we prove the localization of lower energy levels in the vicinity of the minimum point of a suitable function on the tube's axis depending on the curvature and the rotation angle. In the symmetric case, the behavior of lower energy modes is shown to be ruled by a one dimensional Sturm-Liouville problem involving an effective potential given in explicit form

Arsenic in rice agrosystems (water, soil and rice plants) in Guayas and Los Rios provinces, Ecuador

Geogenic arsenic (As) can accumulate and reach high concentrations in rice grains, thus representing a potential threat to human health. Ecuador is one of the main consumers of rice in South America. However, there is no information available about the concentrations of As in rice agrosystems, although some water bodies are known to contain high levels of the element. We carried out extensive sampling of water, soil, rice plants and commercial rice (obtained from local markets). Water samples were analysed to determine physico-chemical properties and concentrations of dissolved arsenic. Soil samples were analysed to determine total organic C, texture, total Fe and amorphous Fe oxyhydroxides (Fe-ox), total arsenic (tAs) and the bioavailable fraction (As-Me). The different plant parts were analysed separately to determine total (tAs), inorganic (iAs) and organic arsenic (oAs). Low concentrations of arsenic were found in samples of water (generally 80%) in all parts of the rice plants. (C) 2016 Elsevier B.V. All rights reserved

Hydrodynamic scaling from the dynamics of relativistic quantum field theory

Hydrodynamic behavior is a general feature of interacting systems with many degrees of freedom constrained by conservation laws. To date hydrodynamic scaling in relativistic quantum systems has been observed in many high energy settings, from cosmic ray detections to accelerators, with large particle multiplicity final states. Here we show first evidence for the emergence of hydrodynamic scaling in the dynamics of a relativistic quantum field theory. We consider a simple scalar $\lambda \phi^4$ model in 1+1 dimensions in the Hartree approximation and study the dynamics of two colliding kinks at relativistic speeds as well as the decay of a localized high energy density region. The evolution of the energy-momentum tensor determines the dynamical local equation of state and allows the measurement of the speed of sound. Hydrodynamic scaling emerges at high local energy densities.Comment: 4 pages, 4 color eps figures, uses RevTex, v2 some typos corrected and references adde

Fracture of the posterior malleolus: an underdiagnosed condition

The ankle joint is the most commonly injured joint during sports activity. While ankle sprains occur more frequently, ankle fractures are less common. Due to its low incidence, the isolated fracture of the posterior malleolus still represents a diagnosis challenge. This article reports a case of a female with a posterior malleolus isolated fracture after falling while performing sports activity. Clinical examination and conventional radiography were consistent with diagnosis of a simple ankle sprain and the patient was discharged with a conservative approach for lateral ankle sprain. Due to persistent pain the patient return for additional examination, which the differential diagnosis revealed an isolated fracture of the posterior malleolus without displacement of the fragment. The patient was immobilized with a suropodalic splint for 4 weeks followed by additional conservative. At the fourth month of follow-up, the patient was asymptomatic and showed good clinical and functional outcomes. This case highlights the importance of a comprehensive medical history and detailed clinical examination which may reveal pathological features that require a differential diagnosis

POLQUAL : measuring service quality in police traffic services

Purpose The purpose of this paper is to build a customer quality assessment scale for use in the field of policing – POLQUAL. It adapts and applies a modified SERVQUAL approach to police traffic services in Portugal. Design/methodology/approach Original data was collected by means of telephone interviews over a three‐month period. The proposed scale's reliability and validity are assessed. Findings The study shows how it is possible to implement a SERVQUAL‐based approach in police traffic services. The adapted scale – POLQUAL – includes all five original dimensions plus another new dimension “promptitude”. The most negative gaps found are for the dimensions of reliability and tangibles. There was evidence that perceived quality of service decreases as the level of education of the driver increases. The paper did not find a difference between perceived quality of service provided between requested services and imposed services, respectively, represented by the accident service and radar service. Research limitations/implications The results are based on a specific police services context – that of out of office traffic services in Portugal. Practical implications The study provides the police traffic services with a tool for measuring quality of service which can provide information for focusing improvement efforts. Social implications Often the user cannot choose to interact with police services. However, in a democratic society good quality of service is essential for maintaining trust in the police services. Originality/value The study provides police traffic services with a valid and reliable tool to assess quality of service from the user's perspective.info:eu-repo/semantics/publishedVersio

Novel mutation in addition to functional TMPRSS6 gene polymorphisms originate an IRIDA-like phenotype in an African child

Iron-refractory iron deficiency anemia (IRIDA) is a rare autosomal recessive anemia often unresponsive to oral iron intake and partially responsive to parenteral iron treatment. The disease originates from mutations in TMPRSS6 gene, encoding Matriptase 2, a transmembrane serine protease that plays an essential role in down-regulating hepcidin. Once TMPRSS6 is mutated, the corresponding protein is absent or inactive at the hepatocyte membrane leading to uncontrolled high levels of hepcidin and impaired iron absorption. This study aimed to investigate a 4-year-old boy of sub-Saharan ancestry (Mozambique/Angola), presenting with microcytic hypochromic anemia, low transferrin saturation, normal ferritin, and having a partial response to intravenous iron treatment. He is a -α3.7-thalassemia carrier. TMPRSS6 was screened for variants by Next-Generation Sequencing using Nextera XT libraries in a MiSeq platform (Illumina). Genetic variants found were validated by Sanger sequencing. In silico analyses were performed in HSF, SIFT, Poly-Phen2 and Missense3D softwares. A novel missense mutation (c.871G>A) was found in heterozygosity, in TMPRSS6 exon 8. In silico analysis indicates the conserved amino acid change (G291S) may be damaging to the protein stability. Due to its location in the CUB1 domain, it may also affect the enzyme activation and substrate recognition. Additionally, 3 SNPs previously associated with a greater risk of developing iron deficiency anemia (K253E, V736A and Y739Y) were also identified in TMPRSS6. Although IRIDA is known as an autosomal recessive disease, we conclude that, in this case, the result of a digenic inheritance of the novel damaging mutation (c.871G>A; G291S) and the 3 common modulating SNPs in the same gene and a co-inheritance of the α-thalassemia HBA deletion may lead to an IRIDA-like phenotype. Further functional studies of the mutated protein as well as family studies should be conducted.This work was partially supported by INSA_2013DGH910 and GenomePT (POCI-01-0145-FEDER-022184).info:eu-repo/semantics/publishedVersio

A simple business-cycle model with schumpeterian features

We develop a dynamic general equilibrium model of imperfect competition where a sunk cost of creating a new product regulates the type of entry that dominates in the economy: new products or more competition in existing industries. Considering the process of product innovation is irreversible, introduces hysteresis in the business cycle. Expansionary shocks may lead the economy to a new 'prosperity plateau,' but contractionary shocks only affect the market power of mature industries

Manufacturing and Management Paradigms, Methods and Tools for Sustainable Industry 4.0-Oriented Manufacturing Systems

In the current Industry 4.0 era (I4.0, for short) [1–3], manufacturing and management (M&M) paradigms, methods and tools should be wisely developed to fulfil sustainability issues, regarding not just economic but also social and environmental concerns by simultaneously fostering organizational efficiency excellence and transformational initiatives, therefore contributing to enduring business results.This Special Issue aims to provide new insights regarding manufacturing or management paradigms (strategies), methods, tools, and practices aligned with the contemporary necessity to create and implement sustainable I4.0 manufacturing systems. Each of the five selected papers of this Special Issue makes a novel contribution to that aim.This work was supported by national funds through the FCT—Fundação para a Ciência e Tecnologia through the R&D Units Project Scopes: UIDB/00319/2020, UIDB/50014/2020, and EXPL/EME-SIS/1224/2021.info:eu-repo/semantics/publishedVersio