Parametrization of spectral surfaces of a class of periodic 5-diagonal matrices

The main result of this work is a parametric description of the spectral surfaces of a class of periodic 5-diagonal matrices, related to the strong moment problem. This class is a self-adjoint twin of the class of CMV matrices. Jointly they form the simplest possible classes of 5-diagonal matrices.

Characterisation of the LMS200 laser beam under the influence of blockage surfaces. Influence on 3D scanning of tree orchards

The geometric characterisation of tree orchards is a high-precision activity comprising the accurate measurement and knowledge of the geometry and structure of the trees. Different types of sensors can be used to perform this characterisation. In this work a terrestrial LIDAR sensor (SICK LMS200) whose emission source was a 905-nm pulsed laser diode was used. Given the known dimensions of the laser beam cross-section (with diameters ranging from 12 mm at the point of emission to 47.2 mm at a distance of 8 m), and the known dimensions of the elements that make up the crops under study (flowers, leaves, fruits, branches, trunks), it was anticipated that, for much of the time, the laser beam would only partially hit a foreground target/object, with the consequent problem of mixed pixels or edge effects. Understanding what happens in such situations was the principal objective of this work. With this in mind, a series of tests were set up to determine the geometry of the emitted beam and to determine the response of the sensor to different beam blockage scenarios. The main conclusions that were drawn from the results obtained were: (i) in a partial beam blockage scenario, the distance value given by the sensor depends more on the blocked radiant power than on the blocked surface area; (ii) there is an area that influences the measurements obtained that is dependent on the percentage of blockage and which ranges from 1.5 to 2.5 m with respect to the foreground target/object. If the laser beam impacts on a second target/object located within this range, this will affect the measurement given by the sensor. To interpret the information obtained from the point clouds provided by the LIDAR sensors, such as the volume occupied and the enclosing area, it is necessary to know the resolution and the process for obtaining this mesh of points and also to be aware of the problem associated with mixed pixels.

Implementation of a robust coded structured light technique for dynamic 3D measurements

This paper presents the implementation details of a coded structured light system for rapid shape acquisition of unknown surfaces. Such techniques are based on the projection of patterns onto a measuring surface and grabbing images of every projection with a camera. Analyzing the pattern deformations that appear in the images, 3D information of the surface can be calculated. The implemented technique projects a unique pattern so that it can be used to measure moving surfaces. The structure of the pattern is a grid where the color of the slits are selected using a De Bruijn sequence. Moreover, since both axis of the pattern are coded, the cross points of the grid have two codewords (which permits to reconstruct them very precisely), while pixels belonging to horizontal and vertical slits have also a codeword. Different sets of colors are used for horizontal and vertical slits, so the resulting pattern is invariant to rotation. Therefore, the alignment constraint between camera and projector considered by a lot of authors is not necessary

What is the Jacobian of a Riemann surface with boundary?

We define the Jacobian of a Riemann surface with analytically parametrized boundary components. These Jacobians belong to a moduli space of "open abelian varieties" which satisfies gluing axioms similar to those of Riemann surfaces, and therefore allows a notion of "conformal field theory" to be defined on this space. We further prove that chiral conformal field theories corresponding to even lattices factor through this moduli space of open abelian varieties.

Development of an optimized methodology for tensile testing of carbon steels in hydrogen environment

The study was performed at OCAS, the Steel Research Centre of ArcelorMittal for the Industry market. The major aim of this research was to obtain an optimized tensile testing methodology with in-situ H-charging to reveal the hydrogen embrittlement in various high strength steels. The second aim of this study has been the mechanical characterization of the hydrogen effect on hight strength carbon steels with varying microstructure, i.e. ferrite-martensite and ferrite-bainite grades. The optimal parameters for H-charging - which influence the tensile test results (sample geometry type of electrolyte, charging methods effect of steel type, etc.) - were defined and applied to Slow Strain Rate testing, Incremental Step Loading and Constant Load Testing. To better understand the initiation and propagation of cracks during tensile testing with in-situ H-charging, and to make the correlation with crystallographic orientation, some materials have been analyzed in the SEM in combination with the EBSD technique. The introduction of a notch on the tensile samples permits to reach a significantly improved reproducibility of the results. Comparing the various steel grades reveals that Dual Phase (ferrite-martensite) steels are more sensitive to hydrogen induced cracking than the FB (ferritic-bainitic) ones. This higher sensitivity to hydrogen was found back in the reduced failure times, increased creep rates and enhanced crack initiation (SEM) for the Dual Phase steels in comparison with the FB steels.

Protocol of the COSMIN study: consensus-based standards for the selection of health measurement instruments

Background: Choosing an adequate measurement instrument depends on the proposed use of the instrument, the concept to be measured, the measurement properties (e.g. internal consistency, reproducibility, content and construct validity, responsiveness, and interpretability), the requirements, the burden for subjects, and costs of the available instruments. As far as measurement properties are concerned, there are no sufficiently specific standards for the evaluation of measurement properties of instruments to measure health status, and also no explicit criteria for what constitutes good measurement properties. In this paper we describe the protocol for the COSMIN study, the objective of which is to develop a checklist that contains COnsensus-based Standards for the selection of health Measurement INstruments, including explicit criteria for satisfying these standards. We will focus on evaluative health related patient-reported outcomes (HR-PROs), i.e. patient-reported health measurement instruments used in a longitudinal design as an outcome measure, excluding health care related PROs, such as satisfaction with care or adherence. The COSMIN standards will be made available in the form of an easily applicable checklist.Method: An international Delphi study will be performed to reach consensus on which and how measurement properties should be assessed, and on criteria for good measurement properties. Two sources of input will be used for the Delphi study: (1) a systematic review of properties, standards and criteria of measurement properties found in systematic reviews of measurement instruments, and (2) an additional literature search of methodological articles presenting a comprehensive checklist of standards and criteria. The Delphi study will consist of four (written) Delphi rounds, with approximately 30 expert panel members with different backgrounds in clinical medicine, biostatistics, psychology, and epidemiology. The final checklist will subsequently be field-tested by assessing the inter-rater reproducibility of the checklist.Discussion: Since the study will mainly be anonymous, problems that are commonly encountered in face-to-face group meetings, such as the dominance of certain persons in the communication process, will be avoided. By performing a Delphi study and involving many experts, the likelihood that the checklist will have sufficient credibility to be accepted and implemented will increase.

Synovial fluid examination for the diagnosis of synovial amyloidosis in patients with chronic renal failure undergoing haemodialysis

The diagnosis of synovial amyloidosis is based upon synovial biopsy. Synovial fluid (SF) in seven patients with amyloid arthropathy associated with chronic renal failure undergoing haemodialysis were studied. The SF and synovial samples of 10 consecutive patients with seronegative mono- or oligoarthritis served as controls. Six of the seven patients with amyloid positive synovial biopsy specimens showed amyloid in their SF. No amyloid was found in the synovial tissue or fluid of the 10 patients in the control group, the sensitivity being 87.7%. The finding of amyloid in SF was highly reproducible, showing its presence in the same joint on several occasions. The deposits were Congophilia resistant to potassium permanganate pretreatment, and the immunohistochemical analysis proved that they contained beta 2 microglobulin. The high sensitivity and good reproducibility of the method shows that the finding of amyloid in SF is sufficient for the diagnosis of synovial amyloidosis. It is possible to perform immunohis

Structural characterization of laser-treated Cr3C2-NiCr coatings

The interconnected porosity of the Cr3C2-NiCr coatings obtained by high-velocity oxy fuel spraying is detrimental in corrosion and wear resistance applications. Laser treatments allow sealing of their surfaces through melting and resolidification of a thin superficial layer. A Nd:YAG laser beam was used to irradiate Cr3C2-NiCr coatings either in the continuous wave mode or at different repetition rates in the pulsed one. Results indicated that high peak and low mean laser irradiances are not good, since samples presented deep grooves and an extensive crack network. At low peak and higher mean laser irradiances the surface was molten, and only a few shallow cracks were observed. The interconnected porosity was completely eliminated in a layer up to 80 m thick, formed by large Cr7C3 grains imbedded in a NiCr matrix.

Structural characterization of laser-treated Cr3C2-NiCr coatings

The interconnected porosity of the Cr3C2-NiCr coatings obtained by high-velocity oxy fuel spraying is detrimental in corrosion and wear resistance applications. Laser treatments allow sealing of their surfaces through melting and resolidification of a thin superficial layer. A Nd:YAG laser beam was used to irradiate Cr3C2-NiCr coatings either in the continuous wave mode or at different repetition rates in the pulsed one. Results indicated that high peak and low mean laser irradiances are not good, since samples presented deep grooves and an extensive crack network. At low peak and higher mean laser irradiances the surface was molten, and only a few shallow cracks were observed. The interconnected porosity was completely eliminated in a layer up to 80 m thick, formed by large Cr7C3 grains imbedded in a NiCr matrix.

Periodic points of holomorphic maps via Lefschetz numbers

In this paper we study the set of periods of holomorphic maps on compact manifolds, using the periodic Lefschetz numbers introduced by Dold and Llibre, which can be computed from the homology class of the map. We show that these numbers contain information about the existence of periodic points of a given period; and, if we assume the map to be transversal, then they give us the exact number of such periodic orbits. We apply this result to the complex projective space of dimension n and to some special type of Hopf surfaces, partially characterizing their set of periods. In the first case we also show that any holomorphic map of CP(n) of degree greater than one has infinitely many distinct periodic orbits, hence generalizing a theorem of Fornaess and Sibony. We then characterize the set of periods of a holomorphic map on the Riemann sphere, hence giving an alternative proof of Baker's theorem.

Synovial fluid examination for the diagnosis of synovial amyloidosis in patients with chronic renal failure undergoing haemodialysis

The diagnosis of synovial amyloidosis is based upon synovial biopsy. Synovial fluid (SF) in seven patients with amyloid arthropathy associated with chronic renal failure undergoing haemodialysis were studied. The SF and synovial samples of 10 consecutive patients with seronegative mono- or oligoarthritis served as controls. Six of the seven patients with amyloid positive synovial biopsy specimens showed amyloid in their SF. No amyloid was found in the synovial tissue or fluid of the 10 patients in the control group, the sensitivity being 87.7%. The finding of amyloid in SF was highly reproducible, showing its presence in the same joint on several occasions. The deposits were Congophilia resistant to potassium permanganate pretreatment, and the immunohistochemical analysis proved that they contained beta 2 microglobulin. The high sensitivity and good reproducibility of the method shows that the finding of amyloid in SF is sufficient for the diagnosis of synovial amyloidosis. It is possible to perform immunohis

Estimating the Ontogenetic Status of an Enantiornithine Bird from the Lower Barremian of El Montsec, Central Pyrenees, Spain.

An Enantiornithes specimen from El Montsec was initially described as an immature individual based upon qualitative traits such as its relatively large orbit and overall proportions of the skull and the postcranium. In this study we re-evaluate the precise determination of the ontogenetic stage of this individual, establishing a cross-talk among taphonomic, anatomic, and morphometric data. The exceptional preservation of the specimen has allowed pondering ontogenetic influence versus preservational bias in features like the external patterns of bone surfaces, instead of being aprioristically considered due to taphonomic alterations only. The rough texture of the periosteal bone associated with pores in the distal, proximal and mid-shaft areas of the humeral shaft, indicates a subadult stage when compared with long bones of modern birds. Forelimb proportions of embryo and juvenile Enanthiornithes are equivalent to those of adult individuals of other taxa within this clade, though this is not a reliable criterion for establishing a precise ontogenetic stage. The El Montsec specimen may be attributed a close adulthood, yet only if growth regimes in Enantiornithes are considered equivalent to those in Neornithes birds.

Different Storing and Processing Conditions of Human Lymphocytes do not Alter P-Glycoprotein Rhodamine 123 Efflux.

P-glycoprotein (Pgp), a protein codified by Multi Drug Resistance (MDR1) gene, has a detoxifying function and might influence the toxicity and pharmacokinetics and pharmacodynamics of drugs. Sampling strategies to improve Pgp studies could be useful to optimize the sensitivity and the reproducibility of efflux assays. This study aimed to compare Pgp expression and efflux activity by measuring Rhodamine123 (Rh123) retention in lymphocytes stored under different conditions, in order to evaluate the potential utility of any of the storing conditions in Pgp functionality. Our results show no change in protein expression of Pgp by confocal studies and Western blotting, nor changes at the mRNA level (qRT-PCR). No differences in Rh123 efflux by Pgp activity assays were found between fresh and frozen lymphocytes after 24 hours of blood extraction, using either of the two Pgp specific inhibitors (VP and PSC833). Different working conditions in the 24 hours post blood extraction do not affect Rh123 efflux. These results allow standardization of Pgp activity measurement in different individuals with different timing of blood sampling and in different geographic areas. _______________

Spottier Targets Are Less Attractive to Tabanid Flies: On the Tabanid-Repellency of Spotty Fur Patterns

During blood-sucking, female members of the family Tabanidae transmit pathogens of serious diseases and annoy their host animals so strongly that they cannot graze, thus the health of the hosts is drastically reduced. Consequently, a tabanid-resistant coat with appropriate brightness, colour and pattern is advantageous for the host. Spotty coats are widespread among mammals, especially in cattle (Bos primigenius). In field experiments we studied the influence of the size and number of spots on the attractiveness of test surfaces to tabanids that are attracted to linearly polarized light. We measured the reflection-polarization characteristics of living cattle, spotty cattle coats and the used test surfaces. We show here that the smaller and the more numerous the spots, the less attractive the target (host) is to tabanids. We demonstrate that the attractiveness of spotty patterns to tabanids is also reduced if the target exhibits spottiness only in the angle of polarization pattern, while being homogeneous grey with a constant high degree of polarization. Tabanid flies respond strongly to linearly polarized light, and we show that bright and dark parts of cattle coats reflect light with different degrees and angles of polarization that in combination with dark spots on a bright coat surface disrupt the attractiveness to tabanids. This could be one of the possible evolutionary benefits that explains why spotty coat patterns are so widespread in mammals, especially in ungulates, many species of which are tabanid hosts