An investigation into the effects of resonances on the time delay estimate for leak detection in buried plastic water distribution pipes

In water distribution systems, old metallic pipes have been replaced by plastic pipes due to their deterioration over time. Although acoustic methods are effective in finding leaks in metallic pipes, they have been found to be problematic when applied to plastic pipes due to the high damping within the pipe wall and the surrounding medium. This is responsible for the leak signal not traveling long distances. Moreover, the leak energy in plastic pipes is generally located at a narrow frequency range located at low frequencies. However, the presence of resonances can narrow even more this frequency range. In order to minimise the influence of background noise and resonances on the calculation of the time delay estimate, band-pass filters are often used to supress undesirable frequency components of the noise. The objective of this paper is to investigate the influence of resonances in the pipe system (pipe, valves, connections and hydrants), on the time delay estimate calculated using acoustic signals. Analytical models and actual leak data collected in a bespoke rig located in the United Kingdom are used to investigate this feature.

Characterization of the nonlinear behavior of a F-16 aircraft using discrete-time Volterra series

The linearity assumption in the structural dynamics analysis is a severe practical limitation. Further, in the investigation of mechanisms presented in fighter aircrafts, as for instance aeroelastic nonlinearity, friction or gaps in wing-load-payload mounting interfaces, is mandatory to use a nonlinear analysis technique. Among different approaches that can be used to this matter, the Volterra theory is an interesting strategy, since it is a generalization of the linear convolution. It represents the response of a nonlinear system as a sum of linear and nonlinear components. Thus, this paper aims to use the discrete-time version of Volterra series expanded with Kautz filters to characterize the nonlinear dynamics of a F-16 aircraft. To illustrate the approach, it is identified and characterized a non-parametric model using the data obtained during a ground vibration test performed in a F-16 wing-to-payload mounting interfaces. Several amplitude inputs applied in two shakers are used to show softening nonlinearities presented in the acceleration data. The results obtained in the analysis have shown the capability of the Volterra series to give some insight about the nonlinear dynamics of the F-16 mounting interfaces. The biggest advantage of this approach is to separate the linear and nonlinear contributions through the multiple convolutions through the Volterra kernels.

Forensic electrochemistry: indirect electrochemical sensing of the components of the new psychoactive substance Synthacaine

Synthacaine is a New Psychoactive Substance which is, due to its inherent psychoactive properties, reported to imitate the effects of cocaine and is therefore consequently branded as legal cocaine. The only analytical approach reported to date for the sensing of Synthacaine is mass spectrometry. In this paper, we explore and evaluate a range of potential analytical techniques for its quantification and potential use in the field screening Synthacaine using Raman spectroscopy, presumptive (colour) testing, High Performance Liquid Chromatography (HPLC) and electrochemistry. HPLC analysis of street samples reveals that Synthacaine comprises a mixture of methiopropamine (MPA) and 2-aminoindane (2-AI). Raman spectroscopy and presumptive (colour) tests, the Marquis, Mandelin, Simon's and Robadope test, are evaluated towards a potential in-the-field screening approach but are found to not be able to discriminate between the two when they are both present in the same sample, as is the case in the real street samples. We report for the first time a novel indirect electrochemical protocol for the sensing of MPA and 2-AI which is independently validated in street samples with HPLC. This novel electrochemical approach based upon one-shot disposable cost effective screen-printed graphite macroelectrodes holds potential for in-the-field screening for Synthacaine.

ANALYSIS OF THE NATURAL VIBRATION FREQUENCY TEST METHOD TO OBTAIN THE MODULUS OF ELASTICITY OF WOOD STRUCTURAL COMPONENTS

There are several techniques to characterize the elastic modulus of wood and those currently using the natural frequencies of vibration stand out as they are non-destructive techniques, producing results that can be repeated and compared over time. This study reports on the effectiveness of the testing methods based on the natural frequencies of vibration versus static bending to obtain the elastic properties of reforested structural wood components usually employed in civil construction. The following components were evaluated: 24 beams of Eucalyptus sp. with nominal dimensions (40 x 60 x 2.000 mm) and 14 beams of Pinus oocarpa with nominal dimensions (45 x 90 x 2.300 mm) both without treatment; 30 boards with nominal dimensions (40 x 240 x 2.010 mm) and 30 boards with nominal dimensions (40 x 240 x 3.050 mm), both of Pinus oocarpa and with chromate copper arsenate (CCA) preservative treatment. The results obtained in thiswork show good correlation when compared to the results obtained by the static bending mechanical method, especially when applying the natural frequency of longitudinal vibration. The use of longitudinal frequency was reliable and practical, therefore recommended for determining the modulus of elasticity of wood structural elements. It was also found that no specific support is needed for the specimens using the longitudinal frequency, as well as no previous calibrations, reducing the execution time and enabling to test many samples.

Divide to conquer: a complex pattern of biodiversity depicted by vertebrate components in the Brazilian Atlantic Forest

The identification of northern and southern components in different vertebrate species led researchers to accept a two-component hypothesis for the Brazilian Atlantic forest (BAF). Nevertheless, neither a formal proposal nor a meta-analysis to confirm this coincidence was ever made. Our main objective here was therefore to systematically test in how many vertebrate components the BAF could be divided by analysing existing empirical data. We used two approaches: (1) mapping and comparing the proposed areas of vertebrate endemism in the BAF and (2) analysing studies mentioning spatial subdivisions in distinct forest-dependent vertebrates within the biome, by the use of panbiogeography. The four large-scale endemism area components together with the six small-scale panbiogeographical ones allowed the definition of three BAF greater regions, subdivided into nine vertebrate components, latitudinally and longitudinally organized. Empirical time estimates of the diversification events within the BAF were also reviewed. Diversification of these vertebrates occurred not only in the Pleistocene but also throughout the Miocene. Our results confirm the BAF's complex history, both in space and time. We propose that future research should be small-scale and focused in the vertebrate components identified herein. Given the BAF's heterogeneity, studying via sections will be much more useful in identifying the BAF's historical biogeography. (c) 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 107, 39-55.

Evolution of time-control mechanisms in subterranean organisms: cave fishes under light-dark cycles (Teleostei: Siluriformes, Characiformes)

Subterranean organisms are excellent models for chronobiological studies, yet relatively few taxa have been investigated with this focus. Former results were interpreted as a pattern of regression of circadian locomotor activity rhythms in troglobitic (exclusively subterranean) species. In this paper we report results of experiments with cave fishes showing variable degrees of troglomorphism (reduction of eyes, melanic pigmentation and other specializations related to the hypogean life) submitted to light-dark cycles, preceded and followed by several days in constant darkness. Samples from seven species have been monitored in our laboratory for the detection of significant circadian rhythms in locomotor activity: S. typhlops, an extremely troglomophic species, presented the lowest number of significant components in the circadian range (only one individual out of eight in DD1 and three other fish in LD), all weak (low values of spectral power). Higher incidence of circadian components was observed for P. kronei - only one among six studied catfish without significant circadian rhythms under DD1 and DD2; spectral powers were generally high. Intermediate situations were observed for the remaining species, however all of them presented relatively strong significant rhythms under LD. Residual oscillations (circadian rhythms in DD2) were detected in at least part of the studied individuals of all species but S. typhlops, without a correlation with spectral powers of LD rhythms, i.e., individuals exhibiting residual oscillations were not necessarily those with the strongest LD rhythms. In conclusion, the accumulated evidence for troglobitic fishes strongly supports the hypothesis of external, environmental selection for circadian locomotor rhythms.

Gamma Irradiation of in-Shell and Blanched Peanuts Protects against Mycotoxic Fungi and Retains Their Nutraceutical Components during Long-Term Storage

Peanut samples were irradiated (0.0, 5.2, 7.2 or 10.0 kGy), stored for a year (room temperature) and examined every three months. Mycotoxic fungi (MF) were detected in non-irradiated blanched peanuts. A dose of 5.2 kGy was found suitable to prevent MF growth in blanched samples. No MF was detected in in-shell peanuts, with or without irradiation. The colors of the control in-shell and blanched samples were, respectively, 44.72 and 60.21 (L *); 25.20 and 20.38 (Chroma); 53.05 and 86.46 (degrees Hue). The water activities (Aw) were 0.673 and 0.425. The corresponding fatty acids were 13.33% and 12.14% (C16:0), 44.94% and 44.92% (C18:1,omega 9) and 37.10% and 37.63% (C18: 2,omega 6). The total phenolics (TP) were 4.62 and 2.52 mg GAE/g, with antioxidant activities (AA) of 16.97 and 10.36 mu mol TEAC/g. Storage time negatively correlated with Aw (in-shell peanuts) or L *, linoleic acid, TP and AA (in-shell and blanched peanuts) but positively correlated with Aw (blanched peanuts), and with oleic acid (in-shell and blanched peanuts). Irradiation positively correlated with antioxidant activity (blanched peanuts). No correlation was found between irradiation and AA (in-shell samples) or fatty acids and TP (in-shell and blanched peanuts). Irradiation protected against MF and retained both the polyunsaturated fatty acids and polyphenols in the samples.

Space-time relation of post-collisional granitic magmatism in Santa Catarina, southern Brazil: U-Pb LA-MC-ICP-MS zircon geochronology of coeval mafic-felsic magmatism related to the Major Gercino Shear Zone

LA-MC-ICP-MS U-Pb zircon dating was performed on syntectonic, early post-collisional granitic and associated mafic rocks that are intrusive in the Brusque Metamorphic Complex and in the Florianopolis Batholith, major tectonic domains separated by the Neoproterozoic Major Gercino Shear Zone (MGSZ) in south Brazil. The inferred ages of magmatic crystallization are consistent with field relationships, and show that the syntectonic granites from both domains are similar, with ages around 630-620 Ma for high-K calc-alkaline metaluminous granites and ca. 610 Ma for slightly peraluminous granites. Although ca. 650 Ma inherited zircon components are identified in granites from both domains, important contrasts on the crustal architecture in each domain are revealed by the patterns of zircon inheritance, indicating different crustal sources for the granites in each domain. The granites from the southern domain (Floriandpolis Batholith) have essentially Neoproterozoic (650-700 Ma and 900-950 Ma) inheritance; with a single 2.0-2.2 Ga inherited age obtained in the peraluminous Mariscal Granite. In the northern Brusque Metamorphic Complex, the metaluminous Rio Pequeno Granite and associated mafic rocks have scarce inherited cores with ages around 1.65 Ga, whereas the slightly peraluminous Serra dos Macacos Granite has abundant Paleoproterozoic (1.8-2.2 Ga) and Archean (2.9-3.4 Ga) inherited zircons. Our results are consistent with the hypothesis that the MGSZ separates domains with distinct geologic evolution; however, the contemporaneity of 630-610 Ma granitic magmatism with similar structural and geochemical patterns on both sides of this major shear zone indicates that these domains were already part of a single continental mass at 630 Ma, reinforcing the post-collisional character of these granites. (C) 2012 Elsevier B.V. All rights reserved.

Millennial-scale climate cycles in Permian-Carboniferous rhythmites: Permanent feature throughout geologic time?

Two late Paleozoic glacial rhythmite successions from the Itarare Group (Parana Basin, Brazil) were examined for paleoclimate variations. Paleomagnetic (characteristic remanent magnetization, ChRM) and magnetic susceptibility (K(z)) measurements taken from the rhythmites are interpreted as paleoclimatic proxies. Ratios of low-frequency components in the K(z) variations suggest Milankovitch periodicities; this leads to recognition of other, millennial-scale variations reminiscent of abrupt climate changes during late Quaternary time, and are suggestive of Bond cycles and the 2.4 k.y. solar cycle. We infer from these patterns that millennial-scale climate change is not restricted to the Quaternary Period, and that millennial forcing mechanisms may have been prevalent throughout geologic time.

Collybistin and gephyrin are novel components of the eukaryotic translation initiation factor 3 complex

Abstract Background Collybistin (CB), a neuron-specific guanine nucleotide exchange factor, has been implicated in targeting gephyrin-GABAA receptors clusters to inhibitory postsynaptic sites. However, little is known about additional CB partners and functions. Findings Here, we identified the p40 subunit of the eukaryotic translation initiation factor 3 (eIF3H) as a novel binding partner of CB, documenting the interaction in yeast, non-neuronal cell lines, and the brain. In addition, we demonstrated that gephyrin also interacts with eIF3H in non-neuronal cells and forms a complex with eIF3 in the brain. Conclusions Together, our results suggest, for the first time, that CB and gephyrin associate with the translation initiation machinery, and lend further support to the previous evidence that gephyrin may act as a regulator of synaptic protein synthesis.

Fatigue crack growth assessments in welded components including crack closure effects: Experiments and 3-D numerical modeling

This work provides a numerical and experimental investigation of fatigue crack growth behavior in steel weldments including crack closure effects and their coupled interaction with weld strength mismatch. A central objective of this study is to extend previously developed frameworks for evaluation of crack clo- sure effects on FCGR to steel weldments while, at the same time, gaining additional understanding of commonly adopted criteria for crack closure loads and their influence on fatigue life of structural welds. Very detailed non-linear finite element analyses using 3-D models of compact tension C ( T ) fracture spec- imens with center cracked, square groove welds provide the evolution of crack growth with cyclic stress intensity factor which is required for the estimation of the closure loads. Fatigue crack growth tests con- ducted on plane-sided, shallow-cracked C ( T ) specimens provide the necessary data against which crack closure effects on fatigue crack growth behavior can be assessed. Overall, the present investigation pro- vides additional support for estimation procedures of plasticity-induced crack closure loads in fatigue analyses of structural steels and their weldments

Sviluppo di un sistema miniaturizzato per il controllo real-time di assetto di nano e microsatelliti

Microsatelliti e nanosatelliti, come ad esempio i Cubesat, sono carenti di sistemi integrati di controllo d’assetto e di manovra orbitale. Lo scopo di questa tesi è stato quello di realizzare un sistema compatibile con Cubesat di una unità, completo di attuatori magnetici e attuatori meccanici, comprendente tutti i sensori e l’elettronica necessaria per il suo funzionamento, creando un dispositivo totalmente indipendente dal veicolo su cui è installato, capace di funzionare sia autonomamente che ricevendo comandi da terra. Nella tesi sono descritte le campagne di simulazioni numeriche effettuate per validare le scelte tecnologiche effettuate, le fasi di sviluppo dell’elettronica e della meccanica, i test sui prototipi realizzati e il funzionamento del sistema finale. Una integrazione così estrema dei componenti può implicare delle interferenze tra un dispositivo e l’altro, come nel caso dei magnetotorquer e dei magnetometri. Sono stati quindi studiati e valutati gli effetti della loro interazione, verificandone l’entità e la validità del progetto. Poiché i componenti utilizzati sono tutti di basso costo e di derivazione terrestre, è stata effettuata una breve introduzione teorica agli effetti dell’ambiente spaziale sull’elettronica, per poi descrivere un sistema fault-tolerant basato su nuove teorie costruttive. Questo sistema è stato realizzato e testato, verificando così la possibilità di realizzare un controller affidabile e resistente all’ambiente spaziale per il sistema di controllo d’assetto. Sono state infine analizzate alcune possibili versioni avanzate del sistema, delineandone i principali aspetti progettuali, come ad esempio l’integrazione di GPS e l’implementazione di funzioni di determinazione d’assetto sfruttando i sensori presenti a bordo.

What are the components that contribute to variability in echocardiographic measurements in aortic stenosis?

INTRODUCTION Echocardiography is the standard clinical approach for quantification of the severity of aortic stenosis (AS). A comprehensive examination of its overall reproducibility and the simultaneous estimation of its variance components by multiple operators, readers, probe applications, and beats have not been undertaken. METHOD AND RESULTS Twenty-seven subjects with AS were scanned over 7 months in the echo-department by a median of 3 different operators. From each patient and each operator multiple runs of beats from multiple probe positions were stored for later analysis by multiple readers. The coefficient of variation was 13.3%, 15.9%, 17.6%, and 20.2% for the aortic peak velocity (Vmax), and velocity time integral (VTI), and left ventricular outflow tract (LVOT) Vmax and VTI respectively. The largest individual contributors to the overall variability were the beat-to-beat variability (9.0%, 9.3%, 9.5%, 9.4% respectively) and that of inability of an individual operator to precisely apply the probe to the same position twice (8.3%, 9.4%, 12.9%, 10.7% respectively). The tracing (inter-reader) and reader (inter-reader), and operator (inter-operator) contribution were less important. CONCLUSIONS Reproducibility of measurements in AS is poorer than often reported in the literature. The source of this variability does not appear, as traditionally believed, to result from a lack of training or operator and reader specific factors. Rather the unavoidable beat-to-beat biological variability, and the inherent impossibility of applying the ultrasound probe in exactly the same position each time are the largest contributors. Consequently, guidelines suggesting greater standardisation of procedures and further training for sonographers are unlikely to result in an improvement in precision. Clinicians themselves should be wary of relying on even three-beat averages as their expected coefficient of variance is 10.3% for the peak velocity at the aortic valve.

Phenotypic characterization of the epithelial and myoepithelial components in canine and feline mammary tumours

In veterinary medicine, the ability to classify mammary tumours based on the molecular profile and also determine whether the immunophenotype of the regional lymph node and/or systemic metastases is equal to that of the primary tumor may be predictive on the estimation of the effectiveness of various cancer treatments that can be scheduled. Therefore, aims, developed as projects, of the past three years have been (1) to define the molecular phenotype of feline mammary carcinomas and their lymph node metastases according to a previous modified algorithm and to demonstrate the concordance or discordance of the molecular profile between the primary tumour and lymph node metastasis, (2) to analyze, in female dogs, the relationship between the primary mammary tumor and its lymph node metastasis based on immunohistochemical molecular characterization in order to develop the most specific prognostic-predictive models and targeted therapeutic options, and (3) to evaluate the molecular trend of cancer from its primary location to systemic metastases in three cats and two dogs with mammary tumors. The studies on mammary tumours, particularly in dogs, have drawn gradually increasing attention not exclusively to the epithelial component, but also to the myoepithelial cells. The lack of complete information on a valid panel of markers for the identification of these cells in the normal and neoplastic mammary gland and lack of investigation of immunohistochemical changes from an epithelial to a mesenchymal phenotype, was the aim of a parallel research. While investigating mammary tumours, it was noticed that only few studies had focused on the expression of CD117. Therefore, it was decided to further deepen the knowledge in order to characterize the immunohistochemical staining of CD117 in normal and neoplastic mammary tissue of the dog, and to correlate CD117 immunohistochemical results with mammary histotype, histological stage (invasiveness), Ki67 index and patient survival time.

Type Systems for Distributed Programs: Components and Sessions

Modern software systems, in particular distributed ones, are everywhere around us and are at the basis of our everyday activities. Hence, guaranteeing their cor- rectness, consistency and safety is of paramount importance. Their complexity makes the verification of such properties a very challenging task. It is natural to expect that these systems are reliable and above all usable. i) In order to be reliable, compositional models of software systems need to account for consistent dynamic reconfiguration, i.e., changing at runtime the communication patterns of a program. ii) In order to be useful, compositional models of software systems need to account for interaction, which can be seen as communication patterns among components which collaborate together to achieve a common task. The aim of the Ph.D. was to develop powerful techniques based on formal methods for the verification of correctness, consistency and safety properties related to dynamic reconfiguration and communication in complex distributed systems. In particular, static analysis techniques based on types and type systems appeared to be an adequate methodology, considering their success in guaranteeing not only basic safety properties, but also more sophisticated ones like, deadlock or livelock freedom in a concurrent setting. The main contributions of this dissertation are twofold. i) On the components side: we design types and a type system for a concurrent object-oriented calculus to statically ensure consistency of dynamic reconfigurations related to modifications of communication patterns in a program during execution time. ii) On the communication side: we study advanced safety properties related to communication in complex distributed systems like deadlock-freedom, livelock- freedom and progress. Most importantly, we exploit an encoding of types and terms of a typical distributed language, session π-calculus, into the standard typed π- calculus, in order to understand their expressive power.