Ultrasonic guided waves propagation analysis under different load tension levels in multi-wire cables

Power line structures made of multi-wire cables are normally subject to adverse environmental conditions that can affect their integrity. The applicability of several techniques has been studied as a possible structural health monitoring solution. Amongst these, Ultrasonic Guided Waves have shown great potential. The complex geometry of the multi-element cable structures complicates the waves’ propagation behaviour and therefore the signal analysis, making the monitoring of the structural integrity of the cables a challenging task. This research presents the enhancements obtained through the use of a specially designed multiple transducer collar for the inspection of the wires. The waves’ excitation capabilities of the system are experimentally evaluated under different axial unload and load tension levels. The influence of these conditions on wave propagation is analysed. The results show the technique’s long range capabilities as well as its limitations and will thereby contribute towards the design of a future structural health monitoring system.This work is part of MOSAIC project, funded by the UK government under the Innovate UK Programme. MOSAIC is a collaboration between the following organisations: Plant Integrity Ltd (Pi), Brunel Innovation Centre (BIC) Brunel University London, and Applied Inspection® (AI)

Gamma distribution function to understand anaerobic digestion kinetics: Kinetic constants are not constant

The Gamma model is a novel approach to characterise the complex degradation dynamics taking place during anaerobic digestion. This three parameters model results from combining the first-order kinetic model and the Gamma distribution function. In contrast to conventional models, where the kinetic constant is considered invariant, the Gamma model allows analysing the variability of the kinetic constant using a probability density function. The kinetic constant of mono-digestion and co-digestion batch tests of different wastes were modelled using the Gamma model and two common first-order models: one-step one-fraction model and one-step two-fraction model. The Gamma distribution function approximates three distinct probability density functions, i.e. exponential, log-normal, and delta Dirac. Specifically, (i) cattle paunch and pig manure approximated a log-normal distribution; (ii) cattle manure and microalgae approximated an exponential distribution, and (iii) primary sludge and cellulose approximated a delta Dirac distribution. The Gamma model was able to characterise two distinct waste activated sludge, one approximated to a log-normal distribution and the other to an exponential distribution. The same cellulose was tested with two different inocula; in both tests, the Gamma distribution function approximated a delta Dirac function but with a different kinetic value. The potential and consistency of Gamma model were also evident when analysing pig manure and microalgae co-digestion batch tests since (i) the mean k of the co-digestion tests were within the values of the mono-digestion tests, and (ii) the profile of the density function transitioned from log-normal to exponential distribution as the percentage of microalgae in the mixture increased

Development of the Pajonales landslide (Tirajana Depression, Gran Canaria): a case of progressive partial reactivation

Se ha estudiado la evolución de las distintas fases del deslizamiento de Pajonales (barranco de Tirajana, Gran Canaria), a partir de las características geotécnicas de los materiales volcánicos in situ y deslizados. Para ello, se recogieron muestras de piroclastos y suelos representativos de las masas deslizadas y se realizaron ensayos de identificación y resistencia al corte. Se ha reconstruido la morfología de la ladera previa al deslizamiento a partir de las superficies deslizadas y de los escarpes de primera y segunda generación. Mediante un programa de análisis del equilibrio límite se han identificado las superficies de rotura para cada una de las fases del deslizamiento. Estas superficies se han desarrollado a través de niveles limo-arcillosos, que son producto de la alteración de los materiales piroclásticos, y que presentan las propiedades geotécnicas más desfavorables (valores mínimos o residuales). Por otra parte, se verificó que la presencia de agua constituye un factor desencadenante del deslizamiento, ya que es necesaria la saturación total o parcial de los materiales. Por último, el deslizamiento es de tipo progresivo: a medida que se producen las sucesivas reactivaciones, las masas ya deslizadas se descomponen en otras más pequeñas que se desplazan, ladera abajo, hacia el centro del barranco.We have studied the evolution of the different stages of Pajonales landslide (Tirajana ravine, Gran Canaria), from the geotechnical characteristics of in situ and mobilized volcanic materials. Representative samples of pyroclasts and soils from landslides were collected and laboratory tests were performed to determine the shear strength. The morphology of slope prior to sliding was reconstructed considering the location of the failure surfaces and scarps of first and second generation. Failure surfaces for each stage of sliding were identified using a program of limit equilibrium analysis. These surfaces have been developed through clayey silt levels that result from the alteration of pyroclastic materials, showing the most unfavourable geotechnical properties (minimal or residual values). Moreover, the presence of water is a triggering factor, since total or partial saturation of the materials is required. Finally, the landslide is a progressive type: as successive reactivations occur, the sliding masses are broken down into smaller ones moving towards the Tirajana ravine.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEUniversidad Complutense de Madridpu

Development of the Platysma Muscle and the Superficial Musculoaponeurotic System (Human Specimens at 8–17 Weeks of Development)

There is controversy regarding the description of the different regions of the face of the superficial musculoaponeurotic system (SMAS) and its relationship with the superficial mimetic muscles. The purpose of this study is to analyze the development of the platysma muscle and the SMAS in human specimens at 8–17 weeks of development using an optical microscope. Furthermore, we propose to study the relationship of the anlage of the SMAS and the neighbouring superficial mimetic muscles. The facial musculature derives from the mesenchyme of the second arch and migrates towards the different regions of the face while forming premuscular laminae. During the 8th week of development, the cervical, infraorbital, mandibular, and temporal laminae are observed to be on the same plane. The platysma muscle derives from the cervical lamina and its mandibular extension enclosing the lower part of the parotid region and the cheek, while the SMAS derives from the upper region. During the period of development analyzed in this study, we have observed no continuity between the anlage of the SMAS and that of the superficial layer of the temporal fascia and the zygomaticus major muscle. Nor have we observed any structure similar to the SMAS in the labial region

The novel genus, ‘Candidatus Phosphoribacter’, previously identified as Tetrasphaera, is the dominant polyphosphate accumulating lineage in EBPR wastewater treatment plants worldwide

The bacterial genus Tetrasphaera encompasses abundant polyphosphate accumulating organisms (PAOs) that are responsible for enhanced biological phosphorus removal (EBPR) in wastewater treatment plants. Recent analyses of genomes from pure cultures revealed that 16S rRNA genes cannot resolve the lineage, and that Tetrasphaera spp. are from several different genera within the Dermatophilaceae. Here, we examine 14 recently recovered high-quality metagenome-assembled genomes from wastewater treatment plants containing full-length 16S rRNA genes identified as Tetrasphaera, 11 of which belong to the uncultured Tetrasphaera clade 3. We find that this clade represents two distinct genera, named here Ca. Phosphoribacter and Ca. Lutibacillus, and reveal that the widely used model organism Tetrasphaera elongata is less relevant for physiological predictions of this uncultured group. Ca. Phosphoribacter incorporates species diversity unresolved at the 16S rRNA gene level, with the two most abundant and often co-occurring species encoding identical V1-V3 16S rRNA gene amplicon sequence variants but different metabolic capabilities, and possibly, niches. Both Ca. P. hodrii and Ca. P. baldrii were visualised using fluorescence in situ hybridisation (FISH), and PAO capabilities were confirmed with FISH-Raman microspectroscopy and phosphate cycling experiments. Ca. Phosphoribacter represents the most abundant former Tetrasphaera lineage and PAO in EPBR systems in Denmark and globally

Nocturnal Hypoxemia and CT Determined Pulmonary Artery Enlargement in Smokers

Background: Pulmonary artery enlargement (PAE) detected using chest computed tomography (CT) is associated with poor outcomes in chronic obstructive pulmonary disease (COPD). It is unknown whether nocturnal hypoxemia occurring in smokers, with or without COPD, obstructive sleep apnoea (OSA) or their overlap, may be associated with PAE assessed by chest CT. Methods: We analysed data from two prospective cohort studies that enrolled 284 smokers in lung cancer screening programs and completing baseline home sleep studies and chest CT scans. Main pulmonary artery diameter (PAD) and the ratio of the PAD to that of the aorta (PA:Ao ratio) were measured. PAE was defined as a PAD >= 29 mm in men and >= 27 mm in women or as a PA:Ao ratio > 0.9. We evaluated the association of PAE with baseline characteristics using multivariate logistic models. Results: PAE prevalence was 27% as defined by PAD measurements and 11.6% by the PA:Ao ratio. A body mass index >= 30 kg/m(2) (OR 2.01; 95%CI 1.06-3.78), lower % predicted of forced expiratory volume in one second (FEV1) (OR 1.03; 95%CI 1.02-1.05) and higher % of sleep time with O-2 saturation < 90% (T90) (OR 1.02; 95%CI 1.00-1.03), were associated with PAE as determined by PAD. However, only T90 remained significantly associated with PAE as defined by the PA:Ao ratio (OR 1.02; 95%CI 1.01-1.03). In the subset group without OSA, only T90 remains associated with PAE, whether defined by PAD measurement (OR 1.02; 95%CI 1.01-1.03) or PA:Ao ratio (OR 1.04; 95%CI 1.01-1.07). Conclusions: In smokers with or without COPD, nocturnal hypoxemia was associated with PAE independently of OSA coexistence

Linking Whole-Slide Microscope Images with DICOM by Using JPEG2000 Interactive Protocol

The use of digitized histopathologic specimens (also known as whole-slide images (WSIs)) in clinical medicine requires compatibility with the Digital Imaging and Communications in Medicine (DICOM) standard. Unfortunately, WSIs usually exceed DICOM image object size limit, making it impossible to store and exchange them in a straightforward way. Moreover, transmitting the entire DICOM image for viewing is ineffective for WSIs. With the JPEG2000 Interactive Protocol (JPIP), WSIs can be linked with DICOM by transmitting image data over an auxiliary connection, apart from patient data. In this study, we explored the feasibility of using JPIP to link JPEG2000 WSIs with a DICOM-based Picture Archiving and Communications System (PACS). We first modified an open-source DICOM library by adding support for JPIP as described in the existing DICOM Supplement 106. Second, the modified library was used as a basis for a software package (JVSdicom), which provides a proof-of-concept for a DICOM client–server system that can transmit patient data, conventional DICOM imagery (e.g., radiological), and JPIP-linked JPEG2000 WSIs. The software package consists of a compression application (JVSdicom Compressor) for producing DICOM-compatible JPEG2000 WSIs, a DICOM PACS server application (JVSdicom Server), and a DICOM PACS client application (JVSdicom Workstation). JVSdicom is available for free from our Web site (http://jvsmicroscope.uta.fi/), which also features a public JVSdicom Server, containing example X-ray images and histopathology WSIs of breast cancer cases. The software developed indicates that JPEG2000 and JPIP provide a well-working solution for linking WSIs with DICOM, requiring only minor modifications to current DICOM standard specification