A Modelling Study for Smart Pigging Technique for Pipeline Leak Detection

Although leak incidents continue, a pipeline remains the most reliable mode of transportation within the oil and gas industry. It becomes even more important today because the projection for new pipelines is expected to increase by 1 billion BOE through 2035. In addition, increasing number and length of subsea tiebacks face new challenges in term of data acquisition, monitoring, analysis, and remedial actions. Passive leak-detection methods commonly used in the industry have been successful with some limitations in that they often cannot detect small leaks and seeps. In addition to a thorough review of related topics, this study investigates how to create a framework for a smart pigging technique for pipeline leak detection, as an active leak detection method. Numerical modeling of smart pigging for leak detection requires two crucial components: detailed mathematical descriptions for fluid-solid and solid-solid interactions around pig, and network modeling for the calculation of pressure and rate along the pipeline using iterative algorithms. The first step of this study is to build a numerical model that shows the motion of a pig along the pipeline with no leak, i.e., at a given injection rate, a pig first accelerates until it reaches its terminal velocity, beyond which the pig moves at a constant velocity. The second step is to construct a network model that consists of two pipeline segments (one upstream and the other downstream of leak location) through which the pig travels and at the junction of which fluid leak occurs. By putting these multiple mechanisms together and using resulting pressure signatures, this study presents a new method to predict the location and size of a leak present in pipeline

In vivo endoscopic autofluorescence microspectro-imaging of bronchi and alveoli

Fibered confocal fluorescence microscopy (FCFM) is a new technique that can be used during a bronchoscopy to analyze the nature of the human bronchial and alveolar mucosa fluorescence microstructure. An endoscopic fibered confocal fluorescence microscopy system with spectroscopic analysis capability was developed allowing real-time, simultaneous images and emission spectra acquisition at 488 nm excitation using a flexible miniprobe that could be introduced into small airways. This flexible 1.4 mm miniprobe can be introduced into the working channel of a flexible endoscope and gently advanced through the bronchial tree to the alveoli. FCFM in conjunction with bronchoscopy is able to image the in vivo autofluorescence structure of the bronchial mucosae but also the alveolar respiratory network outside of the usual field of view. Microscopic and spectral analysis showed that the signal mainly originates from the elastin component of the bronchial subepithelial layer. In non smokers, the system images the elastin backbone of the aveoli. In active smokers, a strong autofluorescence signal appears from alveolar macrophages. The FCFM technique appears promising for in vivo exploration of the bronchial and alveolar extracellular matrix

Le dépistage de la dépression du post-partum par l Edinburgh Postnatal Depression Scale (EPDS) (Enquête auprès de 52 médecins généralistes Haut-Normands sur l intérêt et l utilisation pratique de cet outil)

La dépression du post-partum est fréquente, affectant 10 à 15% des femmes dans l année qui suit l accouchement. Ses conséquences sur les interactions mère-bébé et sur le développement de l enfant peuvent être graves, son dépistage représente donc un réel enjeu. Pourtant, la dépression du post-partum est méconnue par les médecins, et son diagnostic est limité par le défaut d expression spontanée des mères. Un outil de dépistage présenté sous forme d auto-questionnaire a été conçu en Ecosse en 1987 et validé en France en 1998: l Edinburgh Postnatal Depression Scale (EPDS). Destiné aux professionnels de premiers recours, il est souvent utilisé dans les études de recherche, mais très rarement en pratique médicale courante. Nous avons voulu savoir si l outil EPDS présentait un intérêt pour les médecins généralistes. Notre enquête a recueilli l avis de 52 médecins généralistes Haut-Normands. Ils ont testé la faisabilité de distribution, de cotation et d interprétation de l EPDS, au cours de consultations non dédiées, quand une jeune mère consultait pour elle-même ou pour son nourrisson de moins d un an. Nous avons récupéré 299 EPDS, chaque médecin ayant distribué 6 EPDS en moyenne avant de donner son opinion. Nos résultats indiquent que l EPDS est un outil bien accepté par les patientes, d interprétation aisée et facile à administrer en médecine générale. Il est jugé utile par une majorité de médecins. Un médecin sur quatre ne souhaite cependant pas le réutiliser dans sa pratique quotidienne. Certains préfèrent aborder le sujet délicat des troubles de l humeur du post-partum par le dialogue, d autres avancent le manque de temps comme principal frein à l utilisation de l EPDS. Les médecins qui souhaitent réutiliser l EPDS le feront en majorité occasionnellement, quand ils auront des doutes sur l état psychologique d une mère, et non comme dépistage systématique. Pour mieux repérer les dépressions du post-partum, la passation de l EPDS peut être utile dans un but d écoute et d ouverture, en privilégiant un espace authentique de parole. La consultation postnatale, entre la 6ème et la 8ème semaine après l accouchement, représente une période propice au dépistage. Pour compléter la diffusion de l EPDS auprès des omnipraticiens, la formation des médecins et l efficacité d un réseau de soins centré sur la dyade mère-enfant sont indispensables.ROUEN-BU Médecine-Pharmacie (765402102) / SudocSudocFranceF

Diagnostic issues and capabilities in 48 isolation facilities in 16 European countries: data from EuroNHID surveys

Background: Highly infectious diseases (HIDs) are defined as being transmissible from person to person, causing life-threatening illnesses and presenting a serious public health hazard. The sampling, handling and transport of specimens from patients with HIDs present specific bio-safety concerns. Findings The European Network for HID project aimed to record, in a cross-sectional study, the infection control capabilities of referral centers for HIDs across Europe and assesses the level of achievement to previously published guidelines. In this paper, we report the current diagnostic capabilities and bio-safety measures applied to diagnostic procedures in these referral centers. Overall, 48 isolation facilities in 16 European countries were evaluated. Although 81% of these referral centers are located near a biosafety level 3 laboratory, 11% and 31% of them still performed their microbiological and routine diagnostic analyses, respectively, without bio-safety measures. Conclusions: The discrepancies among the referral centers surveyed between the level of practices and the European Network of Infectious Diseases (EUNID) recommendations have multiple reasons of which the interest of the individuals in charge and the investment they put in preparedness to emerging outbreaks. Despite the fact that the less prepared centers can improve by just updating their practice and policies any support to help them to achieve an acceptable level of biosecurity is welcome

Development of a nonlinear fiber-optic spectrometer for human lung tissue exploration

Several major lung pathologies are characterized by early modifications of the extracellular matrix (ECM) fibrillar collagen and elastin network. We report here the development of a nonlinear fiber-optic spectrometer, compatible with an endoscopic use, primarily intended for the recording of second-harmonic generation (SHG) signal of collagen and two-photon excited fluorescence (2PEF) of both collagen and elastin. Fiber dispersion is accurately compensated by the use of a specific grism-pair stretcher, allowing laser pulse temporal width around 70 fs and excitation wavelength tunability from 790 to 900 nm. This spectrometer was used to investigate the excitation wavelength dependence (from 800 to 870 nm) of SHG and 2PEF spectra originating from ex vivo human lung tissue samples. The results were compared with spectral responses of collagen gel and elastin powder reference samples and also with data obtained using standard nonlinear microspectroscopy. The excitation-wavelength-tunable nonlinear fiber-optic spectrometer presented in this study allows performing nonlinear spectroscopy of human lung tissue ECM through the elastin 2PEF and the collagen SHG signals. This work opens the way to tunable excitation nonlinear endomicroscopy based on both distal scanning of a single optical fiber and proximal scanning of a fiber-optic bundle

IN VIVO CONFOCAL MICROENDOSCOPY: FROM THE PROXIMAL BRONCHUS DOWN TO THE PULMONARY ACINUS

In vivo endoscopic microscopy aims to provide the clinician with a tool to assess architecture and morphology of a living tissue in real time, with an optical resolution similar to standard histopathology. To date, available microendoscopic devices use the principle of fluorescence confocal microscopy, and thereby mainly analyse the spatial distribution of specific endogenous or exogenous fluorophores. Fluorescence microendoscopes devoted to respiratory system exploration use a bundle of optical fibres, introduced into the working channel of the bron- choscope. This miniprobe can be applied in vivo onto the bronchial inner surface or advanced into a distal bron- chiole down to the acinus, to produce in situ, in vivo microscopic imaging of the respiratory tract in real time. Fluorescence confocal microendoscopy has the capability to image the epithelial and subepithelial layers of the pro- ximal bronchial tree, as well as the more distal parts of the lungs, from the terminal bronchioles down to the alveolar ducts and sacs. Potential applications include in vivo microscopic assessment of early bronchial cancers, bronchial wall remodelling evaluation and diffuse peripheral lung disease exploration, as well as in vivo diagnosis of peripheral lung nodules. The technique has also the potential to be coupled with fluorescence molecular imaging. This chapter de- scribes the capabilities and possible limitations of confocal microendoscopy for proximal and distal lung exploration

Double-clad fiber with a tapered end for confocal endomicroscopy

We present a double-clad fiber coupler (DCFC) for use in confocal endomicroscopy to reduce speckle contrast, increase signal collection while preserving optical sectioning. The DCFC is made by incorporating a double-clad tapered fiber (DCTF) to a fused-tapered DCFC for achromatic transmission (from 1265 nm to 1325 nm) of > 95% illumination light trough the single mode (SM) core and collection of > 40% diffuse light through inner cladding modes. Its potential for confocal endomicroscopy is demonstrated in a spectrally-encoded imaging setup which shows a 3 times reduction in speckle contrast as well as 5.5 × increase in signal collection compared to imaging with a SM fiber

Comprehensive volumetric confocal microscopy with adaptive focusing

Comprehensive microscopy of distal esophagus could greatly improve the screening and surveillance of esophageal diseases such as Barrett’s esophagus by providing histomorphologic information over the entire region at risk. Spectrally encoded confocal microscopy (SECM) is a high-speed reflectance confocal microscopy technology that can be configured to image the entire distal esophagus by helically scanning the beam using optics within a balloon-centering probe. It is challenging to image the human esophagus in vivo with balloon-based SECM, however, because patient motion and anatomic tissue surface irregularities decenter the optics, making it difficult to keep the focus at a predetermined location within the tissue as the beam is scanned. In this paper, we present a SECM probe equipped with an adaptive focusing mechanism that can compensate for tissue surface irregularity and dynamic focal variation. A tilted arrangement of the objective lens is employed in the SECM probe to provide feedback signals to an adaptive focusing mechanism. The tilted configuration also allows the probe to obtain reflectance confocal data from multiple depth levels, enabling the acquisition of three-dimensional volumetric data during a single scan of the probe. A tissue phantom with a surface area of 12.6 cm2 was imaged using the new SECM probe, and 8 large-area reflectance confocal microscopy images were acquired over the depth range of 56 μm in 20 minutes. Large-area SECM images of excised swine small intestine tissue were also acquired, enabling the visualization of villous architecture, epithelium, and lamina propria. The adaptive focusing mechanism was demonstrated to enable acquisition of in-focus images even when the probe was not centered and the tissue surface was irregular