Passive acoustic quantification of gas releases

The assessment of undersea gas leakages from anthropogenic and natural sources is becoming increasingly important. This includes the detection of gas leaks and the quantification of gas flux. This has applications within oceanography (e.g. natural methane seeps) and the oil and gas industry (e.g. leaks from undersea gas pipelines, carbon capture and storage facilities). Gas escaping underwater can result in the formation of gas bubbles, and this leads to specific acoustic pressure fluctuations (sound) which can be analysed using passive acoustic systems. Such a technique offers the advantage of lower electrical power requirements for long term monitoring. It is common practice for researchers to identify single bubble injection events from time histories or time frequency representations of hydrophone data, and infer bubble sizes from the centre frequency of the emission. Such a technique is well suited for gas releases that represent low flow rates, and involving solitary bubble release. However, for larger events, with the overlapping of bubble acoustic emissions, the inability to discriminate each individual bubble injection event makes this approach inappropriate. In this study, an inverse method to quantify such release is used. The model is first outlined and following this its accuracy at different flow rate regimes is tested against experimental data collected from tests which took place in a large water tank. The direct measurements are compared to estimates inferred from acoustics.<br/

Ethical challenges in palliative sedation of adults: protocol for a systematic review of current clinical practice guidelines.

This study aims to identify the full spectrum of ethical challenges of all forms of palliative sedation for adults as presented in current clinical practice guidelines (CPGs) and to determine whether CPGs specify ethical challenges of this therapy for patients with cancer and non-cancer and, if so, how exactly they do this. To the best of our knowledge, no studies have yet investigated this topic. The purpose is purely descriptive; our aim is not to make any kind of normative judgements on these challenges. Nor is our aim to assess the quality of the CPGs. We will perform a systematic review of CPGs on palliative sedation for adults via five electronic databases, grey literature search tools, citation tracking and contact with palliative care experts. Current CPGs accredited by an international, national or regional authority, published in English, German, French, Italian or Polish, from 2000 to the date of the search, will be subjected to content analysis at the textual, linguistic and thematic levels. This is a protocol for a systematic review and no human will be involved in this research. Therefore, ethics approval and consent to participate are not applicable to this context. This study protocol is reported in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis for Protocols criteria and registered on PROSPERO. Moreover, the integral version of this study protocol is published as a preprint on Research Square. The results of this study will be actively disseminated through peer-reviewed journals and books, international, national and local conference presentations, social media and media in general

Anatomical variations of knee ligaments in magnetic resonance imaging: pictorial essay

Evaluation with magnetic resonance imaging (MRI) is currently a gold standard for comprehensive posttraumatic assessment of the knee joint. Increasing availability of MR systems with stronger magnetic fields and new sequences results in higher resolution of images and thus allows imaging smaller and finer anatomical details, including different anatomical variations. This article focuses on anatomical variations of knee ligaments, which can mimics pathological structures. Well-known and less common ligaments that are sporadically observed and may raise the most doubt will be discussed. Familiarity with those variations of ligaments is indispensable for precise MRI reporting to avoid misinterpretation as meniscal tears, loose bodies or mass lesions especially in cases. This paper is addressed to both radiology and orthopaedics specialists. Illustrations show discussed ligaments in standard planes while, for less known ligaments, we add information on how to adjust planes to properly visualise a particular structure, which will hopefully facilitate finding and differentiating those structures in clinical practice

The analysis of solar models: Neutrinos and oscillations

Tests of solar neutrino flux and solar oscillation frequencies were used to assess standard stellar structure theory. Standard and non-standard solar models are enumerated and discussed. The field of solar seismology, wherein the solar interior is studied from the measurement of solar oscillations, is introduced

From Forbidden Coronal Lines to Meaningful Coronal Magnetic Fields

We review methods to measure magnetic fields within the corona using the polarized light in magnetic-dipole (M1) lines. We are particularly interested in both the global magnetic-field evolution over a solar cycle, and the local storage of magnetic free energy within coronal plasmas. We address commonly held skepticisms concerning angular ambiguities and line-of-sight confusion. We argue that ambiguities are in principle no worse than more familiar remotely sensed photospheric vector-fields, and that the diagnosis of M1 line data would benefit from simultaneous observations of EUV lines. Based on calculations and data from eclipses, we discuss the most promising lines and different approaches that might be used. We point to the S-like [Fe {\sc XI}] line (J=2 to J=1) at 789.2nm as a prime target line (for ATST for example) to augment the hotter 1074.7 and 1079.8 nm Si-like lines of [Fe {\sc XIII}] currently observed by the Coronal Multi-channel Polarimeter (CoMP). Significant breakthroughs will be made possible with the new generation of coronagraphs, in three distinct ways: (i) through single point inversions (which encompasses also the analysis of MHD wave modes), (ii) using direct comparisons of synthetic MHD or force-free models with polarization data, and (iii) using tomographic techniques.Comment: Accepted by Solar Physics, April 201

Atmospheric circulation conditions during winter warm spells in Central Europe

The objective of the paper was to characterise the temporal and spatial variability of winter warm spells in Central Europe in the years 1966/1967-2015/2016 and to determine the circulation conditions of their occurrence. The applied data were obtained from the Polish Institute of Meteorology and Water Management, Deutscher Wetterdienst and the National Centre for Environmental Prediction/National Centre for Atmospheric Research. A warm spell was defined as a sequence of at least three warm days, i.e. when the maximum air temperature is higher than the 95th percentile of the probability density function designated from observation. The research has proven that over the study period the air temperature increased in the winter season in Central Europe and this translated into an increase in the number of warm days. An average of 3-5 warm spells was recorded per 10 years. The most numerous warm spells occurred during three winter seasons, i.e. 1989/1990, 2006/2007 and 2015/2016. The occurrence of warm spells was related to positive anomalies of geopotential heights over the study area in the cross section of the entire troposphere. Maximum anomalies appeared at 250 hPa geopotential height, and they developed on average 9 days before the commencement of warm spells over the study area

Patterns in the multiannual course of growing season in Central Europe since the end of the 19th century

The research identified patterns in the multiannual course of start and end dates, and length of growing sea son (GS) in Central Europe since the end of the 19th century in selected cities of Central Europe in the period 1893-2020. GS start in the analysed stations was characterised by high year-to-year variability, particularly in those located more southwards, i.e. in Prague and Vienna. A smaller variability occurred in GS end dates. The GS was subject to prolon gation, although these changes in particular cities were uneven and had different causes. In Toruń and Potsdam, its increase was caused by a greater shift of the end date, and in the remaining stations, it was determined by its earlier start date. Two subperiods were distinguished that differ in terms of intensity of changes of the start and end dates, as well as the length of the GS. The intensification was observed recently

Smartphone Distraction: Italian Validation of the Smartphone Distraction Scale (SDS)

This work aimed to validate the use of the Smartphone Distraction Scale (SDS) in Italy. The SDS was devised to assess distraction related to smartphone use in adult populations. A cross-sectional study was conducted among n = 609 adults (females = 76.4%; mean age = 30.26; SD age = 9.90). An assessment of the factorial structure of the Italian version was carried out using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The four factors identified by Throuvala and colleagues were confirmed (i.e., attention impulsiveness, online vigilance, multitasking and emotion regulation). Reliability was assessed using Cronbach's alpha coefficient (0.703-0.889). The scale's scores showed significant linear correlations with validated instruments, including the Mobile Phone Problematic Use Scale (MPPUS)and the Cognitive Failures Questionnaire (CFQ). A multivariate analysis of variance showed significant differences in the means among participants belonging to different age groups (born before 1995 vs. born after 1996). In summary, the good psychometric properties observed led us to assume that this instrument can be applied and used in Italian studies to assess the cognitive dimension of distraction related to the use of smartphones