An evaluation of the relative efficacy of an open airway, an oxygen reservoir and continuous positive airway pressure 5 cmH2O on the non-ventilated lung

Publisher's copy made available with the permission of the publisher © Australian Society of AnaesthetistsThe aim of this study, during one-lung ventilation, was to evaluate if oxygenation could be improved by use of a simple oxygen reservoir or application of 5 cmH2O continuous positive airway pressure (CPAP) to the non-ventilated lung compared with an open airway. Twenty-three patients with lung malignancy, undergoing thoracotomy requiring at least 60 minutes of one-lung ventilation before lung lobe excision, were studied. After routine induction and establishment of one-lung ventilation, the three treatments were applied in turn to the same patient in a sequence selected randomly. The first treatment was repeated as a fourth treatment and these results of the repeated treatment averaged to minimize the effect of slow changes. Arterial oxygenation was measured by an arterial blood gas 15 minutes after the application of each treatment. Twenty patients completed the study. Mean PaO2 (in mmHg) was 210.3 (SD 105.5) in the 'OPEN' treatment, 186.0 (SD 109.2) in the 'RESERVOIR' treatment, and 240.5 (SD 116.0) in the 'CPAP' treatment. This overall difference was not quite significant (P=0.058, paired ANOVA), but comparison of the pairs showed that there was a significant better oxygenation only with the CPAP compared to the reservoir treatments (t=2.52, P=0.021). While the effect on the surgical field was not apparent in most patients, in one patient surgery was impeded during CPAP. Our results show that the use of a reservoir does not give oxygenation better than an open tube, and is less effective than the use of CPAP 5 cmH2O on the non-ventilated lung during one-lung ventilation.J. Slimani, W. J. Russell, C. Jurisevichttp://www.aaic.net.au/Article.asp?D=200404

A low power photoemission source for electrons on liquid helium

Electrons on the surface of liquid helium are a widely studied system that may also provide a promising method to implement a quantum computer. One experimental challenge in these studies is to generate electrons on the helium surface in a reliable manner without heating the cryo-system. An electron source relying on photoemission from a zinc film has been previously described using a high power continuous light source that heated the low temperature system. This work has been reproduced more compactly by using a low power pulsed lamp that avoids any heating. About 5e3 electrons are collected on 1 cm^2 of helium surface for every pulse of light. A time-resolved experiment suggests that electrons are either emitted over or tunnel through the 1eV barrier formed by the thin superfluid helium film on the zinc surface. No evidence of trapping or bubble formation is seen.Comment: 9 pages, 3 figures, submitted to J. Low Temp. Phy

Nanostructure of CaO-(Na2O)-Al2O3-SiO2-H2O gels revealed by multinuclear solid-state magic angle spinning and multiple quantum magic angle spinning nuclear magnetic resonance spectroscopy

(Calcium,alkali)-aluminosilicate gel frameworks are the basis of modern cements and alkali-activated materials for sustainable infrastructure and radioactive waste immobilization and also find application in glass alteration, mineral weathering, and zeolite synthesis. Here, we resolve the nanostructure of these gels that dictates mass transport, solubility, and mechanical properties. The key structural motifs comprising hydrous (calcium,alkali)-aluminosilicate gels are identified via 17O, 23Na, and 27Al triple-quantum magic angle spinning and 29Si magic angle spinning nuclear magnetic resonance spectroscopy of a novel class of stoichiometrically controlled 17O-enriched multiphase gels. Increased Ca content promotes low-Al, high-Ca chain-structured “C-S-H-type” products exhibiting significant nanostructural ordering, low levels of chain cross-linking, predominant Ca coordination of nonbridging oxygen atoms, and an increase in proton association with CaO layers to form Ca–OH sites. Al substitution is identified in multiple sites in the silicate chains, including cross-linking, bridging, and pairing tetrahedra. Increased Al content increases the proportion of cross-linking sites and gel disorder. The large increase in SiIV–O–AlIV sites increases the relative amounts of Na+ and AlV species charge-balancing AlO4– tetrahedra and results in the formation of an additional disordered low-calcium, framework-structured alkali aluminosilicate (“N-A-S-H-type”) gel, with high Al and Na contents. Changes in bulk composition significantly alter the nanostructures of the C-S-H-type and N-A-S-H-type gels. Mean SiIV–O–AlIV bond angles for each type of AlIV site environment are highly consistent, with compositional changes dictating the relative proportions of individual AlIV species but not altering the local structure of each AlIV site. These findings reveal the molecular interactions governing the (calcium,alkali)-aluminosilicate gel nanostructure, which are crucial in controlling material properties and durability

Can Surgical Trainees Achieve Arthroscopic Competence at the End of Training Programs? A Cross-sectional Study Highlighting the Impact of Working Time Directives.

PURPOSE: To provide training guidance on procedure numbers by assessing how the number of previously performed arthroscopic procedures relate to both competent and expert performance in simulated arthroscopic shoulder tasks. METHODS: A cross-sectional study that assessed simulated shoulder arthroscopic performance was undertaken. A total of 45 participants of varying experience performed 2 validated tasks: a simple diagnostic task and a more complex Bankart labral repair task. All participants provided logbook numbers for previously performed arthroscopies. Performance was assessed with the Global Rating Scale and motion analysis. Receiver operating characteristic curve analyses were conducted to identify optimum cut points for task proficiency at both "competent" and "expert" levels. RESULTS: Increasing surgical experience resulted in significantly better performance for both tasks as assessed by Global Rating Scale or motion analysis (P < .0001). Receiver operating characteristic curve analyses demonstrated 52 previous arthroscopies were needed to perform to a competent level at the diagnostic task and 248 to be competent at the complex task. To perform at an expert level, 290 and 476 previous arthroscopies, respectively, were needed. CONCLUSIONS: This study provides quantified guidance for arthroscopic training and highlights the positive relationship between arthroscopic case load and arthroscopic competency. We have estimated that the number of arthroscopies required to achieve competency in a basic arthroscopic task exceed those recommended in some countries. These estimates provide useful guidance to those responsible for training program. CLINICAL RELEVANCE: The numbers to achieve competent arthroscopic performance in the assessed simulated tasks exceed what is recommended and what is possible during surgical training programs in some countries

Serum glial fibrillary acidic protein: a neuromyelitis optica spectrum disorder biomarker

OBJECTIVE: Blood tests to monitor disease activity, attack severity, or treatment impact in neuromyelitis optica spectrum disorder (NMOSD) have not been developed. This study investigated the relationship between serum glial fibrillary acidic protein (sGFAP) concentration and NMOSD activity and assessed the impact of inebilizumab treatment. METHODS: N-MOmentum was a prospective, multicenter, double-blind, placebo-controlled, randomized clinical trial in adults with NMOSD. sGFAP levels were measured by single-molecule arrays (SIMOA) in 1,260 serial and attack-related samples from 215 N-MOmentum participants (92% aquaporin 4-immunoglobulin G-seropositive) and in control samples (from healthy donors and patients with relapsing-remitting multiple sclerosis). RESULTS: At baseline, 62 participants (29%) exhibited high sGFAP concentrations (≥170 pg/ml; ≥2 standard deviations above healthy donor mean concentration) and were more likely to experience an adjudicated attack than participants with lower baseline concentrations (hazard ratio [95% confidence interval], 3.09 [1.6-6.1], p = 0.001). Median (interquartile range [IQR]) concentrations increased within 1 week of an attack (baseline: 168.4, IQR = 128.9-449.7 pg/ml; attack: 2,160.1, IQR = 302.7-9,455.0 pg/ml, p = 0.0015) and correlated with attack severity (median fold change from baseline [FC], minor attacks: 1.06, IQR = 0.9-7.4; major attacks: 34.32, IQR = 8.7-107.5, p = 0.023). This attack-related increase in sGFAP occurred primarily in placebo-treated participants (FC: 20.2, IQR = 4.4-98.3, p = 0.001) and was not observed in inebilizumab-treated participants (FC: 1.1, IQR = 0.8-24.6, p > 0.05). Five participants (28%) with elevated baseline sGFAP reported neurological symptoms leading to nonadjudicated attack assessments. INTERPRETATION: Serum GFAP may serve as a biomarker of NMOSD activity, attack risk, and treatment effects. ANN NEUROL 2021;89:895-910

ICON 2019: International Scientific Tendinopathy Symposium Consensus: Clinical Terminology

© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.Background Persistent tendon pain that impairs function has inconsistent medical terms that can influence choice of treatment.1 When a person is told they have tendinopathy by clinician A or tendinitis by clinician B, they might feel confused or be alarmed at receiving what they might perceive as two different diagnoses. This may lead to loss of confidence in their health professional and likely adds to uncertainty if they were to search for information about their condition. Clear and uniform terminology also assists inter-professional communication. Inconsistency in terminology for painful tendon disorders is a problem at numerous anatomical sites. Historically, the term ‘tendinitis’ was first used to describe tendon pain, thickening and impaired function (online supplementary figure S1). The term ‘tendinosis’ has also been used in a small number of publications, some of which were very influential.2 3 Subsequently, ‘tendinopathy’ emerged as the most common term for persistent tendon pain.4 5 To our knowledge, experts (clinicians and researchers) or patients have never engaged in a formal process to discuss the terminology we use. We believe that health professionals have not yet agreed on the appropriate terminology for painful tendon conditions.Peer reviewedFinal Accepted Versio

Beyond energy efficiency in evaluating sustainable development in planning and the built environment

The EU has set the policy target of reducing energy use by 20% by the year 2020. Therefore, a substantial consumption decrease is needed in the built environment sector. Despite the great energy efficiency improvements in households, recent energy consumption data analyses show that these targets will unlikely be reached. The general aim of this study is to point out the need to define new indicators and evaluation approaches in urban planning and the built environment which are based on the concept of ‘energy subsidiarity', focusing on local renewable resources rather than on current approaches based on energy efficiency. This concept correlates energy consumption with the energy supply from local renewable resources and is here proposed as the new urban planning evaluation approach toward a sustainable built environment. In the paper, the ‘Jevons Paradox' concept and the ‘energy rebound effect' phenomenon are used to demonstrate how current approaches based on energy efficiency, alone, cannot lead to a remarkable reduction of energy consumption. This is also supported by data on European energy consumption and European energy efficiency in the built environment. Finally, a number of well-known European ecological districts (‘eco-districts') are analysed in terms of sustainable energy strategy as well as energy efficiency and energy balance. This study shows that there is a contradiction between the purpose of some of the eco-districts to be low consumption (or low impacts), and the district renewable energy balance. Only a few of the analysed eco-districts are able to cover energy needs by using renewable energy obtained in the surrounding area. In most of the cases, the focus of the districts' activities is on energy efficiency. According to the ‘Jevons Paradox' and ‘energy rebound effect' paradigm, energy efficiency alone will unlikely lead to an effective reduction in resources' consumption. These results point out the need for a radical shift toward the development of new approaches in the assessment and management of the built environment for sustainabilit

Agro-materials : a bibliographic review

Facing the problems of plastic recycling and fossil resources exhaustion, the use of biomass to conceive new materials appears like a reasonable solution. Two axes of research are nowadays developed : on the one hand the synthesis of biodegradable plastics, whichever the methods may be, on the other hand the utilization of raw biopolymers, which is the object of this paper. From this perspective, the “plastic” properties of natural polymers, the caracteristics of the different classes of polymers, the use of charge in vegetable matrix and the possible means of improving the durability of these agro-materials are reviewed

Turbulence induced additional deceleration in relativistic shock wave propagation: implications for gamma-ray burst

The late afterglow of gamma-ray burst is believed to be due to progressive deceleration of the forward shock wave driven by the gamma-ray burst ejecta propagating in the interstellar medium. We study the dynamic effect of interstellar turbulence on shock wave propagation. It is shown that the shock wave decelerates more quickly than previously assumed without the turbulence. As an observational consequence, an earlier jet break will appear in the light curve of the forward shock wave. The scatter of the jet-corrected energy release for gamma-ray burst, inferred from the jet-break, may be partly due to the physical uncertainties in the turbulence/shock wave interaction. This uncertainties also exist in two shell collisions in the well-known internal shock model proposed for gamma-ray burst prompt emission. The large scatters of known luminosity relations of gamma-ray burst may be intrinsic and thus gamma-ray burst is not a good standard candle. We also discuss the other implications.Comment: accepted for publication in Astrophysics and Space Scienc

A study of the appearance of tau neutrinos from a gamma ray burst by detecting their horizontal electromagnetic showers

We explore the possibilty of detecting horizontal electromagnetic showers of tau neutrinos from individual gamma ray bursts, in large scale detectors like HiRes and Telescope Array. We study the role of the parameters of a gamma ray burst in determining the expected number of tau events from that burst. The horizontal beam of tau leptons produce visible signals in the atmosphere. We find that there is a slim chance of observing tau lepton appearances from GRBs with Telescope Array. The number of signals is strongly dependent on the Lorentz factor $\Gamma$, redshift $z$ of a GRB, energy emitted in muon neutrinos and antineutrinos $E_{\nu,HE}$ and also on some other parameters of a GRB. It is possible to understand neutrino oscillations in astrophysical neutrinos and the mechanism or model of neutrino production inside a GRB by detection or non detection of tau lepton signals from it.Comment: 22 pages, 7 figures, minor changes made in the tex