An Investigation into the Effects of Classroom Acoustics on Teachers’ Voices

The acoustic design of classrooms has traditionally focused on pupils hearing the teacher. There is a need for guidance on the consideration of voice ergonomics for teachers in classroom design. This project undertook measurements of teachers’ voices in classrooms with different acoustic properties to examine possible relationships between voice parameters and classroom acoustics. The mean voice level measured was classified as ‘loud’ (based on guidance values) and the participants spoke for a large proportion of the day (average 21%). Those teaching in rooms with higher unoccupied noise levels spoke with a higher sound level. There was a significant, moderate, positive correlation between voice levels in female participants and the unoccupied noise levels in the same region of the noise spectrum as the fundamental frequency of the female voice. There were signs of a similar relationship for male participants. This indicated that the control of low frequency noise levels and reverberation times (not currently covered by schools guidance documents in England) may be important in reducing voice levels and the associated vocal risks. An online survey was also undertaken which gathered 153 responses and included questions on voice problems, voice training, classroom acoustics and general health. The respondents reported a number of interesting findings. 66% reported having experienced voice problems, with many continuing to work despite these problems. A relatively small proportion of respondents had received voice training (41%), and many reported shouting or raising their voice. There were greater rates of reported voice problems in teachers of young children and those teaching in open plan classrooms. Subjectively the main acoustic issues for teachers were inadequate internal sound insulation and excessive reverberation. External noise intrusion was not reported as significant

Surface Subsidence Over Deep Solution Mined Storage Cavern Field

Ten years observation by GDF on Tersanne solution-mined gas storage field, offers the opportunity for a mechanical interpretation of the surface subsidence. According to the geological context, the rockmass was modellised by a two-layered medium with highly contrasted mechanical behavior: a soft elastic clay cover, and a viscous salt mass. Given the field uncertainties, mostly related to the cover layer, and the three- dimensional nature of the problem, indirect methods were used to obtain bounds for the surface subsidence evolution and a parametric study was performed. Comparison with data of the field allows to determine likely rock mass parameters, put forward some typical mechanical response, and give some insight on the trends of the subsidence phenomena

Collisional kinetics of non-uniform electric field, low-pressure, direct-current discharges in H2_{2}

A model of the collisional kinetics of energetic hydrogen atoms, molecules, and ions in pure H$_2$ discharges is used to predict H$_\alpha$ emission profiles and spatial distributions of emission from the cathode regions of low-pressure, weakly-ionized discharges for comparison with a wide variety of experiments. Positive and negative ion energy distributions are also predicted. The model developed for spatially uniform electric fields and current densities less than $10^{-3}$ A/m$^2$ is extended to non-uniform electric fields, current densities of $10^{3}$ A/m$^2$, and electric field to gas density ratios $E/N = 1.3$ MTd at 0.002 to 5 Torr pressure. (1 Td = $10^{-21}$ V m$^2$ and 1 Torr = 133 Pa) The observed far-wing Doppler broadening and spatial distribution of the H$_\alpha$ emission is consistent with reactions among H$^+$, H$_2^+$, H$_3^+$, and H$^-H$ ions, fast H atoms, and fast H$_2$ molecules, and with reflection, excitation, and attachment to fast H atoms at surfaces. The H$_\alpha$ excitation and H$^-$ formation occur principally by collisions of fast H, fast H$_2$, and H$^+$ with H$_2$. Simplifications include using a one-dimensional geometry, a multi-beam transport model, and the average cathode-fall electric field. The H$_\alpha$ emission is linear with current density over eight orders of magnitude. The calculated ion energy distributions agree satisfactorily with experiment for H$_2^+$ and H$_3^+$, but are only in qualitative agreement for H$^+$ and H$^-$. The experiments successfully modeled range from short-gap, parallel-plane glow discharges to beam-like, electrostatic-confinement discharges.Comment: Submitted to Plasmas Sources Science and Technology 8/18/201

Treatment of newly-diagnosed gastroesophageal reflux disease: a nationwide register-based cohort study

Objective: The aim of this study was to describe short-term treatment of gastroesophageal reflux disease (GERD) in patients registered with a GERD-diagnosis as part of evaluation with endoscopy using national Danish registers. Methods: The study population included all adults undergoing upper gastrointestinal endoscopy in Denmark from 1 January 2000 to 31 December 2015, who within 90 days received a diagnosis of GERD. We obtained nationwide data from The National Patient Registry on procedures (endoscopy and anti-reflux surgery) and diagnosis (GERD diagnosis and comorbidity), The Danish National Prescription Registry on the use of anti-reflux medication and ulcerogenic drugs, and The National Civil Registry on death and civil status. The primary outcome was a type of treatment of GERD within two years of primary endoscopy defined as either no treatment, medical treatment alone, surgical treatment alone or both medical and surgical treatment. Results: A total of 36,292 patients were included in the study. Endoscopies were performed without biopsies in 67.5% (n = 24,479) of cases. The majority (66.3%, n = 24,077) was registered as GERD with esophagitis. After initial endoscopy, 10.6% (n = 3862) received no pharmacological or surgical treatment for GERD within two years of follow-up, 87.5% (n = 31,761) received only pharmacological treatment, 0.1% (n = 50) received only surgical treatment and 1.7% (n = 619) received a combination of pharmacological and surgical treatment. Conclusion: Patients referred to investigation with endoscopy and diagnosed with GERD in Denmark are primarily treated with pharmacological anti-reflux treatment within the first two years with PPI being the primary agent. Only a small fraction of patients is treated surgically.</p

Long-term patient satisfaction and durability of laparoscopic anti-reflux surgery in a large Danish cohort: study protocol for a retrospective cohort study with development of a novel scoring system for patient selection

INTRODUCTION: Laparoscopic anti-reflux surgery is standard of care in surgical treatment of gastro-oesophageal reflux disease and is not without risks of adverse effects, including disruption of the fundoplication and postfundoplication dysphagia, in some cases leading to reoperation. Non-surgical factors such as pre-existing anxiety or depression influence postoperative satisfaction and symptom relief. Previous studies have focused on a short-term follow-up or only certain aspects of disease, such as reoperation or postoperative quality of life. The aim of this study is to evaluate long-term patient-satisfaction and durability of laparoscopic anti-reflux surgery in a large Danish cohort using a comprehensive multimodal follow-up, and to develop a clinically applicable scoring system usable in selecting patients for anti-reflux surgery.METHODS AND ANALYSIS: The study is a retrospective cohort study utilising data from patient records and follow-up with patient-reported quality of life as well as registry-based data. The study population consists of all adult patients having undergone laparoscopic anti-reflux surgery at The Department of Surgery, Kolding Hospital, a part of Lillebaelt Hospital Denmark in an 11-year period. From electronic records; patient characteristics, preoperative endoscopic findings, reflux disease characteristics and details on type of surgery, will be identified. Disease-specific quality of life and dysphagia will be collected from a patient-reported follow-up. From Danish national registries, data on comorbidity, reoperative surgery, use of pharmacological anti-reflux treatment, mortality and socioeconomic factors will be included. Primary outcome of this study is treatment success at follow-up.ETHICS AND DISSEMINATION: Study approval has been obtained from The Danish Patient Safety Agency, The Danish Health Data Authority and Statistics Denmark, complying to Danish and EU legislation. Inclusion in the study will require informed consent from participating subjects. The results of the study will be published in peer-reviewed medical journals regardless of whether these are positive, negative or inconclusive.TRIAL REGISTRATION NUMBER: Clinicaltrials.gov (NCT03959020).</p

Recurrence of a hiatal hernia with intrathoracic perforation and respiratory failure during pregnancy

Recurring diaphragmatic hernias severely complicating pregnancy is a rare but potentially fatal condition. Varying symptoms and low incidence often lead to delays in diagnosis and treatment, causing increased morbidity and mortality. We present a case where a 31-year-old pregnant woman developed respiratory failure due to a right mediastinal shift caused by perforation of an incarcerated hiatal hernia, for which she had previously been operated for. Post-operatively, she suffered from vomiting due to gastroparesis, likely caused by damage to the vagus nerve, and needed supplementary nutrition

Trends of anti-reflux surgery in Denmark 2000–2017:a nationwide registry-based cohort study

Background: The utilisation of laparoscopic fundoplication peaked internationally around 2000. Perioperative morbidity, mortality, and length of stay initially declined as the use of laparoscopic technique increased. Studies indicate that complication rates have increased over time, probably as a consequence of rising age and level of comorbidity. None of these previous studies is nationwide. Therefore, this study aimed to investigate trends in the utilisation of anti-reflux surgery in the entire Danish population from 2000 to 2017. Methods: Nationwide Danish health registries were utilised to include all Danish patients undergoing anti-reflux surgery 2000–2017. The utilisation of anti-reflux surgery in procedures per 100.000 inhabitants was compared to the utilisation of proton-pump inhibitors for each year. Postoperative complications, mortality, and length of stay per year, including yearly changes, were also calculated. Results: The use of anti-reflux surgery peaked in 2001 with 5.9 procedures per 100,000 inhabitants and reached its lowest point in 2008 with 2.8 procedures per 100,000 inhabitants. The use of proton-pump inhibitors increased from 3,370 users per 100,000 inhabitants in 2000 to 10,284 users per 100,000 inhabitants in 2017. The 30-day and 90-day mortality ranged from 0 to 1.2%. The 30-day hospital-registered complications were 1.3–6.1%, and the 90-day hospital-registered complications were 2.4–8.3%. Length of stay was consistently low, with a median of 2 days in 2000 reduced to a median of 1 day by 2017. Conclusion: The utilisation of anti-reflux surgery in Denmark from 2000 to 2017 declined, and the use of PPI increased dramatically. Age, comorbidity, and postoperative complications increased, while the use of laparoscopic technique remained high, and mortality was consistently low.</p

Reoperation after antireflux surgery:a population-based cohort study

Background: Antireflux surgery for gastro-oesophageal reflux disease (GORD) and/or hiatal hernia is effective. Between 10 and 20 per cent of patients undergo reoperation for recurrent symptoms. Most studies are undertaken in a single centre and possibly underestimate the rate of reoperation. The aim of this nationwide population-based cohort study was to investigate long-term reoperation rates after antireflux surgery. Methods: This study included patients who underwent antireflux surgery between 2000 and 2017 in Denmark, and were registered in the Danish nationwide health registries. Reoperation rates were calculated for 1, 5, 10 and 15 years after the primary antireflux operation for GORD and/or hiatal hernia. Duration of hospital stay, 30- and 90-day mortality and morbidity, and use of endoscopic pneumatic dilatation were assessed. Results: This study included a total of 4258 antireflux procedures performed in 3717 patients. Some 3252 patients had only primary antireflux surgery and 465 patients underwent reoperation. The 1-, 5-, 10- and 15-year rates of repeat antireflux surgery were 3·1, 9·3, 11·7 and 12·8 per cent respectively. Thirty- and 90-day mortality rates were similar for primary surgery (0·4 and 0·6 per cent respectively) and reoperations. The complication rate was higher for repeat antireflux surgery (7·0 and 8·3 per cent at 30 and 90 days respectively) than primary operation (3·4 and 4·8 per cent). A total of 391 patients (10·5 per cent of all patients) underwent endoscopic dilatation after primary antireflux surgery, of whom 95 (24·3 per cent) had repeat antireflux surgery. Conclusion: In this population-based study in Denmark, the reoperation rate 15 years after antireflux surgery was 12·8 per cent. Reoperations were associated with more complications.</p

Does consciousness exist independently of present time and present time independently of consciousness

International audienceWhile some are currently debating whether time may or may not be an illusion, others keep devoting their time to the science of consciousness. Time as such may be seen as a physical or a subjective variable, and the limitations in our capacity of perceiving and analyzing temporal order and change in physical events definitely constrain our understanding of consciousness which, in return, constrains our conceptual under-standing of time. Temporal codes generated in the brain have been considered as the key to insight into neural function and, ultimately, as potential neural substrates of consciousness itself. On the basis of cur-rent evidence and opinion from neuroscience and philosophy, we consider the interrelation between con-sciousness and time in the light of Hegel and Heidegger's concepts of Sein (Being) and Zeit (Time). We suggest that consciousness can be defined in terms of a succession of psychological moments where we realize that we exist in, and are part of, a present moment in time. This definition places all other percep-tual or sensorial processes which may characterize phenomenal experience at a different level of analysis and centers the debate around consciousness on the fundamental identity link between awareness of the Ich (I) and awareness of what Heidegger termed Ursprüngliche Zeit (original time). We argue that human consciousness has evolved from the ability to be aware of, to remember, and to predict temporal order and change in nature, and that the limits of this capacity are determined by limits in the functional plasticity of resonant brain mechanisms. Although the conscious state of the Self is the ultimate expression of this evolution, it is devoid of any adaptive function as such

Une mesure de la perméabilité et du fluage d'une caverne dans le sel

Rock mass properties diff er significanùy from those measured on sam pies in the laboratory. A test has been performed on a deep brine-fi.lled ca vern, with the objective of measuring the equilibrium pressure reached when the ca vern was closed. Such an equilibrium is reached when salt mass creep, which leads to cavern shrinkage, balances brine permeation through the ca vern wall. A K = 2·10-19 m 2 value of the average in situ intrinsic permeability has been deduced from the test; it is significantly higher than the intrinsic permeability measured in a weil or in the laboratory. This result supports ca vern abandonment scenarios in which the risk of natural fracturation due to high brine pressures is alleviated.Les propriétés d'un massif rocheux sont en général différentes de celles mesurées au laboratoire sur un échantillon. On a cherché la pression d'équilibre à laquelle se stabilise la saumure contenue dans une cavité souterraine profonde fermée. Cet équilibre résulte de l'action du fluage du massif, qui tend à refermer la cavité, et de la perméation de la saumure à travers les parois de la cavité. On déduit de la valeur d'équilibre mesurée une perméabilité intrinsèque moyenne de l'ordre de $K = 2·10^{-19}\text{m}^2$, sensiblement plus forte que les valeurs estimées antérieurement sur des échantillons ou dans un puits. Ce résultat permet de construire un scénario du comportement de la caverne après abandon, qui exclut le risque de fracturation naturelle