A geoneutrino experiment at Homestake

A significant fraction of the 44TW of heat dissipation from the Earth's interior is believed to originate from the decays of terrestrial uranium and thorium. The only estimates of this radiogenic heat, which is the driving force for mantle convection, come from Earth models based on meteorites, and have large systematic errors. The detection of electron antineutrinos produced by these uranium and thorium decays would allow a more direct measure of the total uranium and thorium content, and hence radiogenic heat production in the Earth. We discuss the prospect of building an electron antineutrino detector approximately 700m^3 in size in the Homestake mine at the 4850' level. This would allow us to make a measurement of the total uranium and thorium content with a statistical error less than the systematic error from our current knowledge of neutrino oscillation parameters. It would also allow us to test the hypothesis of a naturally occurring nuclear reactor at the center of the Earth.Comment: proceedings for Neutrino Sciences 2005, submitted to Earth, Moon, and Planet

Static deformations and gravity changes at the Earth's surface due to atmospheric loading

Deformations and gravity changes at the Earth's surface due to regional and global air pressure variations are estimated for a radially stratified Earth. The results are as follows:- Vertical displacements of seasonal character have maximum amplitudes of ±0.5 cm. (Anti-)Cyclones can cause vertical displacements of up to ±2.5 cm.- Horizontal displacements have amplitudes less than ±2.5 mm.- Horizontal principal strains may have amplitudes up to 10-8. They reduce to about ±1.5✻10-9 for seasonal changes in the air pressure distribution.- The total gravity perturbation consisting of the Newtonian attraction of air masses and of self-gravitation due to the elastic deformation may go up to ±20 μgal in the case of (anti-)cyclones, and ±3 μgal in the case of seasonal air pressure changes.- The total tilt due to seasonal air pressure variations can be as high as ±1.5 mseca. For passing (anti-)cyclones this value may go up to ±10 mseca. All the above values have to be modified in the direct vicinity of coastlines. The modification is only slight for the displacements and the secondary gravity effect, but it is important for the other components. There, the necessary modification may amount to several hundred percent depending on the type of deformation component and on the distance to the coastline. Precise air pressure corrections of radial displacements and gravity changes cannot be achieved by using a single regression coefficient. Either the characteristic wavelengths of the pressure distribution have to be taken into account or the following two-coefficient correction equations have to be used:   Radial displacement:      u  = -0.90 p̂ - 0.35 (p - p̂ )  Primary gravity:               gp =  0.36 p̄ + 0.41 (p - p̄ )  Secondary gravity:          gs = -0,17 p̂ - 0.08 (p - p̂ )  Total gravity:                    g  =  gp + gswith u = radial displacement in mm, gp, gs, g = primary, secondary and total gravity, respectively, in μgal, p = local pressure variation in mbar, p̄ = average of the pressure variation in a surrounding area of 2,000 km (in mbar) and p̂   the same average, except for setting the pressure values equal to zero over ocean areas. These corrections have been tested for seasonal air pressure variations and they have proved to be highly precise. The average errors are less than 0.5 mm, 0.1 μgal, 0.1 μgal and 0.2 μgal for the radial displacements, the primary, secondary and total gravity changes, respectively. The maximum errors are less than 1 mm in the case of the radial displacements, 0.3 μgal and 0.2 μgal for the primary and secondary gravity changes, respectively, and 0.4 μgal for the total gravity changes. Due to a small, spatially constant error term these values apply strictly only to spatial differences of the above deformation components. The differences, however, can be taken between any two points on the Earth's surface.           ARK: https://n2t.net/ark:/88439/y011765 Permalink: https://geophysicsjournal.com/article/150 &nbsp

T2015 Multivariate Analysis of Predictors for Severity of Mucosal Lesions in Patients with GERD Symptoms (Mapsomal): A Clinical, Epidemiological and Endoscopic Survey

Background: Improvement of symptoms plays a critical role for assessment of treatment outcome in patients with gastroesophageal reflux disease (GERD). Interestingly, most data on long-term outcome of these patients come from clinical trials that assessed the response to treatment in highly standardized trial conditions, with very strict entry criteria and frequent follow-up visits, that are unlikely to be representative of outcomes in standard clinical settings. AIM: To assess the long-term outcome of patients presenting with GERD symptoms for diagnostic work-up in a usual clinical care setting and the clinical predictors of response/ non-response. This abstract summarizes the interim analysis after recruitment of 100 patients. Methods: One hundred patients referred for endoscopic assessment of suspected GERD within a single metropolitan area health service were recruited; 82 consecutive patients from the Royal Adelaide Hospital (RAH) and 28 from the Lyell McEwen Health Centre (LMH). Symptoms and psychological co-morbidities were assessed utilizing the Bowel Disease Ques- tionnaire, the Hospital Anxiety and Depression Scale and the Nepean Dyspepsia Index. Questionnaires were mailed to the patients. Data on endoscopic findings at referral using the Los Angeles (LA) classification were included. As this was an observational study, routine clinical management by the referring GP was not altered. RESULTS: 68 patients were on proton pump inhibitor (PPI) therapy while 31 patients did not receive the treatment. In 58 patients endoscopy revealed no visible esophagitis. The frequency of heartburn was signific- antly associated with the presence of hiatal hernia but the frequency of reflux symptoms was not linked to the presence or severity of endoscopic lesions. Follow-up data > 2 month were available for 38 patients. Out of these 86.8% continued to have heartburn and 76.3% an acid taste after more than 2 months of treatment. The symptomatic response to PPI was significantly better (p0.05). 36% of patients reported a history of anxiety and depression but these disorders were not correlated with symptom frequency or response to PPI therapy. Conclusions: a) Frequency of GERD symptoms is not associated with severity of mucosal lesions; b) presence of a hiatal hernia is linked to more frequent symptoms; c) presence of a hiatal hernia predicts a favourable response to PPI therapy.Nora B. Zschau, William Tam, Jane M. Andrews, Richard H. Holloway, Mark Schoeman, Gerald J. Holtman

Gastroesophageal reflux disease after diagnostic endoscopy in the clinical setting

AIM: To investigate the outcome of patients with symptoms of gastroesophageal reflux disease (GERD) referred for endoscopy at 2 and 6 mo post endoscopy. METHODS: Consecutive patients referred for upper endoscopy for assessment of GERD symptoms at two large metropolitan hospitals were invited to participate in a 6-mo non-interventional (observational) study. The two institutions are situated in geographically and socially disparate areas. Data collection was by self-completion of questionnaires including the patient assessment of upper gastrointestinal disorders symptoms severity and from hospital records. Endoscopic finding using the Los-Angeles classification, symptom severity and it’s clinically relevant improvement as change of at least 25%, therapy and socio-demographic factors were assessed. RESULTS: Baseline data were available for 266 patients and 2-mo and 6-mo follow-up data for 128 and 108 patients respectively. At baseline, 128 patients had erosive and 138 non-erosive reflux disease. Allmost all patient had proton pump inhibitor (PPI) therapy in the past. Overall, patients with non-erosive GERD at the index endoscopy had significantly more severe symptoms as compared to patients with erosive or even complicated GERD while there was no difference with regard to medication. After 2 and 6 mo there was a small, but statistically significant improvement in symptom severity (7.02 ± 5.5 vs 5.9 ± 5.4 and 5.5 ± 5.4 respectively); however, the majority of patients continued to have symptoms (i.e., after 6 mo 81% with GERD symptoms). Advantaged socioeconomic status as well as being unemployed was associated with greater improvement. CONCLUSION: The majority of GORD patients receive PPI therapy before being referred for endoscopy even though many have symptoms that do not sufficiently respond to PPI therapy.Nora B Zschau, Jane M Andrews, Richard H Holloway, Mark N Schoeman, Kylie Lange, William CE Tam, Gerald J Holtman

Reply to "Comment on 'Operational Earthquake Forecasting: Status of Knowledge and Guidelines for Implementation by Jordan et al. [2011]' by Stuart Crampin"

In his commentary on the International Commission on Earthquake Forecasting (ICEF) report [Jordan et al. 2011], Crampin [2012] claims that observable changes in shear-wave splitting can predict large earthquakes on short time scales with high reliability and skill, and he challenges a central ICEF finding—that no method has yet demonstrated such a predictive capability. In particular, Crampin asserts that "observations of seismic shear-wave splitting monitored at a three-borehole Stress-Monitoring Site (SMS) in central Italy could monitor stress-accumulation and stress-relaxation (crack-coalescence) before all damaging (M ≥ 5) earthquakes within 1000 km of the SMS […] This means that installation of one expensive SMS (preferably two throughout the length of Italy) would stress-forecast the time, magnitude, and in some circumstances fault-break of all potentially damaging on the mainland of Italy".<br />Crampin's assertions are based on prediction methods he has advocated for several decades [e.g., Crampin et al. 1984; Crampin et al. 1990]. As part of the ICEF study, we reviewed the literature on these methods. Nothing contained in the present commentary compels us to alter our previous findings. [...]<br /&gt