Oblique Photogrammetric Analysis of Dome Growth at Mount St. Helens Volcano, 2004 – 2007

This project is an oblique photogrammetric survey of the 2004-2007 dome-building eruption of Mount St. Helens volcano with two primary objectives: (1) to evaluate the potential of a new rapid and low-cost technique to create digital elevation models (DEMs) and subsequently calculate dome volumes and extrusion rates at Mount St. Helens; and (2) to attempt to understand mechanics associated with lava dome extrusion and collapse by analyzing volumetric and extrusion rate measurements in the context of dome height measurements, seismicity data, and migration of the locus of dome growth. The new method uses sets of oblique aerial photographs, acquired from a helicopter with a standard digital camera, and commercially available photogrammetry software to create DEMs. Twelve sets of overlapping digital images from November 2004 to April 2007 of the growing dome inside the crater of Mount St. Helens were used to produce DEMs. Analyses of the digital images were carried out using PhotoModeler software, which produces three dimensional coordinates of points identified in multiple photos. The DEMs were used for qualitative and quantitative descriptions of the 2004-2007 eruption. The DEMs were used to calculate height, volume, and extrusion rate, and to track changes in these quantities through time. These quantities show a decreasing extrusion rate through time that has remained lower than 1 m3/s since October 2005. Total dome volume had reached 94x106 m3 as of April 2007, a larger volume than that of the 1980-1986 Dome. Quantitative evaluation of the DEMs also shows a relationship between dome height and extrusion rate, which varies with the character of eruptive activity. Results were validated by comparing volume measurements derived from traditional aerophotogrammetric surveys run by the USGS Cascades Volcano Observatory. The new oblique photogrammetric technique yields estimates of eruptive volume consistently within 5% of the volumes estimated with traditional surveys. The end result of this project is a new technique that provides inexpensive, rapid assessment of volcanic activity that can be an important supplement to volcano monitoring worldwide

The phenotype and genotype of adult obstructive sleep apnoea/hypopnoea syndrome

To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldObstructive sleep apnoea/hypopnoea syndrome (OSAHS) is a common condition affecting approximately 2-4% of the middle-aged population. A hereditary component to the condition has long been recognised but its genetic basis has been difficult to elucidate. Progress in determining the genotype of OSAHS is hampered by the lack of a consistent definition of phenotype and the large environmental influences on its expression. "Intermediate phenotypes", such as craniofacial structure, obesity and upper airway control, have been utilised. Multiple gene polymorphisms have been explored in association with the latter, as well as with the sequelae of OSAHS, such as hypertension and increased insulin resistance. To date, two genome-wide scans have identified potential regions that may be of interest in further defining the intermediate phenotypes. The present paper focuses on human studies with an update of the most recent work in the area, including a short discussion on methods of genetic studies

Twenty years of explosive-effusive activity at El Reventador volcano (Ecuador) recorded in its geomorphology

Shifts in activity at long-active, open-vent volcanoes are difficult to forecast because precursory signals are enigmatic and can be lost in and amongst daily activity. Here, we propose that crater and vent morphologies, along with summit height, can help us bring some insights into future activity at one of Ecuador’s most active volcanoes El Reventador. On 3 November 2002, El Reventador volcano experienced the largest eruption in Ecuador in the last 140 years and has been continuously active ever since with transitions between and coexistence of explosive and effusive activity, characterized by Strombolian and Vulcanian behavior. Based on the analysis of a large dataset of thermal and visual images, we determined that in the last 20 years of activity, the volcano faced three destructive events: A. Destruction of the upper part of the summit leaving a north-south breached crater (3 November 2002), B. NE border crater collapse (2017), and C. NW flank collapse (2018), with two periods of reconstruction of the edifice: Period 1. Refill of the crater (2002-early 2018) and Period 2. Refill of the 2018 scar (April 2018–December 2022). Through photogrammetric analysis of visual and thermal images acquired in 11 overflights of the volcano, we created a time-series of digital elevation models (DEMs) to determine the maximum height of the volcano at each date, quantify the volume changes between successive dates, and characterize the morphological changes in the summit region. We estimate that approximately 34.1x10⁶ m³ of volcanic material was removed from the volcano due to destructive events, whereas 64.1x10⁶ m³ was added by constructive processes. The pre-2002 summit height was 3,560 m and due to the 2002 eruption it decreased to 3,527 m; it regained its previous height between 2014 and 2015 and the summit crater was completely filled by early April 2018. Event A resulted from an intrusion of magma that erupted violently; we proposed that Events B and C could be a result of an intrusion as well but may also be due to a lack of stability of the volcano summit which occurs when it reaches its maximum height of approximately 3,590 and 3,600 m

THE ROLE OF DENTISTRY IN FEDERAL-STATE-LOCAL COMPREHENSIVE HEALTH PLANNING *

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65702/1/j.1752-7325.1968.tb01419.x.pd

Computerized cognitive training in prostate cancer patients on androgen deprivation therapy: a pilot study

© 2017, Springer-Verlag GmbH Germany, part of Springer Nature. Purpose: Prostate cancer patients who have undergone androgen deprivation therapy (ADT) may experience cognitive impairment, yet there is an unmet need for nonpharmacological interventions to address cognitive impairment in this population. This study examines the feasibility, acceptability, and preliminary efficacy of a home-based computerized cognitive training (CCT) program to treat cancer-related cognitive impairment. Methods: Sixty men who had received ≥ 3 months of ADT were screened for at least mild cognitive or neurobehavioral impairment and randomized to 8 weeks of CCT or usual care. Follow-up assessments occurred immediately post-intervention or equivalent (T2) and 8 weeks later (T3). The acceptability of CCT was also assessed. Results: Feasibility:A priori feasibility thresholds were partially met (i.e., randomization rate \u3e 50%, retention rate \u3e 70% excluding CCT drop-outs, but \u3c 70% for intent-to-treat). Acceptability: Participants were mostly satisfied with CCT and found it somewhat enjoyable, though barriers to uptake existed. Preliminary efficacy: Linear mixed models indicated significant time by group effects favorable to CCT in reaction time (p =.01), but unfavorable to CCT in verbal and visual memory (ps \u3c .05). Memory was temporarily suppressed in the CCT group at T2, but normalized by T3. There was no effect of CCT on self-reported cognitive functioning, neurobehavioral functioning, nor quality of life. Conclusions: This study provides tentative support for the feasibility and acceptability of CCT to treat mild cognitive impairment in ADT patients. CCT had a beneficial effect on reaction time, but temporarily suppressed memory. CCT’s benefits may be limited to a narrow area of functioning. Larger-scale studies are needed