Physical Description and Significance of the Tills at the Dobmeier Pit Near Park River, North Dakota

This study was conducted to describe an exposure of tills and correlate them with the known sequence of tills elsewhere. The Dobmeier pit is a large spring discharge site approximately 3 miles west of Park River, North Dakota (Edinburg Quadrangle, T157N, R56W, Sec. 23, 1/4SE, 1/4NW, 1/4SE). It is between 50 and 75 meters across and 15 to 20 meters deep. It is located on the east edge of the Edinburg Moraine and the south side of the Park River valley. Exposed at the base is a cross-bedded sand and gravel unit. Above is a compact gray till, which is separated by a relatively thin, discontinuous sand lens. Overlying the gray till is a much less compact, yellow brown till. Above the upper till are lenses of cross-bedded sand then a tan, jointed, silty unit; above this the A and B soil horizons are developed in shaley sand and gravel. The pit walls were photographed, sketched and samples collected at 1 meter intervals in the tills and at either side of the contact of the gray and yellow-brown till. Colors of the samples were described using the Munsell Soil Color Chart. Texture was determined by the NDGS hydrometer and sieve method. The coarse sand fraction was then divided into four lithologic groups; shale, carbonate, crystalline, and other. The lower till is very dark grayish-brown to dark olive gray in color. The normalized texture is 34+5% sand, 45+5% silt, and 21+3% clay. The normalized coarse sand lithology is 51+7% shale, 24+6% carbonate, and 26+5% crystalline grains. The upper till is yellowish-brown to brownish-yellow and olive brown in color. The normalized texture is 40+20% sand, 45+21% silt, and 15+ 1% clay. The normalized coarse sand lithology is 47+7% shale, 26+6% carbonate, and 27+1% crystalline grains. The results of this analysis were compared to previous descriptions of tills of the region. The lower unit compares well with the Dahlen Formation. The till of the Dahlen Formation was deposited by a glacier that moved in from the northwest in Late Wisconsinan time, about 12,000 years BP. Stratigraphically, the upper till is most likely the Falconer Formation of which the Edinburg Moraine marks the western extent. The Falconer Formation was deposited in latest Wisconsinan time by a readvance of the same glacier that deposited the Dahlen Formation before 11,000 years BP

Glacial Chronology and Paleoclimatic Significance of Cirque Moraines near Mts Baker and Shuksan, North Cascade Range, WA

Moraines of at least two ages occur in alpine cirques near the Mt. Baker volcano in the North Cascades Range, WA. The south Swift Creek cirque preserves a distinct sequence of moraines representing the two primary age groups. In south Swift Creek cirque, the upper group of moraines (1450-1550 m) has little soil development and vegetation. Increment borings of the oldest trees growing on the upper moraines suggest that they were formed between the late 1800s and early 1900s. This age range correlates with numerous late Little Ice Age (LIA) moraines elsewhere in the Cascade Range. The south Swift Creek cirque Little Ice Age moraines have a reconstructed equilibrium line altitude (ELA) of 1550 m. The lower moraines in south Swift Creek cirque are overlain by and older than Mazama ash (6800 14C yrs B.P.). In addition, a date of 9560±50 14C yrs B.P. on charcoal from the base of a bog just outside the lowermost moraine provides a closer minimum limiting age. A date of 9350±180 14C yrs B.P. from a branch near the base of a bog behind the uppermost pre-Mazama moraine indicates that trees were growing at the edge of the cirque by that time. Other cirque moraines in Swift Creek and Shuksan Creek, which are similar in extent to the older group of south Swift Creek cirque moraines, are constrained only as older than Mazama ash. Moraines several kilometers distant and similar in altitude and geomorphic position to the pre-Mazama moraines of south Swift Creek cirque occupy the mouth of Bagley Creek cirque and dam Highwood Lake. A basal radiocarbon date from a Highwood Lake sediment core demonstrates that deglaciation occurred before 9410±50 14C yrs B.P. The similar limiting radiocarbon dates and similar reconstructed equilibrium line altitudes (ELAs) of ~ 1400 m for pre-Mazama moraines in both Bagley Creek cirque and south Swift Creek cirque indicates that they are correlative. Two dates with a mean of ~10,700 14C yrs B.P. from charcoal layers in outwash associated with moraines 40 km down the North Fork Nooksack valley provide a maximum limiting age, constraining the Swift Creek and Bagley Creek moraines to the early Holocene or late Pleistocene (Kovanen and Easterbrook, 2001). The minimum ages indicate that Bagley Creek cirque and south Swift Creek cirque moraines predate most of the early Holocene moraines on the south flank of Mt. Baker and probably correlate to the similar-scale McNeely II moraines near Mt. Rainier (Heine, 1998). However, the range of limiting dates (10,700 - 9600 14C yrs B.P.) allows an alternative correlation with the youngest Sumas moraines (younger than 10,250 14C yrs B.P.) from the remnant of the Cordilleran Ice Sheet on the Fraser Lowland (Kovanen and Easterbrook, in review-a). The modern local ELA is estimated at 1640 m from small existing glaciers at the heads of south Swift Creek cirque and Bagley Creek cirque and a regional ELA of 1890 m based on northeast-to-northwest facing, modern glaciers near the study area. The difference (ΔELA) between the modern local and the south Swift Creek Little Ice Age ELAs is 75 m. The local ELA is used because local topographic effects that strongly influence mass balance and the FT .A today probably also influenced the LIA glacier. The ΔELA between the regional ELA and the late-Pleistocene/early Holocene ELA in Swift Creek and Bagley Creek is ~ 490 m. The mean regional ELA is a more appropriate comparison for the earlier glacier positions because the glaciers were large enough at that time to have substantially reduced local topographic effects on mass balance and ELA. Simple comparisons of modem climate at reconstructed ELAs with modern glacier ELA climate conditions suggest that in order to build the oldest moraines in south Swift Creek cirque and Bagley Creek cirque, ablation season temperature would have to decrease by 1.6- degrees C or winter precipitation would have to increase by 870 mm. Similarly, building the oldest LIA moraine in south Swift Creek cirque would require a 0.85-degree C decrease in ablation season temperature or a 440-mm accumulation season precipitation increase

Can a specific neck strengthening program decrease cervical spine injuries in a men\u27s professional rugby union team? A retrospective analysis

Cervical spine injuries in Rugby Union are a concerning issue at all levels of the game. The primary aim of this retrospective analysis conducted in a professional Rugby Union squad was to determine whether a 26-week isometric neck strengthening intervention program (13-week strengthening phase and 13- week maintenance phase) was effective in reducing the number and severity of cervical spine injuries. The secondary aim was to determine whether at week five, where the program had been the similar for all players, there was increased isometric neck strength. All 27 players who were common to both the 2007- 2008 and 2008-2009 seasons were included in this analysis and data was extracted from a Sports Medicine/Sports Science database which included the squad\u27s injury records. Primary outcome variables included; the number of cervical spine injuries and the severity of these injuries as determined by the total number of days lost from training and competition. Secondary outcome variables included isometric neck strength in flexion, extension and left and right lateral flexion. Using nonparametric statistical methods, no significant differences were evident for the total number of cervical spine injuries (n = 8 in 2007-2008, n = 6 in 2008-2009) or time loss due to these injuries (100 days in 2007-2008, 40 days in 2008-2009). However, a significant (p = 0.03) reduction in the number of match injuries was evident from 2007-2008 (n = 11) to 2008-09 (n = 2). Nonsignificant increases in isometric neck strength were found in all directions examined. A significant reduction in the number of match injuries was evident in this study. However, no other significant changes to primary outcome variables were achieved. Further, no significant increases in isometric neck strength were found in this well-trained group of professional athletes

The Proper Motion of the Central Compact Object RX J0822-4300 in the Supernova Remnant Puppis A

Using the High Resolution Camera (HRC) aboard the Chandra X-ray Observatory, we have re-examined the proper motion of the central compact object RX J0822-4300 in the supernova remnant Puppis A. New data from 2010 August, combined with three archival data sets from as early as 1999 December, provide a baseline of 3886 days (more than 10 1/2 years) to perform the measurement. Correlating the four positions of RX J0822-4300 measured in each data set implies a projected proper motion of mu 71 \pm 12 masy. For a distance of 2 kpc this proper motion is equivalent to a recoil velocity of 672 \pm 115 km/s. The position angle is found to be 244 \pm 11 degrees. Both the magnitude and direction of the proper motion are in agreement with RX J0822-4300 originating near the optical expansion center of the supernova remnant. For a displacement of 371 \pm 31 arcsec between its birth place and today's position we deduce an age of (5.2 \pm 1.0) 10^3 yrs for RX J0822-4300. The age inferred from the neutron star proper motion and filament motions can be considered as two independent measurements of the same quantity. They average to 4450 \pm 750 yrs for the age of the supernova remnant Puppis A.Comment: Accepted for publication in the Astrophysical Journa

Monitoring Water Quality on Tributary Inflows to Lake Mead and on a Transect of the Overton Arm

The USGS, in cooperation with the NPS and BOR (Bureau of Reclamation), is collecting water quality data to determine the temporal changes and spatial distributions of natural and anthropogenic compounds entering the Overton Arm of Lake Mead. These efforts and others already underway on the lake by BOR, USGS, and SNWA will aid in the development of a reservoir model of the lake. The effects of the flood flows on the water quality of the Overton Arm are largely unknown and necessary for model development and verification. Water quality physical parameters are continuously monitored near the mouth of the Virgin and Muddy Rivers using multi-parameter sondes. Water samples are collected quarterly at both sites and analyzed for major ions, trace elements, nutrients, pesticides, total organic carbon, indicator bacteria, and suspended sediment. During flows that exceed the 1.5 year flood, additional data collection occurs. Water samples will be collected at both river sites and analyzed for the same constituents as quarterly samples and hourly suspended sediment samples will be collected with an automatic sampler during the peak event the discharge plume into Lake Mead will be tracked by monitoring changes in sediment concentration and water quality in the Overton Arm

Effects of soft contact lenses as an alternative to topical anesthesia when utilizing the pneuma-tonometer

The purpose of this study was two-fold. We attempted to determine if valid intraocular pressure readings could be obtained when utilizing the Digilab Pneuma-tonometer over a soft contact lens in place of an anesthetic on a patient\u27s eye. We also attempted to determine the nature of any difference in patient sensation between utilizing the tonometer with a soft lens versus utilization with a topical corneal anesthetic. Our results indicated that soft lenses allow accurate readings over a range of normal pressures. We also found that no significant difference in sensation existed between the two conditions (contact lens versus anesthetic). We found that utilizing a soft lens during the tonometric procedure was surprisingly uncomplicated, even on inexperienced patients. The results of this study suggest that the technique of utilizing soft lenses with the Pneuma-Tonometer is practical and will yield valid readings over a normal range of pressures

Quantitative shadowgraphy and proton radiography for large intensity modulations

Shadowgraphy is a technique widely used to diagnose objects or systems in various fields in physics and engineering. In shadowgraphy, an optical beam is deflected by the object and then the intensity modulation is captured on a screen placed some distance away. However, retrieving quantitative information from the shadowgrams themselves is a challenging task because of the non-linear nature of the process. Here, a novel method to retrieve quantitative information from shadowgrams, based on computational geometry, is presented for the first time. This process can be applied to proton radiography for electric and magnetic field diagnosis in high-energy-density plasmas and has been benchmarked using a toroidal magnetic field as the object, among others. It is shown that the method can accurately retrieve quantitative parameters with error bars less than 10%, even when caustics are present. The method is also shown to be robust enough to process real experimental results with simple pre- and post-processing techniques. This adds a powerful new tool for research in various fields in engineering and physics for both techniques

Cranfield University centre of excellence in counter-terrorism

The formation of Cranfield University’s Counterterrorism Centre of Excellence was announced in late summer 2017. It has been established in conjunction with Pool Re, a mutual reinsurer which underwrites over £2 trillion of exposure to terrorism risk in the UK. The centre will provide thought leadership in catastrophic and unconventional terrorism loss assessment and mitigation so as to improve the UK’s economic resilience. We introduce the reinsurance industry for a technical audience to explain the rationale for the Counterterrorism Centre of Excellence. The centre’s aims and some results from preliminary simulations on explosive blast in a complex city centre performed in collaboration with reinsurance broker Guy Carpenter are presented. The prospects for physics-based simulation, for terrorist insurance loss estimation and for encouraging mitigation in reinsurance are outlined

Effects of Initial Flow on Close-In Planet Atmospheric Circulation

We use a general circulation model to study the three-dimensional (3-D) flow and temperature distributions of atmospheres on tidally synchronized extrasolar planets. In this work, we focus on the sensitivity of the evolution to the initial flow state, which has not received much attention in 3-D modeling studies. We find that different initial states lead to markedly different distributions-even under the application of strong forcing (large day-night temperature difference with a short "thermal drag time") that may be representative of close-in planets. This is in contrast with the results or assumptions of many published studies. In general, coherent jets and vortices (and their associated temperature distributions) characterize the flow, and they evolve differently in time, depending on the initial condition. If the coherent structures reach a quasi- stationary state, their spatial locations still vary. The result underlines the fact that circulation models are currently unsuitable for making quantitative predictions (e.g., location and size of a "hot spot") without better constrained, and well posed, initial conditions.Comment: Accepted for publication in the Astrophysical Journal; 23 pages, 9 figures