The effect of post Pangea subduction on global mantle tomography and convection

There is an excellent correlation between tomographic patterns and global tectonics in the upper 200 km of the mantle. Below this depth there is little relationship with present tectonic provinces. Most of the power in the tomography is in the longest wavelengths (ℓ=1–3) with ℓ=2 generally dominant. This is quite different from expectations based on mantle convection models. The question then arises, what causes the long wavelength variations mapped by seismic techniques? We investigate the hypotheses that past locations of supercontinents and subduction may control temperature variations in the mantle. We look for correlations between Pangea and post-Pangeatic subduction and seismic velocity variations at various depths. The best correlations with time integrated slab locations occur near the base of the uppermantle, suggesting that slabs bottom out in the mesosphere. The Pangea hemisphere has a colder than average uppermantle, probably due to circum- and intra-Pangea subduction. Hotspots and ridges avoid regions cooled by subduction over the past 180 Ma. The presence of large continents at the surface and large areas of cold slab at depth explain the dominance of long wavelengths in the mantle's thermal structure, despite the high Rayleigh number

Results of the 2001 Becoming an Outdoor-Woman Survey

INHS Human Dimensions Research Program and Illinois Department of Natural Resourcesunpublishednot peer reviewedOpe

Results of the 2003-2004 Illinois Youth Hunter Survey

Federal Aid Project Number W-112-R-13, Job Number 103.1, Wildlife Restoration Fund, July 1, 2003 - Sept. 30, 2004Report issued on: December 22, 200

Spherical Harmonic Correlation of Pangea and Subducted Slab with Global Seismic Tomography

A map of continental Pangea, circa 180 Ma, was digitized and expanded numerically in spherical harmonics to degree I = 8 (Figure 1). Also, an estimate of the distribution of lithospheric slab subducted since 180 Ma was obtained from plate reconstruction maps, and this area of distribution was digitized and expanded in spherical harmonics to l = 8 (Figure 2). The distribution of subducted slab was determined by overlaying successive map reconstructions of the subduction zones from 180 Ma to the present and digitizing the area which fell ·between the extreme positions of the trenches over that time. Subduction zones appeared to shift direction, backtracking over themselves instead of moving in a constant direction away from their 180 Ma positions. This indicates changes in relative plate motions that were not clearly indicated on the maps used. The areas of Pangea and the subducted slab were digitized to 5° by 5° resolution. The power spectrum of the spherical harmonic expansion for Pangea indicates the dominance of the degree 1 component (Figure 3). The power in degree 3 is most likely the result of the Tethys Sea which cuts into the eastern margin of Pangea. The power spectrum for the expansion of the subducted slab peaks for degrees 2 and 3 (Figure 6). Both of these expansions were correlated with the 11 depth layers (Table 1) of Tanimoto's (1990) global seismic S-wave and Love wave tomography for degrees l = 1 to 6. For his tomography, the degree l = 2 has the largest power in all layers except shell 5, where l = 3 is strongest. Tanimoto is concerned that aliasing may occur for the layers 4 to 6. The correlation between the expansion of Pangea and Tanimoto's tomography is strongest for degree 1 at the bottom of the upper" mantle with a correlation coefficient of r = -0.90 (Figure 4, see note concerning the sign of correlations). Degree 3 shows a high correlation at the top of the lower mantle with r = 0.82 for shell 5 (Figure 5). The high power coefficient at degree 3 for shell 5 in Tanimoto's tomography lends added weight to this correlation. The reversal of sign in the correlation for degree 3 relative to degree 1 is interesting. The correlation between the expansion of the subducted slab and Tanimoto's tomography are strongest for degrees 2 and 3. Degree 2 shows its strongest correlation, r = - 0.79 at the bottom of the lower mantle; there is a somewhat weaker correlation at the bottom of the lower mantle (Figure 7). Degree 3 has a strong correlation of r = -0.70 at the top of the lower mantle (Figure 8). Overall, the correlations of these two degrees indicate a strong tomographic signal from cold, fast material around the 670 km discontinuity. Previous researchers have reached conflicting conclusions about the path of subducting slab. The primary argument concerns whether the slab cross the 670 km discontinuity. This is a significant point because the answer is strongly dependent on the nature of the boundary, and so would clarify many issues if it were known. Attempts to use seismic ray travel-time anomalies of deep earthquakes to image the dip of the slab further down have not all reached the same results. Fischer et al. (1988) find a near-vertical dip, Zhou et al. (1989) find a sub-horizontal dip at the depth of the 670 discontinuity. Recent discussions of mantle chemistry (Anderson 1989, and Ringwood and Irifune 1988) seem to favor the slab dipping to horizontal, though some slabs might punch through steeply and reach the bottom of the mantle. The problem has also been modeled experimentally in the lab by Kincaid and Olson (1987), and, depending on the density variation across the discontinuity, different regimes of subduction were found - from near vertical dip for no density variation, to horizontal dip for a large density variation. This experimental work generates other useful questions as well, about the significance of dip angle and trench migration. Richards and Engebretson (Fall 1990 AGU Abstract) correlate seismic tomography to sinking slabs, but only for the lower mantle body wave tomographies of Dziewonski (1984) and Hager and Clayton (1988). Their correlation for degree 3 with these tomographies is about the same as the correlations presented here for degree 3. However, their correlations for degrees 1 and 2 are higher. For these degrees, the correlations presented here are highest in the upper mantle and suggest that a significant fraction of the subducted slab is going no deeper than the 670 discontinuity

Analysis of Urobilinogen and Urine Bilirubin for Intra-Abdominal Injury in Blunt Trauma Patients

OBJECTIVE: To determine the point prevalence of urine bilirubin, urine hemoglobin and urobilinogen in blunt trauma patients, and to evaluate its utility as a screening tool for intra-abdominal injury.METHODS: Data analysis of 986 consecutive trauma patients of which 698 were adult blunt trauma patients. Five-hundred sixteen subjects had a urinalysis and a CT scan of the abdomen/pelvis or exploratory laparotomy. We reviewed initial urinalysis results from trauma patients in the emergency department (ED) for the presence of urine hemoglobin, uroblinogen and urine bilirubin. Computed tomography (CT) scan results and operative reports were reviewed from the trauma registry for evidence of liver laceration, spleen laceration, bowel or mesenteric injuries.RESULTS: There were 73 injuries and 57/516 patients (11%) with intra-abdominal injury. Urinalysis was positive for urobilinogen in 28/516 (5.4%) patients, urine bilirubin in 15/516 (2.9%) patients and urine hemoglobin in 313/516 (61%) patients. Nineteen/forty-seven (4%) subjects had liver lacerations, 28/56 (5%) splenic lacerations, and 15/5 (3%) bowel or mesenteric injury. Comparing the proportion of patients that had urobilinogen detected in the group with and without intra-abdominal injury, 8/28 (29%) subjects with urobilinogen, 5/15 (33%) subjects with bilirubin and 47/313 (15%) subjects with urine hemoglobin were found to have liver lacerations, spleen lacerations, or bowel/mesenteric injuries. Preexisting liver or biliary conditions were not statistically associated with elevation of urine bilirubin, urine hemoglobin or urobilinogen on initial urinalysis after blunt abdominal trauma. Point prevalence for urobilinogen, urine bilirubin and urine hemoglobin are 5.43% (28/516), 2.91% (15/516) and 60.7% (313/516) respectively.CONCLUSIONS: The utility of the initial routine urinalysis in the ED for adult blunt abdominal trauma patients should not be used as a screening tool for the evaluation of intra-abdominal injury

Millimeter and Submillimeter Survey of the R Corona Australis Region

Using a combination of data from the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO), the Arizona Radio Observatory Kitt Peak 12m telescope and the Arizona Radio Observatory 10m Heinrich Hertz Telescope, we have studied the most active part of the R CrA molecular cloud in multiple transitions of Carbon Monoxide, HCO$^+$ and 870\micron continuum emission. Since R CrA is nearby (130 pc), we are able to obtain physical spatial resolution as high as 0.01pc over an area of 0.16 pc$^2$, with velocity resolution finer than 1 km/s. Mass estimates of the protostar driving the mm-wave emission derived from HCO$^+$, dust continuum emission and kinematic techniques point to a young, deeply embedded protostar of $\sim$0.5-0.75 M$_\odot$, with a gaseous envelope of similar mass. A molecular outflow is driven by this source that also contains at least 0.8 M$_\odot$ of molecular gas with $\sim$0.5 L$_\odot$ of mechanical luminosity. HCO$^+$ lines show the kinematic signature of infall motions as well as bulk rotation. The source is most likely a Class 0 protostellar object not yet visible at near-IR wavelengths. With the combination of spatial and spectral resolution in our data set, we are able to disentangle the effects of infall, rotation and outflow towards this young object.Comment: 29 pages, 9 figures. Accepted for publication in the Astrophysical Journa

Does aerial baiting for controlling feral cats in a heterogeneous landscape confer benefits to a threatened native meso-predator?

Introduced mammalian predators can have devastating impacts on recipient ecosystems and disrupt native predator–prey relationships. Feral cats (Felis catus) have been implicated in the decline and extinction of many Australian native species and developing effective and affordable methods to control them is a national priority. While there has been considerable progress in the lethal control of feral cats, effective management at landscape scales has proved challenging. Justification of the allocation of resources to feral cat control programs requires demonstration of the conservation benefit baiting provides to native species susceptible to cat predation. Here, we examined the effectiveness of a landscape-scale Eradicat® baiting program to protect threatened northern quolls (Dasyurus hallucatus) from feral cat predation in a heterogeneous rocky landscape in the Pilbara region of Western Australia. We used camera traps and GPS collars fitted to feral cats to monitor changes in activity patterns of feral cats and northern quolls at a baited treatment site and unbaited reference site over four years. Feral cat populations appeared to be naturally sparse in our study area, and camera trap monitoring showed no significant effect of baiting on cat detections. However, mortality rates of collared feral cats ranged from 18–33% after baiting, indicating that the program was reducing cat numbers. Our study demonstrated that feral cat baiting had a positive effect on northern quoll populations, with evidence of range expansion at the treatment site. We suggest that the rugged rocky habitat preferred by northern quolls in the Pilbara buffered them to some extent from feral cat predation, and baiting was sufficient to demonstrate a positive effect in this relatively short-term project. A more strategic approach to feral cat management is likely to be required in the longer-term to maximise the efficacy of control programs and thereby improve the conservation outlook for susceptible threatened fauna

The Contrasting Effects of an Action Video Game on Visuo-Spatial Processing and Proactive Cognitive Control

First person shooter or action video games represent one of the most popular genres within the gaming industry. Studies reveal that action gaming experience leads to enhancements of visuo-spatial processing. In contrast, some correlational evidence reveals that experience with action video games may be associated with reduced proactive cognitive control. The two primary goals of the current study were to test the causal nature of the effect of action gaming on proactive cognitive control and to examine whether an increase in visuo-spatial processing and a decrease in proactive cognitive control arise from the same amount of experience playing an action video game. Participants completed tasks measuring visuo-spatial processing and cognitive control before and after 10 practice sessions involving one of three video games or were assigned to a no gaming experience control group. The data revealed the typical increase in visuo-spatial processing and a decrease in proactive, but not reactive, cognitive control following action game training. The sizes of these two training effects were similar in magnitude, but interpretation of the effects was constrained by baseline differences between the four groups of subjects. The possibility of a causal effect of action gaming on proactive cognitive control is interesting within the context of correlational evidence linking greater action gaming experience to reduced cognitive control, poor decision making, and increased impulsivity

Creating the Capacity to Screen Deaf Women for Perinatal Depression [poster]

There are approximately 1 million Deaf women in the U.S. who depend on American Sign Language (ASL) for communication. Although Deaf women become pregnant and enter motherhood at rates similar to hearing women, Deaf women attend fewer prenatal appointments, receive less information from their physicians, are less satisfied with physician concern and quality of communication, and are less satisfied with their prenatal care. These barriers persist after childbirth, leaving Deaf mothers with little professional support for struggles with postnatal healthcare, breastfeeding, and childcare. Combined with pre-existing mental health disparities observed among members of the Deaf community, such barriers leave Deaf women especially vulnerable to development or exacerbation of depression during the perinatal period (i.e., during pregnancy or within one year postpartum). Expert groups recommend depression screening as a standard of perinatal care - the first critical step to direct women to treatment. Yet, available screening tools are not accessible to Deaf women due to documented low levels of English literacy and health literacy. It is, therefore, critical to develop and validate tools to screen for depression among Deaf perinatal women so they may access the same standard of care as other perinatal women. To address these barriers, our team is conducting a one-year, community-engaged pilot study to develop and perform preliminary psychometric analyses on an ASL translation of the Edinburgh Postnatal Depression Scale (EPDS). During the poster session, we will outline our unique community-engaged research methods, as well as exhibit the first draft of the ASL EPDS

Arginine side chain interactions and the role of arginine as a gating charge carrier in voltage sensitive ion channels

Gating charges in voltage-sensing domains (VSD) of voltage-sensitive ion channels and enzymes are carried on arginine side chains rather than lysine. This arginine preference may result from the unique hydration properties of the side chain guanidinium group which facilitates its movement through a hydrophobic plug that seals the center of the VSD, as suggested by molecular dynamics simulations. To test for side chain interactions implicit in this model we inspected interactions of the side chains of arginine and lysine with each of the 19 non-glycine amino acids in proteins in the protein data bank. The arginine guanidinium interacts with non-polar aromatic and aliphatic side chains above and below the guanidinium plane while hydrogen bonding with polar side chains is restricted to in-plane positions. In contrast, non-polar side chains interact largely with the aliphatic part of the lysine side chain. The hydration properties of arginine and lysine are strongly reflected in their respective interactions with non-polar and polar side chains as observed in protein structures and in molecular dynamics simulations, and likely underlie the preference for arginine as a mobile charge carrier in VSD