389 research outputs found
Quantifying the Influence of Near-Surface Water-Energy Budgets on Soil Thermal Properties Using a Network of Coupled Meteorological and Vadose-Zone Instrument Arrays in Indiana, USA
Poster presented at American Geophysical Union Meeting, 2012.Weather stations that collect reliable, sustained meteorological data sets are becoming more widely distributed because of advances in both instrumentation and data server technology. However, sites collecting soil moisture and soil temperature data remain sparse with even fewer locations where complete meteorological data are collected in conjunction with soil data. Thanks to the advent of sensors that collect continuous in-situ thermal properties data for soils, we have gone a step further and incorporated thermal properties measurements as part of hydrologic instrument arrays in central and northern Indiana. The coupled approach provides insights into the variability of soil thermal conductivity and diffusivity attributable to geologic and climatological controls for various hydrogeologic settings. These data are collected to facilitate the optimization of ground-source heat pumps (GSHPs) in the glaciated Midwest by establishing publicly available data that can be used to parameterize system design models.
A network of six monitoring sites was developed in Indiana. Sensors that determine thermal conductivity and diffusivity using radial differential temperature measurements around a heating wire were installed at 1.2 meters below ground surface— a typical depth for horizontal GSHP systems. Each site also includes standard meteorological sensors for calculating reference evapotranspiration following the methods by the Food and Agriculture Organization (FAO) of the United Nations. Vadose zone instrumentation includes time domain reflectometry soil-moisture and temperature sensors installed at 0.3-meter depth intervals down to a 1.8-meter depth, in addition to matric potential sensors at 0.15, 0.3, 0.6, and 1.2 meters. Cores collected at 0.3-meter intervals were analyzed in a laboratory for grain size distribution, bulk density, thermal conductivity, and thermal diffusivity.
Our work includes developing methods for calibrating thermal properties sensors based on known standards and comparing measurements from transient line heat source devices. Transform equations have been developed to correct in-situ measurements of thermal conductivity and comparing these results with soil moisture data indicates that thermal conductivity can increase by as much as 25 percent during wetting front propagation. Thermal dryout curves have also been modeled based on laboratory conductivity data collected from core samples to verify field measurements, and alternatively, temperature profile data are used to calibrate near-surface temperature gradient models. We compare data collected across various spatial scales to assess the potential for upscaling near-surface thermal regimes based on available soils data. A long-term goal of the monitoring effort is to establish continuous data sets that determine the effect of climate variability on soil thermal properties such that expected ranges in thermal conductivity can be used to determine optimal ground-coupling loop lengths for GSHP systems
The simulation heuristic, paranoia, and social anxiety in a non-clinical sample
Background and objectives: Quality of reasoning within non-clinical paranoia and mental simulation of future paranoia themed events was investigated by use of a simulation task to determine whether paranoid individuals would be restricted or more adept at reasoning about paranoia relevant material in comparison to a social anxiety group and a group with low paranoia and social anxiety. Method: Participants (N = 63) were divided into the three groups based on paranoia and social anxiety scores. They were presented with the beginning and end of an imaginary situation and were asked to describe, step-by-step, what they imagined would happen between those two points. They were also administered a beads task to evaluate the jumping to conclusion decision making bias. Results: The prediction of more adept reasoning was not supported for paranoia. However, the social anxiety comparison group on average better simulated a scenario with congruent (socially anxious) thematic content compared to ones with non-congruent content. Further, in an exploratory analysis, jumping to conclusions bias was found to be positively related to goodness of simulation for paranoia themed scenarios within the paranoia group. Limitations: Study groups were relatively small and so power was an issue. Conclusion: The results are discussed in the context of the sometimes paradoxical findings in the area of cognitive biases and paranoia
Monitoring near-surface thermal properties in conjunction with energy and moisture budgets to facilitate the optimization of ground-source heat pumps in the glaciated Midwest
This poster was presented at the American Geophysical Union Fall Meeting 2011, San Francisco, Calif., on December 7, 2011. It was part of IN33C, Geothermal energy research and discovery II posters session.By exploiting the near-surface heat reservoir, ground-source heat pumps (GSHP) represent an important renewable energy technology that can be further developed by establishing
data sets related to shallow (<100m) thermal regimes. Although computer programs are
available for GSHP installers to calculate optimal lengths and configurations of
ground-coupling geothermal systems, uncertainties exist for input parameters that must first
be determined for these models. Input parameters include earth temperatures and thermal
properties of unconsolidated materials. Furthermore, thermal conductivity of sediments
varies significantly depending on texture and moisture content, highlighting the need to
characterize various unconsolidated materials under varying soil moisture regimes.
Regolith texture data can be, and often are, collected for particular installations, and are
then used to estimate thermal properties for system design. However, soil moisture and
temperature gradients within the vadose zone are rarely considered because of the difficulty
associated with collecting a sufficient amount of data to determine predominant moisture
and temperature ranges.
Six monitoring locations were chosen in Indiana to represent unique hydrogeologic settings
and near-surface glacial sediments. The monitoring approach includes excavating trenches
to a depth of 2 meters (a typical depth for horizontal GSHP installations) and collecting
sediment samples at 0.3-meter intervals to determine thermal conductivity, thermal
diffusivity, and heat capacity in the laboratory using the transient line heat source method.
Temperature sensors are installed at 0.3-meter intervals to continuously measure thermal
gradients. Water-content reflectometers are installed at 0.3, 1, and 2 meters to determine
continuous volumetric soil moisture. In-situ thermal conductivity and thermal diffusivity
are measured at 1.5 meters using a differential temperature sensor that measures radial
differential temperature around a heating wire. Micrometeorological data (precipitation,
insolation, ambient air temperature, relative humidity, and wind speed) are also collected to
determine surface energy and water budgets that drive fluxes of energy and moisture in the
shallow subsurface. By establishing continuous, year-round data, fluctuations in seasonal
energy budgets and unsaturated zone soil moisture can be considered such that GSHP
system designers can establish accurate end members for thermal properties, thereby
optimizing the ground-coupling component of GSHPs. These data will also provide
empirical controls such that soil moisture and temperature regimes can be spatially
distributed based on mapped soil units and hydrogeologic settings in Indiana
Indiana Shallow Geothermal Monitoring Network: A Test Bed for Optimizing Ground-Source Heat Pumps in the Glaciated Midwest
This poster was presented at the 46th Annual Meeting of the North-Central Section of the Geological Society of America, April 23-24, 2012.Ground-source heat pumps (GSHP) represent an important technology that can be further developed by collecting data sets related to shallow thermal regimes. Computer programs that calculate the required lengths and configurations of GSHP systems use specific input parameters related to the soil properties to enhance the accuracy of models and produce efficient system designs. The thermal conductivity of sediments varies significantly depending on texture, bulk density, and moisture content, and it is therefore necessary to characterize various unconsolidated materials under a wide range of moisture conditions. Regolith texture data are collected during some installations to estimate thermal properties, but soil moisture and temperature gradients within the vadose zone are rarely considered due to the difficulty of collecting sufficient amounts of data.
Six monitoring locations were chosen in Indiana to represent unique hydrogeological settings and glacial sediments. Trenches were excavated to a depth of 2 meters (a typical depth for horizontal GSHP installations) and sediment samples were collected at 0.3-meter intervals for a laboratory analysis of thermal conductivity, thermal diffusivity, bulk density, and moisture content. Temperature sensors and water-content reflectometers were installed in 0.3-meter increments to monitor changes in temperature and soil moisture with depth. In-situ thermal conductivity and thermal diffusivity were measured at 1.5-meters using a sensor that detects radial differential temperature around a heating wire. Micrometeorological data were also collected to determine the surface conditions and water budgets that drive fluxes of energy and moisture in the shallow subsurface.
Preliminary results indicate that increases in water content can increase thermal conductivity by as much as 30% during wetting front propagation. Although there is a change in temperature associated with the infiltration of wetting fronts, thermal conductivity appears to be independent of soil temperature. By establishing continuous data sets, fluctuations in seasonal energy budgets and unsaturated zone soil moisture can be determined. This information can then be used to establish accurate end members for thermal properties and improve the efficiency of geothermal systems
Psychometric evaluation of the ostomy complication severity index
PURPOSE: The purpose of this study was to evaluate the psychometric properties of a new instrument to measure incidence and severity of ostomy complications early in the postoperative period.
SUBJECTS AND SETTINGS: 71 participants were enrolled, most were men (52%), white (96%), and married or partnered (55%). The mean age of participants was 57 ± 15.09 years (mean ± SD). Fifty-two participants (84%) experienced at least 1 ostomy complication in the 60-day postoperative period. The research setting was 3 acute care settings within a large healthcare system in the Midwestern United States.
INSTRUMENT: We developed an evidence-based conceptual model to guide development and evaluation of a new instrument, the Pittman Ostomy Complication Severity Index (OCSI). The OCSI format includes Likert-like scale with 9 individual items scored 0 to 3 and a total score computed by summing the individual items. Higher scores indicate more severe ostomy complications.
METHOD: This study consisted of 2 phases: (1) an expert review, conducted to establish content validity; and (2) a prospective, longitudinal study design, to examine psychometric properties of the instrument. A convenience sample of 71 adult patients who underwent surgery to create a new fecal ostomy was recruited from 3 hospitals. Descriptive analyses, content validity indices, interrater reliability testing, and construct validity testing were employed.
RESULTS: Common complications included leakage (60%), peristomal moisture-associated dermatitis (50%), stomal pain (42%), retraction (39%), and bleeding (32%). The OCSI demonstrated acceptable evidence of content validity index (CVI = 0.9) and interrater reliability for individual items (k = 0.71-1.0), as well as almost perfect agreement for total scores among raters (ICC = 0.991, P = .001). Construct validity of the OCSI was supported by significant correlations among variables in the conceptual model (complications, risk factors, stoma care self-efficacy, and ostomy adjustment).
CONCLUSION: OCSI demonstrated acceptable validity and reliability and can be used to assess incidence and severity of ostomy complications in the early postoperative period. We found the OCSI to be brief, easy-to-use, and clinically practical. It can be used to (a) identify priority areas for nursing intervention related to the ostomy, (b) determine appropriate interventions to prevent or treat complications, and (c) evaluate the effects of nursing interventions designed to improve outcomes for patients with ostomies
Gastric Tube Placement in Children 1-215 Months Old
poster abstractFeeding by a nasogastric/orogastric (NG/OG) tube is preferred when the gastrointestinal system is functional and the need for assisted feeding is expected to be short-term. Preliminary studies in children show that between 21% and 44% of these tubes are placed incorrectly. When tubes are out of place, children can be seriously harmed, causing increased morbidity and occasionally death.
The aims of this study were to determine the best method to predict the insertion distance for placing NG/OG tubes and to determine the best clinical methods of testing the location of NG/OG tubes once they were inserted. A randomized clinical trial was conducted.
The three insertion-distance prediction methods tested were nose-ear-xiphoid (NEX); nose-ear-mid-umbilicus (NEMU); and age-related, height-based (ARHB). An abdominal radiograph was obtained immediately following tube insertion to determine the internal location of the tube tip and orifice(s).
Based on data from 95 children age 1-220 months (M = 51.8, SD = 54.9, median = 33.4), both the ARHB and NEMU methods were superior to NEX in placing the tube in the stomach (p = .0064). ARHB and NEMU were not significantly different from each other. NEX was frequently too short (41.93% of tube insertions) leaving the tube tip and/or orifices in the esophagus.
The three clinical methods of testing tube location were CO2 monitoring and measuring pH and bilirubin in tube aspirate. Measuring pH of tube aspirate was the superior clinical method of determining tube location. Aspirate was available for testing in 84 children (88.42%). Based on a pH cutoff of 5 (recommended by Metheny in fasting adults), the sensitivity was 26.67 (low), specificity was 80.60 (high), positive predictive value was 23.53 (low), and negative predictive value was 83.08 (high).
Measuring the NEX distance is the method most commonly used by nurses in practice; therefore, based on the results of this study and studies of other researchers, a practice change to either ARHB or NEMU should improve the safety of enteral feeding in children. Because of the low sensitivity in predicting misplaced tubes using pH, the superior clinical method, obtaining an abdominal x-ray to ensure placement in the stomach at the time of tube insertion is recommended
: Bringing a novel research into the classroom: Carbon sequestration as a new opportunity for science education
This poster was presented at the 41st Annual Conference of the Hoosier Association of Science Teachers, Inc. (HASTI), Indianapolis, Ind., February 9-11, 2011.Carbon sequestration technology is an emerging area of research that is rarely presented in the current middle and high school curriculum. This poster complements a concurrent lecture at HASTI (Kevin Ellet and Cristian Medina) and presents three objectives: (1) to introduce the topic of carbon sequestration as a promising area of research for the mitigation of global warming; (2) to show how this technology draws from different science disciplines (e.g. earth science, physics, chemistry, and mathematics) and thus offers new opportunities for science education; (3) to present skills study can learn by studying this technology, such as the use and display of quantitative data and the use of online resources to perform literature searches. This poster presents issues raised in the HASTI position paper “Science Institutions in Indiana: Global Perspectives” (http://www.hasti.org/paper1.html) and encourages discussion on how to maximize science learning in Indiana classrooms
Association between Ophthalmic Timolol and Hospitalisation for Bradycardia
Introduction. Ophthalmic timolol, a topical nonselective beta-blocker, has the potential to be absorbed systemically which may cause adverse cardiovascular effects. This study was conducted to determine whether initiation of ophthalmic timolol was associated with an increased risk of hospitalisation for bradycardia. Materials and Methods. A self-controlled case-series study was undertaken in patients who were hospitalised for bradycardia and were exposed to timolol. Person-time after timolol initiation was partitioned into risk periods: 1–30 days, 31–180 days, and >180 days. A 30-day risk period prior to initiating timolol was also included. All remaining time was considered unexposed. Results. There were 6,373 patients with at least one hospitalisation for bradycardia during the study period; 267 were exposed to timolol. Risk of bradycardia was significantly increased in the 31–180 days after timolol initiation (incidence rate ratio (IRR) = 1.93; 95% confidence interval (CI) 1.00–1.87). No increased risk was observed in the first 30 days or beyond 180 days of continuous exposure (IRR = 1.40; 95% CI 0.87–2.26 and IRR = 1.21; 95% CI 0.64–2.31, resp.). Conclusion. Bradycardia is a potential adverse event following timolol initiation. Practitioners should consider patient history before choosing a glaucoma regime and closely monitor patients after treatment initiation with topical nonselective beta-blocker eye drops
Comparing Bedside Methods of Determining Placement of Gastric Tubes in Children
Purpose
The purpose of this study was to compare the accuracy and predictive validity of pH, bilirubin, and CO2 in identifying gastric tube placement errors in children.
Design and Methods
After the tube was inserted into 276 children, the CO2 monitor reading was obtained. Fluid was then aspirated to test pH and bilirubin.
Results
Lack of ability to obtain tube aspirate was the best predictor of NG/OG placement errors with a sensitivity of 34.9% and a positive predictive value of 66.7%. Measuring pH, bilirubin, and CO2 of tube aspirate was less helpful.
Practice Implications
Health care providers should suspect NG/OG tube misplacement when no fluid is aspirated
On the origin and pathway of the saline inflow to the Nordic Seas: insights from models
The behaviours of three high-resolution ocean circulation models of the North Atlantic, differing chiefly in their description of the vertical coordinate, are investigated in order to elucidate the routes and mechanisms by which saline water masses of southern origin provide inflows to the Nordic Seas. An existing hypothesis is that Mediterranean Overflow Water (MOW) is carried polewards in an eastern boundary undercurrent, and provides a deep source for these inflows. This study, however, provides an alternative view that the inflows are derived from shallow sources, and are comprised of water masses of western origin, carried by branches of the North Atlantic Current (NAC), and also more saline Eastern North Atlantic Water (ENAW), transported northwards from the Bay of Biscay region via a ‘Shelf Edge Current’ (SEC) flowing around the continental margins. In two of the models, the MOW flows northwards, but reaches only as far as the Porcupine Bank (53°N). In third model, the MOW also invades the Rockall Trough (extending to 60°N). However, none of the models allows the MOW to flow northwards into the Nordic Seas. Instead, they all support the hypothesis of there being shallow pathways, and that the saline inflows to the Nordic Seas result from NAC-derived and ENAW water masses, which meet and partially mix in the Rockall Trough. Volume and salinity transports into the southern Rockall Trough via the SEC are, in the various models, between 25 and 100% of those imported by the NAC, and are also a similarly significant proportion (20–75%) of the transports into the Nordic Seas. Moreover, the highest salinities are carried northwards by the SEC (these being between 0.13 and 0.19 psu more saline at the southern entrance to the Trough than those in the NAC-derived waters). This reveals for the first time the importance of the SEC in carrying saline water masses through the RockallTrough and into the Nordic Seas. Furthermore, the high salinities found on density surfaces appropriate to the MOW in the Nordic Seas are shown to result from the wintertime mixing of the saline near-surface waters advected northwards by the SEC/NAC system. Throughout, we have attempted to demonstrate the extent to which the models agree or disagree with interpretations derived from observations, so that the study also contributes to an ongoing community effort to assess the realism of our current generation of ocean models
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