Prediction Model for 30-day Outcomes Among Emergency Department Patients with Lower Gastrointestinal Bleeding

Introduction: There are currently no robust tools available for risk stratification of emergency department (ED) patients with lower gastrointestinal bleed (LGIB). Our aim was to identify risk factors and develop a preliminary model to predict 30-day serious adverse events among ED LGIB patients.Methods: We conducted a health records review including adult ED patients with acute LGIB. We used a composite outcome of 30-day all-cause death, recurrent LGIB, need for intervention to control the bleeding, and severe adverse events resulting in intensive care unit admission. One researcher collected data for variables and a second researcher independently collected 10% of the variables for inter-observer reliability. We used backward multivariable logistic regression analysis and SELECTION=SCORE option to create a preliminary risk-stratification tool. We assessed the diagnostic accuracy of the final model.Results: Of 372 patients, 48 experienced an adverse outcome. We found that age ≥75 years, hemoglobin ≤100 g/L, international normalized ratio ≥2.0, ongoing bleed in the ED, and a medical history of colorectal polyps were statistically significant predictors in the multivariable regression analysis. The area under the curve (AUC) for the model was 0.83 (95% confidence interval, 0.77-0.89). We developed a scoring system based on the logistic regression model and found a sensitivity 0.96 (0.90-1.00) and specificity 0.53 (0.48-0.59) for a cut-off score of 1.Conclusion: This model showed good ability to differentiate patients with and without serious outcomes as evidenced by the high AUC and sensitivity. The results of this study could be used in the prospective derivation of a clinical decision tool

String Quartet No. 1

String Quartet No. 1, by Jeffrey Scott Perry, is absolute music. It uses unconventional techniques that challenge the interpretations of performers and listeners. Performers treat tempos and phrasing flexibly that yields a different version of the piece with each performance. The structure is Rounded Binary, but is manipulated to be purposefully obscure until the last measures of the piece. This is accomplished by incorporating ideas of motivic development into the overall form. The first four motifs are the source of all subsequent material. Therefore, motivic development is vital to the construction of the piece and becomes a unifying factor between both melodic and formal identities. There is no intentional harmonic progression. This directs the listener to focus on the tension and release that occurs linearly and not vertically. Musical color, without the use of tertian harmony, relies on other music elements such as timbre, texture, tempo, dynamics, and transposition

Effects of sputter deposition parameters on stress in tantalum films with applications to chemical mechanical planarization of copper

Attempts to introduce a CMP process for copper damascene features at Rochester Institute of Technology were stymied by adhesion failures of the Ta/Cu film stack. This work was undertaken to investigate the effect of stress in the films on adhesion and to develop a viable CMP process for Cu damascene technology. In depth studies of stress as a function of sputter deposition conditions revealed that stress in Ta layers could vary from -1700 MPa compression to +800 MPa tensile for deposition pressures over a range of 2-20 mTorr for films having a nominal thickness of 0.25 μm. For a fixed pressure, stress could vary from -1500 to +800 MPa for thicknesses ranging from 24 to 225 nm. More importantly, target aging was shown to result in a change in stress for fixed deposition parameters, such as pressure and power. Control of the stress in these films is critical as a substantial difference in CMP removal rates for tantalum films having -400 to -1200 MPa of compressive stress was observed. In addition, the top copper layer will adhere to Ta films in a specific range of compressive stress. A 50 nm film stack of TaN/Ta with varying thickness ratios of the two metals was fabricated that exhibited nearly constant compressive stress. This deposition process for the TaN/Ta barrier layer was developed utilizing fixed voltage, not power as the deposition parameter. These studies resulted in a sputter process for TaN/Ta/Cu that exhibited good adhesion to SiO2, both for blanket and patterned films. A copper damascene process has been developed using a film system that adhered well to SiO2. Wafers were characterized for planarity both within die and within wafer, as well as wafer-to-wafer. The most promising deposition and polish processes were employed to produce a metal gate metal oxide semiconductor (MOS) capacitor and characterized by measuring the maximum electric field of the gate oxide before it would break down. The planarized damascene features were achieved that exhibited ≤ 30 nm of topology as viewed by profilometery and AFM. Results of breakdown studies of MOS capacitors were confounded by particulate effects, but the capacitors produced by CMP were on par with sputtered films patterned by photolithography. I would like to express my gratitude to Dr. Michael Jackson for taking me on as his graduate student and for his guidance throughout this project. I am grateful for Dr. Santosh Kurinec, Dr. Richard Lane and Dr. Christopher Hoople for being on my thesis committee and being willing to donate time to answer my questions. I acknowledge Dr. Tom Blanton for his generous donation of XRD analysis and expertise. I also appreciate the help of Daniel Brown for writing a program to perform stress calculations. This endeavor saved a significant amount of time. I give my most sincere appreciation to my father for providing help in numerous ways

Tyrannicide: Forging an American Law of Slavery in Revolutionary South Carolina and Massachusetts

Contested Understandings of Slavery and Freedom in the Republic’s Formative Years Blanck frames her narrative around thirty-four slaves from South Carolina’s Waccamaw Peninsula who in May 1779 were taken by British privateers. Within a month, however, and after a series of naval battles, ...

Protectors of the Peace: Baptist Church Tribunals and the Construction of American Religious and Civil Authority, 1780-1860

This dissertation argues that Baptist churches served as important legal sites in the trans-Appalachian West from the Revolutionary period to the outbreak of the Civil War. By looking at how members and non-members approached their local churches for matters of dispute resolution over time and space, it illuminates a local legal culture transforming under the pressures of legal, economic, religious, and cultural change. Legislative enactments and new understandings of the family gradually weakened churches\u27 authority over their members\u27 domestic relations. An expanding market-economy necessitating predictable and presumably neutral dispute resolution led many to decry their churches\u27 factionalist-produced decrees. Some churches refused to get involved with messy economic disputes and sanctioned members\u27 resort to state-based law. Others emerged as sites through which whites strengthened the region\u27s consolidating racial hierarchy, disproportionately focusing their disciplinary proceedings at their black brethren. Furthermore, religious dissension wrecked trans-Appalachian Baptist churches during the 1820s and 1830s, leading to a decline in disciplinary activities. Divided by doctrinal schism, some opposing church factions engaged in lengthy legal contests and opened the door for state authorities to meddle in ecclesiastical affairs. In the end, this dissertation contends that the persistence of churches\u27 law-producing operations during the post-Revolutionary period--and the practice\u27s later diminishment during the antebellum era--shaped the contours of American religious and civil authority and held repercussions for the process of separating church from state

Fouling in silicon microchannel designs used for IC chip cooling and its mitigation

Particulate fouling studies with alumina and silica dispersions were performed in silicon, rectangular microchannels having hydraulic diameters between 220-225 μm. The particulates used ranged from the colloidal size range up to tens of microns in size (for particle aggregates). Data show for the most part the absence of particle depositions within the microchannels. This is even the case when there is an electrostatic attraction between the particles and the microchannel surface. The primary reason for this is due to the high wall shear stress at the microchannel walls. In contrast, the headers for the microchannels are quite susceptible to particulate fouling under the same conditions. This is because the shear stress at the surface is lower. This fouling within the header, however, does not provide an increase in pressure drop within the microchannel device. Moreover, depositions within the header region can be mitigated with proper pH adjustment. There is a secondary effect in particulate fouling when fibrous elements exist within the particle dispersion. The fouling behavior due to fibrous material is quite different. In fact, the presence of fibers is extremely detrimental to pressure drops within a microchannel device. A multi-scale force balance model for particulate fouling is developed. It uses conventional theories on the forces between a particle and a wall which are extended to particulate fouling within a microchannel device. The model covers a scale spanning several orders of magnitude. In addition, it includes van der Waals forces, electrostatic forces, fluidmechanics- related forces due to shear/lift, and a body force due to gravity

Can Emergency Physicians Perform Carotid Artery Point-of-Care Ultrasound to Detect Stenosis in Patients with TIA and Stroke? A Pilot Study

Introduction: Patients with severe, symptomatic carotid stenosis can have their subsequent stroke risk reduced by surgical intervention if performed soon after a transient ischemic attack (TIA) or stroke. Patients presenting to an emergency department (ED) without computed tomography angiography (CTA) with TIA/stroke, may require transfer to another hospital for imaging to rule out carotid artery stenosis. The objective of this study was to determine the test characteristics of carotid artery point-of-care ultrasound (POCUS) in detecting greater than 50% stenosis in patients presenting with TIA/stroke.Methods: We conducted a prospective cohort study on a convenience sample of adult patients presenting to a comprehensive stroke centre with TIA or stroke between June–October 2017. Carotid POCUS was performed. Primary outcome measure, stenosis ≥ 50%, was determined by the final radiology report of CTA. A blinded POCUS expert separately reviewed the archived carotid POCUS scans. We calculated sensitivity and specificity for stenosis ≥ 50%.Results: We conducted POCUS on 75 patients, of which 70 were included in our analyses. Of those 70, 14.3% were diagnosed with greater than 50% stenosis. Carotid POCUS performed as follows: sensitivity 70.0% (95% confidence interval [CI], 34.8%-93.3%); specificity 86.7% (95% CI, 75.4%-94.1%); positive likelihood ratio (LR +) 5.3 (95% CI, 1.2-9.3); negative likelihood ratio (LR -) 0.4 (95% CI, 0.0-0.7). The inter-rater reliability between POCUS performer interpretation and expert interpretation had moderate agreement (k = 0.68). Scans took a mean 6.2 ± 2.2 minutes to complete.Conclusion: Carotid POCUS has low to moderate association with CTA for detection of carotid artery stenosis ≥ 50%. Further research and investigation is needed prior to widespread use of carotid POCUS in patients with acute cerebral ischemia. Additionally, external validity is likely affected by availability of training, maintenance of competency, and experience in more rural centres

Recursive conditional means image denoising

Methods and composition for denoising digital camera images are provided herein. The method is based on directly measuring the local statistical structure of natural images in a large training set that has been corrupted with noise mimicking digital camera noise. The measured statistics are conditional means of the ground truth pixel value given a local context of input pixels. Each conditional mean is the Bayes optimal (minimum mean squared error) estimate given the specific local context. The conditional means are measured and applied recursively (e.g., the second conditional mean is measured after denoising with the first conditional mean). Each local context vector consists of only three variables, and hence the conditional means can be measured directly without prior assumptions about the underlying probability distributions, and they can be stored in fixed lookup tables.Board of Regents, University of Texas Syste