3,954 research outputs found
The Lantern Vol. 38, No. 1, Winter 1971
• Thoughts for Today • Love\u27s Trilogy • He\u27s My Mountain Now • Activity • Crazy River • Seeyousoon • Wild Stallion • A Search • Nest • Depression • Bait • The Gentle Carpenter • An Ode to Ralph • Rain • Memories • Paranoiac Dreaming • The Two Last People on Earth • Brokedown Blues • Francis Baconhttps://digitalcommons.ursinus.edu/lantern/1099/thumbnail.jp
Contemporary management of acute mesenteric ischemia: Factors associated with survival
AbstractPurpose: Acute mesenteric ischemia (AMI) is a morbid condition with a difficult diagnosis and a high rate of complications, which is associated with a high mortality rate. For the evaluation of the results of current management and the examination of factors associated with survival, we reviewed our experience. Methods: The clinical data of all the patients who underwent operation for AMI between January 1, 1990, and December 31, 1999, were retrospectively reviewed, clinical outcome was recorded, and factors associated with survival rate were analyzed. Results: Fifty-eight patients (22 men and 36 women; mean age, 67 years; age range, 35 to 96 years) underwent study. The cause of AMI was embolism in 16 patients (28%), thrombosis in 37 patients (64%), and nonocclusive mesenteric ischemia (NMI) in five patients (8.6%). Abdominal pain was the most frequent presenting symptom (95%). Twenty-five patients (43%) had previous symptoms of chronic mesenteric ischemia. All the patients underwent abdominal exploration, preceded with arteriography in 47 (81%) and with endovascular treatment in eight. Open mesenteric revascularization was performed in 43 patients (bypass grafting, n = 22; thromboembolectomy, n = 19; patch angioplasty, n = 11; endarterectomy, n = 5; reimplantation, n = 2). Thirty-one patients (53%) needed bowel resection at the first operation. Twenty-three patients underwent second-look procedures, 11 patients underwent bowel resections (repeat resection, n = 9), and three patients underwent exploration only. The 30-day mortality rate was 32%. The rate was 31% in patients with embolism, 32% in patients with thrombosis, and 80% in patients with NMI. Multiorgan failure (n = 18 patients) was the most frequent cause of death. The cumulative survival rates at 90 days, at 1 year, and at 3 years were 59%, 43%, and 32%, respectively, which was lower than the rate of a Midwestern white control population (P <.001). Six of the 16 late deaths (38%) occurred because of complications of mesenteric ischemia. Age less than 60 years (P <.003) and bowel resection (P =.03) were associated with improved survival rates. Conclusion: The contemporary management of AMI with revascularization with open surgical techniques, resection of nonviable bowel, and liberal use of second-look procedures results in the early survival of two thirds of the patients with embolism and thrombosis. Older patients, those who did not undergo bowel resection, and those with NMI have the highest mortality rates. The long-term survival rate remains dismal. Timely revascularization in patients who are symptomatic with chronic mesenteric ischemia should be considered to decrease the high mortality rate of AMI. (J Vasc Surg 2002;35:445-52.
Differential Cross Sections for Electron Capture from Helium by 25- to 100-keV Incident Protons
Experimentally and theoretically determined differential cross sections are reported for electron capture in collisions of protons with helium atoms for incident proton energies of 25, 30, 50, and 100 keV and for center-of-mass scattering angles of 0.0 to 2.0 mrad. The magnitudes of the experimentally determined differential cross sections decrease from 10-10 to 10-12 cm2/sr within the 0.0-0.8-mrad range of the center-of-mass scattering angle. At approximately 0.8 mrad a distinct change in the slope of the differential cross section is observed. The experimental results which are for capture into all bound states of hydrogen are compared with the theoretical results of a calculation for capture into the ground state using the two-state two-center atomic expansion method in the eikonal approximation. Good agreement between the theoretical and the experimental results is obtained with a static potential which accounts for screening of the helium nucleus by a single passive electron
The Lantern Vol. 36, No. 1, Winter 1970
• Reaction • Offering III • To a Conglomeration of No One in Particular • Mom\u27s Cookies • Sounds of War • Racetrack, August 2 • The Rain Pool • Eternal Optimist? • On the Slipperiness of Summer • First Snowfall • Tree--and Beyond • Eternal Stone • Thinking Abstract • Once • November • Lifewreck • Moon Travelin • Air-borne • Isn\u27t Dating Fun? • Escape • Why • #1 • Thoughts for a Saturday Night • A Non-Poem • A Trilogy in Haiku • The Poetry of Loving You • True Blues Projecthttps://digitalcommons.ursinus.edu/lantern/1096/thumbnail.jp
The Lantern Vol. 38, No. 2, Spring 1972
• Summer II • For a True Romantic • The Lyre Neglected • Hands • To a Friend • Sleep • The Wind\u27s Confusing Sounds • The Garden • The Child Has Come Among Us • The River and the Sea • The Ice • La Lamentation de la Fleur • Nous Sommes • Upon Becoming • See! • Feeling November • Transience • Clear • Isotopes of Reality • Just Yesterday • Emergence • Push • The Way Love Starts • Poetic Prosy • An Agreement • Spring 1930 • The Summers of \u2759, \u2760, \u2761 • Ode to Optometry • The Easter Bunny - Noble Beasthttps://digitalcommons.ursinus.edu/lantern/1100/thumbnail.jp
Towards an Intelligent Tutor for Mathematical Proofs
Computer-supported learning is an increasingly important form of study since
it allows for independent learning and individualized instruction. In this
paper, we discuss a novel approach to developing an intelligent tutoring system
for teaching textbook-style mathematical proofs. We characterize the
particularities of the domain and discuss common ITS design models. Our
approach is motivated by phenomena found in a corpus of tutorial dialogs that
were collected in a Wizard-of-Oz experiment. We show how an intelligent tutor
for textbook-style mathematical proofs can be built on top of an adapted
assertion-level proof assistant by reusing representations and proof search
strategies originally developed for automated and interactive theorem proving.
The resulting prototype was successfully evaluated on a corpus of tutorial
dialogs and yields good results.Comment: In Proceedings THedu'11, arXiv:1202.453
Haptoglobin Phenotype, Preeclampsia Risk and the Efficacy of Vitamin C and E Supplementation to Prevent Preeclampsia in a Racially Diverse Population
Haptoglobin's (Hp) antioxidant and pro-angiogenic properties differ between the 1-1, 2-1, and 2-2 phenotypes. Hp phenotype affects cardiovascular disease risk and treatment response to antioxidant vitamins in some non-pregnant populations. We previously demonstrated that preeclampsia risk was doubled in white Hp 2-1 women, compared to Hp 1-1 women. Our objectives were to determine whether we could reproduce this finding in a larger cohort, and to determine whether Hp phenotype influences lack of efficacy of antioxidant vitamins in preventing preeclampsia and serious complications of pregnancy-associated hypertension (PAH). This is a secondary analysis of a randomized controlled trial in which 10,154 low-risk women received daily vitamin C and E, or placebo, from 9-16 weeks gestation until delivery. Hp phenotype was determined in the study prediction cohort (n = 2,393) and a case-control cohort (703 cases, 1,406 controls). The primary outcome was severe PAH, or mild or severe PAH with elevated liver enzymes, elevated serum creatinine, thrombocytopenia, eclampsia, fetal growth restriction, medically indicated preterm birth or perinatal death. Preeclampsia was a secondary outcome. Odds ratios were estimated by logistic regression. Sampling weights were used to reduce bias from an overrepresentation of women with preeclampsia or the primary outcome. There was no relationship between Hp phenotype and the primary outcome or preeclampsia in Hispanic, white/other or black women. Vitamin supplementation did not reduce the risk of the primary outcome or preeclampsia in women of any phenotype. Supplementation increased preeclampsia risk (odds ratio 3.30; 95% confidence interval 1.61-6.82, p<0.01) in Hispanic Hp 2-2 women. Hp phenotype does not influence preeclampsia risk, or identify a subset of women who may benefit from vitamin C and E supplementation to prevent preeclampsia
Endoscopic Ultrasound and Related Technologies for the Diagnosis and Treatment of Pancreatic Disease - Research Gaps and Opportunities: Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop
A workshop was sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases to address the research gaps and opportunities in pancreatic endoscopic ultrasound (EUS). The event occurred on July 26, 2017 in 4 sessions: (1) benign pancreatic diseases, (2) high-risk pancreatic diseases, (3) diagnostic and therapeutics, and (4) new technologies. The current state of knowledge was reviewed, with identification of numerous gaps in knowledge and research needs. Common themes included the need for large multicenter consortia of various pancreatic diseases to facilitate meaningful research of these entities; to standardize EUS features of different pancreatic disorders, the technique of sampling pancreatic lesions, and the performance of various therapeutic EUS procedures; and to identify high-risk disease early at the cellular level before macroscopic disease develops. The need for specialized tools and accessories to enable the safe and effective performance of therapeutic EUS procedures also was discussed
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
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