90 results on '"Timothy Ball"'
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2. Students’ Perception of the Classroom Environment: A Comparison between Innovative and Traditional Classrooms
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Lori Britt, Timothy Ball, Toni Whitfield, and Chang Wan Woo
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ComputingMilieux_COMPUTERSANDEDUCATION ,ComputingMilieux_MISCELLANEOUS - Abstract
As advanced classroom technologies are developed, more higher education institutions are building innovative classrooms. Previous studies have focused on students’ academic performances in innovative classrooms, but few compared students experienced between traditional and innovative classrooms. In comparing observations and self-reports of students taking similar classes in both traditional classrooms and innovative classrooms, we found that students in an innovative classroom were more satisfied with the classroom environment, sensed more community in innovative classrooms, and perceived these classrooms as more appropriate for their courses.
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- 2022
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3. Preliminary Results from a Wildfire Detection System Using Deep Learning on Remote Camera Images
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Morgan L. Welch, Carlton R. Pennypacker, J. Timothy Ball, and Kinshuk Govil
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010504 meteorology & atmospheric sciences ,Computer science ,Real-time computing ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Cloud computing ,02 engineering and technology ,01 natural sciences ,law.invention ,Software ,law ,0202 electrical engineering, electronic engineering, information engineering ,Wireless ,Geostationary Operational Environmental Satellite ,lcsh:Science ,0105 earth and related environmental sciences ,business.industry ,Fire detection ,Deep learning ,020206 networking & telecommunications ,machine learning ,Remote camera ,General Earth and Planetary Sciences ,Satellite ,lcsh:Q ,Artificial intelligence ,smoke detection ,business ,fire detection - Abstract
Pioneering networks of cameras that can search for wildland fire signatures have been in development for some years (High Performance Wireless Research & Education Network—HPWREN cameras and the ALERT Wildfire camera). While these cameras have proven their worth in monitoring fires reported by other means, we have developed a functioning prototype system that can detect smoke from fires usually within 15 min of ignition, while averaging less than one false positive per day per camera. This smoke detection system relies on machine learning-based image recognition software and a cloud-based work-flow capable of scanning hundreds of cameras every minute. The system is operating around the clock in Southern California and has already detected some fires earlier than the current best methods—people calling emergency agencies or satellite detection from the Geostationary Operational Environmental Satellite (GOES) satellites. This system is already better than some commercial systems and there are still many unexplored methods to further improve accuracy. Ground-based cameras are not going to be able to detect every wildfire, and so we are building a system that combines the best of terrestrial camera-based detection with the best approaches to satellite-based detection.
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- 2020
4. Analysis of electrocardiographic intervals before and after transcatheter aortic valve implantation to predict the need for permanent pacing
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Timothy Ball, Peter A. McCullough, Manish D. Assar, Robert C. Stoler, Jong Mi Ko, and Anupama Vasudevan
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medicine.medical_specialty ,Transcatheter aortic ,Heart block ,business.industry ,Area under the curve ,Original Articles ,General Medicine ,030204 cardiovascular system & hematology ,medicine.disease ,03 medical and health sciences ,QRS complex ,0302 clinical medicine ,Baseline characteristics ,Internal medicine ,Cardiology ,medicine ,030212 general & internal medicine ,Permanent pacemaker ,Electrical conduction system of the heart ,Complication ,business - Abstract
Transcatheter aortic valve implantation (TAVI) is growing in utilization in the USA, and atrioventricular heart block is a common complication of the procedure. In patients with conduction system changes following TAVI, there are no clear guidelines for permanent pacing, leading to difficult clinical decisions on how long to leave temporary transvenous pacemakers in place. The aim of our study was to determine whether changes in electrocardiogram characteristics could predict the need for permanent pacing. A retrospective analysis was conducted of 209 consecutive TAVI patients seen from January 2012 to December 2015 at Baylor Heart and Vascular Hospital, Dallas. The baseline characteristics were similar between those who received a permanent pacemaker (PPM) within 7 days of the procedure (21.1%) and those who did not (78.9%); of those who did receive a PPM, 79.5% were implanted for complete heart block. The median (range) percentage change in the sum of QRS and PR was significantly higher in those who received a PPM (20.2%) than those who did not (7.1%) (P = 0.004). Using the percentage change in the sum of QRS and PR to predict PPM, the area under the curve was found to be 0.69. The optimal cutpoint was found to be 18.9% (sensitivity = 0.63, specificity = 0.73). Our study suggests that delay in the conduction system immediately following TAVI predicts the need for permanent pacing.
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- 2018
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5. Management of neutropenic fever in a private hospital oncology unit
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Eli Gabbay, Astrid Arellano, Rohen Skiba, Timothy Ball, Timothy D. Clay, and Nisha Sikotra
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Oncology ,medicine.medical_specialty ,Neutropenia ,Fever ,medicine.drug_class ,medicine.medical_treatment ,Antibiotics ,030204 cardiovascular system & hematology ,Malignancy ,Hospitals, Private ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Neoplasms ,Internal Medicine ,Medicine ,Humans ,030212 general & internal medicine ,Retrospective Studies ,Chemotherapy ,business.industry ,Medical record ,Neutropenic fever ,Australia ,Retrospective cohort study ,Middle Aged ,medicine.disease ,Anti-Bacterial Agents ,Female ,business ,Febrile neutropenia - Abstract
AIM: Febrile neutropenia is a medical emergency, which poses a significant morbidity and mortality risk to cancer patients receiving chemotherapy. National guidelines recommend that patients presenting with suspected febrile neutropenia receive appropriate intravenous antibiotics within 60 min of admission. We aimed to investigate the management of febrile neutropenia in a large private oncology centre. METHOD: A retrospective audit of all patients who presented to St John of God Hospital, Subiaco in the 2017 calendar year, with a known solid organ malignancy and a recorded diagnosis of febrile neutropenia. Patients were identified through the hospitals Patient Administration System and ICD-10 codes. Information was collected from the hospital medical records using a standardised data collection tool. RESULTS: There were 98 admissions relating to 88 patients with febrile neutropenia during the study period. The median age was 64 years (range: 23-85 years) with 57 (65%) females. Antibiotic selections consistent with the Australian guidelines were made in 88 admissions (89%). The mean time to antibiotic administration was 279 min, with a median of 135 min (range: 15-5160 min). Antibiotics were administered within the recommended time frame in only eight (11%) admissions. CONCLUSION: Clinicians prescribed antibiotics in accordance with national guidelines, however there were systemic inefficiencies which resulting in delayed antibiotic initiation. This has resulted in implementation of strategies to minimise delay. This article is protected by copyright. All rights reserved.
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- 2019
6. Evaluating Blood Loss and the Effect of Antiplatelet Treatment in Foot and Ankle Amputations
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J. Randolph Clements, Jonathon J. Carmouche, Daniel C. Jupiter, Timothy Ball, and David Schweer
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Blood Loss, Surgical ,030204 cardiovascular system & hematology ,Hematocrit ,Amputation, Surgical ,03 medical and health sciences ,0302 clinical medicine ,Diabetes mellitus ,Humans ,Medicine ,Blood Transfusion ,Orthopedics and Sports Medicine ,cardiovascular diseases ,030212 general & internal medicine ,Aged ,Retrospective Studies ,Aspirin ,medicine.diagnostic_test ,Foot ,business.industry ,Perioperative ,Middle Aged ,Clopidogrel ,medicine.disease ,Surgery ,medicine.anatomical_structure ,Amputation ,Hemostasis ,Female ,Ankle ,business ,Platelet Aggregation Inhibitors ,circulatory and respiratory physiology ,medicine.drug - Abstract
The interrelationship between diabetes mellitus and cardiovascular disease is well-documented, and, secondary to the latter, is the use of antiplatelet therapy. Although diabetes and the associated vascular manifestations are driving forces behind lower extremity amputations, few data are available on the risks of perioperative antiplatelet therapy with foot and ankle amputations. The goal of the present study was to address the surgical effect of continuing or discontinuing antiplatelet therapy before foot and/or ankle amputation. The following data were retrospectively collected: blood loss, pre- and postoperative hematocrit and hemoglobin, operative time, amputation type, age, diabetic status, antiplatelet treatment, and number of transfusions during the perioperative period. Perioperative antiplatelet therapy was defined as exposure to aspirin or clopidogrel within 3 days before surgery. To compare the outcomes between groups, the following factors were analyzed using bivariate analyses and then multivariate regression models: (1) the need for transfusions, (2) high blood loss (>20 mL), (3) volume of blood loss, and (4) operative time. The noninferiority of continued antiplatelet use was assessed in terms of operative time and blood loss, using a noninferiority margin of 10 minutes or 10 mL, respectively. Antiplatelet therapy was not a statistically significant risk factor for any of the studied outcomes on multivariate analysis. Equivalence testing revealed that continuing antiplatelet therapy is not inferior to discontinuing perioperative therapy in terms of blood loss and operative time. Multivariate analysis of the data suggested that antiplatelet therapy has no statistically significant impact on blood loss, transfusion rate, or operative time.
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- 2016
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7. 1934 Atrioesophegeal Fistula, a Rare but Devastating Cause of Upper Gastrointentinal Bleeding
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Vishal Kaila, Timothy Ball, Rajeev Jain, Jay Franklin, Beth Frost, Jeffrey Barnard, and Manish D. Assar
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medicine.medical_specialty ,Hepatology ,business.industry ,Fistula ,Gastroenterology ,Medicine ,business ,medicine.disease ,Surgery - Published
- 2019
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8. Chronic Pulmonary Embolism in a Young Athletic Woman
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Timothy Ball and Timothy R. Larsen
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medicine.medical_specialty ,Chronic pulmonary embolism ,biology ,business.industry ,Athletes ,General Medicine ,030204 cardiovascular system & hematology ,Exertional dyspnea ,medicine.disease ,biology.organism_classification ,Bronchospasm ,Surgery ,Hypoxemia ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Cardiology ,Etiology ,Pulmonary Trunk ,030212 general & internal medicine ,medicine.symptom ,Thrombus ,business - Abstract
Exercise-induced dyspnea (EID) is a common complaint in young athletes. Exercise-induced bronchospasm (EIB) is the most common cause of EID in healthy athletes, but it is important to recognize more serious pathology. Herein we present the case of an 18-year-old woman with a 1.5-year history of EID. She had been treated for EIB without relief. Her arterial oxygen saturation was 88% during exercise testing. Computed tomographic angiography to assess for vascular abnormalities identified a large thrombus in the main pulmonary trunk. Symptoms markedly improved with therapeutic anticoagulation. Massive pulmonary embolus is an exceedingly rare etiology of exertional dyspnea in young athletes. Hypoxemia during exercise testing was an important clue that something more ominous was lurking that required definitive diagnosis.
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- 2015
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9. Utility of Indium-111 Octreotide to Identify a Cardiac Metastasis of a Carcinoid Neoplasm
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Mohammed A. Farooqui, Timothy Ball, and Sulaiman Rathore
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endocrine system ,Pathology ,medicine.medical_specialty ,endocrine system diseases ,Carcinoid tumors ,Octreotide ,030204 cardiovascular system & hematology ,03 medical and health sciences ,Case Studies ,0302 clinical medicine ,Biopsy ,medicine ,Carcinoid Heart Disease ,Neoplasm ,030212 general & internal medicine ,neoplasms ,medicine.diagnostic_test ,business.industry ,Octreotide scan ,Myxoma ,General Medicine ,medicine.disease ,digestive system diseases ,medicine.anatomical_structure ,Ventricle ,cardiovascular system ,business ,medicine.drug - Abstract
Carcinoid heart disease is classically described as right-sided valvular pathology. Solid cardiac metastases from carcinoid tumors are seldom reported. A multimodality imaging approach is needed to diagnose and localize this disease. Biopsy remains the gold standard to confirm the diagnosis of carcinoid. Octreotide uptake is characteristic of carcinoid tumor but not myxoma; thus, an indium-111 octreotide scan is very specific for the diagnosis of carcinoid tumor and helps in assessing the extent of carcinoid disease. We present a case in which an indium-111 octreotide scan revealed uptake in three distinct masses in the colon, liver, and right ventricle. The results of the scan were contradictory to the biopsy results, which were diagnostic for hepatic carcinoid and cardiac myxoma.
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- 2016
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10. Contents Vol. 127, 2014
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Dianne B. McKay, Benjamin D. Humphreys, Sanjeev Noel, Michael Heung, Paul W. Sanders, Joseph C. Gigliotti, Maria N. Martina-Lingua, Sashi G. Kasimsetty, Lakhmir S. Chawla, Kathleen D. Liu, S. Noel, Antoine G. Schneider, Can Ince, Zheng Dong, Peter A. McCullough, Timothy Ball, Raghavan Murugan, Hamid Rabb, Zoltan H. Endre, Etienne Macedo, Isaah S. Vincent, Liyu He, Stuart L. Goldstein, Didier Portilla, Rosalinde Masereeuw, Emaad M. Abdel-Rahman, Peter Pickkers, Daniel A. Peterson, A.R.A. Hamad, Nattachai Srisawat, Monica Zanella, Andrew D. Shaw, Hyun-Joon Shin, Kelly K. Andringa, Satz Mengensatzproduktion, Francesco Garzotto, Susanne V. Fleig, Samatha Bandapalle, Anupam Agarwal, Prasad Devarajan, Aashish Sharma, Esther Peters, Jennifer L. Pluznick, Sean M. Bagshaw, Volker Vallon, Mark D. Okusa, Claudio Ronco, Druckerei Stückle, Richard A. Zager, Man J. Livingston, Sean E. DeWolf, Ravindra L. Mehta, H. Rabb, John A. Kellum, Abdel Rahim A. Hamad, Mélanie Godin, Alana A. Shigeoka, Joseph V. Bonventre, Aneley Hundae, Marìa Jimena Mucino, Patrick T. Murray, Samir M. Parikh, Prabhleen Singh, Noureddin Nourbakhsh, S. Bandapalle, Mei Tran, Frederic T. Billings, M.N. Martina, and Ali C.M. Johnson
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Nephrology ,business.industry ,Physiology ,Medicine ,General Medicine ,business - Published
- 2014
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11. Chronic Anticoagulation in Chronic Kidney Disease∗
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Peter A. McCullough, Kevin R. Wheelan, and Timothy Ball
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Male ,medicine.medical_specialty ,CHA2DS2-VASc score ,Disease ,arrhythmia ,Internal medicine ,Atrial Fibrillation ,Humans ,Medicine ,In patient ,Renal Insufficiency, Chronic ,business.industry ,Warfarin ,Anticoagulants ,Atrial fibrillation ,medicine.disease ,warfarin ,Stroke ,Bright Disease ,CHA2DS2–VASc score ,Cardiology ,Female ,thromboprophylaxis ,Cardiology and Cardiovascular Medicine ,business ,Complication ,chronic kidney disease ,Kidney disease ,medicine.drug - Abstract
Bleeding in patients with chronic kidney disease (CKD) or “uremic bleeding” is a well-recognized complication. It has been described as far back as 1907 by Reisman [(1)][1], classically as a complication of Bright disease. The continued debate over the mechanism of this disease only highlights
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- 2014
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12. Use of Oral Anticoagulation in the Management of Atrial Fibrillation in Patients with ESRD: Pro
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Katy Mathews Cox, Manish D. Assar, Peter A. McCullough, and Timothy Ball
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medicine.medical_specialty ,Epidemiology ,Pyridones ,Controversies in Nephrology ,Management of atrial fibrillation ,Administration, Oral ,Hemorrhage ,030204 cardiovascular system & hematology ,Critical Care and Intensive Care Medicine ,End stage renal disease ,Dabigatran ,03 medical and health sciences ,0302 clinical medicine ,Rivaroxaban ,Internal medicine ,Commentaries ,Atrial Fibrillation ,Medicine ,Humans ,cardiovascular diseases ,030212 general & internal medicine ,Stroke ,Transplantation ,business.industry ,Patient Selection ,Hazard ratio ,Warfarin ,Anticoagulants ,Atrial fibrillation ,medicine.disease ,Nephrology ,Cardiology ,Kidney Failure, Chronic ,Pyrazoles ,business ,medicine.drug - Abstract
Warfarin has had a thin margin of benefit over risk for the prevention of stroke and systemic embolism in patients with ESRD because of higher bleeding risks and complications of therapy. The successful use of warfarin has been dependent on the selection of patients with nonvalvular atrial fibrillation at relatively high risk of stroke and systemic embolism and lower risks of bleeding over the course of therapy. Without such selection strategies, broad use of warfarin has not proven to be beneficial to the broad population of patients with ESRD and nonvalvular atrial fibrillation. In a recent meta-analysis of use of warfarin in patients with nonvalvular atrial fibrillation and ESRD, warfarin had no effect on the risks of stroke (hazard ratio, 1.12; 95% confidence interval, 0.69 to 1.82; P=0.65) or mortality (hazard ratio, 0.96; 95% confidence interval, 0.81 to 1.13; P=0.60) but was associated with increased risk of major bleeding (hazard ratio, 1.30; 95% confidence interval, 1.08 to 1.56; P
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- 2016
13. Late Complication
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Aaron V. Kaplan, Renu Virmani, Jason R. Foerst, Masataka Nakano, and Timothy Ball
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Coronary angiography ,medicine.medical_specialty ,business.industry ,Unstable angina ,medicine.medical_treatment ,Late complication ,Stent ,Morbidly obese ,medicine.disease ,Surgery ,Restenosis ,Internal medicine ,medicine ,Cardiology ,cardiovascular diseases ,Circumflex ,Distal right coronary artery ,business ,Cardiology and Cardiovascular Medicine - Abstract
A 70-year-old morbidly obese woman with severe emphysema presented with unstable angina. Coronary angiography revealed high-grade, calcified, ostial left circumflex (LCX) and distal right coronary artery (RCA) lesions. She was deemed a high-risk surgical candidate and underwent stenting of the left
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- 2012
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14. Use of the venture catheter to shorten the door-to-balloon time in patients with ST-Segment elevation acute myocardial infarction
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Timothy Ball, Emmanouil S. Brilakis, and Subhash Banerjee
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Male ,Cardiac Catheterization ,medicine.medical_specialty ,Catheters ,Time Factors ,medicine.medical_treatment ,Myocardial Infarction ,Coronary Angiography ,Electrocardiography ,Internal medicine ,medicine ,Humans ,ST segment ,Myocardial infarction ,Angioplasty, Balloon, Coronary ,Aged ,Thrombectomy ,business.industry ,Coronary Thrombosis ,Percutaneous coronary intervention ,Electrocardiography in myocardial infarction ,Drug-Eluting Stents ,Equipment Design ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,Catheter ,Treatment Outcome ,Coronary Occlusion ,Coronary occlusion ,Conventional PCI ,Cardiology ,Door-to-balloon ,Cardiology and Cardiovascular Medicine ,business - Abstract
Achieving a door-to-balloon time
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- 2011
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15. Professor Fred Singer: Champion of Science, Because Nothing Less than the Truth Was Adequate
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Timothy Ball
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geography ,Environmental Engineering ,geography.geographical_feature_category ,Renewable Energy, Sustainability and the Environment ,media_common.quotation_subject ,Fell ,Champion ,Energy Engineering and Power Technology ,Environmental ethics ,Revelation ,Silence ,Politics ,Lawsuit ,Nothing ,Political science ,Law ,Energy (miscellaneous) ,Courage ,media_common - Abstract
Professor Fred Singer is a scientist practicing science correctly. He became a leader in society because, in doing that, he ran headlong into groups and governments distorting science for political reasons. As Voltaire said, “It is dangerous to be right in matters on which the established authorities are wrong.” Sadly, few can relate to the courage it takes to pursue the truth and the price Fred paid and continues to pay. I know because I experienced the same vindictive, fallacious personal attacks including law suits apparently designed to silence rather than expose the truth. It was the reason I was so proud and humbled to share a keynote speaker role with Fred at the first Heartland Climate Conference in New York. Before the Heartland lunch Fred asked how I was doing. I told him I received a lawsuit. He immediately identified the lawyer’s name. I was surprised until he explained that he and others had received similar lawsuits from the same person. The revelation hardened my resolve to fight, even though I had surrendered to previous legal threats. Fred has uncovered a changing pattern of science and education that is more disturbing in the long run. Traditionally young people came into education challenging and questioning the prevailing wisdoms. Now most young people enter university fully indoctrinated and accept existing scientific doctrines without question. Challenges to the prevailing wisdoms fell to the older scientists. Those seeking facts, without which science cannot function, are marginalized or confronted by people concerned with dogma. This reflects another very disturbing change in science and society in the last few decades. Farad Manjoo identified the pattern in his book True Enough; Learning to Live in a Post-fact Society. A synopsis explains
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- 2014
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16. Climate Change: Dangers of a Singular Approach and Consideration of a Sensible Strategy
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Timothy Ball
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Environmental Engineering ,Renewable Energy, Sustainability and the Environment ,Climatology ,Global warming ,Energy Engineering and Power Technology ,Ecological forecasting ,Climate change ,Environmental science ,Adaptation (computer science) ,Energy (miscellaneous) - Abstract
The Intergovernmental Panel on Climate Change (IPCC) has convinced many, including most governments, that the only future is global warming. IPCC's structure and directions required it only examine human causes of climate change. It also created a view that warming was only disastrous. Actually, there are more benefits to warming than cooling. Evidence indicates cooling is already occurring, because of changes in solar activity. Cooling is much more problematic. A logical strategy regardless of the trend is to prepare for cooling. Adaptation to warming is easier than to cooling.
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- 2009
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17. Time and Cost Saving Strategies for Water Pipe Lining Operations
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R. Timothy Ball and Thomas D. Rockaway
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Engineering ,business.industry ,media_common.quotation_subject ,Benchmarking ,Scheduling (computing) ,Cost savings ,Task (project management) ,Risk analysis (engineering) ,Service (economics) ,Cost control ,Water pipe ,Statistical analysis ,Operations management ,business ,Civil and Structural Engineering ,media_common - Abstract
Repair and maintenance of existing distribution lines is an increasing concern for water utilities. While pipe lining activities are effective and generally less expensive than complete replacement, they still represent considerable time and expense. This study provides guidance on the best practices to minimize the amount of time that customers are without water service, must endure restricted service, or are served by less secure networks due to pipe lining activities. Nine utilities provided benchmarking data to identify efficient operations. Statistical analysis indicates that minor changes to task sequencing and materials may improve efficiencies by several hours to several days. However, in order to obtain a rapid lining operation, utilities must promote extensive changes to pipe lining philosophy and to the disinfectant approach. While a rapid disinfectant approach (less than 24 h ) is not typically adopted by United States utilities, preliminary testing indicates that addressing the newly lined pi...
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- 2008
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18. Usefulness of percutaneous closure of patent foramen ovale for hypoxia
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Timothy Ball, Alyssa G. Munkres, Shelley A. Hall, Themistokles Chamogeorgakis, James W. Choi, and Kenneth A. Ausloos
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Aortic dissection ,Marfan syndrome ,medicine.medical_specialty ,Percutaneous ,business.industry ,Aortic root ,General Medicine ,030204 cardiovascular system & hematology ,Hypoxia (medical) ,medicine.disease ,Shunt (medical) ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,Case Studies ,stomatognathic system ,Patent foramen ovale ,medicine ,030212 general & internal medicine ,medicine.symptom ,business - Abstract
We report a patient with hypoxia secondary to a right-to-left shunt through a patent foramen ovale, following aortic root, valve, and arch replacement due to an aortic dissection in the setting of the Marfan syndrome. Following the operation, he failed extubation twice due to hypoxia. An extensive workup revealed a right-to-left shunt previously not seen. The patent foramen ovale was closed using a percutaneous closure device. Following closure, our patient was extubated without difficulty and has done well postoperatively.
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- 2015
19. RATES OF MECHANICAL VALVE THROMBOSIS AFTER DISCONTINUATION OF ANTICOAGULATION
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Timothy Ball, Onyedika J. Ilonze, and Pratik Kanabur
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medicine.medical_specialty ,business.industry ,medicine ,Cardiology and Cardiovascular Medicine ,medicine.disease ,business ,Thrombosis ,Mechanical valve ,Surgery ,Discontinuation - Published
- 2017
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20. Statins for the prevention of contrast-induced acute kidney injury
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Peter A. McCullough and Timothy Ball
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Acute coronary syndrome ,medicine.medical_specialty ,Statin ,medicine.drug_class ,medicine.medical_treatment ,Lipoproteins ,Contrast Media ,urologic and male genital diseases ,Coronary Angiography ,Rhabdomyolysis ,Diabetes Complications ,Percutaneous Coronary Intervention ,Meta-Analysis as Topic ,Internal medicine ,medicine ,Albuminuria ,Humans ,Rosuvastatin ,Renal replacement therapy ,Acute Coronary Syndrome ,Renal Insufficiency, Chronic ,Rosuvastatin Calcium ,Randomized Controlled Trials as Topic ,Muscle Cells ,Sulfonamides ,urogenital system ,business.industry ,Acute kidney injury ,Percutaneous coronary intervention ,General Medicine ,Acute Kidney Injury ,medicine.disease ,female genital diseases and pregnancy complications ,Fluorobenzenes ,Renal Replacement Therapy ,Kidney Tubules ,Pyrimidines ,Nephrology ,Creatinine ,Inactivation, Metabolic ,Cardiology ,medicine.symptom ,Hydroxymethylglutaryl-CoA Reductase Inhibitors ,business ,Kidney disease ,medicine.drug - Abstract
Acute kidney injury (AKI) is a common medical problem, especially in patients undergoing cardiovascular procedures. The risk of kidney damage has multiple determinants and is often related to or exacerbated by intravenous or intra-arterial iodinated contrast. Contrast-induced AKI (CI-AKI) has been associated with an increased risk of subsequent myocardial infarction, stroke, the development of heart failure, rehospitalization, progression of chronic kidney disease, end-stage renal disease, and death. Statins have been studied extensively in the setting of chronic kidney disease and they have been shown to reduce albuminuria, but they have had no effect on the progressive reduction of glomerular filtration or the need for renal replacement therapy. Several meta-analyses have shown a protective effect of short-term statin administration on CI-AKI and led to two large randomized controlled trials evaluating the role of rosuvastatin in the prevention of CI-AKI in high-risk patients with acute coronary syndrome and diabetes mellitus. Both trials showed a benefit of rosuvastatin prior to contrast administration in a statin-naive patient population. In aggregate, these studies support the short-term use of statins specifically for the prevention of CI-AKI in patients undergoing coronary angiography with or without percutaneous coronary intervention.
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- 2014
21. Radial artery pseudoaneurysm: a simplified treatment method
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Timothy Ball, Paul M. Robb, Matthew Cauchi, and Robert P. Zemple
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Arterial cannulation ,Pseudoaneurysm ,medicine.artery ,Compression Bandages ,Occlusion ,Pressure ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Oximetry ,Radial artery ,Ultrasonography, Doppler, Color ,Cardiac catheterization ,Radiological and Ultrasound Technology ,business.industry ,Treatment options ,Treatment method ,Middle Aged ,medicine.disease ,Doppler sonography ,Treatment Outcome ,Radial Artery ,cardiovascular system ,Radiology ,business ,Aneurysm, False - Abstract
A radial artery pseudoaneurysm represents a rare, potentially catastrophic complication of arterial cannulation that has been reported after cardiac catheterization. Treatment options are limited to chemical, mechanical, and combined approaches to obliterate the radial artery pseudoaneurysm and tract. Manual compression protocols using the TR Band (Terumo Medical Corporation, Somerset, NJ) have been variable and anecdotal, without objective measurements of adequate compression, making this technique prone to failure. In this report, we present an efficient, safe, and noninvasive management protocol using a pulse oximeter and the TR Band for treatment of radial artery pseudoaneurysms that is cost-effective and efficient and ensures correction without occlusion of the radial artery.
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- 2014
22. Carbon budgeting in plant-soil mesocosms under elevated CO2 : locally missing carbon?
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Yiqi Luo, Dale W. Johnson, Weixin Cheng, Daniel A. Sims, James S. Coleman, and J. Timothy Ball
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Total organic carbon ,Global and Planetary Change ,Ecology ,Carbon-13 ,Biomass ,Primary production ,chemistry.chemical_element ,Photosynthesis ,Mesocosm ,chemistry ,Environmental chemistry ,Botany ,Respiration ,Environmental Chemistry ,Environmental science ,Carbon ,General Environmental Science - Abstract
Summary Studies have suggested that more carbon is fixed due to a large increase in photosynthesis in plant–soil systems exposed to elevated CO2 than could subsequently be found in plant biomass and soils –- the locally missing carbon phenomenon. To further understand this phenomenon, an experiment was carried out using EcoCELLs which are open-flow, mass-balance systems at the mesocosm scale. Naturally occurring 13C tracers were also used to separately measure plant-derived carbon and soil-derived carbon. The experiment included two EcoCELLs, one under ambient atmospheric CO2 and the other under elevated CO2 (ambient plus 350 μL L− 1). By matching carbon fluxes with carbon pools, the issue of locally missing carbon was investigated. Flux-based net primary production (NPPf) was similar to pool-based primary production (NPPp) under ambient CO2, and the discrepancy between the two carbon budgets (12 g C m− 2, or 4% of NPPf) was less than measurement errors. Therefore, virtually all carbon entering the system under ambient CO2 was accounted for at the end of the experiment. Under elevated CO2, however, the amount of NPPf was much higher than NPPp, resulting in missing carbon of approximately 80 g C m− 2 or 19% of NPPf which was much higher than measurement errors. This was additional to the 96% increase in rhizosphere respiration and the 50% increase in root growth, two important components of locally missing carbon. The mystery of locally missing carbon under elevated CO2 remains to be further investigated. Volatile organic carbon, carbon loss due to root washing, and measurement errors are discussed as some of the potential contributing factors.
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- 2000
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23. The photosynthesis - leaf nitrogen relationship at ambient and elevated atmospheric carbon dioxide: a meta-analysis
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Ana Rey, Richard J. Norby, Andrew G. Peterson, Peter S. Curtis, David T. Tissue, Yiqi Luo, Christopher B. Field, Peter B. Reich, Carla A. Gunderson, Cmeal Participants, Kevin L. Griffin, M. Forstreuter, Christoph S. Vogel, and J. Timothy Ball
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Global and Planetary Change ,Carbon dioxide in Earth's atmosphere ,Ecology ,chemistry.chemical_element ,Atmospheric sciences ,Nitrogen ,chemistry.chemical_compound ,Deciduous ,chemistry ,Content (measure theory) ,Vegetation type ,Botany ,Carbon dioxide ,Environmental Chemistry ,Environmental science ,Ecosystem ,Nitrogen cycle ,General Environmental Science - Abstract
Estimation of leaf photosynthetic rate (A) from leaf nitrogen content (N) is both conceptually and numerically important in models of plant, ecosystem and biosphere responses to global change. The relationship between A and N has been studied extensively at ambient CO{sub 2} but much less at elevated CO{sub 2}. This study was designed to (1) assess whether the A-N relationship was more similar for species within than between community and vegetation types, and (2) examine how growth at elevated CO{sub 2} affects the A-N relationship. Data were obtained for 39 C{sub 3} species grown at ambient CO{sub 2} and 10 C{sub 3} species grown at ambient and elevated CO{sub 2}. A regression model was applied to each species as well as to species pooled within different community and vegetation types. Cluster analysis of the regression coefficients indicated that species measured at ambient CO{sub 2} did not separate into distinct groups matching community or vegetation type. Instead, most community and vegetation types shared the same general parameter space for regression coefficients. Growth at elevated CO{sub 2} increased photosynthetic nitrogen use efficiency for pines and deciduous trees. When species were pooled by vegetation type, the A-N relationship for deciduous trees expressed onmore » a leaf-mass bask was not altered by elevated CO{sub 2}, while the intercept increased for pines. When regression coefficients were averaged to give mean responses for different vegetation types, elevated CO{sub 2} increased the intercept and the slope for deciduous trees but increased only the intercept for pines. There were no statistical differences between the pines and deciduous trees for the effect of CO{sub 2}. Generalizations about the effect of elevated CO{sub 2} on the A-N relationship, and differences between pines and deciduous trees will be enhanced as more data become available.« less
- Published
- 1999
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- View/download PDF
24. Ball State Symphony Orchestra [and] Chamber & Concert Choirs [with] undergraduate solo/concerto competition winner
- Author
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Ball State University. Symphony Orchestra; Droste, Douglas; Lewis, Timothy; Ball State University. Chamber Choir; Ball State University. Concert Choir; Crow, Andrew; Glann, Kerry; Sosenheimer, Briana; Walker, Lauren; Salmon, Ganson; Yu, Zhenghuan; Park, Areum; McNamara, Joseph, Ball State University. School of Music, Ball State University. Symphony Orchestra; Droste, Douglas; Lewis, Timothy; Ball State University. Chamber Choir; Ball State University. Concert Choir; Crow, Andrew; Glann, Kerry; Sosenheimer, Briana; Walker, Lauren; Salmon, Ganson; Yu, Zhenghuan; Park, Areum; McNamara, Joseph, and Ball State University. School of Music
- Abstract
With the Ball State Symphony Orchestra, Timothy Lewis, piano, the Ball State Chamber Choir, the Ball State Concert Choir, Briana Sosenheimer, soprano, Lauren Walker, mezzo-soprano, Ganson Salmon, tenor, Zhenghuan Yu, bass.; Conductors: Douglas Droste, Andrew Crow, Kerry Glann.; Includes a list of the personnel of the Orchestra and an undifferentiated list of the personnel of the Choirs.; Includes program notes about both pieces.; Includes the text for Mozart's Requiem Mass in D minor (KV 626), translated from the original Latin into English.; Includes biographical information about pianist & student Timothy Lewis (with a color portrait photograph).; Includes a list of the administration, staff, & faculty relevant to the performers.; Includes a list of future orchestral & choral events (for March 2015-April 2015)., Series LXIX, Number 138., This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about
- Published
- 2015
25. Percutaneous coronary intervention and the management of acute coronary syndromes in patients with von Willebrand disease
- Author
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Sulaiman, Rathore, Dexter, Deleon, Hafsa, Akram, David, Sane, and Timothy, Ball
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von Willebrand Diseases ,Percutaneous Coronary Intervention ,Treatment Outcome ,Fibrinolytic Agents ,Patient Education as Topic ,Disease Management ,Humans ,Drug Therapy, Combination ,Female ,Comorbidity ,Acute Coronary Syndrome ,Middle Aged ,Platelet Aggregation Inhibitors - Abstract
Von Willebrand disease (vWD) results from quantitative or qualitative deficiency of von Willebrand factor (vWF). The occurrence of myocardial infarction is very rare in patients with vWD. A few case reports of acute coronary syndrome (ACS) in vWD patients are present in the literature, but no definite management recommendations are available for such patients.We report a case of successful percutaneous coronary intervention (PCI) with bare-metal stent (BMS) implantation in a 46-year-old woman with type 1 vWD and history of coronary artery disease (CAD). She received periprocedural dual-antiplatelet therapy for 2 weeks and then continued aspirin without any bleeding complications.The optimal management of patients with vWD and ACS is complex and presents a therapeutic challenge. We propose that dual-antiplatelet therapy can be used safely in most vWD patients presenting with ACS as most of them are type 1 vWD. PCI with BMS can be done safely. Long-term management of these patients requires a systemic approach including hematological consultation, ascertaining vWF levels, as well as patient education and close outpatient follow-up.
- Published
- 2013
26. Effects of elevated CO2 and nitrogen on the synchrony of shoot and root growth in ponderosa pine
- Author
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David T. Tingey, Dale W. Johnson, Donald L. Phillips, J. Timothy Ball, and Mark Johnson
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Root growth ,%22">Pinus ,Animal science ,Human fertilization ,Physiology ,Chemistry ,Shoot ,Botany ,chemistry.chemical_element ,Plant Science ,Leaf area index ,Nitrogen ,Ambient air - Abstract
We monitored effects of elevated CO(2) and N fertilization on shoot and fine root growth of Pinus ponderosa Dougl. ex P. Laws. and C. Laws. grown in native soil in open-top field-exposure chambers at Placerville, CA, over a 2-year period. The experimental design was a replicated 3 x 3 factorial with the center treatment missing; plants were exposed to ambient (~365 micro mol mol(-1)) air or ambient air plus either 175 or 350 micro mol mol(-1) CO(2) in combination with one of three rates of N addition (0, 100 or 200 kg ha(-1) year(-1)). All CO(2) by N interactions were nonsignificant. Both the CO(2) and N treatments increased plant height, stem diameter and leaf area index (LAI). Elevated CO(2) increased fine root area density and the occurrence of mycorrhizae, whereas N fertilization increased coarse root area density but had no effect on fine root area density. Spring flushes of shoot height and diameter growth were initiated concurrently with the increase in new root area density but height and diameter growth reached their maxima before that of fine roots. The temporal patterns of root and shoot growth were not altered by providing additional CO(2) or N. Greatest root loss occurred in the summer, immediately following the period of greatest new fine root growth. Elevated N initially reduced the fine root area density/LAI ratio independently of CO(2) treatment, indicating that the relationship between fine roots and needles was not changed by CO(2) exposure.
- Published
- 1996
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27. Sensitivity of leaf photosynthesis to CO2concentration is an invariant function for C3plants: A test with experimental data and global applications
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Richard B. Thomas, J. Timothy Ball, David T. Tissue, Yiqi Luo, and Daniel A. Sims
- Subjects
Atmospheric Science ,Global and Planetary Change ,Environmental factor ,chemistry.chemical_element ,Biology ,Photosynthesis ,medicine.disease_cause ,Photosynthetic capacity ,Nitrogen ,Acclimatization ,Horticulture ,chemistry.chemical_compound ,chemistry ,Photosynthetic acclimation ,Botany ,Carbon dioxide ,medicine ,Environmental Chemistry ,Terrestrial ecosystem ,General Environmental Science - Abstract
Rising atmospheric CO2 concentration (Ca) may alter two components (sensitivity and acclimation) of global photosynthetic carbon influx into terrestrial ecosystems (P G). Most existing global models focus on long-term acclimation. We have developed a leaf-level function ( ;e) to quantify short-term increment of p G associated with sensitivity .The ;e function is the normalized response of leaf photosynthesis to a small change in C" and has been suggested to be an invariant function for C3 plants grown in diverse environments. This paper tests the hypothesis that" ;;£ is an invariant function. We calculated values of;e from 9 sets of experimental data which incorporated photosynthetic responses of 12 plant species to measurement conditions of light and temperature and to growth in different light, temperature, nitrogen, phosphorus, water stress, and CO2 concentration. Absolute rates of leaf photosynthesis differed by more than tenfold due to species differences and environmental variation. However, ;e values derived from these data sets converged into a narrow range defined by two equations of the;£ function, confirming that ;e was insensitive to differences in photosynthetic capacity among species and between plants acclimated to different growth environments. Using the;£ function, we predict that a yearly increase of 1.5 parts per million (ppm) in Ca will induce an increase in PG by 0.18 to 0.34 Gt (1 Gt = 1015 g) C yr-1 in 1993, provided that (1) PG = 120 Gt C yr', (2) 85% of PG is generated by c3 plant assimilation, and (3) the 1.5-ppm increase in CQ will not induce significant photosynthetic acclimation.
- Published
- 1996
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28. Stem maintenance and construction respiration in Pinus ponderosa grown in different concentrations of atmospheric CO2
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Evan H. DeLucia, Eileen V. Carey, and J. Timothy Ball
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Maintenance respiration ,Aboveground carbon ,Tissue respiration ,Physiology ,Chemistry ,chemistry.chemical_element ,Plant Science ,%22">Pinus ,Animal science ,Respiration ,Relative growth rate ,Botany ,Respiration rate ,Carbon - Abstract
To determine whether long-term growth in enriched CO(2) atmospheres changes the woody tissue respiration component of aboveground carbon budgets, we measured woody tissue respiration of stems of 3-year-old ponderosa pine (Pinus ponderosa Laws.) grown in ambient (350 ppm) or twice ambient (700 ppm) atmospheric CO(2) concentrations in open-top field chambers located in Placerville, CA. Total respiration rate was measured by gas exchange, and construction respiration was calculated from the construction cost, percent carbon of stem samples and relative growth rate. Maintenance respiration was determined as the difference between total and construction respiration. The Q(10) of respiration was greater in stems grown in elevated CO(2) than in stems grown in ambient CO(2) (2.20 versus 1.67). As a result, mean daily respiration per unit volume of wood modeled for the month of September was greater in trees growing in elevated CO(2) than in ambient CO(2) (46.75 versus 40.45 mol m(-3) day(-1)). These effects of atmospheric CO(2) concentration were not the result of differences in relative growth rate. Calorimetric analyses of woody tissue construction cost indicated no difference between treatments; however, trees in the elevated CO(2) treatment showed a 1% lower carbon concentration than trees in the ambient CO(2) treatment. Estimates of construction respiration did not differ between treatments, confirming that the treatment differences in mean daily respiration rate were attributable to the maintenance component. Under future predicted atmospheric conditions, changes in the maintenance respiration of woody tissue may lead to an increase in the respiration component of whole-plant carbon budgets of ponderosa pine. Our results suggest that potential increases in the maintenance component of stem respiration should be considered when modeling the response of forest stand growth to enriched CO(2) atmospheres.
- Published
- 1996
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29. Lessons from Lysimeters: Soil N Release from Disturbance Compromises Controlled Environment Study
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J. Timothy Ball, Roger F. Walker, and Dale W. Johnson
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Ecology ,fungi ,technology, industry, and agriculture ,food and beverages ,Environment controlled ,chemistry.chemical_element ,Mineralization (soil science) ,complex mixtures ,Nitrogen ,Potting ,chemistry.chemical_compound ,Human fertilization ,chemistry ,Lysimeter ,Carbon dioxide ,Environmental science ,Nitrification - Abstract
A controlled environment study of the effects of carbon dioxide (CO2) and nitrogen (N) on growth of ponderosa pine seedlings produced results contradictory to those obtained in the field with the same species, soil, and treatments. In the controlled envi- ronment study, there was a significant negative growth response to N fertilization, whereas in the field there was a significant positive response to N. The difference was due to high rates of native N mineralization after soil disturbance during potting. This was evident from soil solution N03- concentrations that peaked at -5000 Kmol/L in the unfertilized pots and 20000 Kmol/L in the fertilized pots. These concentrations are orders of magnitude greater than those typically observed in the field. The effects of soil disturbance on N mineralization and nitrification need to be carefully considered before initiating controlled environment studies. The results of this study show that excessive N mineralization caused by soil disturbance can seriously compromise the results of controlled environment studies
- Published
- 1995
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30. Effects of elevated CO2 and nitrogen on nutrient uptake in ponderosa pine seedlings
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Dale W. Johnson, Timothy Ball, and Roger F. Walker
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Soil Science ,Plant Science - Published
- 1995
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31. Circumferential strut fracture as a mechanism of 'crush' bifurcation restenosis
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Renu Virmani, Timothy Ball, Sulaiman Rathore, Masataka Nakano, Aaron V. Kaplan, and Jason Foerst
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Coronary Angiography ,Coronary Restenosis ,Restenosis ,medicine ,Humans ,cardiovascular diseases ,Bifurcation ,Aged ,business.industry ,musculoskeletal, neural, and ocular physiology ,Stent ,Drug-Eluting Stents ,Microcomputed tomography ,equipment and supplies ,medicine.disease ,Coronary Vessels ,Prosthesis Failure ,surgical procedures, operative ,nervous system ,Fracture (geology) ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
The "Crush" procedure is a 2-stent technique for the treatment of bifurcation lesions with greater rates of in-stent restenosis than the Culotte technique. In conclusion, we report a possible mechanism for this discrepancy in the case of severe Crush stent fracture with associated focal restenosis identified by postmortem microcomputed tomography and histologic examination.
- Published
- 2012
32. Soil pCO2, soil respiration, and root activity in CO2-fumigated and nitrogen-fertilized ponderosa pine
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Dale Johnson, Donn Geisinger, Roger Walker, John Newman, James Vose, Katherine Elliot, and Timothy Ball
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Soil Science ,Plant Science - Published
- 1994
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33. The complementary role of microCT and histopathology in characterizing the natural history of stented arteries
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Timothy Ball, Marc Vorpahl, Jason R. Foerst, Aaron V. Kaplan, Malte Kelm, and Renu Virmani
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medicine.medical_specialty ,Vascular imaging ,business.industry ,General Medicine ,Precordial examination ,X-Ray Microtomography ,Microcomputed tomography ,Coronary Vessels ,Natural history ,Imaging, Three-Dimensional ,Cardiovascular Diseases ,Internal Medicine ,medicine ,Animals ,Humans ,Histopathology ,Stents ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
Microcomputed tomography is an important tool for preclinical vascular imaging, with micron-level resolution. This nondestructive means of imaging allows for rapid collection of 2D and 3D reconstructions to visualize pathologic specimens. Postmortem analysis of stented arteries has yielded significant insights into the ‘natural’ history of stented arteries. This article outlines a protocol for ex vivo, postmortem cardiac examination of stented arterial segments with microcomputed tomography followed by histopathologic analysis and highlights the complementary nature of these modalities.
- Published
- 2011
34. AN ICONOCLAST’S VIEW OF CLIMATIC CHANGE
- Author
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Timothy Ball
- Subjects
Environmental science ,Climate change ,Physical geography ,Water Science and Technology - Published
- 1992
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35. Physiological and environmental regulation of stomatal conductance, photosynthesis and transpiration: a model that includes a laminar boundary layer
- Author
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Joseph A. Berry, J. Timothy Ball, G. James Collatz, and Cyril Grivet
- Subjects
Canopy ,Hydrology ,Atmospheric Science ,Global and Planetary Change ,Stomatal conductance ,Chemistry ,Humidity ,Conductance ,Forestry ,Atmospheric sciences ,Canopy conductance ,Boundary layer ,Latent heat ,Agronomy and Crop Science ,Transpiration - Abstract
This paper presents a system of models for the simulation of gas and energy exchange of a leaf of a C3 plant in free air. The physiological processes are simulated by sub-models that: (a) give net photosynthesis (An) as a function of environmental and leaf parameters and stomatal conductance (gs); (b) give g, as a function of the concentration of CO2 and H2O in air at the leaf surface and the current rate of photosynthesis of the leaf. An energy balance and mass transport sub-model is used to couple the physiological processes through a variable boundary layer to the ambient environment. The models are based on theoretical and empirical analysis of gs, and An measured at the leaf level, and tests with intact attached leaves of soybeans show very good agreement between predicted and measured responses of gs and An over a wide range of leaf temperatures (20–35°C), CO2 concentrations (10–90 Pa), air to leaf water vapor deficits (0.5–3.7 kPa) and light intensities (100–2000 μmol m−2s−1). The combined models were used to simulate the responses of latent heat flux (λE) and gs for a soybean canopy for the course of an idealized summer day, using the ‘big-leaf’ approximation. Appropriate data are not yet available to provide a rigorous test of these simulations, but the response patterns are similar to field observations. These simulations show a pronounced midday depression of λE and gs at low or high values of boundary-layer conductance. Deterioration of plant water relations during midday has often been invoked to explain this common natural phenomenon, but the present models do not consider this possibility. Analysis of the model indicates that the simulated midday depression is, in part, the result of positive feedback mediated by the boundary layer. For example, a change in gs affects An and λE. As a consequence, the temperature, humidity and CO2 concentration of the air in the proximity of the stomata (e.g. the air at the leaf surface) change and these, in turn, affect gs. The simulations illustrate the possible significance of the boundary layer in mediating feedback loops which affect the regulation of stomatal conductance and λE. The simulations also examine the significance of changing the response properties of the photosynthetic component of the model by changing leaf protein content or the CO2 concentration of the atmosphere.
- Published
- 1991
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36. Environmental pollution and impacts on soils and forests nutrition in North America
- Author
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Dale W. Johnson and J. Timothy Ball
- Subjects
Environmental Engineering ,Ecology ,Ecological Modeling ,Forest management ,Environmental pollution ,Pollution ,Soil contamination ,Leaching model ,Nutrient ,Deposition (aerosol physics) ,Soil water ,Forest ecology ,Environmental Chemistry ,Environmental science ,Water Science and Technology - Abstract
The effects of acid deposition, excess N deposition, and elevated CO2 on forest soils and nutrition in North America are reviewed. While there remains the possibility that acid deposition and excess N deposition are contributing to declines in red spruce, sugar maple, and southern pines, clearcut cause and effects are still not evident. Climate is clearly a major factor in red spruce decline in the northeastern U.S., but air pollution may contribute. There is some evidence that soil solution Al may be approaching deleterious levels in southeastern red spruce forests. Lack of proper management may be a major factor in the sugar maple and southern pine declines, but once again, air pollution as a potential contributor cannot be ignored. Nutrient budget analyses and discoveries of soils base cation depletion in certain sites suggest that base cation status is declining in forests of the southeastern U.S., but thus far, base cation deficiencies are uncommon. Recent research has revealed that there are more cases of N-saturated forests in North America than was previously suspected. These systems are characterized by high rates of soil N mineralization, high atmospheric N inputs, low uptakes, or some combination of these factors. Soil leaching and Al mobilization in such systems is often dominated by nitrate. However, the geographical extent of these types of systems is limited, and the traditional view that most forest ecosystems are N limited remains valid, especially where forest management is intensive. The limited information available on tree response to CO2. suggests N-deficient plants often grow faster with elevated CO2, whereas P-deficient plants often do not. Research is needed to 1) determine if the differences in response between N- and P-deficient plants is common, 2) the responses of plants deficient in other nutrients to elevated CO2, and 3) the interactions of CO2 increase, nutrient deficiencies, climate change.
- Published
- 1990
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37. THE EFFECT OF ADDING CLOPIDOGREL OR WARFARIN TO THE GOLD STANDARD, ASPIRIN, ON THE RATE OF REPEAT CORONARY ANGIOGRAPHY AND EARLY SAPHENOUS VEIN GRAFT FAILURE
- Author
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Dexter Deleon, Timothy Ball, Fregenet Alemu, Micheal Bentley, Sulaiman Rathore, and Jason Payne
- Subjects
Coronary angiography ,medicine.medical_specialty ,Aspirin ,business.industry ,Gold standard ,Saphenous vein graft ,Warfarin ,medicine.disease ,Clopidogrel ,Surgery ,Angina ,surgical procedures, operative ,Internal medicine ,medicine ,Cardiology ,Acute thrombosis ,Cardiology and Cardiovascular Medicine ,business ,medicine.drug - Abstract
CABG is known to improve patient’s survival and alleviate symptoms of angina. Early saphenous vein graft failure (ESVGF), from acute thrombosis, is seen in 15-45 % of implanted grafts within the first year, a major cause of morbidity and mortality. Current guidelines recommend the sole use of
- Published
- 2015
- Full Text
- View/download PDF
38. EXERTIONAL DYSPNEA IN A YOUNG ATHLETE; ARTERIAL HYPOXEMIA CLUES A SINISTER PATHOLOGY
- Author
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Timothy Ball and Timothy R. Larsen
- Subjects
medicine.medical_specialty ,biology ,business.industry ,Athletes ,Arterial hypoxemia ,Exertional dyspnea ,Exercise-Induced Bronchospasm ,biology.organism_classification ,respiratory tract diseases ,Internal medicine ,Physical therapy ,medicine ,Cardiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
Exercise induced dyspnea (EID) is a common complaint in young athletes. Exercise induced bronchospasm (EIB) is recognized as the most common cause of EID in otherwise healthy athletes. Often these young patients are treated empirically without definitive diagnosis. Clinicians must recognize when
- Published
- 2015
- Full Text
- View/download PDF
39. CO2 and N-fertilization effects on fine-root length, production, and mortality: a 4-year ponderosa pine study
- Author
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Dale W. Johnson, Mark Johnson, Donald L. Phillips, David T. Tingey, J. Timothy Ball, and Marjorie J. Storm
- Subjects
Life span ,Atmosphere ,Nitrogen ,Environmental factor ,Biology ,Carbon Dioxide ,medicine.disease_cause ,Video image ,Plant Roots ,Life stage ,Pinus ponderosa ,Human fertilization ,Animal science ,Root length ,Standing crop ,Seedlings ,Botany ,medicine ,Juvenile ,Fertilizers ,Ecology, Evolution, Behavior and Systematics - Abstract
We conducted a 4-year study of juvenile Pinus ponderosa fine root (or =2 mm) responses to atmospheric CO2 and N-fertilization. Seedlings were grown in open-top chambers at three CO2 levels (ambient, ambient+175 mumol/mol, ambient+350 mumol/mol) and three N-fertilization levels (0, 10, 20 g m(-2) year(-1)). Length and width of individual roots were measured from minirhizotron video images bimonthly over 4 years starting when the seedlings were 1.5 years old. Neither CO2 nor N-fertilization treatments affected the seasonal patterns of root production or mortality. Yearly values of fine-root length standing crop (m m(-2)), production (m m(-2) year(-1)), and mortality (m m(-2) year(-1)) were consistently higher in elevated CO2 treatments throughout the study, except for mortality in the first year; however, the only statistically significant CO2 effects were in the fine-root length standing crop (m m(-2)) in the second and third years, and production and mortality (m m(-2) year(-1)) in the third year. Higher mortality (m m(-2) year(-1)) in elevated CO2 was due to greater standing crop rather than shorter life span, as fine roots lived longer in elevated CO2. No significant N effects were noted for annual cumulative production, cumulative mortality, or mean standing crop. N availability did not significantly affect responses of fine-root standing crop, production, or mortality to elevated CO2. Multi-year studies at all life stages of trees are important to characterize belowground responses to factors such as atmospheric CO2 and N-fertilization. This study showed the potential for juvenile ponderosa pine to increase fine-root C pools and C fluxes through root mortality in response to elevated CO2.
- Published
- 2005
40. Photosynthetic adjustment in field-grown ponderosa pine trees after six years of exposure to elevated CO(2)
- Author
-
J. Timothy Ball, David T. Tissue, and Kevin L. Griffin
- Subjects
biology ,Physiology ,RuBisCO ,Growing season ,chemistry.chemical_element ,Plant Science ,Photosynthesis ,Nitrogen ,Photosynthetic capacity ,chemistry.chemical_compound ,Horticulture ,chemistry ,Carboxylation ,Chlorophyll ,Carbon dioxide ,Botany ,biology.protein - Abstract
Photosynthesis of tree seedlings is generally enhanced during short-term exposure to elevated atmospheric CO(2), but longer-term photosynthetic responses are often more variable because they are affected by morphological, biochemical and physiological feedback mechanisms that regulate carbon assimilation to meet sink demand. To examine biochemical and morphological factors that might regulate the long-term photosynthetic response of field-grown trees to elevated CO(2), we grew ponderosa pine (Pinus ponderosa Dougl. ex Laws.) trees in open-top chambers for six years in native soil at ambient CO(2) (35 Pa) and elevated CO(2) (70 Pa) at a site near Placerville, CA. Trees were well watered and exposed to natural light and ambient temperature. At the end of the sixth growing season at elevated CO(2), net photosynthesis was enhanced 53%, despite reductions in photosynthetic capacity. The positive net photosynthetic response to elevated CO(2) reflected greater relative increases in Rubisco sensitivity compared with the decreases resulting from biochemical adjustments. Analyses of net photosynthetic rate versus internal CO(2) partial pressure curves indicated that reductions in photosynthetic capacity in response to elevated CO(2) were the result of significant reductions in maximum photosynthetic rate (20%), Rubisco carboxylation capacity (36%), and electron transport capacity (21%). Decreased photosynthetic capacity was accompanied by reductions in various photosynthetic components, including total chlorophyll (24%), Rubisco protein content (38%), and mass-based leaf nitrogen concentration (14%). Net photosynthesis was unaffected by morphological adjustments because there was no change in leaf mass per unit area at elevated CO(2). An apparent positive response of photosynthetic adjustment in the elevated CO(2) treatment was the redistribution of N within the photosynthetic system to balance Rubisco carboxylation and electron transport capacities. We conclude that trees, without apparent limitations to root growth, may exhibit photosynthetic adjustment responses in the field after long-term exposure to elevated CO(2).
- Published
- 2003
41. Book Review: 'Climate Cover-up: The Crusade to Deny Global Warming'
- Author
-
Timothy Ball
- Subjects
Environmental Engineering ,Renewable Energy, Sustainability and the Environment ,Energy Engineering and Power Technology ,Energy (miscellaneous) - Published
- 2010
- Full Text
- View/download PDF
42. Book Review: 'Distributional Impacts of Climate Change and Disasters'
- Author
-
Timothy Ball
- Subjects
Geography ,Environmental Engineering ,business.industry ,Renewable Energy, Sustainability and the Environment ,Natural resource economics ,Political economy of climate change ,Climatology ,Environmental resource management ,Economics ,Energy Engineering and Power Technology ,Climate change ,business ,Energy (miscellaneous) - Published
- 2010
- Full Text
- View/download PDF
43. Photosynthetic adjustment in field-grown ponderosa pine trees after six years exposure to elevated CO{sub 2}
- Author
-
Kevin L. Griffin, J. Timothy Ball, and David T. Tissue
- Subjects
chemistry.chemical_compound ,Agronomy ,Field (physics) ,Carboxylation ,Chemistry ,Botany ,Carbon dioxide ,chemistry.chemical_element ,Photosynthesis ,Nitrogen - Published
- 1998
- Full Text
- View/download PDF
44. The photosynthesis - leaf nitrogen relationship at ambient and elevated atmospheric carbon dioxide: a meta-analysis
- Author
-
Peter S. Curtis, Andrew G. Peterson, M. Forstreuter, David T. Tissue, Christopher B. Field, Yiqi Luo, Richard J. Norby, Peter B. Reich, J. Timothy Ball, Ana Rey, Christoph S. Vogel, Carla S Gunderson, and Kevin L. Griffin
- Subjects
Carbon dioxide in Earth's atmosphere ,chemistry.chemical_element ,Biology ,Atmospheric sciences ,Photosynthesis ,Nitrogen ,chemistry.chemical_compound ,Deciduous ,chemistry ,Vegetation type ,Content (measure theory) ,Botany ,Carbon dioxide ,Ecosystem - Abstract
Estimation of leaf photosynthetic rate (A) from leaf nitrogen content (N) is both conceptually and numerically important in models of plant, ecosystem and biosphere responses to global change. The relationship between A and N has been studied extensively at ambient CO{sub 2} but much less at elevated CO{sub 2}. This study was designed to (1) assess whether the A-N relationship was more similar for species within than between community and vegetation types, and (2) examine how growth at elevated CO{sub 2} affects the A-N relationship. Data were obtained for 39 C{sub 3} species grown at ambient CO{sub 2} and 10 C{sub 3} species grown at ambient and elevated CO{sub 2}. A regression model was applied to each species as well as to species pooled within different community and vegetation types. Cluster analysis of the regression coefficients indicated that species measured at ambient CO{sub 2} did not separate into distinct groups matching community or vegetation type. Instead, most community and vegetation types shared the same general parameter space for regression coefficients. Growth at elevated CO{sub 2} increased photosynthetic nitrogen use efficiency for pines and deciduous trees. When species were pooled by vegetation type, the A-N relationship for deciduous trees expressed on a leaf-mass bask was not altered by elevated CO{sub 2}, while the intercept increased for pines. When regression coefficients were averaged to give mean responses for different vegetation types, elevated CO{sub 2} increased the intercept and the slope for deciduous trees but increased only the intercept for pines. There were no statistical differences between the pines and deciduous trees for the effect of CO{sub 2}. Generalizations about the effect of elevated CO{sub 2} on the A-N relationship, and differences between pines and deciduous trees will be enhanced as more data become available.
- Published
- 1998
- Full Text
- View/download PDF
45. Climate change and wetland processes in the Southwest United States: Response of riparian communities to rising CO{sub 2} levels. Final report
- Author
-
John B. Picone, Andrew G. Peterson, Anne M. Hoylman, J. Timothy Ball, and John V.H. Constable
- Subjects
geography ,geography.geographical_feature_category ,Ecology ,Environmental science ,Resource use ,Climate change ,Wetland ,Competitive interaction ,Riparian zone - Abstract
The current impact of Salt Cedar on the riparian areas of the southwestern US are recognized as being negative. If atmospheric levels of CO{sub 2} continue to rise--as seems likely--the results of this study indicate that the Salt Cedar--Cottonwood competitive interaction maybe moved further in the direction of favoring Salt Cedar. Further study confirming these results and elucidating the basis for competitive resource use by Salt Cedar and other riparian species would be prudent.
- Published
- 1998
- Full Text
- View/download PDF
46. Michael Davis, trombone
- Author
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Davis, Michael R., 1961 August 13-; Ball State University. Jazz Ensemble; Morrissey, Ben; Van Cleave, Timothy; Ball State University. Studio Jazz Ensemble; Frazier, Will; Ball State University. Jazz Lab Ensemble; McWilliams, Larry N., Ball State University. School of Music, Davis, Michael R., 1961 August 13-; Ball State University. Jazz Ensemble; Morrissey, Ben; Van Cleave, Timothy; Ball State University. Studio Jazz Ensemble; Frazier, Will; Ball State University. Jazz Lab Ensemble; McWilliams, Larry N., and Ball State University. School of Music
- Abstract
With the Jazz Ensemble, the Studio Jazz Ensemble, and the Jazz Lab Ensemble.; Includes lengthy program notes about The Art of Jazz Series.; Includes biographical notes about (with black-and-white portrait photographs of) trumpeter & educator Larry N. McWilliams and trombonist & composer Michael Davis.; Includes lists of the personnel of the Jazz Ensemble, the Studio Jazz Ensemble, and the Jazz Lab Ensemble., Series LXI, Number 205., This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about
- Published
- 2007
47. Spring concert
- Author
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Ball State University. Women's Chorus; Wahl, Shelbie L.; McCoskey, Kate; Ball State University. Statesmen; Lister, Michael C.; Boaz, Timothy; Ball State University. Choral Union; Thorngate, Russell, Ball State University. School of Music, Ball State University. Women's Chorus; Wahl, Shelbie L.; McCoskey, Kate; Ball State University. Statesmen; Lister, Michael C.; Boaz, Timothy; Ball State University. Choral Union; Thorngate, Russell, and Ball State University. School of Music
- Abstract
With the Women's Chorus, the Statesmen, and the Choral Union.; Includes program notes about each piece, with lyrics for some pieces.; Includes lists of the personnel of the Statesmen, the Women's Chorus, and the Choral Union., Series LXI, Number 227., This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about
- Published
- 2007
48. Winter choral concert
- Author
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Ball State University. Statesmen; Lister, Michael C.; Boaz, Timothy; Ball State University. Women's Chorus; Wahl, Shelbie L.; McCoskey, Kate; Ball State University. Choral Union; Thorngate, Russell, Ball State University. School of Music, Ball State University. Statesmen; Lister, Michael C.; Boaz, Timothy; Ball State University. Women's Chorus; Wahl, Shelbie L.; McCoskey, Kate; Ball State University. Choral Union; Thorngate, Russell, and Ball State University. School of Music
- Abstract
With the Statesmen, the Women's Chorus, and the Choral Union.; Includes program notes about each piece, with some biographical information about the composers.; Includes lists of the personnel of the Statesmen, the Women's Chorus, and the Choral Union., Series LXI, Number 154., This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about
- Published
- 2007
49. Latin Percussion Ensemble [and] Marimba-Percussion Ensemble II
- Author
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Ball State University. Latin Percussion Ensemble; Van Cleave, Timothy; Ball State University. Marimba-Percussion Ensemble; Sterk, Jeremy; Newbill, William; Brown, Michael, Ball State University. School of Music, Ball State University. Latin Percussion Ensemble; Van Cleave, Timothy; Ball State University. Marimba-Percussion Ensemble; Sterk, Jeremy; Newbill, William; Brown, Michael, and Ball State University. School of Music
- Abstract
Timothy Van Cleave, director of the Latin Percussion Ensemble.; Jeremy Sterk, director of the Marimba-Percussion Ensemble II.; Includes lists of the personnel of the Latin Percussion Ensemble & the Marimba-Percussion Ensemble II., Series LXII, Number 77., This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about
- Published
- 2007
50. Choral ensembles concert
- Author
-
Ball State University. Statesmen; Lister, Michael C.; Boaz, Timothy; Ball State University. Women's Chorus; Wahl, Shelbie L.; McCoskey, Kate; Ball State University. Choral Union; Thorngate, Russell, Ball State University. School of Music, Ball State University. Statesmen; Lister, Michael C.; Boaz, Timothy; Ball State University. Women's Chorus; Wahl, Shelbie L.; McCoskey, Kate; Ball State University. Choral Union; Thorngate, Russell, and Ball State University. School of Music
- Abstract
With the Statesmen, the Women's Chorus, and the Choral Union.; Includes program notes about each piece, with lyrics for some pieces.; Includes lists of the personnel of the Statesmen, the Women's Chorus, and the Choral Union., Series LXI, Number 35., This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about
- Published
- 2006
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