656 research outputs found
Uncovering statistical features of bradycardia severity in premature infants using a point process model
No full textPredicting Bradycardia in Preterm Infants Using Point Process Analysis of Heart Rate
No full textObjective: Episodes of bradycardia are common and recur sporadically in preterm infants, posing a threat to the developing brain and other vital organs. We hypothesize that bradycardias are a result of transient temporal destabilization of the cardiac autonomic control system and that fluctuations in the heart rate signal might contain information that precedes bradycardia. We investigate infant heart rate fluctuations with a novel application of point process theory. Methods: In ten preterm infants, we estimate instantaneous linear measures of the heart rate signal, use these measures to extract statistical features of bradycardia, and propose a simplistic framework for prediction of bradycardia. Results: We present the performance of a prediction algorithm using instantaneous linear measures (mean area under the curve = 0.79 ± 0.018) for over 440 bradycardia events. The algorithm achieves an average forecast time of 116 s prior to bradycardia onset (FPR = 0.15). Our analysis reveals that increased variance in the heart rate signal is a precursor of severe bradycardia. This increase in variance is associated with an increase in power from low content dynamics in the LF band (0.04-0.2 Hz) and lower multiscale entropy values prior to bradycardia. Conclusion: Point process analysis of the heartbeat time series reveals instantaneous measures that can be used to predict infant bradycardia prior to onset. Significance: Our findings are relevant to risk stratification, predictive monitoring, and implementation of preventative strategies for reducing morbidity and mortality associated with bradycardia in neonatal intensive care units
Marginal longitudinal nonparametric regression: locality and efficiency of spline and kernel methods
No full textWe consider nonparametric regression in a longitudinal marginal model of generalized estimating equation (GEE) type with a time-varying covariate in the situation where the number of observations per subject is finite and the number of subjects is large. In such models, the basic shape of the regression function is affected only by the covariate values and not otherwise by the ordering of the observations. Two methods of estimating the nonparametric function can be considered: kernel methods and spline methods. Recently, surprising evidence has emerged suggesting that for kernel methods previously proposed in the literature, it is generally asymptotically preferable to ignore the correlation structure in our marginal model and instead assume that the data are independent, that is, working independence in the GEE jargon. As seen through equivalent kernel results, in univariate independent data problems splines and kernels have similar behavior; smoothing splines are equivalent to kernel regression with a specific higher-order kernel, and hence smoothing splines are local. This equivalence suggests that in our marginal model, working independence might be preferable for spline methods. Our results suggest the opposite; via theoretical and numerical calculations, we provide evidence suggesting that for our marginal model, marginal smoothing and penalized regression splines are not local in their behavior. In contrast to the kernel results, our evidence suggests that when using spline methods, it is worthwhile to account for the correlation structure. Our results also suggest that spline methods appear to be more efficient than the previously proposed kernel methods for our marginal model
Improving heart rate estimation in preterm infants with bivariate point process analysis of heart rate and respiration
No full textAccurate estimation of heart rate dynamics in preterm infants is important for predicting recurrent episodes of severe bradycardia. We hypothesize that estimation of heart rate can be improved by including respiration as a state variable, based on mechanisms that underlie cardio-respiratory coherence. For ten preterm infants, we demonstrate that including respiration as a covariate improves estimation accuracy by an average of 11% across bradycardia severity, and reduces the maximum error by 8%. We also find that cardio-respiratory coherence increases in low frequency content just prior to severe bradycardia. Thus, incorporating respiratory information may improve models of heart rate dynamics and narrow potential features for bradycardia prediction
E. Gordon Gee - President, The Ohio State University
No full textE. Gordon Gee is president of The Ohio State University, a world-class public research institution and one of the nation’s most distinguished land-grant universities. As chief executive officer, he oversees Ohio State’s six campuses, 65,000 students, and 48,000 faculty and staff. Gee is among the most highly experienced and respected leaders in higher education, having been named in 2009 by Time magazine as one of the top 10 university presidents in the United States. Prior to his service at Ohio State, he led Vanderbilt University (2001–2007), Brown University (1998–2000), The Ohio State University (1990–97), the University of Colorado (1985–90), and West Virginia University (1981–85).
Born in Vernal, Utah, Gee graduated from the University of Utah with an honors degree in history and earned his J.D. and Ed.D. degrees from Columbia University. He clerked under Chief Justice David T. Lewis of the U.S. 10th Circuit Court of Appeals before being named a judicial fellow and staff assistant to the U.S. Supreme Court. In this role, he worked for Chief Justice Warren Burger on administrative and legal problems of the court and federal judiciary. Gee returned to Utah as an associate professor and associate dean in the J. Reuben Clark Law School at Brigham Young University, and was granted full professorship in 1978. One year later, he was named dean of the West Virginia University Law School, and, in 1981, was appointed to that university’s presidency.
Gee is a member of several education-governance organizations and committees, including the Big Ten Conference Council of Presidents, the Inter-University Council of Ohio, the Business-Higher Education Forum, and the American Association of Universities. He is chair of the American Council on Education’s Commission on Higher Education Attainment and serves as co-chair of the Association of Public and Land-Grant Universities’ Energy Advisory Committee. In 2009, Gee was invited to join the International Advisory Board of King Adbulaziz University in Saudi Arabia. Active in a number of national professional and service organizations, he also serves on the boards for the Rock and Roll Hall of Fame and Museum, Inc., Limited Brands, and the National 4-H Council. In 2011, Gee was appointed to serve as secretary on the Board of Directors of Ohio’s economic development program, JobsOhio.
Gee has received a number of honorary degrees, awards, fellowships, and recognitions. He is a fellow of the prestigious American Association for the Advancement of Science, the world’s largest science organization. In 1994, Gee received the Distinguished Alumnus Award from the University of Utah, as well as from Teachers College of Columbia University. He is the co-author of 11 books, including the recentLaw, Policy and Higher Education, which is currently in press. He is also the author of numerous papers and articles on law and education.
Gee’s daughter, Rebekah, is the director of the Louisiana Birth Outcomes Project, and an assistant professor of Public Health and Medicine at Louisiana State University. She is also a Norman F. Gant/American Board of Obstetrics and Gynecology/IOM Anniversary Fellow.https://corescholar.libraries.wright.edu/archives_presidential_lecture_series/1017/thumbnail.jp
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The decline and fall of the human empire ::why our species is on the edge of extinction /
No full text"By the award-winning author of A (Very) Short History of Life on Earth: a history of humanity on the brink of decline. We are living through a period that is unique in human history. For the first time in more than ten thousand years, the rate of human population growth is slowing down. In the middle of this century population growth will stop, and the number of people on Earth will start to decline - fast. In this provocative book, award-winning science writer Henry Gee offers a concise, brilliantly-told history of our species--and argues that we are on a rapid, one-way trip to extinction. The Decline and Fall of the Human Empire narrates the dramatic rise of humanity, how a scattered range of small groups across several continents eventually inbred, interacted, fought, established stable communities and food supplies, and began the process of dominating the planet. The human story is relatively brief-the oldest fossils of H. Sapiens date to approximately 300,000 years ago-yet the spread of our species has been unstoppable...until recently. As Gee demonstrates, our population has peaked, and is declining; our environment is becoming inimical to human life in many locations; our core resources of water, arable land, and air are diminishing; and new diseases, simmering conflicts, and ambiguous technologies threaten our collective health. Can we still change our course? Or is our own extinction inevitable? There could be a way out, but the launch window is narrow. Unless Homo sapiens establishes successful colonies in space within the next two centuries, our species is likely to stay earthbound and will have vanished entirely within another ten thousand years, bringing the seven-million-year story of the human lineage to an end. With assured narration, dramatic stories, and his signature sprightly humor, Henry Gee envisions new opportunities for the future of humanity-a future that will reward facing challenges with ingenuity, foresight, and cooperation"-
Has agricultural policy responded to the Rio challenge?
No full textThis paper examines recent changes in EU agricultural policy and its implementation in Ireland and asks whether the changes made encourage a more sustainable agriculture in Ireland in line with the objectives of the Rio UN Conference on the Environment and Development. It argues that the Agenda 2000 reforms of the CAP common market regimes will have only a modest environmental impact. The extension of horizontal environmental cross-compliance in determining eligibility to receive direct payments will have a potentially larger impact, but carries the danger that it may legitimise current compensatory payments as payments for environmental services provided by farmers, even though the standard of farming required is only good farming practice. The implementation of the EU's agri-environment scheme in Ireland is also evaluated, and it is argued that the focus of the scheme should be shifted more from avoiding pollution to habitat protection and creation.
Investigating the effects of typical rowing strength training practices on strength and power development and 2,000m rowing performance
No full textThis study aimed to determine the effects of a short-term, strength training intervention, typically undertaken
by club-standard rowers, on 2,000 m rowing performance and strength and power development. Twenty-eight male
rowers were randomly assigned to intervention or control groups. All participants performed baseline testing involving assessments of muscle soreness, creatine kinase activity (CK), maximal voluntary contraction (leg-extensors) (MVC),static-squat jumps (SSJ), counter-movement jumps (CMJ), maximal rowing power strokes (PS) and a 2,000 m rowing ergometer time-trial (2,000 m) with accompanying respiratory-exchange and electromyography (EMG) analysis.
Intervention group participants subsequently performed three identical strength training (ST) sessions, in the space of five days, repeating all assessments 24 h following the final ST. The control group completed the same testing procedure but with no ST. Following ST, the intervention group experienced significant elevations in soreness and CK activity, and decrements in MVC, SSJ, CMJ and PS (p < 0.01). However, 2,000 m rowing performance, pacing strategy and gas exchange were unchanged across trials in either condition. Following ST, significant increases occurred for EMG (p < 0.05), and there were non-significant trends for decreased blood lactate and anaerobic energy liberation (p = 0.063 – 0.086). In summary, club-standard rowers, following an intensive period of strength training, maintained their 2,000 m rowing performance despite suffering symptoms of muscle damage and disruption to muscle function. This disruption likely reflected the presence of acute residual fatigue, potentially in type II muscle fibres as strength and power development were affected
Academic Perspectives on Agribusiness: An International Survey
No full textThe IFAMR is published by (IFAMA) the International Food and Agribusiness Management Review. www.ifama.orgpromotion and tenure, agribusiness, teaching, grantsmanship, research, Agribusiness, Institutional and Behavioral Economics, Productivity Analysis, Teaching/Communication/Extension/Profession, Q130,
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