Full text
Available for:
CMK, CTK, FMFMET, IJS, NUK, PNG, UM
62.
Using physiological signals to predict apnea in preterm infants Williamson, J. R.; Bliss, D. W.; Browne, D. W. ...
2011 Conference Record of the Forty Fifth Asilomar Conference on Signals, Systems and Computers (ASILOMAR),
2011-Nov.
Conference Proceeding
Apnea of prematurity, a common developmental disorder in preterm infants, is implicated in long-term neurodevelopmental deficits. Preventative clinical interventions, such as mechanosensory ...stimulation, would benefit from predictive knowledge of when the patient is at high risk for apnea. In this study, the predictive utility of features derived from breathing rate and heart rate is explored. Specifically, the multiscale correlation structure of interbreath intervals and heartbeat intervals is used to train a patient-specific apnea prediction algorithm. The algorithm's prediction results are significantly better than chance for three of the six patients it is evaluated on. These preliminary studies suggest that features of cardiopulmonary signals can anticipate the occurrence of clinically significant apneas in preterm infants.
To examine the effect of intravenous iodinated contrast material administration on the subsequent development of acute kidney injury (AKI), emergent dialysis, and short-term mortality using a ...propensity score-adjusted analysis of computed tomographic scan recipients with chronic kidney disease (CKD).
In this institutional review board-approved retrospective study, all patients with CKD who received a contrast-enhanced (contrast group) or unenhanced (noncontrast group) computed tomographic scan from January 1, 2000, to August 1, 2013 were identified. Patients were subdivided into CKD stage III (baseline estimated glomerular filtration rate, 30-59 mL/min per 1.73 m(2)) and CKD stage IV-V (baseline estimated glomerular filtration rate, <30 mL/min per 1.73 m(2)) subgroups and separately underwent propensity score generation, stratification, and 1:1 matching. Rates of AKI, 30-day emergent dialysis, and mortality were compared between contrast and noncontrast groups. Sensitivity analyses examining only patients with stable prescan serum creatinine levels and incorporating intravenous fluid administration at the time of the CT scan into the model were also performed.
A total of 6902 patients (4496 CKD stage III, matched: 1220 contrast and 1220 noncontrast; 2086 CKD stage IV-V, matched: 491 contrast and 491 noncontrast) were included in the study. After propensity score adjustment, rates of AKI, emergent dialysis, and mortality were not significantly higher in the contrast group than in the noncontrast group in either CKD subgroup (CKD stage III: OR, 0.65-1.00; P<.001-.99 and CKD stage IV-V: OR, 0.93-2.33; P=.22-.99). Both sensitivity analyses revealed similar results.
Intravenous contrast material administration was not associated with an increased risk of AKI, emergent dialysis, and short-term mortality in a cohort of patients with diminished renal function.
We have measured the differential cross section for the gamman-->pi(-)p and gammap-->pi(+)n reactions at theta(c.m.)=90 degrees in the photon energy range from 1.1 to 5.5 GeV at Jefferson Lab (JLab). ...The data at E(gamma) greater, similar 3.3 GeV exhibit a global scaling behavior for both pi(-) and pi(+) photoproduction, consistent with the constituent counting rule and the existing pi(+) photoproduction data. Possible oscillations around the scaling value are suggested by these new data. The data show enhancement in the scaled cross section at a center-of-mass energy near 2.2 GeV. The cross section ratio of exclusive pi(-) to pi(+) photoproduction at high energy is consistent with the prediction based on one-hard-gluon-exchange diagrams.
Full text
Available for:
CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The role of nitric oxide in the immune response to allogeneic tissue was explored in an in vivo cardiac transplant model in the rat. Nitric oxide production during organ rejection was demonstrated by ...elevations in systemic serum nitrite/nitrate levels and by electron paramagnetic resonance spectroscopy. Messenger RNA for the inducible nitric oxide synthase enzyme was detected in the rejecting allografted heart, but not in the nonrejecting isografted heart. The enzyme was demonstrated to be biologically active by the in vitro conversion of L-arginine to L-citrulline and was immunohistochemically localized to the infiltrating inflammatory cells. Treatment with aminoguanidine, a preferential inhibitor of the inducible nitric oxide synthase isoform, prevented the increased nitric oxide production in the transplanted organ and significantly attenuated the pathogenesis of acute rejection. Aminoguanidine treatment prolonged graft survival, improved graft contractile function, and significantly reduced the histologic grade of rejection. These results suggest an important role for nitric oxide in mediating the immune response to allogeneic tissue. Inhibition of inducible nitric oxide synthase may provide a novel therapeutic modality in the management of acute transplant rejection and of other immune-mediated processes.
In this article, I propose a theory of pedagogical praxis. Pedagogical praxis begins with the premise that under the right conditions, computers and other information technologies can make it easier ...for students to become active participants in meaningful projects and practices in the life of their community and suggests that professional practices such as architecture, mediation, and journalism can provide constructive models for helping students learn from such experiences. In this vision, new technology reinvigorates Dewey's (1915) idea of linking school with society. Technology builds a bridge that allows young people to participate in the learning practices of professionals; in the process, they develop epistemological frameworks that organize the skills, habits, and understandings they need to thrive in a complex, postindustrial society. Although further work needs to be done to explore the processes through which such learning can take place, studies suggest that this perspective may be a productive avenue for continuing research. This article presents an overview of the theories and methods that inform such work.
Purpose: Intracranial electrode recording often provides localization of the site of seizure onset to allow epilepsy surgery. In patients whose invasive evaluation fails to localize seizure origin, ...the utility of further invasive monitoring is unknown. This study was undertaken to explore the hypothesis that a second intracranial investigation is selected patients warrants consideration and can lead to successful epilepsy surgery.
Methods: A series of 110 consecutive patients with partial epilepsy who had undergone intracranial electrode evaluation (by subdural strip, subdural grid, and/or depth electrodes) between February 1992 and October 1998 was retrospectively analyzed. Of these, failed localization of seizure origin was thought to be due to sampling error in 13 patients. Nine of these 13 patients underwent a second intracranial investigation.
Results: Reevaluation with intracranial electrodes resulted in satisfactory seizure‐onset localization in seven of nine patients, and these seven had epilepsy surgery. Three frontal, two temporal, and one occipital resection as well as one multiple subpial transection were performed. Six patients have become seizure free, and one was not significantly improved. The mean follow‐up is 2.8 years. There was no permanent morbidity.
Conclusions: In selected patients in whom invasive monitoring fails to identify the site of seizure origin, reinvestigation with intracranial electrodes can achieve localization of the region of seizure onset and allow successful surgical treatment.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
PDF
