31 research outputs found
Critical points in a relativistic bosonic gas induced by the quantum structure of spacetime
It is well known that phase transitions arise if the interaction among
particles embodies an attractive as well as a repulsive contribution. In this
work it will be shown that the breakdown of Lorentz symmetry, characterized
through a deformation in the relation dispersion, plus the bosonic statistics
predict the emergence of critical points. In other words, in some quantum
gravity models the structure of spacetime implies the emergence of critical
points even when no interaction among the particle has been considered.Comment: 5 pages, no figure
Right Ventricular Compression Observed in Echocardiography from Pectus Excavatum Deformity
Pectus excavatum exists as varying anatomic deformities and compression of the right heart by the chest wall can lead to patient symptoms including dyspnea and chest pain with exertion. Echocardiography can be difficult but is critical to the evaluation and diagnosis of this patient population. Modifying standard views such as biplane transthoracic and 3-D transesophageal views may be necessary in some patients due to limitations from the abnormal anatomy of the deformed anterior chest wall. Apical four-chamber views when seen clearly can usually visualize any extrinsic compression to the right ventricle of the heart
Lung Function after the Minimal Invasive Pectus Excavatum Repair (Nuss Procedure)
Background The Nuss procedure was introduced at our center in 1999. The operation was mainly performed for cosmesis. Little information is available regarding the influence of this operation on lung function. Methods The aim of this study, a prospective analysis, was to analyze the effect of the Nuss procedure on lung function variables. Between 1999 and 2007 a total of 203 patients with pectus excavatum were treated with the Nuss procedure, of whom 145 (104 male, 41 female) were located at Emma Children’s Hospital. In the latter subset of consecutive patients, static lung function variables [total lung capacity (TLC), functional residual capacity (FRC), vital capacity (VC)] and dynamic lung function variables [forced expired volume in 1 s (FEV1), maximum expiratory flow (MEF50)] were performed using spirometry and body box measurements at four time points: prior to operation Some of these data were presented at the International Surgical Week
Communications Biophysics
Contains reports on nine research projects split into four sections.National Institutes of Health (Grant 5 P01 NS13126)National Institutes of Health (Grant 5 K04 NS00113)National Institutes of Health (Training Grant 5 T32 NS07047)National Institutes of Health (Grant 5 ROl NS11153-03)National Institutes of Health (Fellowship 1 T32 NS07099-01)National Science Foundation (Grant BNS77-16861)National Institutes of Health (Grant 5 ROl NS10916)National Institutes of Health (Grant 5 ROl NS12846)National Science Foundation (Grant BNS77-21751)National Institutes of Health (Grant 1 RO1 NS14092)Health Sciences FundNational Institutes of Health (Grant 2 R01 NS11680)National Institutes of Health (Grant 2 RO1 NS11080)National Institutes of Health (Training Grant 5 T32 GM07301
Early operation in children with pancreas transection
Background/Purpose: The preferred treatment for children with major pancreatic ductal injury remains controversial. This report compares our results using early operation with previously reported series using both operative and nonoperative management. Methods: This is a retrospective analysis of all children with pancreatic transection identified at Children\u27s Medical Center of Dallas, Texas, from 1995 through 1999. Results: There were 11 children with pancreatic transection. There was a delay of 2.3 days before presentation to a hospital in 6. Transection was diagnosed within 12 hours of presentation in 5 children. In the other 6 there was a mean delay of 36 hours. Nine children underwent operation within 72 hours of injury. Two late presenters initially were treated nonoperatively, and both developed a pseudocyst. The length of hospital stay in patients undergoing early operation averaged 11 days. Early postoperative morbidity occurredin 4 children and late morbidity in 1. Conclusions: Major pancreatic injuries are uncommon in children, and the diagnosis often is delayed. A high index of suspicion and repeated computed tomography scans should lead to earlier diagnosis. When compared with nonoperative management, early pancreatic resection more expeditiously returns the child to good health and lessens the inconvenience and emotional stress associated with prolonged hospitalization. Copyright © 2001 by W.B. Saunders Company
Antegrade continent enema management of chronic fecal incontinence in children
Background/Purpose: Fecal incontinence impedes social and psychological development in children. Conventional bowel management with rectal enemas, medication, and biofeedback frequently will provide intervals free of fecal soiling sufficient for children to be socially continent. Methods: This report details the improvement achieved by antegrade irrigation of the colon when conventional bowel management programs have failed to provide satisfactory intervals free of fecal soiling. Twenty-three children had conduits performed to administer antegrade continent enemas in the colon from December 1993 to May 1997. Results: Twenty of the children were available for evaluation. One child was lost to follow-up, and two were noncompliant with the irrigation program. Fourteen of the 20 children are out of diapers. Four of the six wearing diapers, do so for urinary, not fecal incontinence. Two patients (10%) still require diapers for fecal incontinence. Parents were pleased with the efficacy of antegrade irrigation and the decrease in family stress with the elimination of fecal soiling. Conclusions: Ninety percent of the children available for follow-up benefited from antegrade irrigations of the colon. The antegrade irrigations were an improvement over conventional bowel management programs because a predictable interval free of soiling could be established. This allowed families to plan activities and improved the self-esteem of their children