797 research outputs found
Hadron yields from thermalized minijets at RHIC and LHC
We calculate the yields of pions, kaons, and -mesons for RHIC and LHC
energies assuming thermodynamical equilibration of the produced minijets, and
using as input results from pQCD for the energy densities at midrapidity. In
the calculation of the production of partons and of transverse energy one has
to account for nuclear shadowing. By using two parametrizations for the gluon
shadowing one derives energy densities differing strongly in magnitude. In this
publication we link those perturbatively calculated energy densities of partons
via entropy conservation in an ideal fluid to the hadron multiplicities at
chemical freeze-out.Comment: Talk given at the International Europhysics Conference on High Energy
Physics, EPS-HEP99, Tampere, Finland, July 1999, 3 page
Hadron yields in Au+Au/Pb+Pb at RHIC and LHC from thermalized minijets
We calculate the yields of a variety of hadrons for RHIC and LHC energies
assuming thermodynamical equilibration of the produced minijets, and using as
input results from pQCD for the energy densities at midrapidity. In the
calculation of the production of partons and of transverse energy one has to
account for nuclear shadowing. By using two parametrizations for the gluon
shadowing one derives energy densities differing strongly in magnitude. In this
publication we link those perturbatively calculated energy densities of partons
via entropy conservation in an ideal fluid to the hadron multiplicities at
chemical freeze-out.Comment: 11 pages, 2 .eps figure
Single spin asymmetry for the Drell-Yan process
We calculated the single spin asymmetries for the reaction
in the framework of twist-3 QCD for
HERA energies. The necessary imaginary phase is produced by the on-shell
contribution of the quark propagator, while the long distance part is analogous
to that providing the direct photon asymmetry calculated by J. Qiu and G.
Sterman. The asymmetry turns out to be generally of the order percent.Comment: 7 pages, 4 figures, LaTe
A microscopic calculation of secondary Drell-Yan production in heavy ion collisions
A study of secondary Drell-Yan production in nuclear collisions is presented for SPS energies. In addition to the lepton pairs produced in the initial collisions of the projectile and target nucleons, we consider the potentially high dilepton yield from hard valence antiquarks in produced mesons and antibaryons. We calculate the secondary Drell-Yan contributions taking the collision spectrum of hadrons from the microscopic model URQMD. The con- tributions from meson-baryon interactions, small in hadron-nucleus interac- tions, are found to be substantial in nucleus-nucleus collisions at low dilepton masses. Preresonance collisions of partons may further increase the yields
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Body Dissatisfaction, Disordered Eating Behaviors and Body Image Quality of Life in African American Women with Hiv
The purpose of the current study was to further our understanding of the subjective experience of middle-age African American women who are HIV+ and on highly active antiretroviral therapy, particularly how self-reported lipodystrophy (LD), levels of body dissatisfaction, body image quality of life, and engagement in disordered eating behaviors are related. Multiple regression, MANOVA, MANCOVA, ANOVA, and chi-square were utilized to test hypotheses. Results revealed that HIV+ and HIV- women did not differ significantly on their levels of body dissatisfaction or drive for thinness. When HIV+ women were examined in more detail a pattern emerged: women who self-reported fat hypertrophy had significantly higher levels of body dissatisfaction, bingeing, but not purging, and dietary restriction and fear of weight gain compared to women who did not self-report LD. About 75% of the sample was overweight or obese, and when BMI was controlled for, these differences persisted for body dissatisfaction and disordered eating behaviors for fat hypertrophy, but not fat atrophy. Overall, the findings indicate that the type of LD, specifically hypertrophy, is more related to body dissatisfaction and disordered eating behaviors, than LD in general. Clinical implications and limitations of these findings are discussed
Sustainable Roof Systems: Design Report
This report describes the design of a prefabricated sustainable roof system for LionForce Systems. While being economical, environmentally sustainable, aesthetically pleasing, and easy to assemble on site, the design includes a sturdy and durable roof-to-wall joint that minimizes waste, insulates the interior, and locks out moisture. In addition, the design facilitates a 20-foot unsupported roof span and a 4-foot overhang beyond the exterior wall, with allowances for variation in roof pitch. The roof-to-wall joint was successfully designed and prototyped with less than half the $1200 allowable budget using galvanized steel with Expanded Polystyrene (EPS) insulation
Semantic representation of reported measurements in radiology
Background
In radiology, a vast amount of diverse data is generated, and unstructured reporting is standard. Hence, much useful information is trapped in free-text form, and often lost in translation and transmission. One relevant source of free-text data consists of reports covering the assessment of changes in tumor burden, which are needed for the evaluation of cancer treatment success. Any change of lesion size is a critical factor in follow-up examinations. It is difficult to retrieve specific information from unstructured reports and to compare them over time. Therefore, a prototype was implemented that demonstrates the structured representation of findings, allowing selective review in consecutive examinations and thus more efficient comparison over time.
Methods
We developed a semantic Model for Clinical Information (MCI) based on existing ontologies from the Open Biological and Biomedical Ontologies (OBO) library. MCI is used for the integrated representation of measured image findings and medical knowledge about the normal size of anatomical entities. An integrated view of the radiology findings is realized by a prototype implementation of a ReportViewer. Further, RECIST (Response Evaluation Criteria In Solid Tumors) guidelines are implemented by SPARQL queries on MCI. The evaluation is based on two data sets of German radiology reports: An oncologic data set consisting of 2584 reports on 377 lymphoma patients and a mixed data set consisting of 6007 reports on diverse medical and surgical patients. All measurement findings were automatically classified as abnormal/normal using formalized medical background knowledge, i.e., knowledge that has been encoded into an ontology. A radiologist evaluated 813 classifications as correct or incorrect. All unclassified findings were evaluated as incorrect.
Results
The proposed approach allows the automatic classification of findings with an accuracy of 96.4 % for oncologic reports and 92.9 % for mixed reports. The ReportViewer permits efficient comparison of measured findings from consecutive examinations. The implementation of RECIST guidelines with SPARQL enhances the quality of the selection and comparison of target lesions as well as the corresponding treatment response evaluation.
Conclusions
The developed MCI enables an accurate integrated representation of reported measurements and medical knowledge. Thus, measurements can be automatically classified and integrated in different decision processes. The structured representation is suitable for improved integration of clinical findings during decision-making. The proposed ReportViewer provides a longitudinal overview of the measurements
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