Superfluid Core Rotation in Pulsars. I. Vortex Cluster Dynamics

1995 ◽  
Vol 447 ◽  
pp. 305 ◽  
Author(s):  
Armen D. Sedrakian ◽  
David M. Sedrakian
Keyword(s):  
Core Rotation ◽  
Superfluid Core ◽  
Vortex Cluster

Superfluid Core Rotation in Pulsars. II. Postjump Relaxations

1995 ◽  
Vol 447 ◽  
pp. 324 ◽  
Author(s):  
A. D. Sedrakian ◽  
D. M. Sedrakian ◽  
J. M. Cordes ◽  
Yervant Terzian
Keyword(s):  
Core Rotation ◽  
Superfluid Core

Training in Pathology Informatics: Implementation at the University of Pittsburgh

2003 ◽  
Vol 127 (8) ◽  
pp. 1019-1025 ◽  
Author(s):  
James H. Harrison ◽  
Jimmie Stewart
Keyword(s):  
Training Model ◽  
Course Evaluation ◽  
Skill Level ◽  
Full Time ◽  
University Of Pittsburgh ◽  
Pathology Informatics ◽  
Informatics Training ◽  
Desktop Computing ◽  
Core Rotation ◽  
The University

Abstract Context.—Pathology informatics is generally recognized as an important component of pathology training, but the scope, form, and goals of informatics training vary substantially between pathology residency programs. The Training and Education Committee of the Association for Pathology Informatics (API TEC) has developed a standard set of knowledge and skills objectives that are recommended for inclusion in pathology informatics training and may serve to standardize and formalize training programs in this area. Objective.—The University of Pittsburgh (Pittsburgh, Pa) core rotation in pathology informatics includes most of these goals and is offered as an implementation model for pathology informatics training. Design.—The core rotation in pathology informatics is a 3-week, full-time rotation including didactic sessions and hands-on laboratories. Topics include general desktop computing and the Internet, but the primary focus of the rotation is vocabulary and concepts related to enterprise and pathology information systems, pathology practice, and research. The total contact time is 63 hours, and a total of 19 faculty and staff contribute. Pretests and posttests are given at the start and end of the rotation. Performance and course evaluation data were collected for 3 years (a total of 21 residents). Results.—The rotation implements 84% of the knowledge objectives and 94% of the skills objectives recommended by the API TEC. Residents scored an average of about 20% on the pretest and about 70% on the posttest for an average increase during the course of 50%. Posttest scores did not correlate with pretest scores or self-assessed computer skill level. The size of the pretest/posttest difference correlated negatively with the pretest scores and self-assessed computing skill level. Conclusions.—Pretest scores were generally low regardless of whether residents were familiar with desktop computing and productivity applications, indicating that even residents who are computer “savvy” have limited knowledge of pathology informatics topics. Posttest scores showed that all residents' knowledge increased substantially during the course and that residents who were computing novices were not disadvantaged. In fact, novices tended to have higher pretest/posttest differences, indicating that the rotation effectively supported initially less knowledgeable residents in “catching up” to their peers and achieving an appropriate competency level. This rotation provides a formal training model that implements the API TEC recommendations with demonstrated success.

scholarly journals Core rotation braking on the red giant branch for various mass ranges

2018 ◽  
Vol 616 ◽  
pp. A24 ◽  
Author(s):  
C Gehan ◽  
B. Mosser ◽  
E. Michel ◽  
R. Samadi ◽  
T. Kallinger
Keyword(s):  
Angular Momentum ◽  
Red Giants ◽  
Regular Pattern ◽  
Convective Envelope ◽  
Large Sample ◽  
The Mean ◽  
Mixed Modes ◽  
Red Giant ◽  
Core Rotation ◽  
Dipole Gravity

Context. Asteroseismology allows us to probe stellar interiors. In the case of red giant stars, conditions in the stellar interior are such as to allow for the existence of mixed modes, consisting in a coupling between gravity waves in the radiative interior and pressure waves in the convective envelope. Mixed modes can thus be used to probe the physical conditions in red giant cores. However, we still need to identify the physical mechanisms that transport angular momentum inside red giants, leading to the slow-down observed for red giant core rotation. Thus large-scale measurements of red giant core rotation are of prime importance to obtain tighter constraints on the efficiency of the internal angular momentum transport, and to study how this efficiency changes with stellar parameters. Aims. This work aims at identifying the components of the rotational multiplets for dipole mixed modes in a large number of red giant oscillation spectra observed by Kepler. Such identification provides us with a direct measurement of the red giant mean core rotation. Methods. We compute stretched spectra that mimic the regular pattern of pure dipole gravity modes. Mixed modes with the same azimuthal order are expected to be almost equally spaced in stretched period, with a spacing equal to the pure dipole gravity mode period spacing. The departure from this regular pattern allows us to disentangle the various rotational components and therefore to determine the mean core rotation rates of red giants. Results. We automatically identify the rotational multiplet components of 1183 stars on the red giant branch with a success rate of 69% with respect to our initial sample. As no information on the internal rotation can be deduced for stars seen pole-on, we obtain mean core rotation measurements for 875 red giant branch stars. This large sample includes stars with a mass as large as 2.5 M⊙, allowing us to test the dependence of the core slow-down rate on the stellar mass. Conclusions. Disentangling rotational splittings from mixed modes is now possible in an automated way for stars on the red giant branch, even for the most complicated cases, where the rotational splittings exceed half the mixed-mode spacing. This work on a large sample allows us to refine previous measurements of the evolution of the mean core rotation on the red giant branch. Rather than a slight slow-down, our results suggest rotation is constant along the red giant branch, with values independent of the mass.

Relaxation time of the superfluid core of a neutron star

Astrophysics ◽  
1997 ◽  
Vol 40 (4) ◽  
pp. 320-326
Author(s):  
D. M. Sedrakian ◽  
K. M. Shahabassian ◽  
Yu M. Bruk
Keyword(s):  
Relaxation Time ◽  
Neutron Star ◽  
Superfluid Core

Choosing Surgery: Identifying Factors Leading to Increased General Surgery Matriculation Rate

2017 ◽  
Vol 83 (3) ◽  
pp. 290-295 ◽  
Author(s):  
David T. Pointer ◽  
Matthew D. Freeman ◽  
James R. Korndorffer ◽  
Peter C. Meade ◽  
Bernard M. Jaffe ◽  
...  
Keyword(s):  
General Surgery ◽  
Role Models ◽  
Medical Student Education ◽  
Direct Result ◽  
Factors Affecting ◽  
The Past ◽  
Education Experience ◽  
Surgical Career ◽  
Core Rotation ◽  
Question Survey

Tulane graduates have, over the past six years, chosen general surgical residency at a rate above the national average (mean 9.6% vs 6.6%). With much of the recent career choice research focusing on disincentives and declining general surgery applicants, we sought to identify factors that positively influenced our students’ decision to pursue general surgery. A 50-question survey was developed and distributed to graduates who matched into a general surgery between the years 2006 and 2014. The survey evaluated demographics, exposure to surgery, and factors affecting interest in a surgical career. We achieved a 54 per cent (61/112) response rate. Only 43 per cent considered a surgical career before medical school matriculation. Fifty-nine per cent had strongly considered a career other than surgery. Sixty-two per cent chose to pursue surgery during or immediately after their surgery clerkship. The most important factors cited for choosing general surgery were perceived career enjoyment of residents and faculty, resident/faculty relationship, and mentorship. Surgery residents and faculty were viewed as role models by 72 and 77 per cent of responders, respectively. This study demonstrated almost half of those choosing a surgical career did so as a direct result of the core rotation experience. We believe that structuring the medical student education experience to optimize the interaction of students, residents, and faculty produces a positive environment encouraging students to choose a general surgery career.

Regenerator Effectiveness During Transient Operation

1994 ◽  
Author(s):  
Douglas Stephen Beck
Keyword(s):  
Heat Capacity ◽  
Steady State ◽  
Response Time ◽  
Core Material ◽  
Rotation Rates ◽  
Cool Flow ◽  
Regenerator System ◽  
Core Rotation ◽  
Time Required ◽  
Parameter Values

The transient response of regenerators is considered. The time required for regenerators to reach steady-state effectiveness is determined. Theoretical results are presented. Also, experimental results that confirm the theory are presented. It is concluded that the time required for a regenerator to reach steady-state effectiveness is τss∼NTU1+hA′1+As′CRAT4As′1-SCkN×ρcDH2RNuH1-pp This expression indicates how regenerator cores can be designed for fast effectiveness response. In dimensionless form, τXss*∼1 where τXss* is the greater of the cool-flow and warm-flow heat-capacity rates, times τss, divided by the heat capacity of the core material. This expression gives a general method for calculation of the effectiveness-response time of regenerator cores. The dimensionless response time is nearly constant with variations in regenerator system-parameter values. Also, for sufficiently high dimensionless core-rotation rates, the dimensionless response time is independent of dimensionless core-rotation rate.

scholarly journals Gravity-mode period spacings and near-core rotation rates of 611 γ Doradus stars with Kepler

2019 ◽  
Author(s):  
Gang Li ◽  
Timothy Van Reeth ◽  
Timothy R Bedding ◽  
Simon J Murphy ◽  
Victoria Antoci ◽  
...  
Keyword(s):  
Rotation Rate ◽  
Rotation Rates ◽  
The Core ◽  
Surface Rotation ◽  
Kepler Mission ◽  
Large Spread ◽  
Amplitude Spectra ◽  
Core Rotation ◽  
Composition Gradients ◽  
Gravity Mode

Abstract We report our survey of γ Dor stars from the 4-yr Kepler mission. These stars pulsate mainly in g modes and r modes, showing period-spacing patterns in the amplitude spectra. The period-spacing patterns are sensitive to the chemical composition gradients and the near-core rotation, hence they are essential for understanding the stellar interior. We identified period-spacing patterns in 611 γ Dor stars. Almost every star pulsates in dipole g modes, while about 30% of stars also show clear patterns for quadrupole g modes and 16% of stars present r mode patterns. We measure periods, period spacings, and the gradient of the period spacings. These three observables guide the mode identifications and can be used to estimate the near-core rotation rate. We find many stars are hotter and show longer period-spacing patterns than theory. Using the Traditional Approximation of Rotation (TAR), we inferred the asymptotic spacings, the near-core rotation rates, and the radial orders of the g and r modes. Most stars have a near-core rotation rate around 1 d−1and an asymptotic spacing around 4000 s. We also find that many stars rotate more slowly than predicted by theory for unclear reasons. 11 stars show rotational splittings with fast rotation rates. We compared the observed slope–rotation relation with the theory and find a large spread. We detected rotational modulations in 58 stars and used them to derive the core-to-surface rotation ratios. The interiors rotate faster than the cores in most stars, but by no more than 5%.

Healthcare Epidemiology Practicum Rotation for Postgraduate Physician Trainees in Medicine–Infectious Diseases

2013 ◽  
Vol 34 (10) ◽  
pp. 1114-1116
Author(s):  
Pranavi Sreeramoju ◽  
Maria Eva Fernandez-Rojas
Keyword(s):  
Infectious Diseases ◽  
Infection Control ◽  
Medical Center ◽  
Common Trunk ◽  
University Hospitals ◽  
Hospital System ◽  
University Of Texas ◽  
Core Rotation ◽  
The University ◽  
Healthcare Epidemiology

Practicum education in healthcare epidemiology and infection control (HEIC) for postgraduate physician trainees in infectious diseases is necessary to prepare them to be future participants and leaders in patient safety. Voss et al suggested that training in HEIC should be offered as a “common trunk” for physicians being trained in clinical microbiology or infectious diseases. A 1-month rotation has been recommended previously. A survey by Joiner et al indicated that only 50% of infectious diseases fellows found the infection control training adequate. The objective of this article is to report our 2-year experience with a 1-month practicum rotation we designed and implemented at our institution.The setting is the Adult Infectious Diseases fellowship program at the University of Texas Southwestern Medical Center (UTSW), Dallas, Texas. The fellows have clinical rotations at the Parkland Health and Hospital System, UTSW University hospitals, North Texas Veterans Affairs Health Care System, and Children's Medical Center Dallas. The 2-year program recruits 7 fellows every 2 years. The 1-month core rotation was established in July 2011 and is ongoing. Fellows who completed the rotation during the period July 2011 to April 2013 are included in this study.

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