bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of “Genetics” in Popular Understandings of Race in the United States
Authors: Condit Celeste M. , Parrott Roxanne L. , Harris Tina M. , Lynch John , Dubriwny Tasha
Published: September 2004

The increase in public representation of the science-based concept “genetics” in the mass media might be expected to have a major impact on public understanding of the concept of “race.” A model of lay understandings of the role of genetics in the contemporary United States is offered based on focus group research, random digit dial surveys, and community based surveys. That model indicates that lay people identify race primarily by physical features, but these identifications are categorized into a variety of groupings that may be regional, national, or linguistic. Although they believe that physical appearance is caused largely by genetics, and therefore that race has a genetic basis, they do not uniformly conclude, however, that all perceived racial characteristics are genetically based. Instead, they vary in the extent to which they attribute differences to cultural, personal, and genetic factors.
A Survey of Self-Care and Dependent-Care Advice Given by Pediatric Oncology Nurses
Authors: Baggott Christina , Beale Ivan L. , Dodd Marylin J. , Kato Pamela M.
Published: September 2004

This article reports a survey of the current practices of pediatric oncology nurses in advising patients and families about symptom reporting and self-care interventions. A questionnaire was mailed to 1,000 pediatric oncology nurses requesting information about age, years of experience in nursing and pediatric oncology nursing, current work setting, and professional position. Recipients were asked about their practices for advising patients and their families about self-care measures and reporting of adverse symptoms. Analysis of 135 valid responses showed evidence of both consensus and variability in nursing practice, with variability being partly attributable to differences in nurses’ work settings (inpatient vs. outpatient) and differences in experience level. There was good consensus on nurses’ recommending of several self-care interventions for eight common adverse symptoms and for advice that patients should promptly report to health providers certain symptoms or events.
Psychosocial Adjustment of Adolescent Siblings of Hematopoietic Stem Cell Transplant Patients
Authors: Packman Wendy , Gong Kimberly , VanZutphen Kelly , Shaffer Tani , Crittenden Mary
Published: September 2004

Hematopoietic stem cell transplantation (HSCT) is a widely practiced therapy for many life-threatening childhood disorders. The authors investigated the psychosocial effects of HSCT on siblings of pediatric HSCT patients ( n = 44; 21 donors, 23 nondonors, ages 6 to 18 years). Donor siblings reported significantly more anxiety and lower self-esteem than did nondonors. Nondonors showed significantly more school problems. Approximately one third of all siblings reported moderate to severe posttraumatic stress. The study drew on the developmental theory of Erik Erikson and the psychosocial model of posttraumatic stress. As part of the study, the authors used the Measures of Psychosocial Development (MPD), a self-report measure based on Eriksonian constructs. The MPD was used to assess the psychosocial adjustment of 12 siblings who were adolescents (≥ 13 years) at the time the study was conducted. In this article, findings are presented from the MPD as well as salient findings from the larger study.
Prevention and Treatment of Mucositis: A Guide for Nurses
Authors: Wohlschlaeger Anne
Published: September 2004

Oral mucositis is a frequent and potentially severe complication that can occur following chemotherapy or irradiation. Not only is mucositis painful but it can also result in impaired nutrition, infection, and treatment delays. Pediatric oncology nurses have a challenge to try to provide the most appropriate mouth care regimen specific to each individual patient. This review of the literature can serve as a guide for helping to prevent and to treat mucositis. It provides information about the chemotherapeutic agents responsible for causing mucositis, many of the preventive approaches used to reduce the incidence of mucositis, and the current treatments available for active mucositis. It also discusses dietary recommendations and the role of the nurse caring for the patient with mucositis.
Quality of Life Among Children With Sickle Cell Disease Receiving Chronic Transfusion Therapy
Authors: Stegenga Kristin A. , Ward-Smith Peggy , Hinds Pamela S. , Routhieaux Julie A. , Woods Gerald M.
Published: September 2004

Sickle cell disease (SCD) is a genetic disorder that is most prevalent among those of African American and Mediterranean descent. Hemoglobin SS is the most severe form of SCD and carries an increased risk for stroke. Although the initial treatment for stroke is an exchange transfusion, the use of routine, chronic transfusion therapy (CTT) has been shown to help prevent this neurological injury. The treatment plan is rigorous and time consuming, both of which impact one’s quality of life (QoL). The purpose of this study was to explore QoL, from the child’s perspective, as it is affected by CTT. Semistructured interviews were performed on 10 children undergoing CTT. Five themes emerged from the data: (a) pain, (b) school issues, (c) disease knowledge, (d) transfusion therapy, and (e) having a stroke. Data from this study reveal that CTT does have an impact on QoL. This information is important to share with those making CTT treatment decisions.
Parental Views of the Social Environment of an Outpatient Bone Marrow Transplant Clinic
Authors: Pritchett Jennifer K. , Buckner Ellen B.
Published: September 2004

The purpose of this project was to investigate, through the eyes of the parents, the social environment of the outpatient bone marrow transplant (BMT) clinic. The BMT clinic provides children with posttransplant treatment and emergency care. The clinic consists of an open room with eight patient chairs where the staff can assess and treat the patients. Via investigator-designed questionnaires, 17 participants responded to items on the variables of comparison to traditional settings, privacy, comparison with other children, and social support. Content validity was established through review by nurse clinicians. Findings indicated that the parents preferred the environment of this clinic to traditional clinics and that the informal social support they and their children received while in the waiting room was a main strength. However, parents also identified negative aspects of comparing their children to others and lack of privacy. Overall, the parents reported the advantages of this clinic outweighed the possible negative aspects. Results indicated that the setting studied has the ability to foster a social environment complementary to the technical aspects of medical care.
A Comparison of Calorie and Protein Intake in Hospitalized Pediatric Oncology Patients Dining With a Caregiver Versus Patients Dining Alone: A Randomized, Prospective Clinical Trial
Authors: Williams Ruth , Hinds Pamela S. , Ke Weiming , Hu X. Joan
Published: September 2004

Hospitalization and cancer therapy can contribute to decreased food intake in children and adolescents with cancer, making it a challenge to meet their nutritional needs. The affect of hospitalization and the eating environment for pediatric oncology patients has not been studied very well, and the effect of altering the social aspect of mealtime for hospitalized pediatric oncology patients has not been studied at all. The authors conducteda randomized, prospective clinical trial to determine if hospitalized pediatric oncology patients consume more protein and calories when eating with afamily member or when eating alone in their room at mealtime. All food and beverage intake was recorded for 3 consecutive days, and a food service satisfaction survey was completed on Day 3. Food records were analyzed for calorie and protein intake, and surveys were analyzed for patient/parent satisfaction. The study was completed by 200 hospitalized patients and their parent/caregiver. Overall, neither calorie nor protein intake differed significantly between the two groups, but patient/parent satisfaction was significantly higher in the group of patients who dined with their caregiver. By using analysis of variance, the authors found that ideal body weight and years of sickness were significantly associated with calorie and protein intake.
Improving Pediatric Chemotherapy Safety Through Voluntary Incident Reporting: Lessons From the Field
Authors: France Daniel J. , Cartwright Julia , Jones Vicki , Thompson Vicky , Whitlock James A.
Published: September 2004

Background: A multidisciplinary team within Vanderbilt Children’s Hospital (VCH) designed, developed, and implemented a pediatric chemotherapy incident reporting and improvement system (CIRIS) for pediatric oncology nurse and pharmacists. The aim of this collaboration was to improve pediatric chemotherapy by translating recommendations made by the Institute of Medicine into an operational safety improvement system that is embedded into daily care processes. Methods: CIRIS improves chemotherapy safety by linking two distinct components: (a) a technical component that uses desktop, laptop, and portable wireless handheld computers to interface the Web-based software application for point-of-care incident reporting and on-demand retrieval of patient support information, and (b) a human component that performs process analysis, data reporting, and clinical improvement. This integrated system facilitates and supports a blame-free culture for reporting of near misses and preventable adverse drug events. Results: Between February 8, 2002, and March 9, 2003, pediatric oncology nurses and chemotherapy pharmacists electronically reported 97 chemotherapy-related incidents associated with 96 unique patients. Ordering errors were the most commonly reported incidents. CIRIS improved reporting performance demonstrated using the conventional paper-based reporting system.
Physical Restraint during Procedures: Issues and Implications for Practice
Authors: Tomlinson Deborah
Published: September 2004

Physical restraint or holding down a child or young person with cancer is generally accepted to ensure success in carrying out the various procedures involved throughout the disease trajectory. Over the past several years, health care staff have become more aware of the issues surrounding physical restraint. However, the research around the effects of being involved in physical restraint is extremely limited. Nurses continue to have little education in the pertinent issues, restraint techniques, and alternative strategies. This article aims to highlight areas that nurses caring for children and young people with cancer need to consider. Strategies for improving practice are also discussed with the thought that nurses will be stimulated to re-evaluate the use of physical restraint in this group of children and young people.
The Adolescent Resilience Model as a Guide to Interventions
Authors: Haase Joan E.
Published: September 2004

Adolescents with cancer (AWC) are a neglected population in the area of psychosocial services, and little theoretically based research has been conducted on interventions to help them positively adjust to the cancer experience. In addition, although knowledge of how individuals positively adjust to difficult life circumstances can provide important guidance for developing effective interventions, research has underemphasized positive health and overemphasized pathology models in addressing psychosocial adjustment of AWC. Theories focusing on positive health concepts such as resilience are potentially excellent guides for developing effective psychosocial interventions, because the factors that influence positve health, such as hope, positive coping, and perceived social support, are amenable to improvement. The Adolescent Resilience Model (ARM) is one of the first theoretical models to propose a comprehensive, integrative representation of the process and outcomes of resilience and quality of life in AWC. The ARM is an example of a theory-driven research program that aims to improve outcomes for AWC by focusing on positive health concepts. Presented here are the underlying theoretical perspectives, variables in the ARM, and the ways the ARM may be used to guide interventions aimed at improving short- and long-term outcomes for AWC.
The Adolescent Resilience Model and Interventions to Promote Resilience-Critique
Authors: Clarke-Steffen Laura
Published: September 2004

This critique will further explore Dr Haase’s work on interventions to enhance resilience in adolescents with cancer, focusing on the clinical aspects of the Resilience Enhancement Adolescent Profile (REAP) intervention. To summarize, the REAP intervention is composed of (a) development of an individualized family and adolescent profile near the time of diagnosis; (b) standardized, multidisciplinary review of the profile with development of a care plan; and (c) a series of 6 sessions with the adolescent and the family if the adolescent desires. The first session includes presentation of the profile and care plan to the adolescent and the family. Subsequent sessions focus on specific protective factors.
The Adolescent Resilience Model and Interventions to Promote Resilience—Critique
Authors: Kupst Mary Jo
Published: September 2004

Dr Joan Haase has paid meticulous attention to methodology in the frequently hazy area of coping and resilience. More important, her emphasis is on the positive side of coping and adaptation. Her work has many strengths. Although the author of this article will discuss points specific to the Adolescent Resilience Model (ARM), the questions are for all of us who struggle to make sense of the way people cope, why some are more resilient than others, and how to strengthen coping and resilience.
Facilitating Care for Childhood Cancer Survivors: Integrating Children’s Oncology Group Long-Term Follow-Up Guidelines and Health Links in Clinical Practice
Authors: Eshelman Debra , Landier Wendy , Sweeney Teresa , Hester Allison L. , Forte Kathy , Darling Joan , Hudson Melissa M.
Published: September 2004

Childhood cancer survivors are a growing, vulnerable group with health care needs unique to their cancer treatments. They may experience many late physical and psychological complications (late effects) of treatment including organ dysfunction, infertility, second neoplasms, chronic hepatitis, musculoskeletal problems, alterations in cognitive function, and myriad psychosocial problems. Health care providers may be unaware of actual or potential survivor problems. Until recently, there were no clearly defined, easily accessible risk-based guidelines for cancer survivor follow-up care. This article will use a case-study approach to demonstrate how the newly developed Children’s Oncology Group Long-term Follow-up Guidelines and Health Links can be used in clinical practice to improve awareness about late effects and the importance of follow-up care for childhood cancer survivors. The Children’s Oncology Group Guidelines and Health Links were created by a multidisciplinary team of health care experts and patient advocates to provide a systematic plan for pediatric cancer survivor follow-up care and health education across the cancer continuum.
A Cost-Effective Scheme to Improve Radial Tracking Performance for Higher-Speed Optical Disk Drives
Authors: Zhou Yu , Steinbuch Maarten , Leenknegt George
Published: September 2004

The periodic disturbances caused by the inherent eccentricity and unbalancing in compact disk systems is one of the prominent radial-tracking problems of high-speed and high-density optical storage systems. To compensate these periodic disturbances, an adaptive feedforward compensation technique is presented and investigated with the aim of having cost-effective optical disk drive manufacturing. Computer simulations and experimental evaluation on a high-speed CD-ROM product show that the proposed adaptive feedforward compensator is very effective and provides a way to significantly improve the radial tracking performance by reducing the radial error by 85%.
Performance Verification of Semi-Active and Active Impact Control Systems
Authors: Kim Dong Hwan , Choi Moon-Chul , Baek Joo-Hoon
Published: September 2004

A semi-actively controlled impact systemis studied, which adjusts an impulse exerted by the external impact. Also, an active impact control system using a servo valve is introduced, and these performances are compared. The systems should respond to the extremely short impulse and control the impulse within a highly fast interval. Both the semi-active and the active control systems utilize an external orifice in the form of a proportional valve or a servo valve, which adjusts its opening area to control the pressure and piston displacement. These devices overcome the temperature and viscosity variations due to continuant operations, and keep the desired pressure difference and the displacement at a desirable level. In this work, two prototypic impact systems controlled by semi-active and full active operations are designed and manufactured. Through computer simulations and experiments, the possibility of controlling the pressure and displacement of an impact control system is verified.
Nonlinear Tracking Control of an Elastically Supported Flapping Thin Airfoil
Authors: Al-Majed Mohammed I. , Alsaif Khalid A.
Published: September 2004

A control law for a self-excited system using state feedback linearization and coordinate transformation is developed. The system consists of an elastically supported hinged thin airfoil, which is subjected to a uniform steady airflow A nonlinear aerodynamic model is used to account for the fluid-solid interaction mnechanism. A chaotic behavior of the open-loop system at certain control parameters is observed experimentally and checked numerically. It is shown that the controllability of the system is guaranteed using a torque source at the leading edge of the airfoil. Furthennore, good tracl4rg of time-varying desired angle of attack is achieved using the developed controller. Finally, a SIMULINK%N model is developed to facilitate time-domain analysis, control design and future real-time control implementations.
Spectral Confonning Model and Its Application
Authors: Shim Jaeho , Ram Ym.
Published: September 2004

It has been observed that finite elem-ent or finite difference models of order n can approximate with fair accuracy less than one-third of the eigenvalues of the underlying continuous system corresponding to the low spectrum. We present a new spectral conforming discrete model that estimates n the lowest eigenvalues of the continuous system with uniform accuracy. The building block of the model is the fundamental inverse eigenvalue problem of reconstructing the chain of a mass-spring system with a prescribed spectrum. We present applications of the model in vibration control of continuous systems by using small-order spectral conformning models, and spectrum estimation of non-uniform systems.
Vibration and Acoustic Noise Characterization of a Gradient Coil Insert in a 4 T MRI
Authors: Mechefske Chris K. , Yao G. , Wang Fenglin
Published: September 2004

High magnetic field strength and high-speed gradient coil current switching are becoming ever more commonplace in magnetic resonance imaging scanners. These and other factors are combining to yield high acoustic sound pressure levels (SPLs) in and around magnetic resonance imagers. Studies have already been conducted which partially characterize this sound field, and various methods have been investigated to attenuate the noise generated. In order to predict the vibration and acoustic response of a gradient coil inside a scanner, finite element analysis (FEA) was carried out. The model was based on specific internal and external structural dimensions and the material physical properties of a gradient coil. The FEA results were verified through experimental modal testing of the same gradient coil. It was found that the experimental modal analysis results were in good agreement with the FEA results. The Lorentz force distribution on the gradient coil caused by the time varying current in the coil windings was then applied to the FEA model to obtain the velocity distribution of the coil surface as a function of time. A vibro-acoustic computational model was then developed based on the verified FEA model. The surface velocity distribution was then used to predict the sound field inside the gradient coil. The vibro-acoustic model was verified using experimental noise measurements with swept sinusoidal waveform inputs to the gradient coil conductors. The numerical methods developed in this study could provide a guide and virtual testing platform for the designer of gradient coils to predict the vibration and acoustic behavior of new designs and thereby offer the opportunity to redesign and/or optimize the design to reduce SPLs.
Simulation and Experimental Research of the Grinder'S Wheelhead Dynamics
Authors: Oryński Franciszek , Pawłowski Witold
Published: September 2004

In this paper we present a simulation based on the physical model of a cylindrical, plunge grinder with hydrostatic slideways and hydrostatic bearings of a grinding wheel spindle. The simulation was carried out in order to check the influence of the grinding process on the forced vibration damping of the wheelhead. The experimental research was undertaken to verify the idea of the damping facility of the grinding process. The results of the experiments and the simulation were used to draw the final conclusions.
Experimental Modal Analysis of Steel Concrete Composite Beams with Partially Damaged Connection
Authors: Dilena Michele , Morassi Antonino
Published: September 2004

One of the main difficulties connected with the use of dynamic methods for damage detection in structures lies in the small sensitivity of the dynamic parameters to damage. This is an intrinsic feature of structural diagnostics based on dynamic data and represents a source of important indeterminacy, such as the strong dependence of the results of damage detection techniques on the experimental errors and on the accuracy of the structural model that is chosen to interpret measurements. These facts are nowadays well known for simple structural systems, such as single beams or frames, but still are not completely clarified for more complicated structures. In this paper we present and discuss the results of an experimental investigation on the sensitivity of modal parameters of steel-concrete composite beams with partially damaged connection. Dynamic tests were performed on two pairs of composite beams, whose connecdons have different linear densities, and four damage configurations for each beam were analyzed. Damage corresponds to a symmnetric notch of increasing depth induced by saw-cutting one end-connector of the composite beam. Natural frequencies and modal damping of the lower axial and flexural modes were assessed for the undamaged configuration and the four levels of damage. Flexural vibrating modes were assessed up to the fourth-order mode.
An Idea of Applying μ-Synthesis to Launcher Attitude and Vibration Control Design
Authors: Morita Yasuhiro
Published: September 2004

This paper presents a methodology for applying μ-synthesis to a real high-order system: launch vehicle attitude and vibration control. The design involves robust characteristics against uncertainties of the system parameters as well as precise tracking performance under limited rigidity. As the plant dynamics has an extremely high order and unstable character, the standard μ-synthesis cannot be directly applied. Thus, the standard procedure is modified in a specialway in order tomake the approach more efficient. The methodology provided in the study will contribute to a better understanding of how to apply the robust control theory to complicated real problems.
Autonomous Overhead Crane System Using a Fuzzy Logic Controller
Authors: Omar F. , Karray F. , Basir O. , Yu L.
Published: September 2004

This paper pertains to advanced automation of the load transfer process using overhead cranes. Overhead cranes are widely used in various areas of industry, including manufacturing, construction, shipping, etc. Load transfer operations using overhead cranes have to be performed fast and safely. As such, these operations are handled by expert operators however, the demand for an automatic consistent and reliable crane operation is on the rise. The crane–load system is highly nonlinear and time-varying, hence, solutions considering model-base approaches may lead to a complicated controller structure. Such a controller may require accurate estimation of the crane system parameters. In this paper we present a new fuzzy logic controller for overhead crane operation. The fuzzy controller is designed based on knowledge of an expert crane operator, and does not require any parameter estimation. It mimics the operator behavior by using the same crane–load system states that are realized by the operator. These states are the trolley position error and the load sway angle. The fuzzy controller action, on the other hand, is the desired trolley speed. The proposed controller is implemented and tested on a small-scale overhead crane. Experimental results show robust operation of the fuzzy controller as compared with that of a conventional controller.
Attitude Control of a Spacecraft with Two Reaction Wheels
Authors: Urakubo Takateru , Tsuchiya Kazuo , Tsujita Katsuyoshi
Published: September 2004

This paper deals with the attitude control of a rigid spacecraft with two reaction wheels. First, we derive a discontinuous state feedback law based on Lyapunov control. The control input is obtained by multiplying the gradient vector of the Lyapunov function by a matrix that is composed of a symmetric matrix and an asymmetric one. Under this method, when the angular momentum of the system is zero, the desired point is the only stable equilibrium point of the controlled system. Next, we investigate the behavior of the controlled system when the angular momentum of the system is not zero but small. In this case, the system converges to either a limit cycle or an equilibrium point which is not the desired point however, in both cases, the error in attitude remains small.
Nutation Damper Undergoing a Coupled Motion
Authors: Lu M. L. , Popplewell N. , Shah A. H. , Chan J. K.
Published: September 2004

A novel numerical model is proposed to simulate liquid sloshing in a rectangular nutation damper (i.e. a tuned liquid damper) undergoing a coupled horizontal and rotational motion. Shallow water theory is used consistently to derive the governing equations of motion so that the model is applicable to large sloshing involving a hydraulic jump. It can also accommodate exposure of part of the damper’s floor to air by using a somewhat improved boundary shear approximation. A simple finite difference approach – the Lax scheme – is found to solve the equations of motion surprisingly well. Numerical predictions are checked against limited experimental data for a purely horizontal motion. Good agreement is generally observed. Furthermore, to demonstrate the model’s broader scope, the effect of a rotation is also considered in conjunction with a horizontal motion. The rotation is shown to significantly enhance the damper’s energy dissipation and, hence, its attenuation capability. For convenient practical application, an equivalent singledegree-of-freedom oscillator model is presented to characterize a nutation damper’s behavior for a coupled motion. The equivalent parameters of the model are determined so that the dissipated energy “best” fits a numerical counterpart. Their effect is investigated for different lengths, depths, and vibration levels of the damper. While the motivation of this investigation is to control the wind-induced galloping of overhead power lines, the proposed approach is applicable more generally to any excitation that induces low frequency vibrations.
Variable-Gain Constraint Stabilization for General Multibody Systems with Applications
Authors: Nagata Takashi
Published: September 2004

This paper presents a general and efficient formulation applicable to a vast variety of rigid and flexible multibody systems. It is based on a variable-gain error correction with scaling and adaptive control of the convergence parameter. The methodology has the following distinctive features. (i) All types of holonomic and non-holonomic equality constraints as well as a class of inequalities can be treated in a plain and unified manner. (ii) Stability of the constraints is assured. (iii) The formulation has an order Ncomputational cost in terms of both the constrained and unconstrained degrees of freedom, regardless of the system topology. (iv) Unlike the traditional recursive order Nalgorithms, it is quite amenable to parallel computation. (v) Because virtually no matrix operations are involved, it can be implemented to very simple general-purpose simulation programs. Noting the advantages, the algorithm has been realized as a C++ code supporting distributed processing through the Message-Passing Interface (MPI). Versatility, dynamical validity and efficiency of the approach are demonstrated through numerical studies of several particular systems including a crawler and a flexible space structure.
Prospects for the Suppression of Aeroedynamic Vibrations of a Long-Span Bridge Using Boundary-Layer Control
Authors: Kubo Yoshinobu
Published: September 2004

Aerodynamic vibrations inherently occur on a long-span-length bridge. The vibrations are roughly classified into vortex-excited vibration and self-excited vibration both are induced by separation flow from the leading edge of the structure. As aerodynamic vibrations frequently cause fatal damage to the structure, the suppression method of vibration has been studied for a long time. Two methods have been proposed for suppression of the vibrations: a structural method and an aerodynamic method. The former is a tuned mass damper or a tuned liquid damper, and the latter is a separation flow control using a certain device of flap or faring. As the aerodynamic method is one of the solutions to eliminate the cause of aeroelastic vibration, the aerodynamic method is more useful than the structural method from the point of view of the suppression of vibrations. Sometimes, however, it may be more costly. This paper deals with the prospects for active control of separation flow to suppress vibrations for the girders and towers of a long-span-length bridge.
Instantaneous Optimal Control of Seismically-Excited Structures Using a Maximum Principle
Authors: Tarantino J. , Bruch J. C. , Sloss J. M.
Published: September 2004

An optimal control scheme is proposed for linear dynamic system models, and the optimal control forces are derived using a maximum principle. Numerical examples are presented demonstrating the characteristics of the control scheme. An instantaneous extension to the optimal control method is proposed to deal with the unknown nature of seismic disturbances. Examples of the effectiveness of the method and a tradeoff curve are presented.
Numerical Simulations of Vibration Attenuation of High-Speed Train Foundations With Varied Trackbed Underlayment Materials
Authors: Wang Judith , Zeng Xiangwu
Published: September 2004

Interest in high-speed railway as an alternative means of transportation is steadily increasing around the world. However, high-speed trains come with the concern of track vibration and induced noise and ground vibration. Excessive track vibration can cause damage to trains and tracks and reduce riding comfort for passengers. Ground vibration induced by passing trains can also damage and disturb surrounding infrastructure (especially structures housing precision machines or instruments) and residents. One potential solution toward minimizing these vibrations is the use of rubber-modified asphalt concrete (RMAC) as a material for high-speed train trackbed underlayments. In this paper we present the results of a finite element simulation of a high-speed train foundation. The simulated foundation was subjected to dynamic loading in several test scenarios, with RMAC and other traditional paving materials used as trackbed underlayment materials. The ground accelerations at designated points in these simulations were then monitored and compared with one another to determine the relative effectiveness in vibration attenuation. From these parametric studies, RMAC proves to be more effective than currently used paving materials in damping out vibrations from dynamic loading. Implications for field applications are also discussed.
Low Power Consumption Nonlinear Control with H∞ Compensator for a Zero-Bias Flywheel AMB System
Authors: Sivrioglu S. , Nonami K. , Saigo M.
Published: September 2004

A nonlinear control approach based on a control current switching rule is studied experimentally for an energy storage flywheel active magnetic bearing (AMB) system. In the proposed control, only one electromagnet in each axis of the AMB has a current flow at any given time, depending on the rotor displacement. This results in a power consumption that is lower than a linear control employing a bias current. The equation of motion for the rigid rotor-AMB system is transformed to have a decentralized structure for the control design. To compute nonlinear control currents, an H ∞ compensator is designed for each axis of the AMB. The proposed approach is experimentally verified using a high-speed digital signal processor.
A Low-Order H∞ Controller Design for an Active Suspension System via Linear Matrix Inequalities
Authors: Amirifar R. , Sadati N.
Published: September 2004

We present an application of a new controller order reduction technique with stability and performance preservation based on linear matrix inequality optimization to an active suspension system. In this technique, the rank of the residue matrix of a proper rational approximation of a high-order H ∞ controller subject to the H ∞-norm of a frequency-weighted error between the approximated controller and high-order H ∞ controller is minimized. However, since solving this matrix rank minimization problem is very difficult, the rank objective function is replaced with the nuclear-norm that can be reduced to a semidefinite program, so that it can be solved efficiently Application to the active suspension system of the Automatic Laboratory of Grenoble provides a fourth-order controller. The experimental results show the control specifications are met to a large extent.
What Matters to Low-Income Patients in Ambulatory Care Facilities?
Authors: Delia Derek , Hall Allyson , Prinz Timothy , Billings John
Published: September 2004

Poor, uninsured, and minority patients depend disproportionately on hospital outpatient departments (OPDs) and freestanding health centers for ambulatory care. These providers confront significant challenges, including limited resources, greater demand for services, and the need to improve quality and patient satisfaction. The authors use a survey of patients in OPDs and health centers in New York City to determine which aspects of the ambulatory care visit have the greatest influence on patients’ overall site evaluation. The personal interaction between patients and physicians, provider continuity, and the general cleanliness/appearance of the facility stand out as high priorities. Access to services and interactions with other facility staff are of significant, although lesser, importance. These findings suggest ways to restructure the delivery of care so that it is more responsive to the concerns of low-income patients.
Increasing Value: A Research Agenda for Addressing the Managerial and Organizational Challenges Facing Health Care Delivery in the United States
Authors: Shortell Stephen M.
Published: September 2004

There is growing consensus that the U.S. health care system is not producing value relative to the resources invested. Unwarranted variation exists in quality and outcomes of care and underutilization of both evidence-based medicine and evidence-management practices. To address these issues, this article calls for a broad-based social science approach focused on obtaining a greater understanding of change at the individual, group, organizational, and environmental levels as they influence each other. Specific examples and questions for research are suggested with regard to the redesign of care systems, enhancing learning and transferring knowledge, and creating effective financial incentives. The specific measurement, analysis, and study design issues involved in under-taking such a research agenda are discussed.
Penetrating the “Black Box”: Financial Incentives for Enhancing the Quality of Physician Services
Authors: Conrad Douglas A. , Christianson Jon B.
Published: September 2004

This article addresses the impact of financial incentives on physician behavior, focusing on quality of care. Changing market conditions, evolving social forces, and continuing organizational evolution in health services have raised societal awareness and expectations concerning quality. This article proceeds in four parts. First, the authors place financial incentives in the context of broader forces shaping the quality of physician services. Second, the article reviews the literature on financial incentive effects on physician behavior. Third, a simple net income maximization model of physician choices is presented, from which are derived formal hypotheses regarding the effect of financial incentives on physician choices of quality per unit of physician service and the quantity of services per patient. The model is extended qualitatively to offer further hypotheses and research directions. Finally, gaps and limitations of the model and of the extant empirical research are articulated, and additional researchable questions are posed.
Primary Care Outcomes in Patients treated by Nurse Practitioners or Physicians: Two-Year Follow-Up
Authors: Lenz Elizabeth R. , Mundinger Mary O’Neil , Kane Robert L. , Hopkins Sarah C. , Lin Susan X.
Published: September 2004

This study reports results of the 2-year follow-up phase of a randomized study comparing outcomes of patients assigned to a nurse practitioner or a physician primary care practice. In the sample of 406 adults, no differences were found between the groups in health status, disease-specific physiologic measures, satisfaction or use of specialist, emergency room or inpatient services. Physician patients averaged more primary care visits than nurse practitioner patients. The results are consistent with the 6-month findings and with a growing body of evidence that the quality of primary care delivered by nurse practitioners is equivalent to that by physicians.
Severity of Illness and Ambulatory Care–Sensitive Conditions
Authors: Yuen Elaine J.
Published: September 2004

This study describes how severity of illness may refine the definition of ambulatory care–sensitive conditions, or ACSCs. Hospital discharge abstract data from Philadelphia were combined with census data to develop population-based adjusted rates of hospitalization for diabetes and asthma, two ACSCs. By stratifying ACSC hospitalization by severity of illness, variations were observed by age, race, and gender. Minority groups may be at higher risk for less access to outpatient primary care and were observed to have higher rates of more severely ill, Stage 3 hospitalization. Geographic map displays indicated wide ranges of age-sex-adjusted rates for high-severity hospitalization in the five-county Philadelphia region. This refined ACSC measure may help to identify specific groups and clinical conditions within a population to assist health care planners estimate health care resources such as facilities, manpower, and programs, as well as to evaluate their outcomes.
How Health Policy and Health Services Researchers are Compensated: Analysis of a Nationwide Salary Survey
Authors: Resneck Jack , Luft Harold
Published: September 2004

The membership of Academy Health, a professional organization, was invited to complete an anonymous Web-based survey in 2002. Responses were received from 1,140 of 2,633 surveyed (43 percent). Fifty-six percent worked in academic institutions or teaching hospitals, 34 percent in the private sector or foundations, and 10 percent in government. Most (96 percent) had at least one advanced degree, and the diversity of educational backgrounds was pronounced. The median annual salary was $99,000. Salaries were highest in the private sector, followed by academic and government settings. There were large regional variations, with higher salaries in the Mid-Atlantic and New England regions. Adjusted data suggested these higher regional salaries were inadequate to compensate for higher local cost of living. Among academic respondents, nonadjusted salaries increased with advancing faculty job titles, but this seniority effect was inconsistent across geographic regions. Junior faculty salaries, when adjusted for cost of living, were more similar across regions than salaries at the full professor level.
Assessing the Influence of Incentives on Physicians and Medical Groups
Authors: Town Robert , Wholey Douglas R. , Kralewski John , Dowd Bryan
Published: September 2004

This article describes issues that should be considered in the development of a theory or theories about incentives from which testable hypotheses could be derived. Economic, psychological, and organizational theories are described, and issues that should be considered in hypothesis generation are presented. Psychological factors influencing incentives include decision framing, regret, heuristics, and reinforcements. Organizational factors influencing incentives include bundling of services or people, matching of incentive structure with work organization, and the incompletely contained hierarchical nesting of incentives. Finally, the dynamics of incentive change are considered, with a focus on describing the conditions under which physicians and physician organizations respond to incentive changes.
Opportunities and Challenges for Measuring Cost, Quality, and Clinical Effectiveness in Health Care
Authors: Fishman Paul A. , Hornbrook Mark C. , Meenan Richard T. , Goodman Michael J.
Published: September 2004

Empirical studies of health care cost, productivity, and output have focused primarily on intermediate goods and services. Consumers are ultimately interested in final goods such as improved health or health-related quality of life, but health services research continues to address whether health services financing and delivery are structured in ways to maximize production of intermediate goods, regardless of the link between these services and final outcomes. Increasing rates of growth of health care cost and dissatisfaction with the quality of U.S. health care force us to reexamine how productivity and cost are analyzed so that research properly informs policy and practice. The authors examine recent changes in the U.S. health care sector that suggest the need to revise how health services research approaches analyses of cost, production, and output; consider alternative notions of final goods; and review the availability and quality of data necessary to conduct this research.
Conceptualizing Youth Empowerment within Tobacco Control
Authors: Holden Debra J. , Messeri Peter , Evans W. Douglas , Crankshaw Erik , Ben-Davies Maureen
Published: September 2004

This article presents a conceptual framework that was developed to guide a national evaluation of the American Legacy Foundation’s (Legacy) Statewide Youth Movement Against Tobacco Use (SYMATU) program. This program was designed to develop youth-led, youth-directed initiatives within local communities. Two evaluation studies were designed and implemented from 2000 through 2003: a cross-site study that collected standard data elements across all 17 programs and a case study of five programs that collected formative data on variables thought to affect program implementation. In developing the youth empowerment (YE) conceptual framework, the authors started by reviewing literature to identify the concepts necessary for these types of initiatives and present a summary of their findings here. This article focuses on the development of the authors’overarching conceptual framework used to guide their evaluation studies. Other articles contained within this special issue present results from each of the SYMATU evaluation studies.
Adult and Group Influences on Participation in Youth Empowerment Programs
Authors: Evans W. Douglas , Ulasevich Alec , Blahut Stephen
Published: September 2004

This study examined adult and group influences on youth participation in youth empowerment (YE) Statewide Youth Movement Against Tobacco Use programs. Adults provide individual guidance to youth groups and through existing tobacco control networks affect the social context in which YE programs are implemented. The authors tested hypotheses about the direct and indirect relationships between adults, groups, and youth collective participation. They used data from adults and youths to develop a measurement model of four higher order factors: adult involvement, group structure, group climate, and collective participation. They tested relationships between these factors in a structural equation model. Results showed that adult involvement did not have a meaningful direct effect on group factors or collective participation. Group factors mediated the relationship between adult involvement and collective participation. Further research is needed on how to measure adult involvement and its relationship to youth participation.
Examination of the Relationship between Community Support and Tobacco Control Activities as a Part of Youth Empowerment Programs
Authors: Hinnant Laurie W. , Nimsch Christian , Stone-Wiggins Brenda
Published: September 2004

Through the American Legacy Foundation’s Statewide Youth Movement Against Tobacco Use (SYMATU), programs aimed at empowering youths to take action against tobacco use were funded. It is believed that the activities these groups undertake result in changes at the community level. This article examines the relationships between community support of tobacco control and the number and types of tobacco control-related activities these local youth groups conduct. Regression analyses examine the influence that different levels and sources of community support have on the quantity and focus of a group’s activities. The influences of community support are briefly explored to understand if certain group characteristics have an impact on the quantity or sources of support for tobacco control. A deeper understanding of the importance and impact of community support will help groups understand the need for building community support networks and how these networks can assist them with implementation of program activities.
Personality and Disease: Correlations of Multiple Trait Scores with Various Illnesses
Authors: Yousfi S. , Matthews G. , Amelang M. , Schmidt-Rathjens C.
Published: September 2004

Correlations between personality measures and self-reported data on health status were examined in a sample of 5133 men and women, aged between 40 and 65. A wider range of diseases was studied than is typical. Small but theoretically meaningful correlations with personality were found for some diseases. Personality syndromes of Emotional Lability, Type A Behaviour, Behavioural Control, Locus of Control over Diseases and Psychoticism were distinguished factorially. Emotional Lability appeared to be the most robust predictor of general disease vulnerability. Some small but significant associations between specific illnesses and Type A and Behavioural Control were also found.