bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improving Patient Safety in Hospitals: Contributions of High‐Reliability Theory and Normal Accident Theory
Authors: Tamuz Michal , Harrison Michael I. 
Published: June 2006

Objective. To identify the distinctive contributions of high‐reliability theory (HRT) and normal accident theory (NAT) as frameworks for examining five patient safety practices.Data Sources/Study Setting. We reviewed and drew examples from studies of organization theory and health services research.Study Design. After highlighting key differences between HRT and NAT, we applied the frames to five popular safety practices: double‐checking medications, crew resource management (CRM), computerized physician order entry (CPOE), incident reporting, and root cause analysis (RCA).Principal Findings. HRT highlights how double checking, which is designed to prevent errors, can undermine mindfulness of risk. NAT emphasizes that social redundancy can diffuse and reduce responsibility for locating mistakes. CRM promotes high reliability organizations by fostering deference to expertise, rather than rank. However, HRT also suggests that effective CRM depends on fundamental changes in organizational culture. NAT directs attention to an underinvestigated feature of CPOE: it tightens the coupling of the medication ordering process, and tight coupling increases the chances of a rapid and hard‐to‐contain spread of infrequent, but harmful errors.Conclusions. Each frame can make a valuable contribution to improving patient safety. By applying the HRT and NAT frames, health care researchers and administrators can identify health care settings in which new and existing patient safety interventions are likely to be effective. Furthermore, they can learn how to improve patient safety, not only from analyzing mishaps, but also by studying the organizational consequences of implementing safety measures.
Fair and Just Culture, Team Behavior, and Leadership Engagement: The Tools to Achieve High Reliability
Authors: Frankel Allan S. , Leonard Michael W. , Denham Charles R. 
Published: June 2006

Background.Disparate health care provider attitudes about autonomy, teamwork, and administrative operations have added to the complexity of health care delivery and are a central factor in medicine's unacceptably high rate of errors. Other industries have improved their reliability by applying innovative concepts to interpersonal relationships and administrative hierarchical structures (Chandler 1962). In the last 10 years the science of patient safety has become more sophisticated, with practical concepts identified and tested to improve the safety and reliability of care.Objective.Three initiatives stand out as worthy regarding interpersonal relationships and the application of provider concerns to shape operational change: The development and implementation of Fair and Just Culture principles, the broad use of Teamwork Training and Communication, and tools like WalkRounds that promote the alignment of leadership and frontline provider perspectives through effective use of adverse event data and provider comments.Methods.Fair and Just Culture, Teamwork Training, and WalkRounds are described, and implementation examples provided. The argument is made that they must be systematically and consistently implemented in an integrated fashion.Conclusions.There are excellent examples of institutions applying Just Culture principles, Teamwork Training, and Leadership WalkRounds—but to date, they have not been comprehensively instituted in health care organizations in a cohesive and interdependent manner. To achieve reliability, organizations need to begin thinking about the relationship between these efforts and linking them conceptually.
Addressing Measurement Error Bias in Nurse Staffing Research
Authors: Harless David W. , Mark Barbara A. 
Published: June 2006

Objective. To assess the extent of measurement error bias due to methods used to allocate nursing staff to the acute care inpatient setting and to recommend estimation methods designed to overcome this bias.Data Sources/Study Setting. Secondary data obtained from the California Office of Statewide Health Planning and Development (OSHPD) and the Centers for Medicare and Medicaid Services' Healthcare Cost Report Information System for 279 general acute care hospitals from 1996 to 2001.Study Design. California OSHPD provides detailed nurse staffing data for acute care inpatients. We estimate the measurement error and the resulting bias from applying different staffing allocation methods. Estimates of the measurement errors also allow insights into the best choices for alternate estimation strategies.Principal Findings. The bias induced by the adjusted patient days method (and its modification) is smaller than for other methods, but the bias is still substantial: in the benchmark simple regression model, the estimated coefficient for staffing level on quality of care is expected to be one‐third smaller than its true value (and the bias is larger in a multiple regression model). Instrumental variable estimation, using one staffing allocation measure as an instrument for another, addresses this bias, but only particular choices of staffing allocation measures and instruments are suitable.Conclusions. Staffing allocation methods induce substantial attenuation bias, but there are easily implemented estimation methods that overcome this bias.
Effect of Dialysis Center Profit‐Status on Patient Survival: A Comparison of Risk‐Adjustment and Instrumental Variable Approaches
Authors: Brooks John M. , Irwin Christopher P. , Hunsicker Lawrence G. , Flanigan Michael J. , Chrischilles Elizabeth A. , Pendergast Jane F. 
Published: June 2006

Objective. To compare the estimated effects of dialysis center profit status on patient survival using alternative estimation strategies with retrospective data.Data Sources/Study Setting. Patient and provider‐level retrospective data from the United States Renal Data System (USRDS), 1996–1999.Study Design. Observational risk adjustment and instrumental variable methods.Data Collection/Extraction Methods. Study collected measures from various USRDS files describing clinical characteristics, survival, and the profit status of the initial dialysis center for incident end‐stage renal disease (ESRD) patients aged 67+. USRDS facility files were used to assess dialysis center profit status and measure patient distances to dialysis centers.Principal Findings. Found survival effect related to profit status in the range of previous research using risk‐adjusting covariates similar to those used in previous models. Adding further risk‐adjusting covariates halved this effect. The relative proximity of for‐profit and nonprofit dialysis centers to the patient residence was the strongest determinant of the profit status of the patient's initial dialysis center. The effect of profit status on survival was eliminated using the two‐stage least squares variant of instrumental variable estimation with the relative proximity of for‐profit and nonprofit dialysis centers to the patient's residence as the instrument.Conclusions. Using only the variation in initial dialysis center profit status that was related to the relative proximity of for‐profit and nonprofit dialysis centers to the patient, we found no relationship between dialysis center profit status and patient survival. These results are in contrast to results obtained using risk‐adjustment methods with a limited set of risk‐adjusting covariates.
Implementing the Institute of Medicine Definition of Disparities: An Application to Mental Health Care
Authors: McGuire Thomas G. , Alegria Margarita , Cook Benjamin L. , Wells Kenneth B. , Zaslavsky Alan M. 
Published: June 2006

Objective. In a recent report, the Institute of Medicine (IOM) defines a health service disparity between population groups to be the difference in treatment or access not justified by the differences in health status or preferences of the groups. This paper proposes an implementation of this definition, and applies it to disparities in outpatient mental health care.Data Sources. Health Care for Communities (HCC) reinterviewed 9,585 respondents from the Community Tracking Study in 1997–1998, oversampling individuals with psychological distress, alcohol abuse, drug abuse, or mental health treatment. The HCC is designed to make national estimates of service use.Study Design. Expenditures are modeled using generalized linear models with a log link for quantity and a probit model for any utilization. We adjust for group differences in health status by transforming the entire distribution of health status for minority populations to approximate the white distribution. We compare disparities according to the IOM definition to other methods commonly used to assess health services disparities.Principal Findings. Our method finds significant service disparities between whites and both blacks and Latinos. Estimated disparities from this method exceed those for competing approaches, because of the inclusion of effects of mediating factors (such as income) in the IOM approach.Conclusions. A rigorous definition of disparities is needed to monitor progress against disparities and to compare their magnitude across studies. With such a definition, disparities can be estimated by adjusting for group differences in models for expenditures and access to mental health services.
Clinical Factors Associated with Quality of Life in Patients with Transient Loss of Consciousness
Authors: VAN DIJK NYNKE , SPRANGERS MIRJAM A. , COLMAN NANCY , BOER KIMBERLY R. , WIELING WOUTER , LINZER MARK 
Published: June 2006

Introduction: Transient loss of consciousness (TLOC) is common and can be lethal. Although the patients with the most prevalent causes of TLOC have a benign prognosis, morbidity is considerable. Aim of this article, therefore, was to compare the generic quality of life (QoL) of patients presenting with TLOC with that of the general population, to compare the disease‐specific QoL with that of an American referral sample, and to examine which sociodemographic and clinical factors are associated with QoL in these patients. Methods: This study was part of the fainting assessment study (FAST), which assessed diagnostic strategies for adult patients presenting with TLOC to the Academic Medical Center Amsterdam, between February 2000 and May 2002. The generic short form‐36 (SF‐36) health survey and the disease‐specific syncope functional status questionnaire (SFSQ) were used to assess QoL. Results: Of 468 included patients, 82% completed the questionnaires. Patients with TLOC scored poorer on all scales of the SF‐36 than the Dutch population, with effect sizes ranging from 0.43 to 1.11 (>0.5 = moderate effect; >0.8 = large effect). The SFSQ indicated mean impairment in 33% of the listed activities (such as driving). Female gender, higher level of comorbidity, shorter duration of complaints, having had more than one syncopal episode, and the presence of presyncopal episodes were associated with poorer QoL. Conclusion: TLOC seriously affects QoL, especially in patients with a recent onset of clinical symptoms and those suffering from both syncopal and presyncopal episodes.
New pulsating white dwarfs in cataclysmic variables
Authors: Nilsson R. , Uthas H. , Ytre-Eide M. , Solheim J-E. , Warner B. 
Published: June 2006

Abstract
The number of discovered non-radially pulsating white dwarfs (WDs) in cataclysmic variables (CVs) is increasing rapidly by the aid of the Sloan Digital Sky Survey (SDSS). We performed photometric observations of two additional objects, SDSS J133941.11+484727.5 (SDSS 1339), independently discovered as a pulsator by Gänsicke et al., and SDSS J151413.72+454911.9, which we identified as a CV/ZZ Ceti hybrid. In this Letter we present the results of the remote observations of these targets performed with the Nordic Optical Telescope (NOT) during the Nordic-Baltic Research School at Moletai Observatory, and follow-up observations executed by NOT in service mode. We also present three candidates we found to be non-pulsating.
The results of our observations show that the main pulsation frequencies agree with those found in previous CV/ZZ Ceti hybrids, but specifically for SDSS 1339 the principal period differs slightly between individual observations and also from the recent independent observation by Gänsicke et al. Analysis of SDSS colour data for the small sample of pulsating and non-pulsating CV/ZZ Ceti hybrids found so far seems to indicate that the r-i colour could be a good marker for the instability strip of this class of pulsating WDs.
Viability of Dynamic Cooling Control in a Data Center
Environment
Authors: Boucher Timothy D. , Auslander David M. , Bash Cullen E. , Federspiel Clifford C. , Patel Chandrakant D. 
Published: June 2006

Abstract
Data center thermal management challenges have been steadily increasing over the past few years due to rack level power density increases resulting from system level compaction. These challenges have been compounded by antiquated environmental control strategies designed for low power density installations and for the worst-case heat dissipation rates in the computer systems. Current data center environmental control strategies are not energy efficient when applied to the highly dynamic, high power density data centers of the future. Current techniques control the computer room air conditioning units (CRACs) based on the return air temperature of the air—typically set near 20°C. Blowers within the CRACs are normally operated at maximum flow rate throughout the operation of the data center unless they are equipped with nonstandard variable frequency drives. At this setting the blowers typically provide significantly more airflow than is required by the equipment racks to prevent recirculation and the subsequent formation of hot spots. This strategy tends to be overly conservative and inefficient. As an example air entering a given system housed in a rack undergoes a temperature rise of 15°C due to the heat added by the system. The return air control strategy strives to keep the entire room at a fixed temperature. Therefore in a typical data center the CRAC supply temperature, and hence the air entering the racks, is 13-15°C and the CRAC return is 20-22°C. At these settings the CRACs can consume almost as much energy as the computer equipment they are cooling [Friedrich, R., Patel, C.D., 2002, “Towards Planetary Scale Computing – Technical Challenges for Next Generation Internet Computing,” THERMES 2002, Santa Fe, NM; The Uptime Institute, “Heat Density Trends in Data Processing, Computer Systems and Telecommunications Equipment,” White Paper issued by The Uptime Institute, 2000.]. Experiments conducted by the authors using these CRAC settings show that nearly 0.7W is consumed by the environmental control system for every 1W of heat dissipated by the computer equipment in the authors’ experimental facility indicating that the energy efficiency of standard data center environmental control systems is poor. This study examines several opportunities for improving thermal management and energy performance of data centers with automatic control. Experimental results are presented that demonstrate how simple, modular control strategies can be implemented. Furthermore, experimental data is presented that show it is possible to improve the energy performance of a data center by up to 70% over current standards while maintaining proper thermal management conditions.
Null-Field Integral
Equation Approach for Plate Problems With Circular
Boundaries
Authors: Chen Jeng-Tzong , Hsiao Chia-Chun , Leu Shyue-Yuh 
Published: June 2006

Abstract
In this paper, a semi-analytical approach for circular plate problems with multiple circular holes is presented. Null-field integral equation is employed to solve the plate problems while the kernel functions in the null-field integral equation are expanded to degenerate kernels based on the separation of field and source points in the fundamental solution. The unknown boundary densities of the circular plates are expressed in terms of Fourier series. It is noted that all the improper integrals are transformed to series sum and are easily calculated when the degenerate kernels and Fourier series are used. By matching the boundary conditions at the collocation points, a linear algebraic system is obtained. After determining the unknown Fourier coefficients, the displacement, slope, normal moment, and effective shear force of the plate can be obtained by using the boundary integral equations. Finally, two numerical examples are proposed to demonstrate the validity of the present method and the results are compared with the available exact solution, the finite element solution using ABAQUS software and the data of Bird and Steele.
Effects of synchronization with host plant phenology occur early in the larval development of a spring folivore
Authors: Jones B.C. , Despland E. 
Published: June 2006

Early spring feeding Lepidoptera depend on synchronization of larval emergence with host plant phenology for optimal growth and development. Physical and chemical characteristics of foliage change over the course of the growing season, and a delay in larval emergence therefore results in larvae foraging on lower quality food. We examine the effect of synchronization of larval emergence with leaf phenology on the entire larval stage of the forest tent caterpillar, Malacosoma disstria Hübner, 1820 (Lepidoptera: Lasiocampidae). Caterpillars were reared from egg hatch to pupation on trembling aspen, Populus tremuloides Michx; 10 days separated egg hatch in the early and late treatments. Late-hatching caterpillars experienced reduced growth in the early instars, but growth in the later instars did not differ between treatments. Reduced growth early in development resulted in both prolongation of the larval stage through the occurrence of additional instars, and lower pupal mass. Aspen foliage quality changes rapidly during leaf expansion, and the late-hatching caterpillars likely missed the narrow window of opportunity for young larvae to feed on high-quality developing foliage. This study demonstrates the importance of early-instar ecology in Lepidoptera.
Do captive male meadow voles experience acute stress in response to weasel odour?
Authors: Fletcher Q.E. , Boonstra R. 
Published: June 2006

The hormonal stress response is adapted to deal with acute (short-term) stressors; however, chronic (long-term) stressors have negative effects on survival and fitness. Field and laboratory evidence suggest that voles respond behaviourally to predator odours. However, it is unknown whether voles mount an acute hormonal stress response to predator odour. We determined whether reproductively active, captive male meadow voles ( Microtus pennsylvanicus (Ord, 1815)) mounted a more pronounced hormonal stress response to weasel odour (ermine, Mustela erminea L., 1758), one of their principal mammalian predators, than to nonpredator and control odours. We compared the corticosterone response of captive voles to weasel, jumping mouse ( Zapus hudsonius (Zimmermann, 1780)), and control odours following acute (20 min) exposure. The hormonal stress response to the treatment odours did not differ, indicating that captive male voles in the reproductive season do not mount an acute stress response to predator odour. We hypothesize that voles do not respond to weasel odour because, independent of other stimuli, olfactory signals are not reliable enough to outweigh the costs, such as suppression of reproduction and reproductive behaviour, associated with a response.
Hatching plasticity in two temperate anurans: responses to a pathogen and predation cues
Authors: Touchon J.C. , Gomez-Mestre I. , Warkentin K.M. 
Published: June 2006

Water molds are widespread in aquatic environments and are important causes of mortality in amphibian and fish eggs. We tested the ability of two species of North American anurans with different breeding phenologies ( Rana sylvatica LeConte, 1825 and Bufo americanus Holbrook, 1836) to alter their hatching timing in response to three indicators of environmental risk: infection with a water mold, exposure to simulated egg predation cues, or exposure to simulated larval predation cues. When infected with water mold (Saprolegniaceae), B. americanus eggs hatched, on average, 44% earlier than the controls and R. sylvatica eggs hatched 19% earlier than the controls. In addition, B. americanus but not R. sylvatica eggs hatched significantly earlier than the controls when exposed to simulated egg and larval predation cues. Bufo americanus embryos hatched before developing muscular response, suggesting that hatching occurs through enzymatic egg capsule degradation combined with ciliary movement, not through behavior. Bufo americanus breeds later than R. sylvatica and responded to infection and simulated predation cues more strongly. This may reflect a history of stronger selection by pathogens and predators that accumulate in ponds as the breeding season progresses. To our knowledge, these are the first examples of induced hatching of amphibians in response to aquatic pathogens.
The Role of Platelet-Derived Growth Factor Receptor in Eotaxin Signaling of Eosinophils
Authors: Adachi Tetsuya , Hanaka Satoko , Yano Tomoko , Yamamura Koichi , Yoshihara Hisanao , Nagase Hiroyuki , Chihara Junichi , Ohta Ken 
Published: June 2006

<i>Background:</i> Receptor tyrosine kinases (RTKs) such as epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor (PDGFR) are capable of eliciting kinase activity after ligand binding. In several cells, RTKs are activated via the G-protein-coupled receptor independent of the ligand-RTK interaction. We have previously found that EGFR is transactivated via CC chemokine receptor 3 in bronchial epithelial cells and that this pathway is important for mitogen-activated protein (MAP) kinase activation and cytokine production. It has recently been suggested that hypereosinophilic syndrome results from the fusion tyrosine kinase FIP1L1-PDGFRA. Although it is possible that the PDGFR signal is involved in eosinophil function, the details are still unclear. <i>Methods:</i> Blood eosinophils were purified using Percoll and anti-CD16 antibody-coated magnetic beads. Expression of PDGFR mRNA was examined by RT-PCR. After stimulating eosinophils with eotaxin, the phosphorylation of MAP kinases was examined by Western blotting with the antiphosphospecific MAP kinase antibody. The eotaxin-induced eosinophil chemotaxis was studied using Boyden chambers. <i>Results:</i> Eosinophils expressed PDGFRβ mRNA in 4 out of 8 donors, while PDGFRα mRNA was expressed in only 1 donor. Protein expression of PDGFR was also detectable in eosinophils from some donors. AG1295, a specific inhibitor of PDGFR, showed dose-dependent inhibition of eotaxin-induced MAP kinase phosphorylation in the eosinophils expressing PDGFRβ mRNA. The chemotaxis of these eosinophils was significantly inhibited by AG1295 (n = 3). <i>Conclusions:</i> Our results suggest that PDGFR modifies the CCR3-MAP kinase signaling pathway and chemotactic response in some donors. The pharmacological targeting of PDGFR may be a new strategy to treat eosinophilic disorders.