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1.
J Geophys Res Space Phys ; 125(2)2020 Feb.
Article in English | MEDLINE | ID: mdl-33505828

ABSTRACT

With no global magnetic field or atmosphere, the Moon was traditionally seen as a perfect absorber of the incoming solar wind. Recently, it has become apparent that magnetic fields with sources in the lunar crust act to reflect a significant percentage of incoming solar wind particles, which can then interact with the surrounding plasma environment and drive plasma waves. Using data collected by the Acceleration, Reconnection, Turbulence, and Electrodynamics of Moon's Interaction with the Sun (ARTEMIS) spacecraft, we look for simultaneous observations of reflected ions and 0.01 Hz waves to study the characteristics and conditions under which wave-particle resonant interactions occur. Analyzing the solar wind and interplanetary magnetic field during these observations reveals particular solar wind and interplanetary magnetic field conditions that favor the generation of these waves. We use an ion tracing program to produce reflected ion distributions for various ambient conditions. These distributions show that the conditions that lead to more ions crossing the equatorial region where ARTEMIS orbits are also those favored for wave observations. Low-frequency waves, such as those generated by cyclotron resonance with ions, can be heavily Doppler shifted, making it difficult to determine their intrinsic properties. Reflected ion distributions for the same ambient conditions as the observed waves suggest that most of the waves are intrinsically right-hand polarized.

2.
J Geophys Res Space Phys ; 122(10): 9983-9993, 2017 Oct.
Article in English | MEDLINE | ID: mdl-33505827

ABSTRACT

Recent studies show that localized crustal magnetic fields on the lunar surface can reflect a significant portion of the incoming solar wind protons. These reflected ions can drive a wide range of plasma waves. It is difficult to determine the intrinsic properties of low-frequency waves with single-spacecraft observations, which can be heavily Doppler shifted. We describe a technique to combine trajectory analysis of reflected protons with the Doppler shift and resonance conditions to identify ultralow-frequency waves at the Moon. On 31 January 2014 plasma waves were detected by one of the Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) probes as it approached the lunar wake; these waves were not detected by the second ARTEMIS probe located upstream in the undisturbed solar wind. The observed waves had a frequency below the local ion cyclotron frequency and had right-hand circular polarization in the reference frame of the Moon. By solving the Doppler shift and the cyclotron resonance equations, we determined the conditions for reflected ions to excite the observed waves. Simulated trajectories of reflected ions correspond to ARTEMIS ion observations and support the hypothesis that reflected ions are the primary driver of the waves. By combining trajectory analysis with the resonance conditions, we identify scenarios where ions that satisfy the resonance conditions are present in the right location to generate the observed waves. Using this method, we can uniquely identify the observed waves as upstream propagating right-hand polarized waves, subject to the assumption that they are generated by cyclotron resonance with ions.

3.
Qual Saf Health Care ; 12(2): 112-8, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12679507

ABSTRACT

OBJECTIVE: To understand fundamental attitudes towards patient safety culture and ways in which attitudes vary by hospital, job class, and clinical status. DESIGN: Using a closed ended survey, respondents were questioned on 16 topics important to a culture of safety in health care or other industries plus demographic information. The survey was conducted by US mail (with an option to respond by Internet) over a 6 month period from April 2001 in three mailings. SETTING: 15 hospitals participating in the California Patient Safety Consortium. SUBJECTS: A sample of 6312 employees generally comprising all the hospital's attending physicians, all the senior executives (defined as department head or above), and a 10% random sample of all other hospital personnel. The response rate was 47.4% overall, 62% excluding physicians. Where appropriate, responses were weighted to allow an accurate comparison between participating hospitals and job types and to correct for non-response. MAIN OUTCOME MEASURES: Frequency of responses suggesting an absence of safety culture ("problematic responses" to survey questions) and the frequency of "neutral" responses which might also imply a lack of safety culture. Responses to each question overall were recorded according to hospital, job class, and clinician status. RESULTS: The mean overall problematic response was 18% and a further 18% of respondents gave neutral responses. Problematic responses varied widely between participating institutions. Clinicians, especially nurses, gave more problematic responses than non-clinicians, and front line workers gave more than senior managers. CONCLUSION: Safety culture may not be as strong as is desirable of a high reliability organization. The culture differed significantly, not only between hospitals, but also by clinical status and job class within individual institutions. The results provide the most complete available information on the attitudes and experiences of workers about safety culture in hospitals and ways in which perceptions of safety culture differ among hospitals and between types of personnel. Further research is needed to confirm these results and to determine how senior managers can successfully transmit their commitment to safety to the clinical workplace.


Subject(s)
Attitude of Health Personnel , Hospital Administration/standards , Organizational Culture , Personnel, Hospital/psychology , Safety Management/organization & administration , Adult , California , Female , Health Care Surveys , Hospital Administrators/psychology , Humans , Male , Medical Staff, Hospital/psychology , Middle Aged , Nursing Staff, Hospital/psychology , Personnel, Hospital/classification , Surveys and Questionnaires
4.
Pediatrics ; 106(4): E45, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11015540

ABSTRACT

OBJECTIVES: Acquisition and maintenance of the skills necessary for successful resuscitation of the neonate are typically accomplished by a combination of completion of standardized training courses using textbooks, videotape, and manikins together with active participation in the resuscitation of human neonates in the real delivery room. We developed a simulation-based training program in neonatal resuscitation (NeoSim) to bridge the gap between textbook and real life and to assess trainee satisfaction with the elements of this program. METHODS: Thirty-eight subjects (physicians and nurses) participated in 1 of 9 full-day NeoSim programs combining didactic instruction with active, hands-on participation in intensive scenarios involving life-like neonatal and maternal manikins and real medical equipment. Subjects were asked to complete an extensive evaluation of all elements of the program on its conclusion. RESULTS: The subjects expressed high levels of satisfaction with nearly all aspects of this novel program. Responses to open-ended questions were especially enthusiastic in describing the realistic nature of simulation-based training. The major limitation of the program was the lack of fidelity of the neonatal manikin to a human neonate. CONCLUSION: Realistic simulation-based training in neonatal resuscitation is possible using current technology, is well received by trainees, and offers benefits not inherent in traditional paradigms of medical education.


Subject(s)
Education, Medical, Continuing/methods , Pediatrics/education , Resuscitation/methods , Delivery Rooms , Educational Technology , Humans , Infant, Newborn , Manikins , Patient Simulation
6.
Anesthesiology ; 89(1): 8-18, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9667288

ABSTRACT

BACKGROUND: Techniques are needed to assess anesthesiologists' performance when responding to critical events. Patient simulators allow presentation of similar crisis situations to different clinicians. This study evaluated ratings of performance, and the interrater variability of the ratings, made by multiple independent observers viewing videotapes of simulated crises. METHODS: Raters scored the videotapes of 14 different teams that were managing two scenarios: malignant hyperthermia (MH) and cardiac arrest. Technical performance and crisis management behaviors were rated. Technical ratings could range from 0.0 to 1.0 based on scenario-specific checklists of appropriate actions. Ratings of 12 crisis management behaviors were made using a five-point ordinal scale. Several statistical assessments of interrater variability were applied. RESULTS: Technical ratings were high for most teams in both scenarios (0.78 +/- 0.08 for MH, 0.83 +/- 0.06 for cardiac arrest). Ratings of crisis management behavior varied, with some teams rated as minimally acceptable or poor (28% for MH, 14% for cardiac arrest). The agreement between raters was fair to excellent, depending on the item rated and the statistical test used. CONCLUSIONS: Both technical and behavioral performance can be assessed from videotapes of simulations. The behavioral rating system can be improved; one particular difficulty was aggregating a single rating for a behavior that fluctuated over time. These performance assessment tools might be useful for educational research or for tracking a resident's progress. The rating system needs more refinement before it can be used to assess clinical competence for residency graduation or board certification.


Subject(s)
Anesthesiology/education , Clinical Competence/standards , Education, Medical/methods , Risk Management , Computer Simulation , Humans
7.
Curr Opin Anaesthesiol ; 11(6): 651-7, 1998 Dec.
Article in English | MEDLINE | ID: mdl-17013286

ABSTRACT

As a group, anesthetists have been the leaders in medicine in the study of vigilance, performance, and safety. This review updates the work that has been done in the last year regarding the study of anesthetist vigilance and performance. Much of this work has been performed with the use of patient simulators.

9.
Hum Factors ; 37(1): 20-31, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7790008

ABSTRACT

Situation awareness has primarily been confined to the aviation field. We believe that situation awareness is an equally important characteristic in the complex, dynamic, and risky field of anesthesiology. We describe three aspects of situations of which the decision maker must remain aware: subtle cues, evolving situations, and special knowledge elements. We provide examples of real or simulated anesthesia situations in which situation awareness is clearly involved in the provision of optimal patient care, and we map the elements of situation awareness onto a cognitive process model of the anesthesiologist. Finally, we consider how situation awareness can be further investigated and taught in this medical domain using anesthesia simulators and analyses of real cases. The study of situation awareness in anesthesiology may provide a good example of the wider application of the concept of situation awareness to nonaerospace environments.


Subject(s)
Anesthesiology , Awareness , Adult , Anesthesiology/education , Cues , Female , Humans , Intraoperative Complications/diagnosis , Intraoperative Complications/therapy , Male , Middle Aged , Task Performance and Analysis
10.
Anesthesiology ; 81(2): 488-500, 1994 Aug.
Article in English | MEDLINE | ID: mdl-8053599

ABSTRACT

BACKGROUND: Pressure to put efficiency, output, or continued production ahead of safety has caused catastrophic accidents in various industries. The authors assessed the attitudes and experiences of anesthesiologists concerning production pressure. METHODS: A random, repeated-mailing survey was conducted among 647 members of the American Society of Anesthesiologists residing in California. Questions were asked about attitudes toward production pressure and other patient safety issues, frequency of occurrence of various operating room events, encounters with situations involving unsafe actions, and ratings of sources of production pressure. RESULTS: Forty-seven percent of those sampled returned surveys. The demographics of the respondent population were largely similar to those of the population of anesthesiologists in California. There was no systematic difference between the respondents to the first versus the second mailing, reducing (but not eliminating) the possibility of self-selection bias. Nearly half (49%) of respondents had witnessed production pressure result in what they believed to be unsafe actions by an anesthesiologist. Such events included elective surgery in patients without adequate evaluation or with significant contraindications to surgery. Anesthesiologists felt pressures within themselves to work agreeably with surgeons, avoid delaying cases, and avoid litigation. They also reported overt pressure by surgeons to proceed with cases instead of cancelling them, and to hasten anesthetic procedures. Some aspects of production pressure were perceived differently by those reimbursed by fee-for-service versus those paid by salary. CONCLUSIONS: Production pressure from internal and external sources is a reality for many anesthesiologists and is perceived in some cases to have resulted in unsafe actions being performed.


Subject(s)
Anesthesiology/statistics & numerical data , Attitude of Health Personnel , Workload/statistics & numerical data , Anesthesiology/economics , California , Fatigue , Female , Humans , Income , Male , Middle Aged , Stress, Physiological/complications , Surveys and Questionnaires
11.
Aviat Space Environ Med ; 63(9): 763-70, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1524531

ABSTRACT

The authors have developed a course in Anesthesia Crisis Resource Management (ACRM) analogous to courses in Crew (Cock-pit) Resource Management (CRM) conducted in commercial and military aviation. Anesthesiologists do not typically receive formal training in crisis management although they are called upon to manage life-threatening crises at a moment's notice. Two model demonstration courses in ACRM were conducted using a realistic anesthesia simulation system to test the feasibility and acceptance of this kind of training. Anesthesiologists received didactic instruction in dynamic decision-making, human performance issues in anesthesia, and in the principles of anesthesia crisis resource management. After familiarization with the host institution's operating rooms and with the simulation environment, they underwent a 2-h simulation session followed by a debriefing session which used a videotape of their simulator performance. Participants rated the course as intense, helpful to their practice of anesthesiology, and highly enjoyable. Several aspects of the course were highly rated, including: videotapes of actual anesthetic mishaps, simulation sessions, and debriefing sessions. Scores on written tests of knowledge about anesthesia crisis management showed a significant improvement following the first course (residents) but not the second course (experienced anesthesiologists). Although the ultimate utility of this training for anesthesiologists cannot easily be determined, the course appeared to be a useful method for addressing important issues of anesthesiologist performance which have previously been dealt with haphazardly. The authors believe that ACRM training should become a regular part of the initial and continuing education of anesthesiologists.


Subject(s)
Anesthesiology/education , Education, Medical, Continuing , Emergency Medicine/education , Critical Care , Patient Simulation
13.
Phys Ther ; 48(9): 981-9, 1968 Sep.
Article in English | MEDLINE | ID: mdl-5679247
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